• 한국미생물·생명공학회지
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• 제8권2호
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• pp.93-102
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• 1980

서울 근교의 토양과 나무잎을 시료로 체취하여 여기서 gluconic acid의 생산성이 우수한 Aspergillus SP. 로 동정된 잠정적으로 KUF-O4로 명명한 균주를 분리하여 여러가지 배양조건으로 gluconic acid 생산성을 연구하였다. 그 실험 결과들을 요약하면 다음과 같다. 1. 배양시간은 30시간에서 40시간 사이가 적합하였으며 40시간이 경과되면 오히려 생산량이 감소하였다. 2. CaCo$_3$는 10g/100ml의 Glucose를 배지에서 3g/100ml 이상이 첨가되어야 양호하였다. 3. 탄소원으로서는 Glucose의 chain이 갈수록 불량하였으며 glucose가 가장 적합하였다. 4. 질소원으로서는 NH$_4$태 질소가 NO$_3$태나 유기태 질소보다 우수한 결과이었으며 그 농도는 (NH$_4$)$_2$SO$_4$로서 0.1g/1,000m1 내지 0.5g/1,000ml이었다. 5. 무기염으로서는 KH$_2$PO$_4$와 MgSO$_4$를 소량 첨가시키는 편이 생산성을 향상시켰으며 그 농도는 전자는 0.1g/1,000ml이고 후자는 0.5g/l,000ml 이었다. 한편 미량첨가물로서 Vitamin와 amino acid는 별다른 효과를 인지할 수 없었다. 이상과 같이 KUF-04 균주를 잘 이용한다면 앞으로 gluconic acid를 공업적으로 생산할 수 있을 것으로 기대된다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2009년도 추계학술대회 및 정기총회
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• pp.3-13
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• 2009

90 wild Agaricus strains from China, including 44 Agaricus bisporus strains identified preliminarily by isozyme electrophoresis, were studied by the techniques of SRAP and ISSR. 18 special SRAP bands and 12 special ISSR bands were analyzed, the strains were clustered and a demdrogram was obtained. The results showed that the strains were divided into 2 groups, wild A. bisporus group and the other Agaricus group. It is similar to the result of isozyme electrophoresis. 41 wild A. bisporus strains from Sichuan and Tibet were divided into 4 groups based on their growing places, suggesting the regionally difference of the strains to be quite obvious. Some white wild A. bisporus strains from Xinjiang and Tibet had special patterns, resulting in lower coefficient values with other wild A. bisporus strains. The biological characteristics of three wild A. bisporus strains were analyzed, and the results showed: 1. The wild strains grew slowly on PDA medium with weak appressed mycelia, and grew normally in kernel or fermented cottonseed shell substrate. 2. They grew faster than control strain As2796 under lower temperature of $16^{\circ}C$, and higher temperature of $32^{\circ}C$, with optimum growing temperature of $20-24^{\circ}C$, which was $4^{\circ}C$ lower than that of control strain. 3. In the cultivation with manure compost via twice fermentation, the mycelia grew normally in compost and quite slowly in casing soil, and the fruitbodies occurred less and late with easily opening and low production. 4. The fruitbody was off-white with flat and scaled cap, long stipe and dark gill. The bisporus basidia occupied 70-80% and trisporus basidia 20-30% of the total basidia. 5. Heterokaryotic monospore isolates could fruit in cultivation, and the homokaryotic isolates could cross with those derived from overseas wild A.bisporus strains. 6. The electrophoresis phenotype of isozymes such as esterase etc. belonged to high production type (H type). 7. The RAPD patterns made much difference from those of high production, good quality or hybrid strains, which indicated that the wild strains produce a new kind of RAPD type.

