• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.275-284
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• 2014

This study was orchestrated with the purpose of uncovering new nutraceutical resources possessing biological activities in the plant kingdom. To fulfill our objective, we analyzed several Chinese plants and selected three possessing powerful anti-oxidative activities. The anti-oxidative and anti-inflammatory effects these three Chinese plants, Malus hupehensis, Ophiorrhiza cantonensis, and Psychotria rubra ethanol extracts were then evaluated. First of all, they possessed potent scavenging activity against 1,1-diphenyl-2-picryl hydrazyl, similar with that of ascorbic acid, used as a positive control. Moreover, they inhibited lipopolysaccharide (LPS)- and hydrogen peroxide-induced reactive oxygen species, in a dose-dependent manner, in RAW 264.7 cells. Also, they induced the expression of an anti-oxidative enzyme, heme oxygenase 1, and its upstream transcription factor, nuclear factor-E2-related factor 2. Furthermore, they suppressed LPS-induced nitric oxide (NO) formation, without cytotoxicity. The inhibition of NO formation was the result of the down regulation of inducible NO synthase (iNOS). The suppression of NO and iNOS by the three extracts might be the result of modulation by the upstream transcription factors, nuclear factor ${\kappa}B$ and activator protein-1. Taken together, these results indicate that these three Chinese plants possess potent anti-oxidative and anti-inflammatory activities. Therefore, they might be utilized as promising materials in the field of nutraceuticals.

• Research in Plant Disease
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• v.30 no.2
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• pp.165-175
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• 2024

The Korean fir tree (Abies koreana), an endemic species of South Korea, is experiencing a severe decline in population due to climate change. Studies on the conservation of Korean fir have been extensive, yet research regarding its correlation with rhizosphere bacterial communities remains scarce, warranting further investigation. In this study, metagenome amplicon sequencing targeting the 16S rRNA V4 region was conducted to examine the presence of specific bacterial communities in Korean fir and to investigate potential differences based on habitat types (rhizosphere of native or cultivated trees, soil of dead trees, and bulk soil) and seasonal variations (April, June, September, November). Here we show that although we could not identify specific taxa highly specifically with Korean fir, the rhizosphere bacterial community in native trees exhibited less variability in response to seasonal changes compared to that in bulk soils. Suggesting the establishment of relatively stable bacterial populations around the Korean fir natural habitat. Further research on other types of rhizosphere and/or microbes is necessary to investigate the distinct relationship of Korean fir with microbial communities.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.5
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• pp.433-438
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• 2003

To select new useful domestic plants with antimicrobial activities, thirty five samples of berry plant were distributed from Plant Diversity Research Center in Korea Research Institute of Bioscience and Biotechnology. Their extracts with methanol were tested against Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, Listeria monocytogenes by paper disc method. The methanol extracts from Viburnum dilatatum, Viburnum erosum, Aralia continentalis, Camellia japonica, Acer trumcatam, Arasaema takesimense and Rhysocarpus intermedius were effective against S. aureus and the results were as follows: Viburnum erosum 6.5 mm, Viburnum dilatatum and Aralia continentalis 7.0 mm, Rhysocarpus intermedius 8.0 mm, Acer trumcatum 9.0 mm, Camellia japonica and Arisaema takesimense 9.5 mm. And only the methanol extract from Camellia japonica was effective against L. monocytogenes, 7.0 mm. Antimicrobial activities of E. coli and S. typhymurium were not detected. The minimum inhibitory concentration(MIC) of berry of Camellia japonica was examined as 1,250 $\mu\textrm{g}$/mL against S. aureus and as 1,250∼2,500 $\mu\textrm{g}$/mL against L. monocytogenes.

• Korean Journal of Organic Agriculture
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• v.13 no.4
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• pp.389-400
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• 2005

This study was conducted to investigate into the ecological environments and the soil microflora of purple-bracted plantain lily (Hosta longipes Matsumura) for wild vgetables. Native soil textures of purple-bracted plantain lily were in the order of sandy loam (SL) > loam (L) > clay loam (CL). pH in soil was relatively acid by 4.8, electric conductivity was 0.08mS/cm, and organic matter content was 0.08g/kg. CEC was measured by $100.8cmol^{(+)}kg^{-1}$ and available phosphate was 103.4mg/kg. Contents of exchangeable cations in terms of potassium, calcium, and magnesium were measured by $0.33cmol^{(+)}kg^{-1},\;2.26cmol^{(+)}kg^{-1},\;and\;0.87cmol^{(+)}kg^{-1}$, etc. Diurnal changes in the air temperature of the natives were 15 to $20^{\circ}C$, that temperature differential was relatively little compared with that in open field by 15 to $30^{\circ}C$. Relative humidity in the natives were much more humid by 60 to 80% compared with that in open feld by 35 to 85%. Light intensity in the natives and the open field at ten o'clock were $2,300{\mu}mol/m^2/sec.\;and\;1,750{\mu}mol/m^2/sec.$ Total number of soil microorganisms were $8.4{\times}10^7\;c.f.u./g$. Mycorrhizal spore densities over $500{\mu}m,\;355{\sim}500{\mu}m,\;251{\sim}354{\mu}m,\;107{\sim}250{\mu}m\;and\;45{\sim}106{\mu}m$ were 0.8, 1.3, 2.1, 38.1, and 110.0 respectively. Mycorrhizal root infections by vesicle and hyphae were 17% and 6%. However, arbuscules in the roots were not shown.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1999.04a
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• pp.29-52
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• 1999

