• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.696-699
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• 1990

Some mixed culture systems consisting of koji molds and yeast were tested for the ethanol production by simultaneous saccharification and fermentation using polished rice as the substrate. Aspergillus shirousamii showed the highest ethanol production in the mixed culture with Saccharomyces cerevisiae on steamed rice added with 150 ml water in 250 ml Erlenmeyer flask. The optimum initial pH, temperature and specific surface for the ethanol production in this system were 6.5, $30^{\circ}C$, and 0.1, respectively. Under this condition, 12.9% ethanol was produced with inoculation with $5{\times}10^2$ conidia/ml of A. shirousamii and $5{\times}10^6\;cells/ml$ of S. cerevisiae in 10 days.

• Journal of the Korean Home Economics Association
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• v.23 no.4
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• pp.69-78
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• 1985

The effects of the garlic preparation on the response of normal and cancer-stricken mice were studied. Food consumption of skin cancer-stricken group decrease more rapidly than that of normal group as cancer of skin develops, but here was no observable change in garlic groups. The rate of weight of increase was the highest in skin cancer-stricken group whereas that of garlic groups was reduced. The feed efficiency ratio was found to be very high in the normal group, whereas that in other goups after inculation of cancer cell was lower. The total protein content of serum was the highest in skin cancer-stricken group was observed to have more conspicuous tumor than other groups, the simultaneous administration of experimental diet and but inoculation of cancer cell produced more severe tumours. It appears that the garlic may exhibit the tendency to reduce the propagation of skin cancer of mice.

• Journal of Mushroom
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• v.3 no.3
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• pp.109-114
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• 2005

Attempts were made to control Diatrype stigma occurred on the bed-log of shiitake by resistant shiitake strains. In selection test of resistant shiitake strains, 67 out of 77 strains tested were proved to be resistant to D. stigma. Among them, 13 strains including KFRI 5 were effective to inhibit the access of D. stigma, and 7 strains including KFRI 180 remarkably invaded the territory of D. stigma. Among 31 shiitake strains made by hybridization of resistant strains for D. stigma, 8 strains including KFRI 537 inhibited the access of D. stigma, and 4 strains including KFRI 545 invaded the territory of D. stigma. The effects of temperatures and inoculation orders to the resistance were confirmed in PDA plates and test tubes filled with sawdust of Quercus acutissima. Four kinds of temperature treatments as follows were tested: (1) continuous incubation at $14^{\circ}C$, (2) continuous incubation at $25^{\circ}C$, (3) changing of incubation temperature from $14^{\circ}C$ to $25^{\circ}C$ as soon as mycelia of both shiitake and D. stigma meet together, (4) changing of incubation temperature from $25^{\circ}C$ to $14^{\circ}C$ as soon as mycelia of both shiitake and D. stigma meet together. Three kinds of inoculation procedure were tested: (1) inoculation of shiitake 3 days ahead of D. stigma inoculation, (2) inoculation of D. stigma 3 days ahead of shiitake inoculation, (3) simultaneous inoculation of both fungi. In PDA plate test, the strain KFRI 137 showed outstanding ability to inhibit mycelial growth of D. stigma and the strain KFRI 180 invaded into the territory of D. stigma in most of treatments. Hybrid strains, KFRI 545, 546, and 547 were more resistant than their parent strains, KFRI 488 and 405. In test tube examinations, all the strains of shiitake showed high resistance at the treatment of change in temperature from $14^{\circ}C$ to $25^{\circ}C$ when mycelia of both shiitake and D. stigma meet together. On the other hand, resistance of all the strains growing at $25^{\circ}C$ decreased when the temperature was changed into $14^{\circ}C$ after mycelia of both fungi. In these cases, the resistance reached to 7~20% of the highest resistance. The strain KFRI 259 invaded the territory of D. stigma, contrary to PDA plate test. Among the strains, KFRI 393 strain was the most resistant under the continuous incubation at $25^{\circ}C$.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.117-122
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• 2007

