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  • Biosynthesis of polyhydroxyalkanoates from sucrose by metabolically engineered Escherichia coli strains
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-27
    Yu Jung Sohn; Hee Taek Kim; Kei-Anne Baritugo; Hye Min Song; Mi Hee Ryu; Kyoung Hee Kang; Seo Young Jo; Hoyong Kim; You Jin Kim; Jong-il Choi; Su Kyeong Park; Jeong Chan Joo; Si Jae Park

    Sucrose utilization has been established in Escherichia coli strains by expression of Mannheimia succiniciproducens β-fructofuranosidase (SacC), which hydrolyzes sucrose into glucose and fructose. Recombinant E. coli strains that can utilize sucrose were examined for their abilities to produce poly(3-hydroxybutyrate) [P(3HB)] and poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)] from sucrose. When recombinant E. coli strains expressing Ralstonia eutropha PhaCAB and SacC were cultured in MR medium containing 20 g/L of sucrose, all recombinant E. coli strains could produce P(3HB) from sucrose. Also, recombinant E. coli strains expressing Pseudomonas sp. MBEL 6-19 PhaC1437, Clostridium propionicum Pct540, R. eutropha PhaAB enzymes along with SacC could produce P(3HB-co-LA) from sucrose. Among the examined E. coli strains, recombinant E. coli XL1-Blue produced the highest contents of P(3HB) (53.60 ± 2.55 wt%) and P(3HB-co-LA) (29.44 ± 0.39 wt%). In the batch fermentations, recombinant E. coli XL1-Blue strains completely consumed 20 g/L of sucrose as the sole carbon source and supported the production of 3.76 g/L of P(3HB) and 1.82 g/L of P(3HB-co-LA) with 38.21 wt% P(3HB) and 20.88 wt% P(3HB-co-LA) contents, respectively. Recombinant E. coli strains developed in this study can be used to establish a cost-efficient biorefinery for the production of polyhydroxyalkanoates (PHAs) from sucrose, which is an abundant and inexpensive carbon source.

    更新日期:2020-01-27
  • Laccase immobilized polyaniline/magnetic graphene composite electrode for detecting hydroquinone
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-27
    Congqiang Lou; Tao Jing; Juying Zhou; Jingzhi Tian; Yongjie Zheng; Chao Wang; Zhiyuan Zhao; Jing Lin; Hu Liu; Chunqi Zhao; Zhanhu Guo
    更新日期:2020-01-27
  • A propolis enriched polyurethane-hyaluronic acid nanofibrous wound dressing with remarkable antibacterial and wound healing activities
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-27
    Asghar Eskandarinia; Amirhosein Kefayat; Mosayeb Gharakhloo; Maria Agheb; Darioush Khodabakhshi; Mehdi Khorshidi; Vafa Sheikhmoradi; Mohammad Rafienia; Hossein Salehi

    A biocompatible and antibacterial scaffold with efficient wound healing activity can be an appropriate option for wound dressing application. In this study, polyurethane-hyaluronic acid (PU-HA) nanofibrous wound dressing was fabricated and then enriched with three different concentrations of ethanolic extract of propolis (EEP). The obtained samples were characterized by attenuated total reflectance/Fourier transform infrared spectroscopy, thermal gravimetric analysis, scanning electron microscopy, mechanical investigations, antibacterial tests, water uptake exam, and in vitro and in vivo evaluations. The PU-HA/1% EEP and PU-HA/2% EEP samples exhibited higher antibacterial activity against Staphylococcus aureus (2.36 ± 0.33 and 5.63 ± 0.87 mm), Escherichia coli (1.94 ± 0.12 and 3.18 ± 0.63 mm) in comparison with other samples. However, the PU-HA/1% EEP sample exhibited significantly higher biocompatibility for L929 fibroblast cells in comparison with PU-HA/2% EEP. Also, the PU-HA/1% EEP sample could significantly accelerate the wound healing progression and wound closure at the animal model. At the histopathological analyses, improved dermis development and collagen deposition at the healed wound area of the PU-HA/1% EEP sample in comparison with other groups was observed. These results indicate that 1 wt% EEP enriched PU-HA nanofibrous scaffold can be a promising candidate with considerable biocompatibility, wound healing, and antibacterial activities for further biomedical applications.

    更新日期:2020-01-27
  • Genomic signature of accelerated evolution in a saline-alkaline lake-dwelling Schizothoracine fish
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-27
    Chao Tong; Miao Li

    Tibetan Plateau imposes extremely inhospitable environment on most wildlife. Besides the harsh aquatic environment including hypoxia and chronic cold, high salinity and alkalinity is an increasing threat to Tibetan endemic fishes. Previous genome-wide studies identified key genes contributed to highland fish adaptation to hypoxia and long-term cold, while our understanding of saline and alkaline adaptation in Tibetan fish remains limited. In this study, we performed a comparative genomics analysis in a saline lake-dwelling highland fish Gymnocypris przewalskii, aimed to identify candidate genes that contributed to saline and alkaline adaptation. We found elevated genome-wide rate of molecular evolution in G. przewalskii relative to lowland teleost fish species. In addition, we found nine genes encoding biological macromolecules associated with ion transport functions underwent accelerated evolution in G. przewalskii, which broadly expressed across kidney, gill, liver, spleen, brain and muscle tissues. Moreover, we found putative evidence of ion transport under selection was interacted by co-expression in G. przewalskii adaptation to high salinity and alkalinity environment of Lake Qinghai. Taken together, our comparative genomics study identified a set of rapidly evolving ion transport genes and transcriptomic signatures in Schizothoracine fish adaptation to saline and alkaline environment on the Tibetan Plateau.

    更新日期:2020-01-27
  • Docking interactions determine early cleavage events in insulin proteolysis by pepsin: Experiment and simulation
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-27
    Michał Koliński; Sebastian Kmiecik; Robert Dec; Marcin Piejko; Paweł Mak; Wojciech Dzwolak

    In silico modelling of cascade enzymatic proteolysis is an exceedingly complex and challenging task. Here, we study partial proteolysis of insulin by pepsin: a process leading to the release of a highly amyloidogenic two chain ‘H-fragment’. The H-fragment retains several cleavage sites for pepsin. However, under favorable conditions H-monomers rapidly self-assemble into proteolysis-resistant amyloid fibrils whose composition provides snapshots of early and intermediate stages of the proteolysis. In this work, we report a remarkable agreement of experimentally determined and simulation-predicted cleavage sites on different stages of the proteolysis. Prediction of cleavage sites was based on the comprehensive analysis of the docking interactions from direct simulation of coupled folding and binding of insulin (or its cleaved derivatives) to pepsin. The most frequent interactions were found to be between the pepsin's active site, or its direct vicinity, and the experimentally determined insulin cleavage sites, which suggest that the docking interactions govern the proteolytic process.

    更新日期:2020-01-27
  • Evolutionary insights into bot flies (Insecta: Diptera: Oestridae) from comparative analysis of the mitochondrial genomes
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Xin-yu Li; Li-ping Yan; Thomas Pape; Yun-yun Gao; Dong Zhang

    Bot flies (Oestridae) are obligate endoparasites of mammals, and their extraordinary diversification is of great importance in understanding the evolution of parasitism. However, evolutionary analysis of Oestridae has long been impeded by lack of information. Here, the first three mitochondrial genomes of nasal bot flies (Cephalopina titillator, Cephenemyia trompe and Rhinoestrus usbekistanicus) and a comparative mitochondrial genomic analysis between subfamilies of Oestridae are presented. Contrasting to many other parasites, mitochondrial genomes of oestrids are conserved in structure and genes retain the same order and direction as the ancestral insect mitochondrial genome. Nucleotide composition is highly heterogenous, with Gasterophilinae possessing highest GC content and smallest genomic size. Mitochondrial evolutionary rates vary considerably, with Hypodermatinae and Oestrinae exhibiting a faster average rate than Cuterebrinae and Gasterophilinae. In addition, the first phylogenomic analysis covering all four bot fly subfamilies was conducted, supporting monophyly of Oestridae and a sister-group relationship of Hypodermatinae and Oestrinae. The only topological ambiguity is Cuterebrinae being a sister-group of either (Hypodermatinae + Oestridae) or Gasterophilinae. Thus, we suggest that mitochondrial genomes carry a great potential for phylogenetic analysis of Oestridae, and more information of Cuterebrinae is needed to illuminate the early evolutionary radiation and parasite-host coevolution of bot flies.

