• Applied Microscopy
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• v.51
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• pp.17.1-17.10
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• 2021

Our previous study on the binding activity between Cel5H and clay minerals showed highest binding efficiency among other cellulase enzymes cloned. Here, based on previous studies, we hypothesized that the positive amino acids on the surface of Cel5H protein may play an important role in binding to clay surfaces. To examine this, protein sequences of Bacillus licheniformis Cel5H (BlCel5H) and Paenibacillus polymyxa Cel5A (PpCel5A) were analyzed and then selected amino acids were mutated. These mutated proteins were investigated for binding activity and force measurement via atomic force microscopy (AFM). A total of seven amino acids which are only present in BlCel5H but not in PpCel5A were selected for mutational studies and the positive residues which are present in both were omitted. Of the seven selected surface lysine residues, only three mutants K196A(M2), K54A(M3) and K157T(M4) showed 12%, 7% and 8% less clay mineral binding ability, respectively compared with wild-type. The probable reason why other mutants did not show altered binding efficiency might be due to relative location of amino acids on the protein surface. Meanwhile, measurement of adhesion forces on mica sheets showed a well-defined maximum at 69±19 pN for wild-type, 58±19 pN for M2, 53±19 pN for M3, and 49±19 pN for M4 proteins. Hence, our results demonstrated that relative location of surface amino acids of Cel5H protein especially positive charged amino acids are important in the process of clay mineral-protein binding interaction through electrostatic exchange of charges.

• Korean Journal of Pharmacognosy
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• v.24 no.1
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• pp.38-46
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• 1993

Two kinds of gangliosides contained in deer horns were determined by integrating the peaks of TLC densitometry. Japanese deer horn originated from China showed the highest gangliosides among tested samples and the upper parts in deer horns showed higher gangliosides than the lower parts. In the case of graded samples, the best grade A showed the highest content and the worst grade E did the lowest content. Sixteen kinds of free amino acids were analyzed by auto amino acid analyzer. The lower region the deer horn was, the more the total content of free amino acids was and several kinds of amino acids were contained quite regularly.

• Journal of Food Hygiene and Safety
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• v.9 no.2
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• pp.81-87
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• 1994

This study was performed to investigate the detailed lipid content, lipid composition and amino acid composition of Semisulcospira gottschei tissues. Lipids of Semisulcospira gottschei tissues were extracted by the mixture of chloloform-methanol, fractionated into neutral lipids, glycolipids and phospholipids by silicic acid column chromatography and the composition of these lipid classes were determined by TLC and GLC. the amino acids in Semisulcospira gottschei tissues was analyzed by the amino acid auto analyzer. The total lipids content was 1.4% and the main components of the total lipids were neutral lipids 67.9%, glycolipids 19.3% and phospholipids 12.8%, respectively. The main fatty acids of total lipids were palmitic acid (20.5%), palmitoleic acid (16.45) and linolenic acid+eicosenoic acid (15.0%) and linoleic acid(13.1%), the main fatty acids of glycolipids were palmitic acid (41.9%), palmitoleic acid (19.7%) and oleic acid (11.7%), and the main fatty acids of phospholipids were linolenic acid+eicosenoic acid (55.1%), oleic acid (17.3%) and palmitic acid (11.4%). The main amino acids were glutamic acid (16.0%) and aspartic acid (11.1%).

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.173-181
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• 2000

To understand the influences of NaCl concentration and fermentation temperature on the ripening process of low salt fermented squids, squid with 5%, 7% and 9% salt were fermented at 10$\^{C}$ and 20$\^{C}$. The result of the changes of volatile basic nitrogen and free amino acids during the fermentation of squids are as follows. As a result of the observations on the changes of physicochemical components during the fermentation process of the low-salted squids, all the pH, VBN and NH$_2$-N were increased and therefore the fermentation was promoted. Considering the changes of net components according to the fermentation, ATP (Adenosine triphosphate) and ADP (Adenosine diphosphate) lost and could not be detected among the nucleotides and their related compounds. Besides, AMP (Adenosine monophosphate) existed only in the initial stage and inosine, hypoxanthine were the main components of nucleotides and their related compounds. Nonvolatile organic acids are mainly lactic acid, acetic acid and also they occupied more than 80%. Seeing the composition of free amino acid, the major amino acids are proline, arginine, methionine, alanine and glutamic acid.

