In the current research, we have developed silver and iron nanoparticles of isolated proanthocynidin (PAC) from grape seed by green synthesis and evaluated for antimicrobial, antioxidant activity and in vitro cytotoxicity against colon cancer cell lines. One percent solution of isolated proanthocynidin in water was vigorously mixed with 1% silver nitrate and 1% ferric chloride solution and kept for 4 h, to yield PACAgNP and PACFeNP. The synthesized nanoparticles were characterized by UV, FTIR, XRD, and SEM analysis and evaluated for antimicrobial potential against selected microbes. Moreover, the synthesized nanoparticles were studied for DPPH assay and in vitro cytotoxicity using colon cancer cell lines COLO320DM and HT29 (MTT, SRB, and Trypan blue assay). UV spectroscopy confirmed the development of nanoparticles. SEM analysis showed that the particles were aggregated in the size range of 50 to 100 nm. Antimicrobial potential was found to be less against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, whereas cytotoxicity of PACAgNP and PACFeNP against COLO320DM and HT29 exhibited promising results as compared to the pure PAC. PACAgNP and PACFeNP exhibited 20.83 ± 0.33% and 18.06 ± 0.60% inhibition, respectively, against DPPH radical, whereas pure PAC showed 16.79 ± 0.32% inhibition and standard (ascorbic acid) exhibited 98.73 ± 0.18% inhibition of DPPH radical. The silver and iron nanoparticles were successfully developed by green synthesis method using isolated proanthocynidin which is economical and eco-friendly. The use of metal nanoparticles may open up a new opportunity for anticancer therapies to minimize the toxic effects of available anticancer drugs specifically in targeting specific site.

中文翻译：

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分离的原花青素的银和铁纳米粒子的绿色合成：其表征，抗氧化，抗菌和针对COLO320DM和HT29的细胞毒性活性。

在当前的研究中，我们通过绿色合成开发了从葡萄籽中分离的原花青素（PAC）的银和铁纳米粒子，并评估了其对结肠癌细胞系的抗菌，抗氧化活性和体外细胞毒性。将分离的原花青素在水中的1％溶液与1％硝酸银和1％氯化铁溶液剧烈混合，并保持4小时，以产生PACAgNP和PACFeNP。通过UV，FTIR，XRD和SEM分析对合成的纳米颗粒进行表征，并评估其对所选微生物的抗菌潜力。此外，使用结肠癌细胞系COLO320DM和HT29（MTT，SRB和台盼蓝试验）研究了合成的纳米颗粒用于DPPH测定和体外细胞毒性。紫外光谱证实了纳米颗粒的发展。SEM分析表明颗粒聚集在50至100nm的尺寸范围内。发现对金黄色葡萄球菌，铜绿假单胞菌和大肠杆菌的抗菌潜力较小，而与纯PAC相比，PACAgNP和PACFeNP对COLO320DM和HT29的细胞毒性显示出可喜的结果。PACAgNP和PACFeNP对DPPH自由基的抑制分别为20.83±0.33％和18.06±0.60％，而纯PAC对DPPH自由基的抑制为16.79±0.32％，而标准品（抗坏血酸）对DPPH自由基的抑制为98.73±0.18％。使用分离的原花青素通过绿色合成方法成功开发了银和铁纳米颗粒，经济且环保。