• Journal of Bio-Environment Control
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• v.11 no.3
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• pp.149-150
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• 2002

• Korean journal of applied entomology
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• v.60 no.2
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• pp.203-214
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• 2021

This study aimed at establishing a packaging standardization method that allows the maintenance of biological control agents product quality during delivery. First, based on the results of distribution status analysis of biological control agent products from four manufacturers, we confirmed that the mean temperature was maintained at 25.6℃ (minimum and maximum temperatures.: 18.1 and 30.7℃, respectively) inside the packaging box of each company for 36-48 h. To establish the optimal packaging method for each season, seven external temperature conditions were set ranging between 0℃ and 30℃ at intervals of 5℃. In addition, we evaluated internal temperature maintenance performance for each coolant pack handling method and determined 14 packaging combinations. A packaging combination that maintained a temperature of 3℃ - 9.9℃ at each external temperature conditions was considered efficient. This temperature range is close to a lower developmental threshold at which the biological control agents can survive with minimum energy for 12 h (direct delivery time), or 36-48 h (general delivery time) after packaging.

• The Plant Pathology Journal
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• v.22 no.3
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• pp.278-282
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• 2006

Bacillus vallismortis EXTN-1, a biocontrol agent in cucumber, tomato and potato was tested in rice pathosystem against rice fungal pathogens viz. Magnaporthe grisea, Rhizoctonia solani and Cochliobolus miyabeanus. Apart from increasing the yield in the bacterized plants (11.6-12.6% over control), the study showed that EXTN1 is effective in bringing about disease suppression against all the tested fungal pathogens. EXTN-l treatment resulted in 52.11% reduction in rice blast, 83.02% reduction in sheath blight and 11.54% decrease in brown spot symptoms. As the strain is proven as an inducer for systemic resistance based on PR gene expression in Arabidopsis and tobacco models, it is supposed that a similar mechanism works in rice, bringing about disease suppression. The strain could be used as a potent biocontrol and growth-promoting agent in rice cropping system.

• Journal of environmental and Sanitary engineering
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• v.15 no.3
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• pp.24-30
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• 2000

In this study, to determine the optimum fermentation process for the feed production of food wastes and estimate the practical value of fermented feed using kudzu creeper and sawdust as bulking agent. This study considered initial C/N ratio control as the fermentation process variables. The result are summarized as follows. Minimum water contents of byproducts in the fermentation feed production showed 39%(kudzu), 37%(sawdust) at the C/N ratio 25 and 45%(kudzu, sawdust) at the C/N ratio 35. Temperature variations in the fermentation feed production at the C/N ratio 25 indicated $68^{\circ}C$(kudzu), $70^{\circ}C$(sawdust). Optimum condition of fermentation process of water content, C/N ratio and permeability (porous structure of the mixture). For optimum fermentation gravitationally dewatered garbage, the proper mixing ratios of kudzu(moisture contents : 17.3%) and sawdust(moisture contents : 13.2%) were 41% and 39%, respectively. Major biological reaction in the aerobic fermentation feed production occurred during 12~24hrs.

• The Plant Pathology Journal
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• v.40 no.2
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• pp.160-170
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• 2024

Erwinia amylovora is a plant pathogen that causes fire blight on apples and pears. Bacteriophages, which are viruses that selectively infect specific species of bacteria and are harmless to animal cells, have been considered as biological control agents for the prevention of bacterial pathogens. In this study, we aimed to use bacteriophages that infect E. amylovora as biocontrol agents against fire blight. We isolated bacteriophages Fifi044 and Fifi318 infecting E. amylovora, and characterized their morphology, plaque form, and genetic diversity to use as cocktails for disease control. The stabilities of the two phages were investigated at various temperatures and pH values and under sunlight, and long-term storage experiment was conducted for a year. To evaluate whether the two phages were suitable for use in cocktail form, growth curves of E. amylovora were prepared after treating the bacterial cells with single phages and a phage cocktail. In addition, a disease control test was conducted using immature apples and in vitro cultured apple plantlets to determine the biocontrol effects of the phage cocktail. The two phages were morphologically and genetically different, and highly stable up to 50℃ and pH value from 4 to 10. The phages showed synergistic effect when used as a cocktail in the inhibition of host bacterial growth and the disease control. This study demonstrated that the potential of the phage cocktail as a biocontrol agent for commercial use.

