• Korean journal of food and cookery science
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• v.27 no.6
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• pp.815-823
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• 2011

This study was carried out to analyze the change of major nutrient components of spaghetti squash by boiling. The moisture, crude protein, fat, ash and carbohydrate contents in fresh squash were 94.2%, 0.6%, 0.1%, 0.7% and 4.4% respectively as against 95.1%, 0.5%, 0.1%, 0.5% and 3.8% in boiled squash. The decrease in protein and ash contents of the boiled sample were found to be significant. Major component of the minerals were potassium and the fresh and boiled squash had the contents of 330 mg and 256 mg, respectively. There were no differences of dietary fiber between the fresh and boiled squash. Beta-carotene contents of the fresh and boiled spaghetti squash were $0.69{\mu}g$ and $2.22{\mu}g$, respectively. The contents of tocopherol were decreased as like 4.3 mg and 2.0 mg. A total of 17 kinds of amino acids were isolated from squash and they were decreased by boiling and the high content of amino acids in order were aspartic acid, glutamic acid, arginine, lysine, and leucine in raw squash. Particularly, total amino acid of fresh squash were 6,739.5 mg per 100 g edible portion and higher than that of boiled squash(4,820.3 mg). Total polyphenolic compound of the fresh squash from $297.3{\mu}g/mg$ was slightly decreased to $253.3{\mu}g/mg$ by boiling.

• Food Science and Preservation
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• v.12 no.3
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• pp.275-281
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• 2005

This study was carried out to investigate the cathepsin B inhibition effect by Achyranthes japonica N. root extract in vitro. The methanol/$H_{2}O$(4:1, v/v) extract was fractionated by ethyl acetate(F1), chloroform(F2), chloroform/methanol(3:1, v/v)(F3) and methanol(F4). The yield of F4 in Achyranthes japonica N. root was $8.27\%$. As an index material of Achyranthes japonica N. root, 20-hydroxy ecdysone was detected by TLC, and HPLC and it's content was $0.33\%$. Three isolates(F1, F3, F4) showed the cathepsin B inhibition activity, and F4 showed the highest inhibition activity among them. In the inhibition activity on cathepsin B, leupeptin, 20-hydroxy ecdysone and F4(at the same concentration of 20-hydroxy ecdysone.) were 92, 88 and $97\%$ on BANA($N{\alpha}$-benzoyl-DL-arginine ${\beta}$-naphthylamide) substrate, and 62, 36 and $67\%$ on CLN($N{\alpha}$-CBZ(carbobenzlyoxy)-L-lysine p-nitrophenyl ester HCI) substrate, respectively.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.158-164
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• 1998

Crystal structural analyses of the API-TLCK complex revealed that the ${\epsilon}$-amino group (NZ) of the lysyl part of TLCK forms hydrogen bonds with OD1 of $Asp^225$ which is a substrate specificity determinant of API, OG of $Ser^214$, O of $Ser^214$, OG1 of $Thr^189$, and O of $Thr^189$ l89/. The ${\beta}$-carboxyl oxygen of $Asp^225$ forms hydrogen bonds with the NE1 of $Trp^182$. From these observations, it is thought that besides $Asp^225$, $Thr^189$, $Ser^214$, and $Trp^182$ may also contribute to the steric specificity for lysine and high proteolytic activity of API. The side-chain hydroxyl groups of $Thr^189$ and $Ser^214$ were removed to elucidate the role of these hydrogen bonds in the $S_1$-pocket. The $k_{cat}$/$K_m$ of T189V, S214A, and T189V.S214A were decreased to 1/4, 1/3, and 1/46, respectively, of the value for native API. The decreased activities were mainly due to the increase of $K_m$. The CD and fluoroscence spectra of the three mutants were similar to those of wild-type API. With regards to the kinetic parameters ($K_i\;and\;k_2$) of mutants for the reaction involving TLCK and DFP, $k_2$decreased by increase of $K_1$ only. These results suggest that the decreased catalytic activity of these mutants is caused by the partial loss of the hydrogen bond network in the $S_1$-pocket. On the other hand, the similarity of enzymatic properties between W182F and the native enzyme suggests that the hydrogen bond between OD2 of $Asp^225$ and NE1 of $Trp^182$ is not directly related to the reaction of $Asp^225$ with the substrate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.94-101
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• 2011

