Antibacterial effect of combined garlic and turmeric extracts against Escherichia coli.

   Recently, people have turned to organic and natural products, such as spices, as alternatives to commercial drugs. This study aimed to determine the antibacterial effect of combined garlic and turmeric extract against Escherichia coli. The bacteria from the culture were inoculated in the Mueller-Hinton Agar in the presence of different concentrations of the combined garlic and turmeric extract. The growth was then assessed after the incubation period of 24 hours and the zone of inhibition (ZOI) was measured using a microcaliper. The extracts were obtained from garlic cloves and turmeric rhizomes, while the bacterial culture was obtained from University of San Carlos - Talamban Campus. Concentrations of 25%, 50%, 100% were used. Control groups were used for comparison. The positive control used was Ciprofloxacin antibiotic and the negative control used was 95% ethanol. The Kirby Bauer disc diffusion susceptibility test was done to observe the antibacterial effect within a sample of nine (9) replicates per treatment groups.

   After 24 hours of incubation, it was observed that only the experimental group of 100% concentration of the combined extract and the positive control (Ciprofloxacin antibiotic) exhibited a zone of inhibition, while the experimental groups of 25% and 50% concentrations, as well as the negative control (95% ethanol) did not. The mean zone of inhibition at 100% concentration was 10.78±1.20 mm. The significant mean zones of inhibition of the positive control group and other experimental groups (25% concentration and 50% concentration) of combined garlic and turmeric extract were not computed due to the uniformity or the lack of differences of the resulting zones of inhibition of the treatment groups.

   In conclusion, Escherichia coli was resistant to the combination of garlic and turmeric extract. To the general public, the researchers recommend not to use combined garlic and turmeric as a natural alternative treatment to E. coli. The researchers recommend future researchers to conduct separate studies on the antibacterial effect of pure garlic extract and pure turmeric extract against E. coli.