• Food Science and Preservation
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• 제8권4호
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• pp.379-384
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• 2001

This study was conducted to investigate the changes in quality of soybean sprouts grown by ozone treatment during storage. Soybean spouts were cultivated under conditions of ozone water watering after soaking in water (W/W), watering after soaking in ozone water (O/W), ozone water watering after soaking in water (W/O) and ozone water watering after soaking in ozone water (O/O). The ozone concentration in soaking of soybean and watering of soybean sprouts was 0.3 ppm, respectively. No significant difference in shelf-life between W/W soybean sprouts and ozone treated samples showed. But shelf-life of soybean sprouts stored in 0.01 ㎜ polyethylene film at 10$\^{C}$ and 20$\^{C}$ prolonged 4 and 2 days, respectively. The slow growth of total microbe in the ozone treated samples stored at 10$\^{C}$ was observed, whereas that of products at 20$\^{C}$ showed rapid growth during storage. However, no great difference occurred among samples in the changes of moisture, vitamin C and chlorophyll content during storage. Higher hardness of soybean spouts stored at 10$\^{C}$ and 20$\^{C}$ was kept in the O/W and W/O products. Color, flavor and overall acceptability evaluated by sensory teat during storage had higher scores in O/W products as compared to the other samples.

• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.306-314
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• 2003

Bio-hydrogenation of $C_{18}$-unsaturated fatty acids released from the hydrolysis of dietary lipids in the rumen, in general, occurs rapidly but the range of hydrogenation is quite large, depending on the degree of unsaturation of fatty acids, the configuration of unsaturated fatty acids, microbial type and the experimental condition. Conjugated linoleic acid (CLA) is incompletely hydrogenated products by rumen microorganisms in ruminant animals. It has been shown to have numerous potential benefits for human health and the richest dietary sources of CLA are bovine milk and milk products. The cis-9, trans-11 is the predominant CLA isomer in bovine products and other isomers can be formed with double bonds in positions 8/10, 10/12, or 11/13. The term CLA refers to this whole group of 18 carbon conjugated fatty acids. Alpha-linolenic acid goes through a similar bio-hydrogenation process producing trans-11 $C_{18:1}$ and $C_{18:0}$, but may not appear to produce CLA as an intermediate. Although the CLA has been mostly derived from the dietary $C_{18:2}$ alternative pathway may be existed due to the extreme microbial diversity in the reticulo-rumen. Regardless of the origin of CLA, manipulation of the bio-hydrogenation process remains the key to increasing CLA in milk and beef by dietary means, by increasing rumen production of CLA. Although the effect of oil supplementation on changes in fatty acid composition in milk seems to be clear its effect on beef is still controversial. Thus further studies are required to enrich the CLA in beef under various dietary and feeding conditions.

• Journal of the Korean Applied Science and Technology
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• 제32권2호
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• pp.281-289
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• 2015

This study investigated the conversion of oil products from polypropylene by using dispersed Co and Mo catalyst on reaction time and concentration change for knowledging liquefation characteristics at low-temperature (425, 450 and $475^{\circ}C$) pyrolysis in a batch reactor. The reaction time was set in 20~80 minutes and the oil products formed during pyrolysis were classfied into gas, gasoline, kero, diesel and heavy oil according to the domestic specification of petroleum products. The pyrolysis conversion rate was showed as Mo catalyst > Co catalyst > Thermal in all reaction time at reaction temperature $450^{\circ}C$. The conversion rate and yields of the pyrolysis products were the most height when Co and Mo Catalyst ratio was 50:50.

• Microbiology and Biotechnology Letters
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• 제14권5호
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• pp.391-397
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• 1986

Three kinds of microoganisms were isolated and identified from the ginseng and ginseng products to research the properties of the molds which spoil the ginseng and ginseng products. The results obtained were as follows: (1) The predominant strains on ginseng products were Aspergillus sp., Penicillium sp.-A and Penicillium sp.-B. These predominant fungi deteriorated ginseng products exclusively, (2) Aspergillus sp. showed the greatest mycelial growth at $40^{\circ}C$ and its optimum pH was 5, meanwhile Pencillium sp. showed the greatest mycelial growth at $30^{\circ}C$ and its optimum pH was 3. (3) The growth of the isolated strains was stimulated with the increase in the concentration of saponin at the lower concentration, meanwhile it was inhibited at 1.0% concentration of saponin.

