CSIR-Institute of Microbial Technology (IMTECH), Sector-39A, Chandigarh, 160036, India.
Sci Rep. 2020 Jan 29;10(1):1463. doi: 10.1038/s41598-019-57399-3.
Microbes develop several strategies to survive in the adverse condition such as biofilm formation, attaining non-dividing state, altering drug target or drug, thereby increases the burden of drug dosage. To combat these issues, nanoparticles have shown an alternative approach for new treatment strategy but synthesis via chemical synthetic route limits their application in biomedical field. Here, green method for the synthesis of gold nanoparticles using sophorolipid (SL) is discussed that is characterized by various techniques. Initially, the antimicrobial activity was checked against metabolically active state of microbes; Gram-positive Staphylococcus aureus and Gram-negative Vibrio cholerae using XTT assay and growth kinetics assay. Results suggested higher efficacy of nanoparticles for Gram-negative, therefore further analyzed against Escherichia coli that confirmed its potency for the same. AuNPs-SL also signifies its efficiency at least metabolically active state; non dividing cells and biofilm of these microbes. Induced morphological changes were studied by SEM that revealed AuNPs-SL led to disruption of cell membrane and leakage of intracellular fluid to the surroundings. Inhibition of respiratory enzymes activity also plays a crucial role in bactericidal action as indicated by LDH assay. Synergy of AuNPs-SL with different antibiotics was also analyzed using checkerboard assay. These results suggested the possible use of AuNPs-SL as an antimicrobial therapy in the field of nanomedicine.
微生物会发展出几种策略来在逆境中存活，例如形成生物膜、进入非分裂状态、改变药物靶点或药物，从而增加药物剂量的负担。为了解决这些问题，纳米颗粒已经为新的治疗策略提供了一种替代方法，但通过化学合成路线合成限制了它们在生物医学领域的应用。在这里，我们讨论了使用槐糖脂（SL）绿色合成金纳米颗粒的方法，并通过多种技术对其进行了表征。最初，使用 XTT 测定法和生长动力学测定法检查了纳米颗粒对代谢活跃状态的微生物（革兰氏阳性的金黄色葡萄球菌和革兰氏阴性的霍乱弧菌）的抗菌活性。结果表明，纳米颗粒对革兰氏阴性菌的效果更高，因此进一步对大肠杆菌进行了分析，证实了其对大肠杆菌的功效。AuNPs-SL 还表明其在这些微生物的代谢活跃状态、非分裂细胞和生物膜中都具有效率。通过 SEM 研究了诱导的形态变化，结果表明 AuNPs-SL 导致细胞膜破裂，细胞内液泄漏到周围环境中。LDH 测定表明，呼吸酶活性的抑制在杀菌作用中也起着至关重要的作用。还使用棋盘测定法分析了 AuNPs-SL 与不同抗生素的协同作用。这些结果表明，AuNPs-SL 可作为纳米医学领域中的一种抗菌治疗方法。
