绿色合成桑叶银纳米粒及其抗菌抗癌活性

Green synthesis of silver nanoparticles with aqueous Folium Morin extracts and their antimicrobial and anticancer activities

摘要:

为了更好地开发出具有良好物理化学及生物活性的银纳米粒，利用桑叶水提取物，通过绿色方法制得桑叶银纳米粒。以AgNO3浓度、反应温度、桑叶水提物的用量、pH以及反应时间为影响因素，优化桑叶银纳米粒最佳合成条件；通过UV-Vis，SEM及FTIR等对产物进行结构表征；通过测定抑菌圈、最小抑菌浓度和细胞毒实验评价其抗菌及抗癌活性。结果显示，最佳制备条件为：AgNO3浓度5 mmol/L、反应温度35 ℃、桑叶水提液与AgNO3溶液体积比1∶5、反应体系pH 11.0及反应时间6 h。在此条件下制备的桑叶银纳米粒为大小均一的球形，平均粒径（48.78 ± 0.39） nm，电位（-27.8 ± 2.00） mV；相比于桑叶水提物，桑叶银纳米粒对大肠杆菌、铜绿假单胞菌，金黄色葡萄球菌、枯草杆菌及白色念球菌均表现较好的抑菌效果，其最小抑菌浓度分别为12.50、25.00、25.00、100.00和100.00 mg/L；桑叶银纳米粒对人宫颈癌（IC50为60.63 mg/L），人肝癌（IC50为 26.98 mg/L）和人乳腺癌（IC50为18.65 mg/L）细胞有很好的抑制作用。

Abstract:

To better develop silver nanoparticles with good physicochemical properties and bioactivities. Mulberry leaves silver nanoparticles (ML-AgNPs) were prepared from aqueous mulberry leaves extracts (MLE) by green synthesis method. The factors affecting the formation of ML-AgNPs such as concentration of AgNO3 solution, reaction temperature, volume ratio of MLE solution to AgNO3 solution, pH of MLE solution and reaction time were investigated. The products were characterized by UV-Vis, SEM and FTIR. The antimicrobial activities of ML-AgNPs were assessed by determining the inhibition zone and minimum inhibitory concentration (MIC) values, and their anticancer activities were evaluated by cell cytotoxicity assay. The results showed that the optimal conditions for the synthesis of ML-AgNPs were as follows: AgNO3 concentration 5.0 mmol/L, V(MLE)∶V(AgNO3 solution)=1∶5, reaction temperature 35 ℃, pH of MLE solution 11.0, and reaction time 6 h. Under the above-mentioned conditions, the synthesized ML-AgNPs were spherical with an average particle size (48.78 ± 0.39) nm and low surface potential (-27.8 ± 2.00) mV. Compared with MLE, ML-AgNPs showed excellent antimicrobial activities against E. coli, P. aeruginosa, S. aureus, B. subtilis and C. albicans with corresponding MIC values of 12.50, 25.00, 25.00, 100.00 and 100.00 mg/L. Moreover, ML-AgNPs exhibited good anticancer activities against Hela, HepG2 and MCF-7 cell lines with IC50 of 60.63, 26.98 and 18.65 mg/L, respectively.