• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.340-342
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• 2005

한천분해 세균은 제주 연안의 해수로부터 분리되어졌다. 균주는 Gram 음성 간균이며, 절대 호기성 세균이다. 균주는 agarase를 생성하여 한천을 분해하는 것으로 관찰되었다. 균주의 생화학적 특성과 16S rRNA 유전자 염기서열 분석한 결과 Agarivorans속으로 동정 되었다. 그래서 Agarivorans sp. JA1이라 명명하였다. agarase의 최적 생산을 위한 agar농도는 0.5%이며, pH, 온도와 NaCl 농도는 각각 pH 7, $25^{\circ}C$ $^{\sim}$ $30^{\circ}C$와 2%였다. 유기태과 무기태는 각각 yeast extract와 $NaNO_3$를 첨가 할 경우 agarase 생성이 가장 좋은 것으로 사료되었다. Agarase의 최적 생산 활성 측정은 DNS법(3,5-dinitrosalicyclic acid procedure)을 이용하여 환원당 값을 산출하였고, 50000(U/L)이상 나왔다.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.777-782
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• 2004

The arylsulfatase gene (astA, 984 bp ORF) from the P. carrageenovora genome was amplified by PCR and subcloned into the pET21a vector. When the constructed plasmid pAST-A1 (6.4 kb) was introduced into E. coli BL21(DE3), the transformant on the LB plate containing IPTG showed a hydrolyzing activity for 4-methylumbelliferyl sulfate and p-nitrophenyl sulfate. The highest arylsulfatase activity (2.1 unit/ml) was obtained at 10 mM IPTG. Most arylsulfatase activity was found in the cell lysate, whereas no significant activity was detected in the culture supernatant. The molecular weight of the recombinant enzyme was estimated to be 33.1 kDa by SDS-PAGE. After the reaction of agar with arylsulfatase for 12 h at $40^{\circ}C$, the gel strength of the agar increased by 2-fold, and 73% of the sulfate in the agar had been removed. This result suggests that arylsulfatase expressed in E. coli could be useful in the production of electrophoretic grade agarose.

• 한국균학회지
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• 제20권4호
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• pp.302-308
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• 1992

Seven genera and 15 species of fungi were isolated from 50 samples of then different steps of dried onion (5 samples of each step) collected from an onion factory in Sohag Governorate, Egypt, and grown on glucose-Czapek's agar (7 genera and 15 species) and 10% NaCl glucose-Czapek's (2 genera and 6 species). The average total counts of fungi were gradually decreased throughout the different steps of drying from 2090 to zero and 152 to zero colonies/g on glucose-Czapek's agar and 10% NaCl glucose-Czapek's agar media, respectively. Aspergillus was the most common genus on the two types of media used. The dominant species were Aspergillus niger, A. flavus, A. terreus, Penicillium chrysogenum and Fusarium of oxysporum on glucose-Czapek's agar and A. terreus and A. niger on 10% NaCl glucose-Czapek's agar. The chloroform extracts of different samples were tested for the presence of mycotoxins using thin layer chromatographic analysis. The results indicated that aflatoxin was present at concentrations decreased throughout the different steps of the drying from step No. 1, onion bulbs, $120\;{\mu}g/kg$; to step No. 8, standard A, $20\;{\mu}g/kg$ while step Nos. 9 & 10 (completely dry powdered onion) were free from aflatoxin. Citrinin was also present in the first three steps at concentrations gradually decreased from 30 to 10 mg/kg.

