• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.149-152
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• 2011

To improve the soil condition for no-tillage organic pepper cultivation, four different green manure crops were cultivated. Fertilizer supply was depended on the biomass of the cultivated green manure crops, nitrogen supplies were 314kg in Vicia villosa and 341kg $ha^{-1}$ in Vicia angustifolia. In the microbial community analyzed by phospholipid fatty acid (PLFA) method, soil microbe populations were different among the green manure crops and fungi group was increased at Vicia angustifloia and Vicia villosa. The biological ratio indexes of fatty acids in the soils, the ratio of Gram-negative to Gram-positive bacterial PLFA and Ratio of aerobes to anaerobes were high at Vicia hirsute and Vicia tetrasperma suggesting the enrich of the aerobic conditions. The ratio of saturated to unsaturated fatty acids increased at Vicia angustifloia and Vicia villosa suggesting anaerobic conditions. Abundant biomass and uncomposted organic matter, the ratio of fungi to bacteria was increased at Vicia angustifloia and Vicia villosa.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.162-167
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• 2015

매년 여름철 피서지 1순위로 손꼽히는 해수욕장은 해양레포츠의 발달과 관광사업의 촉진으로 수많은 관광객들이 방문하고 있다. 하지만 우리나라 대부분의 해수욕장에서는 건전한 해수욕을 위한 수질안전지표 설정이 매우 미흡한 편이며 오염수준 또한 심각하다. 이에 강원도 강릉시 경포해수욕장을 대상지역으로 2012년 7월 17일부터 9월 4일까지 매주 화요일 오전에 채취한 시료로부터 병원성 수질지표인 장구균과 대장균, 총대장균군의 오염도를 분석하였다. 시료는 경포해수욕장 오리바위 배후부터 연안방향을 따라 200m 간격으로 3지점과 이안방향을 따라 백사장(dry beach), 포말대(swash zone), 유영층(swimming zone)의 3지점에서 총 9개를 채취하였다. 기온, 강우, 장소 등의 해안 환경 변화에 따른 병원균 증식 유리조건 및 인자들간의 상관성을 분석한 결과 백사장에서는 총대장균군, 포말대에서는 장구균, 유영층에서는 대장균의 농도가 가장 높았다. 또한 주간 누적 강우량과 평균 기온에 따라 시료채취 지점마다의 상관성에서는 백사장은 강우량과 정비례, 기온과는 반비례, 포말대와 유영층은 강우량과 반비례, 기온과는 정비례의 관계를 보였다. 백사장과 해수층인 포말대, 백사장과 유영층 각각은 반비례 관계를 보였지만 미비한 수준이었으며 포말대와 유영층간의 상관성은 약 90%의 매우 높은 수치를 띄었다. 본 연구는 건전한 수계 레크레이션 문화의 수질 안전지표 설정을 위해 해수욕장의 대표 관광명소 중 하나인 경포해수욕장을 대상으로 병원성 수질 지표들의 증식 유리 조건 및 확산특성 예측에 목적이 있다. 나아가 본 과정은 해변을 찾는 관광객들의 수질 안전 정보 제공 및 체계적인 가이드라인 제시로도 가치 있을 것으로 기대된다.

• Animal cells and systems
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• v.14 no.3
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• pp.225-236
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• 2010

We compared the composition of phospholipid fatty acids (PLFA) to assess the microbial community structure in the soil and rhizosphere community of non-transgenic watermelons and transgenic watermelons in Miryang farmlands in Korea during the spring and summer of 2005. The PLFA data were seasonally examined for the number of PLFA to determine whether there is any difference in the microbial community in soils from two types of watermelons, non-transgenic and transgenic. We identified 78 PLFAs from the rhizosphere samples of the two types of watermelons. We found eight different PLFAs for the type of plants and sixteen PLFAs for the interaction of plant type and season. The PLFA data were analyzed by analysis of variance separated by plant type (P<0.0085), season (P<0.0154), and the plant type${\times}$season interaction (P<0.1595). Non-parametric multidimensional scaling (NMS showed a small apparent difference but multi-response permutation procedures (MRPP) confirmed that there was no difference in microbial community structure for soils of both plant types. Conclusively, there was no significant adverse effect of transgenic watermelon on bacterial and fungal relative abundance as measured by PLFA. We could reject our hypothesis that there might be an adverse effect from transgenic watermelon with our statistical results. Therefore, we can suggest the use of this PLFA methodology to examine the adverse effects of transgenic plants on the soil microbial community.

• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.197-204
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• 2019

BACKGROUND: Living modified microorganisms (LMMs) have been focused in two very different aspects of positive and negative effects on ecology and human health. As a model experiment, wild type and a foreign origin gene-harboring modified E. coli strains were subjected to comparison of their metabolomes and potential effects on soil microbiota in the laboratory sets. This study assumes the unintentional release of LMMs and tries to suggest potential effects on the soil microbiota even at minimal settings. METHODS AND RESULTS: Metabolomes from the wild type and LM E. coli were analyzed by NMR and the profiles were compared. In the laboratory soil experiments, the two types of E. coli were added to the soils and monitored for the bacterial community compositions. Those metabolomic profiles did not show significant differences. The microbial community structures from the time series soil DNAs for both the sets using wild type and LMO also did not indicate significant changes, but minor by the addition of foreign organisms regardless of wild or LMO. CONCLUSION: Even if the recombinant microorganism (LMO) is released into the soil environment, the survival of microorganisms in the environment would be one of the major factors for the transfers of foreign genes to other organisms and diffusion into the soil environment.

• Journal of Environmental Science International
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• v.30 no.12
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• pp.1015-1025
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• 2021

Our research work aimed to evaluate cover crop effects of winter rye on soil characteristics, soil conservation, and yield productivities on potato fields with 15% slope during a fallowed period. There were two controls of bared field without any cultivation and conventional potato cultivation without winter rye. Potato cultivation increased soil pH, organic matter, available phosphate, and exchangeable cation regardless of cover crop cultivation. Sub-soil, particularly, all components of soil chemical properties showed higher value in winter rye cultivation than conventional cultivation. Higher soil density was observed on cover crop cultivation than conventional cultivation resulting from root residues of the cover crop both topsoil and subsoil. Cover crop residues positively affected plant growth and reduced the amount of soil erosion by holding the soil. Although severe soil erosion was seen in conventional cultivation, winter rye cultivation declined soil erosion by 47% during the fallow period on potato slope fields. Distinct soil bacterial communities were detected among treatments and some OTU(Operational Taxonomic Unit)s showed significantly higher abundance in winter rye treatment. Total yield and commercial rate demonstrated no significant differences while higher tuber phosphate, K⁺, and Mg²⁺ contents were observed in winter rye cultivation.

• Journal of Conservation Science
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• v.38 no.1
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• pp.64-71
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• 2022

Many investigations have been conducted on the biological damage and environmental conditions necessary to preserve the Janggyeong Panjeon and Daejanggyeongpan (woodblocks). We performed a survey on the concentration and diversity of airborne fungi in the Janggyeong Panjeon and compared them with the results of a survey from 2012. The temperature of the Beopbojeon building was slightly lower, while the relative humidity was higher than those found at the Sudarajang building. The concentration of airborne fungi in the Beopbojeon was 1.44-fold that of the Sudarajang. It was confirmed that the concentration and diversity of airborne fungi in the Janggyeong Panjeon differed depending on the sampling site. In total, 23 fungal genera were identified from the air samples, and 11 fungal and 1 bacterial genera were identified from the surface of the woodblocks. Among these, only five types of fungi were commonly distributed in the indoor air and surface of the Daejanggyeongpan; however, 58.3% of the fungi identified on the surface of the woodblocks were not observed in the in the air samples. The surface-dwelling fungi may accumulate dust to form microbial communities over time.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.715-723
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• 2023

Microbial biofilms are resilient, immune-evasive, often antibiotic-resistant health challenges, and increasingly the target for research into novel therapeutic strategies. We evaluated the effects of a nutraceutical enzyme and botanical blend (NEBB) on established biofilm. Five microbial strains with known implications in chronic human illnesses were tested: Candida albicans, Staphylococcus aureus, Staphylococcus simulans (coagulase-negative, penicillin-resistant), Borrelia burgdorferi, and Pseudomonas aeruginosa. The strains were allowed to form biofilm in vitro. Biofilm cultures were treated with NEBB containing enzymes targeted at lipids, proteins, and sugars, also containing the mucolytic compound N-acetyl cysteine, along with antimicrobial extracts from cranberry, berberine, rosemary, and peppermint. The post-treatment biofilm mass was evaluated by crystal-violet staining, and metabolic activity was measured using the MTT assay. Average biofilm mass and metabolic activity for NEBB-treated biofilms were compared to the average of untreated control cultures. Treatment of established biofilm with NEBB resulted in biofilm-disruption, involving significant reductions in biofilm mass and metabolic activity for Candida and both Staphylococcus species. For B. burgdorferi, we observed reduced biofilm mass, but the remaining residual biofilm showed a mild increase in metabolic activity, suggesting a shift from metabolically quiescent, treatment-resistant persister forms of B. burgdorferi to a more active form, potentially more recognizable by the host immune system. For P. aeruginosa, low doses of NEBB significantly reduced biofilm mass and metabolic activity while higher doses of NEBB increased biofilm mass and metabolic activity. The results suggest that targeted nutraceutical support may help disrupt biofilm communities, offering new facets for integrative combinational treatment strategies.

