• The Plant Pathology Journal
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• 제36권6호
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• pp.579-590
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• 2020

Botrytis cinerea, which causes gray mold disease in more than 200 plant species, is an economically important pathogen that is mainly controlled by synthetic fungicides. Synergistic fungicide mixtures can help reduce fungicide residues in the environment and mitigate the development of fungicide-resistant strains. In this study, we screened microbial culture extracts on Botrytis cinerea to identify an antifungal synergist for tebuconazole. Among the 4,006 microbial extracts screened in this study, the culture extract from Schizophyllum commune displayed the most enhanced activity with a sub-lethal dosage of tebuconazole, and the active ingredient was identified as schizostatin. In combination with 5 ㎍/ml tebuconazole, schizostatin (1 ㎍/ml) showed disease control efficacy against gray mold on tomato leaf similar to that achieved with 20 ㎍/ml tebuconazole treatment alone. Interestingly, schizostatin showed demethylation inhibitor (DMI)-specific synergistic interactions in the crossed-paper strip assay using commercial fungicides. In a checkerboard assay with schizostatin and DMIs, the fractional inhibitory concentration values were 0.0938-0.375. To assess the molecular mechanisms underlying this synergism, the transcription levels of the ergosterol biosynthetic genes were observed in response to DMIs, schizostatin, and their mixtures. Treatment with DMIs increased the erg11 (the target gene of DMI fungicides) expression level 15.4-56.6-fold. However, treatment with a mixture of schizostatin and DMIs evidently reverted erg11 transcription levels to the pre-DMI treatment levels. These results show the potential of schizostatin as a natural antifungal synergist that can reduce the dose of DMIs applied in the field without compromising the disease control efficacy of the fungicides.

• 농업과학연구
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• 제48권4호
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• pp.655-668
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• 2021

The present study was conducted to investigate the effects of the supplementation of Achyranthes japonica extract (AJE) on overall performance levels with different nutrition concentrations in the diets of finishing pigs. Here, 140 finishing pigs with initial body weights of 50.18 ± 2.37 kg were used in a ten-week trial involving a 2 × 2 factorial design in two phases with the following factors: diet types with different nutrition concentrations (Positive control [PC] vs. Negative control [NC]) and 0 or 0.05% AJE supplementation to NC and PC diets. The PC diet was a basal diet, whereas the NC diet consisted of a 5% and 7% crude protein (CP) reduced basal diet during phase 1 (1 - 35 days) and phase 2 (36 - 70 days), respectively. A significant effect (p < 0.05) on the gain-to-feed ratio (G : F) was observed with interaction effects between the diets and AJE supplementation. However, during phase 1 and in all periods, the pigs fed the PC and NC diets with average daily feed intake (ADFI) tended to decrease compared to those fed diets with AJE. A significant effect (p = 0.0380) of E. coli was observed in pigs fed the PC and NC diets compared to AJE supplementation in phase 2 of the experiment. The backfat thickness (BFT) tended to decrease and the lean meat percentage (LMP) was significantly improved in phase 2 for pigs fed the PC and NC diets. In summary, BFT and LMP showed beneficial effects and fecal microbiota of E. coli counts were positively affected when pigs were fed diets with different nutrient concentrations.

• Animal Bioscience
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• 제36권6호
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• pp.962-972
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• 2023