• The Korean Journal of Mycology
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• v.22 no.4
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• pp.338-342
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• 1994

Amino acids of Pleurotus ostreatus in various cultural media(rice straw, sawdust and cotton waste) were analyzed to recognize the compositional differences depending on pileus size and portions(pileus and stipe) Total amino acids of rice straw were a little less than that of sawdust and cotton waste. Seventeen amino acids were identified and quantified. Among the amino acids glutamic acid was higest and cystine was lowest. The amino acid contents depending on the pileus size was higest in $3{\sim}7\;cm$ of rice straw, under 3 cm of sawdust, over 7 cm of cotton waste, respectively. The content of them was found to be higher in pileus than stipe.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.3
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• pp.249-252
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• 1986

This quantitative analysis was carried out in order to investigate the isolation and identification of total amino acids and free sugars in Lycii fructus by using amino acid autoanalyzer and HPLC. 17 kinds of amino acids were analyzed by amino acid autoanalyzer, that is, aspartic acid, proline, glyclne, analine, cystine, valine, methionine, isoleucine, leucine, tyrosine, phenyla lanine, histidine, lysine, arginine, threonine, serine and glutamic acid. Threonine (3,745mg/100g) was the richest among them and total amounts of the essential amino acid, which was 53.93% of total amino acids, was 10,773mg/100g. Free sugars isolated by HPLC wet·e glucose, fructose and saccharose.

• Fisheries and Aquatic Sciences
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• v.9 no.2
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• pp.49-56
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• 2006

We evaluated changes in the nutritional composition of Mideodeok Styela clava harvested during the months of January, March, and May 2005. Glutamic acid, aspartic acid, arginine, leucine, and lysine were the most dominant amino acids present. Ratios of essential amino acids to nonessential amino acids were comparable to those of many fish species, with values ranging from 0.55 to 0.61 and 0.66 to 0.67 for muscle of Mideodeok from Geoje and Tongyeong, respectively. Mideodeok seems to be a suitable source of important fatty acids as it contains high levels of polyunsaturated fatty acids. Eicosapentanoic acid EPA; 20:5n-3 and docosahexanoic acid DHA; 22:6n-3 were the most dominant fatty acids, ranging from 20.0 to 22.3% and 16.5 to 17.9% in muscle, and 20.3 to 23.2% and 15.2 to 18.8% in tunic, respectively. The total mineral fraction of Mideodeok was 22.2-27.3% of dry matter. Sodium, calcium, magnesium, and potassium were the most dominant minerals in both muscle and tunic.

• Journal of the Korean Society of Food Culture
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• v.23 no.1
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• pp.121-129
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• 2008

To produce buckwheat sprouts, buckwheats were germinated at $23{\pm}2^{\circ}C$ up to 8 days in total darkness. In proximate analysis, moisture content increased from 13.87% of buckwheat groats to 93.75% of buckwheat sprouts on the 8th day of germination. On dry weight basis, lipid and ash contents increased like as protein content increased from 13.45% to 21.82% while carbohydrate content decreased due to enzyme hydrolysis. Amino acids were rich in glutamic acid, aspartic acids, and lysine, and also the ratio of the essential amino acids to total amino acids increased from 26.84% to 36.84%. Vitamin C did not exist in buckwheat groats but its content has continued to increase as far as 99.56 mg/100 g buckwheat sprouts. Rutin continued to increase by HPLC analysis from 4.71 mg/100 g buckwheat groats to 1,524 mg/100 g buckwheat sprouts. In analysis of organic acids, oxalic, maleic, and citric acids were commonly found in buckwheat sprouts. Fagopyrin was found almost none in buckwheat sprouts. In conclusion, the conversion of buckwheat seeds into sprouts through germination in darkness results in physically different final product with nutritional changes such as higher content of rutin, generation of vitamin C, abundance of the essential amino acids, and the existence of fagopyrin on very little.

• Journal of the Korean Applied Science and Technology
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• v.28 no.4
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• pp.517-525
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• 2011

Squid ink was added to the low salt fermented squid by 4% of concentration and ripened at $10^{\circ}C$ for 6 weeks and at $20^{\circ}C$ for 28 days. The effect of the squid ink on the titrable acidity and free amino acids of low salt fermented squid were investigated. The results are as follows; The titrable acidity in the salt fermented squid without addition of the squid ink was continuously decreased except for the salt fermented squid with 9% salt content till the latter stage of the ripening, had larger decreasing range than treatment groups. Seeing the composition of free amino acid, the major amino acids are proline, arginine, glutamic acid. leucine and glycine.

• Archives of Pharmacal Research
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• v.9 no.1
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• pp.15-18
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• 1986

Various naturally occuring methylated amino acid derivatives were resolved on high performance liquid chromatography (HPLC), using o-phthadialdehyde as a fluorogenic reagent. We separated .$\varepsilon$-N-monomethyllysine, $\varepsilon$-N- dimethyllysine, and $\varepsilon$-N-acetyllysine from lysine derivatives. $N^{G}$-Monomethylarginine and $N^{G}$-dimethylarginine were separated from arginine derivatives. However, $\varepsilon$-N-monomethyllsine and $\varepsilon$-N-trimethyllysine, $N^{G}$, $N^{G}$-dimethylarginine and $N^{G}$, $N^{G}$-dimethylarginine were not resolved under the conditions employed. S-Methylmethionine, S-methylcysteine, and 1-N-methylhistidine or 3-N-methylhistidine were clearly separated from their reference amino acids, even though 1-N-methyl-and 3-N-methylhistidine coul not be separated.