当前位置: X-MOL 学术Food Funct. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Sonochemical effects on the structure and antioxidant activity of egg white protein-tea polyphenol conjugates.
Food & Function ( IF 5.1 ) Pub Date : 2020-07-29 , DOI: 10.1039/d0fo01636e
Hui Jing 1 , Jun Sun , Yaoyao Mu , Mohammed Obadi , David Julian McClements , Bin Xu
Affiliation  

The antioxidant properties of proteins could be enhanced by forming covalent conjugates with polyphenols. In this study, the antioxidant activity of egg white protein (EWP) was improved by conjugating with tea polyphenols (TP) using traditional and ultrasound-assisted alkaline/free radical methods. In addition, the influences of TP conjugation on the antioxidant activities and structural and digestive properties of EWP were comprehensively studied. Compared with the traditional methods, the sonochemistry (40 kHz) approaches significantly increased the efficiency of TP grafting to the EWP (P < 0.05) from 24 h to 1 h. Amino acid analysis showed that in the ultrasound-assisted alkaline method, TP was successfully conjugated to the EWP through proline, glutamic acid, cysteine, and tryptophan residues, whereas proline, cysteine, and tryptophan were involved in the free radical method. However, the number of cross-linking sites was increased significantly after ultrasound-assisted treatments. Moreover, the antioxidant activities of the EWP were significantly improved after covalent conjugation with TP using traditional and ultrasound-assisted alkaline/free radical methods, particularly the ultrasound-assisted approaches. Furthermore, circular dichroism revealed that the ultrasound-assisted approaches had the greatest impact with regard to decreasing the α-helix content and increasing the random coil content, which loosened the protein structure, thereby improving its reactivity and digestibility. Therefore, ultrasound-assisted alkaline/free radical methods were efficient and safe means for the production of EWP–TP conjugates.

中文翻译:

声化学对蛋清蛋白-茶多酚偶联物的结构和抗氧化活性的影响。

通过与多酚形成共价结合物,可以增强蛋白质的抗氧化性能。在这项研究中,通过使用传统的和超声辅助的碱/自由基方法与茶多酚(TP)结合,可以提高蛋清蛋白(EWP)的抗氧化活性。此外,还全面研究了TP共轭对EWP的抗氧化活性以及结构和消化特性的影响。与传统方法相比,声化学(40 kHz)方法显着提高了TP接枝到EWP(P<0.05)从24小时到1小时。氨基酸分析表明,在超声辅助碱法中,TP通过脯氨酸,谷氨酸,半胱氨酸和色氨酸残基成功结合到EWP上,而脯氨酸,半胱氨酸和色氨酸则通过自由基方法成功结合到EWP上。然而,在超声辅助治疗后,交联位点的数量显着增加。此外,使用传统的和超声辅助的碱/自由基方法(尤其是超声辅助的方法)与TP共价缀合后,EWP的抗氧化活性得到了显着改善。此外,圆二色性表明,超声辅助方法在降低α-螺旋含量和增加随机线圈含量方面影响最大,从而使蛋白质结构松散,从而改善其反应性和消化率。因此,超声辅助碱/自由基方法是生产EWP-TP共轭物的有效和安全的方法。
更新日期:2020-08-19
down
wechat
bug