A Review on Factors and Processing Methods Affecting Antihypertensive Properties of Legumes, and Antihypertensive Properties of Selected Legumes

Hypertension is one of the major risk factors which leads to cardiovascular diseases, and the typical treatment for hypertension is drug therapy. However, as there are side effects to drug therapy, there has been an increase in research on legume proteins as biopeptides have shown antihypertensive effects. Many species of legumes have been cultivated for consumption as they are a good source of protein, carbohydrates, minerals, vitamins, and dietary fiber. Bioactive compounds of legumes potentially improve factors that affect antihypertensive properties, such as angiotensin-converting enzyme (ACE) inhibition activity, renin inhibition activity, and γ-aminobutyric acid (GABA) production. The processing method of enzymatic hydrolysis can improve ACE inhibition activity, as can be seen with horse gram, pigeon pea, and lentil hydrolysates containing potent ACE inhibitory peptides of Thr-Val-Gly-Met-Thr-Ala-Lys-Phe, Val-Val-Ser-Leu-Ser-Ile-Pro-Arg, and Asn-Ser-Leu-Thr-Leu-Pro-Ile-Leu-Arg-Tyr-Leu, while pigeon pea and kidney bean hydrolysates have shown good renin inhibition activity. Fermentation can also be used to process legumes as potent ACE inhibitory peptide Val-Val-Ser-Leu-Ser-Ile-Pro-Arg was identified from fermented pigeon pea, while kidney beans and lentils demonstrated good GABA production through natural fermentation and fermentation with microbial cultures. The germination processing method could also help improve ACE inhibition activity as horse gram has shown good inhibition activity. In vivo study of pigeon pea, kidney bean, and lentils showed potential antihypertensive properties as a significant lowering of systolic blood pressure of test subject was observed. Research done on the structure and function of antihypertensive properties of legumes can help in the development of functional food products which will be beneficial to human health.