A Comparative Study Between the Efficacy of Calamondin Extract and Isopropyl Alcohol in Inhibiting Salmonella typhi Growth

Abstract

Typhoid fever is a disease caused by the gram-negative bacteria, Salmonella enteric serovar Typhi. It is especially widespread in underdeveloped communities. Together with bacterial diarrhoea and hepatitis A, it is among the most common food-borne and water-borne infectious diseases in the Philippines. In rural communities of the Philippines, where many Filipinos have very limited means of managing the spread of bacteria, as well as sanitising themselves, they become prone to contracting not only Typhoid fever but other diseases as well. In hopes of providing a cheaper alternative to rubbing alcohol, the antimicrobial effects of Citrus microcarpa(calamondin) extract, in different concentrations, were tested on the S. enteric serovar Typhi bacteria. The researcher hypothesised that the 70% calamondin extract would be able to exceed the efficacy of the 70% alcohol. The researcher first extracted the fruit juice, peel, and sacs. By conducting the agar diffusion test, the researcher was able to obtain the diameter of the zone of inhibition of the different concentrations of the citrus extract and 70% isopropyl alcohol. The 70% isopropyl alcohol was set as the standard, and the diameter of the extracts’ zone of inhibition was then compared to the diameter of the alcohol’s zone of inhibition. Five trials of this experiment were done to increase the validity and accuracy of the data. Although the results of the experiment showed that only the 100% calamondin extract exceeded the efficacy of the alcohol, the results evidenced the promising potential of the fruit as an antimicrobial agent. The difference between the zone of inhibition of the 70% isopropyl alcohol and the 70% calamondin extract is not too large either. The diameter of the zone of inhibition of the alcohol, 10%, 30%, 70%, and 100% calamondin extract is9.65 mm, 7.50 mm, 8.10 mm, 9.25mm, and 10.65 mm respectively.