Sunday O Okoh
University of Fort Hare, South Africa
Title: Bactericidal, antioxidant, and cytotoxicity properties of hexane, methanol and volatile oil leaf extracts of Crassula multicava, grown in South Africa
Biography
Biography: Sunday O Okoh
Abstract
Oxidative stress-related and infectious diseases (OSD and IDs) especially those due to multi-drug resistant bacterial strains (MRBS) are almost incurable globally. Apart from the challenges posed by MRBS to synthetic drugs, antibiotics exhibit side effects. There is dearth of information of chemical composition of most plants such as Crassula multicava leaf claimed effective by traditional health practitioners in management of OSD & IDs including diabetes, cancers, tuberculosis, and HIV in Africa.We aimed to investigate the bioactive metabolites of C. multicava from n-hexane, methanol and volatile oil extracts (NHE, MNE & VOE). The hydrodistilled VOE was characterized by GC-MS and Kovat’s index; antibacterial, antioxidant and cytotoxic extracts effects were examined by micro-dilution, spectrophotometric and haemolytic techniques respectively. The VOE was bactericidal against three out of the five reference bacterial strains (BS) and one confirmed MRBS at < 0.030mg/mL including Staphylococcus aureus NCIB 50080, Listeria ivanovii ATCC19119. The NHE minimum bactericidal concentration was > 0.35mg/mL against test BS, except for L. ivanovii at 0.25mg/mL, while MNE was bacteriostatic at 0.40 mg/mL on test BS linked to IDs. The IC50 of 0.12mg/mL for VOE was the best, compared to NHE and MNE (0.40 and 0.96mg/mL respectively) in reducing lipid radical associated with OSD. Behenyl alcohol (20.25%), linoleic acid (10.83%) and 2,3,4,6-tetramethyl phenol (8.74%) were the major secondary metaboliteis. None of the extracts was toxic at < 0.75mg/mL. The study indicates that the VO of C. multicava contained potent metabolites, noteworthy bioactivities, useful as natural medicine, food preservative and antimicrobial agent.