• 한국토양비료학회지
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• 제47권6호
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• pp.451-456
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• 2014

Organic amendment practices can influence diversity and activities of soil microorganisms. There is a need to investigate this impact compared with other types of materials. This study was carried out to evaluate the long term effects of chemical and organic fertilizer on soil microbial community in upland field. During the last 11 years green manure, rice straw compost, rapeseed cake, pig mature compost, NPK, and NPK + pig mature compost were treated in upland soil. Organic fertilizer treatment found with high bacterial colony forming units (CFUs) as compared to chemical and without fertilizer treatment. There was no significant difference in the actinomycetes and fungal population. The average well color development (AWCD) value was the highest in green manure and, the lowest in without fertilizer treatment. Analyses based on the denaturing gradient gel electrophoresis (DGGE) profile showed that rice straw compost and pig mature compost had a similar banding pattern while rapeseed cake, NPK, NPK + pig mature compost and without fertilizer treatment were clustered in another cluster and clearly distinguished from green manure treatment. Bacterial diversity can be highly increased by the application of organic fertilizer while chemical fertilizer had less impact. It can be concluded that green manure had a beneficial impact on soil microbial flora, while, the use of chemical fertilizer could affect the soil bacterial communities adversely.

• 한국균학회지
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• 제44권2호
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• pp.82-86
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• 2016

충북 제천의 폐광산 지역의 근권 토양과 인근 일반 산림 지역의 근권 토양을 수집하여 토양 내의 수지상균근균(AMF)의 다양성 및 군집 구조를 확인하였다. 폐광산 지역의 근권 토양은 Acaulospora mellea, 일반 산림 지역의 토양은 Ambispora leptoticha가 우점하는 것을 확인하였다. 군집 구조를 분석한 결과, 폐광산 지역의 근권 토양에서 일반 산림 지역의 근권 토양보다 AMF 포자 수가 많은 것을 확인하였고, 두 지역의 종 다양성 지수에는 유의미한 차이가 존재하지 않았으나 일반 산림 토양의 군집 내 유사도 지수가 폐광산 지역의 근권 토양보다 유의미한 수준으로 높게 나타나는 것을 알 수 있었다. 따라서 본 연구는 교란의 차이에 의해 AMF의 군집이 달라질 수 있음을 보여준다.

• Journal of Microbiology and Biotechnology
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• 제24권8호
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• pp.1088-1095
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• 2014

A systematic investigation was performed on the bacterial, Bacillus, fungal, and yeast communities of the three types of Daqu (mechanically prepared, manually prepared, and mixed prepared) used in Baiyunbian Company by reconditioning PCR-denaturing gradient gel electrophoresis (PCR-DGGE). The DGGE results showed that the microbes in the three types of Daqu were mainly thermotolerant and thermophilic microbes, and the most dominant bacterial species were Bacillus and Virgibacillus, followed by Lactobacillus and Trichococcus. Furthermore, the dominant fungi were found to be molds, such as Rasamsonia, Penicillium, Aspergillus, and Monascus, and the dominant yeasts were Saccharomyces cerevisiae, Saccharomycopsis fibuligera, Pichia anomala, and Debaryomyces hansenii. In general, the three types of Daqu showed slight differences in microbial communities, and the Shannon indexes (H') of the manually prepared and mechanically prepared Daqu were similar. The results suggest that mechanically prepared Daqu can replace manually prepared Daqu in liquor production, and this research provides useful information for liquor production and process improvement.

• Asian Pacific Journal of Cancer Prevention
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• 제16권8호
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• pp.3403-3406
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• 2015

Background: Skin biopsy is the method to assist clinicians to make definite dermatological diagnosis which further helps in holistic management. Skin cancers are relatively rare clinical diagnosis in developing countries like Nepal, but the prevalence is on rise. Objectives: To investigate the profile of skin biopsies and frequencies and pattern of skin cancers in a tertiary care centre of Western Nepal. Materials and Methods: The materials consisted of 434 biopsies (1.37%) out of 31,450 OPD visits performed in the Department of Dermatology, Manipal Teaching Hospital, Pokhara, Nepal, during the period of Dec 2011-Nov 2014. Data were collected and analyzed using SPSS-16 with reference to incidence, age, sex, race and clinical and histopathological features. Results: The commonest disorders observed in biopsies were papulosquamous lesions, skin tuberculosis of different types, benign skin tumors, leprosy, collagen and fungal diseases. Viral diseases were rarely seen, probably due to straight forward clinical diagnosis. Dermatological malignancies accounted for 55/434 (12.67%) of biopsies. Skin disorders in general were commoner in females 280/434 (64%), including malignancies 32/55(58.2%). Mean age of patients with skin cancer was 54.5 years. Facilities for proper laboratory investigation of dermatological disorders will improve the quality of life. Conclusions: The most prevalent lesion in skin biopsies was papulosquamous disorders followed by skin tuberculosis of different types. Dermatological malignancy constituted 55/434 (12.67%) cases. The prevalence of skin malignancy is on rise in Nepalese society probably due to increase in life expectancy and better diagnostic services.

