Abstract Pterostilbene (PTE), a dimethylated analogue of resveratrol, mostly contained in Vitis vinifera leaves or in other plant sources is well-known for its antioxidant activity. Due to its bioavailability, low hydrophilicity and thus ability to penetrate hydrophobic biological membranes it was found to be an antimicrobial agent. These properties of PTE offer the possibility of its use in the treatment of microbial infections. The emergence of antibiotic resistance of microorganisms is often caused by their ability to form biofilm; new substances with antibiofilm activity are therefore sought. The representatives of opportunistic pathogenic gram-positive and gram-negative bacteria as well as fungi were used for the determination of minimum inhibitory concentrations (MIC 50 and MIC 80 ), minimum biofilm inhibitory concentrations (MBIC 50 and MBIC 80 ) and minimum biofilm eradication concentrations (MBEC 50 and MBEC 80 ) of PTE and commonly used antibiotics erythromycin, polymyxin B or antimycotic amphotericin B. Total biofilm biomass was investigated by crystal violet staining, and the results were confirmed using microscopic techniques. The most significant antibiofilm action was proved for gram-positive cocci, e.g., MBEC 50 of PTE for all strains of Staphylococcus epidermidis tested was 25 mg/L. By contrast, the antibiotic ERM did not exhibit antibiofilm activity in most cases. The permeabilization of cell membranes of gram-positive cocci biofilm by MBIC 50 and MBEC 50 of PTE was confirmed by LIVE/DEAD staining using spinning disc confocal microscopy. PTE significantly influenced the ability of gram-positive cocci to form biofilm and it effectively eradicated pre-formed biofilm in vitro; its potential for the treatment of biofilm-associated infections of Staphylococcus spp. or Enterococcus faecalis is thus apparent. Graphic abstract

中文翻译：

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天然抗氧化剂紫檀芪作为一种有效的抗生物膜剂，特别是对于革兰氏阳性球菌

摘要紫檀芪 (PTE) 是白藜芦醇的二甲基化类似物，主要存在于葡萄叶或其他植物来源中，以其抗氧化活性而闻名。由于它的生物利用度、低亲水性和渗透疏水生物膜的能力，它被发现是一种抗微生物剂。PTE 的这些特性为其用于治疗微生物感染提供了可能性。微生物对抗生素耐药性的出现，往往是由于它们具有形成生物膜的能力；因此寻求具有抗生物膜活性的新物质。机会致病性革兰氏阳性菌和革兰氏阴性菌以及真菌的代表用于测定最低抑菌浓度（MIC 50 和MIC 80 ），PTE 和常用抗生素红霉素、多粘菌素 B 或抗真菌两性霉素 B 的最小生物膜抑制浓度（MBIC 50 和 MBIC 80 ）和最小生物膜根除浓度（MBEC 50 和 MBEC 80 ）。通过结晶紫染色研究总生物膜生物量，以及使用显微技术证实了结果。证明对革兰氏阳性球菌具有最显着的抗生物膜作用，例如，对于所有测试的表皮葡萄球菌菌株，PTE 的 MBEC 50 为 25 mg/L。相比之下，抗生素 ERM 在大多数情况下没有表现出抗生物膜活性。PTE 的 MBIC 50 和 MBEC 50 对革兰氏阳性球菌生物膜细胞膜的透化作用通过使用转盘共聚焦显微镜的 LIVE/DEAD 染色得到证实。PTE显着影响革兰氏阳性球菌形成生物膜的能力，并在体外有效根除预先形成的生物膜；其治疗葡萄球菌属生物膜相关感染的潜力。或粪肠球菌因此很明显。图形摘要