• Asian-Australasian Journal of Animal Sciences
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• 제30권3호
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• pp.424-431
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• 2017

Objective: Study on the application of high pressure processing (HPP) for dark-firm-dry (DFD) beef was conducted to observe whether HPP has any impact on physical properties and to evaluate oxidative deterioration during refrigerated storage under vacuum. Methods: The longissimus lumborum muscles obtained from Friesian Holstein steers ($33{\pm}0.5$ months old) with 24-h postmortem pH higher than 6.0 were vacuum-packed and subjected to pressurization at 200, 400, and 600 MPa for 180 s at $15^{\circ}C{\pm}2^{\circ}C$; the samples were then stored for 9 days at $4^{\circ}C{\pm}1^{\circ}C$ and compared with control (0.1 MPa). Results: HPP increased meat pH by 0.1 to 0.2 units and the tenderness of cooked DFD beef significantly with no significant effects on meat texture profile. The stability of meat pH was well maintained during refrigerated storage under vacuum. No clear effects were found on the activity of catalase and superoxide dismutase, however, glutathione peroxidase activity was significantly reduced by high pressure. HPP and storage time resulted in aroma changes and the increasing amount of malondialdehyde and metmyoglobin relative composition. Conclusion: Although the increasing amount of malondialdehyde content, metmyoglobin formation and aroma changes in HPP-treated samples could not be avoided, HPP at 200 MPa increased $L^*$ and $a^*$ values with less discoloration and oxidative deterioration during storage.

• Restorative Dentistry and Endodontics
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• 제24권4호
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• pp.535-545
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• 1999

Crease of Streptococcus salivarius is believed to play a critical role in bacterial ecology and pH homeostasis in the mouth, and consequently affect the pathogenesis of dental caries and periodontal diseases. Expression of the urease gene is greatly enhanced by low p. f. excess of Carbohydrate, and faster growth. It was observed that urease activity of the strains of S. salivarius that exhibited no of low urease activity was not increased even in low pH condition. In this study, it was hypothesized that the urease gene of the strains is absent, defected, or greatly changed by genetic combination. In order to prove this hypothesis, chromosomes were obtained from 28 S. salivarius strains which had been isolated from normal teeth and carious lesions, subjected to polymerase chain reaction (PCR) using primers encoding highly conserved sequence from ureC, and then the obtained PCR products were compared. The results were as follows: 1. After PCR the strains generated either one of 0.54- and 1.3-kbp PCR products, or none. 2. All 16 strains having a higher urease activity(<50${\mu}mol/min/mg$) produced 0.54-kbp PCR products. 3. Twelve strains without urease activity and with a lower urease activity(<50${\mu}mol/min/mg$) yield either one of 0.54 and 1.3-kbp PCR products, or none. 4. The DNA sequence of the 0.54-kbp PCR product (pCAP-0.54) exhibited 95% identity to the ureC of S. salivarus 57.I; 30bp were found to be different, which led to difference of only 2 amino acids in the sequence. 5. The DNA sequence of the 1.3-kbp PCR product(pCAP-1.3) was found to be highly homologous to the aminopeptidase C gene of Streptococcus thermophilus. Overall results indicate that there are considerable variations of the urease genes from S. salivarus strains and the variations may affect the uncolytic activity of the bacteria directly of indirectly.

