紫苏甲醇提取物的体外抗氧化及抑菌活性研究

Study on in vitro antioxidant and antimicrobial activities of methanol extract from Perilla frutescens L.

研究了紫苏不同部位(苏叶、苏梗、苏子)中的多酚、黄酮含量,并考察了紫苏甲醇提取物的抗氧化及抑菌活性。结果表明,苏叶中的多酚、黄酮含量均为最高,分别为1.34、0.72mg/g,其次为苏子、苏梗;苏叶甲醇提取物清除DPPH能力及铁还原能力最强;苏梗甲醇提取物对ABTS自由基具有较好的清除效果。抑菌试验结果表明,苏叶提取物的抑菌效果最好,对敏感菌株大肠杆菌的MIC、MBC值分别为40、80μg/mL。紫苏叶是一种较好的天然抗氧化剂和防腐剂资源。

The content of total polyphenols and flavonoids, as well as the antioxidant and antimicrobial activities of methanol extract from different parts （leaf, stem, and seed） of Perilla frutescens in vitro were studied in this paper. The results showed that, total polyphenols, flavonoids in Perilla leaf were the highest, with the content of 1. 34 and 0. 72 mg/g respectively, followed by Perilla stem and seed. The ethanol extract from Perilla leaf exhibited the better scavenging activity on DPPH radicals and ferric reducing antioxidant power （FRAP）, while the ethanol extract from Perilla stem showed the better scavenging activity on ABTS radicals. The results of test on antibacterial activity showed that the methanol extract from Perilla leaf presented the better antibacterial activities against some food borne pathogens, especially it presented the best inhibitory effect against Escherichia coli, with a minimum inhibitory concentration （MIC） and the minimum bactericidal concentration （MBC） of 40, 80 txg/L, respectively. The leaves of Perilla frutescens is one of good resources from which natural antioxidant and food antiseptic agent are produced.