• Journal of Food Hygiene and Safety
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• v.23 no.1
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• pp.62-67
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• 2008

Inactivation of Salmonella Typhimurium and Listeria monocytogenenes in mandarin orange, Prunus mume (maesil), and kiwi juices was evaluated. A three-strain mixture of S. Typhimurium or L. monocytogenes was inoculated (7 log CFU/ml) into a commercial mandarin orange juice and maesil juice, and home-maid kiwi extract. The inactivation effect of Maesil juice was estimated by the addition into the other two fruit juices. All fruit juices had acidic pH, ranging from 2.8 to 3.5 and it was not variable during all experimental period, being at $4^{\circ}C$ for 14 days, The present study demonstrated that Maesil juice inactivated throughly L. monocytogenes within 7 days, while kiwi extract and mandarin orange juice archived 3.0-log inactivation and 1.0-log inactivation, respectively, until 14 days of storage. S. Typhimurium was completely reduced by Maesil juice and kiwi extract within 14 days, but mandarin orange juice showed only 1.4-log inactivation. The inactivation of L. monocytogenes and S. Typhimurium was increased by adding 10% maesil juice to both mandarin orange juice and kiwi extract.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.174-179
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• 2013

Three low-molecular compounds were isolated from methanol extracts of pear (Pyrus pyrifolia N. cv. Chuhwangbae) fruit peels using solvent fractionation, various types of column chromatogrphy (Diaion HP-20, Sephadex LH-20, and silica gel), and high performance liquid chromatography with an assay guided by 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity. The isolated compounds were identified as 2-carboxyl-4(1H)-quinolinone (kynurenic acid, 1) from butanol fraction, cis-p-coumaric acid (2) from ethyl acetate-acidic fraction, and vanillin (3) from the ethyl acetate-phenolic fraction, respectively. These isolated compounds were confirmed on the basis of the spectroscopic data of electrospray ionization mass spectrometry and nuclear magnetic resonance. This is the first time that compounds 1-3 were isolated and identified in pear.

• Journal of Applied Biological Chemistry
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• v.60 no.3
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• pp.257-263
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• 2017

A cellulolytic strain Y2 was isolated from soil obtained in the Canadian Alpine region. The isolate was identified as Paenibacillus sp. Y2 by 16S rRNA sequencing. When grown in LB medium supplemented with carboxymethyl-cellulose (CMC), CMCase production increased to 122.0% of that observed in LB without CMC. Culture supernatant was concentrated by ultrafiltration and 80% ammonium sulfate precipitates were separated by Hi-Trap Q and CHT-II chromatography. The purified enzyme (EG-PY2) showed a homogeneous single band and the molecular mass was estimated to be 38 kDa by SDS-PAGE. Optimum pH and temperature of the enzyme were 4.5 and $30^{\circ}C$, respectively. The half-life of enzyme activity at 50 was 140.7 min, but the enzyme was drastically inactivated within 5 min at $55^{\circ}C$. The enzyme was highly activated to 135.7 and 126.7% by 5.0 mM of $Cu^{2+}$ or $Mg^{2+}$ ions, respectively, and moderately activated by $Ba^{2+}$ and $Ca^{2+}$ ions, whereas it was inhibited to 76.8% by $Fe^{2+}$, and to ${\leq}50%$ by $Mn^{2+}$, $Co^{2+}$, $Zn^{2+}$, and EDTA. The enzyme was activated to 211.5% in the presence of 0.5 M of NaCl and greatly tolerant to 3.15M of NaCl. The enzyme showed 2.98 times higher ${\beta}$-glucanase activity than CMCase activity. Based on these results, it can be concluded that EG-PY2 is an acidophilic, cold-active, and halotolerant endoglucanase. The authors suggest it is considered to be useful for various industrial applications, such as, fruit juice clarification, acidic deinking processes, high-salt food processing, textile and pulp industries, and for biofuel production from seaweeds.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.176-181
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• 1980

As a part of experiments aimed to reduce the acidic taste of a soured fruit wine, a selected yeast strain was studied on its morphological and physiological properties as well as its fermentative characteristics of apple wine. The results obtained were as follows. 1. The selected yeast strain was identified as a strain of Schizosaccharomyces pombe. 2. The tolerance of the strain to metabisulfite in apple juice was stronger than that of wine yeast. 3. The growth rate of the strain was more rapid than those of wine yeast and Sake yeast when cultured in apple juice at $25^{\circ}C$, but it was decreased below the levels of others when cultured at $15^{\circ}C$. 4. The levels of ethanol production and acid reduction by the strain were high when the apple wine brewed at $25^{\circ}C$, while these were dropped significantly at $15^{\circ}C$.