• Journal of Microbiology and Biotechnology
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• v.33 no.11
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• pp.1495-1505
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• 2023

The western honeybee Apis mellifera L., a vital crop pollinator and producer of honey and royal jelly, faces numerous threats including diseases, chemicals, and mite infestations, causing widespread concern. While extensive research has explored the link between gut microbiota and their hosts. However, the impact of Varroa destructor infestation remains understudied. In this study, we employed massive parallel amplicon sequencing assays to examine the diversity and structure of gut microbial communities in adult bee groups, comparing healthy (NG) and Varroa-infested (VG) samples. Additionally, we analyzed Varroa-infested hives to assess the whole body of larvae. Our results indicated a notable prevalence of the genus Bombella in larvae and the genera Gillamella, unidentified Lactobacillaceae, and Snodgrassella in adult bees. However, no statistically significant difference was observed between NG and VG. Furthermore, our PICRUSt analysis demonstrated distinct KEGG classification patterns between larval and adult bee groups, with larvae displaying a higher abundance of genes involved in cofactor and vitamin production. Notably, despite the complex nature of the honeybee bacterial community, methanogens were found to be present in low abundance in the honeybee microbiota.

• Food Science of Animal Resources
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• v.44 no.2
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• pp.390-407
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• 2024

Kuflu cheese, a popular variety of traditional Turkish mold-ripened cheeses, is characterized by its semi-hard texture and blue-green color. It is important to elucidate the microbiota of Kuflu cheese produced from raw milk to standardize and sustain its sensory properties. This study aimed to examine the bacteria, yeasts, and filamentous mold communities in Kuflu cheese using high-throughput amplicon sequencing based on 16S and ITS2 regions. Lactococcus, Streptococcus, and Staphylococcus were the most dominant bacterial genera while Bifidobacterium genus was found to be remarkably high in some Kuflu cheese samples. Penicillium genus dominated the filamentous mold biota while the yeasts with the highest relative abundances were detected as Debaryomyces, Pichia, and Candida. The genera Virgibacillus and Paraliobacillus, which were not previously reported for mold-ripened cheeses, were detected at high relative abundances in some Kuflu cheese samples. None of the genera that include important food pathogens like Salmonella, Campylobacter, Listeria were detected in the samples. This is the first experiment in which the microbiota of Kuflu cheeses were evaluated with a metagenomic approach. This study provided an opportunity to evaluate Kuflu cheese, which was previously examined for fungal composition, in terms of both pathogenic and beneficial bacteria.

• Journal of Soil and Groundwater Environment
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• v.11 no.2
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• pp.38-44
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• 2006

Two sulfur-based column reactors inoculated with a bacterial consortium containing autotrophic denitrifiers were operated for 100 and 500 days, respectively and nitrate removal efficiency and the adaptation of microbial communities in the columns were monitored with column depths and time. For better understanding the adaptation phenomenon, molecular techniques including 16S rDNA sequencing and DGGE analysis were employed. Although both columns showed about 99% of nitrate removal efficiency heterotrophic denitrifiers such as Cenibacterium arsenioxidans and Geothrix fermentans were found to a significant portion at the initial stage of the 100-day reactor operation. However, as operation time increased, an autotrophic denitrifier Thiobacillus denitrificans became a dominant bacterial species throughout the column. A similar trend was also observed in the 500-day column. In addition, nitrate removal efficiencies were different with column depths and thus bacterial species with different metabolic activities were found at the corresponding depths. Especially, T. denitrificans was successfully adapted and colonized at the bottom parts of the columns where most nitrate was reduced.