    更新日期:2020-01-26
  • Characterization of three novel β-galactosidases from Akkermansia muciniphila involved in mucin degradation
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Konrad Kosciow; Uwe Deppenmeier

    The gut microbe Akkermansia (A.) muciniphila becomes increasingly important as its prevalence is inversely correlated with different human metabolic disorders and diseases. This organism is a highly potent degrader of intestinal mucins and the hydrolyzed glycan compounds can then serve as carbon sources for the organism itself or other members of the gut microbiota via cross-feeding. Despite its importance for the hosts' health and microbiota composition, exact mucin degrading mechanisms are still mostly unclear. In this study, we identified and characterized three extracellular β-galactosidases (Amuc_0771, Amuc_0824, and Amuc_1666) from A. muciniphila ATCC BAA-835. The substrate spectrum of all three enzymes was analyzed and the results indicated a preference for different galactosidic linkages for each hydrolase. All preferred target structures are prevalent within mucins of the colonic habitat of A. muciniphila. To check a potential function of the enzymes for the degradation of mucosal glycan structures, porcine stomach mucin was applied as a model substrate. In summary, we could confirm the involvement of all three β-galactosidases from A. muciniphila in the complex mucin degradation machinery of this important gut microbe. These findings could contribute to the understanding of the molecular interactions between A. muciniphila and its host on a molecular level.

    更新日期:2020-01-26
  • Novel heterocyclic chitosan derivatives and their derived nanoparticles: Catalytic and antibacterial properties
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Andreii S. Kritchenkov; Anton R. Egorov; Alexey A. Artemjev; Ilya S. Kritchenkov; Olga V. Volkova; Elena I. Kiprushkina; Ludmila A. Zabodalova; Elena P. Suchkova; Niyaz Z. Yagafarov; Alexander G. Tskhovrebov; Aleh V. Kurliuk; Tatsiana V. Shakola; Victor N. Khrustalev

    The metal-assisted nitrone-nitrile cycloaddition reaction is apply to empower chitosan chemistry. The ultrasonic irradiation has proven to efficiently accelerate the cycloaddition affording new heterocyclic (1,2,4-oxadiazoline) chitosan derivatives and avoiding ultrasonic degradation of the chitosan macromolecules. By varying the nitrone nature, both water- and toluene-soluble chitosan derivatives were successfully synthesized. Relying on the ionic gelation approach nanoparticles of heterocyclic chitosan derivatives were prepared. Water-soluble chitosan derivative demonstrated a high antibacterial activity coupled with low toxicity. The toxicity of the synthesized heterocyclic chitosan derivatives and their based nanoparticles are comparable with those of the starting chitosan, while their antibacterial activity is superior. Toluene-soluble derivatives are shown to be efficient homogeneous catalysts towards monoglyceride synthesis via the epoxide ring opening. They efficiently catalyze selective conversion of fatty acids and glycidol into corresponding monoglycerides allowing one to simplify significantly the procedure for separating the reaction product from the catalyst for its recovery and reusage.

    更新日期:2020-01-26
  • Decoding allosteric communication pathways in protein lysine acetyltransferase
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Ashfaq Ur Rehman; Mueed Ur Rahman; Shaoyong Lu; Hao Liu; Jia-Yi Li; Taaha Arshad; Abdul Wadood; Ho Leung Ng; Hai-Feng Chen

    In bacteria, protein lysine acetylation circuits can control core processes such as carbon metabolism. In E. coli, cyclic adenosine monophosphate (cAMP) controls the transcription level and activity of protein lysine acetyltransferase (PAT). The M. tuberculosis PatA (Mt-PatA) resides in two different conformations; the activated state and autoinhibited state. However, the mechanism of cAMP allosteric regulation of Mt-PatA remains mysterious. Here, we performed extensive all-atom molecular dynamics (MD) simulations (three independent run for each system) and built a residue-residue dynamic correlation network to show how cAMP mediates allosteric activation. cAMP binds at the regulatory site in the regulatory domain, which is 32 Å away from the catalytic site. An extensive conformational restructuring relieves autoinhibition caused by a molecular Lid (residues 161–203) that shelters the substrate-binding surface. In the activated state, the regulatory domain rotates (~40°) around Ser144, which links both domains. Rotation removes the C-terminus from the cAMP site and relieves the autoinhibited state. Also, the molecular Lid refolds and creates an activator binding site. A conserved residue, His173, was mutated into Lys in the Lid, and during an MD trajectory of the activated state, positioned itself near an acetyl donor molecule in the catalytic domain, suggesting a direct mechanism for acetylation. This study describes the allosteric framework for Mt-PatA and prerequisite intermediate states that permit long-distance signal transmission.

    更新日期:2020-01-26
  • Multifunctional cellulose nanocrystal structural colored film with good flexibility and water-resistance
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Yiyan Huang; Gaowen Chen; Qianmin Liang; Zhuanggang Yang; Huifang Shen
    更新日期:2020-01-26
  • Influence of germination time on the morphological, morphometric, structural, and physicochemical characteristics of Esmeralda and Perla barley starch
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    L.J. Gutiérrez-Osnaya; J.P. Hernández-Uribe; J. Castro-Rosas; A.D. Román-Gutiérrez; B.H. Camacho-Díaz; H.M. Palma-Rodríguez; M.L. Rodríguez-Marín; J. Hernández-Ávila; F.A. Guzmán-Ortiz

    The aim of this study was to analyzing the impact of germination time on the morphology, crystallinity, gelatinization and viscosity properties on the starch of Esmeralda and Perla barley variety. The two barley were germinated for 1 to 8 days, at 26 °C and 65% relative humidity. Micrographs showed the presence of pinholes and eroded surfaces. Starch in Esmeralda was hydrolyzed completely at 8 days of germination. Birefringence was reduced from day 4, losing molecular structuring of the crystalline area. Morphometric data: fractal dimension, area, perimeter, circularity, and roundness decreased significantly along germination time in both varieties. The entropy increased significantly, from 0.79 to 10.09 in Esmeralda and from 0.46 to 7.57 in Perla. Relative crystallinity decreased significantly in the Perla from 24.7% to 23.6%. Viscosity peaks were also significantly reduced, pasting temperature was constant in Esmeralda but in Perla was significantly reduced from 95.43 to 95.19 °C with germination, the gelatinization temperature increased significantly in the Esmeralda while in Perla it remained constant. Enthalpy decreased significantly to 75.8% and 37% in Esmeralda and Perla respectively. The study of germination impact on structural and physicochemical properties is important to identify the use of hydrolyzed starches in the food industry or others.

    更新日期:2020-01-26
  • Arabinogalactan derived from Lycium barbarum fruit inhibits cancer cell growth via cell cycle arrest and apoptosis
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Guiping Gong; Qian Liu; Yangni Deng; Tiantian Dang; Wei Dai; Tingting Liu; Yang Liu; Jing Sun; Langhong Wang; Yuxia Liu; Tingting Sun; Shuang Song; Zhongfu Wang; Linjuan Huang

    Previous studies have shown that crude polysaccharides from the Lycium barbarum fruit could inhibit cancer cell growth, but the major effective constituents are yet to be identified. In this study, we compared the effects of L. barbarum fruit polysaccharide fractions on the growth of hepatoma cells (SMMC-7721 and HepG2), cervical cancer cells (HeLa), gastric carcinoma cells (SGC-7901), and human breast cancer cells (MCF-7). LBGP-I-3 showed stronger inhibitory effects on MCF-7 cells (cell viability of 48.96%) than SMMC-7721 (cell viability of 78.91%) and HeLa cells (cell viability of 55.94%), and had no effect on HepG2 and SGC-7901 cells. In addition, LBGP-I-3 had no inhibitory effect on normal liver cells (L02, cell viability of 115.58%). Investigation of the underlying mechanism suggested that LBGP-I-3 inhibited the growth of cancer cells by cell cycle arrest and apoptosis. LBGP-I-3 arrested the cell cycle at the G0/G1 phase, altered mitochondrial function, activated oxidative stress, and regulated the MAPK signaling pathway to induce apoptosis. Thus, LBGP-I-3 may be a potential functional food ingredient for the prevention of cancer without toxicity to normal cells in vitro. These results could help further elucidate the structure–activity relationship of L. barbarum fruit polysaccharides and functional food development.

