• Applied Biological Chemistry
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• 제27권4호
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• pp.225-230
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• 1984

Chemical composition of dried roots of wild and cultivated Codonopsis lanceolata has been investigated. General composition was similar in both Codonopsis lanceolata. Free sugars from the root were fructose, glucose and sucrose. The contents of the sugars were higher in the cultivated than in the wild. Maltose was detected only in the cultivated and its level was 0.05%.. Free amino acids were consisted of 16 amino acids: lysine, histidine, arginine aspartic acid, threonine, serine, glutamic acid. proline, glycine, alanine, valine, methionine, isoleucine, leucine, tyrosine and phenylalanine. No significant difference in the contents was found between the wild root and the cultivated. Free fatty acids were palmitate, linoleate and linolenate, and the contents of those acids were higher in the cultivated root than in the wild. The contents of crude saponin were 1.5% in the wild root and 1.4% in the cultivated, respectively.

• Applied Biological Chemistry
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• 제31권1호
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• pp.7-12
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• 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 Fisheries and Aquatic Sciences
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• 제8권3호
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• pp.177-180
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• 1975

'Mideuduck', Styele clava, has been esteemed as one of the most tasty sea foods in the south coast of Korea. The free amino acids in Mideuduck were analysed by amino acid auto-analyser. In Mideuduck extract, taurine, proline, glutamic acid, glycine, alanine and serine were abundant, holding $32.8\%,\;17.6\%,\;11.9\%,\;11.2\%,\;8.9\%,\;7.1\%$ respectively of total amino acid content and followed by threonine, lysine, methionine in order. While valine, leucine, phenylalanine, isoleucine and histidine were poor ana aspartic acid, arginine and tyrosine were trace in content.

• Microbiology and Biotechnology Letters
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• 제17권2호
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• pp.88-93
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• 1989

To improve a new yeast strain capable of converting xylan to ethanol directly, we tried protoplast fusion between xylose fermenting yeast (Candida sp. X-6-41) and xylan assimilating yeast (Crypto-coccus sp. XB-33), finally selected the most promising two fusants (XFU-1 and XFU-2). As the optimum conditions for protoplast formation, the yeast cells were cultured to exponential phase in YPD and YPX containing 0.6M KCI, respectively, and then treated with zymolyase (0.25mg/$m\ell$), cellulase(4mg/$m\ell$) and 100mM 2-mercaptoethanol at pH 8 and 3$0^{\circ}C$. The protoplasts of parental auxotrophs were fused in the presence of 20mM CaCl$_2$and 40% polyethylene glycol(M.W.4000). The physiological and morphological characteristics of the fusants, such as assimilation of carbon sources, cell size, growth rate, xylanase activity and xylan fermentation ability were investigated. Xylanase activity of fusants that cultured in chemically minimal medium was higher than that of fusants that cultured in completed medium, because xylanase producing activity of xylose fermenting yeast(X-6-41) was inhibited by isoleucine.

• Journal of the Korean Chemical Society
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• 제41권6호
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• pp.304-312
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• 1997

Acetolactate synthase(ALS) is the common enzyme in the biosynthetic of valine, leucine, and isoleucine, and is the target of several classes of structually unrelated herbicides, including sulfonylureas, imidazolinones, and triazolopyrimidines. In an effort to develop new and desirable herbicides, we have synthesized 4,6-dimethoxypyrimidine derivatives, and examined their inhibitory activities on pea ALS. The most active compound was found to be K11570 and $IC_{50}$ value for K11570 was 0.2 ${\mu}M.$ The inhibition of pea ALS by K11570 was biphasic, showing increased inhibition with incubation time. The K11570 showed mixed-type inhibition with respect to substrate pyruvate. Dual inhibition analysis of K11570 versus sufonylurea herbicide Ally and feedback inhibitor leucine revealed that three inhibitors were competitive for binding to ALS. The arginine modified enzyme showed decreased inhibition by K11570, sufonylurea Ally, and leucine, in constrast to, tryptophan modification did not affect on the sensitivity of ALS to the inhibitors.

• KSBB Journal
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• 제22권5호
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• pp.278-281
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• 2007

The nutritional composition of Pleurotus nebrodensis fruiting body has been analyzed for medicinal and edible uses. Minerals of P. nebrodensis were found to be as follows potassium (1,612.96 mg/100 g), phosphorus (644.52 mg/100 g), magnesium (100.32 mg/100 g), sodium (97.84 mg/100 g), calcium (13.8 mg/100 g), iron (4.77 mg/100 g), zinc (4.32 mg/100 g), copper (0.88 mg/100 g) and manganese (0.55 mg/100 g) based on dry weight. Eighteen amino acids were found in P. nebrodensis. Among total amino acid, glutamic acid content was the highest (353 mg/100 g) and aspartic acid, leucine, arginine and alanine were followed. Concerning free amino acids, tryptophan, proline, alanine and isoleucine were dominant. The vitamin E content was the highest (285.31 mg/100 g), then vitamin C, niacin and vitamin $B_6$ were followed.