본 연구는 강원도 고랭지에서 자생되는 산채류를 이용하여 총질소함량을 기준으로 소맥대신 이들 산채류를 일정비율로 대체하여 더덕 및 산채혼합 간장을 제조하여 그 특성을 조사하였으며 또한, 감마선조사 또는 블랜칭처리가 참나물 즙액의 선도유지연장에 미치는 영향을 조사하였다. 제조된 간장의 총 질소함량은 일반적으로 산채 대체량의 증가에 따라 증가하였다. 숙성 4개월 후의 무기질 함량에 있어 더덕 20% 대체간장은 Ca, K 함량이 각각 1.3배, 1.5배의 증가율을 나타내었으며, 산채 혼합 10% 대체간장도 Ca 함량이 1.5배 증가하였다. 대체량 별로 아미노산 함량 변화를 살펴보면 더덕간장 10% 대체군의 경우 threonine과 aspartic acid가, 산채 혼합 10% 대체군은 tyrosine과 arginine이 높은 증가율을 나타내었다. Rec assay system을 이용한 항돌연변이 시험에서, 더덕간장은 10%와 20% 대체군이, 산채혼합 간장은 7%와 10% 대체군이 다른 시료에 비해 높은 항돌연변이성을 나타내었다. 관능검사 결과, 전체적 기호도에 있어 더덕간장은 7% 대체군, 산채혼합 간장은 5% 대체군이 가장 우수하였다. 미생물의 생육변화는 감마선 조사를 하였을 때 두처리구 모두 0.5 kGy 조사에서도 무처리구에 비하여 현저한 생육감소를 나타내었으며 감마선 처리된 녹즙을 저온에서 저장하였을 때는 미생물의 생육억제효과가 높았으나 상온에서는 감마선 효과가 매우 감소함을 나타내었다. 색도변화는 블랜칭한 녹즙이 블랜칭하지 않은 녹즙보다 색깔이 훨씬 선명하고 맑은 녹색을 띄었으며 시간이 경과함에 따라 감마선 조사구가 시간이 경과함에 따라 무처리구에 비하여 L값, a값 및 b값이 훨씬 적게 변화함을 나타내었다. 비타민 C의 변화는 블랜칭 처리한 녹즙의 비타민 C의 함량변화는 블랜칭 처리를 하지않은 녹즙보다 적었으며 감마선 처리구와 거의 차이가 없었으며 온도가 낮을수록 두 처리구 모두 비타민 C의 손실율이 적게 나타났다. 감마선을 조사하였을 때 블랜칭하지않은 녹즙에서는 무처리구와 비교하여 볼 때 밝기, 풀냄새, 쓴맛, 신선감 및 수용성에서 차이가 없었으며 블랜칭한 녹즙에서는 무처리구가 감마선처리구에 비하여 풀냄새와 쓴맛이 증가하였고 신선감과 수용성이 감소되었다.

• The Korean Journal of Mycology
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• v.49 no.2
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• pp.211-242
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• 2021

Indigenous yeasts in Korea have been actively studied since 1910 in light of various fields, including environment, food fermentation, brewing, and medicine. However, a complete list of indigenous yeast species has not been addressed or reported. In this study, a comprehensive analysis of the literature including yeast isolation from Korean materials and the strains preserved at culture collections was performed. The results of this study indicate the following: i) there are 128 genera and 681 species (including 26 variants) of yeast reported in Korea, ii) the reported species were trimmed into 142 genera and 500 species (including 9 variants), iii) among which only 166 species were registered in the National Species List of Korea (2020). Therefore, follow-up studies are required to register more indigenous yeast species in the National Species List of Korea.

• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.66-72
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• 2007

Yam has been recognized as healthy food due to its various biological activities, such as anti-obesity, antimicrobial, anticancer and immune-stimulation activities. In this study, antibacterial activities of 800 more natural plant extracts against yam-putrefactive psychrotrophic bacterium, Pseudomonas rhodesiae YAM-12, were evaluated to select a natural preservative, which is useful to long-term storage of yam and fresh-cut production. Finally, the clove oil was selected, and applied for the production of yam fresh-cut. The 1% of clove oil treated fresh-cut showed minor color changes during 31 days storage at $4^{\circ}C$ and the microbial growth was not detected. When the artificially contaminated fresh cut by dipping with P. rhodesiae YAM-12 suspension for 3 min was treated 1% clove oil, the microbial growth was identified to $10^4$ CFU/g from $10^3$ CFU/g with minor color changes. Whereas, treatment of sterilized water, or 100 ppm NaOCl into artificially contaminated fresh cut showed severe putrefaction $(10^8\;CFU/g)$ and color changes. Considering the previous reports that clove oil has antimicrobial, antioxidation, and antithrombosis activity, the use of clove oil into the yam fresh cut will provide market safety and consumer acceptability by prevention of microbial putrefaction and its biological activity.