    更新日期:2020-01-26
  • 更新日期:2020-01-26
  • Cellulose nanocrystals/nanofibrils loaded astaxanthin nanoemulsion for the induction of apoptosis via ROS-dependent mitochondrial dysfunction in cancer cells under photobiomodulation
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Karuppusamy Shanmugapriya; Hyejin Kim; Yong Wook Lee; Hyun Wook Kang

    The present study investigated effects of low-level laser therapy with cellulose nanocrystals/cellulose nanofibrils loaded in nanoemulsion (NE) against skin cancer cells on apoptosis. The nanoemulsion was fabricated and characterized by the standard methods. The toxicity level by cytotoxicity assays, generation of reactive singlet oxygen (ROS) and antioxidant potential, cell proliferation and migration were confirmed by using standard assays. The cellular uptake efficacy was evaluated by differential staining. The protein levels of EGFR, PI3K, AKT, ERK, GAPDH, and β-actin were detected by western blot. The samples showed a spherical shaped structure with the average size confirmed strong and stable hydrogen bonding forces with high degradation temperature and endothermic transition peaks. The fabricated samples showed no toxicity and high cell proliferation by generating more singlet oxygen levels and antioxidants. The intracellular signaling pathways was regulated with high protein expression levels, which was stimulated by specific molecules for cell proliferation, migration, and differentiation in cancer cells. The results proved that combined treatment regulated the intracellular signaling pathways in cancer cells. The current study showed a novel strategy for improving therapeutic efficacy of nanoemulsion by using low-level laser therapy. Further, the current favorable outcomes will be evaluated in in vivo animal models.

    更新日期:2020-01-26
  • The mineralization process of insoluble elastin fibrillar structures: Ionic environment vs degradation
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Federica Boraldi; Pasquale Moscarelli; Francesco Demetrio Lofaro; Carla Sabia; Daniela Quaglino

    Despite its long half-life and physiological role, elastin undergoes irreversible changes (i.e elastolysis and/or calcification) impairing resilience of soft connective tissues. At present, it is still undefined: 1) to which extent elastin fibers have to be fragmented in order to increase their susceptibility to calcify; 2) which is the contribution of ionic environment on elastin mineralization; 3) why, in the same tissue area, mineralized coexist with non-mineralized fibers. The in vitro mineralization process was investigated on insoluble elastin, hydrolyzed or not-hydrolyzed, and incubated in different cell-free ionic environments. Mineral deposition is favored on hydrolyzed fibrillar structures due to exposure of multiple charged sites increasing the adsorption of Ca2+ that can attract phosphate and increase the local ion concentration over the point of supersaturation, representing the minimum requirement for hydroxyapatite nucleation sites. At physiological pH, the degree of elastin mineralization is influenced by hydrolysis and complexity of medium composition, since ionic species, as sodium, potassium, magnesium, in addition to calcium and phosphorus, interfere with the calcification process. These findings broaden the knowledge on the factors controlling hydroxyapatite deposition on insoluble elastin and can also explain why, in vivo, calcified and non-calcified fibers can be observed within the same tissue.

    更新日期:2020-01-26
  • Development of injectable and durable kefiran hydro-alcoholic gels
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Maria Antonietta Sabatino; Francesco Carfì Pavia; Salvatrice Rigogliuso; Daniela Giacomazza; Giulio Ghersi; Vincenzo La Carrubba; Clelia Dispenza
    更新日期:2020-01-26
  • Graphene oxide-terminated hyperbranched amino polymer-carboxymethyl cellulose ternary nanocomposite for efficient removal of heavy metals from aqueous solutions
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Qiaoping Kong; Sergei Preis; Leli Li; Pei Luo; Yun Hu; Chaohai Wei

    A high-efficiency graphene oxide-terminated hyperbranched amino polymer-carboxymethyl cellulose ternary nanocomposite (GO-HBP-NH2-CMC) was fabricated for adsorbing heavy metals from aqueous solutions. The adsorbent was characterized by SEM, FT-IR, Raman, and XPS analyses showing its porous architecture, rough surface, abundant N- and O-containing functional groups providing enhanced binding ability towards Pb2+ and Cu2+. Experimental adsorption data fitted well to the pseudo-second-order kinetics and Langmuir isotherm models, indicating the adsorption of GO-HBP-NH2-CMC towards Pb2+ and Cu2+ being a chemical and monolayer process. The maximum adsorption capacities of GO-HBP-NH2-CMC for Pb2+ and Cu2+ at 25 °C comprised 152.86 and 137.48 mg/g, respectively. The laboratory-scale experimental study into the Pb2+ and Cu2+ adsorption in a fixed-bed column was undertaken. Effects of flow rate, bed depth and influent metals concentration on the adsorption performance were assessed. Experimental data successfully correlated with the Adams-Bohart, Thomas and Yoon-Nelson models with the R2 exceeding 0.79. Density functional theory calculation was adopted to study interactions between functional groups at GO-HBP-NH2-CMC and heavy metals showing OH, NH2 and COOH moieties in GO-HBP-NH2-CMC being more likely to bind Pb2+ rather than Cu2+, while the binding abilities of -CONH- towards Pb2+ and Cu2+ were similar.

    更新日期:2020-01-26
  • Electrospun gelatin matrices with bioactive pDNA polyplexes
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-25
    Porntipa Pankongadisak; Ekeni Tsekoura; Orawan Suwantong; Hasan Uludağ
    更新日期:2020-01-26
  • Purification and biochemical/biophysical characterization of two hexosaminidases from the fresh water mussel, Lamellidens corrianus
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-24
    Ashapogu Venugopal; Saradamoni Mondal; Kavyashree Sakharayapatna Ranganatha; Debparna Datta; Nadimpalli Siva Kumar; Musti J. Swamy

    Two thermostable isoforms of a hexosaminidase were purified to homogeneity from the soluble extract of freshwater mussel Lamellidens corrianus, employing a variety of chromatographic techniques. Hexosaminidase A (HexA) is a heterodimer with subunit masses of ~80 and 55 kDa. Hexosaminidase B (HexB) is a homodimer with a subunit mass of 55–60 kDa. Circular dichroism spectroscopic studies indicated that both HexA and HexB contain β-sheet as the major secondary structural component with considerably lower content of α-helix. The temperature and pH optima of both the isoforms were found to be 60 °C and 4.0, respectively. The IC50 values for HexA with N-acetyl-d-galactosamine, N-acetyl-d-glucosamine, d-galactosamine, d-glucosamine, methyl α-d-mannopyranoside and d-mannose are 3.7, 72.8, 307, 216, 244 and 128 mM, respectively, whereas the corresponding IC50 values for HexB were estimated as 5.1, 61, 68, 190, 92 and 133 mM, respectively. Kinetic parameters KM and Vmax for HexA and B with p-nitrophenyl N-acetyl-β-d-glucosaminide are 4 mM, 0.23 μmol·min−1·mL−1 and 2.86 mM, 0.29 μmol·min−1·mL−1, respectively, and with p-nitrophenyl N-acetyl-β-d-galactosaminide are 4.5 mM, 0.054 μmol·min−1·mL−1 and 1.4 mM, 0.14 μmol·min−1·mL−1, respectively. GalNAc inhibited both isoforms in a non-competitive manner, whereas a mixed mode of inhibition was observed with GlcNAc with both forms.

    更新日期:2020-01-24
  • Structural characterization and neuroprotective effect of a polysaccharide from Corydalis yanhusuo
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-24
    Yufeng He; Wenzhong Xu; Yimin Qin; Jinning Song

    In the present study, we investigated the neuroprotective effects of a purified Corydalis yanhusuo polysaccharide (CYP) on Aβ (25–35)-induced neurotoxicity and explored its underlying molecular mechanisms in PC12 cells. The results showed pretreatment with CYP (25, 50, and 100 μg/ml) prior to Aβ (25–35) exposure significantly protected PC12 cells from Aβ (25–35)-induced cell death, lactate dehydrogenase (LDH) release, DNA fragmentation, mitochondrial dysfunction and mitochondrial cytochrome c release. Moreover, Aβ (25–35)-induced increase of ratio between Bax and Bcl-2 protein expression was dramatically reversed by CYP pretreatment. Furthermore, the addition of CYP led to a significant repressing effect on the elevated protein expression of cleaved caspase-8, caspase-9, and caspase-3 in Aβ (25–35)-treated PC12 cells. Taken together, these findings indicated that protective effect of CYP against Aβ (25–35)-induced toxicity in PC12 cells was probably mediated by inhibition of apoptosis via both mitochondrial apoptotic pathway and death receptor pathway.

