• 한국생물공학회:학술대회논문집
• /
• 2000.11a
• /
• pp.45-46
• /
• 2000

After cell removal from fermentation broth the supernatant containing poly (${\gamma}-glutamic acid$) (${\gamma}-PGA$) was concentrated by ultrafiltration in order to reduce the amount of organic solvents such as methanol, ethanol, propanol required for the recover of ${\gamma}-PGA$ with precipitation. The concentration and volume reduction of cell-free solution by ultrafiltration could reduce 3 times the amount of ethanol for the recover of ${\gamma}-PGA$ from cell-free fermentation broth.

• YAKHAK HOEJI
• /
• v.5 no.1
• /
• pp.1-2
• /
• 1960

Six kinds of free amino acids, leucine, methionine, threonine, lysine, histidine and aspartic acid were found by using partition paper chromatography from water extract of deer horn which is widely used as tonic drug. The results shows that deer horn does not contain any specific free amino acid.

• The Korean Journal of Community Living Science
• /
• v.15 no.3
• /
• pp.15-20
• /
• 2004

The purpose of this study was to evaluate the sensory characteristics and investigate the nutrients composition of sauce made with rock lobster shells or heads. Rock lobster head sauce(LHS) turned out to have better appearance, color, taste, flavor, texture and viscosity than rock lobster shell sauce(LSS). The crude protein content was 1.95% in LHS and 1.56% in LSS, and the crude lipid content was 1.60% in LHS and 2.27% in LSS. The major free amino acids of LHS were urea, a-aminoadipic acid, L-alanine, taurine, and those of LSS were urea, $\alpha$-aminoadipic acid, $nu$- and DL-$\beta$-aminobutyric acid. The major free fatty acids of both samples were palmitoleic acid and oleic acid, with a high quanitity of palmitoleic acid in LHS, and a significant amount of linoleic acid in LSS. The major minerals in rock lobster sauce were potassium and sodium.

• KSBB Journal
• /
• v.30 no.2
• /
• pp.91-95
• /
• 2015

Production of biodiesel from microalgae is dependent on the microalgal lipid content and free fatty acid composition. Both lipid and free fatty acid are regulated by nutrient sources. In this study, newly developed mutant Chlamydomonas reinhardtii with higher lipid content was investigated for the effect of nutrient limitation. Nitrogen $NO_3{^{-}}$ and phosphate $PO_4{^{3-}}$ were limited for nutrient starvation during the cultivation. Under nutrient starvation, total lipid content level was increased to 27~33% and C16:0 fatty acid content constituted over 31~43% of total fatty acid. Interestingly, we also found that the expression of fatty acid desaturase (FAD7) was decreased when nutrients were starved.

• Journal of the East Asian Society of Dietary Life
• /
• v.10 no.1
• /
• pp.37-41
• /
• 2000

Physiocheical properties and chemical compositions of two plums(Oishiwase, Formosa ) produced in Kimcheon area were investigated . Chemical compositions of two plum cultivars were similar except nitrogen free extract(NFE) . NFE value of Formosa was higher than Oishiwase . Alcohol insoluble substance content, total soluble pectin, total sugar content and total organic acid content of Oishiwase were 2.08%, 14.16%, 5.07% and 949.16mg%, respectively. In case of Formosa cultivar, those were 50%, 15.42%, 5.91% and 985.91mg%, respectively. Fructose content among free sugars of two plum cultivars range from 3.97-3.45% and the other were glucose, sucrose and inositol, 1.83-1.53%, 0.08-0.05% and 0.04-0.03%, respectively. Malic acid content was 35-373mg% and others were levulinic acid, lactic acid, citric acid, succinic acid and fumaric acid in the decreasing order.

• Food Science and Biotechnology
• /
• v.15 no.3
• /
• pp.404-408
• /
• 2006

Feasibility of surface plasmon resonance (SPR) method to evaluate soybean frying oil quality was evaluated. Free fatty acid value, p-anisidine value, conjugated dienoic acid content, conjugated trienoic acid content, peroxide value, iodine value, total polar compound (TPC), ratio of unsaturated fatty acid to saturated fatty acid, refractive index, dielectric constant, smoking point, and L, a, and b of Hunter color system were selected as parameters related to conventional evaluation of soybean frying oil quality. SPR scale mapped with conventional quality parameters well described free fatty acid value, conjugated dienoic acid content, dielectric constant, TPC, and b of Hunter color system, as shown by correlation and linear regression analyses.

• Journal of the Korean Society of Food Culture
• /
• v.17 no.3
• /
• pp.267-274
• /
• 2002

The quality characteristics of traditional Kyungsangdo Myungtae (Alaska pollack) sikhae including optimal composition of the product were investigated. In the sensory evaluation, the Myungtae sikhae made from Gampo accepted to be best for traditional Kyungsangdo Myungtae sikhae and it is called standard sikhae. The standard sikhae was prepared as follows: dried-Myungtae 200g, cooked rice 230g, red pepper 92g, garlic 112g, ginger 100g, radish 1.6kg, salt 20g, and malt meal 65g. The Myungtae sikhae made from Gampo showed higher values in total sugar, free reducing sugar, and nitrogen compounds than the Myungtae sikhae made from another locations. The sugar of standard sikhae consisted of four kinds including glucose. And, the contents of free amino acid was increased in the order of glutamic acid, alanine, and methionine. The composition of free amino acid in Myungtae sikhae contained 17 kinds, and the contents was increased in order of glutamic acid, aspartic acid, and proline. The organic acid of standard Myungtae sikhae consisted of 7 kinds including lactic acid during fermentation. The contents of citric acid, succinic acid, and lactic acid gradually increased during fermentation, and especially, increasing of lactic acid remarkably increased than the different organic acid.

