• Journal of Microbiology and Biotechnology
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• v.20 no.5
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• pp.853-861
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• 2010

High substrate costs decrease the profitability of polyhydroxyalkanoates (PHAs) production, and thus low-cost carbon substrates coming from agricultural and industrial residuals are tested for the production of these biopolymers. Among them, crude glycerol, formed as a by-product during biodiesel production, seems to be the most promising source of carbon. The object of this study was to characterize the mixed population responsible for the conversion of crude glycerol into PHAs by cultivation-dependent and -independent methods. Enrichment of the microbial community was monitored by applying the Ribosomal Intergenic Spacer Analysis (RISA), and the identification of community members was based on 16S rRNA gene sequencing of cultivable species. Molecular analysis revealed that mixed populations consisted of microorganisms affiliated with four bacterial lineages: ${\alpha}$, ${\gamma}$-Proteobacteria, Actinobacteria, and Bacteroides. Among these, three Pseudomonas strains and Rhodobacter sp. possessed genes coding for polyhydroxyalkanoates synthase. Comparative analysis revealed that most of the microorganisms detected by direct molecular analysis were obtained by the traditional culturing method.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.3
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• pp.365-370
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• 2014

Objectives: The major objective is development of an eco-friendly non-phthalate plasticizer using crude glycol derived from the biodiesel process. Methods: Glycerol monolaurate(GML) was synthesized from glycol and triglyrcerides. Glycerol diacetomonolaurate(GDAL) was synthesized from GML and acetic acid. Results: The synthesis of the GDAL plasticizer was measured with nuclear magnetic resonance spectroscopy(NMR). Mechanical properties were measured by universal testing machine(UTM) and the experimental values were compared with phthalate plasticizers such as dioctyl phthalate(DOP). In particular, the values for tensile strength and elongations with GDAL were higher than with DOP. Conclusions: We confirmed the development of an eco-friendly non-phthalate plasticizer by NMR. Based on our results, applicability for food and drug packaging materials was found.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.309-319
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• 1996

Properties as related to the utilization of the crude proteases extracted from the muscle and viscera of fish (2 dark fleshed lish; anchovy, Engraulis japonica, and gizzard-shad, Clupanoda punctatus; 2 white fleshed fish; seabass, Lateolabrax japonicus, and sole, Pleuronichthys cornutus) were studied. Proteolytic activity of the muscle protease was slightly inhibited with the increase of sodium chloride concentration and it was apparent against the yellowtail myofibrillar protein than casein substrate. Proteolytic activities of the seabass and sole visceral crude protease were inhibited to 50 to $60\%\;by\;25\%$ of sodium chloride, but those of anchovy and gizzard-shad viscera crude enzymes were not influenced by sodium chloride. The vacuum freeze-dried crude protease and glycerol-mixed crude pretense of gizzard-shad and seabass muscles were almost lost their activities on the 16th week of storage, while those from the viscera of the fish were relatively stable. Degradation of the yellowtail myofibrillar protein by the anchovy muscle and viscera crude pretenses rapidly proceeded in the beginning of the reaction and the degraded products were mainly distributed in the range of 6 to 15 kDa electrophoretically.

• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.497-503
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• 2016

This study aimed to optimize the culture conditions of recombinant Escherichia coli expressing otsBA using crude glycerol for the enhanced production of trehalose. The effects of culture temperature and isopropyl ${\beta}$-D-1-thiogalactopyranoside (IPTG)-induction were investigated. Trehalose production and cell growth were highest when cells were cultured at $37^{\circ}C$ and induced with IPTG. The concentrations of IPTG, validamycin A, and NaCl were optimized using Box-Behnken design. Statistical analyses of the experimental data revealed that the concentrations of IPTG and NaCl had significant effects on trehalose production, but that of validamycin A did not. Contour plot analysis and model calculation showed that the highest amount of trehalose could be produced at 298 mM NaCl and 0.1 mM IPTG. Under these optimal conditions, the optical density at 600 nm and trehalose production were $5.4{\pm}0.2$ and $304{\pm}15mg/l$, respectively.