• Mycobiology
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• 제39권2호
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• pp.85-91
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• 2011

We investigated the effect of nutritional and environmental factors on Ophiocordyceps longissima mycelial growth. The longest colony diameter was observed on Schizophyllum (mushroom) genetics complete medium plus yeast extract, Schizophyllum (mushroom) genetics minimal medium, and Sabouraud dextrose agar (SDA); however, malt-extract yeast-extract agar, SDA plus yeast extract, yeast-extract malt-extract peptone dextrose agar, SDA, oatmeal agar, and potato dextrose agar showed higher mycelia density. A temperature of $25^{\circ}C$ was optimum and 7.0 was the optimum pH for mycelial growth. Colony diameter was similar under light and dark conditions. Maltose and yeast extract showed the highest mycelial growth among carbon and nitrogen sources respectively. The effect of mineral salts was less obvious; however, $K_3PO_4$ showed slightly better growth than that of the other mineral salts tested. Among all nutrition sources tested, complex organic nitrogen sources such as yeast extract, peptone, and tryptone were best for mycelial growth of O. longissima. Ophiocordyceps longissima composite medium, formulated by adding maltose (2% w/v), yeast extract (1% w/v), and $K_3PO_4$ (0.05% w/v) resulted in slightly longer colony diameter. In vitro mycelial O. longissima growth was sustainable and the production of fruiting bodies could be used for commercial purposes in the future.

• 한국식품조리과학회지
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• 제33권1호
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• pp.87-93
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• 2017

Purpose: Rice starch is known not to be suitable to Mook. Its gel is not hard and elastic enough and too sticky. This study investigated the effects of agar, carrageenan, and gelatin addition on low amylose rice flour paste and gel properties for making Mook. Methods: Angemi, low amylose rice, and Goamibyeo, intermediate amylose rice, were dry milled. The properties of Mook were determined by texture profile analysis (TPA), cold storage stability, and sensory acceptance. Results: Addition of agar and carrageenan increased cold paste viscosity, whereas addition of gelatin decreased cold paste viscosity while improving breakdown and setback viscosity. When 30% of gelling agents such as agar, carrageenan, and gelatin were added to low amylose rice, Angemi, Mook-like gels were formed. The hardness, adhesiveness, and springiness of gelling reagent-added Angemi Mook increased, whereas cohesiveness decreased, and fracturability was not observed. The addition of gelling agent decreased lightness and increased yellowness. Angemi Mook added with gelatin showed the best freeze-thaw stability while addition of agar and carrageenan increased syneresis. The carrageenan-added Angemi Mook was equal to Goamibyeo 100% Mook in all sensory acceptance properties without significant difference. Conclusion: Above results suggest that addition of carrageenan and gelatin to low amylose rice can be used to produce Mook with improved physical properties.

• 한국자원식물학회지
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• 제17권1호
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• pp.43-47
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• 2004

기내에서 삽목 배양중인 한라구절초[( Chrysanthemum zawadskii ssp. coreanum(Nakai) Y.N. Lee)]의 잎으로부터 효과적인 식물체 재생을 위한 NAA와 BA농도 및 배지고형물의 효과를 조사하였다. 0.2% Gelite를 고형물로 하였을 때 한라구절초의 잎 재분화에는 BA농도보다는 NAA 농도가 더 영향을 미쳤으며, NAA 농도가 1 mg/L 이상이면 모든 조직 에서 재분화를 보였다. 신초수는 NAA 단용 처리에서 많은 경향이었으며 NAA 1 mg/L 처리시가 가장 양호하였다. 배지고형물로 agar과 gelite를 가지고 재분화 효과를 조사한 결과, gelite 첨가시 잎절편 당 신초수가 많았으며 agar 첨가시에는 잎절편당 신초수가 적은 반면에 신초의 길이가 길게 나타났다. 한라구절초의 잎절편으로부터 재분화에는 MS에 3% sucrose, 0.8% agar와 NAA 1 mg/L를 첨가하여 25 $^{\circ}C$, 2,000 lux 정도에서 배양하는 것이 효과적이었다.

