Research Article of International Journal of Traditional and Complementary Medicine
Antibacterial, antifungal and wound healing potentials of extract and fractions of Nauclea diderrichii root bark
Theophine Chinwuba Akunne1*, Bonaventure C. Obi1, Paul A. Akpa2, Sunday O. Udegbunam3, Adaobi J. Anaenugwu1
1Department of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria
2Department of Pharmaceutics and Pharmaceutical Microbiology, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria
3Department of Veterinary Surgery, Faculty of Veterinary Medicine, University of Nigeria, Nsukka, Enugu State, Nigeria
This study was aimed to evaluate antimicrobial and wound healing effects of root bark extract and fractions of Nauclea diderrichii Merrill (Rubiaceae). Dried root barks of N. diderrichii was extracted using methanol and dichloromethane (1:1) to obtain methanol-dichloromethane extract (MDE). The MDE was fractionated using chromatographic techniques to obtain n-hexane (HF), ethylacetate (EF) and methanol (MF) fractions. The antimicrobial effect was tested against selected organisms using agar diffusion and agar dilution technique to determine the inhibition zone diameters (IZD) and minimum inhibitory concentrations (MICs). The excision wound model was used to assess the wound healing properties of MDE (5, 10 and 20%) and compared it with that of bacitracin and neomycin powder (BNP, standard) in rats. Phytochemical screening and acute toxicity test were performed using standard procedures. Results showed that extract and fractions exhibited antimicrobial effect with IZD (mm, 40 mg/ml) against tested organisms. The EF exhibited the best antimicrobial activity with IZD of 30, 8, 15, 8 and 12 against Staphylococcus aureus, Staphylococcus cohnii, Pseudomonas aeruginosa, Klebsiella aerogenes and Aspergillus flavus, respectively. The EF also gave an MIC (mg/ml) of 0.63, 20.00, 1.25, 20.00 and 0.63 for S. aureus, S. cohnii, P. aeruginosa, K. aerogenes, and A. flavus, respectively. The MDE showed a comparable wound healing effect with BNP, although with better effect on day 20 with 100% wound contraction while BNP gave 93.79%, post wound excision. Therefore, N. diderrichii root bark possesses antibacterial, antifungal and wound healing properties.
Keywords: Nauclea diderrichii, antibacterial and antifungal activity, phytochemical screening, wound healing.