Angiotensin Converting Enzyme Inhibitory Activity of Blue Lupin (Lupinus angustifolius) Proteins

Abstract

Objectives To evaluate the ACE inhibitory activity of protein hydrolysates derived from lupin Methods Methods used are spectrophotometer to assay the ACE activity, electrophoresis for estimation of protein molecular weight, and HPLC for determining products of ACE activity. Results The results revealed that the lupin flour was abundant in protein (43.3 g/100 g). Results from sequential Osborne extraction procedure showed that lupin protein comprised of 46% salt-soluble globulin, 27% water-soluble albumin, 18% alkaline-soluble glutelin and 7% alcohol-soluble prolamin fractions. Furthermore, lupin protein was rich in lysine but limiting in methionine. Hydrolysates prepared using Alcalase exhibited higher ACE inhibitory activities compared with those prepared using Flavourzyme, showing IC50 values ranging from 0.10 to 0.21 mg/mL. However, there was no significant difference in IC50 values between the hydrolysates prepared using Alcalase for 4, 10 and 16 h of hydrolysis times. Conclusions The results suggested that globulin was the major contributing protein fraction on ACE inhibitory effect in lupin protein. The lupin protein hydrolysates with potent ACE inhibitory activities can be incorporated into the daily diet to prevent hypertension. Funding Sources Ministry of Education Malaysia.

Bioactive Peptides from Lupinus spp. Seed Proteins-State-of-the-Art and Perspectives

“…Fractions in the molecular weight range of 2-3 and 3-5 kDa of blue lupin proteins also possessed ACE-inhibitory activity (IC 50 values from 450 to 600 µg/mL) [51]. Alcalase hydrolysates showed ACE inhibitory activities with IC 50 values ranging from 0.10 to 0.21 mg/mL [52].…”