IN VITRO ASSESSMENT OF ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF METHANOL EXTRACT FROM LEAVES OF GOSSYPIUM HIRSUTUM

ABSTRACT The leaves of Gossypium hirsutum have historically been used to treat wound and a number of bacterial illnesses. Hence, this study seeks to screen the methanol leaf extract of G. hirsutum for its chemical composition, antioxidant and antimicrobial activities in order to find possible sources of novel phytochemicals. Qualitative and quantitative phytochemical screenings were conducted on the extract using standard method. The different phyto compounds in the extract were identified using Gas Chromatography mass spectrometry (GC-MS). The antioxidant activity of the extract was evaluated using 2,2-diphenyl-1-Picrylhydrazy (DPPH), Nitric oxide scavenging (NOS) and 2,2-azino-bis-3-ethylbenzo thiozoline-6-sulphonic acid (ABTS) assays while the antimicrobial activity was estimated using the zone of inhibition method. The qualitative phytochemical screening showed that the extract has phenol, flavonoid, terpenoid, steroid, proanthocyanidin, phytate, tannin and saponin while the quantitative screening showed that the extract contains the above-named phytochemicals in different concentration and phenols been the highest 759.66 ± 16.03mg/100g of the extract. The GC-MS analysis showed the presence of fifty-one (51) compounds accounting for 99.50% of the total component of the crude extract. The major compounds found in the extract include palmitic acid 20.415, caryophyllene 13.65% and α – linolenic acid 13.49%. The methanol leaf extract showed percentage DPPH, ABTS and NOS radical scavenging activity of 44.10 ± 3.20, 64.06 ± 0.63 and 55.44 ± 0.99 respectively. The extract was active against some Bacillus species, Bacillus polymyxa (NCTC10343) 17.75 ± 0.25, Bacillus stearothermophillus (NCIB 8222) 14.75 ± 0.75 and Bacillus cerus (NCIB 532) 13.50 ± 0.5. The leaf extract exhibited promising antioxidant and antimicrobial properties, offering a potential source for the discovery and development of novel therapeutic agents.