• Applied Biological Chemistry
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• 제29권1호
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• pp.3-9
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• 1986

Alkane 효모의 유성(有性) 생활환(生活環)을 이용한 유전적 해석과 대사경로(代謝經路)에 관한 기초자료를 얻고자 토양과 오염된 치이즈에서 citric acid의 생산성이 높은 균주를 분리하여 동정하고 교잡(交雜)에 의하여 2배체(倍體) 체화(體化)하였으며, 이들의 유전적, 생화학적 및 효소학적 특성을 검토하여 다음과 같은 결과를 얻었다. Citric acid와 isocitric acid를 생산하는 CJ2, CJ7과 CJ8 균주는 Saccharomycopsis lipolytica의 교배형(交配型) A, B와 B로 각각 동정되어 교잡(交雜)과 포자형성(胞子形成)에 의하여 얻은 배수체(倍數體)의 감수분열(減數分裂) 분리를 행한바 재조합형(再組合型) 자손이 얻어졌다. 모든 균주는 glucose배지보다 n-hexadecane배지에서 재친(再親) 1배체(倍體)보다 2배체(倍體)가 citric acid를 많이 생산하였고 isocitrate Iyase의 비활성(比活性)은 n-hexadecane배지에서 생육한 세포가 glucose배지에서 생육한 세포보다 $15{\sim}20$배 높았지만 citrate synthetase의 비활성(比活性)은 탄소원에 의하여는 거의 영향을 받지 않았다. 또한 이들 효소의 비활성(比活性)과 citric acid의 생산 사이에는 균주와 배수성에 관계없이 상관관계가 적었다.

• 미생물학회지
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• 제26권4호
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• pp.339-347
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• 1988

The rate of bacterial degradation of hydrocarbon was estimated for the measurment of the self-purification capacity of the aquatic ecosystem. Strain ND601P-2, selected as petroleum degrading bacteria from Nakdong River Estuary with high degradability of petroleum, transformed 42% of hexadecane to $CO_{2}$ or cell mateials under the conditions of $25^{\circ}C$, 0.03M NaCl, 167mg-$NH_{4}^+/1, 950 mg-PO_{4}^{3-}$/1, 50 mg-hexadecane/1. The mineralization rate was found to be significantly affected by the temperature and the $Q_{10}$ value was 2.2. Teh optimal salinity of the strain ND601P-2 was 2o/oo. The increased salinity caused the elevation of % respiration value and the prolonged lag phase.

• Toxicological Research
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• 제7권2호
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• pp.129-139
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• 1991

Preventive effect of red ginseng saponin on experimentally-induced hyperkeratosis was investigated by ultrastructural observation, skin weight and epidermal lipid analysis. Hexadecane increased skin weight per unit area and epidermal lipids, free fatty acids, cholesterol and triglyceride in guinea pig skin. Topical application of ginseng saponin reduced these hyperkeratotic responses regradless of the concentration and the purity of ginseng saponin. Ultrastructurally, lipids and empty space-containing multiple horny cells were piled and nuclear remnants, desmosome, desmosomal bodies, tight junction were shown in the stratum corneum of hexadecane-treated skin.

• 한국미생물·생명공학회지
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• 제6권4호
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• pp.173-179
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• 1978

1) 고온성으로 탄화수소를 자화할 수 있는 균체를 생산하는 목적으로 90여점의 시료로부터 세 균주의 효모를 선별하여 다음의 결과를 얻었다. 2) 선정된 세 균주 효모의 최적생육온도는 4$0^{\circ}C$~45$^{\circ}C$였과. 그리고 이들은 각각 Candida tropicalis (strain A-28), Torulopsis molisichiana (strain B-8) 그리고 Candide krusei (strain C-15)로 각각 동정되었다. 3) 특히 균주 A-28은 tetradecane, hexadecane 과 octadecane을 다같이 쉽게 자화하였고 B-8과 C-15 균주는 다른 n-paraffin 보다 hexadecane을 잘 자화하였다. 4) 선정된 세 균주효모의 세대시간은 3.4.~4.0 시간, 비증식속도는 0.170~0.215이고 그리고 균체수율은 86~98%이였다. 5) 이들 균체의 조단백질은 48.2~61.5%, 지방은 3.7~8.0%, 조섬유는 3.5~4.2%, 회분은 5.6~6.7%, 무질소가용성 물질은 23.5~31.8%였고, thiamine은 0.28~0.93 mg%, riboflavin 6.03~7.3 mg%이었다. 6) 균체단백질의 아미노산조성은 비교적 골고루 함유되었다. 그러나 함황(sulfur containing) amino acid는 극히 적었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권3호
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• pp.245-250
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• 2006

The effects of aliphatic hydrocarbons (n-hexadecane and n-dodecane) on the volumetric oxygen mass transfer coefficient $(k_L\;a)$ were studied in flat alveolar airlift reactor and continuous stirred tank reactors (CSTRs). In the flat alveolar airlift reactor, high aeration rates (>2vvm) were required in order to obtain efficient organic-aqueous phase dispersion and reliable $k_La$ measurements. Addition of 1% (v/v) n-hexadecane or n-dodecane increased the $k_La$ 1.55- and 1.33-fold, respectively, compared to the control (superficial velocity: $25.8{\times}10^{-3}m/s$, sparger orifice diameter: 0.5 mm). Analysis of the gas-liquid interfacial area a and the liquid film mass transfer coefficient $k_L$ suggests that the observed $k_La$ increase was a function of the media's liquid film mass transfer. Addition of 1% (v/v) n-hexadecane or n-dodecane to analogous setups using CSTRs led to a $k_La$ increase by a factor of 1.68 and 1.36, respectively (superficial velocity: $2.1{\times}10^{-3}m/s$, stirring rate: 250 rpm). These results propose that low-concentration addition of oxygen-vectors to aerobic microbial cultures has additional benefit relative to incubation in purely aqueous media.