• Proceedings of the SCSK Conference
• /
• 2003.09a
• /
• pp.719-732
• /
• 2003

A kojic acid derivative, kojic acid 7-O-$\beta$-D-tetraacetylglucopyranoside(KTG) was synthesized. Regio-and stereo-selective glycosylation at 7-postion in kojic acid with $\beta$-D-pentaacetylglucose was achieved with high yield(80％) by the use of Lewis acid and organic base in nonpolar solvent. KTG was hydrolyzed in methanol by the aid of sodium methoxide to give kojic acid 7-O-$\beta$-D-glucopyranoside(KGP). KGP is freely soluble in water and soluble in methanol and ethanol. Its structure was comfirmed by $^1$H-NMR and $^{13}$ C-NMR. Tyrosinase activity inhibition of KGP was measured with mushroom tyrosinase compared with ascorbic acid, kojic acid and arbutin. KGP showed higher tyrosinase inhibition activity($IC_{50}$/=33.3 $\mu\textrm{g}$/ml) than ascorbic acid(63.2 $\mu\textrm{g}$/ml) and arbutin(91.8 $\mu\textrm{g}$/ml) but lower inhibition activity than kojic acid(8.3 $\mu\textrm{g}$/ml). To test free-radical scavenging activity, we used 1, 1-diphenyl-2-picrylhydrazyl(DPPH) as a free-radical source. Free-radical scavenging activity of KGP was very low($SC_{50}$/>1000 $\mu\textrm{g}$/ml) compared with ascorbic acid($SC_{50}$/=2.68 $\mu\textrm{g}$/ml) and arbutin($SC_{50}$/=180$\mu\textrm{g}$/ml). Melanin formation inhibition of KGP was measured in B16 melanoma, compared with kojic acid, arbutin and Vitamin C. Inhibition activity of KGP for melanin formation was not found within test concentrations.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.10 no.1
• /
• pp.1-16
• /
• 1981

Fermented trepang entrails, Stichopus Japonicus, is widely used and occupied an important position in foods of this country. But little study on its taste compounds has been reported. This study was attempted to establish the basic data for evaluating taste compounds of fermented trepang entrails. Changes of free amino acids, free sugars, nucleotides and their related compounds as taste compounds during the fermentation of trepang entrails were analyzed by amino acid autoanalyzer and high speed liquid chromatography. Glutamic acid, alanine, glycine and proline were dominant amino acid in the fresh extracts, having 32.3%, 16.4%, 12.0% and 10.5% of the total free amino acid content, respectively. The content of leucine, valine, phenylalanine, isoleucine, methionine and tyrosine were low. The free amino acid were not changed in composition but changed in amounts during the fermentation of trepang entrails. Glutamic acid, alanine, glycine, proline, lysine, arginine and leucine were abundant in both fresh sample and fermented products. Free sugars in fermented trepang entrails, the results showed that galactose(933.7-988.0 mg%) was dominant and the content of arabinose, xylose were 78.7, 55.2-771mg% on moisture and salt free base respectively but glucose was detected in trace amount. Nucleotides and their related compounds were increased during the fermentation and hypoxanthine(47.1-$62.5{\mu}mole/g$, on moisture and salt free base) were dominant, IMP was abundant in fermented trepang entrails. TMA was increased while TMAO was decreased during the fermentation. The content of TMAO nitrogen in fermented trepang entrails was 30.0mg% on moisture and salt free base. The content of betine was increased during the fermentation and was ranged from 734.2 to 934.2mg% on moisture and salt free base. It is believed that such amino acids as glutamic acid, alanine, glycine, lysine, proline, arginine, leucine, such free sugars as galactose, arabinose, xylose, glucose, such nucleotides and their related compounds as IMP, hypoxanthine play an important role as taste compounds in fermented trepang entrails.

• Korean Journal of Food Science and Technology
• /
• v.45 no.3
• /
• pp.350-355
• /
• 2013

The quality of fermented dropwort extract (FDE) and fermented dropwort vinegar (FDV) was assessed for free sugar, organic acid and free and total amino acid content. Major organic acids were lactic acid in FDE and acetic acid in FDV. Free sugars in FDE were fructose and glucose, and those in FDV were fructose, sucrose, and maltose. Aspartic acid was the major free amino acid in both FDE and FDV. Additionally, the main free amino acids in FDE were alanine and ${\gamma}$-amino-n-butyric acid (GABA), while those in FDV were arginine and valine. Moreover, to investigate the protective effects of FDE and FDV against oxidative stress induced by t-BHP and $H_2O_2$, C6 cells were treated with FDE or FDV prior to inducing the oxidative damage. FDE and FDV inhibited cell death significantly in a dose-dependent manner. These data imply that FDE and FDV may be effective in neuronal cell protection against oxidative damage.