Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea.
Dept. of Zoology, Kundavai Nachiyar Government Arts College for Women (Autonomous), Thanjavur, 613007, Tamil Nadu, India.
Microb Pathog. 2019 Jul;132:66-72. doi: 10.1016/j.micpath.2019.04.035. Epub 2019 Apr 24.
Biosurfactants are surface-active compounds that display a range of physiological functions. The present study investigated the antioxidant, antimicrobial, and anti-adhesive or anti-biofilm potential of biosurfactants isolated from Bacillus subtilis VSG4 and Bacillus licheniformis VS16. The antioxidant activity of the biosurfactants was studied in vitro using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals. At 5 mg/mL of the biosurfactant concentration, the scavenging of DPPH and hydroxyl radicals was found to be between 69.1-73.5% and 63.3-69.8%, respectively. The biosurfactants also displayed significant antibacterial activities against both Gram-positive and Gram-negative bacteria. The anti-adhesive activities of the biosurfactants were evaluated against Staphylococcus aureus ATCC 29523, Salmonella typhimurium ATCC 19430, and Bacillus cereus ATCC 11778. The biosurfactants exhibited anti-adhesive activity, even at concentrations of 3-5 mg/mL. Moreover, both biosurfactants displayed notable anti-biofilm activities with a biofilm eradication percentage ranging from 63.9 to 80.03% for VSG4 biosurfactant, and from 61.1-68.4% for VS16 biosurfactant. Furthermore, VSG4 biosurfactant exhibited emulsification and surface tension stability over a wide range of pH (4-10) and temperature up to 100 °C. These results show that VSG4 and VS16 biosurfactants can be potentially used as natural antioxidants, antimicrobials, and/or anti-adhesive agents for food and biomedical applications.
生物表面活性剂是具有多种生理功能的表面活性化合物。本研究调查了从枯草芽孢杆菌 VSG4 和地衣芽孢杆菌 VS16 中分离的生物表面活性剂的抗氧化、抗菌、抗黏附和抗生物膜潜力。通过 2,2-二苯基-1-苦基肼基（DPPH）和羟基自由基体外研究了生物表面活性剂的抗氧化活性。在 5mg/mL 的生物表面活性剂浓度下，发现 DPPH 和羟基自由基的清除率分别为 69.1-73.5%和 63.3-69.8%。生物表面活性剂还对革兰氏阳性和革兰氏阴性细菌表现出显著的抗菌活性。评估了生物表面活性剂对金黄色葡萄球菌 ATCC 29523、鼠伤寒沙门氏菌 ATCC 19430 和蜡状芽孢杆菌 ATCC 11778 的抗黏附活性。生物表面活性剂甚至在 3-5mg/mL 的浓度下也表现出抗黏附活性。此外，两种生物表面活性剂都表现出显著的抗生物膜活性，VSG4 生物表面活性剂的生物膜消除率为 63.9-80.03%，VS16 生物表面活性剂的生物膜消除率为 61.1-68.4%。此外，VSG4 生物表面活性剂在 pH（4-10）和温度高达 100°C 的宽范围内表现出乳化和表面张力稳定性。这些结果表明，VSG4 和 VS16 生物表面活性剂可潜在用作食品和生物医学应用中的天然抗氧化剂、抗菌剂和/或抗黏附剂。