• Microbiology and Biotechnology Letters
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• v.49 no.1
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• pp.24-31
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• 2021

This study aimed to investigate the melanogenesis inhibitory activity of epicatechin-3-O-gallate (ECG) isolated from Polygonum amphibium L. ECG was isolated from the ethanol extract of P. amphibium L, and its chemical structure was determined using spectroscopic methods such as LC-ESI-MS, 1D-NMR, and UV spectroscopy. ECG inhibited the melanogenesis of B16F10 cells in a dose-dependent manner. Particularly, it decreased the melanin content by 27.4% at 200 µM concentration, compared with the control, in B16F10 cells, without causing cytotoxicity. It is noteworthy that the expression of three key proteins, including tyrosinase, tyrosinase-related protein-1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF), involved in melanogenesis, is significantly inhibited by ECG. The ECG isolated in this study caused the inhibition of body pigmentation and tyrosinase activity in vivo in the zebrafish model. These results suggest that the ECG isolated from P. amphibium L. is an effective anti-melanogenesis agent.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.833-837
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• 2006

To determine whether alcohol-treated rat liver cells can be protected by a static magnetic field (SMF), we analyzed the blood chemistry and histology of hepatic tissue removed from alcohol-exposed rats that had been exposed to a static magnetic field. The rats were exposed to a 0.3 tesla (3,000 gauss) magnetic field (MF) for 24 hr daily for 5 weeks with appropriate controls. Glutamic pyruvic transaminase activity and the triglyceride levels in animals exposed to the north (N) or south (S) pole of the MF decreased significantly (p<0.01 and p<0.05, respectively) compared with negative control animals with alcohol exposure. A histological examination of hepatic tissue revealed a moderate to severe accumulation of fat vacuoles of various sizes in the cytoplasm of the hepatocytes of animals in the negative control group throughout the study; whereas in groups exposed to the MF poles, fewer fat vacuoles were seen compared with the negative control group. Electron microscopic observations showed that exposure to the N or S pole protected organelles, including the nucleus, from damage during exposure to this toxic agent, as indicated by the fact that the nucleus and the mithochondria virtually retained their shape throughout this study. These results suggest that exposure to a SMF could be an excellent way of protecting against alcohol-induced damage to the rat liver cell.

• Korean Journal Plant Pathology
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• v.12 no.4
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• pp.407-414
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• 1996

벼 담수직파재배에서 Pythium arrhenomanes 1398에 의한 벼목썩음병의 발병 억제효과가 높은 biological control agent를 배지와 growth chamber 검정을 통하여 선발하고 생물학적 방제 효과를 온실에서 검정한 결과 공시한 66 세균 중 91-110 균주에 의해서만 벼모썩음병의 발병이 억제되었다. CMA 배지 검정에서는 P. arrhenomanes 1398 균주만을 접종한 볍씨는 100% 발병율을 보인 반면 91-110 균주와 P. arrhenomanes 1398 균주를 함께 처리한 경우에는 25.0%가 발병되었으며, 이 효과는 metalaxyl을 처리한 볍씨에서의 21.7% 발병율과 유사하였다. Growth chamber 검정에서는 P. arrhenomanes 1398 균주만을 접종한 볍씨는 27.7% 모 출아율을 보인 반면 91-110 균주와 함께 처리하면 59.1%가 출아되었다. 그러나 91-110 균주에 의한 발병 억제효과는 50% household bleach로 표면 소독한 볍씨에서만 인정되었으며, 이 소독한 볍씨를 91-110 균주의 세균 부유액에 침지하여 3시간 진탕한 후 그 부유액을 따라내고 24시간 배양한 것이 진탕하지 않고 배양한 것에 비하여 모출아율이 54.3%에서 65.7%로 증가되었다. 91-110 균주와 P. arrhenomanes 1398 균주를 함께 처리한 볍씨의 출아율은 62.3%로서 P. arrhenomanes 1398 균주만을 접종한것의 30.8%에 비하여 높았다. 이상과 같이 담수직파한 벼모썩음병의 발병 억제효과가 높은 91-110 균주는 Bacillus brevis로 동정되었다.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.2
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• pp.83-91
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• 2002