• BMB Reports
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• 제32권1호
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• pp.39-44
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• 1999

Pyruvate decarboxylase (PDC) catalyzes the conversion of pyruvate to acetaldehyde as the penultimate step in alcohol fermentation. The enzyme requires two cofactors, thiamin diphosphate (ThDP) and $Mg^{2+}$, for activity. Zymomonas mobilis PDC shows a strong preference for pyruvate although it will use the higher homologues 2-ketobutyrate and 2-ketovalerate to some extent. We have investigated the effect of mutagenesis of valine 111 and leucine 112 on the substrate specificity. V111 was replaced by glycine, alanine, leucine, and isoleucine while L112 was replaced by alanine, valine, and isoleucine. With the exception of L112I, all mutants retain activity towards pyruvate with $k_{cat}$ values ranging from 40% to 139% of wild-type. All mutants show changes from wild-type in the affinity for ThDP, and several (V111A, L112A, and L112V) show decreases in the affinity for $Mg^{2+}$. Two of the mutants, V111G and V111A, show an increase in the $K_m$ for pyruvate. The activity of each mutant towards 2-ketobutyrate and 2-ketovalerate was investigated and some changes from wild-type were found. For the V111 mutants, the most notable of these is a 3.7-fold increase in the ability to use 2-ketovalerate. However, the largest effect is observed for the L112V mutation which increases the ability to use both 2-ketobutyrate (4.3-fold) and 2-ketovalerate (5.7-fold). The results suggest that L112 and, to a lesser extent, V111 are close to the active site and may interact with the alkyl side-chain of the substrate.

• Korean Journal of Poultry Science
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• 제11권1호
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• pp.19-25
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• 1984

Proximate, calcium, phosphorus and amino acid composition were determined for sardine fish meal (SM), herring fish meal (HM), anchovy fish meal (AM), alaskapolack by-product meal (ABM) and file fish by-product meal (FBM) produced domestically. These fish protein sources were fed to adult male of meat type (Waren G) broiler chicks to determine the true availability of amino acids. The true availability of essential amino acids were closely related to various fish meals with a few exceptions (e.g. valine, methionine, isoleucine and leucine). Average true availability of essential amino acids (9 amino acids) were 95, 93, 93, 91 and 91 percent for AM, SM, FBM; HM and ABM, respectively. Significant differences in the true availability of each individual amino acid were observed among fish meal tested (P＜0.01). Lysine availability was low in HM, ABM and FBM whereas phenylalanine was the lowest in FBM and ABM, respectively. AM showed the highest true amino acid availability among all fish meal tested.

• Asian-Australasian Journal of Animal Sciences
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• 제15권12호
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• pp.1714-1718
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• 2002

Twelve prepubertal Karan Fries heifers (15 months, $167.7{\pm}13.5kg$) were divided into two equal groups. Group 1 was fed as per NRC requirements and group 2 was fed 20% more protein than group 1 heifers. The experimental feeding was continued until the onset of puberty in both the groups. Blood samples were collected at fortnightly intervals and analyzed for amino acids using HPLC. Group 1 and 2 heifers required $178.6{\pm}33.8$ and $152.8{\pm}33.2$ days of experimental feeding to exhibit first estrus resulting in total age at puberty as $639.4{\pm}27.3$ and $618.6{\pm}24.6$ days in the two groups respectively. The concentration of total amino acids averaged 4.40 and 4.89 mmol/l and those of non-essential amino acids (NEAA) was 2.32 and 2.49 mmol/l in groups 1 and 2, respectively. The concentration of plasma essential amino acids i.e. histidine, threonine, valine, methionine, isoleucine, leucine and phenylalanine were higher (p<0.01) in group 2 than group 1. Plasma concentration of large neutral amino acids (LNAA) was significantly higher in group 2 (1.28 mmol/l) than in group 1 (1.12 mmol/l). Increased levels of leucine, isoleucine and valine are implicated in increased follicular growth and development in prepubertal heifers and resulted in a 26 day earlier attainment of puberty by 26 days in an experimental period of six months in group 2 heifers. Increased concentrations of aspartate and tyrosine in group 2 heifers might be associated with the release of GnRH from the hypothalamus influencing LH release from anterior pituitary in such animals. It is therefore evident that increased availability of certain amino acids in heifers fed high protein diet might have led to early onset of puberty.

• Microbiology and Biotechnology Letters
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• 제32권2호
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• pp.101-109
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• 2004

In order to enhance the productivity of AVM $B_{la}$ produced by Streptomyces avermitilis as a secondary metabolite, we established a basic protocol necessary for protoplast fusion with high-producing strains as a fusion partner, and then obtained various kinds offusants by adopting a massive strain-development procedure (a miniaturized strain screening system). An alternative fusion method using UV and/or NTG mutation of protoplasts was developed to screen genetic recombinants without specific selectable markers. In this method, the mutants obtained by protoplast fusion after UV and/or NTG treatment (95% death rate) of the respective fusion partner (protoplasts of the respective mutants resistant against L-isoleucine antimetabolites such as O-methylthreonine and/or azaleucine) were regarded as DNA-recombined protoplast fusants. Notably it was demonstrated that most of the protoplast recombinants obtained by the UV mutation method were able to biosynthesize higher amount of AVM $B_{la}$ , reaching almost three times higher level (almost equal to the industrial productivity), compared to the average AVM Bla amount of the parallel mother strains.