• Journal of the East Asian Society of Dietary Life
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• v.15 no.4
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• pp.437-443
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• 2005

Quality characteristic of Kipfel cookies with 0, 20, 40 and $60\%$ of freeze dried chitosan-chungkukjang(CC), which was fermented for 24 hours at $40^{\circ}C$ with steamed soybean added with $0.25\%$ of chitosan(MW 2,025 kDa) powder and inoculated $2\%$ of Bacillus lichenifomis, were investigated Bulk density was higher in the CC cookie, but there were no difference among the CC cookies. While hardness was decreased, brittleness and springiness were increased in the higher ratio of CC, but no significant difference was observed in cohesiveness and gumminess. According to increasing the CC ratio, L$\ast$ values and hue angle were decreased from 62.69 and 96.71 to 44.41 and 69.30, respectively. While a$\ast$ values were increased from -1.94 to 4.95, and no changes were observed in b$\ast$ values. Glucosamine content was $27.34 mg\%$ in the control cookie, $40{\~}93.75 mg\%$ in the CC cookies. Antioxidant activity of the CC cookies were higher than the control. The activity of the control cookie was decreased during storage, while it was maintained in CC cookies. There were no differences in the sour, sweet and savory taste. Off-flavor did not detected in the $0{\~}40\%$ CC cookies, but the chungkukjang odor was slightly detected in the $60\%$ CC cookie. The $20{\~}40\%$ CC cookies did not affect on native odor of Kipfel cookie. Color acceptability also did not affect by addition of CC $20{\~}40\%$ but it was lower in $60\%$ CC cookie. Overall acceptability was the best in the $20\%$ CC cookie.

• Macromolecular Research
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• v.16 no.1
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• pp.57-61
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• 2008

Chitosan is normally acylated and subsequently conjugated with drugs for biomedical applications. This study examined the relationship between the succinylation and gelation behaviors of glycol chitosan. Glycol chitosan was acylated with succinic anhydride under a wide variety of reaction conditions, such as different molar ratios of succinic anhydride to glucosamine, different methanol content in the reaction media, and different reaction temperatures. Among these reaction parameters, the methanol content in the solvent played an important role in determining the regioseletive succinylating site. N-succinylation and N-N cross-linking occurred regardless of the reaction conditions. However, O-succinylation was observed under specific conditions, i.e. a methanol content> 0.6 (v/v) and a reaction temperature> $25^{\circ}C$. O-succinylation accelerated the N-O cross-linking of glycol chitosan, and led to gelation. The N-succinylated glycol chitosans were water-soluble, whereas the N-and O-succinylated glycol chitosans fonned a gel. These physico-chemical structural differences in the succinylated glycol chitosans would definitely influence subsequent drug-conjugation reactions and consequently the drug loading and release kinetics.

• Molecules and Cells
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• v.19 no.3
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• pp.398-401
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• 2005

The bacterial enzyme UDP-N-acetylglucosamine enolpyruvyl transferase catalyzes the first committed step of peptidoglycan biosynthesis, i.e., transfer of enolpyruvate from phosphoenolpyruvate to UDP-N-acetyl-glucosamine. We have overexpressed the enzyme from Haemophilus influenzae in Escherichia coli and crystallized it in the apo-form, as well as in a complex with UDP-N-acetylglucosamine and fosfomycin using ammonium sulfate as the precipitant. X-ray diffraction data from a crystal of the apo-form were collected to $2.8{\AA}$ resolution at 293 K. The crystal quality was improved by co-crystallization with UDP-N-acetylglucosamine and fosfomycin. X-ray data to $2.2{\AA}$ have been collected at 100 K from a flash-frozen crystal of the complex. The complex crystals belong to the orthorhombic space group I222 (or $I2_12_12_1$) with unit-cell parameters of a = 63.7, b = 124.5, and $c=126.3{\AA}$. Assuming a monomer of the recombinant enzyme in the crystallographic asymmetric unit, the calculated Matthews parameter ($V_M$) is $2.71{\AA}^3Da^{-1}$ and solvent content is 54.6%.

