• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.313-320
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• 1984

In order to elucidate the oxidative stabilities of mackerel lipids, lipids were extracted from ordinary muscle, dark muscle, skin (including subcutaneous adipose tissue) and viscera, and then stored at $30^{\circ}C$. The changes of lipids were examined periodically by measuring peroxide value (POV), thiobarbituric acid (TBA), weighing method, acid value (AV) and iodine value (IV), Fatty acid composition of lipids was analyzed by GLC. The results obtained are summerized as follows: The velocity of lipid oxidation during the storage was differ from the extracting part of the sample. It was laster in skin, viscera, dark muscle and ordinary muscle in the order. Ratio of polar lipid fractions in total lipids was ranged from 5 to $15\%$, and the highest result was observed in dark muscle. Main fatty acids of the lipids were $C_{16:0}$ acid ($22.0{\sim}25.9\%$), $C_{18:1}$ acid ($22.3{\sim}26.7\%$) and $C_{22:6}$ acid ($9.6{\sim}13.4\%$), and $C_{22:6}$ acid content ($\%$) was the highest in lipid from dark muscle, and the lowest in lipid from skin. Monoenoic acid content ($\%$) was higher in the non-polar lipid than in the polar lipid, on the contrary. polyenoic acid content ($\%$) was higher in the polar lipid than in the non-polar lipid. Polyunsaturated fatty acids of the lipids, $C_{20:5}$ acid and $C_{22:6}$ acid, decreased predominantly with oxidation during storage, while saturated acids, $C_{14:0}$ acid and $C_{16:0}$ acid, increased predominantly. The polar lipid fractions were oxidized much faster than the non-polar lipid fractions.

• Journal of Nutrition and Health
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• v.13 no.1
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• pp.65-69
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• 1980

When the Hair-tail was dried in the direct sunlight, the changes of acid value, TBA value, peroxide value and fatty acid composition of its muscle were observed. The results of the observation were as follows: 1) Total content of the lipid in the fresh Hair-tai1 was 9.91%, that of saturated fatty acid was 43.3%, and that of unsaturated fatty acid was 56.7%. The TBA value, the peroxide value and acid value were slowly increased until the 4th week, then were somewhat quickly increased in the 5th week. 2) The analysis of the fatty acid composition of the fresh Hair-tail lipid by meas of G.L.C method showed the order of the content quantities such as $C_{18}\;:\;1(44.3%),$ $C_{16}(29.22%),$ $C_{16}\;:\;1(11.3%),$ $C_{14}(6.6%),$ $C_{18}(5.4%),$ $C_{17}(2%),$ $C_{17}\;:\;1(1.1%),$ $C_{18}(2%),$ were found to be a trace. 3) The content of the unsaturated fatty acid was shown to be decreased while the level of the saturated fatty acid was increased during the sun drying.

• Current Research on Agriculture and Life Sciences
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• v.10
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• pp.125-135
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• 1992

Nine strains of xyl mutants that could not utilize xylose as a carbon source were isolated from E. coli JM109 by the treatment of NTG in order to investigate the regulation of xylose operon and to use recipient cells for the cloning of xylR gene. For the characterization of all isolated mutants, colony colors of all mutants on MacConkey-xylose and MacConkey-xylulose agar plate were observed for the utilization of xylose and xylulose, and the growth level and the activity of xylose isomerase and xylulokinase were determined in need. The isolated xylR/T mutants formed the white colony on MacConkey-xy-lose and MacConkey-xylulose agar plate. They did not detect the activity of xylose isomerase, and the activity of xylose isomerase was not restored in transformants of xylR/T mutant with pEX13 which contained xylA gene. xylR and xylT mutants were classified from xylR/T mutants depending upon the growth level in minimal medium. xylT mutants; DH13, DH121 and DH125 could grow a little in that medium, but xylR mutants; DH10, DH53, and DH60 could not grow that medium.

• Journal of Plant Biotechnology
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• v.45 no.2
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• pp.90-101
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• 2018

