Comparative studies on the inhibitory action of some legume seeds, potato tubers, and bran against human and bovine proteinases

Abstract

Inhibition of human trypsin and chymotrypsin by proteinase inhibitors of plant origin was studied using the juice from the small intestine, without separation of the two enzymes, and synthetic amide substrates (BAPA, GLUPHEPA). The results were compared with the inhibition of the corresponding bovine enzymes. Extracts and preparations from legume seeds (13 Papilionoideae, 2 Caesalpinioideae, 3 Mimosoideae), potato tubes and bran were used as inhibitors; 9 of the seed extracts studied inhibited human chymotrypsin more and human trypsin less than the bovine enzymes. In similar tests 5 seed extracts inhibited the two human enzymes more than the bovine enzymes, whilst only one extract inhibited the two human enzymes less than the two bovine enzymes, and another inhibited human trypsin more and human chymotrypsin less than the bovine enzymes. In particular, human chymotrypsin was between two and twelve times as strongly inhibited as the bovine enzyme by some two thirds of the species studied, sometimes exhibiting chymotrypsin-inhibitory activities usually observed only with trypsin. Inhibitor preparations from the above legumes and two non-leguminous plant foods exhibited similar results.

Isolation and characterisation of four trypsin-chymotrypsin inhibitors from lentil seeds

“…The di †erences in speciÐc inhibitor activity against HCT between LCI-DE fractions and puriÐed inhibitors are thought to be related to the di †erent composition of human duodenal juice containing various chymotrypsins (HCT IA, IB and II) of di †erent stability and/or being di †erently inhibited (Weder 1986). Repeated determinations showed that the results of HCT inhibitor determinations varied considerably, as already observed earlier with other samples (Belitz et al 1982, Weder and1991c). No speciÐc HCT inhibitors nor inhibi-Hauner tors with unusually high HCT inhibitor activity could be detected in the LCI-DE fractions by electrophoresis.…”

“…chymotrypsin (EC 3.4.21.1) by Mansfeld et al (1959). In a comparative study of the inhibitory activity of the seeds of 18 legumes, lentils have been found to inhibit human chymotrypsin (HCT) much more than bovine chymotrypsin (BCT), human trypsin (HT) and bovine trypsin (BT) (Belitz et al 1982). Furthermore, the occurrence of four isoinhibitors in all the 38 lentil samples tested (Weder et al 1985), the isolation and characterisation of the principal inhibitor from a local market lentil sample (Weder et al 1983) and that of two trypsin-chymotrypsin inhibitors from Italian red lentils (Mueller and Weder 1989) have been reported.…”

Factors affecting thein vitro protein digestibility of chickpea albumins

“…Our results showed that the decrease in TIA as a result of heat treatment was not related to an increase in the rate of IVPD (Table 3). The lack of improvement in IVPD could be due to different causes, such as changes in the localisation of amino acid residues specific to digestive enzymes (lysine, arginine, phenylalanine, tryptophan and tyrosine)22 and the presence of a more compact structure caused by the formation of new disulphide bonds, which impairs protease access to labile peptide bonds 30. 31…”

Inhibitor activities of chickpeas (Cicer arietinum L) against bovine, pocine and human trypsin and chymotrypsin

“…Higher levels of inhibitor activity against BT than against BCT have previously been reported (Singh and Jambunathan 1981 ;Belitz et al 1982). Moreover, mean values for both BT and BCT inhibition were higher for desi genotypes compared to those of kabuli, although the data was not evaluated for degree of significance (Singh and Jambunathan 1981 ;Saini 1989).…”