engleski

Comparative study of legumes as sources of isoflavones

Isoflavones are group of phytochemicals associated with numerous benefits to the human health like prevention of cancer, cardiovascular diseases, osteoporosis and menopause symptoms. The major source of isoflavones in the diet is soybean, although many other legumes also contain these compounds. The aim of this study was to determine the content of individual isoflavones in different annual legume species collected in the Republic of Croatia and compare with soybean. Seven annual legume species: common bean (Phaseolus vulgaris L.), faba bean (Vicia faba L.), lentil (Lens culinaris Medic.), white lupin (Lupinus albus), chickpeas (Cicer arietinum L.), cowpea (Vigna unguiculata L.) and grass pea (Lathyrus sativus) were analysed and were compared with soybean (Glycine max (L.) Merr.).The ground samples of annual legume grains were extracted with ethanol and hydrolysed into their corresponding aglycones with hydrochloric acid. Isoflavones were identified by HPLC method, according to retention time compared with standards and quantified by the internal standard (β- naphthol) method. Total isoflavone content was expressed as sum of four isoflavones (aglycone): daidzein, genistein, glycitein and formononetin. The results showed wide variation in isoflavones content within and between species. The most dominant isoflavone, in all examined grain, was daidzein. The highest content of daidzein was found in grass pea accession S1 (123.61 mg/100g DM). In individual accessions of some examined legume species glycitein, genistein and formononetin was not detected. The accession Gradištanac (bean) had the highest content of glycitein and formononetin isoflavones (5.73 and 17.88 mg/100g DM), while the landrace faba bean from Pakovo selo had the highest content of genistein (67.96 mg/100g DM). The content of total isoflavones of 19 accessions of eight legume species ranged from 11.47 to 151.82 mg/100g DM, and the soybean species had the highest mean content with 120.9 mg/100g DM, while the greatest variation found within a grass pea species. The present study showed that examined legume species may be potential sources of isoflavones next to soybean.

annual legumes ; grains ; isoflavones

nije evidentirano