نوع مقاله : مقاله پژوهشی
1 دانش آموخته دکتری گروه شیلات، دانشکده منابع طبیعی، دانشگاه تهران، کرج ، ایران.
2 استاد گروه شیلات، دانشکده منابع طبیعی، دانشگاه تهران، کرج ، ایران.
3 دانشگاه گرگان, گروه شیلات، دانشکده منابع طبیعی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان
4 استادیار موسسه تحقیقات علوم شیلاتی کشور، پژوهشکده آبزی پرروری آبهای داخلی، سازمان تحقیقات، آموزش وترویج کشاورزی، بندرانزلی، ایران.
عنوان مقاله [English]
Despite a good phytochemical potential, common water hyacinth (Echhornia crasipes) is considered among the worst weeds in the world due to its high reproductive capacity. Since medicinal use of the weeds is new and innovative approach for researchers, the present study was carried out to evaluate the antimicrobial effects of aquatic and hydro-methanolic extracts of common water hyacinth on pathogenic agents. The dried powder of common water hyacinth leaves was extracted with 80% methanol and water using soaking extraction. Antimicrobial activity was investigated on two aquatic and three clinical pathogenic species. The zone of inhibition was evaluated employing the agar diffusion test (well) using 5, 20, 100, and 400 mg/mL of each extract. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using the agar dilution method. The hydro-alcoholic extract had the largest zone of inhibition on the aquatic pathogenic species Streptococcus iniae. The aqueous extract had the highest antimicrobial effect on Escherichia coli (P≤0.05).Paired comparison of the independent t-test on the effect of solvent type on the studied bacterial species showed that antimicrobial activity significantly increased against E. coli in hydro-methanolic extract and against S. iniae in the aqueous extract (P>0.05).MIC and MBC were 64-256 mg/mL and 128-512 mg/mL, respectively. The extract of the weed common water hyacinth has antimicrobial effects due to the presence of the effective secondary metabolites belonging to phenolic, tannin and alkaloid groups of compounds, and the type of solvent used is effective on the degree of antimicrobial activity.