• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.6
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• pp.787-794
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• 2009

In this study, a new method for extending storage-life and palatability of Betula platyphylla sap by applying lactic acid bacteria fermentation was developed. The fluids of saps were filtered through 0.22 ${\mu}m$ membrane filter and each fermented by 8 different lactic acid bacteria which are Lactobacillus acidophilus, Lactobacillus brevis, Leuconostoc mesenteroides, Leuconostoc lactis, Lactococcus lactis, Pediocossus pentosaceus, Pediococcus dextrinicus, Streptococcus thermophilus. All the tested lactic acid bacteria except P. dextrinicus grew fast up to $10^6{\sim}10^7cfu/mL$ levels and lowered pH down to about pH 4 levels in 48 hours in both saps. The produced organic acids and lowered pH level inhibited the growth of spoilage microorganisms almost completely for 2 weeks during storage at room temperature. Addition of xylitol in the saps before fermentation accelerated the growth of lactic acid bacteria and increased the sweetness and overall taste of final product. The filtration process did not affect the mineral compositions of Betula platyphylla saps. Also the compositions and amounts of minerals showed very minor differences before and after fermentation in Betula platyphylla saps inoculated with L. acidophilus. By applying lactic acid fermentation to extend storage-life of tree saps instead of heat treatment, it was possible to keep natural minerals in active forms without any modifications.

• Current Research on Agriculture and Life Sciences
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• v.32 no.3
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• pp.111-117
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• 2014

Phytophthora blight caused by Phytophthora capsici Leonian is a dangerous disease threatening pepper growers worldwide. The efficacy of chemical control is generally low as the pathogen is soil-borne and rapidly spread by zoospores during the rainy season. Thus, based on the demand for resistant varieties, various good resistant sources, such as CM334, AC2258, and PI201234, have been reported and their inheritance of resistance studied by many different authorities. However, the mode of inheritance remains unclear, as 1 or 2 independent dominant genes, 3 genes, or multiple genes have all been reported as responsible for resistance. Recently, QTL mappings of the gene factors for resistance have been reported, and molecular markers for resistance used in breeding programs. With the release of many resistant commercial hybrid cultivars, differentiation of pathotypes of the pathogen is attracting interest among breeders and plant pathologists. Various authorities have already classified the pathogen strains into different races according to the inter-action between resistant host plants, including the source of resistance, such as CM334 and PI201234, and resistant commercial varieties and P. capsici isolates. However, no standard differential host sets have yet been established, so the results are good only for the pathogen strains used in the experiments. Thus, for breeding varieties with durable resist-ance, it is important to introduce resistance from different sources and use diverse local pathogen strains collected in the target area for distribution in a breeding program.

• The Korean Journal of Mycology
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• v.47 no.1
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• pp.1-12
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• 2019

This study was conducted to investigate the optimum culture conditions, for mass production of Tremella fuciformis in M9 basic medium. The strain KMCC04674, used in this study was identified T. fuciformis by internal transcribed spacer (ITS). To define the optimum conditions for the mass production of T. fuciformis, we investigated the effects of different culture conditions and various nutrient sources on the fungal growth. The optimum initial pH and temperature for the fungal growth were 5.0 and $25^{\circ}C$, respectively. The optimal composition of the growth medium was 4.0% mannitol, 3.0% $NH_4H_2PO_4$, 1.0% malt extract, 1.0% glutamic acid, 5mM $CaCl_2$, and 0.5% glucanic acid.

