• Applied Biological Chemistry
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• v.38 no.6
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• pp.502-506
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• 1995

A Bacillus strain which produces ${\beta}-galactosidase$ with high transgalactosylation activity, was isolated from soil and tentatively designated as Bacillus sp. A1. When ${\beta}-galactosidase$ from Bacillus sp. A1 reacted with 40% (w/w) lactose, transgalactosylation ratio reached up to 90% at the 70% conversion of the initial lactose. The biosynthesis of the enzyme in Bacillus sp. A1 required lactose as an inducer and was repressed by glucose. Observing that the addition of amino acids to culture medium resulted in enhancing, to a significant extent, both the growth and the enzyme production of the strain, yeast extract and commercially available hydrolysates of protein were examined for the suitability as amino acid source. As it turned out, SMP, an enzymatic hydrolysis product of soybean protein from Fuji Oil Co.(Japan), was the most suitable for optimization of the culture medium. When Bacillus sp. A1 was cultured in the presence of 0.5% SMP and 2% lactose, the enzyme activity increased up to $1.8\;U/m{\ell}-broth$.

• Journal of the Korean Wood Science and Technology
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• v.11 no.1
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• pp.18-24
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• 1983

Oak mushroom (Lentinus edodes Sing.) has been used as one of vegetable foods for a long time, because it has particular odour, taste and abundant nutritive material. Its cultivation has been done extensively, but its checmical analysis of the components is curiously limited. It is the purpose of this study to analyse its component chemically and to get basic data in terms of nutrition science. The results are summarized as follows: 1. It was analysed that the total number of amino acid is 17 different kinds, mainly glutamic acid. 2. All the essential amino acids which are lecucine, lysine, threonine, tryptophan, valine, phenylalanine, isoleucine, tyrosine, and methionine were found in this chemical analysis. 3. The seven kinds of vitamins are analysed, which are A(${\beta}$-carotene), $B_1$ (thiamin), $B_2$(riboflavin), C(ascorbic acid), E(${\alpha}$-tocopherol), Niacin, choline chloride.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.795-799
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• 1989

This study was carried out to hydrolyze lactose in commercial milk by ${\beta}-galactosidase$ from Kluyveromyces fragilis and to compare some physicochemical properties of yoghurts made from control and lactase-treated commercial milks. Quantitative analysis of sugars was performed by gas liquid chromatograph (GLC) on trimethylsilyl (TMS) derivatives. In commercial milk, 94.6% of lactose was hydrolyzed after 2 hours incubation at $40^{\circ}C$ with 6.0 units/ml of ${\beta}-galactosidase$. pH, titratable acidity and viable cell number of yoghurt made from lactase-hydrolyzed (LH) commercial milk were 4.1, 1.04% and $6.5{\times}10^8/ml$ of Str. thermophilus, $8.9{\times}10^8/ml$ of L. bulgaricus after 8 hours incubation at $40^{\circ}C$, respectively, The total contents of amino acid were 2.63% in control and 2.19%. in LH yoghurt. The total contents of free amino acid were 26.95 mg% in control and 17.55mg% in LH yoghurt. Analysis of free fatty acids resulted in that the contents of short chain fatty acids in LH yoghurt were a little higher than those in control. Both in control and LH yoghurt, the palmitic acid content was highest and that was followed by oleic and myristic acid.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.161-165
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• 2012

Antimicrobial peptides of insects are found and reported as immune defence system against infectious agents. The peptides are produced by fat body cells and thrombocytoids, a blood cell type. Defensin is 38-45 amino acids long and consists of an ${\alpha}$-helix linked by a loop to an antiparallel ${\beta}$-sheet. Defensin from a bumblebee, Bombus ignitus, is known to comprise 52 amino acid residues. This peptide consists of two ${\alpha}$-helixes; ACAANCLSM and KTNFKDLWDKRF and one ${\beta}$-sheet; GGRCENGVCLCR. We carried out antibacterial activity test by radial diffusion assay against Staphylococcus aureus (Gram positive), Escherichia coli (Gram negative), Pseudomonas syringae (Gram negative), Candida albicans (fungi), MDRPA, MRSA, and VRE (antimicrobial resistant microbes) with synthetic oligopeptides from Peptron (Daejeon, Korea). The predicted curtailment fragment (GGRCEVCLCR-$NH_2$) for ${\beta}$-sheet had strong antibacterial activity when internal amino acids were removed. But, curtailment fragments (ACAANCLSM-$NH_2$ and TNFKDLWDKR-$NH_2$) of ${\alpha}$-helix were not showed antibacterial activity. These synthetic oligopeptides were showed the great activity against Gram positive and negative bacteria.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.1-10
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• 1987

For surveying of constituents concerning the flavor of the dried tomato fruits, nonvolatile components such as minerals, sugars, free amino acids, nucleotides and lipids were analyzed and determined. Potassium, calcium and phosphorus were the major conatituents of ashes, but trace amounts of cadmium and lead were determined. Glucose and fructose were the major constituents in sugars, and the latter slightly showed higher value than the former. The content of total free amino acids was 8322.5mg%, and that of the major components such as asparagine, aspartic acid, urea. glutamic acid, ${\beta}-alanine$ and ${\gamma}-aminobuthyric$acid showed 58.01% to the total amount. The nucleotides were composed of CMP, UMP, GMP and IMP, and CMP among them showed the highest value as about 58.07% to the total amount. On the other hand, IMP showed the lowest one. The major components of the total fatty acids from the saponifiable fraction in the lipids were $C_{18:2}$, $C_{18:1}$ and $C_{16:0}$ and those of the total sterols from unsaponifiable one were stigmasterol and ${\beta}-sitosterol$.

