An evaluation of amino acid, fatty acid and isoflavone composition in Korean peanut (Arachis hypogaea l.) seeds to improve the nutritional quality of breeding lines

Peanut is grown primarily for human consumption due to their favorable nutrient profile and functional compound such as isoflavone in seeds. The aim of this study was to evaluate the amino acid, fatty acid, and isoflavone profile in seeds of seven peanut cultivars (Suwon 88, Daewon, Daekwang, Seonan, Saedeul, Satonoka, and Pungan) grown in Korea. The protein and oil contents in peanut seeds varied at the range of 21.4 to 32.0% and 41.7 to 47.2%, respectively. The quantity of protein was relatively similar in all peanut cultivars except Pungan seeds. The result of amino acid analysis showed that Suwon 88, Daewon, and Seonan seeds had higher concentration of amino acid (Asp, Thr, Ser, Glu, Pro, Gly, Ala, Cys, Val, Met, Ile, Leu, Tyr, Phe, His, Lys, and Arg) than other peanut cultivars. However, the quantity of oil was higher in Suwon 88, Daekwang, Seonan, and Satonoka seeds, whereas the fatty acid profile analysis revealed that higher levels of oleic acid, arachidic acid, gondoic acid, behenic acids, and lower levels of palmitic, stearic, and linoleic acids were found in Saedeul seeds. In addition, the isoflavones, daidzin, genistin, and daidzein were higher in Satonoka (97.96, 63.19, and 33.8 μg/g, respectively) followed by Daewon. The results of the present study suggest that the cross among identified peanut cultivars, Satonoka (high yielding isoflavones), Seadeul (high yielding oleic acid), Suwon 88, Daewon, and Seonan (high yielding amino acid) would improve the nutritional and functional compounds of breeding lines.