Effect of germination on antioxidant and ACE inhibitory activities of legumes

- Germination of selected legumes to improve bioactivity was investigated.
- Antioxidant release and proteolysis were higher at 40° than 30 °C germination.
- Highest ACE inhibition (>80%) were noted for germinated mung and soybean.
- Germinated legumes can be used in dietary management of hypertension.

Germinated legumes and sprouts can be potential dietary sources of bioactive compounds. In this study, selected commercially available legumes grains (chickpea, red lentil, mung bean, kidney bean and soybean), were germinated at 30 and 40 °C for 5 days and the antioxidant and ACE inhibitory activities were measured by the DPPH radical scavenging and in vitro ACE inhibition assay, respectively. Significant differences (p < 0.05) in total polyphenols, flavonoids and phenolic acids contents were noted within and between grains before and after germination. Antioxidant activity varied 14-35% after germination as a result of increase in antioxidant components. Lab-on-chip analysis showed proteolysis by inherent enzymes increased during germination at 40 °C by 2-4 fold leading to generation of peptides of different molecular sizes. Out of the legumes studied, germinated mung and soybeans can be used in the dietary management of hypertension as their protein hydrolysates showed >82% ACE inhibition reaching an IC50 value of 0.025 mg/mL.