• Applied Biological Chemistry
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• v.47 no.4
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• pp.403-408
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• 2004

We studied active substances like crude cell wall components, crude protein, composing amino acids and free amino acids including orinithine cycle-related amino acids such as asparagine, ornithine and citrullin in fully ripe fruits of Korean native squash, Cucurbita moschata Poir. Crude protein content of 'Jeju 2' was the highest with $2,830\;{\mu}g/g$, while 'Sangju' was the lowest with $1,319\;{\mu}g/g$. Regarding the contents of crude cell wall components, fruit 'Kanghaw' was the highest with 2,961 mg% while 'Namhea' was the lowest with 1,582 mg%. Pectin contents of crude cell wall components were the highest in 'Kanghaw' (2,198 mg%) followed by 'Jeju 2' (2,178 mg%) and 'Jeju l' (1,461 mg%). The main contents of amino acids in squash were glutamic acid, aspartic acid, lysine, leucine and valine, which comprised to be more than 50% of total amino acid contents. Especially, in 'Jeju 2' aspartic acid and threonine were not detected. In fully ripe fruits, a total of 34 kinds of free amino acids were detected including 8 kinds of essential amino acids (histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine and valine). More than 50% of the total free amino acids were aspartic acid and asparagine, and also all varieties were detected in ornithine, citrullin, and arginine, which are related to Ornithine cycle. There was a big difference in the contents of arginine in all varieties whereas the contents of ornithine and citrullin were very similar. 'Teaan' 29.34% was 7 times higher than 'Namhea' 4.30% in regards to arginine contents.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.409-413
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• 2004

We have studied quality changes of fully ripe fruit of Korean native pumpkin 'Yangsan' regarding the following parameters: pH, sugar content, weight, water content, contents of crude protein and amino acids during 60 days storage at room temperature. As the results, there was no changes in sugar contents according to the storage period, but pH was changing to a little acidic direction with slight decrease in weight and water content. Contents of total crude proteins and comprising amino acids were increased during the storage period. The main contents of amino acids of the Korean native pumpkin, Yangsan, were glutamic acid (15.5%), aspartic acid (10.1%), lysine (8.7%), valine (7.5%), leucine (7.1%) and alanine (6.6%), which were not highly influenced during storage period. Additionally we have investigated the content of free amino acids and color changes during processing of Yangsan under high temperature at $121^{\circ}C$ and high pressure at $1\;kg/cm^2$. In fully ripe fruits, a total of 29 kinds of free amino acids were detected including 8 kinds of essential amino acids (histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine and valine). More than 35% of total free amino acids were aspartic acid (20.3%) and asparagine (15.4%); ornithine, citrullin, and arginine, which are related to Ornithine cycle, were also detected in fully ripe fruits. But when treated with high temperature and high pressure, glutamic acid and arginine were decreased rapidly whereas ammnonium chloride was relatively increased. Moreover "b" value as yellow color indicator was decreased from 17.45 to 9.14 while treated for 60 minutes with high temperature and pressure, caused by the degradation of ${\beta}-carotene$ and other yellowish pigments in Yangsan.