This study was investigated the potential of ducks and fish trap for the control of golden apple snail, Pomacea canaliculata, in paddy field and water canals. The smaller size of duck (700g) preyed snails than the bigger one (1,300g). The consumption of two ducks was bigger under plastic house. They preyed over 90% on the second days of release. The release time of ducks was more effective at seven days after inoculation of snails than simultaneous. Duck could suppress the density of snails at any time from month after inoculation. Four ducks per $30m^2$ could control snails in an irrigation canals. The number of attracted golden apple snail per week was 216 in big fish trap $({\Phi}15cm)$ with menthol paste which for a carp.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.160-164
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• 1999

Algicidal activities of Alteromonas sp. SR-14 against Chaetoceros calcitrans were investigated at various culture conditions. The algicidal activity by Alteromonas sp. SK-14 was dependent on temperature. In mixed culture of C, calcitrans and Alteromonas sp. SR-14 at various temperatures, the algicidal activity of Alteronzonas sp. SR-14 was the highest at $20^{\circ}C$, but not showed algicidal activity above $25^{\circ}C$. With the inoculation of $10^4$ cells/ml of C. calcitrans, the diatom could not grow at the microalgal culture condition until 15 days by the simultaneous inoculation of less than 10 cells/ml of Alteromonas sp. SR-14. Alteromonas sp. SR-14 showed the strongest algicidal activity against logarithmic phase cells of C. calcitrans. During the mixed culture of C. calcitrans and Alteromonas sp. SR-14, supplementation of Conwy medium nutrients, changes of light intensity with 1,300$\~$4,600 lux and agitation with 200 rpm did not affect the algicidal activity.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.229-234
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• 1989

Cooked soybeans were fermented with B. subtilis and B. natto for 48 hrs and 74 hrs. The odor concentrates of during these Chungkookjang fermentation were obtained with a simultaneous distillation and extraction system. The seperation and identification were carried out by GC and GC-MS. The main components of the cooked odor concentrate of soybeans were 3-methyl-1-butanol, 1-pentanol and 1-octen-3-ol etc.. In Chungkookjang (B. subtilis inoculation), 3-methyl-1-butanol, 1-pentanol and 1-octen-3-ol remained but alkyl pyrazines such as 2,5-dimethyl pyrazine, trimethyl pyrazine and tetramethyl pyrazine increased and those increased during the fermentation. In Chungkookjang(B. natto inoculation), 3-methyl-1-butanol, 1-pentanol and 1-octen-3-ol, main components of cooked soybeans decreased and alkyl pyrazines increased, especially, tetramethyl pyrazine remarkably increased during fermentation. From the result, it seems that alkyl pyrazines caused the characteristic odor of Chungkookjang and mask the beany odor.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.721-725
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• 1989

Aflatoxin accumulation by Aspergillus flavus in rice was inhibited by A. kawachii and A. Shirousamii so that the rate of toxin accumulation and the maximum concentration of accumulated aflatoxins were considerablly reduced, although the initiation of aflatoxin accumulation was not affected. The maximal accumulated aflatoxin $B_1$ in rice by A. flavus at $28^{\circ}C$ and 85% RH was $40{\mu}g/50g$ rice after 35 days. Under the same condition but the additional inoculation of A. kawachii, $25{\mu}g\;of\;aflatoxin\;B_1$ was accumulated maximally in 50g rice after 45 days. When A. shirousamii was inoculated simultaneously with A. flavus on rice, however, only trace levels of aflatoxins were detected throughout 60 days of storage. Aflatoxins added to rice were reduced by 97% with A. kawachii and by 98% with A. shirousamii after 7 days during rife koji preparation. They were also reduced after 48 Hours of incubation by 30-67%, with A. kawachii koji and by 16-75% with A. shirousamii koji.

