6种茶类多酚含量测定及其抑菌活性

Detection of Polyphenol Content and Antimicrobial Activity of Six Types of Tea

目的测定绿茶、黄茶、白茶、青茶、红茶、黑茶中多酚的含量,研究其抑菌活性。方法针对6种茶叶样品采用超声波提取法,并经乙酸乙酯提取后,所得供试品溶液依国标法测定多酚含量。并以大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌、蜡样芽孢杆菌为实验菌株,通过圆形滤纸片扩散法研究不同浓度供试品溶液的抑菌活性。结果 6种茶叶样品乙酸乙酯部位多酚得率分别为绿茶59.07%、黄茶62.39%、白茶32.15%、青茶50.70%、红茶34.86%、黑茶40.68%。对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌、蜡样芽孢杆菌的抑菌效果均与供试品溶液浓度呈正相关。结论 6种茶发酵程度的差异导致所含成分不同,致使其抑菌活性有明显区别。

Objective To determine the content and antimicrobial activity of polyphenols from green tea,yellow tea,white tea,oolong tea,black tea and dark green tea.Methods The ultrasonic technology was used for extraction of crude polyphenols from six types of tea,then ethyl acetate was used for the purification,and the contents of polyphenols were detected according to GB/T 8313-2008.Escherichia coli,Staphylococcus aureus,Bacillus subtilis and Bacillus cereus were selected as the test strains.The filter paper disc diffusion method was employed to determine the antibacterial activities of extract solutions in vitro.Results The yields of polyphenols in ethyl acetate extraction were 59.07 ％ for green tea,62.39 ％ for yellow tea,32.15 ％ for white tea,50.70 ％ for oolong tea,34.86 ％ for black tea and 40.68 ％ for dark green tea.There were positive correlations between the antimicrobial activities and concentrations of polyphenols in extract solutions.Conclusion All of six types of tea show antibacterial activities which can be relevant with the degree of fermentation of tea.