• Archives of Pharmacal Research
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• 제19권3호
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• pp.178-182
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• 1996

Using superoxide dismutase (SOD)-deficient mutants of Saccharomyces cerevisiae, the oxidative stresses induced by 0.1 mM of copper ion $(Cu^{++})$ was studied. In aerobic culture condition, yeasts lacking MnSOD (mitochondrial SOD) showed more significant growth retardation than CuZnSOD (cytoplasmic SOD)-deficient yeasts. However, not so big differences in growth pattern of those mutants compared withwild type were observed under anaerobic condition. It was found that, under aerobic condition, the supplementation of 0.1 mM copper ioh:(Cu") into culture medium caused the remarkable increase of CuZnSOD but not so significant change in MnSOD. It was also observed that catalase activities appeared to be relatively high in the presence of copper ion in spite of the remarkable reduction of glutathion peroxidase in CuZnSOD-deficient yeasts, but the slight increments of catalase and glutathion peroxidase were detected in MnSOD-deficient strains. It implies that the lack of cytoplasmic SOD could be compensated mainly by catalase. However, these phenomena resulted in the significantincrease of cellular lipid peroxides content in CuZnSOD-deficient yeasts and the slight increment of lipid peroxides in MNSOD-deficient cells. In anaerobic cultivation supplementing copper ion, the cellular enzyme activities of catalase and glutathion peroxidase in SOD-deficient yeasts were slightly increased without any significant changes of lipid peroxides in cell membrane. It suggests that a little amount of free radicals generated by copper ion under anaerobic condition could be sufficiently overcome by catalase as well as glutathion peroxidase.dase.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.277-280
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• 2000

수소 생산량은 기질로부터 생산될 수 있는 수소의 분자수와 균주간의 특성에 의해서 좌우된다. 광합성 세균에 의한 수소 가스 생산은 유기물질 및 물을 전자 공여체로 하여 광합성에 의해 생산되는 것으로 알려져 있다. 이론적으로 수소생산량은 glucose 한 분자로부터 12분자의 수소가스가 생산된다.

• 한국치위생학회지
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• 제4권2호
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• pp.153-163
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• 2004

There are normal inhabitants doing medically useful functions in the body. There are many kinds of bacteria performing specific functions in the oral cavity. Two strains of lactic acid bacteria were isolated from normal inhabitants of children 's oral cavity, which inhibited the the production of halitosis by anaerobic bacteria. The authors identified the isolates by the lest using API 50 CHL medium kit. 1. Two isolates were Gram-positive bacilli and produced hydrogen peroxide. 2. The optical density was 1.286 in the supernatant of Fusobacterium nucleatum after vortexing for 30 minutes, whereas in the supernatant of combined Fusobacterium nucleatum and each isolate, they were reduced to 0.628 and 0.497, which the percentages of coaggregation between them were 29.4% and 57.8%, respectively. 3. The optical density of Fusobacterium nucleatum precipitate was 1.794 in the culture media containing cysteine and $FeSO_4$, being reduced to 1.144 and 0.915 in the coaggregated precipitates of Fusobacterium nucleatum and each isolate. 4. The optical density of Porphyromonas gingivalis precipitate was 1.932 in the culture media, being reduced to 1.170 and 1.266 in the coaggregated precipitates of Porphyromonas gingivalis and each isolate. 5. When two isolates were tested with API 50 CHL medium kit, those were identified as Lactobaciallius salivarius and Lactobacillus delbrueckii subsp. lactis.

