纳米银/聚乙烯醇复合物的生物合成及其对6种水产病原菌的抑菌活性

纳米银作为一种新型抑菌剂有望成为传统抑菌剂的替代品，制备稳定、高效、环保的新型纳米银抑菌产品成为当今的研究热点。本研究以葡萄籽提取液为还原剂和稳定剂，聚乙烯醇(PVA)为载体，采用一步法“绿色”生物合成出一种纳米银/聚乙烯醇复合物(AgNPs/PVA)。通过紫外-可见(UV-Vis)吸收光谱、透射电镜(TEM)、X射线衍射(XRD)等手段对合成产物进行了表征。结果表明银离子被葡萄籽提取物成功还原成纳米银并附着在PVA的表面，纳米银颗粒均匀，呈现单分散状态，粒径较小，平均粒径为14 nm左右。AgNPs/PVA对鳗弧菌、溶藻弧菌、副溶血弧菌、哈维氏弧菌、灿烂弧菌及点状气单胞菌等6种典型的水产病原菌均有显著的抑菌效果。以溶藻弧菌为指示菌，AgNPs/PVA的最小抑菌浓度(MIC)为1.1 μg/mL，最小杀菌浓度(MBC)为2.2 μg/mL。AgNPs/PVA的Zeta电位为?24.1 mV，表明纳米银颗粒间有很强的排斥力，为其稳定分散提供保障，后续实验证明制备的AgNPs/PVA具有良好的稳定性和热稳定性。以上研究结果表明，AgNPs/PVA复合材料在水产养殖病害防治中具有广阔的应用前景。 

Biosynthesis of silver nanoparticles/polyvinyl alcohol composite and its antibacterial activity against six aquatic pathogens

As a new generation of antibacterial agent, silver nanoparticles are expected to be a substitute for traditional antibacterial agents in the future. Developing a new stable, efficient and eco-friendly nano-silver antibacterial agent has become the hot spot of current research. In this study, the grape seeds extract was used as an reducing and stabilizing agent, and polyvinyl alcohol (PVA) was used as the carrier, the silver nanoparticles/polyvinyl alcohol (AgNPs/PVA) composites were prepared by a facile, green, “one-pot” biological method. The asprepared AgNPs/PVA composites were characterized by UV absorption spectroscopy (UV-Vis), transmission electron transmission electron microscopy (TEM) and X ray diffraction (XRD). The results indicate that the silver ions are successfully reduced by the grade seeds extract and the produced AgNPs are decorated on the surface of PVA. The AgNPs are uniform and monodisperse, the particle size is small with mean diameter about 14 nm. The AgNPs/PVA composites show superior antibacterial effects against six tipical aquatic pathogens, such as Vibrio splendidus, V. harveyi, V. anguillarum, V. alginolyticus, V. parahaemolyticus and Aeromonas punctata. They have a minimum inhibitory concentration (MIC) of 1.1 μg/mL and a minimum inhibitory concentration (MBC) of 2.2 μg/mL against V. alginolyticus. The Zeta potential of AgNPs/PVA is found to be ?24.1 mV, indicating that the strong repulsion between the nanoparticles, which provide guarantee for stable dispersion. The subsequent experiments prove that the prepared AgNPs/PVA has good stability and thermostability. The above research results indicate that AgNPs/PVA composites have a great application prospect in the control of aquaculture diseases.