Objective: This study determined the effects of dietary treatments and castration on meat quality, fatty acids (FAs) profiles, and volatile compounds in Korean native black goats (KNBG, Capra hircus coreanae), including the relationship between the population of rumen microbiomes and meat FA profiles. Methods: Twenty-four KNBG (48.6±1.4 kg) were randomly allocated to one of four treatments arranged into a 2×2 factorial structure. The factors were dietary forage to concentrate ratio (high forage [HF, 80:20] and low forage [LF, 20:80]), and a castration treatment (castration [CA] vs non-castration [NCA]). Results: Among meat quality traits, the CA group exhibited a higher percentage of crude fat and water holding capacity (p<0.05). The profiles of the saturated fatty acid (SFA) in meat sample derived from CA KNBG showed a significantly lower percentage compared to NCA individuals, due to the lower proportion of C14:0 and C18:0. Feeding a high-forage diet to KNBG increased the formation of C18:1n7, C18:3n3, C20:1n9, C22:4n6 in meat, and polyunsaturated fatty acid (PUFA) profiles (p<0.05). Consequently, the n6:n3 ratio declined (p<0.05). There was an interaction between dietary treatment and castration for formation of C20:5n3 (p<0.05), while C18:1n9, C22:6n3, monounsaturated fatty acid (MUFA) and the MUFA:SFA ratio were influenced by both diet and castration (p<0.05). Nine volatile compounds were identified and were strongly influenced by both dietary treatments, castration (p<0.05), and their interaction. In addition, principal component analysis (PCA) revealed distinctly different odor patterns in the NCA goats fed LF diets. Spearman correlation analysis showed a high correlation between rumen bacteria and meat PUFAs. Conclusion: These results suggest the essential effects of the rumen microbial population for the synthesis of meat FAs and volatile compounds in KNBG meat, where dietary intake and castration also contribute substantially.

• KSBB Journal
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• 제24권4호
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• pp.403-409
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• 2009

본 연구에서는 H2AX의 생리학적인 기능 및 분자세포 생물학적 기전 해석에 대한 보다 명확한 정보를 제시하고자, H2AX 관련 단백질들을 literature review 및 생물정보학적인 기술을 이용하여 최적의 결합 단백질체를 40개를 예측하곤 이들 가운데 상호작용 가능성이 높은 BRCA1와 BARD1 단백질을 선별하여 in vitro 결합실험을 통해 이를 증명하였다. 이들 두 가지의 유전자를 발굴하여, 클로닝하였다. 클로닝된 유전자를 이용하여 두 가지 단백질을 발현 및 정제하였으며, 단백질들의 자체적인 구조에 의한 결합능력을 판단하기 위해 in vitro binding assay법을 실시하였다. 단백질의 구조적 안정과 비특이적 결합을 억제하는 detergent만이 포함된 상태에서, 구조학적 및 물리학적 상호 결합의 유무를 판정할 수 있게 하였으며, BRCA1과 BARD1은 모두 H2AX에 결합함을 확인하였다. 이런 실험결과를 바탕으로 각각의 단백질에 대해 H2AX와의 최적 결합 부위를 알아내기 위해 각 유전자의 domain을 생물정보학적으로 분석하였다. 이에 RING domain, NES, NLS 및 BRCT domain에 해당하는 유전자 부분을 새로 클로닝하여, 다시 in vitro 결합실험 및 실험결과에 대한 literature review를 통한 분석을 실시한 결과, H2AX는 BRCA1의 NLS, BARD1의 BRCT domain 부분과 결합하는 것을 확인하였다. H2AX에 대한 BRCA1과 BARD1과의 결합은 DNA repair에 있어 BRCA1의 NLS와 BARD1의 BRCT domain을 통해 H2AX foci의 관련 세포 신호전달 기전에 중요한 역할을 하여 전체적으로 genomic stability에 영향을 미칠 가능성이 농후할 것으로 사료된다.

• 한국식품위생안전성학회지
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• 제31권6호
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• pp.451-457
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• 2016

본 연구는 수출 딸기 중 병원성 E. coli와 Salmonella spp.를 제어하기 위하여 이산화염소 가스 농도, 상대습도, 시간에 따른 이산화염소 가스의 미생물 저감효과를 조사하였다. 병원성 E. coli, salmonella spp.를 접종한 딸기에 이산화염소 가스 농도(10, 20, 30, 40, 50 ppmv), 상대습도(50, 70, 90%), 처리시간(0, 5, 10, 20, 30분)에 대한 삼요인 실험을 하였다. 그 결과, 각 처리 조건 간의 상호작용이 나타났으며 미생물 저감효과는 상대습도가 가장 높은 조건인 90%에서 이산화염소 가스 농도와 처리시간의 값이 증가할수록 높아지는 경향이 있었다. 상대습도 90%, 이산화염소 가스 농도 50 ppmv에서 처리시간에 따른 미생물 저감화 효과는 5분 동안 처리하였을 때 병원성 E. coli와 Salmonella spp.이 각각 0.5, 0.7 log CFU/g 정도 감소하였으나 20분간 처리하였을 때는 각각 2.07과 2.28 log CFU/g 정도 감소하였다. 따라서 본 연구는 수출 딸기 중 병원성 E. coli와 Salmonella spp.를 제어하기 위한 최적의 이산화염소가스 처리 조건을 확립한 결과로서 수출 딸기의 미생물 안전성 향상에 기여할 수 있으리라 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제31권12호
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• pp.1930-1938
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• 2018