• Journal of Practical Agriculture & Fisheries Research
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• v.19 no.1
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• pp.83-90
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• 2017

In order to develop the culture material for breeding of Lentinula edodes, dikaryotic and monokaryotic mycelia were cultured in agar and sawdust medium. The cultivars were used Sanjo No. 701, Sanjo No. 705, Chamaram and Chuje No. 2 in this study. The mycelial growth of the cultivars were highest in PDA except for Sanjo No. 705, but Sanjo No. 705 showed the best mycelial growth in MCM. Regardless of the cultivars, the mycelial growth showed the most stable in MEA. There was no significant difference in mycelial growth among the cultivars in sawdust medium, but it was about 10% faster than that of Sanjo No. 701 and 705. Monokaryotic strains of Sanjo No. 701 and Chamaram showed less mycelial growth than dikaryotic mycelium. Dikaryotic mycelium of Chamaram showed better mycelial growth than that of Sanjo No. 701, but monokaryotic mycelium of Chamaram showed lower mycelial growth than Sanjo No. 701. The selected monokaryotic mycelium has a wide varience of mycelial growth, and the morphologies of the colonies are very diverse, so those are presumed that wide variences of monokaryotic are selected in genetically, and these monokaryotic mycelium are expected to be a good breeding materials.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.277-285
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• 2023

The onion moth, Acrolepiopsis sapporensis, was monitored in the farms cultivating the welsh onion, Allium fistulosum, using sex pheromone from transplantation to harvest. Two occurrence peaks were observed at early June and late July after the overwintering population. However, the population sizes were varied among different years and the cultivating environments. To effectively control A. sapporensis with microbial pesticides, different Bacillus thuringiensis strains were screened to select B. thuringiensis kurstaki (BtK). To enhance the insecticidal virulence of BtK, the culture broth of Photorhabdus temperata temperata (Ptt) was added to the BtK. This mixture of two entomopathogenic bacteria was called 'BtPlus', which was superior to BtK alone in the insecticidal virulence. The enhanced virulence was explained by the immunosuppressive activity of the secondary metabolites contained in the Ptt extract. The metabolites inhibited both cellular and humoral immune responses of A. sapporensis, resulting in the enhanced virulence of BtK. These results suggest that A. sapporensis occurs in the welsh onion fields and the resulting economic damage would be effectively prevented by BtPlus application.

• Journal of Animal Science and Technology
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• v.52 no.1
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• pp.65-70
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• 2010

A bacterium producing acidic cellulase was isolated from pig feces. The isolate, ATC6 strain, was found to be Gram-positive, non-motile, catalase-positive, and spore-forming stain. Under an electron microscope, the cells were observed to be rod-shaped. The isolate was identified as Bacillus amyloliquefaciens ATC6 on the basis of morphological and biochemical properties as well as 16S rRNA gene sequences. Optimum pH and temperature for the cellulase activity of the culture supernatant of B. amyloliquefaciens ATC6 were found to be pH 4.5 and $55^{\circ}C$, respectively. More than 80% of its maximum activity was maintained at pH 4.0. The cellulase activity was maintained at temperatures ranging from 35 to $55^{\circ}C$ after 2 h incubation at pH 4.5, whereas it's activity decreased rapidly at $65^{\circ}C$.

• Research in Plant Disease
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• v.8 no.3
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• pp.184-188
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• 2002

An antagonistic bacteria, Bacillus licheniformis Nl strain which effectively inhibited mycelial growth of gray mold rot pathogen, Botrytis cinerea was isolated from the rhizosphere of perilla crop. Powder soy formulation by B. lichentfomis Nl strain as a biocontrol agent was developed far the first time and estimated its control effect on perilla leaves in this study. First of all, far the mass production of antifungal metabolites of B. lichentfomis Nl strain in flask liquid culture, the most effective carbon and nitrogen source were selected as glucose and tryp-tone, respectively, For the formulation, vegetative biomass of B. licheniformis Nl strain from 5-day-old liquid culture in nutrient broth added glucose and tryptone was mixed with soy flour, rice flour glucose, FeSo$_4$~7$H_2O$, and MnCl$_2$. 4$H_2O$, and dried and pulverized. In plastic house test, powder soy formulation effectually controlled gray mold rot as the control value of 93.1 %, was more effective than chemical fungicide, benomyl showing the control value of 86.1%. Thus, development of powder soy formulation of B. lichentfomis Nl will aid large-scale application of biological control in field trials.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.51-58
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• 2001