    更新日期:2020-01-24
  • Influence of different salts on rheological and functional properties of basil (Ocimum bacilicum L.) seed gum
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-24
    Reza Farahmandfar; Sara Naji-Tabasi

    In this paper, the influence of a variety of salts (NaCl, CaCl2, and KCl) at different concentrations (0, 0.1, 0.5 and 1% w/w) on rheological and functional properties of basil seed gum (BSG) were investigated. BSG produced a high viscosity solution with yield stress, which was a function of salt type and concentration. In all samples, viscosity decreased as the electrostatic interactions between the BSG chains altered by salts. Flow behavior index increased by salt addition, which shows BSG had weaker shear-thinning behavior and worse mouthfeel in the presence of salts. The viscoelasticity of BSG strongly influenced by the addition of salt type as well as concentration. Larger cations (Ca+2) shield the electrostatic interaction between BSG chains more strongly compared to smaller cations as they have larger hydrated radius. As a result divalent salts decreased the viscosity and viscoelasticity more significantly. Emulsion capacity improved by salts addition, especially at high concentrations of salts. The foam capacity increased in the presence of CaCl2 and KCl increased foaming capacity of BSG. The results suggest that the addition of the different types of salt can alter or modify the rheological and functional properties of BSG, depending on the salt concentration.

    更新日期:2020-01-24
  • Salmonella enterica Serovar Typhi exposure elicits deliberate physiological alterations and triggers the involvement of ubiquitin mediated proteolysis pathway in Caenorhabditis elegans
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-24
    Boopathi Balasubramaniam; Lappasi Mohanram VenkataKrishna; Thondimuthu Vinitha; Gnanasekaran JebaMercy; Krishnaswamy Balamurugan
    更新日期:2020-01-24
  • Chitosan mediated solid lipid nanoparticles for enhanced liver delivery of zedoary turmeric oil in vivo
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-24
    Bo Yang; Jiaqi Jiang; Lei Jiang; Peiyu Zheng; Fuling Wang; Yang Zhou; Zhong Chen; Minghui Li; Mingming Lian; Shukun Tang; Xiaoying Liu; Haisheng Peng; Qun Wang

    Zedoary turmeric oil (ZTO) has a strong antitumor activity. However, its volatility, insolubility, low bioavailability, and difficulty of medication owing to oily liquid limit its clinical applications. Solid lipid nanoparticles can provide hydrophobic environment to dissolve hydrophobic drug and solidify the oily active composition to decrease the volatility and facilitate the medication. Chitosan has been widely used in pharmaceutics in recent years and coating with chitosan further enhances the internalization of particles by cells due to charge attract. Here, Chitosan (CS)-coated solid lipid nanoparticles (SLN) loaded with ZTO was prepared and characterized using dynamic laser scanner (DLS) and transmission electron microscope (TEM). The uptake and distribution of drug were evaluated in vitro and in vivo. The average sizes of ZTO-SLN and CS-ZTO-SLN were 134.3 ± 3.42 nm and 210.7 ± 4.59 nm, respectively. CS coating inverted the surface charge of particles from −8.93 ± 1.92 mV to +9.12 ± 2.03 mV. The liver accumulation of CS-ZTO-SLN was higher than ZTO-SLN (chitosan-uncoated particles) by analysis of tissue homogenate using HPLC, and the bioavailability of ZTO was also obviously improved. The results suggested that SLN coated with CS improved the features of ZTO formulation and efficiently deliver drug to the liver.

    更新日期:2020-01-24
  • 更新日期:2020-01-24
  • Improved characterization of nanofibers from bacterial cellulose and its potential application in fresh-cut apples
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-24
    Xichuan Zhai; Dehui Lin; Wenwen Li; Xingbin Yang

    The present research aimed to study the nanofibers from bacterial cellulose (BC) by HCl and explore its new potential application in fresh-cut apples. Bacterial cellulose nanofibers (BCNs) showed low and more homogeneity particle size, as well as higher zeta potential and transparency in comparison with BC, which was confirmed by morphological analysis. Physical properties analysis showed that BCNs was more excellent semi-crystalline polymer with higher thermal stability as compared with BC. Rheological results displayed that BCNs suspensions presented a shear thinning behavior with higher apparent viscosity, storage (G′) and loss (G′′) moduli at the same concentration in comparison with BC. Furthermore, BCNs suspensions were more stable than BC suspensions under storage condition of 4 °C. Additionally, 2% (wt%) of BCNs suspensions were coated on fresh-cut apples. Results showed that the samples coated with BCNs suspension displayed more excellent properties of keeping fresh-cut apples as compared with that coated with BC suspensions, including delaying weight loss, improving firmness and soluble solids content, reducing browning index and titratable acidity. Therefore, the low cost and high biocompatibility of BCNs can be used as new coatings for fresh-cut apples and have great potential to coat fresh-cut fruits and vegetables in food industry.

    更新日期:2020-01-24
  • Enzyme embedded metal organic framework (enzyme–MOF): De novo approaches for immobilization
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-24
    Shamraja S. Nadar; Leena Vaidya; Virendra K. Rathod
    更新日期:2020-01-24
  • Cistanche polysaccharides enhance echinacoside absorption in vivo and affect the gut microbiota
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-24
    Zhifei Fu; Lifeng Han; Zhang Peng; Haoping Mao; Han Zhang; Yuefei Wang; Xiumei Gao; Erwei Liu

    The polysaccharides and phenylethanoid glycosides from Cistanche deserticola have been demonstrated with various health benefits, however the interactive effect between these two kinds of compounds in vivo are not in detail known. The objective of this study was to investigate the synergistic actions of cistanche polysaccharides with phenylethanoid glycoside and the effects of polysaccharides on gut microbiota. Sprague-Dawley rats were fed with different kinds of cistanche polysaccharides for 20 days, on the last day, all rats were administered the echinacoside at 100 mg/kg. The results were compared mainly on the difference of pharmacokinetic parameters, gut microbiota composition, and short chain fatty acids contents. The results indicated that all the cistanche polysaccharides, including crude polysaccharide, high molecular weight polysaccharide and low molecular weight polysaccharide, could regulate the gut microbiota diversity, increase beneficial bacteria and particularly enhance the growth of Prevotella spp. as well as improve the production of short chain fatty acids and the absorption of echinacoside. By exploring the synergistic actions of polysaccharides with small molecules, these findings suggest that cistanche polysaccharides, particularly low molecular weight polysaccharides, could be used as a gut microbiota manipulator for health promotion.

    更新日期:2020-01-24
  • 更新日期:2020-01-24
  • Structural features, selenization modification, antioxidant and anti-tumor effects of polysaccharides from alfalfa roots
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-24
    Pinyi Gao; Jun Bian; Shuangshuang Xu; Changfeng Liu; Yuqiu Sun; Gongling Zhang; Danqi Li; Xuegui Liu

    Hot water extraction and chromatographic purification methods were used to extract and purify two polysaccharides (RAPS-1 and RAPS-2) from the roots of alfalfa. Subsequently, RAPS-2 was modified using the HNO3/Na2SeO3 method to obtain Se-RAPS-2. The structural features, antioxidant and in vitro anti-tumor activities of the three polysaccharides were evaluated. The structural analysis revealed that RAPS-1 (Mw = 10.0 kDa) was composed of rhamnose, xylose, arabinose, galacturonic acid, mannose and glucose, whereas RAPS-2 (Mw = 15.8 kDa) consisted of rhamnose, xylose, galacturonic acid, mannose, glucose and galactose. RAPS-1 contained 1 → 2, 1 → 4, 1 → 3, and 1 → 6 or 1 → glycosidic bonds; however, while RAPS-2 lacked 1 → 4 glycosidic linkages. The molecular weight of Se-RAPS-2 was 11.0 kDa less than that of RAPS-2. The results of activities demonstrated that Se-RAPS-2 displayed superior antioxidant activity and inhibitory effect in HepG2 cells than RAPS-1 and RAPS-2.

    更新日期:2020-01-24
  • Incorporation of dexamethasone-loaded mesoporous silica nanoparticles into mineralized porous biocomposite scaffolds for improving osteogenic activity
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-24
    Xiaojun Zhou; Pengchao Liu; Wei Nie; Chen Peng; Tao Li; Lei Qiang; Chuanglong He; Jinwu Wang

    The development of ideal organic-inorganic composite scaffold with porous structure and favorable osteoinductive properties that mimics the extracellular matrix composition of bone, is essential for the guidance of new bone formation in orthopaedic practice. Nowadays, numerous efforts have been dedicated to constructing implantable biocomposite scaffolds with appropriate structure and bioactivity for repairing bone defects. In this study, we fabricated chitosan-alginate-gelatin (CAG)-based porous biocomposite scaffolds with calcium phosphate coating on the surface and dexamethasone (DEX)-loaded mesoporous silica nanoparticles within the scaffold, which allows sustained release of DEX for bone tissue engineering application. The inorganic components of calcium phosphate crystals formed on the wall of scaffolds were obtained through electrochemical deposition method. The hybrid mineralized scaffolds demonstrate significantly high mechanical strength and reduced swelling property compared with pristine CAG scaffolds. The in vitro proliferation and osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (BMSCs) cultured on biocomposite scaffolds were significantly enhanced. Furthermore, in vivo experiments revealed that biocomposite scaffolds with minerals deposition and DEX loading showed better new bone formation ability, as compared to pure CAG scaffold and single mineralized scaffold. Therefore, the developed biocomposite scaffolds may be highly promising as local implantable scaffolds for potential applications in bone tissue engineering.

