Excessive use of antibiotics has led to the emergence of multidrug-resistant bacteria that are a serious threat to human health. There is a need to develop efficient antibacterial agents to address this problem. Tannins are high molecular weight (MW) polyphenols (500−30,000 Da), distributed throughout the plant kingdom. Tannins are one of the major compounds in plants with potential health benefits. This review addresses the antibacterial and antivirulence effects of different types of tannins and highlights the underlying antibacterial mechanisms of action. Furthermore, an overview of the antibacterial effects of emerging tannin-loaded nanoparticles/hydrogels is presented. Tannins have been found to inhibit bacterial growth using different mechanisms of action including iron chelation, inhibition of cell wall synthesis, disruption of the cell membrane, and inhibition of fatty acid biosynthetic pathways. Tannins can act as quorum sensing inhibitors and attenuate the gene expression of several virulence factors such as biofilms, enzymes, adhesins, motility, and toxins. Also, tannin-loaded nanoparticles/hydrogels show good antibacterial effects. Overall, tannins may be promising antibacterial and antivirulence agents for preventing bacterial infections.

过量使用抗生素已导致对人类健康构成严重威胁的耐多药细菌的出现。需要开发有效的抗菌剂以解决该问题。单宁是高分子量（MW）多酚（500-30,000 Da），分布在整个植物界。单宁酸是植物中具有潜在健康益处的主要化合物之一。这项审查解决了不同类型的单宁的抗菌和抗毒作用，并强调了潜在的抗菌作用机制。此外，概述了新兴的单宁负载纳米颗粒/水凝胶的抗菌作用。已发现单宁可以使用不同的作用机制来抑制细菌生长，包括铁螯合，抑制细胞壁合成，细胞膜的破坏，以及脂肪酸生物合成途径的抑制。单宁可以充当群体感应抑制剂，并减弱几种毒力因子的基因表达，例如生物膜，酶，粘附素，运动性和毒素。同样，单宁负载的纳米颗粒/水凝胶显示出良好的抗菌效果。总体而言，单宁可能是有望预防细菌感染的抗菌和抗毒剂。