In-vitro examination and isolation of antidiarrheal compounds using five bacterial strains from invasive species Bidens bipinnata L.

Bidens bipinnata is widely utilized medicinal plant for treatment of diseases like malaria, sore throat, acute nephritis and dysentery. However, despite its traditional uses Bidens bipinnata is not widely explored for its antimicrobial effect. Thus, the current study is aimed to form antimicrobial activity report of Bidens bipinnata extracts, along with isolation and evaluation of antibacterial activity of the isolated compounds through bioassay-guided purification. Hexane extract of its leaves has appeared to be most active thus it is exposed to automated column chromatography. Further purification using High-performance liquid chromatography has led to isolation of active peaks, identified by Gas Chromatography-mass spectrometry, as 16-Pregnenolone and 9-Octadecenoic acid (Z)-, methyl ester. Their antimicrobial activity was confirmed via broth dilution procedure on Staphylococcus aureus, 16-Pregnenolone revealed a strong antimicrobial activity with MIC₅₀ of 72 μg/mL whereas 9-Octadecenoic acid (Z)-, methyl ester display an MIC₅₀ of >250 μg/mL. Present study is the first report on isolation of these compounds from Bidens bipinnata.