    更新日期:2020-01-24
  • Delineating the venom toxin arsenal of Malabar pit viper (Trimeresurus malabaricus) from the Western Ghats of India and evaluating its immunological cross-reactivity and in vitro cytotoxicity
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Muralidharan Vanuopadath; Sanu Korumadathil Shaji; Dileepkumar Raveendran; Bipin Gopalakrishnan Nair; Sudarslal Sadasivan Nair

    The venom protein components of Malabar pit viper (Trimeresurus malabaricus) were identified by combining SDS-PAGE and ion-exchange chromatography pre-fractionation techniques with LC-MS/MS incorporating Novor and PEAKS-assisted de novo sequencing strategies. Total 97 proteins that belong to 16 protein families such as L-amino acid oxidase, metalloprotease, serine protease, phospholipase A2, 5′-nucleotidase, C-type lectins/snaclecs and disintegrin were recognized from the venom of a single exemplar species. Of the 97 proteins, eighteen were identified through de novo approaches. Immunological cross-reactivity assessed through ELISA and western blot indicate that the Indian antivenoms binds less effectively to Malabar pit viper venom components compared to that of Russell's viper venom. The in vitro cell viability assays suggest that compared to the normal cells, MPV venom induces concentration dependent cell death in various cancer cells. Moreover, crude venom resulted in chromatin condensation and apoptotic bodies implying the induction of apoptosis. Taken together, the present study enabled in dissecting the venom proteome of Trimeresurus malabaricus and revealed the immuno-cross-reactivity profiles of commercially available Indian polyvalent antivenoms that, in turn, is expected to provide valuable insights on the need in improving antivenom preparations against its bite.

    更新日期:2020-01-24
  • A β-glucan from Grifola frondosa effectively delivers therapeutic oligonucleotide into cells via dectin-1 receptor and attenuates TNFα gene expression
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Hao Cui; Xinying Zhu; Zhengyi Huo; Bingbing Liao; Jingping Huang; Zhenxing Wang; Chunhui Song; Xiangguo Hu; Jianping Fang

    Grifola frondosa is an edible and medicinal mushroom with great nutritional values and bioactivities. In the present study, a soluble homogeneous β-glucan, GFPS, with high molecular mass of 5.42 × 106 Da was purified from the fruit bodies of Grifola frondosa using 5% cold NaOH. The structure of GFPS was determined with FT-IR, NMR, and monosaccharide composition analysis, and was identified to be a β-D-(1-3)-linked glucan backbone with a single β-D-(1-6)-linked glucopyranosyl residue branched at C-6 on every third residue. Our results indicated that GFPS had a triple helical structure and could form complex with polydeoxyadenylic acid (poly[A]). Further studies demonstrated that GFPS could interact with poly[A] moiety of a designed antisense oligonucleotide (ASO) targeting the primary transcript of proinflammatory cytokine TNFα (TNFα-A60). This GFPS-based complex could incorporate TNFα-A60 into the macrophage cells via dectin-1 receptor and attenuate lipopolysaccharide-induced secretion of TNFα. Our results suggested that GFPS could be applied to deliver therapeutic oligonucleotides for the treatment of diseases such as inflammation and cancers.

    更新日期:2020-01-24
  • Study on the chemical modification of alkali lignin towards for cellulase adsorbent application
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Hongyan Mou; Jin Huang; Weiying Li; Xiao Wu; Yibei Liu; Huiming Fan
    更新日期:2020-01-24
  • Evaluation of the inter-particle interference of cellulose and lignin in lignocellulosic materials
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Chukwuzubelu Okenwa Ufodike; Vincent Obiozo Eze; Mohammad Faisal Ahmed; Abiodun Oluwalowo; Jin Gyu Park; Okenwa I. Okoli; Hui Wang

    The inter-particle interference of lignocellulosic materials describes the order of the macromolecules at a larger size scale, which can give information about the pore structure, and interface of cellulose and lignin. The pore structure and interface influence the rate of enzymatic hydrolysis and thermal decomposition in cellulosic ethanol manufacturing. In this study, the inter-particle interference of cellulose and lignin of three major categories of lignocellulosic materials: wood-based (cedar and oak), energy crop (bamboo), and agricultural or forestry waste (palm) were evaluated. Scanning electron microscopy (SEM) reveals morphological irregularities in the case of bamboo and palm, which may form nucleation sites for faster accessibility to enzyme molecules. Small-angle X-ray scattering (SAXS) shows increased power-law exponent for palm, suggesting a less clustered structure, which was consistent with the rough surface morphology as detected by the SEM. Differential Scanning Calorimetry (DSC) showed a higher temperature maximum for cedar and oak, which is indicative of higher intermolecular forces within their organic compounds, and could result in slower disintegration of the macromolecules during biochemical processing. This study will help to estimate the activity of the macromolecules and absorption capacity of lignocellulosic materials during biochemical processing.

    更新日期:2020-01-23
  • Controlled release of silver ions from AgNPs using a hydrogel based on konjac glucomannan and chitosan for infected wounds
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Yungang Jiang; Jinjian Huang; Xiuwen Wu; Yanhan Ren; Zongan Li; Jianan Ren

    Konjac glucomannan is a biocompatible polysaccharide with high medicinal potential. In this study, we prepared a hydrogel using an optimized crosslinking konjac glucomannan and chitosan. Silver nanoparticles (AgNPs) were incorporated into the hydrogel to enhance its antimicrobial property. This nanocomposite hydrogel could absorb wound exudates due to its swelling ability, and showed self-healing property that enabled structure stability. Moreover, as a carrier, the hydrogel could modulate the release of silver ions burst, thereby reducing AgNPs cytotoxicity. Rats models with infected skin defects were used to assess wound healing. The results indicated that AgNPs hydrogels dressing could promote wound healing and reduce inflammatory response, exhibiting great clinical application potentials.

    更新日期:2020-01-23
  • Soluble beta-glucan salecan improves vaginal infection of Candida albicans in mice
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Xiaqing Sun; Yan Gao; Zhao Ding; Yang Zhao; Yunxia Yang; Qi Sun; Xiao Yang; Wenhao Ge; Xi Xu; Rui Cheng; Jianfa Zhang

    Vulvovaginal candidiasis (VVC) is one of the most common infections in women. The purpose of this study was to evaluate the ability of a water-soluble β-glucan salecan to protect against Candida albicans (C. albicans) vaginal infection. The model was reproduced with intravaginal inoculation of yeast blastoconidia in pseudoestrus mice. We found that mice that received salecan (0.5 mg per mouse) after infection had 85% fewer CFU than infected mice given saline. Compared with the C. albicans group, salecan reduced the migration of polymorphonuclear neutrophils (PMNs) in the vagina, decreased mRNA levels of cytokines IL23, IL22, IL17a, and IL17f, anti-candidal genes S100a8 and S100a9 and C. albicans pattern recognition receptor Dectin1. The analysis for vaginal microbial community composition at different taxa levels revealed that the bacterial flora composition in the vagina of the salecan-treated mice was similar to that of the uninfected mice, and distinguished from the infected mice. The vaginal lavages from the salecan treated group had more Enterococcus and its metabolite lactate. Our results suggest salecan might be a potential therapeutic agent for vaginal infection of C. albicans.

    更新日期:2020-01-23
  • Anticancerous potential of polysaccharides sequentially extracted from Polygonatum cyrtonema Hua in Human cervical cancer Hela cells
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Ling Li; Kiran Thakur; Yu-Yao Cao; Bu-Yan Liao; Jian-Guo Zhang; Zhao-Jun Wei

    The anticancerous effects of PCHPs (HBSS, CHSS, DASS, and CASS) were investigated on Human cervical cancer Hela cells proliferation inhibition, cytotoxicity, caspase-3 activity, cell cycle, and apoptosis. The inhibition rate was expressed as CASS > HBSS > CHSS > DASS, with the maximum inhibition of 74.453 ± 3.399%. Cell cytotoxicity was observed (CASS > CHSS > HBSS > DASS) with the maximum cell death rate of 82.472 ± 3.488%. The caspase-3 activity was induced by CASS > HBSS > DASS > CHSS, with the maximum multiple of 2.954 ± 0.103. CASS induced cell cycle block at the G2/M phase by elevating mRNA expression of CyclinD1, p21, p53 and Wee1, and lowering the expression of Survivin, CHK2, Wee1, CyclinB1, and CDK-1. CASS enhanced the mRNA expression of DR3, DR5, FasL, FADD, PARP, TNF- α, TNF- R1, TRDAA, caspases-8, caspases-10 and the protein expression of FasL and caspases-8, -10 in the death receptor pathway; while, lowered the mRNA expression of antiapoptotic genes (Bcl - 2 and Bcl-xL) and the protein expression of Bcl - 2. The mRNA expression of apoptosis genes (Bak, Cytc, Puma, and caspases-3, -7, -9) and the protein expression of caspases-3, -9 of mitochondria pathway was up regulated which led to cell apoptosis.

