Proximate composition and biological activity of Chilean Prosopis species

Abstract

The proximate and amino acid compositions of the leaves and pods of Prosopis chilensis and P tamarugo and the leaves of P alba have been assessed. The biological activity of the leaves and pods of the first two species as well as the leaves and exudate of P alba has been determined for free radical scavenging activity, xanthine oxidase inhibition and DNA binding. The best protein source among the forage trees was the leaves of P chilensis; P alba and P tamarugo leaves showed higher crude protein, fat and nitrogen-free extract values than reported in previous studies. According to their amino acid profiles, all species surveyed are deficient in essential amino acids. The alkaloids beta-phenethylamine and tryptamine were isolated from P chilensis, and phenethylamine was detected in P tamarugo. At 0.50 mg ml(-1), both compounds showed DNA binding activity, with values of 18.5 and 11% respectively. The exudate of P alba showed a strong fi ee radical scavenging effect. The activity was related with the total phenolics content, consisting mainly of catechin. (C) 2000 Society of Chemical Industry.