Anti-oxidants are crucial to human health. They have capacity to neutralize the free radicals responsible for giving birth to a variety of diseases. A diet rich in foods with high levels of anti-oxidants is associated with longevity and good health. We tried to replace the chemical anti-oxidants by herbal anti-oxidants. In plants, the anti-oxidants are present as flavonoids,so the flavonoids in Urena lobata were isolated , identified, quantitatively estimated and tested for their anti-oxidant activity.The flavonoids were extracted from the stem and the leaves separately to know the relative contents. Quercetin and Kaempferol were found to exist in the plant material.These were qualitatively tested by the method of Thin Layer Chromatography (TLC). The isolation, purification and quantitative content determination was performed by preparative thin layer chromatography (PTLC). The anti-oxidant activity of the methanolic plant extract was examined by DPPH radical scavenging activity method. The anti-oxidant ability of the plant extract was found comparable with Vitamin C.

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Powdered Abutilon indicum leaves were extracted from chloroform. Thin layer chromatography technique in combination with column chromatography was used to separate the chemically active constituents. The constituents were subjected to IR, NMR, EIMS analysis to identify the compounds contained in the extract. The antimicrobial activity of the plant extract was examined on Bacillus subtils, Klebsiella pneumonia, Pseudomonas aeruginosa, E.coli and the effect was compared with that of chloramphenicol. The comparative results showed that chloroform extract of Abution indicum can serve well as an antimicrobial agent.

The aqueous and alcoholic extract of Urena lobata flowers has been used in acid/alkali titrations over a wide range of concentration. The results obtained with the flower extracts have been compared with those obtained by using traditional chemical indicators like phenolphthalein and methyl orange. It has been established experimentally that the flower extract can be successfully used in place of phenolphthalein and methyl orange for acid/alkali titrations. The presence of anthocyanins is supposed to impart pH sensitive colour dependence to the natural indicator.