    更新日期:2020-01-23
  • Antioxidant, antibacterial and anti-cancer activities of β-and γ-CDs/curcumin loaded in chitosan nanoparticles
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Nina Alizadeh; Shokufeh Malakzadeh

    Curcumin, as a naturally occurring polyphenol, has been extensively used as anticancer and antioxidant agent due to its ability to protect cells from oxidative damage. In the present study, we have prepared highly soluble CUR-β-cyclodextrin (β-CD) and γ-cyclodextrin (γ-CD) hollow spheres. UV–Vis method was employed to approve the successful formation of the inclusion complex where the aromatic ring of CUR has been encapsulated by the hydrophobic cavity of CDs. CUR-CDs were then encapsulated into positively charged biodegradable chitosan (CUR-CDs-CS) nanoparticles. The CUR-CD-CS were characterized by UV–Vis, FTIR, 1HNMR, XRD, SEM analysis. Antibacterial efficacy was evaluated by measuring the zone of inhibition scale and MIC value which was recorded as 32 μg/mL and 64 μg/mL for both Gram positive S. aureus and Gram negative E. coli bacteria respectively. We tested the efficacy of these CUR-CD-CS nanoparticles in A549 cell lines using MTT assay and investigated its cellular uptake mechanism. Our results demonstrated that CUR-CD-CS nanoparticles showed superior in vitro release performance and higher cytotoxicity in A549 cell line among all tested formulations. Antioxidant activity and release behavior of the curcumin-loaded CDs-CS was investigated. The IC50 value for CUR/CD-CS was estimated based on their inhibition percent–concentration curves using DPPH assay.

    更新日期:2020-01-23
  • Physical and antimicrobial properties of neutral nanoemulsions self-assembled from alkaline thyme oil and sodium caseinate mixtures
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Yue Zhang; Qixin Zhong

    The objective of this study was to utilize self-assembly properties of sodium caseinate to prepare nanoemulsions after neutralization of alkaline mixtures with 2% w/v caseinate and up to 3% v/v thyme oil. The encapsulation efficiency was >90% at a surfactant-to-oil ratio of up to 1:1.25. The nanoemulsions had structures smaller than 75 nm according to atomic force microscopy and stable hydrodynamic diameters of ~90–200 nm during 20-day storage at room temperature. When tested against Escherichia coli O157:H7 ATCC 43895 and Staphylococcus aureus ATCC 25923 in tryptic soy broth and milk, the encapsulated thyme oil was more active than free thyme oil. Additionally, S. aureus was more resistant than E. coli O157:H7, requiring 11.7 and 5 g/L of encapsulated thyme oil, respectively, to completely deactivate bacteria in milk in 4 h. The findings suggest that thyme oil nanoemulsions can be potentially used as natural preservatives to improve food safety.

    更新日期:2020-01-23
  • Deciphering the role of premicellar and micellar concentrations of sodium dodecyl benzenesulfonate surfactant in insulin fibrillation at pH 2.0
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Javed Masood Khan; Ajamaluddin Malik; Priyankar Sen; Aqeel Ahmad; Anwar Ahmed; Akhtar Atiya

    Amyloid fibril formation by proteins and their deposition in cells and tissues are associated with several amyloid-based disorders. Understanding the mechanism of amyloid fibril formation is thus of the utmost importance for the designing ligands that could prevent or inhibit the fibrillation process and help to treat of such disorders. We describe the stimulatory effect of sodium dodecyl benzenesulfonate (SDBS) on insulin amyloid fibrillation at pH 2.0 and the characterization of SDBS-induced insulin aggregation using spectroscopy and microscopy. We found that SDBS induced amyloid-like aggregates of insulin at sub-micellar (0.1–1.2 mM), but not post-micellar (≥2.0 mM) concentrations. The amyloid fibrillation of insulin induced by SDBS was kinetically rapid and escaped the lag phase. Far-UV CD findings suggested that the α-helical content of insulin transformed into cross-β structure and mixed α and β structures when incubated with sub-micellar and post-micellar SDBS concentrations, respectively. The overall results indicated that low, but not high SDBS concentrations induce amyloid-like insulin aggregates and fibrils.

    更新日期:2020-01-23
  • 更新日期:2020-01-23
  • Hydrophobically-modified gelatin hydrogel as a carrier for charged hydrophilic drugs and hydrophobic drugs
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Takayuki Takei; Ryosuke Yoshihara; So Danjo; Yoshiki Fukuhara; Courtney Evans; Rio Tomimatsu; Yoshihiro Ozuno; Masahiro Yoshida

    Gelatin molecules have been chemically crosslinked using potentially cytotoxic reagents to prepare stable hydrogels. Hydrophobic interaction is a means of forming physical crosslinks that is a good candidate for enhancing the stability of gelatin hydrogels without using cytotoxic chemicals. In this study, we proposed a new method to fabricate hydrogels from hydrophobically-modified gelatin (HMG) with high content of hydrophobic segments. HMG was first dissolved in dimethyl sulfoxide and poured into a vial with the desired shape. After the solution was freeze-dried, the solid construct was hydrated. The HMG hydrogel containing basic fibroblast growth factor promoted angiogenesis in vivo, indicating that the positively charged hydrophilic growth factor formed an electrostatic complex with negatively charged HMG hydrogel and was gradually released in vivo with the degradation of the hydrogel. In addition, we showed that the hydrophobic segments of HMG enhanced the adsorption of fluorescein sodium, a model for hydrophobic therapeutic agents, to the hydrogel through hydrophobic interaction. Furthermore, in vitro experiments indicated that the hydrophobic agents would be released from the hydrogel in a controlled manner in vivo. These results show that the HMG hydrogel has significant potential as a carrier for both charged hydrophilic drugs and hydrophobic drugs.

    更新日期:2020-01-23
  • Effect of a low melting temperature mixture on the surface properties of lignocellulosic flax bast fibers
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Sophie Morin; Brieuc Lecart; Thibaut Istasse; Claire Bailly Maître Grand; Fatma Meddeb-Mouelhi; Marc Beauregard; Aurore Richel

    Bast flax fibers were treated, with or without ultrasound assistance, using a low melting mixture (LMM) composed of lactic acid, d-glucose and water. This LMM treatment affected both lignin and hemicelluloses contents and modified the fibers properties identified as crucial parameters in an industrial context, i.e. coloration, wettability, crystallinity, fibers diameter and chemical composition. Surface chemistry of the fibers were investigated through fluorescent tagged carbohydrates binding modules revealing macromolecular rearrangements responsible of both a fibers crystallinity enhancement and an unexpected hydrophobicity. It has been found that LMM treatments bleach fibers, which is considered a beneficial effect independent of the treatments.

    更新日期:2020-01-23
  • Characterization of G-quadruplex formation in the ARID1A promoter
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Ting Yan; Bo Zhao; Qiong Wu; Wenmeng Wang; Jinming Shi; Dangdang Li; Daniel B. Stovall; Guangchao Sui

    As a member of the SWI/SNF family, ARID1A plays an essential role in modulating chromatin structure and gene expression. The tumor suppressive function of ARID1A has been well-defined and its downregulation in cancers is attributed to genomic deletion, DNA methylation and microRNA-mediated inhibition. In this study, we demonstrated that the negative strand of a C-rich region in the upstream vicinity of the human ARID1A transcription start site could form G-quadruplexes. Synthesized oligonucleotides based on the sequence of this region exhibited molar ellipticity at specific wavelengths characteristic of G-quadruplex structures in circular dichroism analyses. The formation of G-quadruplexes by these oligonucleotides were also proved by native polyacrylamide gel electrophoresis, DNA synthesis block assays, immunofluorescent staining and dimethyl sulfate footprinting studies. In reporter assays, mutations of the G-quadruplex forming sequence reduced ARID1A promoter-mediated transcription. Transfection of the oligonucleotide with the full length of G-quadruplex motif region, but not its partial sequences or the mutants, could both promote endogenous ARID1A expression and reduce cell proliferation.

