Research On The Medicinal Value Of Gallic Acid

Gallic acid (GA), also known as tannin or tannic acid and Gallic, is a colorlesscrystalline, which widely exists in a variety of fruits, teas, Oak bark, and gall asa formof tannin in the nature.GA is one kind of natural compounds which exhibited various biological activities,such as antitumor, antibacterial, antioxidation and anti-inflammatory. Especially, theantitumor activity has attracted wide attention of researchers. Cyclophosphamide(CTX), as one of the most commonly used chemical drugs for malignancy therapy,induces liver and kidney toxicities, and immune function decrease etc. similarly asanother chemotherapy small molecule drugs. In this thesis, the improving efficacy andreducing toxicity properties of GA were confirmed by the combination therapy of GAand CTX toward H22xenografted ICR mice.In the first part of this thesis, the GA metabolism in rat plasma was mainlydetermined by high-performance liquid chromatography. The results indicated thatGA metabolism in rat plasma showed a two-compartment model, and the absolutebioavailability was calculated to be F=17.8213, when the GA was intragastricallyadministered100mg/kg·bw. The pharmacokinetic study result and relatively highbioavailability laied a good experimental and theoretical foundations for the furtherresearch of the GA’s medicinal value.In the second part of this thesis,the improved efficacy and reduced toxicity ofCTX toward the therapy of H22xenografted mice through the combination with GAwere mainly researched. The H22xenoimplanted ICR mice were used asexperimental animal model, and the treatment was performed after randomization.The results revealed that the antitumor efficacy toward the tumor of mouse wasabsolutely improved the combination administration of CTX and GA, and the value ofq was more than1.15after treated with CTX combinated with both high and middlelevel of GA. Therefore, the joint application of CTX and GA presented synergistic effect to tumor inhibition. For reducing toxicity, the presence of GA reduced thenumber of bone marrow micronucleus of tumor xenografted mice in some extent afterchemotherapy with CTX. Thence, the administration with GA could relieve theside-effects of CTX after chemotherapy. This study provided the basis and foundationfor expanding the medicinal valueof GA.In addition, the antibacterial property of GA was studied through disk diffusionmethod against Staphylococcus aureus, Salmonella enteritidis, Escherichia coli,Salmonella typhimurium, Bacillus cereus and Candida albicans. The experimentconfirmed that the GAwith different concentrations performed certain antimicrobialeffect toward Staphylococcus aureus, Salmonella enteritidis, Escherichia coli andSalmonella typhimurium.Through the systemic research, the GA exhibited some medicinal value and thedevelopment prospect was relatively broad. Furthermore, several studies in this thesishave provided certain theory basis and the foundation for the further GA research.