• Asian-Australasian Journal of Animal Sciences
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• 제17권6호
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• pp.820-824
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• 2004

The study was to see the effect of administration of ruminal fungi on feed intake, growth rate, rumen fermentation and nutrient digestion of calves (Tharparkar$\times$Holstein-Friesian, average age: 10 months, average body weight: 130 kg). The 6 calves in first group were fed a mixture consisted of 50% wheat straw and 50% concentrate (Maize 62%, Groundnut cake 35%, Mineral mix. 2% and Common salt 1%) along with 1 kg green oats $animal^{-1}$ $day^{-1}$ while second group calves were fed the above-mentioned diet in addition to a dose of 160 ml ($10^{6}$ CFU/ml) fungal culture $calf^{-1}$ $week^{-1}$. The average dry matter intake per day was slightly lowered in fungal fed calves yet feed conversion ratio was higher. The average daily weight gain was significantly higher (15.37%) in fungal administered group as compared to control. The nutrient digestibility was increased for crude fibre, NDF and ADF with fungal administration. Digestible energy value of straw-based diet in terms of percent TDN also increased. The pH and $NH_{3}$-N were lower whereas TVFA, total-N, TCA-N and number of zoospores were higher in rumen liquor in fungal administered group.

• 미생물학회지
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• 제11권2호
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• pp.101-106
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• 1973

microwave oven의 배지 처리에의 이용에 고나한 실험에서 다음 결론을 얻었다. 1)배지 융해에 이용함으로써 시간을 단축하고, 푸로판 불꽃 사용시의 실내 공기 오염을 막을 수 있었다, 2)혐기성 배지에서의 공기 저게는 wire barsket에 넣은 시험관을 물이 든 beaker에서 가열하므로써 끓어 넘는것을 막을 수 있었다. 3)배지 중의 E.coli 살균효과는 불꽃처리의 경우와 비슷하였으며 고압멸균을 대치할 수는 없을 것으로 판단되었다, 저자들의 실험실에서는 매일 5~6종의 배지를 만들기 위해 융해하며, 혐기성 세균동정을 위해 40~50개의 반유동 배지에서 공기를 제거하는바 이를 위해 지난 수개월간 microwave oven을 이용하고 있고 편리함을 경험하고 있다.

• 한국미생물·생명공학회지
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• 제18권1호
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• pp.71-75
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• 1990

B.longum TK-100 및 L.acidophilus TK-2070으로 혼합배양한 culture로 제조한 요쿠르트는 냉장상태에서도 산생성이 되었느데 이는 B.longum TK-100에 의한 것보다는 대수기의 L.acidophilus TK-2070에 의하여 거의 생성되었다. B.longum TK-100은 편성 혐기조건 뿐만아니라 통성혐기조건에서도 생육이 좋은 것으로 나타냈다. 또한, B.longum과 L.acidophilus는 냉장보존 중인 요쿠르트 내에서도 생존도가 양호하므로 발효유의 제조, 개발에 혼합 starter로서의 이용이 가능하다고 하겠다. 한편 aniline bule 0.1가 함유된 RCAM plate상에 나타난 B.longum TK-100의 colony는 직경이 약 2mm의 광택있는 회배색의 중심에 청색을 나타내었고, L.acidophilus TK-2070의 coiny는 직경이 약 1mm 의 회배색을 나타내어 쉽게 분별할 수 있다.

• Journal of Korean Dental Science
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• 제16권1호
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• pp.35-46
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• 2023

Purpose: Culture-based methods for microbiological diagnosis and antibiotic susceptibility tests have limitations in the management of orofacial infections. We aimed to profile pus microbiota and identify antibiotic resistance genes (ARGs) using a culture-independent approach. Materials and Methods: Genomic DNA samples extracted from the pus specimens of two patients with orofacial abscesses were subjected to shotgun sequencing on the NovaSeq system. Taxonomic profiling and prediction of ARGs were performed directly from the metagenomic raw reads. Result: Taxonomic profiling revealed obligate anaerobic polymicrobial communities associated with infections of odontogenic origins: the microbial community of Patient 1 consisted of one predominant species (Prevotella oris 74.6%) with 27 minor species, while the sample from Patient 2 contained 3 abundant species (Porphyromonas endodontalis 33.0%; P. oris 31.6%; and Prevotella koreensis 13.4%) with five minor species. A total of 150 and 136 putative ARGs were predicted in the metagenome of each pus sample. The coverage of most predicted ARGs was less than 10%, and only the CfxA2 gene identified in Patient 1 was covered 100%. ARG analysis of the seven assembled genome/metagenome datasets of P. oris revealed that strain C735 carried the CfxA2 gene. Conclusion: A metagenomics-based approach is useful to profile predominantly anaerobic polymicrobial communities but needs further verification for reliable ARG detection.