• 한국균학회지
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• 제46권1호
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• pp.9-21
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• 2018

Seven unrecorded species in the phylum Ascomycota, Emericellopsis pallida (KNU16-167), Scedosporium aurantiacum (KNU16-190), Duddingtonia flagrans (KNU16-279), Bionectria rossmaniae (KNU16-309), Exophiala xenobiotica (KNU16-79), Pseudocercosporella fraxini (KNU16-102), and Stachybotrys sansevieriae (KNU16-141), were isolated in 2016 from field soils collected from various locations in Korea. All of the species were identified and described based on morphological characteristics and rDNA internal transcribed spacer sequence data. Morphological features of these fungi were examined on potato dextrose agar, oatmeal agar, malt extract agar, Czapek yeast extract agar, and yeast extract sucrose agar. Full descriptions and illustrations of their morphological characteristics are provided.

• 미생물학회지
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• 제28권3호
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• pp.229-235
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• 1990

평판배지상 세균 colony의 체외 세포 효소활성을 직접 측정할 수 있는 신속하고 정확한 방법에 대하여 기술하였다. 일반적으로 세균의 효소 특성을 살피기 위해서는 단백질, 전분, chitin, tween-80 등과 같은 고분자 물질을 첨가한 선택배지를 사용하고 있으나 그 방법상 여러 가지 문제점이 있다 그러므로 본 연구에서는 형광물질의 일종인 Methvlumbell liferyl(MUF) 기질이 일반적으보 사용되고 있는 천연 고분자 물질고 유사한가를 순수분리세균 균주를 이용하여 실험으로 검증하였다. MUF 기질 분해원리에 기초를 둔 기술한 새로운 방법은 순수 분리 균주는 물론 colony 계수에 사용되는 평판배지상에서도 세균의 체외세포 효소 특성을 정량적으로 측정 가능하게 한다. 본 새로운 방법을 이용하여 담수 생태계와 해양 퇴적토내 종속영양세균의 체외 효소 활성을 측정하여 고찰하였다.

• 한국균학회지
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• 제46권4호
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• pp.383-392
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• 2018

During the study of indigenous fungal communities in soil samples collected from various field soils in Sancheong, Gyeongsangnam-do, Korea in 2017, several species of Aspergillus were discovered. Aspergillus caninus (KNU17-7) was isolated, identified, and described based on the results from macro and micro morphological characteristics and molecular characterization. Morphologically, it was identified using five different growth media: potato dextrose agar, oatmeal agar, yeast extract sucrose agar, czapek yeast extract agar, and malt extract agar. For the molecular identification, sequencing of internal transcribed spacer, ${\beta}-tubulin$, and calmodulin genes was performed. Based on this characterization, our study isolate was identified as Aspergillus caninus. This fungal species has not been officially reported in Korea before, and we report here with its morphological and molecular phylogenetic characterization.

• Nutrition Research and Practice
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• 제12권6호
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• pp.479-485
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• 2018

BACKGROUND/OBJECTIVES: Gelidium amansii (GA) contains plenty of agars and various biological substances, which make them a popular functional food to control body weight in previous studies. Unlike previous studies focused on agar in GA, objectives of this study were to investigate the effects of agar-free GA extract (AfGAE) on preventive and treatment models by using diets-induced obese (DIO) C57BL/6J mice. MATERIALS/METHODS: AfGAE were used to test their effects on the prevention (Exp-1) and treatment (Exp-2) against obesity after pilot study in DIO mice. The weight changes of the body and fat tissues and protein expression related to lipid metabolism and inflammation as well as plasma lipid profile and insulin were detected. RESULTS: Although AfGAE did not prevent long-term DIO, it did increase the levels of anti-inflammatory cytokine production and lipolysis protein. We further evaluated various doses of AfGAE in preventive and treatment models. As a result, our findings suggested that an AfGAE administration as a preventive model might be a better approach to achieve its anti-inflammatory and lipolysis-promoting effects in DIO mice. CONCLUSION: Although future studies to investigate the target materials such as polyphenols in AfGAE are required, the result suggests that GA without agar might be a therapeutic tool to improve health conditions related to inflammation.