• KSBB Journal
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• 제21권6호
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• pp.422-427
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• 2006

Helicobacter pylori에 대하여 항균효과가 가장 높은 Fomitopsis pinicola를 동정하고 저해물질의 성질에 관한 연구를 수행한 결과 다음과 같은 결론이 얻어졌다. H. pylori에 대한 항균력이 가장크게 나타난 네팔에서 채취한 F. pinicola의 동정결과는 F. pinicola AY854083로 밝혀졌다. F. pinicola의 균사체는 액상배양을 시작한 후 5일이 경과하면서 H. pylori에 대한 항균력이 나타났으며 8일 이후부터 가장 높았다. 그러나 균사체 추출물에서는 항균력이 나타나지 않았다. F. pinicola 균사체 8일 배양액의 H. pylori에 대한 최소억제 농도는 $0.25\;mg/m{\ell}$ 이었고, 배양액의 낮은 pH (pH 2.0)가 H. pylori의 생육억제에 영향을 주지만 중화를 하여도 H. pylori에 대한 항균력은 유지되었다. F. pinicola 균사체 8일 배양액을 DEAE-sephadex A-25 LC로 분리하여 Fp-P1, Fp-P2 및 Fp-P3를 얻었으며 H. pylori에 대한 항균력은 Fp-P1에서만 나타났다. Fp-P1을 thin layer chromatography로 분리하였으며 H. pylori에 대한 항균력은 $R_{f}$ 값이 0.67인 Fp-T3에서만 나타났다. F. pinicola 균사체 8일 배양액, Fp-P1, Fp-T3를 HPLC의 Waters symmetry $300\;C_{18}\;5\;{\mu}m$ column ($3.9{\times}150\;mm$)으로 분리한 결과 Fp-T3에서 단일 peak만 남았으며 이것이 H. pylori에 대한 항균력을 확인하였다. H. pylori에 대한 항균력을 나타내는 F. pinicola 균사체 배양액에서 분리 정제한 물질은 BioLC 분석과 TLC 발색결과로써 아미노기를 포함한 당으로 사료된다.

• 생명과학회지
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• 제21권8호
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• pp.1083-1093
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• 2011

왕겨를 기질로 사용하여 carboxymethylcellualse (CMCase)를 생산하는 미생물을 해수에서 분리하였으며 16S rDNA의 염기서열을 분석하여 동정한 결과, Bacillus lichemiformis로 확인되었다. CMCase를 생산하기 위한 최적의 탄소원과 질소원은 왕겨와 암모니움 나이트레이트이었다. 통계학적인 방법인 response surface method (RSM)을 사용하여 CMCase를 생산하기 위한 조건을 최적화하였다. 통계학적인 분석 결과, 왕겨가 균체의 생육에 미치는 영향이 가장 높았으며, 왕겨와 배지의 초기 pH가 CMCase 생산에 미치는 영향이 높았다. Design Expert Software를 사용하여 결과를 분석한 결과, 균체의 생장에 최적인 조건은 48.7 g/l 왕겨, 1.8 g/l 암모니움 나이트레이트, 배지의 초기 pH 6.8 및 배양온도 35.7$^{\circ}C$이었으나, CMCase의 생산에 최적인 조건은 43.2 g/l 왕겨, 1.1 g/l 암모니움 나이트레이트, 배지의 초기 pH 6.8 및 배양온도 35.7$^{\circ}C$이었다. 최적화된 조건에서 왕겨를 기질로 사용하여 B. lincheniformis LBH-52가 생산하는 CMCase는 79.6 U/ml이었다. 본 연구를 통하여 왕겨와 암모니움 나이트레이트를 CMCase를 생산하는 기질로 개발하였으며, 해수에서 분리한 미생물을 사용하여 생산기간을 3일로 단축하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제31권9호
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• pp.1464-1473
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• 2018

