Antimicrobial Effect of Leaves of Phyllanthus niruri and Solanum nigrum on Caries Causing Bacteria: An In vitro Study

and are which are indigeneous to India. commonly called 'manathakkali Keerai' in Tamil, forms an indispensable part of South Indian diet. (keezhanelli in Tamil) is a widely used medicinal plant, the leaves of which have been used extensively in Ayurveda and native medicine to cure various liver ailments. The herbs and have been found to be effective against numerous enteropathogens in various in vitro studies. To assess and compare the antibacterial efficacy of the crude alcoholic extract of the leaves of and against five cariogenic organisms. Standard strains of the micro-organisms were obtained from ATCC (American Type Culture Collection) and MTCC (Microbial Type Culture Collection) which comprised of MTCC no. 890, MTCC no 2696, MTCC no. 10307, ATCC no. 10556 and ATCC no. 13419. The organisms obtained were revived and lawn cultured on Trypticase Soy Agar-Blood Agar (TSA-BA) and de Man, Rogosa and Sharpe (MRS) agar media. The antibacterial effect of the dried and powdered leaves of and was tested using agar well diffusion method. The zones of inhibition obtained after incubation were measured and tabulated. The antibacterial activity for the two herbs was compared using the Mann-Whitney test. The antibacterial zones of inhibition obtained for the herb was in the range of 12.3-14.6 mm and ranged from 9.7-11.6 mm for the herb . When the zones of inhibition were compared for the herbs, showed significantly greater zones of inhibition compared to for the organisms , , and (p-value