Pods of Khejri (Prosopis cineraria) consumed as a vegetable showed functional food properties

The arid plant Prosopis cineraria (Fabaceae) is known as Khejri in India or the golden tree of Indian deserts. The dried pods are consumed as a vegetable and leaves as traditional medicine to cure a wide range of diseases in the state of Rajasthan, India. The pods of this plant have not been investigated for their bioactive components, hence we have done so in this study. The dried pods were boiled with water to afford the aqueous extract. Extraction of the residue gave methanolic extract. The lipid peroxidation (LPO) and cyclooxygenase enzymes (COX-1 and -2) inhibitory activities of extracts and major compounds present in the bioactive extracts were then determined. Purification of bioactive extracts yielded compounds 1-7. The absorbance of 1-7 at 570 nm ranged between 0.15 and 0.45 at 50 mu g/mL whereas vitamin C and tert-butylhydroquinone (TBHQ) at 25 mu g/mL gave an absorbance of 0.5 in the MTT [3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide] assay. At 25 mu g/mL concentration, compounds 1-7 inhibited LPO, COX-1 and -2 enzymes between the ranges of 15-87%, 21-67% and 16-59%, respectively. This is the first report of the chemical and biological activities of the edible part of this plant. (C) 2011 Elsevier Ltd. All rights reserved.