Objective: The present study attempted to determine safe and sufficient growth promoters in poultry feeding. Methods: A total of 520 seven-day-old quail chicks were randomly allotted to eight treatment groups in a $4{\times}2$ factorial design experiment to evaluate the effect of different levels of humic acid (HA) and black cumin (BC) seed and their interactions on growth, carcass traits, gut microbes, and blood chemistry of growing quails. Quails were randomly distributed into 8 groups in a $4{\times}2$ factorial design, included 4 HA levels (0, 0.75, 1.5, and 2.25 g/kg diet) and 2 BC levels (0 or 5 g/ kg diet). Results: Increasing HA level associated with a gradual increase in final weight, feed intake and body weight gain along with an improvement in feed conversion ratio. Dietary addition of 5 g BC powder/kg diet gave similar results. The highest level of HA (2.25 g/kg diet) recorded the best values of carcass weight, breast yield, intestinal length, and intestinal weight comparing with the control and other HA levels. Total viable microbial counts decreased (p<0.05) with increasing levels of HA except the intermediate level (1.5 g/kg diet). The concentration of serum cholesterol and low density lipoprotein (excluding that 0.75 g HA) decreased (p<0.05) and high density lipoprotein increased (p = 0.034) along with increasing HA level. The interaction between the $2.25g\;HA{\times}5g$ gave the best results regarding most studied parameters. Conclusion: These findings indicated that HA combined with BC could be used as effective growth promoters, with the recommended level being 2.25 g HA+5 g BC/kg of quail diet.

• Asian-Australasian Journal of Animal Sciences
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• 제32권7호
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• pp.988-995
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• 2019

Objective: This study was conducted to estimate the temperature and microbial changes of corn silages during aerobic exposure. Methods: Kwangpyeongok (KW) and Pioneer 1543 (PI) corn hybrids were harvested at 29.7% of dry matter and chopped to 3 to 5 cm lengths. Homo (Lactobacillus plantarum; LP) or hetero (Lactobacillus buchneri; LB) fermentative inoculants at $1.2{\times}10^5$ colony forming unit/g of fresh forage was applied to the chopped corn forage which was then ensiled in quadruplicate with a $2{\times}2$ (hybrid${\times}$inoculant) treatment arrangement for 100 days. After the silo was opened, silage was sub-sampled for analysis of chemical compositions, in vitro digestibility, and fermentation indices. The fresh silage was continued to determine aerobic exposure qualities by recorded temperature and microbial changes. Results: The KW silages had higher (p<0.01) in vitro digestibilities of dry matter and neutral detergent fiber than those of PI silages. Silages applied with LB had higher (p<0.001) acetate concentration, but lower (p<0.01) lactate concentration and lactate to acetate ratio than those of LP silages. The interaction effect among hybrid and inoculant was detected in acetate production (p = 0.008), aerobic stability (p = 0.006), and lactic acid bacteria count (p = 0.048). The yeast was lower (p = 0.018) in LB silages than that in LP silages. During the aerobic exposure, PI silages showed higher (p<0.05) temperature and mold than KW silages, while LP silages had higher (p<0.05) lactic acid bacteria and yeast than LB silages. Conclusion: The results indicated that the changes of silage temperature during aerobic exposure seems mainly affected by mold growth, while applied LB only enhanced aerobic stability of PI silages.

