Anti-microbial Activity of Aqueous Extract of Natural Preservatives - Cumin, Cinnamon, Coriander and Mint

This study was aimed to overcome the problems of artificial preservatives used in food preservation with natural preservatives. In this aspect, four different plants was selected such as black cumin, cinnamon, coriander and mint for anti-microbial activity against some food borne pathogens such as three gram negative microorganisms E. coli, P. aeruginosa, S. marcescens and three gram positive microorganisms such as Bacillus subtilis, S. aureus and B. cereus. A selected plant material was extracted by the soxhlet apparatus with water. Aqueous extract and in combination of extracts (1:1) ratio was prepared and antimicrobial activity was analyzed by agar disc diffusion method. According to the: results obtained individual extract of mint against E. coli has produced the highest zone of inhibition 18 mm. The extract of mint with coriander showed 19 mm of zone of inhibition against E. coli. Overall all the plant extract and their combination showed very good antibacterial activity. The Plant extract are most probably used for food preservation than the chemical preservatives because the chemical preservative which leaves the chemical residue on the food which can cause harm to the life. Further studies may be carried out to screen the valuable antimicrobial constituents present in the plant materials.