• Journal of Mushroom
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• v.10 no.4
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• pp.224-235
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• 2012

Quality change of winter mushroom were investigated during storage and distribution phase as influenced by storage temperature. According to storage period and temperature, amino acids, were analysed and quantified with the mushroom fruiting bodies using HPLC and morphological characteristics were investigated. Characteristic changes of winter mushroom fruiting bodies were described as follows during storage according to the storage temperature. Looking at the results of the analyzed amino acid contents, temperature between $-1^{\circ}C$ and $4^{\circ}C$ was optimal condition for the storage. At $4^{\circ}C$, the chemical composition tended to be maintained. On the other hand, the results indicate the rapid loss of nutrition at $-1^{\circ}C$ within 7 days of storage. Exceptionally, proline was shown to be increased. Brown line mushroom had a larger loss than white line mushroom. Based on this result, brown line mushroom have shown significant differences among varieties. Therefore, winter mushroom should be stored at $4^{\circ}C$ to minimize nutrient loss and to maintain freshness and mushrooms should be consumed within 14 days after harvest.

• Korean Journal of Microbiology
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• v.40 no.4
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• pp.313-319
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• 2004

The distribution and characteristics of acidotolerant heterotrophic and naphthalene-degrading bacteria were investigated in two forest areas, one near Ulsan petrochemical industrial complex (Sunam) and the other in countryside (Daeam). Average values of soil pH at Sunam and Daeam were 3.8 and 4.6, respectively. When het­erotrophic and naphthalene-degrading bacteria were enumerated by most probable number (MPN) procedures at Sunam, the median values of heterotrophs growing at pH 7.0 and pH 4.0 were $5.3{\times}10^7\;and\;3.3{times}10^7$ MPN/g, whereas those of naphthalene-degraders were $5.6{\times}10^4\;and\;4.0{times}10^5$ MPN/g, respectively. While the medians of heterotrophs at Daeam were larger than those at Sunam, the concentrations of naphthalene-degraders were higher at Sunam compared to those at Daeam. From the MPN tubes and enrichment cultures, we obtained 17 isolates of naphthalene-degraders which were identified as Sphingomonas paucimobilis, Brevundimonas vesic­ularis, Burkholderia cepacia, Ralstonia pickettii, Pseudomanas fluorescens, and Chryseomonas luteola. Among them, 6 isolates showed higher naphthalene-degrading activity on minimal media of pH 4 compared to pH 7, whereas the extent of growth was not greater at pH 4 than at pH 7 when they were inoculated on nutrient-rich media. It is plausible that the pH may affect naphthalene-degrading activity of the isolates by changing fatty acid composition of bacterial membrane.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.4
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• pp.283-289
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• 2017

The present study was carried out to explore the potential effect of shading degrees on yields and nutritive values of forage in forest-grassland. This experiment was conducted this study under different natural shading at National Institute of Animal Science, Cheonan province in Korea, for 2 years (from 2015 to 2016). This experiment was consisted of four different shading degrees, such as full sunlight (control, 10% below), 25% of shading, 35% of shading, 50% of shading. Pasture species used in this study were orchardgrass 'Kodiwin', perenial ryegrass 'Linn', tall fescue 'Purumi', kentuky bluegrass 'Kenblue', and white clover 'Ladino'. Botanical composition of orchardgrass was higher than that of perenial ryegrass, tall fescue and kentuky bluegrass. Dry matter (DM) yields of forage decreased as increasing shading degrees. DM yields of forage significantly decreased as increasing shading degrees and lots of cutting times under increasing shading degrees decreased DM yields of forage. The content of crude protein increased as increasing shading degrees and the contents of acid detergent fiber (ADF), neutral detergent fiber (NDF), the activity of total digestible nutrient (TDN) and in-vitro digestibility (IVD), and relative feed value (RFV) were similar in control and different shading. This study suggests that orchardgrass is major component for forest-grassland and establishment of orchardgrass can be improved by increasing shading degrees.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.422-427
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• 2013

The physicochemical properties of raw and black doraji were examined with the goal of increasing the utilization of doraji. Raw and Black doraji contained similar amounts of crude ash, crude fat, and crude protein, but raw doraji had higher level of fiber. Arginine was the major free amino acid in both types of doraji. Free sugar and organic acid contents of doraji increased after steaming heat treatment. Potassium was a prominent mineral in both raw and black doraji, constituting 85% of total minerals. Black doraji contained almost twice as much crude saponin as did raw doraji. Black doraji showed lower values of L (lightness), a (redness), and b (yellowness). The hardness and chewiness of raw doraji were higher than those of black doraji. Black dorai showed a higher amount and extraction rate of saponin, even though nutrient value of doraji slightly decreased after steaming heat treatment. Therefore, black doraji can be a valuable ingredient in functional foods.

