ANTIMICROBIAL ACTIVITIES OF INDIGENOUS BLACK SOAP FORTIFIED WITH ALOE VERA ON SOME SELECTED SKIN PATHOGENS

Abstract

The antimicrobial activity of local traditional black soap widely used by different tribes in Nigeria against skin infections was examined against some clinical and typed isolates of pathogenic microorganisms (Staphylococcus aureus ATCC-25923, Escherichiacoli ATCC -25922,Pseudomonasaeruginosa ATCC -27853, Klebsiellapneumoniae ATCC -11930 Trichophyton rubrum and Candidaalbicans) using agar dilution method. .Black soap was prepared using ashes from dried cocoa pod husks and wood by saponification (hot method) and then fortified with Aloevera before allowing it to cure in a mould for two weeks. Black soaps was gotten from Ile-Ife (market sample).Commercial antiseptic soaps and creams: Safeguard Dettol, Delta, Robert and Tetmosol, Funbact A, Acne way and Sivoderm and Broad spectrum were also gotten. .Bacteria isolates from black soap sources are Bacillus subtilis, Bacilluscereus and Acinetobacter. Fungi isolates: Aspergillusflavus, Aspergillus niger and Neurosporacrassia were isolated from the black soap market sample and black soap with Aloe vera. Physicochemical properties of the black soaps showed they are suitable for bathing as evident in their total fatty matter of 22.390.56 for black soap fortified with Aloevera. Black soap had more inhibitory effects on almost all the pathogens used in this investigation. The highest zone of inhibition which is 5.25mm was seen with Staphylococcusaureus by the black soap with Aloe vera; while the lowest inhibitory action 2.00mm was seen with Escherichiacoli by the black soap bought from the market. Selected commercial antiseptic soaps and creams had inhibition zones ranging from 2 to14mm and 2 to 11mm respectively. The minimum inhibitory concentration, minimum bactericidal concentration and minimum fungicidal concentration of the black soap ranged from 62.5mg/ml and 500mg/ml. The mechanism of action showed that sodium and potassium ions were leaked by the black soaps from the cell of the organisms. Sodium ion was leaked to a value of 96.40ppm for Staphylococcusaureus while potassium ion leaked out to a value of 22.20ppm for Escherichiacoli. All the test organisms except Escherichacoli and Klebsiella pneumoniae were not sensitive to Amoxil, Cotrimosazole, Augmentin, Nalidixic andTetracycline. Plasmid profiling of the bacteria showed the presence of plasmids with an estimated molecular weight of 21867bp. Qualitative and quantitative screening for phytochemicals showed that Saponin had the highest values of 18.50- 30.36mg/g while Tanin had the lowest values of 1.05- 2.05mg/g across the black soap samples. The Gas Chromatography/Mass Spectrometry (GC/MS) of the black soap had showed the presence of fatty acids as the dominant functional group. The antibacterial activities exhibited by local black soap in this study could be attributed to the presence of its constituents which signifies the potential of the soap as a topical therapeutic agent. These findings therefore, justify the traditional medicinal use of theblack soap.