• Korean Journal of Food Science and Technology
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• v.8 no.2
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• pp.63-69
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• 1976

The changes in lysine availability during soybean fermentation were determined by the chemical analysis method as well as the biological methods with rat. The FDNB-reactive lysine determined by the difference (TLMI) method indicated that cooking and Meju fermentation reduced the lysine availability of soybean, but the subsequent ripening restored the availability to the same level of the raw soybean. On the other hand, the Biological Value, NPU, NER and the Relative lysine availability of the rat experiments showed a general decrease in the lysine availability of soybean during the ripening process as well as Meju fermentation.

• Journal of Nutrition and Health
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• v.4 no.1
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• pp.63-67
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• 1971

The nitrogen content and free amino acids were determined from the saute of mong bean paste which is one of the important protein sources on Korean diet. During the saute' process of mong-bean paste, valine, r-aminobutyrate, glutamine, arginine, methionine, and unknown acids were lost, but, proline, lysine, homoserine, and tyrosine were detected.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.126-132
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• 1991

Nutritional factors affecting the urinary excretion of acid-soluble peptides(ASP) in rats were studied using protein-free diet, gluten diet, casein diet, and gluten supplemented with lysine and threonine(GLT) diet. The content of urinary ASP was lowest in protein-free diet group among the four kinds of diets above. But the amino acid pattern of urinary ASP in the four dietary groups were similar each other, suggesting that urinary ASP is mainly from endogenous origin under these nutritional conditions. The efficiency of dietary protein utilization was significantly lower in gluten diet than that of casein diet or GLT diet. Those findings suggest that the rate of urinary excretion of ASP-form amino acids can be employed as an index of protein metabolism, particularly as a simple index in the assessing the status of protein nutrition.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.287-294
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• 1983

Change of color, browning index, soluble protein, reducing sugar content, and available lysine were monitored for raw and extruded barely powders during four months of ambient and accelerated storage temperatures with $A_w$ of 0.31 and 0.71, respectively. Loss of whiteness and soluble browning pigments increased with increased $A_w$ and temperature. The raw sample had an increased rate of browning intensity than the extruded samples. Among the extruded samples, the added sucrose sample had the lowest rate of browning during storage. Loss of reducing sugar content in all samples increased with increased $A_w$ and temperature. The loss of soluble protein and of the available lysine also increased with increased $A_w$ and temperature. The loss of reducing sugar and of the available lysine was at least partly due to the Maillard browning reaction. These results have important implications in teh processing and storage of raw and extruded burleys.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.336-341
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• 2002

This experiment was conducted to evaluate the lysine cell mass (LCM) as a dietary fish meal (EM) protein replacer in juvenile Israeli carp, Cyprinus carpio. Fishmeal, a major animal protein source in the control diet, was replaced by tCM on the protein equivalent base, Fish averaging 1,7 $\pm$ 0.1 g (Mean $\pm$ SD) fed one of nine diets containing isonitrogenous and isocaloric basis of $38\%$ crude protein and 15.2 kJ available energy/g diet: control, $100\%$ $FM; LCM_20$, $80\%$ $FM+20\%$ $LCM; LCM_40$, $60\%$ $FM+40\%$ $LCM; LCM_60$, $40\%$ $FM+60\%$ $LCM; LCM_100$, $100\%$ $LCM; LCM_20$l, $80\%$ $FM+20\%$ $LCM+0.07\%$ $Lysine; LCM_40$l, $60\%$ $FM+40\%$ $LCM+0.14\%$ $Lysine; LCM_60$l $40\%$ $FM+60\%$ $LCM+0.22\%$ Lysine; LCM_100l, $100\%$ LCM+$0.35\% Lysine. After 6 weeks of feeding trial there was no significant difference in weight gain (WG), feed efficiency (FE), protein efficiency ratio (PER) and specific growth rate (SGR) among fish fed control and $LCM_20$ (P>0.05), while fish fed $LCM_40,\;LCM_60,\;LCM_100,\;LCM_40l,\;LCM_60l\;and\;LCM_100l$ diets had a significantly lower WG, FE, PER and SGR than did fish fed control diet (P<0.05). There was no significant difference in WG, PER and SGR among fish fed control and $LCM_20$l diets (P>0.05), while fish fed $LCM_20$l S had a significantly lower FE than did fish fed control diet (P<0.05). No significant difference was observed in hematocrit and condition facto, among fish fed nine diets (P>0.05). Therefore, these results indicated that LCM could replace FM up to $20\%$ and dietary synthetic lysine supplementation did not show any positive growth effects in juvenile Israeli carp.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.333-338
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• 1986

Compositions of protein and amino acid in the muscle of crucian carp, Carassius carassius, and snakehead, Channa argus, were determined by amino acid autoanalyzer, and the protein subunits composed of sarcoplasmic and myofibrillar proteins were also analyzed by sodium dodecylsulfate (SDS) polyacrylamide gel electrophoresis. The crucian carp muscle contained about $14.7\%$ of protein, and the protein was composed of $32.6\%$ in sarcoplasmic, $62.0\%$ in myofibrillar, $4.9%$ in alkali soluble and $0.6\%$ in stroma protein. The snakehead muscle, on the other hand, contained about $16.1\%$ of protein, and $30.7\%,\;64.1\%,\;4.7\%\;and\;0.4\%$ in the above order. The sarcoplasmic and myofibrillar proteins were composed of 10 and 19 subunits respectively, in the crucian carp, and 12 and 18 subunits in the snakehead. The total amino acid compositions in the muscle of the crucian carp and snakehead were found to be very similar except lysine and glutamic acid. The major amino acids of their muscle protein were lysine, glutamic acid, arginine and aspartic acid in order. In free amino acid content of the crucian carp, histidine occupied $52\%$ of the total free amino acid, and glutamic acid, glycine and taurine did $85\%$ in case of snakehead.