Entomopathogenic fungus, Paecilomyces japonicus, has been commercially used as medicinal purpose . The silkworm, Bombyx mori, as an optimal host for the fungi, has been selected and used for the production of the fungal fruit bodies. In current method, newly molted fifth instal larvae should be exposed to the adverse stress environment of high temperature (3$0^{\circ}C$), high relative humidity ( 90%), and starvation for 24h for better fungal inoculation to the host insects. In this study, an alternative method using chemical agent, dexamethasone (DEX: an eicosanoid biosynthesis inhibitor), was tried to get the immunodepressive effect on the larvae to elevate the inoculation rate of the fungi to the silkworm without any harsh rearing environment. DEX (100$\mu\textrm{g}$) showed significantly synergistic effect on the hemocyte lethality of the fungus, and was effective to decrease cellular immune responses measured by the number of hemocyte microaggregation and phenoloxidase activity of the fifth instar larvae in response to the fungal injection. A detergent of 0.05% Triton-X was effective to increase the in- oculation rate of the fungi to the larvae and used in all fungal spraying solutions. Without any environ- mental stress treatment, only DEX (100$\mu\textrm{g}$) injection to the fifth instar larvae followed by the fungal spray was effective to get the inoculation rate equivalent to the current fungal spray method requiring harsh rearing environment. These results suggest that the inoculation of P. japonicus can be elevated by the help of DEX and that the silkworms use eicosanoids to elicit cellular immune response against fungal pathogen.

• Applied Biological Chemistry
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• v.32 no.4
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• pp.416-423
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• 1989

In order to produce clear and favorable citrus wine from Citrus unshiu produced in Cheju island, chemical and microbiological processes for alcoholic fermentation were investigated. The ratio of pressed juice passed below 100 mesh sieve and peel of mandarin orange were 55.9% and 25.6% respectively. Orange juice for fermentation source contained 8.85% total sugar, 1.43% total acid and 0.056% volatile acid. Pressed juice was adjusted to 24 degree Brix with cane sugar, and was fermented at $20^{\circ}C$ for one month. Starter screened and selected was Saccharomyces cerevisiae IAM 4274. As principal fermentation proceeded for one week, suspended solids began to precipitate slowly after then. After fermentation, clear citrus wine consisted of about 8 degree Brix residual sugar, $13.3{\sim}14.4%$ ethanol, $0.78{\sim}1.11%$ total acid, $0.05{\sim}0.07%$ methanol and $2.25{\sim}3.29%$ extract, was obtained. Color, flavor and taste of citrus wine found good with panel test. Citrus wine which was treated with fungal enzyme derived from Aspergillus niger CCM-4 was cleared much faster, and could be filtered more rapidly than the untreated. The enzyme-producing strain was isolated from field soil of Cheju island and identified.

• KSBB Journal
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• v.14 no.1
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• pp.103-108
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• 1999

A bacterium having strong fibrinolytic activity, S7-16 strain, was isolated from soil. The isolated bacterium was identified and named as Bacillus sp. S7-16. The optimal composition of the medium for the production of fibrinolytic enzyme by Bacillus sp. S7-16 was 0.5%(w/v) polypeptone, 0.5%(w/v) yeast extract, 0.3%(w/v) NaCl, 0.1% (w/v) $KH_2PO_4,\;0.3%(w/v)\;K_2PHO_4,\;and\;0.01%(w/v)\;MgSO_4{\cdot}7H_2O$. The optimal temperature and initial pH of the medium for the production of the enzyme were $35^{\circ}C$ and 7.0, respectively. The maximum production of the fibrinolytic enzyme was obtained after 24 hours of the incubation. Under the above conditions, the culture supernatant had strong fibrinolytic activity. Within pH4~11, the crude fibrinolytic enzyme was stable. The enzyme was stable up to $50^{\circ}C$. The optimum pH and temperature for the enzyme activity were around 7.5 and $40^{\circ}C$, respectively.