Gerson, S.¹ Green, L.H.² ¹The Foundation for Holistic Medical Research, Brewster, NY .²Westbury Diagnostics, Farmingdale, NY
In recent years, in an attempt to discover new antimicrobial compounds, many different sources have been explored. In this study an MIC protocol was developed and then used to test ethanol, methanol, and ethyl acetate extracts of Morinda citrifolia Linn, for antimicrobial activity against A. niger (ATCC 6275), C. albicans (ATCC 10231), E. coli (ATCC 25922), S. aureus(ATCC 25923), and T. mentagrophytes (ATCC 9533). Liquid extracts were obtained, and tested in microtiter wells in duplicate. Quantities of the extracts, ranging from 6ul to 200 ul, were placed in wells and dried. A McFarland 0.5 solution of each organism was prepared, and a 1/100 suspension into the appropriate media was made. This organism suspension was added to each well, and incubated for an appropriate amount of time at the appropriate temperature. Plates were then examined for growth, and MIC’s were determined. All duplicate results agreed within one dilution. The ethyl acetate extracts had the least amount of antimicrobial activity, only showing activity when tested against T. mentagrophytes and S. aureus. The ethanol extracts showed antimicrobial activity against all of the organisms tested. This activity ranged from off-scale on the low end when tested against T. mentagrophytes, to high on-scale results for A. niger. Methanol extracts also had activity against all of the organisms tested, and ranged from off-scale on the low end when tested against T. mentagrophytes, to high on-scale results for A. niger. These results indicate that extracts of Morinda citrifolia Linn. contain antimicrobial activity most significantly against various strains of fungi.