Kajian Aktivitas Antibakteri Daun Gatel (Laportea decumana (Roxb.) Wedd.) dan Daun Benalu Cengkeh
Abstract
Many researches showed that several plants have a good antibacterial activity. The leaves of gatel and clove mistletoe are empirically used to cure several diseases. The aims of this research were: (1) to study the potential of antibacterial activity of gatel and clove mistletoe hexane, ethyl acetate and methanol extracts against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium and Pseudomonas aeruginosa by the well diffusion method; (2) to calculate the minimum inhibitory concentration (MIC) value of the potential extracts; and (3) to study the effect of various pH to antibacterial activity of the extracts. The results showed ethyl acetate and methanol extracts of the studied plants have low antibacterial activity against B. cereus and E. coli. Based on the MIC values, the ethyl acetate extract of gatel leaves showed over 99% percent inhibition against E. coli at a concentration of 3.5%, 4.0%, 4.5% and 5.0%. The same result was obtained by modifying the pH (4, 5 and 6) at the extracts concentration of 5% and 10%. The methanol extract of gatel leaves showed below 60% inhibition of B. cereus at a concentration of extract 4.0%, 4.5%, 5.0%, 5.5% and 6.0%, and more than 90% inhibition at the pH. The ethyl acetate extract of clove mistletoe showed more than 98% inhibition againts E. coli at a concentration of 3.5%, 4.0%, 4.5% and 5.0% and at pH 4, 5 and 6. Percent of inhibition less than 50% occured in the methanol extract of clove mistletoe at 4.0%, 4.5%, 5.0%, 5.5% and 6.0% concentration against B. cereus. For the methanol extract of clove mistletoe, the effect of pH variation (4, 5, 6 and 7) resulted in 92%-97% inhibition. The result may increase the utilization of research plant not only for health purposes but also as a natural food preservative and open new possibilities for the development of natural functional foods.