Strawberry (Fragaria ${\times}$ ananassa) is a globally-cultivated and popular fruit crop, prized for its flavor and nutritional value. Sweetness, a key determinant of fruit quality, depends on the sugar composition and concentration. We selected eight strawberry cultivars based on the fruit soluble solids content to represent high and low sugar content groups. The average soluble solid content was $13.6^{\circ}Brix$ (Okmae, Geumsil, Aram, and Maehyang) and $2.9^{\circ}Brix$ (Missionary, Camino Real, Portola, and Gilgyung53), for the high and low sugar content groups, respectively. Sucrose was the main sugar in the cultivars with high sugar content, whereas fructose was the main component in the low sugar content cultivars. Fruit starch concentration ranged from $3.247{\pm}0.056$ to $3.850{\pm}0.055g/100g$, with a 12% higher concentration in the high sugar content cultivars. Additionally, we identified 41 sugar metabolism-related genes in Fragaria ${\times}$ ananassa and analyzed the relationship between their transcripts and the sugar accumulation in fruit. FaGPT1, FaTMT1, FaHXK1, FaPHS1, FaINVA-3, and FacxINV2-1 were highly expressed in the high sugar content cultivars, while FapGlcT, FaTMT2-1, FaPHS2-1, FaSUSY1-1, and FaSUSY1-2 were highly expressed in the low sugar content cultivars. In general, a greater number of genes encoding sugar transporters or involved in sugar synthesis were highly expressed in the high sugar content cultivars. Contrarily, genes involved in sugar degradation were preferentially transcribed in the low sugar content cultivars. Although gene expression was not perfectly proportional to sugar content or concentration, our analysis of the genes involved in sugar metabolism and accumulation in strawberries provides a framework for further studies and for the subsequent engineering of sugar metabolism to enhance fruit quality.

• Journal of Chest Surgery
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• v.46 no.1
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• pp.1-13
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• 2013

Background: Glutaraldehyde (GA) is a widely used cross-linking agent for improving mechanical properties and resistance to enzymatic degradation of collagenous tissue, but it has several drawbacks such as calcification and cytotoxicity. The aim of this study was to find the alternative effective cross-linking methods to GA. Materials and Methods: Bovine pericardium was processed with GA with ethanol+octanol and glycine detoxification, and polyethylene glycol (PG) space filler, dimethyl 3,3'-dithiobispropionimidate (DTBP), 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) treatment, and the physical fixation of ultraviolet irradiation were done. The biologic material properties of variously treated pericardial tissues were assessed by biochemical, mechanical and histological tests. Treated pericardial tissues were also implanted subcutaneously or intramuscularly into the rabbit for 10 weeks to assess the xenoreactive antibody response of immunoglobulin G and M, their anti-calcification effect. Results: The biochemical and mechanical properties of EDC fixed pericardial tissues were comparable to the GA fixed tissue. The cytotoxicity was lowest in space filler treated GA fixed group. In rabbit subcutaneous or intramuscular implantation models, decellularization, space filler, EDC treatment group showed significantly lower calcium content than GA only and DTBP treatment group (p<0.05, analysis of variance). The titer of anti $Gal{\alpha}1-3Gal{\beta}1$-4GlcNAc-R antibodies did not change in the postimplantation serial enzyme-linked immunosorbent assay. Hematoxylin and eosin and von Kossa staining showed that decellularization, space filler, EDC, and ultraviolet treatment had less inflammatory cell infiltration and calcium deposits. Conclusion: The decellularization process, PG filler, and EDC treatments are good alternative cross-linking methods compared to GA only fixation and primary amine of DTBP treatment for cardiovascular xenograft preservation in terms of the collagen cross-linking stability and in vivo anti-calcification effects.

• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.960-968
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• 2003

A bacterial isolate showing a strong endochitosanase activity was isolated from soil and then characterized. The isolate was identified and designated as Bacillus cereus P16, based on morphological and biochemical properties, assimilation tests, cellular fatty acids pattern, along with 16S rRNA gene sequence. The optimized medium for producing extracellular chitosanase in a batch culture contained 1% tryptone, 0.5% chitosan, and 1% NaCl (pH 7.0). Powder chitosan and tryptone served the best as carbon and nitrogen sources, respectively, for the chitosanase production. Chitosanase activity was the highest when culture was completed at $37^{\circ}C$ among various temperatures ($20-42^{\circ}C$) tested in a shaking incubator (200 rpm). The levels of chitosanase activity in the culture fluid were 2.0 U/ml and 3.8 U/ml, respectively, when incubated in a flask for 60 h and in a jar fermenter for 24 h. The culture supernatant showed a strong liquefying activity on the soluble chitosan. The viscosity of 1% chitosan solution, that was incubated with the culture supernatant, was rapidly decreased, suggesting the secretion of endochitosanolytic enzymes by P16. The culture fluid revealed six endo-type chitosanase isozymes, two major (38 and 45 kD), and four minor (54, 65, 82, and 96 kD) forms by staining profile. The crude enzymes were very stable, and full activity was maintained for 4 weeks at $4^{\circ}C\;or\;-20^{\circ}C$ in the culture supernatant, suggesting a highly desirable stability rate for making an industrial application of the crude enzymes. The supernatant also cleaved the insoluble chitosan powder, but the hydrolysis rate was much lower. The enzymic degradation products of chitosan contained $(GlcN)_n$ (n=2-8). The concentration of chitosan in the reaction mixture of the crude enzyme affected the chitooligosaccharides composition of the hydrolysis products. When the higher concentration of chitosan was used, the higher degree of polymerized chitooligosaccharides were produced. By comparison with other commercial chitosanase preparations, P16 was indeed found to be a valuable enzyme source for industrial production of chitooligosaccharides from chitosan.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.205-210
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• 1998

