The characteristics of the bioactive compounds of isoflavone and study of antioxidant activity of the ethanol extract of tempeh made of jack bean (Canavalia ensiformis)

Abstract

Istiani Y, S Handajani, A Pangastuti. 2015. The characteristics of the bioactive compounds of isoflavone and study of antioxidant activity of the ethanol extract of tempeh made of jack bean (Canavalia ensiformis). Biofarmasi 13: 50-58. The objectives of the research were to find out: (i) the contents of the isoflavone compounds of daidzein, genistein, glisitein, and factor-2, and (ii) the antioxidant activity of jack bean and its tempeh product. The material used for the research was jack bean with the treatment of the whole and chopped seed size and length of fermentation (0, 1, 2, 3, 4 days) compared with the ethanol extract of the soybean and its tempeh product and several natural antioxidants (α-tocopherol, ß carotene, and Vitamin C) and BHT synthetic antioxidant. The method used to extract the isoflavone compounds was maceration, and the method used to identify the isoflavone compounds was that of HPLC. The test of antioxidant activity used the method of DPPH. The analysis of the data of the test of antioxidant activity used the method of General Linear Model -Univariate and Compare Means -One-Way Anova. The largest total content of the isoflavone compounds of the tempeh made of the whole and chopped jack bean took place in the 1-day fermentation, that is, 0.786% and 0.590% while the largest total content of the isoflavone compounds of the tempeh made of the soybean took place in the 2-day fermentation, that is, 1.812%. The highest antioxidant activity of the tempeh made of the whole and chopped jack bean and soybean took place in the 3-day fermentation, that is, 77.32%, 68.63%, and 81.43% respectively. The antioxidant activity of the tempeh made of the soybean was relatively similar to that of BHT, that is, at the range of 81%, and the antioxidant activity of the tempeh made of the whole jack bean was relatively similar to those of vitamin C and α-tocopherol, that is, ranging from 75% to 77%. The oxidant activity of the tempeh made of the chopped jack bean was lower compared to those of soybean, natural antioxidant (Vitamin C and α-tocopherol and BHT) significantly different that is 69%, and ß carotene (45%) had the lowest antioxidant activity.