• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1048-1056
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• 2002

Quality of fresh ginger deteriorates rapidly during low temperature storage, and its storage life is short due to sprouting and microbial spoilage. The objectives of this research were to develop, using additives, a minced ginger product, which could maintain acceptable quality for over 30 days, and to investigate its quality changes during the cold storage. Storage stability of minced ginger product was investigated from the standpoint of the inhibition of brown discoloration, gas formation and liquid-solid separation. Fresh ginger was peeled and ground to produce minced ginger (control). Sodium bisulfite, L-cysteine, NaCl, sodium benzoate, modified starch, and/or xanthan gum were added to the control to minimize quality loss during storage, and to develop an optimum formula (A) of minced ginger. Samples were packed in Nylon/PE films, stored at $5^{\circ}C$, sampled at a 30-day interval, and subjected to quality evaluations. Changes in pH, surface color, gas formation, liquid-solid separation, contents of free amino acids, free sugars, organic acids, and fatty acids were determined. Gas formation was effectively inhibited in samples with sodium benzoate and/or NaCl. Samples with xanthan gum did not result in liquid-solid separation. L-Cysteine and sodium bisulfite were effective in controlling discoloration. pH decreased during storage in all samples, except sample A. Organic acid contents of all samples increased during storage, with lactic acid content showing the highest increase. Free amino acid content decreased with increasing storage time. Free sugar content of all samples decreased during storage. Sensory results showed sample A maintained acceptable quality until 90 days of storage. These results suggest that quality of minced ginger could be successfully maintained with the additions of selected additives for up to 90 days.

• Applied Biological Chemistry
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• v.47 no.1
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• pp.49-54
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• 2004

Biotransformation process using microorganisms was examined to improve the bioconversion rate for the production of sotolon from the raw material. First, the extraction condition was optimized with regard to solvent type and pretreatment conditions. Dichloromethane was selected as a suitable solvent for the extraction of sotolon and sotolon-related compounds. Second, various microorganisms such as lactic acid-producing bacteria, yeast and fungi were tested for the biotransformation. Among the tested microbes, Agaricus blazei showed the highest conversion rate. Additives including amino acids, salts, and organic acids were investigated to test their effects on bioconversion. When the solution was added by isoleucine, ${\alpha}-ketoglutaric\;acid$, ascorbate, and $FeSO_4$ and later incubated by culture broth containing the mycelium of Agaricus blazei, the sotolon content increased up to about 77 times as compared to that of the raw material.

• Journal of Sericultural and Entomological Science
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• v.41 no.2
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• pp.108-115
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• 1999

An improvement of methods in fibroin hydrolysates preparat significantly enlarges their applications to practical use. Acidic hydrolysis by hydrohloric acid is one of the methods for silk fibroin depolymeriza6tion. A low yield of final product and long time of the process are the demerits of this method. Possibility of preparation of water-soluble silk hydrolysates with more yield and less expenses is investigated in this study. Such possibility is occurred with the increasing tratment temperature and simultaneously decreasing treatment time, concentration of hydrochoric acid respectively, the concentration of sodium hydroxide used for neutraliza6tion of hydolysates after hydrolysis. Colour is decreased in this case and a small amount of activated, too. Protection of hydrolysates against precipitation after neutraliza6tion, and separation and during concentrating process is the other merit of this method. Creamy-coloured insoluble silk powder is the remainder of hydrolyzed fibroin. This is the only the immobiliza6tion of enzymes and other physiological active substances. Fine particles of this powder can be used as additives for artificial diets and cultural media, as well as raw materials for polymer membranes, etc.

• YAKHAK HOEJI
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• v.34 no.3
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• pp.215-218
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• 1990

An ion chromatographic method based on indirect photometric detection of UV transparent anions was developed. Separation of anion was accomplished on strong anion exchange column (Waters SAX) using UV detector at 254 nm. Among examined UV-active additives (Dns-H, Dns-glu, Dnsser, Dns-val), Dns-glu showed the highest sensitivity. Studies on the effects of the pH and ionic strength of eluent revealed that the increase of pH and ionic strength of the eluent decreased capacity factor. The best eluent for the separation of acetate, fluoride, chloride, nitrate and bromide was $1\;{\times}\;10^{-4}M$ Dns-glu in 5 mM phosphate buffer (pH 6.30). The detection limit of chloride ion was 2.1 ng in this condition.