Objective: To describe in-depth sequencing, the bacterial community diversity and its succession during ensiling of whole-plant maize and subsequent exposure to air. Methods: The microbial community dynamics of fermented whole-plant maize for 60 days (sampled on day 5, 10, 20, 40, 60) and subsequent aerobic exposure (sampled on day 63 after exposure to air for 3 days) were explored using Illumina Miseq sequence platform. Results: A total of 227,220 effective reads were obtained. At the genus level, there were 12 genera with relative abundance >1%, Lactobacillus, Klebsiella, Sporolactobacillus, Norank-c-cyanobacteria, Pantoea, Pediococcus, Rahnella, Sphingomonas, Serratia, Chryseobacterium, Sphingobacterium, and Lactococcus. Lactobacillus consistently dominated the bacterial communities with relative abundance from 49.56% to 64.17% during the ensiling process. Klebsiella was also an important succession bacterium with a decrease tendency from 15.20% to 6.41% during the ensiling process. The genus Sporolactobacillus appeared in late-ensiling stages with 7.70% abundance on day 40 and 5.32% on day 60. After aerobic exposure, the Lactobacillus decreased its abundance from 63.2% on day 60 to 45.03% on d 63, and Klebsiella from 5.51% to 5.64%, while Sporolactobacillus greatly increased its abundance to 28.15%. These bacterial genera belong to 5 phyla: Firmicutes (relative abundance: 56.38% to 78.43%) was dominant, others were Proteobacteria, Bacteroidetes, Cyanobacteria, and Actinobacteria. The bacterial communities clearly clustered into early-ensiling (d 5), medium-ensiling (d 10, d 20), late-ensiling (d 40, d 60), and aerobic exposure (d 63) clusters, with early- and late-ensiling communities more like each other than to the aerobic exposure communities. Conclusion: High-throughput sequencing based on 16S rRNA genes proved to be a useful method to explore bacterial communities of silage. The results indicated that the bacterial communities varied during fermentation and more dramatically during aerobic exposure. The study is valuable for understanding the mechanism of population change and the relationship between bacteria and ensilage characteristics.

• 한국수산과학회지
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• 제22권5호
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• pp.363-369
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• 1989

산업적으로 속성젓갈을 대량 생산하기 위하여, 우선 시중 젓갈에서 단백질분해력이 강한 균주 4 종을 분리하여 속성 분해정도와 분해 생성물의 풍미를 비교 검토한 결과 B. subtilis p-4 및 B. licheniformis p-5 균이 가장 양호하였으며, 이들 균주와 그 pretense의 특성은 다음과 같다. pH 7.0, $40^{\circ}C$ 식염$1\%$ 농도에서 균체 및 조효소 활성이 가장 양호하였으며, 이때의 비증식속도는 p-4 균 및 p-5 균이 각각 0.48/hr, 0.49/hr이었고, 최대 효소활성 농도는 p-4 는 30시간 후 335n mole-Tyr/min.ml, p-5는 28시간 후 300n mo1e-Tyr/min.ml이였다. 그리고 sephadex G-100 겔 여과에 의한 효소 정제도는 조효소에 비해 비활성이 p-4 및 p-5 균 protease의 경우 각각 25.4배, 8.6배씩 증가하였으며, pH 7.0, $50^{\circ}C$에서 활성이 가장 높았다. 또한 겔여과에 의한 분자량은 p-4가 18,000, p-5 protease가 30,000이었고, 저해제의 효과에서는 두 Protease 모두 $Ni^{2+},\;Cu^{2+}$ 이온과 EDTA, o-phenanthroline에 의해 강하게 활성이 소실되는 것으로 보아 metal chelator sensitive neutral protease에 속하는 것으로 추정되었다.

• 한국응용과학기술학회지
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• 제32권4호
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• pp.758-766
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• 2015