• Microbiology and Biotechnology Letters
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• v.49 no.1
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• pp.111-119
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• 2021

A bacterial strain isolated from a Malva verticillata leaf was identified as Bacillus velezensis MV2 based on the 16S rRNA sequencing results. Complete genome sequencing revealed that B. velezensis MV2 possessed a single 4,191,702-bp contig with 45.57% GC content. Generally, Bacillus spp. are known to produce diverse antimicrobial compounds including bacteriocins, polyketides, and non-ribosomal peptides. Antimicrobial compounds in the B. velezensis MV2 were extracted from culture supernatants using hydrophobic interaction chromatography. The crude extracts showed antimicrobial activity against both gram-positive bacteria and gram-negative bacteria; however, they were more effective against gram-positive bacteria. The extracts also showed antifungal activity against phytopathogenic fungi such as Fusarium fujikuroi and F. graminearum. In time-kill assays, these antimicrobial compounds showed bactericidal activity against Bacillus cereus, used as indicator strain. To predict the type of antimicrobial compounds produced by this strain, we used the antiSMASH algorithm. Forty-seven secondary metabolites were predicted to be synthesized in MV2, and among them, fourteen were identified with a similarity of 80% or more with those previously identified. Based on the antimicrobial properties, the antimicrobial compounds may be nonribosomal peptides or polyketides. These compounds possess the potential to be used as biopesticides in the food and agricultural industry as an alternative to antibiotics.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.300-306
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• 2002

141 methanol extracts from 125 plant species which populate in Korea were screened for antimicrobial activity against various food-borne pathogens and food spoilage microorganisms. Those plants were selected from 3 different plant groups: traditional herbs, edible plants and flowers. The methanol extracts were tested by using the disk diffusion assay against five bacteria: Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Enterobacter aerogenes, Escherichia coli. From the evaluation of the inhibition zone diameter of microbial growth, the most significant antimicrobial activity against Bacillus subtilis, Staphylococcus auresus, Pseudomonas aeruginosa, Enterobacter aerogenes, Escherichia coli was observed from the extract of Schizandra chinensis (Turcz.) Baill., Rheum officinale Baill., Schizandra chinensis (Turcz.) Baill., Koelreuteria paniculata Lax and Crataegus pinnatifida Bunge, respectively. The extract from many plants - Koelreuteria paniculata Lax, Chaenomeles sinensis Koehne, Scutellaria bacicalensis Georgi, Castanea crenata Sieb. et Zucc., Rosa centifolia L., Allium fistulosum L. var. giganteum Makino, Crataegus pinnatifida Bunge, Schizandra chinensis (Turcz.) Baill., Lonicera japonica - showed antimicrobial activity all four tested bacteria.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.148.2-149
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• 2003

고사리(Pteridium aquilinum)는 참고사리과에 속하는 다년생 양치식물로서 온대지방과 열대지방에 널리 분포되어 있으며 이른봄부터 늦가을까지 산야에 생육되며 북극 남아프리카 지역을 제외한 전세계에 광범위하게 자생하고 있다. 고사리는 봄철에 어린싹을 삶아 물에 담구었다가 먹거나 건조시켜 저장해서 이용하는데 현재 유통되고 있는 건고사리는 수확, 건조 및 저장 중에 비위생적인 관리 등에 의해 미생물의 증식 및 해충의 발생 등으로 품질이 크게 저하되어 저장상 많은 어려움을 안고 있다. 방사선에 의한 식품 저장은 이미 그 건전성과 경제적 타당성이 인정되어 세계 여러나라에서 실용화되고 있으며 특히 건조 채소류의 살균, 살충을 위한 방사선의 이용은 제품의 재수화성을 증가시킨다는 보고도 있다. 따라서, 본 실험에서는 국내에서 소비량이 비교적 많은 건고사리에 Co-60 감마선을 조사하여 건고사리 조리전 필수 조리조작인 불림조작 조건에 따른 복원력 및 물리적 특성을 분석하였다. 건고사리에 조사선량을 0, 3, 5, 7kGy로 달리 하여 조사하였고 침지온도, 침지 시간에 따른 수분함량, 부피, 수화 복원력, 색상, 조직감을 측정하였다. 실험결과, 조사선량이 높을수록 부피 증가율, 수화 복원력은 대조구에 비해 유의적으로 증가하였다. 조직감 중 경도는 침지온도, 시간 및 조사선량이 증가할수록 감소하여, 건고사리를 불리기 위해 드는 시간이 단축되어 에너지 절감의 효과가 있는 것으로 파악되었다.