The present study aimed in green synthesis and characterization of silver nanoparticles (AgNPs) using the leaves of Cleistanthus collinus. The NPs showed various absorption peaks between 3402 cm⁻¹ and 1063 cm⁻¹. FTIR spectrum revealed the presence of OH group, alkene, aromatic hydrocarbon, aliphatic fluro compound and aliphatic chloro compounds. Scanning electron microscopic analysis revealed the particle size ranged from 30 to 50 nm. The biosynthesized NPs have potent activity against Shigella dysentriae, Staphylococcus aureus and Bacillus subtilis and the zone of inhibition was 21 ± 1, 20 ± 2, 16 ± 2 mm, respectively. Toxicity of the synthesized NPs was tested on green gram (Vigna radiata) seed at various concentrations (20–100%) and germination was induced by NPs treated seeds. Shoot length and root length was higher in NPs treated plant than control plant (p < 0.01). Elevated level of catalase (CAT) and superoxide dismutase (SOD) and about 13% CAT and 7% SOD activity registered than control. Superoxide dismutase activity of root and shoot varied based on the dosage of AgNPs (p < 0.01). Also, the NPs (1%) showed significant larvicidal activity on Aedes aegypti and 100% mortality was achieved after 24 h treatment. The green synthesized NPs reduced methylene blue and 4-nitrophenol significantly (p < 0.01). The colouration of methylene blue and 4-nitrophenol were considerably reduced after 60 min showed the potential of dye degrading ability.

本研究旨在利用Cleistanthus collinus的叶子来绿色合成和表征银纳米颗粒 (AgNP)。 NPs在3402cm ^-1和1063cm ^-1之间显示出不同的吸收峰。 FTIR光谱显示存在OH基团、烯烃、芳香烃、脂肪族氟化合物和脂肪族氯化合物。扫描电子显微镜分析显示颗粒尺寸范围为 30 至 50 nm。生物合成的纳米颗粒对痢疾志贺氏菌、金黄色葡萄球菌和枯草芽孢杆菌具有有效的活性，抑制范围分别为21±1、20±2、16±2mm。在不同浓度 ( 20-100 %) 的绿豆种子上测试了合成的 NP 的毒性，并通过 NP 处理的种子诱导发芽。经 NP 处理的植物的芽长和根长高于对照植物 (p < 0.01)。与对照相比，过氧化氢酶 (CAT) 和超氧化物歧化酶 (SOD) 水平升高，CAT 活性提高约 13%，SOD 活性提高约 7%。根和芽的超氧化物歧化酶活性根据 AgNP 的剂量而变化 (p < 0.01)。此外，NPs (1%) 对埃及伊蚊表现出显着的杀幼虫活性，处理 24 小时后死亡率达到 100%。绿色合成的纳米颗粒显着减少亚甲基蓝和 4-硝基苯酚 (p < 0.01)。 60分钟后亚甲基蓝和4-硝基苯酚的着色显着降低，显示出潜在的染料降解能力。