Studies on the Composition of Protein and Lipid from Korean Walnut (Juglans regia L.)

한국산 호도의 단백질 및 지질의 조성에 관한 연구

We empolyed gel filtraction, polyacrylamide gel electrophoresis, amino acid autoanalyzer, thin layer chromatography for determining protein and lipid composition in walnut. The walnut contained 22.18% of crude protein and 64.23% of crude lipid. Glutamic acid (38.60%) was the major amino acid in soluble protein, followed by arginine and aspartic acid. The sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis showed 12 band in soluble protein of walnut, and collection rate of main protein fraction purified by Sephadex G-150 was 60.67%. The molecular weight for the main protein was estimated to be 43,000. The lipid fraction obtained by silicic acid column chromatography were mainly composed of about 93.05% neutral lipid, whereas compound lipid was only 7.0% level. Among the neutral lipid by thin layer chromatography, triglyceride was 82.05%, sterol ester and free fatty acid were 3.86% and 4.80%, repectively. The predominant fatty acids of total and neutral lipids were linoleic acid $(64.48{\sim}69.98%)$ and oleic acid $(13.89{\sim}15.36%)$. The major fatty acids of triglyceride separated from neutral lipid were linolenic acid (69.98%).

한국산 호도의 단백질 및 지방성분을 gel filtration, polyacrylamide gel electrophoresis, 아미노산분석기, thin layer chromatography 및 gas liquid chromatography에 의하여 분석하였고 그 일반성분은 조단백질의 22.18%, 조지질이 64.23%였다. 호도 단백질의 sodium dodecyl sulfate polyacrylamide gel electrophoresis에 의한 결과 12개의 band를 나타내었고 분획된 주단백질의 수득율은 60.67%였으며 이것의 분자량은 43,000이었다. 아미노산 조성은 17종류로써 glutamic acid가 38.60%로써 가장 많았고 다음은 arginine이 9.45%, aspartic acid가 6.55% 순으로 나타났으며 필수아미노산이 고르게 함유되어 있었다. 호도기름에는 중성지질이 93.05%이나 복합지질은 약 7.0%에 불과하였으며 중성지질의 성분으로써 82.05%가 triglyceride였고 sterol ester 및 유리지방산이 각각 3.85% 및 4.80%였다. 호도의 총지질과 중성, 당 및 인지질의 지방산 조성은 oleic acid 및 linoleic acid가 각각 $13.89{\sim}15.36%,\;64.48{\sim}69.98%$였고 중성지질에서 분별된 triglyceride의 지방산 조성은 linoleic acid가 69.98%로 가장 높은 함량이었다.