Dextran is a generic term for a bacterial exopolysaccharide synthesized from sucrose and composed of chains of D-glucose units connected by ${\alpha}$-1,6-linkages by using dextransucrases. Dextran could be used as vicosifying, stabilizing, emulsifying, gelling, bulking, dietary fiber, prebiotics, and water holding agents. We isolated new strain capable of producing dextran from Korean traditional kimchi and identified as Leuconostoc sp. strain JYY4. Batch fermentation was conducted in bioreactor with a working volume of 3 L. The media was MMY and 15% (w/v) sucrose. Mineral medium consisted of $3.0g\;KH_2PO_4$, $0.01g\;FeSO_4$, $H_2O$, $0.01g\;MnSO_4$, $4H_2O$, $0.2g\;MgSO_4\;7H_2O$, 0.01 g NaCl, $0.05g\;CaCl_2$ per 1 liter deionized water. The pH of media was initially adjusted to 6.0. The inoculation rate was 1.0% (v/v) of the working volume. Temperature was maintained at $28^{\circ}C$. The agitation rate was 100 rpm. The production pattern of dextran was associated with the cell growth. After 24 hr dextran reached its highest concentration of 59.4 g/L. The sucrose was consumed completely after 40 hr. Growth reached stationery phase when sucrose became limiting, regardless of the presence of fructose or mannitol. When the specific growth rate was 0.54 hr-1, utilization averaged 5.8 g/L-hr. The yield and productivity of dextran were 80% and 2.0 g/L-hr, respectively. Dextrans produced by were separated to two different size by an alcohol fraction method. The size of high molecular weight dextran (45% alcohol, v/v), less soluble dextran, was between MW 500,000 and 2,000,000. Soluble dextran (55% alcohol, v/v) was between 70,000 and 150,000. The molecular weight average of total dextran (70% alcohol, v/v) was between 150,000 to 500,000. The enzymatic hydrolyzates of total dextran of ATCC 13146 showed branched dextrans by Penicillium dextranase contained of glucose, isomaltose, isomaltotriose, and isomaltooligosaccharides greater than DP4 (degree of polymerization) that had branch points. Compounds greater than DP4 were branched isomaltooligosaacharides. Hydrolysates by the Lipomyces dextranase produced the same composition of oligosaccharides as those by Penicillin dextranase.

• KSBB Journal
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• 제27권6호
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• pp.352-360
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• 2012

Bacillus clausii I-52 which produced SDS- and $H_2O_2$-tolerant extracellular alkaline protease (BCAP) was isolated from heavily polluted tidal mud flat of West Sea in Incheon, Korea and stable strain (transformant C5) of B. clausii I-52 harboring another copy of BCAP gene in the chromosome was developed using the chromosome integration vector, pHPS9-fuBCAP. When investigated the production of BCAP using B. clausii transformant C5 through pilot-scale submerged fermentation (500 L) at $37^{\circ}C$ for 30 h with an aeration rate of 1 vvm and agitation rate of 250 rpm, protease yield of approximately 105,700 U/mL was achieved using an optimized medium (soybean meal 2%, wheat flour 1%, sodium citrate 0.5%, $K_2HPO_4$ 0.4%, $Na_2HPO_4$ 0.1%, NaCl 0.4%, $MgSO_4{\cdot}7H_2O$ 0.01%, $FeSO_4{\cdot}7H_2O$ 0.05%, liquid maltose 2.5%, $Na_2CO_3$ 0.6%). The enzyme stability of BCAP was increased by addition of polyols (10%, v/v) and also, the stabilities of BCAP towards not only the thermal-induced inactivation at $50^{\circ}C$ but also the SDS and $H_2O_2$-induced inactivation at $50^{\circ}C$ were enhanced. Among the polyols examined, the best result was obtained with propylene glycol (10%, v/v). The BCAP supplemented with propylene glycol exhibited extreme stability against not only the detergent components such as ${\alpha}$-orephin sulfonate (AOS) and zeolite but also the commercial detergent preparations. The granulized enzyme of BCAP was prepared with approximately 1,310,000 U/g of granule. Wash performance analysis using EMPA test fabrics revealed that BCAP granule exhibited high efficiency for removal of protein stains in the presence of anionic surfactants as well as bleaching agents. When compared to Savinase 6T$^{(R)}$ and Everlase 6T$^{(R)}$ manufactured by Novozymes, BCAP under this study probably showed similar or higher efficiency for the removal of protein stains. These results suggest that the alkaline protease produced from B. clausii transformant C5 showing high stability against detergents and high wash performance has significant potential and a promising candidate for use as a detergent additive.

