抗幽门螺杆菌活性挥发油的筛选、药效物质分析及其作用机制预测

目的探讨抗幽门螺杆菌(HP)活性挥发油的药效物质,初步预测潜在活性成分及其作用机制。方法微量稀释法(96微孔板)测定丁香、广藿香、紫苏、牛至、枳实、厚朴、薄荷、肉桂8种挥发油对HP的抑制率,筛选出抑菌活性最强的3种挥发油。气相色谱-质谱法联用(GC-MS)分析3种挥发油的化学成分,利用TCMSP、Swiss TargetPrediction、PubChem数据库获取3种挥发油主要活性成分及其对应靶点信息;网络药理学技术预测其潜在活性成分、相关通路及关键靶点;AUTODOCKVina软件对核心成分及关键靶点基因进行分子对接,初步验证潜在活性成分及关键靶点。结果广藿香、牛至和肉桂挥发油抑制90%细菌生长的最低药物浓度(MIC_(90))分别为0.250、0.250、0.125μL·mL^(-1),具有较强的抑菌活性;从以上3种挥发油中分别鉴定出27、26、15个化学成分,共筛选出15个活性成分,涉及232个基因靶点,影响了与抑制HP相关的癌症通路、化学致癌-受体激活及EGFR酪氨酸激酶抑制剂耐药性等275条信号通路;分子对接验证结果显示3种挥发油抗HP与SRC蛋白密切相关,15个活性成分与关键靶点SRC的结合较为稳定。结论广藿香、牛至、肉桂3种活性挥发油通过多成分、多靶点、多通路的形式发挥抗HP作用。

马来鱼藤中一新的鱼藤酮类化合物及相关成分的抗幽门螺杆菌活性

作者发现鱼藤酮具很强的抗幽门螺杆菌活性(MIC 为1.3μg/mL),进而从马来鱼藤Derris malaccensis Prain 根分离出一新的鱼藤酮类化合物 derrisin(1)和10个已知的该类化合物,并研究了它们的抗幽门螺杆菌活性。该植物干燥根的甲醇提取物用乙酸乙酯和水分配提取。乙酸乙酯部位具有显著的抗幽门螺杆菌活性,IC_(50)<1μg/mL。

The Antagonistic Activity of the Lactic Acid Bacteria （Streptococcus thermophilus, Bifidobacterium bifidum and Lactobacillus bulgaricus） against Helicobacter pylori Responsible for the Gastroduodenals Diseases

The lactic acid bacteria are used in fermentation and the bio conservation of food, because it produces organic acids and other antibacterial substances as the bacteriocin to inhibit certain pathogenic stocks. In order to demonstrate the inhibitory effect of these bacteria, we studied the antagonistic capacity of the two leavens of yoghourt （Streptococcus thermophilus and Lactobacillus bulgaricus） and Bifidobacterium bifidum with respect to Helicobacterpylori by the method of diffusion by discs. Their interactions led to the emergence of large zones of inhibition. Bifidobacterium bifidum led the greatest halo with a diameter of 0.8 cm by contribution to Lactobacillus bulgaricus （0.5 cm） and Streptococcus thermophilus （0.3 cm）. The additional tests were required to know the exact nature of the inhibitors. The results showed that the antibacterial peptides （bacteriocins） have a narrow spectrum of activity against the species pathogen compared to that caused by acidity.