• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.252-261
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• 1983

Isopropyl alcohol extracted filefish protein concentrate (FPC) and NaOH hydrolyzed filefish protein isolate (FPI) were used for the investigation on the effect of processing conditions on the molecular distribution and functional properties. The molecular distribution of FPC on polyacrylamide gel showed a resemblance to that of fish muscle, but that of alkaline hydrolyzed FPI showed the severe degradation of protein. The content of several amino acids in FPI were lower than those of FPC. The pepsin digestibility of the FPC dried at high temperature was relatively high. FPC didn't exhibit a significant difference in nitrogen solubility at the pH range of 3.0-9.0, while FPI showed a wide difference with the pH change. FPI was more suspensible and rehydrated in water than FPC. Although the aeration capacity of FPI was very low, foam viscosity was higher than that of FPC. In contrast with aeration capacity, FPI presented higher emulsion capacity and lower emulsion viscosity than FPC. The size of fat globule in the emulsion of FPC was larger than that of FPI. In general, most functional properties decreased with the increment in drying temperature, except water holding capacity.

• Applied Biological Chemistry
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• v.30 no.2
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• pp.126-132
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• 1987

The usual sterilization methods such as fumigation and autoclaving of laboratory rodent diet was compared with a new irradiation treatment in the point of sterilization effect and physico-chemical quality. Under the treatments of $10{\sim}20\;kGy$ ${\gamma}-irradiation$ and autoclaving at $121^{\circ}C$ for 20 min, total microorganisms were eliminated but ethylene oxide fumigation was insufficient to destory them. Total amino acid content was reduced about 5% in 20 kGy radiation treatment compared with control, while in the ethylene oxide fumigation and the autoclaving, the reducing rate was markedly great as 15% and 20%, respectively. Total sugar and mineral contents were not significantly different among treatment among treatment groups. TBA values were increased in all treatments. The pH of irradiated group war stable in comparison with that of ethylene oxide. In the treatments of ethylene oxide and especially autoclaving, overall appearance was decreased to a great extent as a result of decreasing lightness and increasing redness.

• Polymer(Korea)
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• v.37 no.2
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• pp.127-134
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• 2013

The vascular endothelial cells are the inner layers of blood vessels. It regulates the function of blood vessels and proliferation of vascular smooth muscle cells. Poly(lactide-co-glycolic acid) (PLGA) is a biodegradable synthetic polymer with a well-controlled degradation rate and an acceptable mechanical strength. It can be easily fabricated into many shapes. Silk consists of 18 amino acids. It found important for attaching cells cultured in vitro, and maintaining cell functions. In this study, we fabricated silk/PLGA biomaterial hybrid films of 0, 10, 20, 40 and 80 wt% silk. We performed MTT, SEM, ELISA, and immunocytochemistry analyses. We confirmed the adhesion and the proliferation of HAECs on silk/PLGA according to the content of silk, and 40 wt% silk/PLGA hybrid films have superior adhesion and proliferation properties. These results demonstrate that silk/PLGA hybrid films provide suitable surfaces for HAECs, and there is the effect of silk on cell growth and proliferation.

• Food Science and Preservation
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• v.24 no.2
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• pp.221-229
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• 2017

The effect of sweet potato on the quality of Doenjang was investigated during fermentation. Viable cells of yeast decreased gradually after 4 weeks of fermentation, but those of aerobic bacteria increased in the late stage. Amylase activity of Doenjang was higher in the late stage of fermentation, while neutral protease maintained high activity during fermentation. Hunter L and b values of Doenjang decreased gradually during fermentation, while a value was increased. The pH of Doenjang decreased gradually until 10 weeks of fermentation, and the titratable acidity was low in the sweet potato added groups. The acid value was low in the Shinyulmi sweet potato added Doenjang. Water activity and oxidation-reduction potential of Doenjang decreased during fermentation. Reducing sugar of Doenjang decreased in the middle stage of fermentation, and it was low in sweet potato added groups. The alcohol content of Doenjang decreased after 2 weeks of fermentation. Amino and ammonia-type nitrogen of Doenjang increased during fermentation and reached the maximum after 10 and 12 weeks of fermentation, respectively. After 12 weeks fermentation, 8% of Shinyulmi sweet potato added Doenjang was more favorable taste, flavor and overall acceptability (p<0.05) than the control or the Yeonwhangmi sweet potato added groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1124-1129
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• 2005

Functional activities of low molecular weight substances purified from pepsin hydrolysates of four different seaweeds; Costaria costata, Enteromorpha prolifera, Grateloupia filicina and Porphyra tenera, were inves-tigated. Each pepsin hydrolysate of Costaria costata, Enteromorpha prolifera, and Grateloupia filicina resulted in three peptide peaks on Bio-Rad P2 gel chromatography pattern, while that of Porphyra tenera showed 2 peaks. Peak 1 of Porphyra tenera showed the highest antioxidative activity followed by peak 2 of Porphyra tenera and peak 2 of Costaria costata in order Peak 1 of Porphyra tenera showed the highest ACE inhibitory activity followed by peak 3 and peak 2 of Enteromorpha prolifera in order. Peak 1 and peak 2 of Porphyra tenera, and peak 2 of Enteromorpha prolifera showed the highest antityrosinase activity followed by peak 3 of Enteromorpha prolifera. Peak 1 of Enteromorpha prolifera showed the highest antitumor activity followed by peak 2 of Costaria costata, peak 3 of Enteromorpha prolifera, and peak 3 of Grateloupia filicina in order. Porphyra tenera showed the highest functional activities, which is thought to be due to its high protein content. Structure and amino acid sequence of low molecular weight peptide of Porphyra tenera should be analyzed in the further study.