• Korean Journal of Food Science and Technology
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• v.5 no.4
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• pp.210-214
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• 1973

This study analyses and compares the amino acid composition and available lysine content between Korean fermented soybean Meju and its products as well as home-made and commercially made products. The protein quality of the products was evaluated by the result, and the biological value of the proteins was estimated by using the regression equation for chemical score to biological value as calculated by B.O. Eggum. The amino-N content of soybean is found to be 85% of the total nitrogen content and is reduced to approximately 75% in the fermented products except home-made soysauce, where as the content of ammonia-N and other N-compounds is increased. The difference in protein quality between home-made and commercially made products is not found to be significant. The protein quality of soybean is not damaged greatly in the making of Meju but is seriously damaged during the long periods of ripening. After the ripening the chemical score of the products' protein is reduced to approximately one half of the original soybean protein and the available lysine content to $1/3{\sim}1/2$.

• Korean Journal of Food Science and Technology
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• v.7 no.1
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• pp.22-29
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• 1975

Conditions for submerged culture of Agaricus campestris var. bisporus and the chemical composition of its mycelium were investigated. In shaking culture with TGY basal medium at $27{\sim}30^{\circ}C$, pH tended to increase upon culture period, mycelial growth was the highest on 12th day, with relatively high nitrogen content of 7% and sugar in the medium disappeared almost at the end of culture period. As a nitrogen source, ammonium phosphate (dibasic) gave relatively high mycelial yield and the addition of yeast extract gave rise to better results. As a carbon source, glucose was the best, fructose, maltose, lactose and sucrose gave the same results, and soluble starch was utilized slightly. Mushroom mycelium contained 48% of protein, 8 free amino acids including arginine, histidine, lysine, isoleucine, leucine, phenylalanine, proline, tyrosine and its protein consisted of most essential amino acids, with relatively high contents of lysine and threonine. Therefore, mushroom mycelium deserves to be a high quality protein food.

• Journal of Aquaculture
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• v.14 no.3
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• pp.197-203
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• 2001

To replace fish meal (FM) in the diet of Nile tilapia, Oreochromis nloticus, different levels of Iysine cell mass (LCM) were added to diet on protein equivalent base. fish averaging 3.0 g fed one of nine diets containing isonitrogenous and isocaloric basis of 35% crude protein and 15.3kJ available energy/g diet: $LCM_0, 100% FM: LCM_{10}, 90% FM+10% LCM, LCM_{20}, 80% FM+20% LCM; LCM_{30}, 70% FM+30% LCM; LCM_{40}, 60% FM+40% LCM; LCM_{30}l, 70% FM+30% LCM+lysine; LCM_{30}ln, 70% FM +30% LCM + lysine +NaOH; LCM_{40}lan, 60% FM+40% LCM+lysine+arginine; LCM_{40}/lan, 60% FM+40% LCM+lysine+arginine+NaOH.$. After 8 weeks of feeding trial, there were no significant differences in weight gain (WG) and specific growth rate (SGR) among fish fed LCM$_{0}$ (control diet), LCM_{10}, LCM_{30}, LCM_{40}, LCM_{30}l, LCM_{30}ln, LCA_{40}la and LCM_{40}lan diets (P>0.05)$, while fishes fed $LCM_{20} diet were significantly higher than those fed LCM_{0}, LCM_{30}, LCM_{40}, LCM_{40}la and LCM_{40$}lan diets (P<0.05). There were no significant differences in feed efficiency (FE) and protein efficiency ratio (PER) among fish fed control diet, $LCM_{10}, LCM_{20}, LCM_{30}ln, LCM_{ 40}la and LCM_{40}$lan diets (P>0.05), while fishes fed control diet were significantly higher than those fed $LCM_{30}, LCM_{40} and LCM_{40}l diets (P<0.05)$. Positive effects were not shown in WG and SGR with supplementation of amino acids (lysine & arginine) and neutralizatio, while FE and PER from fish fed $LCM_{40}la and LCM_{40}lan diets were significantly higher than those fed LCM_{30}, LCM_{40} and LCM_{30}$l diets (P<0.05). Hence, LCM can replace FM up to 40%, and dietary suppl-ementacon and neutralization of amino acids showed positive effects, when FE and PER were considered in juvenile tilapia diet.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.482-487
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• 1999

Periodate-oxidized soluble starch and maltohexaose reacted with ${\alpha}-NH_2$ group of free amino acids and ${\varepsilon}-NH_2$ group of peptidyl lysine. The result shows that periodate-oxidized soluble starch and maltooligosaccharides reacted with protein and formed Schiff base between CHO group of oxidized sugar and ${\varepsilon}-NH_2$ group of surface lysine of protein molecule. Carbon and hydrogen composition of sweet potato ${\beta}-amylase$ modified with oxidized soluble starch increased and it's nitrogen composition decreased. Carbohydrate contents of sweet potato ${\beta}-amylase$ modified with oxidized soluble starch were 13.2% (pentamer), 13.4% (monomer), and with oxidized maltohexaose were 9.7% (pentamer), 9.3% (monomer) by $phenol-H_2SO_4$ method. Alpha-amino group of N-terminal, and ${\varepsilon}-NH_2$ group of lysine, of sweet potato ${\beta}-amylase$ were reacted with oxidized soluble starch by dinitrophenylation were 70% (pentamer), 73% (monomer) and 33% (pentamer), 26% (monomer), respectively, in comparison with native enzyme.