• 한국미생물·생명공학회지
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• 제41권1호
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• pp.119-127
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• 2013

선행연구에서 김치발효 후기의 우점종으로 알려진 Lactobacillus sakei의 생육을 저해하는 Leuconostoc 속 23균주와 Weissella 속 45 균주를 김치로부터 분리, 동정하였다. 발효 후기까지 생존할 수 있는 김치발효용 hetero 발효형 종균 선발을 위하여 이들 균주에 대한 내산성을 평가한 결과, Lc. mesenteroides CK0128, W. cibaria CK0633, W. cibaria KK0797 균주가 acetic acid와 lactic acid 혼합용액을 이용하여 pH를 4.3으로 조정한 MRS broth에서 상대적으로 높은 생존율을 보였고, 다량의 세포 외 다당류를 생산하였다. 세균주가 생산하는 항균물질의 분자량은 3,000 Da 이하로 추정되며 Staphylococcus aureus와 Lb. sakei에 대한 생육저해를 나타내었다. 분획한 3,000 Da 이하의 조항균물질 모두가 $121^{\circ}C$, 15분의 열처리에도 항균활성을 유지함으로써 항균물질의 열에 대한 높은 안정성이 확인되었다. pH의 감소에 따른 항균활성의 증가가 pH 5 이하의 산성조건에서 확인되어, 이들 항균물질은 pH 5 이하의 산성조건에서 활성을 갖는 것으로 추정된다. ${\alpha}$-amylase, lipase, pepsin, proteinase K 처리가 항균활성에 아무런 영향을 미치지 않는 것으로 보아 이들 균주가 생산하는 항균물질은 탄수화물, 지질을 포함하지 않으며, 비단백질성 물질로 추정된다. 또한, 선발균주가 생산하는 비단백질성 항균물질은 식중독균의 생육을 효과적으로 저해하였다.

• Journal of Microbiology and Biotechnology
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• 제14권2호
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• pp.276-283
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• 2004

Screening was performed to isolate cellulose-producing microorganisms from the Korean traditional fermented persimmon vinegar. The resulting strain, KJ $145^{T}$, was then taxonomically investigated by phenotypic characterization, particularly chemotaxonomic, and by phylogenetic inference based on a 16S rDNA sequence analysis including other related taxa. Strain KJ $145^{T}$ was found to grow rapidly and form pale white colonies with smooth to rough surfaces on a GYC agar. Strain KJ $145^T$ also produced acetate from ethanol, and was tolerable to 10% ethanol in SM medium. In a static culture, a thick cellulose pellicle was produced, and in GYC broth, the strain grew at temperatures ranging from 28 to $40^\circ{C}$ with an optimum pH of 4.0. The genomic DNA G+C content of strain KJ $145^T$ was 61.9 mol%, and the predominant ubiquinone was Q 10 as the major quinone and Q9 as the minor quinone. The major cellular fatty acids were $C_{16:0}$ and the sum in feature 7 ($C_{18:1}$ w9c, w12t and/or w7c). A 16S rRNA-targeted oligonucleotide probe specific for strain KJ $145^T$was constructed, and the phylogenetic position of the new species was derived from a 16S rDNA-based tree. When comparing the 16S rDNA nucleotide sequences, strain KJ $145^T$ was found to be most closely related to G. hansenii LMG $1527^T$ (99.2%), although KJ $145^T$ was still distinct from G. hansenii LMG $l527^T$ and G. xylinus LMG $1515^T$ in certain phenotypic characteristics. Therefore, on the basis of 16S rDNA sequences and taxonomic characteristics, it is proposed that strain KJ $145^T$ should be placed in the genus Gluconacetobacter as a new species, Gluconacetobacter persimmonis sp. nov., under the type-strain KJ $145^T$ (=KCTC =$10175BP^T$=KCCM=$10354^T$).