• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.191-198
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• 1977

This study was conducted to determine the inheritance to bacterial leaf blight in rice. Varieties used in the study were IR1544-349-2, IR1698-237-2, IR1529-680-3, IR28, IR29, RP663-337-7-8-4-1-1, RP291-20, 62-595 and Kele. The isolate of bacteial leaf blight used was 71-23, 76-1 of Xanthomonas oryzae. $F_1s$ were obtained from crosses between resistant and susceptible varieties. Field observation was made from the Parents, $F_1s$ and $F_2$ sagregating population. The result is summaryzed as fallow: 1) The resistance to the bacterial leaf blight (71-23) derived from cultivars IR1529-680-3, IR28, IR29, RP663-337-7-8-4-1-1, RP291-20 and 62-595 was controlled by a single dominant gene. 2) The resistance to the bacterial leaf blight (71-23) derived from cultivars IR1545-339-2, IR1544-340, IR1698-237-2 and Kele was controlled by a single recessive gene. 3) The resistance to the bacterial leaf blight (76-1) derived from cultivars IR1545-339-2, IR1544-340, IR 1698-237-2 was controlled by a single dominant gene. 4) Degree of resistance to the bacterial leaf blight and genetic type were different depending on isolates within the same resistant cultivar. 5) There was no relation between resistance to the bacterial leaf blight and heading days.

• Research in Plant Disease
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• v.19 no.1
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• pp.12-20
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• 2013

To isolate antagonistic bacteria against sclerotinia rot of lettuce, caused by Sclerotinia sclerotiorum, soil samples were collected from the diseased greenhouse field in Namyangju city, Gyeong-gi province from 2007 to 2008. A total of 196 bacterial isolates were isolated using serial dilution method. In dual culture assay in vitro, 26 isolates showed more than 80% of inhibition rates of mycelial growth of S. sclerotiorum. Based on 16S rDNA sequence analysis, the 26 isolates were identified as Bacillus megaterium, B. cereus, B. subtilis, Arthrobacter nicotianae, A. ramosus, Pseudomonas filiscindens, Stenotrophomonas maltophilia, Brevibacterium frigoritolerans and Sphingobacterium faecium. The 26 isolates inhibited the mycelial growth of S. sclerotiorum up to 80% and the sclerotial germination 0-100%. In the greenhouse pot test of ten isolates conducted in summer, 2 isolates B. megaterium (DK6) and B. cereus (C210) showed control efficacy on sclerotia viability of S. sclerotiorum, 20% and 35%, respectively. In the greenhouse pot test in winter, the disease incidence of the control group was 80%, whereas those of 9 isolates among 26 were approximately 20%. From the result, the 9 isolates are expected as potentially antagonistic bacteria for biological control of sclerotinia rot of lettuce caused by S. sclerotiorum.

• Korean journal of applied entomology
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• v.17 no.1 s.34
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• pp.23-28
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• 1978

The study has been carried to confirm the pathotypes of Kresek inducing isolates of X. oryzae, and its reaction to the test plants when they were inoculated by the use of various methods. Induction of Kresek symptom by 23 isolates which randomly samplified from 123 Kresek areas through the country also were examined. The specificity of Pathotypes I, II, V in causing Kresek and the potenciality of infected rice straw is a first inoculum for Kresek epidemics in nature were tested. Fifteen out of 23 isolates from kresek area belonged to pathotype group I, while the rest of 8 isolates 5 howed group II reaction, and the most of isolates were originated from infected rice plant of Milyang #23. All of five pathotype groups were abled to produce 'Kresek' symptom although they showed some differences in each group of pathotype. The varieties Milyang #21, 22 and 23 were attacked by all isolates of group I, II and V while the Gogyoku group varieties including Yushin produced kresek symptom only by pathotype group II. Infected and dried straw maintained the pathogens during the winter period, and these straw acted as a first inoculum of Kresek disease when the straw were cutted and used as a manure just before transplanting of rice seedling.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.237-248
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• 2006

Forty one compounds such as ester, sulfonyl ester, carbamate, ether and phosphoyl ester derivatives of thymol(I) and carvacrol(II) were synthesized. These derivatives were identified by IR, GC/MS and $^1H$-NMR spectra. Their antifungal activities were tested against various plant pathogenicfugi. Among them, several compounds were showed potent in vivo antifungal activities. The selected compounds showing in vitro antifungal activities were tested in vivo antifungal activities aganint 5 plant diseases such as rice blast, rice sheath blight, tomato late blight, cucumber anthracnose, and cucumber gray mold. As a result, 2-isopropyl-5-methylphenylacetate(I-1a) effectively suppressed the development cucumber gray mold and rice blast. Methyl(2-isopropyl-5-methylphenoxy)acetate(I-6d) and ethyl 4-(5-methyl-2-isopopylphenoxy)crotonate(I-7d) also showed potent in vivo antifungal actively againt rice sheath blight and tomato late blight, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.75-80
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• 2002