• Computers and Concrete
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• v.29 no.4
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• pp.237-246
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• 2022

The concrete quality relies on general factors like preparation technique, uniformity of the compaction, amount and appropriateness of the additives. The current article investigates the impact of a well knows amino acid, L-arginine as an additive on water requirements, setting durations and characterization of various cement samples. Compressive strength tests of reference and L-arginine added cements at age of 2, 7 and 28 days were carried out according to TS-EN 196-1. Samples were blended by incorporating various amounts of L-arginine (25 ppm, 50 ppm and 75 ppm) in the cement water mixture which were tested with Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermo-gravimetric analysis (TG), scanning electron microscopy (SEM) and the energy-dispersive X-ray spectroscopy (EDS) on the 28th day. Results revealed that L-arginine does not affect the setting time, volume expansion of cement and water demands negatively; rather it imparts enhanced sustainability to the samples. It was determined that the highest value belonged to the 75L mortar with an increase of 2.6% compared to the reference sample when the compressive strengths of all mortars were compared on the 28th day. Besides, it has been observed that the development of calcium silicate hydrate or C-S-H gel, calcium hydroxide or CH and other hydrated products are associated with each other. L-arginine definitely has a contribution in the consumption of CH formed in the hydration process.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.31-32
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• 2005

Neoagaro-oligosaccharides are produced only by enzymatic degradation of agarose by ${\beta}-agarase.^{1)}$ Neoagaro-oligosaccharides inhibit the growth of bacteria, slow the rate of degradation of starch, are used as low-calorie additives to improve food quality, and have macrophage-stimulating activity. Furthermore, neoagarobiose is a rare reagent that has both moisturizing effect on skin and whitening effect on melanoma $cells.^{2)}$ An agar-degrading marine bacterium was isolated from the sea water at the northeast coast in Cheju island, Korea. The strain was gram negative, aerobic, and motile rod. The 16S rRNA of the strain had the closest match of 98% homology, with that from Agarivorans albus. On the basis of several phenotypic characters and a phylogenetic analysis, this strain was designated Agarivorans sp. JA-1. In solid agar plate, Agarivorans sp. JA-1 produced a diffusible agarase that caused agar softening around the colonies. Agarivorans sp. JA-1 was cultured for 36 hr in marine broth 2216 (Difco, USA) and the supernatant that containing an extracellular ${\beta}-agarase$ was prepared by centrifugation of culture media. The enzyme exhibited relatively strong activity at $40^{\circ}C$ and was stable up to $60^{\circ}C$. Using PCR primers derived from the ${\beta}-agarase$ gene of Vibrio sp., the gene encoding ${\beta}-agarase$ from Agarivorans sp. JA-1 was cloned and sequenced. The structural gene consists of 2931 bp encoding 976 amino acids with a predicted molecular weight of 107,360 Da. The deduced amino acid sequence showed 99% and 34% homology to $agaA^{2)}$ and $agaB^{2)}$ genes for ${\beta}-agarase$ from Vibrio sp., respectively. The expression plasmid for ${\beta}-agarase$ gene of Agarivorans sp. JA-1 is being constructed and the recombinant enzyme will be biochemically characterized.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.459-468
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• 1986

