Anti-urease and antioxidant activities of the leaf extracts from Murraya paniculata (L.) Jack (Rutaceae)

This report is on the urease inhibitory and free radical scavenging activities of the leaf extracts of Murraya paniculata.  The pulverized plant sample (314 g) was extracted by successive cold maceration using n-hexane (non-polar), acetone (moderately polar) and absolute ethanol (polar) for 72 hrs. Phytochemical screening done using standard phytochemical methods, urease inhibition using modifed Berthelot method and free radical scavenging using 2, 2-diphenyl-1-picryl hydrazyl (DPPH) spectrophotometric assays. The bioactive extract was fractionated on chromatography column packed with normal phase silica gel (200-400 mesh size) and eluted using gradient mixtures of n-hexane, dichloromethane and methanol. The pooled fractions from the column were assessed for bioactivity. The functional group investigation was done using infra-red (IR) spectroscopy. Alkaloids, flavonoids, triterpenoids, phenols, steroids, and carbohydrates were present in the extract.  The acetone extract displayed the highest free radical scavenging activity (54.186±0.0004) with IC 50 value: 0.84 mg/ml, and urease inhibition. Its dichloromethane-methanol column chromatography fraction had the highest free radical scavenging activity at 0.8 mg/ml (60.65±0.062) with an IC50 value: 0.49mg/ml. The activities were quite significant compared to the standard (Ascorbic acid) at P<0.05. The bioactive dichloromethane-methanol column chromatography fraction evidenced vibration stretching bands [3440 cm-1 (O-H), 2975 cm-1 (C-H), 1745 cm-1 (C=O), 1634 cm-1 (C=C), 1290 cm-1(C-N), and 1134/1007 cm-1 (C-O)] from the IR spectroscopy thus corroborating the detected phytochemicals. These current results validate the use of the M. paniculata in managing oxidative stress and other reported traditional uses in addition to the potentials for its use in the discovery and development of eco-friendly urease inhibitors for sustainable agriculture.