Change of Nitrogenous Compounds in Peanut(Arachis hypogaea L.) Seeds during Germination

The change of nitrogenous compounds in the seeds of peanut cultivar Bairihong(Arachis hypogaea L) during96 h of germination was investigated.The results showed that the protease activity of peanut seeds germinated for 96 h was increased by 54.82 times as compared with that of ungerminated dry seeds and the degree of protein hydrolysis was15.01%at the end of the germination period.SDS-PAGE pattern showed the partial disappearance or loss of conarachin(50-66 kD)and acidic arachin(38-49.9 kD) together with the appearance of a series of smaller molecular weight subunits.The total nitrogen content was not significantly altered,but the quantity of protein nitrogen fell by 15.88%with a concomitant increase in the content of non-protein nitrogen(from 2.84 mg/g to 9.20 mg/g) after 96 h of germination.The contents of limiting amino acids(Trp + Val),the ratios of essential amino acids and of sulfur-containing amino acids to total amino acids and essential amino acid index(EAAI) increased with prolonged germination period,suggesting that germination can significantly enhance the quality of peanut protein.