Squid (Todarodes pacificus) is processed as dried or seasoned-dried products and its catch gradually increased from 270,298 M/T in 2005 to 367,940 M/T in 2008 in Korea. Squid processing by-product (viscera) was usually discarded as a waste resulting in environmental problem. In order to utilize squid viscera for more value-added products, a natural squid seasoning was developed by fermenting with Aspergillus oryzae koji. Squid viscera at 5, 10 and 15% salt concentrations with fixed levels of 5% koji and 30% water was fermented at room temperature. The quality properties of squid fermented products such as amino-N, TMA, VBN, total viable cell count, pH and total acidity were determined at different fermentation periods. The contents of amino-N, TMA, and VBN of squid seasoning at 5% salt concentration fermented for 14 days were the highest. Based on amino-N content, squid viscera at 5% koji fermented for 14 days was selected for further assays: the content of moisture, crude protein, crude lipid, crude ash, and carbohydrate were 5.98, 35.19, 33.08, 11.30, and 14.45%, respectively. The content of glutamate, alanine, leusine and lysine were 7.06, 12.34, 9.90 and 10.22%, respectively. The $IC_{50}$ values of DPPH scavenging and $\beta$-glucuronidase inhibitory activity were 12.89 and 12.58 mg/mL, respectively. A natural squid seasoning was manufactured by mixing fermented squid viscera and an ingredient. Based on the results of sensory evaluation, the fermented squid viscera seasoning was almost equal to other natural complex seasonings such as anchovy, cow meat, and fisheries seasoning.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.551-558
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• 1992

The extracellular endoinulase from Streptomyces sp. 556 was purified and characterized, The culture broth was fractionated by ammonium sulfate saturation followed by DEAE-cellulose column chromatography and 5ephadex G-200 gel filtration, The ultimately purified fraction revealed a single band in 7.5% polyacrylamide gel electropherogram. The purified enzyme showed the maximal activity at pH 5.5-6.0 and $50^{\circ}C$, but lost 93% of inulase activity after 30 min incubation at $55^{\circ}C$ . The essen.tial amino acid residue for catalytic activity appeared to be tryptophan. This endo inulase was activated by $Mn^{2+}$, whereas inactivated by $Ag^{+}$, $Hg^{+}$, $Cu^{2+}$, $Zn^{2+}$, $Fe^{3+}$ and $Mo^{6+}$ EDTA and 8-hydroxyquinoline inhibited the enzyme so that the enzyme was considered to be a metalloenzyme. The Km value for inulin was 0.287 mM, and no invertase or $\alpha$-glucosidase activity was found in the enzyme.

• Environmental Mutagens and Carcinogens
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• v.26 no.4
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• pp.125-132
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• 2006

Previous studies showed that epigallocatechin gallate(EGCG) have substantial effects of suppressing the N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)-initiated cell transformation process on the bases of foci formation frequency and loss of anchorage dependency. In this study we tried to clarify the molecular mechanism of suppressing the cell transformation process. Mouse cell line balb/c 3T3 A31-1-1 was exposed 2 days to MNNG followed by 15 days 12-O-tetradecanoylphorbol-13-acetate(TPA) treatment for our transformation process. EGCG was added after the time point of 24 hours exposure to TPA and incubated for 19 days. 2029 genes were selected in our transformation process that showed fold change value of 1.5 or more in the microarray gene expression analysis covering the mouse full genome. These genes were found to be involved mainly in the cell cycle pathway, focal adhesion, adherens junction, TGE-$\beta$ signaling, apoptosis, lysine degradation, insulin signaling, ECM-receptor interaction. Among the genes, we focused on the 631 genes(FC>0.5) reciprocally affected by EGCG treatment. Our study suggest that EGCG down-regulate the gene expressions of up stream signaling factors such as nemo like kinase with MAPK activity and PI3-Kinase, Ras GTPase and down stream factors such as cyclin D1, D2, H, T2, cdk6.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1398-1406
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• 2004

To develop the new type of salt-fermented seafoods, the salt-fermented oysters in olive oil (product SO) were manufactured, and food components and quality characteristics of product SO were examined. The optimum processing condition for product SO is as follows. The raw oyster with no shell was washed off with 3% saline solution. Then dewatered, and dipped in the brine-salting solution made up with saturated saline solution and oyster sauce (2 : 1 v/v) mixture added 1% sodium erythorbic acid and 0.2% polyphosphate. After salt-fermentation it ripened by brine salting at 5$\pm$1$^{\circ}C$ for 15 days. Then dried at 15$^{\circ}C$ for 4 hours with cool-air, and packed in No. 3B hexahedron type can. Finally, poured with olive oil and seamed it by double-seamer. The moisture, crude protein, crude ash and volatile basic nitrogen contents of the product SO were 61.6%, 12.0%, 16.3% and 34.3 mg/100 g, respectively. In taste-active components of the product SO, total amount of free amino acids is 2,335.4 mg/100 g and it has increased by 50% overall during salt-fermentation 15 day. Taurine, glutamic acid, proline, glycine, alanine, $\beta$-alanine and lysine were detected as principal free amino acids. The contents of inorganic ions were rich in Na and K ion, while the amounts of nucleotide and its related compounds and other bases except betaine were small. From the results of this research, the product SO had a superior organoleptic qualities compared with conventional oyster product, and could be reserved in good conditions for storage 90 days at room temperature.