    更新日期:2020-01-23
  • Human embryonic stem cell-derived neural stem cells encapsulated in hyaluronic acid promotes regeneration in a contusion spinal cord injured rat
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Masoumeh Zarei-Kheirabadi; Hoda Sadrosadat; Atiyeh Mohammadshirazi; Razieh Jaberi; Farzaneh Sorouri; Fahimeh Khayyatan; Sahar Kiani
    更新日期:2020-01-23
  • Mucin-polysaccharide interactions: A rheological approach to evaluate the effect of pH on the mucoadhesive properties
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Valéria Maria de Oliveira Cardoso; Maria Palmira Daflon Gremião; Beatriz Stringhetti Ferreira Cury

    The design of mucoadhesive drug delivery systems (DDS) based on polysaccharides at nanoscale or microscale is a relevant technological strategy for the mucosal delivery of several drugs. Findings about the potential mucoadhesive ability of these materials, and the mechanisms that drive such interactions represents an important advance for the rational modulation of such properties, according specific therapeutic needs. The potential mucoadhesive abilities of gellan gum (GG) and retrograded starch (RS) were investigated at pH 1.2 and 6.8, which were considered biorrelevant for the gastrointestinal tract (GIT). The effects of these polysaccharides on the MUC rheology were also addressed. Rheological studies revealed high MUC-GG interactions at both pH values (1.2 and 6.8), expressing a high mucoadhesive ability, mainly in acidic media. MUC-GG interactions were driven, mainly, by hydrogen bonds. At an acidic pH, significant changes occurred in the MUC arrangements due to the strong MUC-GG interactions, as corroborated by scanning electron microscopy (SEM). The rheological behavior of MUC-RS indicated poor interactions between them and MUC arrangements were more preserved as evidenced by SEM. The results of this work indicate that the mixing of GG and RS can be a promising strategy to modulate mucoadhesiveness of DDS, according to specific therapeutic needs.

    更新日期:2020-01-23
  • Adsorption capacity and cold-water solubility of honeycomb-like potato starch granule
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Chenlu Fang; Junrong Huang; Qi Yang; Huayin Pu; Shuxing Liu; Zhenbao Zhu
    更新日期:2020-01-23
  • Protein-reduced gold nanoparticles mixed with gentamicin sulfate and loaded into konjac/gelatin sponge heal wounds and kill drug-resistant bacteria
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Yini Zou; Ruiqi Xie; Enling Hu; Ping Qian; Bitao Lu; Guangqian Lan; Fei Lu

    Timely antibacterial treatment of wounds reduces the probability of wound infection and promotes wound healing. However, the materials used to treat wounds often fail to provide both sterilization (especially for super bacteria) and moisture, and some may even cause secondary injury to the wound. In this study, gold nanoparticles (Au NPs) of average grain diameter of 3 ± 1 nm were prepared using egg white as the reductant. These particles showed no aggregation and pink fluorescence. Au NPs were mixed with gentamicin sulfate (GS) and loaded into a mixture of konjac glucomannan (KGM) and gelatin as wound dressing (KGM/[email protected] NPs/GS). Antibacterial experiments showed that the Au NPs amplified the antibacterial activity of GS; Au NPs/GS efficiently eliminated bacteria, especially super bacteria. Cytotoxicity tests indicated that KGM/[email protected] NPs/GS showed basically no cytotoxicity to L929 cells. In addition, KGM/[email protected] NPs/GS possesses good water absorption, water retention, and enhanced mechanical properties, which can provide a moist environment for wounds and promote healing. In conclusion, our study showed that the antibacterial activity of KGM/[email protected] NPs/GS is better than that of only GS and that it efficiently eliminated super bacteria. Therefore, KGM/[email protected] NPs/GS can be used for killing superbugs, inhibiting bacterial growth, and promoting wound healing.

    更新日期:2020-01-23
  • Effect of pH on the structure and function of pyruvate dehydrogenase kinase 3: Combined spectroscopic and MD simulation studies
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Saleha Anwar; Rajiv K. Kar; Md. Anzarul Haque; Rashmi Dahiya; Preeti Gupta; Asimul Islam; Faizan Ahmad; Md. Imtaiyaz Hassan

    Pyruvate dehydrogenase kinase-3 (PDK3) plays important role in the glucose metabolism, and is associated with cancer progression, and thus being considered as an attractive target for cancer therapy. In this study, we employed spectroscopic techniques to study the structural and conformational changes in the PDK3 at varying pH conditions ranging from pH 2.0 to 12.0. UV/Vis, fluorescence and circular dichroism spectroscopic measurements revealed that PDK3 maintains its native-like structure (both secondary and tertiary) in the alkaline conditions (pH 7.0–12.0). However, a significant loss in the structure was observed under acidic conditions (pH 2.0–6.0). The propensity of aggregate formation at pH 4.0 was estimated by thioflavin T fluorescence measurements. To further complement structural data, kinase activity assay was performed, and maximum activity of PDK3 was observed at pH 7.0–8.0 range; whereas, its activity was lost under acidic pH. To further see conformational changes at atomistic level we have performed all-atom molecular dynamics at different pH conditions for 150 ns. A well defined correlation was observed between experimental and computational studies. This work highlights the significance of structural dependence of pH for wide implications in protein-protein interaction, biological function and drug design procedures.

    更新日期:2020-01-23
  • Succinoglycan dialdehyde-reinforced gelatin hydrogels with toughness and thermal stability
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Seonmok Kim; Daham Jeong; Hyojeong Lee; Dajung Kim; Seunho Jung

    Pure gelatin hydrogel (PG) has limited practical applications due to their thermal instability and unfavorable mechanical properties. To overcome these limitations, dually crosslinked hydrogels were developed by imparting chemical crosslinking to existing physically crosslinked gelatin hydrogel networks using succinoglycan dialdehyde (SGDA) as a macromolecular crosslinker. SGDA-reinforced gelatin hydrogels (SGDA/Gels) displayed an 11 times higher compressive stress under identical deformation strain and a 1040% improvement in storage modulus (G′) than PG. In addition, chemical crosslinking induced by SGDA increased the thermal stability of SGDA/Gels, such that they did not decompose at 60 °C, as confirmed by oscillatory temperature ramp experiments. The newly synthesized SGDA/Gels with reinforced networks and thermal stability exhibit potential for long-term use as controlled drug delivery carriers and 3D cell culture scaffolds for tissue engineering.

    更新日期:2020-01-23
  • Development of Ga-68 labeled, biotinylated thiosemicarbazone dextran-coated iron oxide nanoparticles as multimodal PET/MRI probe
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Nazila Gholipour; Mehdi Akhlaghi; Amin Mokhtari Kheirabadi; Parham Geramifar; Davood Beiki
    更新日期:2020-01-23
  • Fabrication of novel iminodiacetic acid-functionalized carboxymethyl cellulose microbeads for efficient removal of cationic crystal violet dye from aqueous solutions
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-23
    Ahmed M. Omer; Gehad S. Elgarhy; Gehan M. El-Subruiti; Randa E. Khalifa; Abdelazeem S. Eltaweil
    更新日期:2020-01-23
  • Structural and functional relationship of Cassia obtusifolia trypsin inhibitor to understand its digestive resistance against Pieris rapae
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-22
    Jiayu Zhou; Chaolin Li; Anqi Chen; Jianquan Zhu; Meng Zou; Hai Liao; Yamei Yu

    Although digestive resistance of Kunitz protease inhibitors has been reported extensively, the molecular mechanism is not well established. In the present study, the first X-ray structure of Cassia obtusifolia trypsin inhibitor (COTI), a member of Kunitz protease inhibitors, was solved at a resolution of 1.9 Å. The structure adopted a classic β-trefoil fold with the inhibitory loop protruding from the hydrophobic core. The role of Phe139, a unique residue in Kunitz protease inhibitors, and Arg63 in the COTI structure was verified by F139A and R63E mutants. COTI was a specific inhibitor of bovine trypsin and the result was also verified by COTI-trypsin complex formation. Meanwhile, COTI showed equivalent inhibitory activity with that of soybean trypsin inhibitor against bovine trypsin and midgut trypsin from Pieris rapae. The F139 and R63E mutants further indicated that inhibitory specificity and efficiency of COTI were closely related to the global framework, the conformation and the amino acid composition of reactive loop. Finally, a midgut trypsin from P. rapae (PrSP40), which might be involve in the food digestion, was proposed to be a potential target of COTI and might be a promising target for future crop-protection strategy. The results supported the digestive resistance of COTI.

