Radiation effect on ascorbic acid and riboflavin biosynthesis in germinating soybean.

The influence of irradiation on biosynthesis of ascorbic acid and riboflavin in germinating soybean seeds in tap and distilled water at ambient (25-35 degrees C) conditions was investigated. Ascorbic acid was not detectable in the original seeds and the initial level of riboflavin was 3.3 micrograms/g. The rate of synthesis of these vitamins increased with increasing germination time up to 72-96 hr followed by a decreasing pattern depending upon the treatment. The effect of irradiation and germination on the synthesis of these vitamins was statistically significant (P less than 0.01). Maximum amounts of ascorbic acid 16.2 and 15.0 mg/100g (fresh weight basis) were found in the 0.10 kGy sample after 72 hr of germination in tap and distilled water, respectively. However, a radiation dose of 0.20 kGy resulted in the development of maximum values of riboflavin, 30.0 and 27.0 micrograms/g (dry weight basis) on germination in tap and distilled water respectively.