• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.3
• /
• pp.320-324
• /
• 2003

The protein hydrolysis with 6 M formic acid containing 0.3% tryptamine was a superior method for amino acid analysis of standard amino acid and protein than 6 M HCI containing 0.3% tryptamine. The recoveries of standard amino acid after acid hydrolysis were more accurate in the 6 M formic acid hydrolysis than 6 M HCI hydrolysis, especially recovery of tryptophan showed higher values of 1.5 times than that of 6 M HCI hydrolysis. The results of analysis on the standard protein, bovine serum albumin, showed very similar values compared to the sequence analysis reported in the literature for the 6 M formic acid hydrolysis than 6 M HCI hydrolysis, especially in the tryptophan recovery as standard amino acid recovery. Butylthiocarbamyl - trimethylsilyl (BTC - TMS) derivatives of 22 standard amino acids were successfully resolved DB-17 capillary column. Excellent reproducibility of standard amino acid recovery and composition of bovine serum albumin were obtained with BTC-TMS derivatives.

• Applied Biological Chemistry
• /
• v.31 no.1
• /
• pp.7-12
• /
• 1988

The degermed Japonica and J/Indica brown rites were successively milled to give 4.4%(fraction I), 4.7%(fraction II) and 5.9%(fraction III) yield of flour, with the remaining as residual kernel. The amino acid composition of the protein in the milled fractions was similar, except serine and histidine. With some amino acids, particularly phenylalanie, glycine and isoleucine, differences among varieties were much greater than among fractions of the same rice. The content of lysine was the highest in fractions I and II, whereas isoleucine showed the opposite trend to lysine. The first and second limiting amino acids of all fractions were lysine and threonine, respectively. No varietal differences in the distribution of fatty acids within the kernel were observed.

• Korean Journal of Food Science and Technology
• /
• v.30 no.1
• /
• pp.35-41
• /
• 1998

Essential amino acid composition of seventy eight medicinal herbs marketed in Korea was analyzed of the basis of their dried weight. From the results analyzed, it was shown that Alisma orisntale (S.) J. (1,911.5 mg%), Foeniculum vulgare M. (1,090.8 mg%), Artemisia princeps P. (1,073.6 mg%) and Typha latifolia L.(956.1 mg%) contain in threonine. Alisma orisntale (S.) J. (2,523.3 mg%), Nelumo nucifera G. (1,984.7 mg%) and Foeniculum vulgare M. (1,553.8 mg%) contain in lysine. Nelumo nucifera G. (738.3 mg%), Alisma orisntale (S.) J. (635.2 mg%) and Foeniculum vulgare M. (507.7 mg%) contain in methionine. Nelumo nucifera G. (2,496.9 mg%), Alisma orisntale (S.) J. (2,295.6 mg%) and Coix lachrymajobi L. var. M. S. (2,222.5 mg%) contain in leucine. Nelumo nucifera G. (1,624.6 mg%), Alisma orisntale (S.) J. (1,432.7 mg%) and Xantnium strumarium L. (1.371.7 mg%) contain in isoleucine. Alisma orisntale (S.) J (1,791.0 mg71), Nelumo nucifera G. (1,570.6 mg%) and Xantnium strumarium L. (1,498.7 mg%) contain in phenylalanine.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.14 no.2
• /
• pp.66-71
• /
• 1981

In order to study the decomposition process of glycogen and protein of oyster during fermentation with salt, and the relationship between their breakdown products, the amounts of free reducing sugars and lactic acid were determined, and amino acid compositions were analysed. In addition, the amount of the available lysine which may help us to estimate the reaction of the free reducing sugars with the free amino acids was also determined. Glycogen and protein were gradually decomposed to free reducing sugars and lactic acid, and free amino acids, respectively, and the available lysine was slightly decreased during the fermentation process. Glutamic acid, aspartic acid, lysine and proline were relatively rich in the amino acid com-position of raw oyster protein while amino acids such as tryptophan, methionine, histidine and tyrosine were poor. It was noted that the decreased amino acids in the protein from the fermented oyster were valine, histine, isoleucine and lysine. As a respect to the free amino acids, proline, taurine, glycine, glutamic acid and alanine were abundant in the raw oyster and reached up to $69\%$ of the total fret amino acids. In the fermented oyster, proline, glutamic acid, glycine, alanine, aspartic acid and lysine were prevalently contained and marke about $65\%$ of the total free amino acids. The contents of free amino acids such as lysine, arginine, aspartic acid, glutamic acid, cysteine, isoleucine and tyrosine increased during fermentation while those of taurine, proline and leucine decreased.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.11 no.3
• /
• pp.37-40
• /
• 1982

Fifteen free amino acids except tryptophan, proline and cystine were identified from Korean red ginseng and dried ginsengs from Korea, America and Canada using by high performance liquid chromatography (HPLC). Arginine was 72.6% of total free amino acids in the red ginseng and 48.2 to 68.7% in the dried ginsengs. The content of each free amino acid was lower in the red ginseng than in Korean dried ginseng. Most free amino acids in Korean dried ginseng showed higher content than those in American and Canadian ones. Tryptophan, proline cystine, methionine and phenylalanine were not detected in the extracts of red ginseng and of Korean white ginseng. Arginine was highest in these extracts and all free amino acids were higher in the white ginseng extract.

