Evaluation of Different Fractions of Garcinia kola Extracts against Multidrug Resistant Clinical Bacterial and Fungal Isolates

Background: The effectiveness of antibiotics used in the treatment of bacterial infections has been on the decline due to bacterial resistance. To improve clinical management of recalcitrant bacterial infections, alternative therapy such as medicinal plant products are now being evaluated. This study investigates the antimicrobial effects of Garcinia kola fractions on clinical isolates of multidrug resistant gram negative bacteria and Candida. Materials and Methods: Escherichia coli , Acinetobacter baumannii, Serratia marcescens and Candida species were used for the study. Microbial isolation and antimicrobial susceptibility test was carried out using basic microbiological procedures. Confirmation of all isolates was done using the VITEK 2 compact automated system (BioMerieux, Marcy I’Etoile France). The powdered dried seeds of G. kola were extracted with 70% methanol for 7 days, using a cold maceration method. The crude extracts were evaporated to dryness, using different solvents to obtain the fractions according to standard fractionation techniques. Results: The aqueous, butanol, chloroform and hexane fractions at minimum inhibitory concentrations (MIC) of 25mg/ml were active against A. baumannii. Ethyl acetate fraction at MIC of 20 mg/ml also produced growth inhibition of same isolates. At the same MICs, the different fractions were observed to inhibit the growth of candida albicans (CF1) isolate. Overall, aqueous fraction of G. kola produced more growth inhibition followed by butanol fractions, with chloroform fractions producing the least effects. Conclusion: The antibacterial potencies of these extracts could be useful for the treatment of multi-drug-resistant A. baumannii. The aqueous fraction showed better activities than the other fractions studied.