有梗石龙尾甲醇提取物抗志贺菌病作用的体内和体外研究(英文)

In vitro and in vivo evaluation of the inhibitory effect of Limnophila indica(Linn.) Druce on shigellosis

目的:探讨有梗石龙尾甲醇提取物抑制志贺菌病的作用。方法:首先将有梗石龙尾甲醇提取物做初步化学筛选。使用2种革兰阴性菌、2种革兰阳性菌,2种抗生素耐药的志贺杆菌和1种非抗生素耐药的志贺杆菌经纸片扩散法进行体外抗菌筛选。蓖麻油诱发 Wistar大鼠腹泻后,以洛哌丁胺作为标准对照药进行有梗石龙尾甲醇提取物止泻实验。通过人工胃模型测定有梗石龙尾甲醇提取物的体外抗酸作用,并且对其中和胃酸的效率、容量、体积和氢离子消耗进行评估。结果:有梗石龙尾甲醇提取物中含有酚类、黄酮类、生物碱等化学成分,以及脂肪和油脂。有梗石龙尾甲醇提取物被证明对包括抗生素耐药的志贺杆菌在内的4个菌株具有较强的抑制作用,并且其抗腹泻作用具有剂量依赖性。当服用最低剂量100mg/kg时,其抗腹泻效果比标准对照药洛哌丁胺更好(P<0.01)。体内实验结果显示有梗石龙尾甲醇提取物具有轻微的抗酸作用。结论:有梗石龙尾甲醇提取物具有轻微的抗酸活性以及强效的抗菌、止泻作用,这对于开发抗痢疾、抗腹泻作用的草药具有一定的意义。

OBJECTIVE： The research aimed to evaluate the anti-Shigella and antacid activities of the methanolic extract of Limnophila indica. METHODS： The whole plant of L. indica was extracted using methanol and then subjected to preliminary chemical screening. The in vitro antibacterial screening on two Gram-positive and two Gram-negative bacteria as well as three Shigella species of which two bacteria were antibiotic-resistant were evaluated by disc diffusion method. Castor oil-induced diarrhoea on Wistar albino rats was performed by using Ioperamide as a standard control. The in vitro antacid activity was tested by artificial stomach model. The neutralization efficiency, capacity, volume and hydrogen ions consumed were also evaluated. RESULTS： The preliminary chemical screening on methanolic extract of L. indica showed the presence of phenolic compounds, fiavonoids, alkaloids, fats and oils. It was proved to be a potent antibacterial agent against the four bacterial strains. Screening against Shigella species revealed that it was a powerful antibacterial agent towards antibiotic-resistant Shigella species. In the case of in vivo antidiarrheal activity, the plant has shown a dose-dependent activity and the lowest dose at 100 mg/kg gave a much better result than Ioperamide （P〈0.01）. The in vitro antacid study showed a mild activity. CONCLUSION： As the plant L. indica has been proved to be a competent antibacterial as well as a compelling antidiarrheal agent with mild antacid activity, this plant can be very well suggested to be an eminent substitute for the various synthetic anti-dysentery and antidiarrheal agents available in the market.