    更新日期:2020-01-22
  • Bacterial cellulose membrane conjugated with plant-derived osteopontin: Preparation and its potential for bone tissue regeneration
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-22
    Nichapa Klinthoopthamrong; Daneeya Chaikiawkeaw; Waranyoo Phoolcharoen; Kaewta Rattanapisit; Pornjira Kaewpungsup; Prasit Pavasant; Voravee P. Hoven

    Bacterial cellulose membrane (BCM) has been recently recognized as a new generation of carbohydrate-based nanomaterial that possesses a great potential in tissue engineering applications. This research aims to develop an active non-resorbable guided tissue regeneration (GTR) membrane from BCM by conjugating with plant-derived recombinant human osteopontin (p-rhOPN), an economically produced and RGD-containing biomolecule. The BCM was initially grafted with poly(acrylic acid) (PAA) brushes to form poly(acrylic acid)-grafted BCM. Multiple carboxyl groups introduced to the BCM by PAA can serve as active anchoring points for p-rhOPN conjugation and yielded p-rhOPN-BCM. All chemically modified BCMs were characterized by attenuated total reflectance Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, while their surface morphology was evaluated by field emission-scanning electron microscopy and atomic force microscopy analyses. The amount of p-rhOPN adhered on the membrane was quantified by enzyme-linked immunosorbent assay. The immunocytochemistry, two-stage quantitative real-time reverse transcriptase polymerase chain reaction and in vitro mineralization analyses strongly suggested that p-rhOPN-BCM could elicit biological functions leading to the enhancement of osteogenic differentiation of human periodontal ligament stem cells as effective as BCM conjugated with commercially available rhOPN from mammalian cells (rhOPN-BCM), suggesting its potential to be used as GTR membrane to promote bone tissue regeneration.

    更新日期:2020-01-22
  • Quantitative phosphoproteomic analysis of fertilized egg derived from Tibetan and lowland chickens
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-22
    Yaping Liu; Ning Qiu; Fang Geng; Haohao Sun; Hong Wang; Yaqi Meng

    In this study, immobilized metal affinity chromatography and ultra-high liquid chromatography tandem mass spectrometry were used to establish detailed phosphoproteomes of fertilized egg, and further quantitative compared those from Tibetan chicken and lowland chicken. A total of 138 phosphosites from 42 phosphoproteins were identified. Specifically, 103 phosphosites representing 41 phosphoproteins were detected in Tibetan chicken egg, and 125 sites in 40 phosphoproteins were found in lowland chicken egg; 47 phosphosites in 26 phosphoproteins were found in fertilized egg white, while 109 phosphosites in 24 phosphoproteins were identified in fertilized egg yolk. Thirty-one phosphoproteins carrying 83 phosphosites (12 phosphosites from 10 phosphoproteins in egg white and 52 sites from 17 proteins in egg yolk) showed significantly different phosphorylation between Tibetan and lowland chicken eggs, which were mainly involved in binding, catalysis, allergenic and cryoprotectant activities. Besides, several amino acid polymorphisms in ovalbumin and vittelligion-2 were detected, which might alter 3D structures and biofunctions. Our data recorded the egg phosphoprotein abundances and biological activities of two chicken species. These results provide a solid foundation to better understand the egg phosphoprotein characteristics, especially to explore the impacts of cross-species alteration of phosphorylation status on the structure, function and nutritional properties.

    更新日期:2020-01-22
  • 更新日期:2020-01-22
  • Removal of Congo red from aqueous solution by adsorption using gum ghatti and acrylamide graft copolymer coated with zero valent iron
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-22
    Goddeti Siva Mohan Reddy; Madhumita Bhaumik; Arjun Maity; Suprakas Sinha Ray

    Gum ghatti (Gg) and acrylamide (AAm) grafted copolymer [poly (Gg-AAm)] coated by zero valent iron (ZVI) was developed to remove toxic Congo red (CR) from waste water. Prepared composite, [poly (Gg-AAm)/ZVI] was characterized by FESEM, TEM, BET, FTIR and XRD. CR adsorption from water using [poly (Gg-AAm)/ZVI] was investigated and several parameters discussed, such as solution pH, contact time, dosage and temperature to find out removal efficiency of polymer composite. The kinetic data for the adsorption of CR followed the pseudo-second-order model and the Langmuir maximum adsorption capacity for CR at pH 7.0 were found to be 153.8, 200 and 250 mg/g at 25, 35 and 45 °C correspondingly. Desorption studies revealed that prepared composite can be used up to three cycles efficiently and thermodynamic parameters such as Gibbs free energy (ΔG0), enthalpy (ΔH0) and entropy (ΔS0) changes showed the adsorption of CR onto [poly (Gg-AAm)/ZVI] was feasible, spontaneous and endothermic.

    更新日期:2020-01-22
  • Encapsulation of phycocyanin by prebiotics and polysaccharides-based electrospun fibers and improved colon cancer prevention effects
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-22
    Yan Wen; Peng Wen; Teng-Gen Hu; Robert J. Linhardt; Min-Hua Zong; Hong Wu; Zhi-Yi Chen

    To preserve bioactivity and achieve colon targeted release of phycocyanin (PC), the polysaccharides-based electrospun fiber mat (EFM) containing PC and prebiotics was prepared and characterized. In vitro release tests confirmed the colon targeting behavior of PC, in particular, faster release of PC was achieved due to the addition of prebiotics. Ritger–Peppas model confirmed that the release of PC in simulated colon fluids follows a mechanism of anomalous transport (non-Fickian). CCK-8 results showed that the combination of PC and prebiotics exerted a significant anti-proliferative effect on HCT116 cells with an IC50 values of 24.17, 19.43 and 12.82 mg/mL after 24, 48, and 72 h, respectively. Furthermore, the cell cycle and apoptosis analysis revealed that the inhibition activity on HCT116 cells was caused by arresting cell cycle at G0/G1 phase that is relevant to the inhibition of cyclin D1 and CDK4 and the up-regulation of p21 expression, and inducing cell apoptosis by mediating the mitochondrial pathway as well, in which the decrease of Bcl-2/Bax, activation of caspase 3 and release of cytochrome c were included. This study suggests that the PC-loaded EFM with GOS holds a great potential as an effective formulation for colon cancer prevention.

    更新日期:2020-01-22
  • A new insight into protein-protein interactions and the effect of conformational alterations in PCNA
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-22
    Vijay Bhardwaj; Rituraj Purohit

    The sliding clamp proteins are present in almost all forms of life and participate in various fundamental processes. Many of these proteins accommodate a conserved sequence that interacts with the hydrophobic groove on sliding clamps. The conserved sequence on proteins is known as the PCNA-interacting protein box, and the hydrophobic groove of PCNA contains regions of the inter-domain connecting loop, the central loop, and amino acids from the C-terminal tail of PCNA. We performed molecular dynamics simulation studies (1.0 μs) to analyze the structural changes at the atomic level in native, C22Y, and C81R mutant PCNA. Our study revealed significant changes at sites responsible for a functional trimeric form of PCNA. This study also unveils the dynamic behavior of IDCL, central loop, and the C-terminal tail, which are essential regions for protein binding with PCNA and the effect of mutations on binding with the Cdc9 peptide. The observation of Cdc9 peptide complexed with native and mutants (C22Y and C81R) structures possibly reveals the mechanism by which PCNA recruits different proteins required for various biological processes and also highlights the importance of dynamic behavior of key regions involved in PCNA protein-protein interactions.

    更新日期:2020-01-22
  • Hypoglycaemic effect and mechanism of an RG-II type polysaccharide purified from Aconitum coreanum in diet-induced obese mice
    Int. J. Biol. Macromol. (IF 4.784) Pub Date : 2020-01-22
    Juan Su; Xinya Liu; Hanqing Li; Xiang Cheng; Songshan Shi; Ning Li; Jianjun Wu; Yongbin Xu; Ruimin Liu; Xueli Tian; Huijun Wang; Shunchun Wang

    The present study aimed to explore the effect of an anti-inflammatory RG-II type polysaccharide (KMPS) purified from Aconitum coreanum (Le'vl.) on glucose metabolism in high-fat diet-induced obese (DIO) mice. Treatment with KMPS for 4 weeks significantly reduced the fasting blood glucose, increased the sensitivity to insulin and improved glucose tolerance. Concurrently, KMPS supplementation also markedly inhibited inflammatory cytokine expression in serum and insulin target tissues and decreased the proportion of M1-type macrophages in adipose tissue, which was considered as the potential hypoglycaemic mechanism. In mechanism study, it was found that KMPS reduced the serine phosphorylation of IRS-1 by inhibiting the activation of the NF-κB pathway, thereby restoring the utilization of glucose by the PI3K/AKT pathway. These results suggested that KMPS may be a potential component for targeting inflammation in the treatment of type 2 diabetes.

    更新日期:2020-01-22
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