Screening of Anti-Streptococcus pneumoniae Active Ingredients from Pilea peltata
10.3870/j.issn.1004-0781.2025.05.001
- VernacularTitle:盾叶冷水花抗肺炎链球菌活性成分筛选
- Author:
Zhiying WEI
1
;
Yan HUANG
;
Shenggao YIN
;
Jie LIANG
;
Chengsheng LU
;
Fangchan LI
;
Yuting XIE
;
Yaohua LI
;
Xiaojiao PAN
Author Information
1. 广西中医药大学附属瑞康医院教学部,南宁 530011;广西中医药大学教学实验实训中心,南宁 530200
- Publication Type:Journal Article
- Keywords:
Pilea peltate;
Anti-Streptococcus pneumoniae;
Screening of active ingredients;
Synergistic antibacterial effect
- From:
Herald of Medicine
2025;44(5):687-694
- CountryChina
- Language:Chinese
-
Abstract:
Objective To screen the anti-Streptococcus pneumoniae(Spn)active ingredients in vitro from different po-lar parts of Pilea peltata,and to examine the combined antibacterial effect of the active ingredient and amoxicillin(AMX).Methods A 96-well plate microdilution method was used to determine the minimum inhibitory concentration(MIC)of different polar parts;the most active polar part was separated by preparative high-performance liquid chromatography,and the active ingre-dients were identified using spectral technology.The fractional inhibitory concentration(FIC)of active ingredients and AMX was determined by the 96-well plate chessboard microdilution method.The crystal violet method was used to investigate the effect of ac-tive ingredients on Spn biofilm.The effect of active ingredients on the appearance and morphology of Spn was investigated under the electron microscope.Results The MICs of the petroleum ether part,chloroform part,ethyl acetate part,n-butanol part,and water part were 1.000,1.000,0.500,1.000,and 2.000 mg·mL-1 respectively,among which the ethyl acetate part had the stron-gest antibacterial activity.Three compounds were isolated from ethyl acetate,namely 5,7,3',4'-tetramethoxyflavone 1,8-O-(p-coumaroyl)-1(10)E,4(5)E-humuladien-8-ol 2 and 1-O-p-coumaroyl copaborneol 3.These compounds were all isolated for the first time from Pilea peltate,their MICs against Spn were 200.000,50.000,and 25.000 μg·mL-1 respectively,and the compound 3 had the strongest antibacterial activity;the FIC value of AMX and compound 3 was 0.50,which had a synergistic antibacterial effect on Spn.Both AMX and compound 3 had inhibitory effects on Spn biofilm,but the biofilm inhibition rate of compound 3(59.10±1.04%)was significantly lower than AMX(87.38±0.84)%(P<0.01);Moreover,there was no significant difference in biofilm inhibition rate between the combination of the two and AMX(P>0.05).The scanning electron microscope results showed that the bacterial cells in the compound 3 group had a smooth surface but varying degrees of depression.The surface of the bacteri-al cells in the AMX group and the AMX combined compound 3 group showed severe swelling and rupture.Conclusions Fla-vonoids and sesquiterpenoids are both the anti-Spn active components of Pilea peltate.Among them,sesquiterpenoids have more potent antibacterial activity,and their antibacterial action mechanism is related to inhibiting bacterial biofilms.Compound 3 and AMX have a synergistic antibacterial effect on Spn,but its mechanism of action is not by enhancing biofilm inhibition;although compound 3 cannot destroy the cell wall of Spn,it still has a negative impact on the appearance of the bacteria.