Effect of extraction procedure on yield, phytochemical profile and antibacterial activity of fenugreek seed (Trigonella foenum-graecum) crude extracts

Abstract

Background: Fenugreek (Trigonella foenum-graecum) is a medicinal plant known for its various pharmacological properties, including its antibacterial activity. The purpose of this study was to assess the extraction procedure effect on yield, phytochemical profile and antibacterial activity of fenugreek seed crude extracts. Methods: The extraction procedure of components from fenugreek seed possessing an antibacterial potential was first optimized. Extracts at the highest yield were analyzed for phytocomponents and their bacterial growth inhibitory effect was assessed by determining the diameter of the inhibition zone (IZ) and the minimum inhibition concentration (MIC). Result: Optimum conditions for highest yield of extract (270,78 mg/g) are as follows: solvent (water), substrate-solvent ratio (1:10), and extraction time (72 hours). Phytochemical screening revealed the presence of the major compounds known to have an antibacterial activity such as tannins and flavonoids in the aqueous and methanol extracts. The methanol extract was associated with an IZ diameter ranging from 8.46±2.25 mm up to 27.65±1.32 mm and displayed the lowest MIC (1.25 mg/ml). Our findings indicate that fenugreek seed extracted with methanol showed the best antibacterial effect against the targeted bacterial strain.