• Journal of Life Science
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• v.7 no.1
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• pp.30-38
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• 1997

For screening thermostable $\alpha$-amylase from thermophiles, various samples from extreme environments such as hot spring and sewage near them, and compoat, wereexamined microbial growth in enrichment culture medium at 55$\circ$C on the assumption that enzymes from thermophiles are inevitable thermostable. One strain showing higher $\alpha$-amylase activity was pure cultured and designated as Bacillus sp. TR-25 from the results of morphological, cultural and physiological characteristics. The most important carbon sourses for the enzyme production were soluble starch, dextrin, potato starch and corn starch. Glucose and fructose had a catabolite repression on the enzyme production. The good nitrogen sources for the enzyme production were yeat extract, nutrient broth, tryptone, corn steep liquor and ammonium sulfate. The enzyme production was accelerated by addition of CaCl$_{2}$. $\cdot $ H$_{2}$O. The optimal medium composition for the enzyme production was soluble starch 2.0%, yeast extract 0.55, CaCl$_{2}$ $\cdot $ 2H$_{2}$O 0.015, Tween 80 0.001%, pH8.0, respectively. In jar fermenter culture, this strain shows a rapid growth and required cheaper carbon and nitrogen source. These properties are very useful to fermentation industry. The $\alpha$-amylase of this strain demonstrated a maximum activity at 80$\circ$C, pH 5.0, respectively. And calcium ion did not improve thermostability of the enzyme. At 10$0^{\circ}C$, this enzyme has 235 of relative activity. Transformation was carried out by thermophilic Bacillus sp. TR-25 genomic DNA. As a result, the transformant has increased thermostable $\alpha$-amylase activity.

• Journal of Life Science
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• v.27 no.10
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• pp.1185-1190
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• 2017

Insects are gaining recognition as an alternative source of protein. As a result, more and more domestic farms have begun mass rearing of edible insects. In order to produce high quality insects, studies on the development of safe and nutritious feed sources are needed. Given the cost of rearing insects, agricultural and industrial by-products are good sources for feed. The efficient utilization of these by-products can help in reducing the cost of production and preventing environmental pollution. In the current study, Citrus unshiu peel (CP), soybean curd cake (SCC), soybean oil meal (SOM), and brewers dried grain (BDG) were investigated for their effects on larval growth and development of Protaetia brevitarsis. Interestingly, the feed with 10% SCC increased larval weight by 3.5 times. For the larval period, the group of 10% SCC was significantly shorter than the control. Furthermore, minerals such as Zn, Ca, K, Mg, Na, and P were recorded to be high in 10% SCC. A total of 17 amino acids were present in 10% SCC, of which tyrosine and arginine were predominant. The heavy metal contents were very small amounts or not detected in any of the investigated groups. These findings provided a scientific basis for the utilization of soybean curd cake as a nutritional feed source to promote larval growth and produce quality insects.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.742-746
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• 2000

Quality improvements of soybean sprouts on DSSE(Defatted Sesame Seed Extracts)-treated cultivation were determined in terms of growth rate, nutrient compositions value and the total bacteria. The length, diameter and weight of treated soybean sprouts were increased by 6.2%, 10.0% and 9.1%, respectively, compared with control. The contents of moisture, crude ash, crude fat of the treated soybean sprouts were similar to the control soybean sprouts, whereas crude protein content of the treated sprouts was 17% higher than the control. Both soybean sprouts contained 17 amino acids but the treated sprouts contained the higher contents of glutamic acid, threonine, methionine, tyrosine and valine. Little difference in fatty acid composition was noted between the two soybean sprout samples. Vitamin C contents of the treated soybean sprouts were 18.2 mg%, which corresponds to about 50% more vitamin C than the control. The treated soybean sprouts contained higher contents in minerals such as K, P and Ca than those of the control. The total bacteria of soybean sprouts in the control soybean sprouts increased rapidly after 2-day storage, but treated soybean sprouts increased immediately after 4-day storage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.4
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• pp.237-247
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• 1991