• Journal of Microbiology and Biotechnology
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• v.6 no.6
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• pp.432-438
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• 1996

Native crystalline chitin was hydrolyzed in an agitated bead reaction system using crude chitinase excreted from Aspergillus fumigatus JC-19. The reaction was enhanced significantly, and the concentration and yield of reducing sugar after 48 hours were measured to be 35.42 g/I (w/v) and 0.64, respectively, around 1.86 times higher than those of the conventional system that was carried out without glass beads. The effect of reaction conditions, such as the amounts of chitin, chitinase and glass beads, and the size of glass bead, were examined. Ball milled chitin was also hydrolyzed in the agitated bead reaction system, the conversion yield and reaction rate of ball milled chitin for 24 hours increased up to 0.87 and 48.02 g/I, respectively. Chitinase showed relatively high stability in the agitated bead reaction system, particularly in the presence of enzyme stabilizer, $Ca^{++}$, which played a critical role in preventing the deactivation of chitinase by the physical impact of glass beads. The variations of the structural features of chitin during the reaction were followed by SEM and X-ray diffraction, and the enhanced hydrolysis reaction was caused by both the fragmentation of chitin particles and the destruction of the crystalline structure owing to the synergic effects of the attrition of glass beads and the hydrolytic action of chitinase.

• Korean Journal of Veterinary Service
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• v.31 no.2
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• pp.239-254
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• 2008

This study was conducted in order to get basic data on standards and specifications of health and functional foods. A total of 101 kinds of functional healths foods were examined during the period of January to December 2005. Among them, 89 kinds were local products and 12 kinds were imported products. Test items were 6 kinds of heavy metals (lead, cadmium, mercury, copper, zinc and manganese), 5 bacteria (common bacteria, coliform group, E coli, Bacillus cereus and Clostridium perfringens), and 6 preservatives (sorbic acid, benzoic acid, DHA, ethyl paraben, propyl paraben and butyl paraben). As a result of heavy metals, cadmium, was detected from the glucosamine products by 1.52ppm in average, mercury from cereal products by 0.004ppm in average, and lead from chlorella foods by 3.48ppm in average. Bacteria were identified from 3 cereal products, and amount of common bacteria were about $4.8{\times}105cfu/g$ in average. E Coli and Coliform group were isolated from 2 products and 4 products, respectively. All of those products were flour meal products. Any of 6 kinds of preservatives was not detected from all the products. It is thought that these test results will be available as basic data for enactment of relevant laws and regulations for production and control of safer and more hygienic foods in the future because the standards of the harmful heavy metals are not complete or available yet according to the Food Sanitation Law and the Functional Healths Foods Law.

• Journal of Ginseng Research
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• v.29 no.4
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• pp.206-214
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• 2005

The health function food law has been carried into effect from January 31, 2004 just after the proposal of 'a draft of a proposed law concerning the health function foods for the promotion of a nation health' on November 29, 2000 in Korea. After enforcement of health functional food law, there have been difficult market penetration with overall stagnancy of business activities and the current of health functional food within the country divided two groups. In standardized health functional foods the present condition, nutrition supplementary products (938 items) and red ginseng products (351 items) are prevalent and total 32 products are registered containing lactobacilli (297 items), glucosamine (295 items), ginseng (182 items), yeast(136 items) so on. In 2005, five products (products containing green tea extract, soybean protein, plant sterol, fructooligo sugar and Monascus sp. products are newly notified and raw material or component of total 21 products containing xylitol, teanin extract, sardine peptide are recognized as individual authorized health functional foods. Efficacies of ginseng are studied in many-sided researches but benefits of the ginseng in the health functional food law limited to 3 items (staminaresume, immune enhancement, nourishment robustness). To enlarge functionalities of ginseng it needs raw material and ingredient approval through data application to Korea Food and Drug Administration and this procedure acts as barrier of the functional food development in the ginseng industry. It is necessary to develop the authorized health functional foods for leading health functional food market in the future.

• Journal of the Korean Chemical Society
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• v.32 no.4
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• pp.377-384
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• 1988

Carotenoprotein from Salmo Salar eggs was purified and characterized by CM-cellulose, 50% $(NH_4)_2SO_4$, DEAE-cellulose and sephadex G-75 column. The chromoprotein had a spectrum with ${\lambda}_{max}$ 409, 540 and 580nm in p-buffer (pH 7.0) at initial step. Molecular weights by sephadex G-200 gel filtration were 50, 200 and 26,000 daltons. SDS-PAGE analysis showed a structure with four identical subunits (12,500 daltons). Its sample retained a small amount of carbohydrates and lipids. Amino acids were analyzed, and mannose, galactose and glucosamine also were identified. Carotenoid extacted with acetone was found to be astaxanthin ester by partition test, epoxy test, iodine test, allylic test, reduction, acetylation, uv/vis, ir and nmr datas. Stearate (47.9%) and palmitate (21.4%) were predominant fatty acids in the astaxanthin ester.

