ANTIMICROBIAL ACTIVITIES OF INDIGENOUS BLACK SOAP FORTIFIED WITH Jatropha Curcas AND Acalypha wilkesiana ON SOME SELECTED SKIN PATHOGENS

Abstract

Antimicrobial activity of black soap fortified with Jathropha curcas and Acalypha wilkesianawas carried out against skin pathogenic organisms using disc diffusion method. The test was conducted on six organisms viz Staphlococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, Trichophyton rubrum, and Klebisiella pneumoniae while the Typed organisms were Staphylococcus aureus ATCC-25923, Pseudomonas aeruginosa ATCC-27853 Escherichia coli ATCC-25922, Klebsiella pneumoniae ATCC-11930, and Candidaalbicans ATCC-10261.The samples of soap used were: soap fortified with Jathrophacurcas, Acalypha wilkesiana, varying concentrations of both combined, conventional black market soap and septol. The highest zone of inhibition was obtained when the black soap was fortified with Acalypha wilkesiana (28 ± 0.00mm) and lowest (8.00±0.00) for Escherichia coli and Candida albicans respectively. Standard antibiotics were used as positive control. All the bacterial isolates were sensitive to Cotrimoxazole, Amoxacilin, Tetracycline, Nalidixic acid, Gentamicin Ofloxacin and Nitrofurantroin except Augumentin. Also all the test organisms except Candidaalbicans were sensitive to the five conventional antimicrobial body creams and ointments (Tydineal, Funbat A, mycoten, Romicin and mercy ointment). The antagonistic effect of bacterial isolates from the soap revealed that Bacillus spp inhibits all but one E.coli. Thepercentage (%)moisturecontents of black soap fortified with Jathropha, Acalypha and their combination were 53.50 ± 0.17, 45.0 ± 1.41 and 66.0 ± 1.41 respectively. The moisture content of black soap prepared in the laboratory (9.50 ± 0.71) was lowest when compared with those purchased in the open market (10.50 ±0.71 – 17.00 ±0.00). Both fortified and non fortified black soaps have varying degrees of solubility in Ethanol (g) (0.53±0.42- 1.47 ±0.02) and water (0.62±0.21-2.35 ±0.00). Total fatty acid of all the soap were low (0.03- 0.62) and were alkali(pH8-9) in nature except soap fortified with Acalypha and market sample that were slightly acidic (pH 6 and 5).The minimum inhibitory concentrationsmg/mL(31.25) and minimum bactericidal concentrations(62.5) of the soaps were determined. The mechanism of action showed that sodium and potassium ions were leaked by the black soaps from the cell of the organisms. Sodium ion and Potassium ion that was leakedby the soap was high in bacterial while the value was lower in fungi.Qualitative and quantitative screening for anti-nutrient compounds indicated presence of Alkaloids with the highest values across the black soap samples. Structural elucidation of methylatedfraction of the black soap by Gas Chromatography/Mass Spectrometry (GCMS) has shown the presence of fatty acids (dodecanoic acid) as the dominant functional groups.This study has shown that the antimicrobial activities of the black soap may be attributed to the presence of anti-nutrient compounds, stearic acid (fatty acid) and its bacterial flora.