茶多酚金属络合物的制备及其抑菌活性

Preparation and Bacteriostatic Activity of Tea Polyphenol-Metal Complexes

以茶多酚镉(TP-Cd)络合物的制备工艺为例,对反应温度、时间、pH和TP/Cd^2+摩尔比等茶多酚金属络合物的制备工艺进行了研究,在此基础上制备了TP-Cd、TP-Cu、TP-Zn、TP-Fe(Ⅲ)、TP-Al、TP-Mn、TP-K、TP-Ca、TP-Se、TP-Cr、TP-W、TP-Pb 12种金属离子络合物,并比较了这些络合物对金黄色葡萄球菌和软腐病菌的抑菌活性。结果表明,制备TP-Cd络合物的最佳工艺参数为:TP/Cd^(2+)摩尔比1∶1,pH6.5,30℃下反应30 min;在此条件下,茶多酚沉淀率最高为93.91%。除Se^4+、K^+外,TP与大多数金属离子络合后,对金黄色葡萄球菌的抑菌活性均增强,其抑菌能力大小为TP-Cu>TP-Cd>TP-Zn>TP-Pb>TP-Mn>TP-W≈TP-Al>TP-Fe(Ⅲ)>TP-Cr≈TP-Ca>TP;TP仅与Cu^2+、Cd^2+、Zn^2+、Se^4+、Mn^2+络合后对软腐病菌的抑菌活性显著增强,其抑菌能力大小为TP-Cu≈TP-Cd>TP-Zn>TP-Se>TP-Mn>TP,TP与Pb^2+、Cr^2+络合后其抗真菌活性完全丧失。可见,金属离子与TP络合后影响了TP的抑菌活性,其中以TP-Cu、TP-Cd和TP-Zn的抑菌活性最强。Cu^2+、Cd^2+和Zn^2+等离子与TP络合后,不仅能显著增强TP的抑菌活性,还能有效减轻它们的毒副作用,为开发、利用安全高效的新型抑菌药物提供理论依据,也为茶资源的综合利用提供了新的思路。

The preparation process of the tea polyphenol-metal complexes was studied based on the preparation technology of tea polyphenol-cadmium(TP-Cd)complex,such as reaction temperature,time,pH and molar ratio.On this basis,12 kinds of metal ion complexes of TP-Cd,TP-Cu,TP-Zn,TP-Fe(Ⅲ),TP-Al,TP-Mn,TP-K,TP-Ca,TP-Se,TP-Cr,TP-W,TP-Pb were prepared,and the antibacterial activity of these complexes on Staphylococcus aureus and Rhizopus stolonifera was compared.The results showed that the optimal technological parameters for the preparation of tea polyphenol-cadmium complex were:TP/Cd^2+molar ratio 1∶1,pH6.5,reaction at 30℃,for 30 min.Under this condition,the rate of tea polyphenols precipitation was the highest at 93.91%.With the exception of Se 4+and K+,tea polyphenols complexed with most metal ions,the antimicrobial activity against Staphylococcus aureus was enhanced,and its bacteriostatic capacity was TP-Cu>TP-Cd>TP-Zn>TP-Pb>TP-Mn>TP-W≈TP-Al>TP-Fe(Ⅲ)>TP-Cr≈TP-Ca>TP.The antifungal activity of tea polyphenols was significantly enhanced after complexation only with Cu^2+、Cd^2+、Zn^2+、Se^4+and Mn^2+,and its bacterio-static capacity of Rhizopus stolonifera was TP-Cu≈TP-Cd>TP-Zn>TP-Se>TP-Mn>TP,tea polyphenols was completely lost after complexation with Pb^2+and Cr^2+.It could be seen that the inhibitory activity of tea polyphenols was affected by the com-bination of metal ions with tea polyphenols,among which TP-Cu,TP-Cd and TP-Zn had the strongest bacteriostatic activity.After complexation of Cu^2+,Cd^2+,Zn^2+plasma with tea polyphenols,it couldn’t only significantly enhance the bacteriostatic activity of tea polyphenols,but also effectively reduce their side effects,which provided a theoretical basis of the development and utilization of safe and efficient new bacteriostatic drugs,and a new idea for the comprehensive utilization of tea resources.