EFFECT OF DIFFERENT SOLVENT EXTRACTS ON THE YIELD AND IN VITRO ANTIBACTERIAL ACTIVITY, WITH GC-MS ANALYSIS OF ACTIVE EXTRACTS FROM VERNONIA AMYGDALINA LEAVES

Abstract

Vernonia amygdalina, commonly known as ‘Bitter leaf’, is a small perennial shrub with various medicinal properties including the treatment of stomach disorders, fever symptoms, diabetes, hypertension, and coughs. V. amygdalina is a potent source of antibacterial properties that may be beneficial in preventing bacterial infections and associated diseases such as fever and diarrhea. V. amygdalina also has been extensively studied for its antioxidant, anti-inflammatory, antifungal, anticancer and antidiabetic properties. The present study aims to determine the most efficient solvent for extracting antibacterial-rich V. amygdalina extracts. Dried leaves of V. amygdalina were extracted using several solvents (methanol, ethanol, and dichloromethane) to assess the extraction yield. The antibacterial potential of all extracts against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa was evaluated using the agar disc diffusion assay. The profiling of the active extract was accomplished using gas chromatography coupled with mass spectrometry (GC-MS). Among the solvents tested, ethanol exhibited the highest extraction productivity, with a percentage yield of 49.20%. The dichloromethane extract displayed the highest inhibition zones against all bacteria strains ranging from 16.67 ± 1.20 mm to 21.33 ± 0.5 mm at 200 mg/mL. The GC-MS analysis of dichloromethane extract identified compounds such as phytol, flavonoids, vitamin E, and squalene. The findings of this study revealed that the choice of the extraction solvent is greatly affecting the antibacterial efficacy of V. amygdalina. In conclusion, the efficacy of V. amygdalina against pathogenic bacteria strains could be explored for further pharmaceutical application and should be encouraged in the development and production of new antibiotics.