• Korean journal of food and cookery science
• /
• v.10 no.2
• /
• pp.126-130
• /
• 1994

This study was to investigate the amount of protein and essential amino acid in 19 fast-foods. fast-food samples were freeze dried, then assayed for protein and eight essential amino acids by Kjeldahl and amino acid autoanalyzer method. A.S.(amino acid score) based on FAO/WHO(1973) provi-sional Pattern & C.S.(chemical score) based on whole e99 Pattern(1972) were calculated from the amount of essential amino acid of fast-foods. The 1st limiting amino acid of the tested fast-foods was found to be SAA based on both whole e99 Pattern& FAO/WHO Provisional Pattern.

• Korean Chemical Engineering Research
• /
• v.50 no.1
• /
• pp.93-105
• /
• 2012

Activity coefficients and solubilities of L-Valine and L-Proline in aqueous solutions containing each of four electrolytes such as NaCl, KCl, $NaNO_3$ and $KNO_3$ were measured at 298.15 K. The measurements of activity coefficients were carried out in the electrochemical cell coupled with two ion-selective electrodes (cation and anion), and the solubilities were measured by the gravimetric analysis of saturated solutions in equilibrium with the solid phase of amino acid. The measured activity coefficients of electrolytes and amino acids were correlated with the theoretical thermodynamic model presented in the previous work [Korean Chem. Eng. Res. 48(4), 519(2010)]. It was found that the activity coefficients of amino acids and electrolytes described based on the our previous model were well agreeable with experimental data. Also the experimental solubility data of L-Valine and L-Proline were successfully correlated with the thermodynamic relation mentioned in the previous work.

• Journal of the Korean Chemical Society
• /
• v.39 no.4
• /
• pp.257-265
• /
• 1995

Free amino acids were isolated from milk and their absolute amounts were determined by reversed phase high performance liquid chromatography after derivatization with dansyl chloride. The determination of D- and L-amino acids was based on achiral separation on a C18 column. It was found that milk contained totally 41.00 mg DL-amino acids in 100 mL milk. The level of D-amino acids to L-amino acids was determined by a column-switching system combining an achiral reversed phase separation and chiral chelate additive. The chiral separation was carried out with addition of the chiral Cu(N-benzyl-L-proline)2 chelate to the mobile phase in reversed phase liquid chromatography. It was found that the determination of 16 different amino acids is feasible in the milk sample with a C18 column separation and 12 D-amino acids out of the 16 amino acids can be determined via the column-switching system with chiral separation. 2.05% of D-glutamic acid and 2.93% of D-alanine were found in milk.

• Journal of Life Science
• /
• v.16 no.7 s.80
• /
• pp.1123-1126
• /
• 2006

The nutritional composition of Fomitopsis pinicola (F. pinicola) fruiting body has been analyzed for medicinal and edible uses. The contents of crude fibers, carbohydrates, crude protein, moisture, crude fats and ashes were 43.3%, 26.3%, 12.8%, 12.6%, 3.3% and 1.7%, respectively. Eighteen amino acids were found in F. pinicola. Among total amino acids, glutamate content was the highest (457 mg/100 g dry mushroom) and arginine, glycine, valine, aspartate and isoleucine were followed. Concerning free amino acids, glutamine, arginine, trytophan, and glutamate were dominant. The vitamin E content was the highest (276 mg/100 g dry mushroom), then vitamin H and vitamin B, were followed. The mineral contents were as follows: K 165.06 mg, P77.57 mg, Mg 46.11 mg, Fe 21.56 mg, and Ca 16.90 mg based on 100 g dry mushroom.

• Korean Journal of Food Science and Technology
• /
• v.12 no.2
• /
• pp.88-96
• /
• 1980

Reaction conditions in the amino-carbonyl reaction, and the effect of amino acids on the reactivity of amino-carbonyl reaction were investigated. Results obtained are as follows : 1. When the pH of the reaction mixture was increased above the isoelectric point of an amino acid, a significant increase in the color intensity was observed. 2. The color intensity increased gradually up to 1 : 1 of the molar ratio of reactants. This result was interpreted to show that sugar and free amino group combined in 1 : 1 ratio. 3. Amino-carbonyl reaction showed a significant time and temperature-dependences. The activation energy at 0.2 M glucose and 0.2 M glycine system was 37.5 Kcal/mole. 4. Among amino acids tested, glycine, lysine and $\beta$-alanine caused a significant increase in the color intensity, but acidic amino acids showed the least color intensity. The latter was interpreted to show that one of carboxyl groups of acidic amino acid has an inhibiting effect on the reactivity of the amino group. 5. The color intensity of sugars tested was in the order of xylose>arabibose>fructose>glucose>maltose>lactose.