• 식물병연구
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• 제21권3호
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• pp.161-179
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• 2015

식물은 다양한 병원성 미생물에 대하여 효과적인 방어 기제를 발전시켜 왔다. 최근 유전체와 다중 오믹스 기술의 발전은 우리에게 미생물 인자에 의한 식물 면역을 폭넓게 이해할 수 있는 단초를 제공해 주었다. 하지만 아직까지는 이러한 기술을 병 방제 전략에 이용한 적은 많지 않다. 그래서 본 리뷰에서 식물 면역의 기본 개념을 소개하고 최근 얻어진 결과들을 소개하였다. 덧붙여 이미 논문에서 발표된 진균, 세균, 바이러스 유래 결정인자에 의한 생물적 방제 가능한 방법에 대해 기술하였다. 특히 미생물 결정인자인 chitin, glucan, LPS/EPS, 미생물분자패턴, 항생제, 식물유사호르몬, AHLs, harpin, 비타민, 휘발성물질에 대한 결과를 자세하게 기술하였다. 이 리뷰를 통하여 많은 과학자들과 농민들이 미생물 결정인자 기반의 생물적 방제에 대한 지식이 폭넓어지고, 다양한 미생물 결정 인자가 앞으로 농업현장의 종합적인 병방제 전략의 하나로 자리매김하기를 바란다.

• Journal of Microbiology and Biotechnology
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• 제20권12호
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• pp.1614-1623
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• 2010

Bacteria were isolated from roots of sugarcane varieties grown in the fields of Punjab. They were identified by using API20E/NE bacterial identification kits and from sequences of 16S rRNA and amplicons of the cpn60 gene. The majority of bacteria were found to belong to the genera of Enterobacter, Pseudomonas, and Klebsiella, but members of genera Azospirillum, Rhizobium, Rahnella, Delftia, Caulobacter, Pannonibacter, Xanthomonas, and Stenotrophomonas were also found. The community, however, was dominated by members of the Pseudomonadaceae and Enterobacteriaceae, as representatives of these genera were found in samples from every variety and location examined. All isolates were tested for the presence of five enzymes and seven factors known to be associated with plant growth promotion. Ten isolates showed lipase activity and eight were positive for protease activity. Cellulase, chitinase, and pectinase were not detected in any strain. Nine strains showed nitrogen fixing ability (acetylene reduction assay) and 26 were capable of solubilizing phosphate. In the presence of 100 mg/l tryptophan, all strains except one produced indole acetic acid in the growth medium. All isolates were positive for ACC deaminase activity. Six strains produced homoserine lactones and three produced HCN and hexamate type siderophores. One isolate was capable of inhibiting the growth of 24 pathogenic fungal strains of Colletotrichum, Fusarium, Pythium, and Rhizoctonia spp. In tests of their abilities to grow under a range of temperature, pH, and NaCl concentrations, all isolates grew well on plates with 3% NaCl and most of them grew well at 4 to $41^{\circ}C$ and at pH 11.

• Journal of Ginseng Research
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• 제45권4호
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• pp.519-526
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• 2021

Background: This study aimed to investigate the effect of cold plasma treatment on the improvement of seed germination and surface sterilization of ginseng seeds. Methods: Dehisced ginseng (Panax ginseng) seeds were exposed to dielectric barrier discharge (DBD) plasma operated in argon (Ar) or an argon/oxygen mixture (Ar/O₂), and the resulting germination and surface sterilization were compared with those of an untreated control group. Bacterial and fungal detection assays were performed for plasma-treated ginseng seeds after serial dilution of surface-washed suspensions. The microbial colonies (fungi and bacteria) were classified according to their phenotypical morphologies and identified by molecular analysis. Furthermore, the effect of cold plasma treatment on the in vitro antifungal activity and suppression of Cylindrocarpon destructans in 4-year-old ginseng root discs was investigated. Results: Seeds treated with plasma in Ar or Ar/O₂ exhibited a higher germination rate (%) compared with the untreated controls. Furthermore, the plasma treatment exhibited bactericidal and fungicidal effects on the seed surface, and the latter effect was stronger than the former. In addition, plasma treatment exhibited in vitro antifungal activity against C. destructans and reduced the disease severity (%) of root rot in 4-year-old ginseng root discs. The results demonstrate the stimulatory effect of plasma treatment on seed germination, surface sterilization, and root rot disease suppression in ginseng. Conclusion: The results of this study indicate that the cold plasma treatment can suppress the microbial community on the seed surface root rot in ginseng.

