OICC Press Journal of Nanostructure in Chemistry 2193-8865 12 3 (June 2022) 2021 07 15 Cytotoxic and antibacterial activities of starch encapsulated photo-catalyzed phytogenic silver nanoparticles from Paeonia lactiflora flowers 10.1007/s40097-021-00421-w EN Yingshan Jin College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, CN Bing Li College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, CN Department of Bio-Health Convergence, College of Biomedical Sciences, Kangwon National University, Chuncheon, 200-701, KR Kandasamy Saravanakumar Department of Bio-Health Convergence, College of Biomedical Sciences, Kangwon National University, Chuncheon, 200-701, KR Xiaowen Hu Department of Bio-Health Convergence, College of Biomedical Sciences, Kangwon National University, Chuncheon, 200-701, KR Arokia Vijaya Anand Mariadoss Department of Bio-Health Convergence, College of Biomedical Sciences, Kangwon National University, Chuncheon, 200-701, KR Myeong-Hyeon Wang Department of Bio-Health Convergence, College of Biomedical Sciences, Kangwon National University, Chuncheon, 200-701, KR Journal Article 2021 07 15 Abstract This work reports the cytotoxic and antibacterial activities of starch encapsulated phytogenic silver nanoparticles synthesized from Paeonia lactiflora flowers (PLF-AgNPs). To optimize the synthesis of AgNPs, a total of 13 reactions were performed with the different combinations of AgNO 3 (1–5 mM), plant extract (5–15% v/v), and light exposure time (0–48 h). The UV-spectrum results indicated that AgNPs were not produced without the light exposure while the light exposure significantly triggered the production of AgNPs. Among the various combination of plant extracts, AgNO 3 concentration, and light exposure, only four combinations were successfully formed the AgNPs and they were named as PLF-AgNPs (1:5:48), PLF-AgNPs (3:5:24), PLF-AgNPs (3:15:3.5), and PLF-AgNPs (3:5:3) according to their ratio of AgNO 3 :plant extract:light exposure time. The physicochemical properties of newly synthesized all the NPs were studied using the various characterization techniques including FTIR, XRD, and FE-TEM, EDS. The encapsulation of the starch was significantly reduced the toxicity of AgNPs in the NIH3T3 cell line and LN229 cell line evidenced by cytotoxicity, AO/EB, and DACF-DA staining assay. Besides, ST-PLF-AgNPs has inhibited the bacterial growth higher than the PLF-AgNPs with MIC of 3.91 ± 0.11, 1.63 ± 0.09, 2.86 ± 0.39, 1.95 ± 0.24 μg/mL for Listeria monocytogenes , Staphylococcus aureus , Escherichia coli, and Salmonella enterica, respectively. The present results proved that encapsulation of the starch reduced the cytotoxicity by increasing the antibacterial activity of ST-PLF-AgNPs, which is deserved for biotherapeutics analysis to treat bacterial infections.