• Korean Journal of Agricultural Science
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• v.40 no.1
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• pp.35-45
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• 2013

The fat content, fatty acid composition, trans fatty acid content and triacylglycerol (TAG) composition of 22 chocolates (domestics 8, foreigns 14) collected from the Korea distribution markets were investigated. The crude fat was extracted by acid hydrolysis method and analyzed by gas chromatography (GC) and reversed-phase HPLC for fatty acid and TAG compositions, respectively. The crude fat content of all chocolates varied between 30.11% and 49.59%. The major fatty acids in most of the chocolates were palmitic acid (19.36~31.15 wt%), stearic acid (5.11~36.32 wt%) and oleic acid (18.77~36.68 wt%). Whereas lauric acid (approximately 35.43 wt%) was detected in chocolate fat of sample No. 18. High oleic acid content was observed for the sn-2 position fatty acid with a range from 64.91% to 86.93%. Trans fatty acid contents in domestic chocolates (sample No. 1~8) and foreign chocolates (sample No. 9~22) were 0.03~0.59 wt% (0.01~0.19 g/100g chocolate) and 0.05~6.32 wt% (0.02~1.99 g/100g chocolate), respectively. In TAG composition, TAGs such as POP/PPO(1,3(2)-palmitoyl-2(3)-oleoyl glycerol, PN=48), POS/PSO(palmitoyl-oleoyl-stearoyl glycerol or palmitoyl-stearoyl-oleoyl glycerol, PN=50), SOS/SSO(1,3(2)-stearoyl-2(3)-oleoyl glycerol, PN=50) were mainly detected in most of the chocolates. The peaks of TAG with low PN (ex, 32-34, 36-38, and 40-42) were detected in No. 18 chocolate fat because of containing short chain fatty acid such as lauric acid.

• Journal of Microbiology and Biotechnology
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• v.18 no.12
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• pp.1908-1914
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• 2008

An alkaliphilic bacterium, Bacillus clausii SKAL-16, was isolated from soil that had been contaminated with vegetable oil. The optimal pH and general pH range for bacterial growth was 8, and 7 to 10, respectively. The bacterium could grow on tributyrin and glycerol, but could not grow on acetate and butyrate. The SKAL-16 strain excreted butyric acid during growth on tributyrin, and selectively ingested glycerol during growth on a mixture of butyric acid and glycerol. The SKAL-16 generated intracellular lipase, but did not produce esterase and extracellular lipase. The DNA fragment amplified with the chromosomal DNA of SKAL-16 and primers designed on the basis of the esterase-coding gene of Bacillus clausii KSM-KI6 was not identical with the esterase-coding gene contained in the GenBank database. Pyruvate dehydrogenase, isocitrate dehydrogenase, and malate dehydrogenase activities were detected in the cell-free extract (crude enzyme).

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.1
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• pp.110-118
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• 2010

Supercritical treatment of liquefaction technology for rice hull was investigated the biomass conversion rate and evaluated its crude oil in respect to feasibility of burner in order to heat the green house. The reaction was carried out in a 5,000 mL liquefaction system with dispenser and external electrical furnace. Raw materials (160 g) of rice hull and 3,000 mL of different solvents were fed into the reactor. It was observed that the maximum crude oil yield was about 84.4 % with 1-butanol. The calorific value of crude oil from ethanol solvent were 7,752 kcal/kg. Furthermore, in case study of co-solvent with ethanol and bulk-glycerol, it observed that more than 80 % of rice hull was decomposed and liquefied in its solvent at $315{\sim}326^{\circ}C$ for 30 min. For the development of applicable bio-fuel from rice hull, it was considered that its feasibility is necessary to be carried out for co-solvent soluble portions. Regarding to utilize the crude oil into burner as fuel, it was observed that its calorific value was lower at approximately 24 % than the diesel. Also, flame length from crude oil at lower temperature was decreasing due to incomplete incineration. The temperature of warm wind on the burner was maintained between 63 and $65^{\circ}C$, and the temperature of emission line was appeared at $350{\sim}380^{\circ}C$.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.3
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• pp.322-327
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• 2015