• Food Science and Preservation
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• v.20 no.5
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• pp.643-649
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• 2013

The antioxidant activity and amino acid composition of various Cheonggukjang extracts, such as the water extract from Cheonggukjang (CWE), the alcohol extract from Cheonggukjang (CEE), the water extract from Cheonggukjang with black garlic (BWE) and the alcohol extract from Cheonggukjang with black garlic (BEE), were examined to investigate the effect of black garlic on the sensory quality and functional properties of Cheonggukjang. The total polyphenol contents of various extracts were 7.03 mg/100 g (BWE), 3.64 mg/100 g (CWE), 2.88 mg/100 g (BEE) and 0.81 mg/100 g (CEE). The radical scavenging activity of the DPPH radical was highest in BWE (91.83%), followed by BEE (37.35%), CWE (25.54%) and CEE (14.80%), in that order. The SOD-like activity was highest in BWE (20.20%), followed by BEE (9.22%), CWE (7.91%) and CEE (6.45%). The thiobarbituric acid reactive substances (TBARS) were highest in BWE (35.18%), followed by BEE (28.33%), CWE (17.40%) and CEE ((14.93%). The total amino acid content of Cheonggukjang (CC) was higher than that of Cheonggukjang with black garlic (CCWB), but the essential amino acid content of CCWB (43.18%) was higher than that of CC (42.27%). The 27 kinds of free amino acid were found in CC, but only 23 kinds were found in CCWB. The L-lysine content was highest (9.23%) in CC, and the L-phenylalanine content was highest (23.14%) in CCWB. The free amino acids (L-threonine, L-serine, L-sarcosine, L-proline, L-alanine, L-valine and D,L-${\beta}$-aminoisobutyric acid) were found in CC but not in CCWB. The ${\gamma}$-amino-n-butyric acid (GABA) was found in CCWB but not in CC. These results suggest that the addition of black garlic has beneficial effects on the functionality of Cheonggukjang without decreasing its sensory characteristics.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.282-290
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• 1997

Hepatocytes of Anguilla japonica have been prepared using a collagenase perfusion technique. The isolated cells attached efficiently to fibronectin-coated culture dishes and subsequently formed monolayers in serum-free medium. These cultures maintained in appropriate medium at least for 10 days with minimal cell loss. The effects of estradiol and pituitary hormones on vitellogenin (Vg) synthesis were examined in primary hepatocyte culture of the immature eels. In fish, as in other oviparous vertebrates, estrogen is a major inducer of Vg synthesis. However, $estradiol-17\beta(E_2)$ alone was insufficient to induce Vg synthesis in cultures of eel hepatocytes. Combination of $E_2$ with growth hormone (GH) and/or prolactin (PRL) markedly stimulated Vg synthesis. Even in cultures exposed to $E_2$ or precultured without hormones for 8 days, $E_2$ alone could not fully induce Vg synthesis. The synthesis of Vg was dramatically increased when hepatocytes were cultured in medium supplemented with $E_{2}+GH+PRL$ for 6 days. At this point, even though GH and/or PRL were eliminated from the medium, Vg synthesis was not influenced by these factors during culture of further 3 days. These results indicate that pituitary hormones, in particular GH and PRL, play important roles in the regulation of Vg synthesis in primary cultures of eel hepatocytes.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.370-379
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• 2002

The composition of extractive nitrogenous constituents in four species of commercial marine seasoned-dried products (SDP) and five species of seasoned-dried and roasted products (SDRP) were analyzed. The extractive nitrogen contents were $688{\sim}1,124$ and $756{\sim}1,099\;mg/100g$ in SDP and SDRP extracts. Contents of Free amino acids such as glutamic acid, taurine, arginine, proline, alanine, and histidine were high in all samples. The combined amino acid amounted to $662{\sim}2,248$ and $1,146{\sim}1,821\;mg/100g$ in SDP and SDRP, respectively, which corresponded to 34.5 and 42.5% of the total free amino acid level. ATP and related compounds were $3.69{\sim}7.37$ and $2.17{\sim}8.45\;{\mu}mol/g$ in SDP and SDRP, respectively. Five types of betaines were detected in both specimens although in small amounts. TMAO, TMA, creatine, and creatinine were detected in both samples, however they have same variation in each sample. There was no significant difference in the extractive nitrogenous constituents between SDP and SDRP except in moisture, salinity, and contents of glutamic acid and creatinin (p<0.01).