• Bulletin of the Korean Chemical Society
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• 제15권11호
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• pp.961-966
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• 1994

Oligomerization of phenylacetylene is catalyzed by $Rh(ClO_4)(CO)(PPh_3)_2$ (Rh-1), $[Rh(CO)(PPh_3)_3]ClO_4$ (Rh-2), $[Rh(COD)L_2]ClO_4 (L_2=(PPh_3)_2$, Rh-3; $(PPh_3)(PhCN)$, Rh-4; $(PhCN)_2$, Rh-5), $[Rh(C_3H_5)(Cl)(CO)(SbPh_3)_2]ClO_4$ (Rh-6), $[Ir(COD)L_2]ClO_4 (L_2=(PPh_3)_2$, $Ir-1; (PPh_3)(PhCN)$, $Ir-2; (PhCN)_2$, Ir-3; (AsPh_3)(PhCN)$, $Ir-4; Ph_2PCH_2CH_2PPh_2$, Ir-5; COD, Ir-6 and 2,2'-dipyridyl, Ir-7), $Ir(ClO_4)(CO)(PPh_3)_2$, $Ir-8, [Ir(PhCN)(CO)(PPh_3)_2]ClO_4$, Ir-9 to produce dimerization products, 1,3-diphenylbut-1-yn-3-ene, 1, (E)-1,4-diphenylbut-1-yn-3-ene, 2 and (Z)-1,4-diphenylbut-1-yn-3-ene, 3, and cyclotrimerization products, 1,3,5-triphenylbenzene, 4 and 1,2,4-triphenylbenzene, 5. Product distribution of the oligomers varies depending on various factors such as the nature of catalysts, reaction temperature, counter anions and excess ligand present in the reaction mixtures. Increasing reaction temperature in general increases the yield of the cyclotrimerization products. Exclusive production of dimer 1 and trimer 4 can be obtained with Ir-1 at 0 $^{\circ}$C and with Ir-2 in the presence of excess PhCN (or $CH_3CN$) at 50 $^{\circ}$C, respectively. Dimer 2 (up to 81%) and trimer 5 (up to 98%) are selectively produced with Rh-1 at 50 and 100 $^{\circ}$C respectively. Production of 3 is selectively increased up to 85% by using $PF_6$- salt of $[Ir(COD)(PPh_3)_2]$+ at 25 $^{\circ}$C. Addition of $CH_3I$ to Rh-1 produces $CH_3PPh_3^+I-$ and increases the rate of oligomerization(disappearance of phenylacetylene). Among the metal compounds investigated in this study, Ir-1 catalyzes most rapidly the oligomerization where the catalytically active species seems to contain lr(PPh3)2 moiety. The stoichiometric reaction of phenylacetylene wth Ir-9 at 25 $^{\circ}$C quantitatively produces hydridophenyl-ethynyl iridium(III) complex, $[lr(H)(C{\equiv}CPh)(PhCN)(CO)(PPh_3)_2]ClO_4$ (Ir-11), which seems to be an intermediate for the oligomerization.

• Kyungpook Mathematical Journal
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• 제47권2호
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• pp.203-219
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• 2007

We estimate the stable rank and connected stable rank of group $C^*$-algebra of certain disconnected solvable Lie groups such as semi-direct products of connected solvable Lie groups by the integers.

• Korean Journal of Pharmacognosy
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• 제4권2호
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• pp.63-65
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• 1973

A component, $C_{20}H_{32}O_3$, m.p. $207.5^{\circ}$, was isolated from Siegesbeckia pubescens $M_{AKINO}$. This compound was identified as $17-hydroxy-16{\beta}-(-)-kauran-19-oic\;acid$, using spectroscopies and synthesizing various derivatives of the compound.

• Korean Journal of Pharmacognosy
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• 제43권2호
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• pp.127-136
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• 2012

Eight flavonoids were isolated from the BuOH fraction of the 70% EtOH extract of Zizyphus jujuba var. spinosa seeds along with three known compounds, daucosterol (1), butyl ${\beta}$-D-fructofuranoside (2), and magnoflorine (4). On the basis of spectroscopic methods and comparison with literature values their structures were elucidated as 6"'-feruloylspinosin (3), nicotiflorin (5), 6"'-p-coumaroylspinosin (6), isospinosin (7), 6"'-vanilloylspinosin (8), spinosin (9), hovetrichoside C (10), and camelliaside B (11). Compounds 1, 2, 10, and 11 were isolated from this plant for the first time.