The growth inhibition by nisin-Producing lactococci against Bacillus subtilis and its application to doenjang fermentation were investigated. Lactococcus lactis subsp. lactis IFO 12007, L. lactis subsp. lactis ATCC 7962 and L. lactis subsp. lactis ATCC 11454 were used as nisin-producing lactococci. All of three strain rapidly proliferated to more than 10$^{9}$ CFU/g in steamed soybeans. Only L. lactis subsp. lactis IFO 12007 was in steamed soybean without any pH decrease. In spite of the mild decrease in pH, the growth of B. subtilis was completely inhibited; no living cells were detected in a soybean sample inoculated with 10$^{6}$ CFU/g and incubated for 24 to 72h. The L. lactis subsp. lactis IFO 12007 was applied to doenjang fermentation as a starter culture. It produced high nisin activity in steamed soybean, resulting in the complete growth inhibition of B. subtilis, which had been inoculated at the beginning of the meju fermentation, throughout the process of doenjang production. Over-acidification, which is undesirable for doenjang quality, was successfully prevented simply by adding salt which killed the salt-intolerant L. lactis subsp. lactis IFO 12007. Furthermore, the nisin activity in doenjang disappeared with aging.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.8
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• pp.1167-1173
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• 2009

This study was conducted to evaluate the effects of providing fermented soy protein to weaned pigs on nitrogen balance and apparent fecal and apparent ileal digestibility (AID) of AA. Four weaned ((Yorkshire${\times}$Landrace)${\times}$Duroc) barrows (BW = 6.58${\pm}$0.98 kg), surgically fitted with a simple T-cannula approximately 15 cm prior to the ileo-cecal junction, were fed four diets according to 4${\times}$4 Latin square design. Diets were a basal diet supplemented with one of the following: 3% SDPP (spray dried plasma protein), 5% RBP (soy protein fermented by Lactobacillus spp.), 5% PSP (soy protein fermented by Aspergillus oryzae and Bacillus subtilis), and 2.5% RPP (2.5% RBP+2.5% PSP). No differences were observed in DM and N intakes among treatments. However, the level of urine excretion was greater in the RPP group than in the PSP group. Additionally, fecal DM excretion, fecal N concentration and fecal N excretion were increased in the RBP, PSP and RPP groups when compared with the SDPP group (p<0.05). Furthermore, total excretion was increased in the RPP group when compared with the PSP group (p<0.05). In addition, N absorption and the N absorption ratio were higher in the SDPP group than in the RPP group (p<0.05). Moreover, the DM and N digestibilities were lower in the RBP, PSP and RPP groups than in the SDPP group (p<0.05), and the ash and energy digestibilities were higher in the SDPP and RBP groups than in the PSP and RPP groups (p<0.05). However, no significant differences were observed in the DM, N, Ash, Ca, P or ileal digestibilities among treatments, although the energy digestibility was higher in the SDPP group than the RBP group (p<0.05). In addition, the apparent ileal digestibilities of essential amino acids (Arg, His, Iso, Leu, Lys, Phe, Thr, and Val) were significantly higher in the SDPP group than in the other groups (p<0.05), and the levels of Ala, Cys, Glu and Try were greater in the SDPP treatment group than the RBP, PSP and RPP groups (p<0.05). Additionally, the levels of Asp, Gly and Ser were higher in the SDPP group than the PSP and RPP groups, and the level of Pro was higher in the SDPP group than the RPP group (p<0.05). Finally, total non-essential amino acid and total amino acid digestibility were higher in the SDPP group than in the other treatments (p<0.05). Taken together, the results of this study indicate that animal protein is more bioavailable than plant protein. However, the N absorption ratio and ileal digestibility were found to be similar in the SDPP and RBP groups.

• Korean journal of applied entomology
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• v.4
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• pp.19-24
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• 1965

In an attempt to find a satisfactory environmental factors which facilitate abundant conidial production of Piriculariaoryzae Cav. on tomato juice media, various environmental factors were studied for their effect on sporulation and mycelial growth of the fungus. Those factors were conditions of irradiation, color of light, age of culture and pH of the media. l) Continuous exposure to fluorescent light (Mitsubish FL-20-35 W) produced more conidia and much mycelial growth than did intermittent photoperiods and darkness. 2) Of 3 cellophane filters and direct exposure to fluorescent light used, conidia were produced best under the direct exposure to the light. Conidial production in color filter conditions sequently decreased with red, yellow and blue. Growth of mycelium was not significantly different within colors. 3) Periodic irradiation of 12-hour unit brought about zones on mycelial growth no matter what the color filter was used. 4) Older cultures responding to the light were more stimulated by light than were the younger one in the conidia production, but maximum production of conidia was 48 hours of age in this case. 5) Color of the mycelial mat and the aerial mycelium seemed to have a close relation to the production of conidia. The more darkness of the mycelial mat was produced the more conidia and the much aerial mycelium was produced the least conidia. The color of mycelium was more dark under the continuous irradiation than continuous darkness, while the periodic irradiation showed intermediate effect. 6) The concentration of hydrogen ion for growth and sporulation of the fungus was investigated the ranges between 5 and 9. The best pH for the fungus was also noted at 7. whereas the below of pH 4 was not occurred any mycelial growth and sporulation.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.1
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• pp.48-54
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• 2007

