Silver nanoparticles (AgNPs) usefulness has been widely demonstrated in fields such as agriculture, medicine, food, and pharmaceutical industries, primarily for their antibacterial properties. AgNPs synthesized from biological extracts are as effective as those obtained by chemical methods, with the advantage that in the former fewer toxic compounds are generated for the environment. In a previous work, we synthesized AgNPs from the aqueous extract of Opuntia ficus-indica fruit peel (OfAgNPs) and tested their activity against microorganisms from a wastewater treatment plant. OfAgNPs were proposed for use as tertiary wastewater treatment; however, more needs to be known about their antimicrobial activity and toxicological potential. In the present study, the antimicrobial effect of OfAgNPs was demonstrated against reference bacterial strains of Escherichia coli (DH5α), Pseudomonas aeruginosa (ATCC 27853), and Staphylococcus aureus (ATCC 29213), and against fungi isolated in the laboratory and identified as Aspergillus sp., Colletotrichum sp., and Cladosporium sp. In addition, in this work, we report the effects of OfAgNPs produced by exposure in two model organisms: a fish, Danio rerio, and a plant, Arabidopsis thaliana. OfAgNPs in A. thaliana caused negative effects on growth and photosynthetic pigment content only when the exposure was constant and greater than 6 mg/L. However, in D. rerio, impaired caudal fin development was observed at 0.15 mg/L from 24 hr of exposure. This is evidence of the toxicological potential of OfAgNPs, so their use should be carried out in a controlled manner.

中文翻译：

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仙人掌合成银纳米粒子对斑马鱼和拟南芥的毒性及其抗菌活性

银纳米粒子 (AgNP) 的用途已在农业、医药、食品和制药工业等领域得到广泛证明，主要是因为其抗菌特性。由生物提取物合成的纳米银颗粒与通过化学方法获得的纳米颗粒一样有效，其优点是前者对环境产生的有毒化合物较少。在之前的工作中，我们从仙人掌水提取物中合成了AgNPs果皮（OfAgNPs）并测试了它们对废水处理厂微生物的活性。提议将AgNPs用作三级废水处理；然而，我们还需要更多地了解它们的抗菌活性和毒理学潜力。在本研究中，OfAgNPs 的抗菌作用得到了证明，可对抗大肠杆菌(DH5 α )、铜绿假单胞菌(ATCC 27853) 和金黄色葡萄球菌(ATCC 29213) 参考菌株，以及实验室分离并鉴定为曲霉菌的真菌sp.、Colletotrichum sp. 和Cladosporiumsp。此外，在这项工作中，我们报告了暴露于两种模型生物（一种鱼（斑马鱼）和一种植物（拟南芥）中的 AgNP 的影响。仅当暴露量恒定且大于 6 mg/L 时，拟南芥中的 AgNP才会对生长和光合色素含量产生负面影响。然而，在斑马鱼中，暴露 24 小时后，在 0.15 mg/L 浓度下观察到尾鳍发育受损。这是 OfAgNP 潜在毒理学的证据，因此应以受控方式使用它们。