• Journal of Life Science
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• v.9 no.4
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• pp.341-347
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• 1999

Insects use chitinolytic enzyme to digest chitin in the exoskelton during the molting process. We have isolated and sequenced a chitinase-encoding cDNA from the silkworm, Bombyx mandarina, compared its sequenced with genes encoding chitinolytic enzymes from other sources. The insert DNA in the clone is 2,675 nucleotides long with an open reading frame of 1,695 uncletides that encodes a protein of 565 amino acids with a molecuar weight of 63.4 kDa. The 3' -untranslated region of 889 nucleotides is AT-rich and contains two putative polyadenylation signals. The N-terminal sequence of the encoded protein contains numerous hydrophobic residues characteristic of a leader peptide. The amino acid alignment revealed that the endo-$\beta$-N-acetylglucosaminidase had 83% and 97% homology with M. sexta and B. mori, respectively. The deduced amino acid had two highly conserved region at the amino acid residues 97-111 and 139-148 that were related to the existing chitinase.

• Bulletin of the Korean Chemical Society
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• v.15 no.9
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• pp.795-799
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• 1994

Kinetic studies of the deacylation reactions of p-and m-nitrophenyl esters of (R or S)-${\alpha}$ -methoxyphenylacetic acid were performed in ${\beta}$ -CD, mono-6-deoxy-6-[N-(2-aminoethyl)]amino-${\beta}$-CD (${\beta}$-CDen) and mono-6-deoxy-6-[N-(2-aminoethyl)-2-aminoethyl] amino-${\beta}$-CD (${\beta}$-CDdien) media. The binding constants (K) of the substrates to the hosts and the rate constants ($k_{\varphi}^{CD}$) for the complexed substrates were determined. $k_{\varphi}^{CD}$ values are highly dependent on the hosts and the substrates, whereas differences in K values among them are modest. The p-nitrophenyl esters show larger acceleration by -${\beta}$-CDen and -${\beta}$-CDdien than the corresponding m-isomers, while the m-isomers are more reactive than the p-isomers in -${\beta}$-CD media. This is taken as an indication that the amino groups attached to the primary side of -${\beta}$-CD participate in the deacylation reaction.

• Bulletin of the Korean Chemical Society
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• v.13 no.3
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• pp.311-314
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• 1992

A new monocyclic ${\beta}-lactam$ analogue, sodium (3R,4S)-3-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyi minoacetamido]-4-methoxymethyl-2-azetidinone-1- sulfonate (3) was synthesized from L-aspartic acid. Starting from L-aspartic acid, (S)-1-benzyl-4-benzyloxycarbonyl-2-azetidinone (7) was synthesized in four steps by following the established procedures and converted into (3R,4S)-3-amino-1-t-butyldimethylsilyl-4-methoxym ethyl-2-azetidinone (13) in six steps. Acylation of the amino group of 13 with $2-amino-{\alpha}$ -(methoxyimino)-4-thiazoleacetic acid, desilylation, and sulfonation with sulfur trioxide-pyridine complex followed by ion exchange afforded sodium (3R,4S)-3-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyi minoacetamido]-4-methoxymethyl-2-azetidinone-1- sulfonate (3). Antibacterial activities of this ${\beta}$ -lactam compound 3 were, however, found to be quite low compared to cefotaxime.

• Environmental Analysis Health and Toxicology
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• v.4 no.3_4
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• pp.1-6
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• 1989

The effects of his ($\beta$-amino-ethyl-oxo) oxalate and bis ($\alpha$-amino-methyl-oxo) oxalate on the toxicity of lead acetate in rast were examined. Rats were given intraperitoneally at the dose of lead acetate 45 mg/kg. The exposure of lead acetate showed the 70% decrease of ALAD ($\delta$-amino levulinic acid dehydratase) activity in red blood cell. In vivo 122 mg/kg administration of bis ($\beta$-amino-ethyl-oxo) oxalate and bis ($\alpha$-amino-methyl-oxo) oxalate showed the 50% increase of ALAD activity, whereas 149 mg/kg administeration of Ca-EDTA had no effect. In vitro, the same results were obtained. Both compounds had hemolytic activity at concentrations higher than that required for showing the 50% ALAD activity increase in vivo.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1634-1641
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• 2005

