Department of Surgery, Jinan Municipal Hospital of Traditional Chinese Medicine, Jinan 250012, China.
Department of Pharmacy, Binzhou Central Hospital of Shandong, Shandong 251700, China.
J Nanosci Nanotechnol. 2019 Jul 1;19(7):4109-4115. doi: 10.1166/jnn.2019.16282.
This study reports the biosynthesis of silver nanoparticles (AgNPs) using methanolic leaf extract of Benth. (Patchouli) as a reducing agent, and their potent biological (antibacterial, antioxidant and anticancer) activities. The extract when exposed to silver nitrate reduced silver ions to form crystalline AgNPs within 1 h of incubation at room-temperature. UV-visible spectra showed a sharp surface plasmon resonance (SPR) at around 430 nm for the biosynthesized AgNPs and the XRD pattern indicated the crystalline planes of the face centered cubic silver. The FE-SEM analysis revealed the occurrence of predominant spherical shaped AgNPs with a huge disparity in their particle size distribution with an average size of 25 nm, while, the FTIR data confirmed the bio-reduction and capping of AgNPs by several phytocompounds present in the methanolic leaf extract. AgNPs effectively inhibited the growth of all the tested human pathogenic bacterial strains (, and ), while, the methanolic leaf extract failed to inhibit the growth of and . AgNPs showed the highest free radical scavenging activity (79.0 ± 0.76%) compared to methanolic leaf extract (68.3 ± 0.68%) at 100 g/ml. Further, the cytotoxicity study using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) confirmed that AgNPs successfully inhibited the human colon adenocarcinoma cell line (HT-29) in a dose dependent manner. At higher concentrations (500 g/ml), only 4% of cells survived after 72 hrs of exposure with IC value of 120 g/ml. Thus, these findings offer a new source of biomolecules with diverse biological activities.
本研究报告了使用 Benth.（广藿香）甲醇叶提取物作为还原剂合成银纳米粒子（AgNPs）及其潜在的生物学（抗菌、抗氧化和抗癌）活性。在室温下孵育 1 小时内，提取物暴露于硝酸银中，将银离子还原为晶态 AgNPs。紫外-可见光谱在 430nm 左右显示出尖锐的表面等离子体共振（SPR），表明合成的 AgNPs 的存在，XRD 图案表明了面心立方银的晶面。FE-SEM 分析表明，AgNPs 主要以球形存在，其粒径分布差异很大，平均粒径为 25nm，而 FTIR 数据证实了 AgNPs 的生物还原和由甲醇叶提取物中存在的几种植物化合物的帽化。AgNPs 有效地抑制了所有测试的人类致病菌株（、和）的生长，而甲醇叶提取物未能抑制和的生长。AgNPs 的自由基清除活性最高（79.0±0.76%），与甲醇叶提取物（68.3±0.68%）相比，在 100g/ml 时。此外，使用 3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四氮唑溴盐（MTT）的细胞毒性研究证实，AgNPs 以剂量依赖的方式成功抑制人结肠腺癌细胞系（HT-29）。在较高浓度（500g/ml）下，暴露 72 小时后，只有 4%的细胞存活，IC 值为 120g/ml。因此，这些发现为具有多种生物学活性的生物分子提供了新的来源。
