Abstract

ANALYSIS OF ANTIBACTERIAL ACTIVITY AND WATER CLARIFICATION USING SELECTED SEED EXTRACTS

J. Renuka* and J. Karunyal

Abstract

Drinking water is currently a scarce world resource, the processing of which requires complex treatment that include clarification of suspended particles and disinfection. Plant extracts have been proposed as an environment friendly alternative due to their traditional use for the clarification and purification of drinking water. In the present investigation, various locally available seeds were screened for the clarification of water and its antibacterial activity at different pH range from 1, 5, 8 & 12 and at various temperatures 40C, 370C, 500C, 1000C, 1210C in order to find the stability of seed extracts. The study included 12 plant species, of that 7 of them exhibited antibacterial activity namely Eugenia jambolana, Moringa loeifera, Murraya koenjii, Peltophorum ferrugineum, Phyllanthus emblica, Terminalia chebula and Vitis vinifera. Moringa oleifera showed highest antibacterial activity than other seed extracts. The pH of seed extract of Moringa oleifera was found to be neutral showed antibacterial activity at altered pH by 12. Extracts of Eugenia jambolana, Phyllanthus emblica, Peltophorum ferrugineum exhibited antibacterial activity only at their natural pH. Seed extract of Moringa oleifera is thermoresistant and remained active after 5 hours treatment at 95.C.whereas other seeds doesn’t exhibited antibacterial activity at altered temperatures. Drastic decrease in turbidity was observed for Moringa oleifera within a day, seeds of Peltophorum ferrugineum and Phyllanthus emblica took a week for clarification. Microbial quality of water after clarification was analysed, seed powder of Moringa oleifera showed lesser number of bacteria (120 colonies) compared to that control (300 colonies). Coagulation was observed in the seed extracts of Moringa oleifera and Peltophorum ferrugineum subjected to 1210C due to presence of coagulant proteins. Seeds of Moringa oleifera, Peltophorum ferrugineum and phyllanthus emblica as a potential water clarifying agent which could replace the harmful chemical coagulants.

Keywords: Moringa oleifera, Peltophorum ferrugineum, Antibacterial activity, Coagulation.