白刺果实提取物的体外抑菌活性研究

探讨白刺果实提取物的体外抑菌活性,以期为白刺果实的综合利用及天然食品防腐剂的开发提供依据。用石油醚、氯仿、乙酸乙酯和正丁醇分别对白刺果实95%乙醇提取物进行萃取,纸片法测定各萃取部分对大肠杆菌、枯草芽孢杆菌、金黄色葡萄球菌、酵母菌、青霉、根霉和黑曲霉7种常见的食源性污染菌的抑菌效果,并通过倍比稀释法测定乙酸乙酯部分对其中3种细菌的最低抑菌浓度。结果表明:白刺果实乙酸乙酯部分、乙醇部分和氯仿部分对3种供试细菌均有抑菌作用,其中乙酸乙酯部分抑菌效果最好,且乙酸乙酯部分对3种细菌的抑制强弱顺序为:枯草芽孢杆菌>大肠杆菌>金黄色葡萄球菌;其中乙酸乙酯部分对枯草芽孢杆菌和金黄色葡萄球菌的最低抑菌浓度(MIC)均为25mg/mL,对大肠杆菌的MIC是50mg/mL。各萃取部分对供试真菌均无明显抑制作用。 

In vitro antimicrobial activity of extracts from fruits of Nitraria sibirica pall

Evaluated the in vitro antimicrobial activity of Nitraria sibirica Pall.Fruits extracts to provide the basis for utilizating Nitraria resources and developing natural food antiseptic.Nitraria sibirica Pall.fruits were extracted with 95% ethanol,then fractionated with petroleum ether,chloroform,ethyl acetate and n-butanol respectively.The filter paper disc diffusion method was performed to determine the influence of the different extracts on the growths of 3 bacterium(Escherichia coli,Bacillus subtilis,Staphyloccocus aureus) and 4 fungus(Penicillium sp.,Rhizopus sp.,Aspergillus niger,Saccharomyces cerevisiae),and the minimal inhibitory concentrations(MICs) of ethyl acetate extracts againts the 3 kinds of bacterium were tested using the doubling dilution method.The results showed that the ethyl acetate,ethanol and chloroform extracts had antibacterial activity against the 3 kinds of bacterium.In addition,the ethyl acetate extracts presented higher antibacterial activity than others.The MIC of ethyl acetate extract against Escherichia coli,Bacillus subtilis,Staphyloccocus aureus were 25,25,50mg/mL.None of the extracts exhibited inhibitory activity against Fungus.