• Applied Biological Chemistry
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• v.42 no.2
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• pp.111-115
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• 1999

This study was attempted to develop technique of masking the pungent odor of chonggugjang using two-stage fermentation method with mixed pure cultures. Cooked soybeans were fermented with Lactobacilli or Aspergillus oryzae at $38^{\circ}C$ for 36 hrs, and then re-fermented with Bacillus subtilis for 12 hrs. The volatile compounds of chonggugjang were obtained with a SDE(Simultaneous steam Distillation and solvent Extraction) system and the extracts were identified by GC and GC-MS. The experimental results revealed the presence of 35 volatile compounds in control chonggugjang(only Bacillus subtilis inoculation). Among them, the major volatile compounds were 2,5-dimethyl pyrazine, 2,3,5-trimethyl pyrazine and 2-methyl pyrazine. Twenty-nine kinds of volatile compounds were in chonggugjang prepared by two-stage fermentation method with Lactobacilli and Bacillus subtilis(II), and major volatile compounds were identified to be 2,3,5-trimethyl pyrazine and 2,5-dimethyl Pyrazine. In chonggugjang(Asp. oryzae and then Bacillus subtilis inoculation(III)), the contents of hexadecanoic acid and 2-methyl pyrazine were patricularly high and the main components of chonggugjang fermented with rice straw(IV) were 2,5-dimethyl pyrazine, 2,3,5-trimethyl pyrazine etc. In conclusion, the flavor compounds such as 2, 5-dimethyl pyrazine, 2,3,5-trimethyl pyrazine and 2-methyl pyrazine were increased by the inoculation of Lactobacilli or Asp. oryzae, where as unpleasant odor components-butyric acid and valeric acid were decreased. Compared with volatile compounds of chonggugjang made from different soybean cultivars, the flavor compounds (2-methyl pyrazine 2,5-dimethyl pyrazine 2,6-dimethyl pyrazine 2,3-dimethyl pyrazine 2-acetyl pyrazine 2,3,5-trimethyl pyrazine 2-ethyl-3,5-dimethyl pyrazine) of chonggugiang prepared with Sinpaldalkong were high.

• Journal of the Korea Convergence Society
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• v.13 no.2
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• pp.67-75
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• 2022

The purpose of this study is to present an appropriate management plan as a supplement to the scientific evidence of the currently operated distancing system for preventing COVID-19. The currently being used mathematical models are expressed as simultaneous ordinary differential equations, there is a problem in that it is difficult to use them for the management of entry and exit of small business owners. In order to supplement this point, in this paper, a method for quantitatively expressing the risk of infection by people who gather is presented in consideration of the allowable risk given to the gathering space, the basic infection reproduction index, and the risk reduction rate due to vaccination. A simple quantitative model was developed that manages the probability of infection in a probabilistic level according to a set of visitors by considering both the degree of infection risk according to the vaccination status (non-vaccinated, primary inoculation, and complete vaccination) and the epidemic status of the virus. In a given example using the model, the risk was reduced to 55% when 20% of non-vaccinated people were converted to full vaccination. It was suggested that management in terms of quarantine can obtain a greater effect than medical treatment. Based on this, a generalized model that can be applied to various situations in consideration of the type of vaccination and the degree of occurrence of confirmed cases was also presented. This model can be used to manage the total risk of people gathered at a certain space in a real time, by calculating individual risk according to the type of vaccine, the degree of inoculation, and the lapse of time after inoculation.

• The Plant Pathology Journal
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• v.24 no.4
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• pp.400-406
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• 2008

To examine the relationship between plant hormones and the development of pepper anthracnose, we investigated the effects of several plant hormones on the progression of disease symptoms. Of the five plant hormones examined, abscisic acid (ABA) increased the lesion length and disease incidence on detached fruits of Capsicum annuum cv. Nokkwang. The simultaneous application of ABA with inoculation of Colletotrichum acutatum JC24 resulted in increased lesion length, depending the concentration of ABA applied. Additionally, application of ABA caused the development of pepper anthracnose in fruits of Capsicum baccatum cvs. PBC80 and PBC81, which were previously resistant to the disease. Furthermore, ABA administration rendered increased pathogenicity of other isolates of C. acutatum BAC02063, PECH10, and TCBNU3 obtained from the Chinese matrimony vine, peach, and tea tree, respectively. Our data suggest that exogenous ABA may result in the suppression of defense mechanisms of pepper fruits against anthracnose, which leads to a change in the susceptibility of pepper fruits and the development of pepper anthracnose.