Generally, dietary fibre (DF) includes lignin, non-starch polysaccharides (NSP) and resistant starch (RS). In monogastric species, low levels of dietary fibre in the diet are associated with various diseases and high levels reduce nutrient digestibilities. In this study, the effects of different types and levels of NSP (soluble: $\beta$-glucan, insoluble cellulose) and resistant starch on mucin secretion and endogenous nitrogen and amino acid losses in pigs were investigated. A total of 25 five-week-old weaner pigs (9.5 kg${\pm}$1.5 kg), were randomly allocated to each of five experimental diets. Different levels of purified barley $\beta$-glucan (BG) extract (5 or 10% of $Glucagel^{(R)}$ $\beta$-glucan, providing 4 or 8% of BG in the diet), and resistant starch (RS) (8.3 or 16.6% of Hi-$Maize^{TM}$, providing 5 or 10% RS in the diet) were substituted for wheat starch in a purified diet in which enzymatically-hydrolysed casein was the sole source of protein. The diets were fed for 21 days. No statistically significant difference between treatments (p>0.05) was observed for growth performance and organs weights. No difference in ileal starch digestibility was observed between pigs on the cellulose or $\beta$-glucan diets. However, as the level of resistant starch in the diet increased the ileal starch digestibility decreased (p<0.05). The inclusion of resistant starch in the diet (5 or 10%) did not increase mucin production when compared with the cellulose-only diet. However, as the level of beta-glucan in the diet increased, both crude mucin in the digesta dry matter and per kg dry matter intake increased (p<0.05). Pigs fed the diet containing 8% of beta-glucan had higher endogenous loss flow than those fed the diets including 5 or 10% of resistant starch or 4% of $\beta$-glucan. In conclusion, dietary inclusion of resistant starch increased the level of starch reaching the large intestine without any effect on mucin secretion, or endogenous nitrogen or amino acid losses content in the small intestine. The addition of $\beta$-glucan to a diet containing cellulose increases both mucin secretion and endogenous amino acid and nitrogen losses in the small intestine.

• Journal of the Korean Chemical Society
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• v.39 no.2
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• pp.123-126
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• 1995

• Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.16-23
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• 2007

Myostatin (GDF8) is a growth factor that limits muscle tissue growth and development in vertebrates. We isolated a myostatin-like gene (Py-MSTN) from the marine invertebrate, the scallop Patinopecten yessoensis. Py-MSTN was highly expressed in the adductor muscle and in the gill unexpectedly. Amino acid analysis showed that Py-MSTN has 49% amino acid sequence identity and 64% similarity to human myostatin (Hs-MSTN), and 42% identity and 61% similarity to myoglianin, the only invertebrate homolog. These results indicated that Py-MSTN may be functionally similar to the vertebrate MSTN than the invertebrate homolog. Phylogenetic analysis suggested that Py-MSTN is an ancestral form of vertebrate MSTN and GDF11 and does not belong to other $TGF-{\beta}$ family members. Molecular modeling showed that Py-MSTN exhibits a similar tertiary structure to mammalian BMP7, a member of $TGF-{\beta}$ family. In addition, the amino acid residues which contact extracellular domain of the receptor were relavively conserved. Given these results, we propose that Py-MSTN is a functionally active member of the $TGF-{\beta}$ family and is involved In muscle growth and regulation.

• Journal of Ginseng Research
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• v.14 no.1
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• pp.21-26
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• 1990

The chemical composition and stabilities of the purified ginseng invertase were investigated. The purified enzyme was found to be a glycoprotein composed of 80.2% protein and 19.7% total sugar. The protein component of the enzyme was composed of acidic amino acid (9.3%), basic amino acid (48.9%), nonpolar amino acid (21.4%), polar amino acid (20.4%) and 6.1% S-containing amino acid. It showed especially high contents of histidine and serine. The enzyme was inactivated almost completely by the treatment with some proteases (papain, pepsin. trypsin, pancreatin and microbial alkaline pretense) and protein denatllrants (8M urea and 6M guanidine-HC1), bolt not with glyrosidase (${\alpha}$-amylase, ${\beta}$-amylase. glcoamylese and cellullase). btonosaccharides sllch as glilrose, fructose, galactose and mannose did not exert any influence on the enzyme activity. The activity of the enzyme was inhibited by Ag+, Mn2+, Hg2+, Zn2+ and Al3+, whereas Ca2+, Mg2+, Ba2+ and Fe3+ gave rather activating effects on the enzyme activity. The enzyme was relatively stable in the VH range of VH 6 and 8, and at the temperatures below 35$^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• v.13 no.3
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• pp.343-344
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• 1992

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.150-156
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• 2011

Germinated barley, instead of glutinous rice, was used to make health-enhancing fermented red pepper paste. The proximate components of commercial glutinous rice red pepper paste (CGRPP) and germinated barley red pepper paste (GBRPP) were analyzed during fermentation. The sensory characteristics and ${\gamma}$-amino butyric acid (GABA) contents of CGRPP and GBRPP were evaluated. The contents of ${\beta}$-glucan and GABA showed the highest value after 48 hrs of germination. During the fermentation, the contents of GABA in GBRPP increased up to 28 days and then decreased. During sensory evaluation, the consumer liked the GBRPP more than CGRPP. The GABA contents were increased during fermentation and GABA contents of GBRPP were twice as much as that of CGRPP. These results suggest that the GBRPP can have consumer acceptance for its health benefits and taste and can therefore become commercialized.