This study was attempted to process low-sodium salt fermented small shrimp as substitutes for traditional high-sodium salt fermented one which has widely been favored and consumed in Korea. Low-salt fermented small shrimp was prepared with $4\%$ sodium chloride and $4\%$ potassium chloride, and various additives such as $0.5\%$ lactic acid, $6\%$ sorbitol and $4\%$ ethylalcohol extract of red pepper as preservatives and flavor enhancers. And the changes of taste compounds, volatile compounds and fatty acid composition in low-salt fermented small shrimp were analyzed and compared with those of conventional $20\%$ sodium salt fermented one during the fermentation of 120 days at $25{\pm}3^{\circ}C$. The most favorable taste for fermented small shrimp were reached at 60 days of fermentation. Judging from sensory evaluation, little difference of taste was detected between the low-salt fermented small shrimp and high-sodium salt fermented one. The principal taste compounds in fermented small shrimp were free amino acids, and betaine and nucleotides and their related compounds played an assistant role. The major amino acids in fermented small shrimp were glutamic acid, leucine, proline, glycine, lysine and aspartic acid. The major fatty acids in fermented small shrimp samples were 16:0, 20:5, 22:6, 16:1 and 18:1, and unsaturated fatty acids decreased slightly while saturated fatty acids increased during fermentation. At 60 days of fermentation 8 kinds of volatile fatty acids (acetic acid, propionic acid, isobutyric acid, butyric acid, isovaleric acid, valeric acid, isocarproic acid, carproic acid), 6 kinds of carbonyl compounds (ethanal, propanal, 2-methylpropanal, 3-methylbutanal, pentanal, 2-methylpentanal), and 3 kinds of volatile amines (methylamine, trimethylamine, isopropylamine) were identified.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.3
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• pp.270-276
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• 2016

This study investigated the sensory characteristics (texture, odor, taste and color) of jerky produced from ground sea rainbow trout (SRT) Oncorhynchus mykiss frame muscle (FM). The hardness of the ground SRT-FM jerky was 453.9±91.0 g/cm², which was lower than that of commercial animal jerky (893.5±404.6 g/cm²) and commercial fish jerky (1,394.4±363.5 g/cm²). The difference in the hardness values of the ground SRT-FM jerky and commercial animal jerky was not significant. The volatile basic nitrogen content of the ground SRT-FM jerky was 48.3±1.6 mg/100 g, which was higher than that of commercial fish jerky (21.6±6.2 mg/100 g) and commercial animal jerky (18.2±6.3 mg/100 g). However, the fish odor of the ground SRT-FM jerky was masked by the presence of various additives. The hydrophilic and lipophilic browning indices of the ground SRT-FM jerky were higher than those of the commercial jerky. The total taste value of the ground SRT-FM jerky was 169.0, and the major amino acids were glutamic acid and aspartic acid. These results suggest that ground SRT-FM jerky would be acceptable to consumers.

• Journal of Sericultural and Entomological Science
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• v.51 no.1
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• pp.68-72
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• 2013

Fibroin and sericin are natural proteins obtained from cocoon and one of the spotlight materials for medical device. Medical device made of these proteins also has the advantage that this material is biodegradable in to amino acid. In this study, we prepared silk sponges using fibroin, sericin and additives. The characterizations of the silk sponges such as morphology, stability, and blood absorbency were observed. The structural stability of the silk sponge decreased significantly by increasing sericin contents. The effect on the concentrations of ethanol to induce crystallization was observed to be superior to 70% ethanol. Structural stability of silk sponges containing additives was very lower than those not containing additives. The blood absorbency of the silk sponges was found to be excellent, regardless of the composition of sericin and fibroin. The resilient power of these sponges was also very good, in spite of the repeated soaking and drying. Therefore, we expect that the silk sponges can be used medical supplies such as plastic implants and hemostatic cotton.

• Journal of Conservation Science
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• v.33 no.1
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• pp.51-59
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• 2017

Lacquer has been used as a natural paint or adhesive in Korea since 2nd century B.C. It has been found to have been used as an adhesive as mentioned in old records and as seen in excavated relics, It was also mixed with flour, animal glue, or fish glue to produce lacquer adhesives. Qualitative analysis and evaluation of the applicability of lacquer and additives was performed in this study. The results of EGA analysis for lacquer additives confirmed that the pyrolysis temperature of lacquer, glucose glue, and animal glue. On the basis of this result, raw lacquer sample was checked that pyrolysis product that originated from urushiol side chain (R group). Components originating from glucose and amino acid were detected in glutinous rice paste and animal glue samples. In this study, the optimum pyrolysis temperature for each lacquer and additive mixture was determined from basic qualitative analysis data. By performing the qualitative analysis of each mixture, the applicability of this technique for analyzing real relics was evaluated.