• Food Science and Industry
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• v.49 no.4
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• pp.94-99
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• 2016

Development of synthetic vinegar has been focused on the acidic taste typically caused by acetic acid. Recently, consumer interest in fermented vinegars which contain a variety of valuable nutrients increased growth of the beverage industry. Vinegar beverages made of a variety of foreign fruits such as pineapple, grapefruit, and aloe are being commercialized to meet market needs from female consumers interested in beauty. However, commercialization of traditional fermented vinegars using regional products such as rice has not been successful yet compared to fruit vinegar beverages. Systematic research for development and commercialization of functional value-added traditional vinegars made of regional agricultural products should be performed. In this study, type and manufacturing methods of traditional vinegar were reviewed based on classic literatures.

• Food Science and Preservation
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• v.14 no.3
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• pp.315-322
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• 2007

The patulin producing capicity of Penicillium crustosum, an isolate from Korean apple, in various broth culture media, was investigated, and compared with patulin production by the standard strain P. griseofulvum(ATCC 46037). The maximal patulin production capacity of the P. griseofulvum ATCC 46037 was 2,029-2,829 ppm in 5-GYEP, SY and MEB broth media. The patulin-producing capacity of the isolated fungus(P. crustosum) attained 2,794 ppm in a 5-GYEP broth medium, but was only 324 and 11 ppm in SY and MEB media, respectively. There were no significant correlations between mycelial growth levels and patulin-producing ability in either P. crustosum or P. griseofulvum. The patulin production of P. griseofulvum was induced in the wide pH range of pH 3.0-11.0, while that of P. crustosum was induced in the acidic pH range pH 3.0-5.0. Patulin production levels were dependent on the carbon sources in the media and maximal patulin production by P. griseofulvum and P. crustosum was observed in media containing glycerol and fructose, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.6
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• pp.383-387
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• 2004

Effects of oyster shell powder as a liming material were investigated in an apple orchard. Soil texture of the apple orchard was silty clay loam (Upyeong series with 7% of slope) and topsoil pH was 5.6. Treatments of 1,590 kg oyster shell powder $ha^{-1}$ and calcium-magnesium carbonate as much as oyster shell powder were included in the experiment. With treatments of oyster shell powder and calcium-magnesium carbonate, the length, number and diameter of new branches and the diameter of main, secondary and side branches increased in comparison with control. With oyster shell powder application, soil pH increased from 5.6 to 6.8 at the harvest. In addition, it increased exchangeable Ca from 2.6 to $4.2cmol_c\;kg^{-1}$. But it didn't make any difference in chlorophyll, sugar and malic acid contents. The apple weight per fruit of oyster shell powder application was 9 g more than that of control. Apple yield was highest ($37,000kg\;ha^{-1}$) in the oyster shell powder treatment, and the yield increase was significantly different at 5% level LSD. We concluded that the oyster shell powder can be an alternative of lime and effective to restore soil nutrient balance in apple orchard soil.

• Journal of Mushroom
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• v.17 no.3
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• pp.99-106
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• 2019

To improve the productivity of shiitake mushroom (Lentinula edodes), seven different types of media for liquid spawn (denoted as "A" to "G") were prepared with 0.3% soybean meal and varying sugar and glucose concentrations. During 14 days of incubation, the pH of the liquid culture gradually acidified with increasing incubation period. Additionally, there was a significant, but not prominent, difference in the degree of acidification depending on the sugar to glucose ratio. Liquid spawn culture "G," which had the highest sugar content was the most acidic on the last day of incubation. Mycelium dry weight increased significantly with increasing incubation period, and there was no significant difference in mycelium dry weight irrespective of the sugar to glucose ratio even after 14 days of culture. The inoculation of liquid spawn in sawdust medium with an inoculation volume ${\geq}45mL$ and incubation period of 15 to 18 days were the optimal culture conditions. Productivity of fruit bodies in sawdust medium and mushrooms treated with liquid spawn was significantly higher compared to solid spawn treatment. The mushrooms treated with liquid spawn had better chewiness, and the free amino acid content, which is associated with savory taste, was higher in these mushrooms compared to those treated with solid spawn.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.409-413
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• 2004

