Abstract

Common buckwheat (Fagopyrum esculentum Moench) is a rich source of bioactive compounds such as rutin, quercetin, and polyphenolics that have been suggested to possess antimicrobial properties. This study aimed to evaluate in vitro antimicrobial activities of the methanolic extracts from leaves and sprouts of common buckwheat against clinically relevant bacterial and fungal strains, and to determine their chemical compositions using Fourier Transform Infrared Spectroscopy (FTIR). Methanolic extracts of buckwheat leaves and sprouts were studied against 10 bacterial strains (Pseudomonas mosselii, Bacillus cereus, Escherichia coli, Serratia rubidaea, Klebsiella michiganensis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogenes, and Enterococcus faecium) and two fungal strains (Candida albicans and Candida krusei) using the agar well diffusion method. The highest zone of bacterial inhibition was observed with leaf extract (21.9 ± 0.4 mm, p = 0.000000437) against S. rubidaea, while the lowest suppression was shown against B. cereus with values of (16.3 ± 1.2 mm, p = 0.0000126), and there is no observable activity shown against C. albicans (p = 0.00). The sprout extract showed the highest activity against S. pyogenes (17.3 ± 0.7 mm, p = 0.0000371) and the lowest against C. krusei (15.7 ± 0.62 mm, p = 0.0000437). FTIR analysis shows the presence of alcohols, esters, ketones, nitro compounds, and carboxylic acids in leaf and sprout extracts of buckwheat. These functional groups are a part or function as bioactive compounds, including antimicrobials. These findings suggest that common buckwheat is a potential source of natural antimicrobial agents, which should be further investigated to identify the phytochemicals by GC-MS, LC-MS, synergistic effects, and toxicities before therapeutic applications.

Key words: Antimicrobial activity, Buckwheat, Fagopyrum esculentum, Phytochemicals