• KSBB Journal
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• 제11권5호
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• pp.586-592
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• 1996

본 연구에서는 단일 탄소원인 포도당으로부터 P PHA를 생산하는 콩시균 Pseudomonas sp. HJ를 보다 정확하게 동정하기 위하여 수치분류를 실시하 였으며, 또한 보조기질을 첨가하였을때의 PHB/HV 합성 양상을 검토하였다. Pseudomonas sp. HJ는 각 대조균주들중에서 Pseudomonas picketti와 가장 유 사도가 높은 것으로 나타났다(78.8%). 그러나 수치 분류에 서 통일 균종에 포함될 수 있는 유샤도는 85 % 정도인 것으로 얄려져 있으므로, 본 공시균 P Pseudomonas sp. HJ는 Pseudomonas 속의 다른 종 (species)이거나 새로운 종(species)일 가능성이 높 았다. 보조기 질로 hexadecane과 propionic acid를 각각 0.4%씩 첨가했을 경우, 농도증가에 비례하여 H HV 함량은 점차 증가하여 각각 60.8 mol%, 44.9 mol%까지 축적되었다. PHB/HV내의 HV 함량은 p propionic acid냐 hexadecane의 농도를 달리하여 첨가함으로써 조절할 수 있었다. 보조기질로 propl- onic acid 0.2 %를 대수기 중기 인 배양 18시간에 첨 가하였을때 균체 생육이 가장 우수하였으나, HV monomer의 비율은 대수기 말기인 배양 24시간대에 첨가하였을때 49.6 mol%로 가장 높았다.

• KSBB Journal
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• 제17권3호
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• pp.302-306
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• 2002

탈황공정에 많이 이용되는 미생물인 Rhodococcus sp. Strain IGTS8이 hexadecane과 배지 수용액 혼합물에서 생성하는 biosurfactant의 성분분석과 계면물성을 연구하였다. TLC를 이용한 정성적 성분분석 결과 생성되는 biosurfactant는 glucose mycolate와 trehalose monomycolate임을 확인하였고 임계 미셀농도는 pH 6∼6.5와 pH 10∼10.5에서 100 mL의 수용액에 biosurfactant가 0.1∼0.15 g 첨가될 때였으며 유화파괴 속도는 pH가 높을수록 증가하였다.

• Journal of Microbiology and Biotechnology
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• 제19권7호
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• pp.651-657
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• 2009

Shifts in the activity and diversity of microbes involved in aliphatic and aromatic hydrocarbon degradation in contaminated soil were investigated. Subsurface soil was collected from a gas station that had been abandoned since 1995 owing to ground subsidence. The total petroleum hydrocarbon content of the sample was approximately 2,100 mg/kg, and that of the soil below a gas pump was over 23,000 mg/kg. Enrichment cultures were grown in mineral medium that contained hexadecane (H) or naphthalene (N) at a concentration of 200 mg/l. In the Henrichment culture, a real-time PCR assay revealed that the 16S rRNA gene copy number increased from $1.2{\times}10^5$to $8.6{\times}10^6$with no lag phase, representing an approximately 70-fold increase. In the N-enrichment culture, the 16S rRNA copy number increased about 13-fold after 48 h, from $6.3{\times}10^4$to $8.3{\times}10^5$. Microbial communities in the enrichment cultures were studied by denaturing gradient gel electrophoresis and by analysis of 16S rRNA gene libraries. Before the addition of hydrocarbons, the gas station soil contained primarily Alpha- and Gammaproteobacteria. During growth in the H-enrichment culture, the contribution of Bacteriodetes to the microbial community increased significantly. On the other hand, during N-enrichment, the Betaproteobacteria population increased conspicuously. These results suggest that specific phylotypes of bacteria were associated with the degradation of each hydrocarbon.

• 한국수소및신에너지학회논문집
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• 제15권2호
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• pp.119-128
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• 2004

DME(Dimethyl Ether) was directly produced from the synthesis gas using the slurry phase reactor. The catalyst for DME production prepared two types (A type; Cu:Zn:Al=57:33:10, B type; Cu:Zn:Al=40:45:15, molar ratio). It was evaluated for the effect of the reaction medium oil using the small size slurry phase reactor. DME production yield and the methanol selectivity decreased in the order: n-hexadecane oil> mineral oil> therminol oil. The long-term test of DME production was carried out using A and B type catalyst, and n-hexadecane oil and mineral oil, respectively. It was confirmed that the use of A type for the catalyst and n-hexadecane for the reaction medium oil was very useful for the viewpoint of the DME production form the synthesis gas.

• 한국환경과학회지
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• 제11권3호
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• pp.177-182
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• 2002

A biosurfactant-producing microorganism was isolated from activated sludge by enrichment culture when grown on a minimal salt medium containing n-hexadecane as a sole carbon source. This microorganism was identified as Pseudomonas sp. and it was named Pseudomonas sp. EL-G527. It's optimal culture condition is 2% n-hexadecane, 0.2% NH$_4$NO$_3$, 0.3% KH$_2$PO$_4$, 0.3% $K_2$HPO$_4$, 0.02% MgSO$_4$ㆍ7$H_2O$, 0.0025% CaCk$_2$ㆍ6$H_2O$, 0.0015% FeSO$_4$ㆍ7$H_2O$ in 1$\ell$ distilled water and initial pH 7.0. Cultivation was initiated with a 2% inoculum obtained from starter cultures grown in 30 $m\ell$ of the same medium in 250 $m\ell$ flask. They were cultivated at 3$0^{\circ}C$ in reciprocal shaking incubator and the highest biosurfactant production was observed after 4 days.