• Food Science and Preservation
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• v.17 no.6
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• pp.826-834
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• 2010

We investigated the temperature changes during processing and quality characteristics of seven preparations of Byeok-hyang-ju described in ancient documents. During fermentation, treatments with intervals longer than 7 days to the second mashing kept temperatures below room temperature. The process with the shortest interval (2 days) between the second and third mashings maintained a preparation temperature above $28^{\circ}C$ for the longest period. As fermentation proceeded, the pH gradually decreased. Titratable acidities increased prior to the second mashing, and then decreased. Amino acid levels increased gradually during all fermentations except for that of method 5 (the lowest level of raw material addition). Ethanol content increased rapidly to the time of second mashing with all methods except method 2. This method featured a short interval between the first and second mashing. Upon sensory evaluation, the best overall acceptability was provided by method 3.

• Korean Journal of Food Science and Technology
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• v.19 no.5
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• pp.403-408
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• 1987

The effects of gamma irradiation on microbiological and chemical qualities of four kinds of poultry feeds were investigated. The viable counts of total bacteria in the samples were $10^5\;to\;10^6/g$. They were reduced by 2 to 3 log cycles after 3 to 5 kGy irradiation, and were completely eliminated with irradiation of 7 kGy. Coliforms and enteric pathogens were contaminated in high levels in all samples, ranging from $1.2{\times}10^4\;to\;1.7{\times}10^5/g\;and\;4.0{\times}10\;to\;2.6{\times}10^3/g$, respectively, They were sterilized by 3 to 5 kGy irradiation. Fungi, ranging from $10^{2}\;to\;10^4/g$, mainly osmophiles were identified as Aspergillus and Penicillium. They were eliminated to a undetectable level by 5 to 10 kGy irradiation. Six kinds of species, including Aspergillus flavus, were potential mycotoxin producers. Chemical components, such as proximate compositions, and mineral contents were not affected by the gamma irradiation. However, TBA values and amino acid content seemed to be affected by gamma irradiation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.139-147
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• 1991

The preservative effect of cellophane film packing on the quality of semi-salted and dried mackerel was studied. The product(P) of semi-salted and dried mackerel was prepared from raw mackerel by filleting, cleaning, soaking in 15%9v/w) salt solution for 30min, draining, packing with cellophane film (PT# 300, thickness:$20{\mu}{\textrm}{m}$) and drying for 4 hrs at $40^{\circ}C$ in hot air dryer. The product (C) was also prepared without cellophane film packing after draining. The product (C) and (P) were stored at $5.0{\pm}0.5^{\circ}C$. After processing and during storage, moisture content of product (P) was higher than that of product (C), but contents of VBN(volatile basic nitrogen), amino nitrogen and TMA of product (P) on dry basis were lower than those of product (C). Viable cell count, TBA value, peroxide value and decreasing rate of polyenoic acid of product (P) were also lower than those of product (C). In sensory evaluation, the shelf life of product (C) was about 9 days and that of product (P) was about 14 days. From the results of chemical and sensory evaluation, it was concluded that cellophane film packing was a good condition for preserving the quality of semi-salted and dried mackerel.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.612-624
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• 2022

A novel Gram-positive, motile, non-spore forming aerobic marine bacterium, designated 107-1^T was isolated from tidal mud collected in Gyehwa-do, South Korea. Cells of strain 107-1^T were short rod or coccoid, oxidase negative, catalase positive and grew at 10-40℃ (with optimum growth at 25-30℃). It utilized menaquinones MK-7 and 8 as its respiratory quinones and its major fatty acids were anteiso-C_15:0 (37.9%), iso-C_16:0 (14.9%), and iso-C_14:0 (10.8%). Phylogenetic analysis based on 16S rRNA gene sequences revealed a distinct clade containing strain 107-1^T and close species Planococcus ruber CW1^T(98.52% sequence similarity), P. faecalis KCTC 33580^T(97.67%), P. kocurii ATCC 43650T(97.48%), P. donghaensis DSM 22276T(97.47%), and P. halocryophilus DSM 24743T(97.37%). Strain 107-1^T contains one circular chromosome (3,513,248bp in length) with G+C content of 44.6 mol%. Estimated ranges for genome to genome distance, average nucleotide identity, and average amino acid identity comparing strain 107-1^T with close taxa were 20.3-34.8%, 77.9-86.9%, and 73.6-92.8%, respectively. Based on polyphasic analysis, strain 107-1^T represents a novel species belonging to the genus Planococcus.

• Clean Technology
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• v.16 no.2
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• pp.117-123
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• 2010

In this study, we propose two methods able to recover different type of gold from gold-cyanide solutions: biosorption and desorption process for mono-valent gold recovery and biosorption and incineration process for zero-valent gold recovery. The waste bacterial biomass of Corynebacterium glutamicum generated from amino acid fermentation industry was used as a biosorbent. The pH edge experiments indicated that the optimal pH range was pH 2 - 3. From isothermal experiment and its fitting with Langmuir equation, the maximum uptake capacity of Au(I) at pH 2.5 were determined to be 35.15 mg/g. Kinetic tests evidenced that the process is very fast so that biosorption equilibrium was completed within the 60 min. To recover Au(I), the gold ions were able to be successfully eluted from the Au-loaded biosorbent by changing the pH to pH 7 and the desorption efficiency was 91%. This indicates that the combined process of biosorption and desorption would be effective for the recovery of Au(I). In order to recover zero-valent gold, the Au-loaded biosorbents were incinerated. The content of zero-valent gold in the incineration ash was as high as 85%. Therefore, we claim on the basis of the results that two suggested combined processes could be useful to recover gold from cyanide solutions and chosen according to the type of gold to be recovered.