Nanoparticles (NPs) have gained importance in technological advances owing to their user friendly enhanced and efficient physical, chemical, and biological characteristics compared to their bulk counterparts. Biological synthesis of NPs by using a microorganism, enzymes, or plant extracts offers a greener and eco-friendly approach besides many advantages over physical or chemical approaches. This study reports the biosynthesis of silver nanoparticles (AgNPs) using Nostoc muscorum NCCU 442 aqueous extract as the reducing and capping agent for AgNPs synthesis. The synthesized nanoparticles were characterized by UV‐VIS spectrum, SEM, EDS, TEM, AFM, DLS and XRD. Results showed distinguishing polycrystalline nature of synthesized AgNPs with surface plasmon significant band in the size range of 6‐45nm with average 30 size nm. FT-IR study revealed the role of secondary metabolites present in aqueous extract for the synthesis of AgNPs. Biological activities of purified AgNPs as antioxidant and antibacterial potential showed the highest antibacterial activity against Staphylococcus aureus MTCC 902.

纳米颗粒（NPs）由于其用户友好的增强的，高效的物理，化学和生物学特性，而在其技术进步中变得越来越重要。通过使用微生物，酶或植物提取物生物合成NP不仅提供了比物理或化学方法更多的优势，而且提供了一种绿色环保的方法。这项研究报告了使用Nostoc muscorum NCCU 442的银纳米颗粒（AgNPs）的生物合成水提取物作为AgNP合成的还原和封端剂。通过UV-VIS光谱，SEM，EDS，TEM，AFM，DLS和XRD表征了合成的纳米颗粒。结果显示，合成的AgNP具有明显的多晶性质，其表面等离激元显着带在6-45nm的范围内，平均30纳米。FT-IR研究揭示了水提取物中存在的次级代谢产物对于合成AgNPs的作用。纯化的AgNPs的生物活性作为抗氧化性和抗菌潜力对金黄色葡萄球菌MTCC 902具有最高的抗菌活性。