• Journal of Microbiology and Biotechnology
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• 제17권3호
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• pp.428-437
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• 2007

The potential for humic substances to serve as terminal electron acceptors in microbial respiration and the effects of humic substances on microbial azoreduction were investigated. The dissimilatory azoreducing microorganism Shewanella decolorationis S12 was able to conserve energy to support growth from electron transport to humics coupled to the oxidation of various organic substances or $H_2$. Batch experiments suggested that when the concentration of anthraquinone-2-sulfonate (AQS), a humics analog, was lower than 3 mmol/l, azoreduction of strain S12 was accelerated under anaerobic condition. However, there was obvious inhibition to azoreduction when the concentration of the AQS was higher than 5 mmol/l. Another humics analog, anthraquinone-2-sulfonate (AQDS), could still prominently accelerate azoreduction, even when the concentration was up to 12 mmol/l, but the rate of acceleration gradually decreased with the increasing concentration of the AQDS. Toxic experiments revealed that AQS can inhibit growth of strain S12 if the concentration past a critical one, but AQDS had no effect on the metabolism and growth of strain S12 although the concentration was up to 20 mmol/l. These results demonstrated that a low concentration of humic substances not only could serve as the terminal electron acceptors for conserving energy for growth, but also act as redox mediator shuttling electrons for the anaerobic azoreduction by S. decolorationis S12. However, a high concentration of humic substances could inhibit the bacterial azoreduction, resulting on the one hand from the toxic effect on cell metabolism and growth, and on the other hand from competion with azo dyes for electrons as electron acceptor.

• 대한수의학회지
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• 제33권1호
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• pp.61-69
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• 1993

In order to search for new antibiotics from anaerobic bacteria, a large number of samples from domestic soil were collected and processed by apropriate methods. A potential strain, Streptococcus sp. An-21-1, was found to produce antimicrobial compounds. The Results were as follows; 1. During fermentation, the bacteria grew rapidly up to 20hr, thereafter entered the death phase. The optimal temperature and pH for the bacterial growth were $37^{\circ}C$ and pH 7.0, respectively. 2. Antibiotics were purified from culture broth by solvent extraction, silica gel column chromatography and Sepadex L.H 20 column. 3. Physicochemical properties of Ap-1 and Ap-2 were similar ; Their melting points were between $234-237^{\circ}C$. Color reactions of ninhydrin, 2,7-dichlorofluorescein, 4-dimethylaminobenzaldehyde, Dragendroffs reagent and 20% $H_2SO_4$, were positive. Therefore, we assumed that these antibiotics have amine group, immine group, alkaloid, and lipid components. These were stable to heat. UV spectrophotometry showed two peaks at 210 nm and 260 nm. From above results, we assumed these antibiotics are belong to the peptide antibiotic family.

• 공업화학
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• 제32권5호
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• pp.487-496
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• 2021

Microalgae is one of the promising biodiesel feedstock with high growth rates compared to those of terrestrial oil crops. Despite its numerous advantages, biodiesel production from microalgae needs to reduce energy demand and material costs further to go to commercialization. During solvent extraction of microalgal lipids, lipid-extracted algae (LEA) cell residue is generated as an organic solid waste, about 80-85% of original algal biomass, and requires an appropriate recycling or economic disposal. The resulting LEA still contains significant amount of carbohydrates, proteins, N, P, and other micronutrients. This review will focus on recent advancement in the utilization of LEA as: (i) utilization as nutrients or carbon sources for microalgae and other organisms, (ii) anaerobic digestion to produce biogas or co-fermentation to produce CH₄ and H₂, and (iii) conversion to other forms of biofuel through thermochemical degradation processes. Possible mutual benefits in the integration of microalgae cultivation-biodiesel production-resulting LEA with anaerobic digestion and thermochemical conversion are also discussed.