Study On The Synthesis Of Dihydromyricetin-zinc(â…¡) Complexes And Biological Activity

Dihydromyricetin (DMY) is the main component of ampelopsis grossedentata, belonging the category of dihydrogen flavonols. It has many physiological activities including anti-inflammatory, analgesic, broad-spectrum anti-bacterial, anti-tumor and anti-oxidation etc. DMY has the structure of ultra-delocalization and π-conjugated bond system leading to the strong chelation with metals, In addition to the inherent physiological activities, some new physiological activities may appear for trace metals chelated with DMY. Zinc is the essential element that makes up a variety of proteins involved in almost all of the metabolism of cells. Zinc can affect the body’s immune system, enhance resistance effect, inhibit the generation of hydroxyl radicals. In the present work, we study the optimum condition for the synthesis of DMY-Zn(II) complex, and the structure was characterized by the technology method. The stability, antioxidant, antibacterial and antitumor effects of DMY-Zn(II) complexes are studied. The main results and conclusions of this study were described as follows:l.The complex of DMY-Zn(II) was synthesized at the condition of70℃, pH=7.5,reaction time6hours, with the yield of83.26%. The most possible structure of complex is [C15H10O8Zn·2H2O] by the methods of UV-visible spectrum, FT-IR, element analysis and TG-DTA. And the stability of DMY-Zn(II) complex are studied. The results show that DMY-Zn(II) complex are stable in weak alkaline environment,and in less than100℃and under the heating conditions with no more than30min.2. The free radical (DPPH,OH,O2) scavenging activities of the DMY-Zn(II) complex were investigated. The results showed that the free radical scavenging activities of the complex on OH,02-, and DPPH-were obviously stronger than that of DMY.3. The antimicrobial activitives of DMY and complex were studied by filter paper method and tube double dilution method. The result showed that both DMY and DMY-Zn(II) complex showed antimicrobial activitives to Escherichia coli, Staphylococcus aureus, Salmonella, but it is not antimicrobial activitives to Vibrion.The complex showed stronger antimicrobial activitives to Escherichia coli, Staphylococcus aureus, Salmonella than DM Y.4. The study of the antitumor activity of DMY and complex on HepG2cell were investigated by MTT methods. The result showed that the proliferation of DMY-Zn(II) on HepG2cell was not significant, contrasting with the doxorubicin, paclitaxel. cisplatin and DMY., but presenting a significant dose-dependent manner.