We have studied quality changes of fully ripe fruit of Korean native pumpkin 'Yangsan' regarding the following parameters: pH, sugar content, weight, water content, contents of crude protein and amino acids during 60 days storage at room temperature. As the results, there was no changes in sugar contents according to the storage period, but pH was changing to a little acidic direction with slight decrease in weight and water content. Contents of total crude proteins and comprising amino acids were increased during the storage period. The main contents of amino acids of the Korean native pumpkin, Yangsan, were glutamic acid (15.5%), aspartic acid (10.1%), lysine (8.7%), valine (7.5%), leucine (7.1%) and alanine (6.6%), which were not highly influenced during storage period. Additionally we have investigated the content of free amino acids and color changes during processing of Yangsan under high temperature at $121^{\circ}C$ and high pressure at $1\;kg/cm^2$. In fully ripe fruits, a total of 29 kinds of free amino acids were detected including 8 kinds of essential amino acids (histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine and valine). More than 35% of total free amino acids were aspartic acid (20.3%) and asparagine (15.4%); ornithine, citrullin, and arginine, which are related to Ornithine cycle, were also detected in fully ripe fruits. But when treated with high temperature and high pressure, glutamic acid and arginine were decreased rapidly whereas ammnonium chloride was relatively increased. Moreover "b" value as yellow color indicator was decreased from 17.45 to 9.14 while treated for 60 minutes with high temperature and pressure, caused by the degradation of ${\beta}-carotene$ and other yellowish pigments in Yangsan.

• Journal of Korean Society of Forest Science
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• v.62 no.1
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• pp.24-42
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• 1983

To develop Ilex cornuta which grow naturally in the southwest seaside district as new ornamental tree, the author chose I. cornuta growing in the four natural communities and those cultivated in Kwangju city as a sample, and investigated its ecology, morphology and characteristics. The results obtained was summarized as follows; 1) The natural distribution of I. cornuta marks $35^{\circ}$43'N and $126^{\circ}$44'E in the southwestern part of Korea and $33^{\circ}$20'N and $126^{\circ}$15'E in Jejoo island. This area has the following necessary conditions for Ilex cornuta: the annual average temperature is above $12^{\circ}C$, the coldness index below $-12.7^{\circ}C$, annual average relative humidity 75-80%, and the number of snow-covering days is 20-25 days, situated within 20km of from coastline and within, 100m above sea level and mainly at the foot of the mountain facing the southeast. 2) The vegetation in I. cornuta community can be divided that upper layer is composed of Pinus thunbergii and P. densiflora, middle layer of Eurya japonica var. montana, Ilex cornuta and Vaccinium bracteatum, and the ground vegetation is composed of Carex lanceolata and Arundinella hirta var. ciliare. The community has high species diversity which indicates it is at the stage of development. Although I. cornuta is a species of the southern type of temperate zone where coniferous tree or broad leaved, evergreen trees grow together, it occasionally grows in the subtropical zone. 3) Parent rock is gneiss or rhyolite etc., and soil is acidic (about pH 4.5-5.0) and the content of available phosphorus is low. 4) At maturity, the height growth averaged $10.48{\pm}0.23cm$ a year and the diameter growth 0.43 cm a year, and the annual ring was not clear. Mean leaf-number was 11.34. There are a significant positive correlation between twig-elongation and leaf-number. 5) One-year-old seedling grows up to 10.66 cm (max. 18.2 cm, min. 4.0 cm) in shoot-height, with its leaf number 12.1 (max. 18, min), its basal diameter 2.24 mm (max. 4.0 mm, min. 1.0 mm) and shows rhythmical growth in high temperature period. There were significant positive correlations between stalk-height and leaf-number, between stalk-height and basal-diameter, and between number and basal diameter. 6) The flowering time ranged from the end of April to the beginning of May, and the flower has tetra-merouscorella and corymb of yellowish green. It has a bisexual flower and dioecism with a sexual ratio 1:1. 7) The fruit, after fertilization, grows 0.87 cm long (0.61-1.31 cm) and 0.8 cm wide (0.62-1.05 cm) by the beginning of May. Fruits begin to turn red and continue to ripen until the end of October or the beginning of November and remain unfading until the end of following May. With the partial change in color of dark-brown at the beginning of the June fruits begin to fall, bur some remain even after three years. 8) The seed acquision ratio is 24.7% by weight, and the number of grains per fruit averages 3.9 and the seed weight per liter is 114.2 gram, while the average weight of 1,000 seeds is 24.56 grams. 9) Seeds after complete removal of sarcocarp, were buried under ground in a fixed temperature and humidity and they began to develop root in October, a year later and germinated in the next April. Under sunlight or drought, however, the dormant state may be continued.