Antioxidant, antibacterial and phytochemical properties of two medicinal plants against the wound infecting bacteria

Abstract

Objective To investigate the antioxidant, antibacterial and phytochemical properties of ethanol extracts of Brachylaena elliptica and Brachylaena ilicifolia against wound infecting bacteria normally found in diabetic patients. Methods The in vitro antioxidant activity of the two plants extracts were investigated spectrophotometrically using 1,1-diphenyl-2-picrylhydrazyl, nitric oxide, azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt, hydrogen peroxide (H 2 O 2 ) and ferric reducing power. The antibacterial assay and minimum inhibitory concentration (MIC) was determined using the agar dilution method against five bacteria strains using amoxycillin and ciprofloxacin as positive control. The phytochemical analyses (tannins, total phenol, flavonoids, flavonols, proanthocyanidin, alkaloids and saponins) were assessed using standard methods. Results The ethanol extract of both plants exhibited strong antioxidant activities in some cases when compared to the standards (vitamin C and BHT). The antibacterial activity of both plants showed an appreciable broad spectrum activity against these wound pathogens with MIC value ranges between 0.3 mg/mL and 5 mg/mL. Tannins, phenols, flavanols, proanthocyanidins and alkaloids content of B. ilicifolia were significantly higher than those in B. elliptica . However, there were no significant differences in the flavanoid content of both plants extracts. Conclusions These results indicated that the ethanol leaf extracts of these plants have antioxidant and antibacterial activity against the tested bacteria possibly due to the presence of bioactive compounds and therefore could be used as alternative therapy against wound infection caused by these bacteria in diabetic patients.