锦绣杜鹃花抗菌、抗炎活性及其有效部位研究

Study on Antibacterial and Anti-inflammatory Activity of Rhododendron Pulchrumand Its Active Fraction

为了研究锦绣杜鹃花的抗菌及抗炎活性,并比较不同提取方法对其抗菌活性物质的提取效率.本实验采用了甲醇冷浸法、乙醇回流法和微波萃取法分别对锦绣杜鹃花的有效成分进行提取,并采用微孔板稀释法测试提取物对多种阳性菌、阴性菌和耐药菌的抑制活性.基于其较好的体外抗菌活性,还采用RAW264.7细胞炎症模型评价了粗提物对炎症因子TNF-α的影响,并测定了各萃取物的总黄酮含量.此外,为了获取锦绣杜鹃花抗菌作用的有效部位,本实验将提取物分别用石油醚、乙酸乙酯和水萃取得到不同极性的萃取物组分,比较其抑菌活性.甲醇冷浸法获得的粗提物的抗菌活性最佳;各萃取组分中,乙酸乙酯萃取组分的抗菌效果最好,其对金黄色葡萄球菌26003的MIC值达到0.512mg/mL;提取物能明显抑制LPS诱导的炎症因子TNF-α的增加.本研究证实了锦绣杜鹃花具有较好的的抗菌抗炎活性,其抗菌作用的有效部位为乙酸乙酯萃取部位,为锦绣杜鹃花在抗菌、抗炎药物和产品研究开发方面提供了实验依据.

In this study,the antibacterial activity of the extract of Rhododendron pulchrum flower and its different extraction methods for antibacterial active substances were investigated.Extraction methods including methanol soaking,ethanol refluxing and microwave extracting were carried out.The antibacterial activities of the extracted components were evaluated by microporous plate dilution test using various positive bacteria,negative bacteria and antibiotic resistant bacteria as the tested bacteria.Based on its potent antibacterial activity,the effect of the extract on the inflammatory factor TNF-αin the RAW264.7 macrophage was also investigated.Additionally,the extractions with petroleum ether and ethyl acetate fromthe water suspension of crude extract were also carried out to got three different polar components,which were also subjected to the antibacterial test to obtained the effective part of the antibacterial activity of Rhododendron pulchrum flower.The results indicated thatthe methanol soaking was superior to the other extract methods in the aspect of antibacterial activity.Furthermore,the ethyl acetate phase,holding the greatest antibacterial effects,was the optimal active fractionof Rhododendron pulchrum flower.It displayed outstanding antibacterial activity againstStaphylococcus aureus1.2155 with MIC value of 0.512 mg/mL.The extract could significantly inhibit the increase of the TNF-αinduced by LPS.It can be concluded thatRhododendron pulchrum flower exhibited antibacterial and anti-inflammatory activities,and the ethyl acetate extracting after a methanol soaking of the medicinal plant was a proper method to obtain its antibacterial active ingredients.