• IMMUNE NETWORK
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• 제21권4호
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• pp.25.1-25.16
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• 2021

Asthma is a heterogeneous disease whose development is shaped by a variety of environmental and genetic factors. While several recent studies suggest that microbial dysbiosis in the gut may promote asthma, little is known about the relationship between the recently discovered lung microbiome and asthma. Innate lymphoid cells (ILCs) have also been shown recently to participate in asthma. To investigate the relationship between the lung microbiome, ILCs, and asthma, we recruited 23 healthy controls (HC), 42 patients with non-severe asthma, and 32 patients with severe asthma. Flow cytometry analysis showed severe asthma associated with fewer natural cytotoxicity receptor (NCR)⁺ILC3s in the lung. Similar changes in other ILC subsets, macrophages, and monocytes were not observed. The asthma patients did not differ from the HC in terms of the alpha and beta-diversity of the lung and gut microbiomes. However, lung function correlated positively with both NCR⁺ILC3 frequencies and microbial diversity in the lung. Sputum NCR⁺ILC3 frequencies correlated positively with lung microbiome diversity in the HC, but this relationship was inversed in severe asthma. Together, these data suggest that airway NCR⁺ILC3s may contribute to a healthy commensal diversity and normal lung function.

• Journal of Microbiology and Biotechnology
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• 제28권5호
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• pp.831-838
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• 2018

Trophic interactions of introduced biocontrol fungi with soil animals can be a key determinant in the fungal proliferation and activity. This study investigated the trophic interaction of an introduced biocontrol fungus with soil nematodes. The biocontrol fungus Trichoderma harzianum ThzID1-M3 and the fungivorous nematode Aphelenchoides sp. (10 per gram of soil) were added to nonsterile soil, and microbial populations were monitored for 40 days. Similar results were obtained when the experiment was duplicated. ThzID1-M3 stimulated the population growth of indigenous nematodes (p < 0.05), regardless of whether Aphelenchoides sp. was added. Without ThzID1-M3, indigenous nematodes did not increase in number and the added Aphelenchoides sp. nematodes almost disappeared by day 10. With ThzID1-M3, population growth of nematodes was rapid between 5 and 10 days after treatment. ThzID1-M3 biomass peaked on day 5, dropped at day 10, and then almost disappeared at day 20, which was not influenced by the addition of nematodes. In contrast, a large quantity of ThzID1-M3 hyphae were present in a heat-treated soil in which nematodes were eliminated. Total fungal biomass in all treatments peaked on day 5 and subsequently decreased. Addition of nematodes increased the total fungal biomass (p < 0.05), but ThzID1-M3 addition did not affect the fungal biomass. Hyphae of total fungi when homogenously distributed did not support the nematode population growth; however, hyphae of the introduced fungus did when densely localized. The results suggest that soil fungivorous nematodes are an important constraint on the hyphal proliferation of fungal agents introduced into natural soils.

• 한국가금학회지
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• 제34권1호
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• pp.77-83
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• 2007

Poultry products including meat and eggs constitute a major protein source in the American diet and disease-causing pathogens represent major challenges to the poultry industry. More than 95% of pathogens enter the host through the mucosal surfaces of the respiratory, digestive and reproductive tracts and over the past few decades, the two main mechanisms used to control diseases have been the use of vaccines and antibiotics. However, in the poultry industry, there are mounting concerns over the ability of current vaccines to adequately protect against emerging hyper-virulent strains of pathogens and a lack of suitable, cost effective adjuvants. Thorough investigation of the immunogenetic responses involved in host-pathogen interactions will lead to the development of new and effective strategies for improving poultry health, food safety and the economic viability of the US poultry industry. In this paper, I describe the development of immunogenomic and proteomic tools to fundamentally determine and characterize the immunological mechanisms of the avian host to economically significant mucosal pathogens such as Eimeria. Recent completion of poultry genome sequencing and the development of several tissue-specific cDNA libraries in chickens are facilitating the rapid application of functional immunogenomics in the poultry disease research. Furthermore, research involving functional genomics, immunology and bioinformatics is providing novel insights into the processes of disease and immunity to microbial pathogens at mucosal surfaces. In this presentation, a new strategy of global gene expression using avian macrophage (AMM) to characterize the multiple pathways related to the variable immune responses of the host to Eimeria is described. This functional immunogenomics approach will increase current understanding of how mucosal immunity to infectious agents operates, and how it may be enhanced to enable the rational development of new and effective strategies against coccidiosis and other mucosal pathogens.