This study was carried out for the dietary safety based on the level of pesticide residues in 19 kinds of agricultural products consumed in Kangwon-do, Korea. From April 1995 to December 1997, eight organochlorine pesticides in 673 samples were analyzed by using GLC-ECD. According to the results, one kind of pesticides were detected in 159(23.6%) samples and two kinds were in 24(15.1%). While Chlorobenzilate, Dicofol and Tetradifon were not found. Detection ranges of pesticides were $0.001{\sim}0.117ppm$ for DDT, $0.001{\sim}0.095ppm$ for ${\gamma}-BHC$, $0.001{\sim}0.067ppm$ for ${\alpha},{\beta}-Endosulfan$, $0.003{\sim}0.250ppm$ for Chlorothalonil and 0.033ppm for Captafol. Average residues were 0.006ppm for DDT, 0.009ppm for ${\gamma}-BHC$, 0.008ppm for ${\alpha},{\beta}-Endosulfan$, 0.024ppm for Chlorothalonil and 0.033ppm for Captafol, respectively. Consequently, all of the organochlorine pesticide residues in the analyzed samples were within the maximum residue limits.

• The Korean Journal of Pesticide Science
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• v.8 no.2
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• pp.103-106
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• 2004

To confirm physico-chemical stability of formulated products, this study was conducted under different storage conditions; room temperature and accelerated temperature of $54^{\circ}C$. The tested pesticide formulations were dichlorvos 50% EC, acephate 50% WP, hymexazol 4% DP, thiram 80% WP and isoprothiolane 12% GR. The selected formulations were stored for 10 weeks and 5 years under the given temperature in maximum and contents of active ingredients were also analyzed by GLC or HPLC after each time of storage. The degradation rates of 5 active ingredients under the two conditions showed a similar trend except acephate. Acephate was rapidly decomposed at $54^{\circ}C$ but slowly decomposed at room temperature, and the degradation rate under the accelerated condition was 2.4 to 5-fold higher than that under the room temperature. Consequently, the stability test on active ingredients in pesticide formulations was able to recommend to be carried out under the accelerated condition except acephate. And the physical properties of all formulations tested under two storage conditions were good.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.4
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• pp.199-204
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• 1977

The patterns of fatty acid composition of lipid extracted from eight species of edible marine benthic algae; i. e. two species of green, five of brown and one of red algae, were investigated quantitatively by using gas liquid chromatography. The total lipid contents in average of the algae were $1.51\%$ in the green algae, $2.81\%$ in brown algae and $1.02\%$ in red algae respectively. Upon analyzing fatty acid composition, green algae contained the highest proportion of $C_{16:0}$ acid and comparatively higher content of $C_{18:1},\;C_{18:2}\;and\;C_{18:3}$ acids than the other algae. In brown angae, $C_{16:0}$ acid content was highest, but not more than that of green algae, and $C_{14:0},\;C_{18:1}$ acids were higher than other $C_{16:1},\;C_{18:2}\;and\;C_{18:3}$ acids while the content of $C_{18:0}$ acid was very low. Red algae showed low content of $C_{14:0},\;C_{18:1},\;C_{18:2}\;and\;C_{18:3}$ acids, but the content of $C_{16:0}$ acid was high as a major component. In regard to the composing patterns of carbon number of fatty acid of algae; i. e. $C_{14},\;C_{15},\;C_{16},\;C_{18}\;and\;C_{22}$ and $C_{22}$ acids, the green algae contained $C_{16}$ and $C_{18}$ acids, the brown algae $C_{16},\;C_{18},\;and\;C_{22}$ and $C_{22}$ acids, and the red algae $C_{15},\;C_{16}$, and $C_{18}$ acids as the major component.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.6
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• pp.506-510
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• 1984

The muscle lipids of cultured and wild eel, Anguilla japonica, were analysed by gas chromatography for fatty acid compositions of total lipid(TL), neutral lipid(NL), phospholipid(PL) and glycolipid(GL). And high performance liquid chromatography(HPLC) patterns of NL were analysed by HPLC. The lipid contents of dorsal muscle of cultured fish are slightly lower than that of wild fish. The contents of TL, NL and PL of wild fish were similar to those of cultured fish, while GL content of wild fish was higher than that of cultured one. In the fatty acid compositions of TL, NL and PL, percentages of $C_{16:0},\;C_{18:1}\;and\;C_{22:6}$ in cultured fish are higher than these in wild one, while percentage of $C_{16:1}$ is lower. Elution patterns in HPLC of NL of wild and cultured eel were slightly different.