Bacillus polyfermenticus SCD (B. polyfermenticus SCD) has been appropriately used for the therapy of long-term intestinal disorders, because live strains in the form of active endospores can successfully reach the target intestine in humans. B. polyfermenticus SCD produces the most antibiotic-related materials. In the present study, B. polyfermenticus SCD was fermented with soybeans (BPFS) and its probiotic properties were investigated. B. polyfermenticus SCD and BPFS showed a broad spectrum of antimicrobial activity against pathogenic Gram-positive (Streptococcus parauberis, Streptococcus iniae, Lactococcus garviae) and Gram-negative (Flexibacter tractuosus, Vibrio harveyi, Vibrio vulnificus, Vibrio ordalii) bacteria and moulds (Aspergillus niger, Aspergillus oryzae). Sebastes schlegeli were used to examine survival rate and cleanup action by BPFS. Bacterial infection resulted in a mortality of up to 99% in the commercial fodder fed groups. BPFS both enhanced the growth rate of fry by improving their appetite and had cleaned by decreased eutrophication. Therefore, it seems appropriate that BPFS should be developed as an antibiotic replacement, favorable fodder additive, and antifungal material in fish farming systems.

• Korean Journal of Poultry Science
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• v.30 no.1
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• pp.11-16
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• 2003

This study was conducted to investigate chemical and sensory characteristics of boiled soup extracted from crossbred ogol chicken as affected by the level of Flavourzyme produced from Aspergillus oryzae and composed with endo-proteinase(674U/g) and exoproteinase(8,053U/g). It was hydrolyzed by different concentrations of the protease enzyme (Flavourzyme)(0%(Control), 0.01％(T$_2$), 0.1%(T$_3$) and 0.5%(T$_4$)) at 45$^{\circ}C$ for 4hrs. Manufacture of the extract was performed by boiling treated meats with medicinal herbs(Sipchun daebo) at a higher pressure condition. Minerals, free amino acid content, sensory properties of the extract were as follows. The sodium contents were increased as the treatment levels of enzyme increased. The iron contents were lowest when the enzyme treated by 0.5% level, however there were not significantly different among the treatments. The copper and mangan contents had no significantly different among the enzyme treatment levels. Higher contents of fee amino acid were observed as the amount of the protease increased with the treatment of higher than 0.1％ enzyme, no significant effect was observed. In sensory properties, the extract manufactured by addition of 0.01∼0.1% of Flavourzyme resulted in a similar or better appearance, flavor, taste and overall palatabilitycompared to control(no enzyme treatment). However, the extract manufactured with 0.5% of Flavourzyme resulted in lower scores in appearance, flavor, taste and overall palatability than the control. In addition, this product showed more off-flavor than control.

• Applied Biological Chemistry
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• v.35 no.4
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• pp.237-241
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• 1992

The protease from Halomonas sp. ES 10 was purified by methanol precipitation, gel filtration on Sephadex G-150 and G-200, and ion exchange chromatography on DEAE-Sephadex A-50. The purified enzyme was found to be homogeneous by polyacrylamide gel electrophoresis. The specific activity of purified enzyme was 1,014 units/mg protein, and the yield of the total activity from the culture filtrate was 7%. The optimal temperature and pH for the enzyme activity were $35^{\circ}C$, and pH 11.0, respectively. And the enzyme was stable in the range of $pH\;7.5{\sim}11.0$. The residual activity of the enzyme was 70%, when the enzyme was incubated at $50^{\circ}C$ for 40 min. The Km value of the enzyme was 7.4 mg/ml to milk casein. $Li^+$, $Ca^{2+}$, SDS and Tween 80 were appeared to activators, whereas $Hg^{2+}$ and EDTA to inhibitors. The addition of DFP and PMSF showed the relative enzyme activities of 63% and 107%, respectively, suggesting that the enzyme may not belong to serine type protease. When the alkaline protease was treated with 0.5 M and 1 M NaCl, the relative enzyme activities were 95% and 65%, respectively. This enzyme showed 20% and 15% higher enzyme activity than that of Aspergillus oryzae (Sigma Chemical Company product, P4755) in the presence of 0.5 M and 1 M NaCl.