EXTRACTION, PURIFICATION AND HPLC IDENTIFICATION OF VARIOUS ENVIRONMENTALLY-SAFE PHYTOTOXIC AGENTS FROM 4 O'CLOCK LEAVES FOR PHYTOTOXIC POTENTIAL

摘要

This study was conducted to identify various environmentally safe phytotoxic agents from 4 o'clock (Mirabilis jalapa) leaves aqueous extract of ethyl acetate fraction as well as freeze dried fraction using HPLC. The different concentrations of leaves aqueous extract were attempted for the phytotoxic potential of these environmentally safe agents against common cress (Lepidium sativum). The aqueous extract retarded all the tested parameters at > 5% and 50 ppm, concentrations respectively. The colorimetric analysis showed that total phenolic contents were 69.52 mg CAE/g dry weight of 4 o'clock leaves while the HPLC analysis explained the presence of twelve lower molecular weight phenolic compounds such as salicylic, 4-hydroxycinnamic, 4-hydroxybenzoic, protocatechuic, ellagic, caffeic, m-coumaric, ferulic, vanillic, chlorogenic, syringic and gallic acid that might act as phototoxic agents. This study may be helpful to search for the environment safe natural weedicide/herbicide and get rid of the health hazard synthetic chemicals that are being used to kill the weeds for better crop production.