• Journal of Marine Bioscience and Biotechnology
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• v.10 no.1
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• pp.1-8
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• 2018

The objective of this study was to purify and characterize the ${\beta}-secretase$ inhibitor from enzymatic hydrolysates of blackfin flounder muscle, for development of a novel anti-dementia agent that may be used in the drug or functional food industries. ${\beta}-secretase$ inhibitory peptide was purified from various enzymatic hydrolysates of blackfin flounder muscle. Among six enzymatic hydrolysates, the Alcalase hydrolysate revealed highest ${\beta}-secretase$ inhibitory activity. Consecutive purification of the blackfin flounder muscle hydrolysate using Sephadex G-25 column chromatography and octadecylsilane C18 reversed phase HPLC techniques were used to isolate a potent ${\beta}-secretase$ inhibitory peptide composed of 5 amino acids, Leu-Thr-Gln-Asp-Trp (MW: 526.7 Da). The $IC_{50}$ value of purified ${\beta}-secretase$ inhibitory peptide was $126.93{\mu}M$. Results of this study suggest that peptides derived from blackfin flounder muscle may be beneficial as anti-dementia compounds in functional foods or as pharmaceuticals.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.510-515
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• 2005

Pseudomonas cepacia BY21 was found to produce glutaryl acylase that is capable of deacylating glutaryl-7-aminocephalosporanic acid (glutaryl-7-ACA) to 7-aminocephalosporanic acid (7-ACA), which is a starting material for semi-synthetic cephalosporin antibiotics. Amino acids of the reported glutaryl acylases from various Pseudomonas sp. strains show a high similarity (>93% identity). Thus, with the known nucleotide sequences of Pseudomonas glutaryl acylases in GenBank, PCR primers were designed to clone a glutaryl acylase gene from P. cepacia BY21. The unknown -subunit gene of glutaryl acylase from chromosomal DNA of P. cepacia BY21 was cloned successfully by PCR. The -subunit amino acids of P. cepacia BY21 acylase (GenBank accession number AY948547) were similar to those of Pseudomonas diminuta KAC-1 acylase except that Asn408 of P. diuminuta KAC-1 acylase was changed to Leu408.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.397-403
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• 1997

This study examined the changes of chemical components in Dongchimi when ginseng and pineneedle were added 0.1% and 0.3%, respectively. Those were fermented at room temperature for the first day and at 4$^{\circ}C$ from the second to 29th day. The contents of reducing sugar was significantly increased during fermentation, and showed the highest content in Dongchimi added pineneedle. The contents of proteins were also increased in the Dongchimi with pineneedle during 8 days of fermentation, while the others increased throughout 29 days of fermentation. The contents of non-volatile organic acids were 2.79~4.80 mg/100 ml at the end of fermentation, and the content of lactic acid was the highest among them. Free sugars of the Dongchimi were composited sucrose, glucose and fructose, and the contents of those were in the range of 227.4~247.0 mg/100ml in 8 days of fermentation, then increased to 705.2~943.7mg/100ml in 29 days. the Dongchimi contained 17 kinds of free amino acids except lysine, arginine were the majority of them, and sarcosine, $\beta$-aminoisobutyric acid and ${\gamma}$-aminoisobutyric acid were the major portion of amino acid dervatives.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.299-304
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• 2014

The objective of this study was to elucidate the physicochemical characteristics of gelatin extracted from jellyfish Rhopilema hispidum. We investigated the proximate composition, amino acids, gel strength, gelling/melting points, dynamic viscoelastic properties, and viscosity of jellyfish gelatin. Jellyfish gelatin contained 12.2% moisture, 1.5% lipid, 2.1% ash, and 84.8% protein. Glycine, hydroxyproline, proline, and alanine were the predominant amino acids. The gelatin showed a gel strength of 31.2 kPa, a gelling point of $18.0^{\circ}C$, and melting point of $22.3^{\circ}C$. The gelatin was composed of ${\alpha}_1$-chain, ${\alpha}_2$-chain, ${\beta}$-chain, and ${\gamma}$-chain. During cooling and heating process, jellyfish gelatin showed lower elastic modulus (G') and loss modulus (G") values than mammalian gelatin. Jellyfish gelatin did not show superior rheological properties to mammalian gelatin, like other fish gelatin; however, it can be used in various food and cosmetic products not requiring high gel strength.

• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.2
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• pp.169-174
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• 2010

Hydrolysate silk fibroin (HSF) is a fibrous protein composed of parallel $\beta$-structures and is made from pure silk elements including 18 amino acids, with glycine, alanine, and serine comprising of over 80% of the amino acids. Numerous studies have documented a range of effects of HSF, including moisturizing, antioxidant activity, nervous system disorders, and many more. We investigated whether HSF has anti-obesity effects in vitro. The effects of HSF inhibition on lipid accumulation and acceleration of lipid degradation in 3T3-L1 cells were studied. Treatment of 3T3-L1 cells with HSF caused significant inhibition of cell viability, an increase in glycerol release, and a decreased in adipocyte differentiation. Moreover HSF stimulated downregulated of adipogenic enzyme expressions (PPAR${\gamma}$ and C/EBP${\alpha}$) and up-regulated of fatty oxidation enzyme expressions (CPT-1 and UCP-2). Based on these results, hydrolysate silk fibroin can be suggested as a potential therapeutic substance as part of a prevention or treatment strategy for obesity.