• Mycobiology
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• 제50권5호
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• pp.389-398
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• 2022

Endophytic fungi are promising sources for the production of podophyllotoxin-an important anticancer compound, replacing depleted medical plants. In this study, the endophytes associated with Dysosma difformis-an ethnomedicinal plant species were isolated to explore novel sources of podophyllotoxin. Fifty-three endophytic fungi were isolated and identified by morphological observation and ITS-based rDNA sequencing, assigning them to 27 genera in 3 divisions. Fusarium was found the most prevalent genus with a colonization frequency of 11.11%, followed by Trametes (9.26%) and Penicillium (7.41%). Phylogenetic trees were constructed for the endophytic fungi community in two collection sites, Ha Giang and Lai Chau, revealing the adaptation of the species to the specific tissues and habitats. Cytotoxic activity of endophytic fungal extracts was investigated on cancer cell lines such as SK-LU-1, HL-60, and HepG2, demonstrating strong anti-cancer activity of six isolates belonging to Penicillium, Trametes, Purpureocillium, Aspergillus, and Ganoderma with IC₅₀ value of lower than 10 ㎍/mL. The presence of podophyllotoxin was indicated in Penicillium, Trametes, Aspergillus and for the first time in Purpureocillium and Ganoderma via high-performance liquid chromatography, which implied them as a potential source of this anticancer compound.

• Journal of Microbiology and Biotechnology
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• 제23권5호
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• pp.644-651
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• 2013

The fermented manure derivative known as Preparation 500 is traditionally used as a field spray in biodynamic agriculture for maintaining and increasing soil fertility. This work aimed at characterizing the product from a microbiological standpoint and at assaying its bioactive properties. The approach involved molecular taxonomical characterization of the culturable microbial community; ARISA fingerprints of the total bacteria and fungal communities; chemical elemental macronutrient analysis via a combustion analyzer; activity assays for six key enzymes; bioassays for bacterial quorum sensing and chitolipooligosaccharide production; and plant hormone-like activity. The material was found to harbor a bacterial community of $2.38{\times}10^8$ CFU/g dw dominated by Gram-positives with minor instances of Actinobacteria and Gammaproteobacteria. ARISA showed a coherence of bacterial assemblages in different preparation lots of the same year in spite of geographic origin. Enzymatic activities showed elevated values of ${\beta}$-glucosidase, alkaline phosphatase, chitinase, and esterase. The preparation had no quorum sensing-detectable signal, and no rhizobial nod gene-inducing properties, but displayed a strong auxin-like effect on plants. Enzymatic analyses indicated a bioactive potential in the fertility and nutrient cycling contexts. The IAA activity and microbial degradation products qualify for a possible activity as soil biostimulants. Quantitative details and possible modes of action are discussed.

• 한국토양비료학회지
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• 제41권2호
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• pp.118-125
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• 2008

다비작물이면서 재배기간이 긴 고추 재배지에서 당년의 효과를 기대하고 시용되는 유기물은 각 지역마다 사용되는 종류가 다양함으로 이들이 토양 미생물 상에 미치는 효과를 검토할 필요가 있다. 본 연구에서는 우리나라에서 쉽게 구할 수 있는 수피, 우분, 왕겨, 볏짚과 이것으로 만든 퇴비가 토양의 화학적 미생물적 특성에 미치는 효과를 분석하였다. 퇴비가 pH를 포함한 토양 화학적 특성 변화에 가장 효과적이었고 수피는 유기물 증가에 기여하였다. 인지질 지방산의 토양 생물학적 지표 분석에서 퇴비는 방선균과 균근균 밀도 증가에 효과적이었으며, y19:0/18:1w7c와 단불포화/포화 지방산의 비율도 증가시켰다. 수피는 곰팡이 밀도 증가에 효과적이었고, 왕겨와 볏짚은 퇴비와 수피 만큼의 토양 미생물상 군락에 미치는 효과는 적었으나 왕겨가 볏짚 보다 컸다. 그리고 전체 미생물 상을 관찰하기 위하여 PLFA와 Biolog EcoPlate 성적을 주요인 분석으로 살펴 본 결과 수피가 두 가지 방법 모두에서 다른 처리 특히 퇴비 처리구와는 구별 되는 미생물 군을 형성함을 보여주었다. 따라서퇴비와 수피가 토양의 화학적 특성과 미생물상 변화에 가장 큰 영향을 미쳤고, 특히 토양 미생물상에 미치는 두 유기 토양 개량제의 영향은 방향이 크게 다르므로 신선 수피의 토양 개량제로의 이용은 더 많은검토가 필요한 것으로 사료된다.