Objectives: The major objective of this study is the oral dose toxicity test and skin irritation test of eco-friendly plasticizer using crude glycerol derived from the biodiesel process. Methods: Glyceroldiacetate laurate(GDL) was synthesized from glycerol monolaurat(GML) and acetic acid. The synthesis of the GDL plasticizer was measured with nuclear magnetic resonance spectroscop(NMR) and FT-IR(Fourier Transform Infrared Spectrometer). To provide information on the safety of GDL, we carried out an oral dose toxicity test for GDL in Sprague-Dawley rats. Also, we carried out a skin irritation test for GDL in New Zealand White rabbits. Results: The oral dose toxicity test in Sprague-Dawley rats showed that GDL is a non-toxic material. The result of the skin irritation test on New Zealand White rabbits showed that GDL is non-irritating. Conclusions: From the results of oral dose toxicity test and skin irritation test, we concluded that the developed plasticizer showed excellent eco-friendly property. Based on our results, we confirmed the development of an eco-friendly non-phthalate plasticizer. Applicability for PVC toys and food and drug packaging materials was found.

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.759-765
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• 2012

As the biodiesel production is increasing rapidly, the crude glycerol, which is principal by-product of biodiesel production, has also been generated in a large amount. Many research studies on value-added utilization of glycerol are under investigation. 1,3-Propandiol is a promising chemical which can be produced from fermentation of glycerol because the application of 1,3-propanediol is mainly in the production of bio-PTT (Poly(trimethylene terephthalate). However, the cost of downstream processes in the biological production of 1,3-propanediol can make a high portion in the total production cost. This review summarizes the present state of separation processes in each step studied for the removal of impurities and the recovery of 1,3-propanediol from its fermentation broth. Furthermore, ATPE (Aqueous Two Phases Extraction) process is suggested as an attractive alternative for the primary separation process of 1,3-propanediol because ATPE is convenient for the simultaneous removal of microbial cells and impurities such as salts of organic acids and the separation of 1,3-propanediol from fermentation broth.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.12
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• pp.1882-1888
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• 2019

Objective: An experiment was conducted to evaluate the effects of increasing levels of crude glycerin (0%, 6%, 12%, and 18%) used as a substitute for corn in lamb feed on the quantitative characteristics of the carcass. Methods: A total of 40 crossbred Santa $In{\hat{e}}s$ lambs that were four months old with a mean initial weight of $21.0{\pm}0.8kg$ were randomly distributed in four treatments with ten replicates. The animals were slaughtered after 66 days of confinement. The effects of crude glycerin as a replacement for corn in the diet of the lambs on the carcass characteristics, commercial cut weight and yield and carcass measurements were studied. Results: There was an increasing linear effect for body weight at slaughter with the replacement of corn by crude glycerin. The dry matter and metabolizable energy intakes, weight of the empty body, hot carcass weight and cold carcass weight showed a quadratic effect, with maximum crude glycerin levels estimated at 10.9%, 9.8%, 10.83%, 11.78%, and 11.35%, respectively. The initial pH was not influenced by the replacement of corn for crude glycerin, while the final pH presented a quadratic effect. The other parameters of the carcass and the weights and yields of commercial cuts were not influenced. There was also no effect of the diets on carcass morphometric measurements, except for the thoracic perimeter and the carcass compactness index, which presented quadratic and linear effects, respectively. Conclusion: Crude glycerin can replace up to 18% of corn because it favours muscle tissue deposition without promoting changes in the main carcass characteristics of lambs.