不同提取方法对小黄姜提取物抗氧化和抑菌活性的影响

Impact of Different Extraction Methods on the Antioxidant and Antibacterial Activities of Ginger Extract

生姜是一种典型的药食两用植物,因其富含生物活性物质而具有良好的抗氧化和抑菌作用。首先对贵州小黄姜采用2种提取工艺分别得到乙醇提取物(Ethanol extract,EE)和超声波辅助石油醚提取物(Ultrasonic assisted petroleum ether extract,UPE);其次对EE和UPE总酚、总黄酮含量和抗氧化活性进行了测定,同时还研究了EE和UPE在不同p H值条件下对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌的抑菌效果。结果表明,EE和UPE总酚含量分别为1.65 mg/mL和1.13 mg/mL,总黄酮含量分别为6.53 mg/mL和3.23 mg/mL。EE和UPE对DPPH和ABTS自由基的清除能力与浓度呈正相关,且EE对2种自由基的清除能力强于UPE。当EE浓度为6 mg/mL时,对DPPH和ABTS自由基的清除率分别达到92.32%和98.32%;UPE浓度为12 mg/mL,对DPPH和ABTS自由基的清除率分别达到91.71%和98.21%。抑菌实验结果显示EE对大肠杆菌和金黄色葡萄球菌抑菌效果更好,而UPE对枯草芽孢杆菌抑菌效果更显著。pH值对生姜提取物的抑菌活性有显著影响,p H值为中性偏碱性时生姜提取物的抑菌效果最好。

Ginger(Zingiber offcinale Roscoe)is a typical medicinal and food plant,which has good antioxidant and antimicrobial activities because of its rich bioactive substances.In this experiment,two ginger extracts of Guizhou turmeric were obtained by ethanol extract(EE)and ultrasonic assisted petroleum ether extract(UPE).The total phenol,the total flavonoid and antioxidant activity of EE and UPE were determined.And the antimicrobial activity of EE and UPE on Escherichia coli,Staphylococcus aureus and Bacillus subtilis were also studied under different pH conditions.The results showd that the total phenol content of EE and UPE were 1.65 mg/mL and 1.13 mg/mL,respectively,and the total flavonoid content are 6.53 mg/mL and 3.23 mg/mL,respectively.The DPPH and ABTS free radical scavenging ability of EE and UPE show concentration-dependent,and the scavenging ability of EE is stronger than that of UPE.When the EE concentration is 6 mg/mL,the DPPH and ABTS free radical scavenging rate are 92.32%and 98.32%,respectively.When the UPE concentration is 12 mg/mL,the DPPH and ABTS free radical scavenging rate are 91.71%and 98.21%,respectively.The results of bacteriostatic test show that EE has better antimicrobial activity on Escherichia coli and Staphylococcus aureus,while UPE has significant influence on the activity of Bacillus subtilis.The pH value has a significant impact on the antimicrobial activity of ginger extract,and the antimicrobial activity of ginger extract is the best when pH is neutral to alkaline.