• Molecules and Cells
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• v.37 no.4
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• pp.322-329
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• 2014

N-acetylglucosamine kinase (GlcNAc kinase or NAGK; EC 2.7.1.59) is highly expressed and plays a critical role in the development of dendrites in brain neurons. In this study, the authors conducted structure-function analysis to verify the previously proposed 3D model structure of GlcNAc/ATP-bound NAGK. Three point NAGK mutants with different substrate binding capacities and reaction velocities were produced. Wild-type (WT) NAGK showed strong substrate preference for GlcNAc. Conversion of Cys143, which does not make direct hydrogen bonds with GlcNAc, to Ser (i.e., C143S) had the least affect on the enzymatic activity of NAGK. Conversion of Asn36, which plays a role in domain closure by making a hydrogen bond with GlcNAc, to Ala (i.e., N36A) mildly reduced NAGK enzyme activity. Conversion of Asp107, which makes hydrogen bonds with GlcNAc and would act as a proton acceptor during nucleophilic attack on the ${\gamma}$-phosphate of ATP, to Ala (i.e., D107A), caused a total loss in enzyme activity. The overexpression of EGFP-tagged WT or any of the mutant NAGKs in rat hippocampal neurons (DIV 5-9) increased dendritic architectural complexity. Finally, the overexpression of the small, but not of the large, domain of NAGK resulted in dendrite degeneration. Our data show the effect of structure on the functional aspects of NAGK, and in particular, that the small domain of NAGK, and not its NAGK kinase activity, plays a critical role in the upregulation of dendritogenesis.

• Journal of Microbiology and Biotechnology
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• v.7 no.2
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• pp.107-113
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• 1997

A strain producing a high amount of chitinase was isolated from soil, identified as Pseudomonas sp., and tentatively named Pseudomonas sp. YHS-A2. An extracellular chitinase of Pseudomonas sp. YHS-A2 was purified according to the procedure of ammonium sulfate saturation, affinity adsorption, Sephadex G-100 gel filtration and Phenyl-sepharose CL-4B hydrophobic interaction column chromatography. The molecular weight of the purified enzyme was estimated to be 55 kDa on SDS-PAGE was confirmed by active staining. Optimal pH and temperature of the enzyme are pH 7.0 and $50^{\circ}C$, respectively, and the enzyme is stable between pH 5.0 and 8.0 and below $50^{\circ}C$. The main products of colloidal chitin by the chitinase were N-acetyl-D-glucosamine and N,N'-diacetylchitobiose both of which were detected by HPLC analysis. The enzyme is supposed to be a random-type endochitinase which can degrade any position of ${\beta}$-l,4-linkages of chitin and chitooligosaccharides. The chitinase inhibited the growth of some phytopathogenic fungi, Fusarium oxysporum, Botrytis cineria, and Mucor rouxii and these antifungal effects were thought to be due to the characteristics of endochitinase.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.5
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• pp.251-254
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• 2006

Schizandrae Fructus has been used for controlling respiratory allergic or inflammatory diseases in folk medicine and their components, schizandrin, schizandrin-A and gomisin-A were reported to have diverse biological effects. In this study, we investigated whether schizandrin, schizandrin-A and gomisin-A affect adenosine triphosphate (ATP)-induced mucin secretion from cultured airway epithelial cells. Confluent primary hamster tracheal surface epithelial (HTSE) cells were metabolically radio labeled using $^{3}H-glucosamine$ for 24 h and chased for 30 min in the presence of varying concentrations of each agent to assess the effects on $^{3}H-mucin$ secretion. The results were as follows: 1) schizandrin significantly inhibited ATP-induced mucin secretion; 2) However, schizandrin-A and gomisin-A did not affect ATP-induced mucin secretion, significantly. We conclude that schizandrin can inhibit ATP-induced mucin secretion by directly acting on airway mucin-secreting cells. Therefore, schizandrin should further be investigated for the possible use as mucoregulators in the treatment of inflammatory airway diseases.