To characterize the community structure and spatial distribution of phytoplankton, observations on seawater temperature, salinity, nutrients, primary productivity and abundance and species composition of phytoplankton were made in the polar front region and its neighborhood off the east coast of Korea in summer 1990. Among the 96 taxa identified, Rhizosolenia setigera and Thalassionema nitzschioides were the most dominant species. The assemblage at the surface and 50 m depth was quite different in the northern inshore part of the study area but similar in the southern and offshore part. Principal component analysis by the species abundance showed that the phytoplankton consisted of the communities representing the surface of the northern inshore part with the neritic-warm dinoflagellates, the Northern Korean Cold Water with the cold water diatoms and the southern and offshore part, which seems to represent the Eastern Korean Warm Water, with the warm water diatoms. At the frontal region, diatoms were mixed with warm and cold water species. Primary productivity and phytoplankton standing crops were higher at the front than the neighboring waters. Nutrients were markedly high at the Northern Korean Cold Water. Horizontal advection of the Northern Korean Cold Water accompanied by nutrient supply seems to contribute to the high phytoplankton biomass at the front.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.957-966
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• 2017

Objective: To understand the dynamic structure, function, and influence on nutrient metabolism in hosts, it was crucial to assess the genetic potential of gut microbial community in yaks of different ages. Methods: The denaturing gradient gel electrophoresis (DGGE) profiles and Illumina-based metagenomic sequencing on colon contents of 15 semi-domestic yaks were investigated. Unweighted pairwise grouping method with mathematical averages (UPGMA) clustering and principal component analysis (PCA) were used to analyze the DGGE fingerprint. The Illumina sequences were assembled, predicted to genes and functionally annotated, and then classified by querying protein sequences of the genes against the Kyoto encyclopedia of genes and genomes (KEGG) database. Results: Metagenomic sequencing showed that more than 85% of ribosomal RNA (rRNA) gene sequences belonged to the phylum Firmicutes and Bacteroidetes, indicating that the family Ruminococcaceae (46.5%), Rikenellaceae (11.3%), Lachnospiraceae (10.0%), and Bacteroidaceae (6.3%) were dominant gut microbes. Over 50% of non-rRNA gene sequences represented the metabolic pathways of amino acids (14.4%), proteins (12.3%), sugars (11.9%), nucleotides (6.8%), lipids (1.7%), xenobiotics (1.4%), coenzymes, and vitamins (3.6%). Gene functional classification showed that most of enzyme-coding genes were related to cellulose digestion and amino acids metabolic pathways. Conclusion: Yaks' age had a substantial effect on gut microbial composition. Comparative metagenomics of gut microbiota in 0.5-, 1.5-, and 2.5-year-old yaks revealed that the abundance of the class Clostridia, Bacteroidia, and Lentisphaeria, as well as the phylum Firmicutes, Bacteroidetes, Lentisphaerae, Tenericutes, and Cyanobacteria, varied more greatly during yaks' growth, especially in young animals (0.5 and 1.5 years old). Gut microbes, including Bacteroides, Clostridium, and Lentisphaeria, make a contribution to the energy metabolism and synthesis of amino acid, which are essential to the normal growth of yaks.

• The Korean Journal of Malacology
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• v.20 no.1
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• pp.55-63
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• 2004

Gonadosomatic index, condition index and reproductive cycle with the gonadal development of the female Octopus ocellatus were investigated by histological observations and morphometric data, from January to December, 2000. And changes in biochemical components of the ovary and the trunk tissues including the digestive organ associated with gonadal development were studied by biochemical analysis from January to October, 2001. The specimens were collected at the coastal waters of Buan, Jeollabuk-do, Korea, from January 2000 to October 2001. O. ocellatus is a dioecious organism. The gonad of O. ocellatus locates medially in posterior region of the body. Morphology of the ovary shows round and oval in shape, the average diameter and external colour of ripe ovary was 32 mm and semitransparent light brown in colour. As the ovary was getting mature, transparent elongated eggs covered with chorion were present in the ovarian cavity. Monthly changes in the gonadosomatic index (GSI) showed a similar pattern with those of the condition index. The GSI and condition index began to increase in March and reached the maximum in April. And then, their values decreased from May and reached the minimum in September. Reproductive cycle of O. ocellatus can be categorized into five successive stages: early developing stage (September to December), late developing stage (November to March), ripe stage (March to May), partially spawned stage (April to June), and degenerative/resting stage (June to October). Follicle cells attached to an oocyte were involved in vitellogenesis in the cytoplasm of the vitellogeneic oocyte and formation of chorion (secondary egg membrane) of the ovarian eggs. Spawning occurred between April and June. The spawning period was once a year and the peak took place between May and June. This species belongs to semelparity. According to changes in biochemical contents of the ovary and the digestive organ, monthly variations of moisture, total protein, total lipid and glycogen contents (%) in the ovary showed a negative correlationship with those of the trunk tissues including the digestive organ. Accordingly, it is assumed that the ovary only may be received nutrient supply (total lipid content) for gonadal development from the trunk tissues including the digestive organ (r = -0.55, p < 0.05).