The protection of silkworm and its host plants from various kinds of pests parasite and predator is a chronic problem in sericulture. Silkworms and its primary food plants are heavily damaged by large number of pest. The major pests of primary tasar food plants (Terminalia arjuna and Terminalia tomentosa) are the gall insect (Trioza fletcheri minor). Various species of aphids (Eutrichosiphum sp.) have been recorded to damage oak tasar food plants whereas muga silkworm host plants (Machilus bombycina and Litsaea polyantha) are generally attacked by stem bores (Zeuzera multistrigata). Castor (Ricinus communis) is one of the primary host plant of eri silkworm and extensive damage is caused by the castor white fly (Trialeurodes ricini). Insects pests are major enemies of silkworms. Parasites (Blepharipa zebina, Exorista bombycis, Apateles glomeratus), predators (Canthecona furcellata, Sycanus collaris, Hierodulla bipapilla), wasps (Vespa orientalix) and ants (Oecophylla smargdina) continues to cause damage to silk industry. It is estimated that the losses due to parasites and predators are to an extent of 15-20 percent and varies from crop to crop. The complexities in the behaviour and life cycle of pest population existing in semi ecosystem warrant a special attention for their effective management specially in changing scenario for our modern sericulture. Though use of synthetic insecticides has provided us with effective control of almost all major pests and predators, yet their undesirable side effects limit their continued use. Biological control is one of the most important method which can be used to control the pests, parasites and predators population in sericulture. Various potential parasitoids, which can be utilized as an agent of biological control in sericulture have been screened. The natural enemies of the uzi fly (E. bombycis and B. zebina ) are already present in the nature. Nesolynx thymus, Trichria sp., Splangia endius, Dirhinus sp., Trichopria sp., Trichomalopsis apanteloctena and Pediobius sp. are the major parasitoids effective against uzi fly pupa. The scelionid Psix striaticeps and Trissolcus sp. are the Potential egg Parasitoids against stink bug (Canthecona furcellata). Various other native natural potential parasitoids have been screened and suitable strategies have been developed to check the population of pest insect in sericulture.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.253-258
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• 2001

Biological control of thrips with Orius strigicollis Poppius was evaluated in a hot pepper greenhouse. To study the biological control strategy of thrips on hot pepper grown in greenhouse, three plots were established: natural enemy removed plot(CNT), pesticide treated plot(PAT) and O. strigicollis released plot with no pesticide application (NRT). The nymphs of O. strigicollis were found on the leaves of lower stratum in CNT and NRT at 13 days after the first release. The density of thrips was suddenly dropped and maintained at low level since 15 day after transplanting in NRT. The densities of thrips on hot pepper flowers was also maintained at much less level in NRT than in CNT. The thrips and O. strigicollis, which were aggregated in flowers, may have resulted in improved predator searching. Average damage indices of CNT, PAT and NRT were 0.31, 0.05 and 0.08 and the percentage of damaged fruit were 80.0, 17.1 and 24.8% respectively. The damage index and percentage of damaged fruit of NRT was slightly higher than PAT, but very lower than CNT. The introduction of the adults of O. strigicollis, which was the biological control agent for the control of thrips, was effective on hot pepper.