• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.641-646
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• 2012

We used the hybrid density-functional (B3LYP/6-31G(d,p)) method to analyze the substitution patterns of $C_{20}H_{18}X_2$ derivatives (X = F, Cl, Br, or OH) obtained as disubstituted $C_{20}H_{20}$ cages. Our results suggest that the cis-1 regioisomers (1,2-dihalo derivatives) are less stable than the trans-1 regioisomers (1,20-dihalo derivatives), whereas in the case of the dihydroxy derivatives, the cis-1 regioisomer is more stable than the trans-1 regioisomer. This implies that in the dihalo-induced strain cages of $C_{20}H_{18}X_2$, the strain effect would affect the relative energies, while in the dihydroxide, the hydrogen bonds have a stronger effect on the relative energies in cis-1 regioisomer than the strain effect do. Thus this supports the experimental result in which the bisvicinal tetrol was of particular preparative-synthetic interest as a substitute for the lacking bisvicinal tetrabromide. Further, the topologies of the HOMO and LUMO characteristics of all $C_{20}H_{18}Cl_2$ and $C_{20}H_{18}Br_2$ regioisomers with the same symmetry are same, but they are different from those of $C_{20}H_{18}F_2$ and $C_{20}H_{18}(OH)_2$. This indicates that the five regioisomers of each $C_{20}H_{20}$ disubstituted derivative will have an entirely different set of characteristic chemical reactions.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.231-237
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• 2009

Trans free margarine stock (TFMS) was produced by lipase-catalyzed synthesis of fully hydrogenated soybean oil (FHSBO), avocado oil (AO) and palm oil (PO). A blend of FHSBO, AO, and PO with a 1:5:4 (30:150:120 g, respectively) ratio was interesterified with lipozyme RM IM(from Rhizomucor miehei) in a 1 L-batch type reactor at 65 for 12 hr, and the physicochemical and melting properties of TFMS were compared with commercial margarine. The solid fat content (%) of the TFMS was analyzed at 25, 30, and $35^{\circ}C$, respectively, while its melting point was $37.8^{\circ}C$. The trans fatty acid content of the TFMS was below 0.1%. It also had acid, saponification, and iodine values of 0.4, 173.9, and 58.6, respectively. In HPLC chromatograms of the TFMS, newly synthesized peaks of triacylglycerol molecules were observed by using reverse-phase HPLC with evaporative light-scattering detection. Normal-phase HPLC with UV detection was used to quantify tocopherols in the TFMS, indicating that its ${\alpha}-$, ${\gamma}-$ and ${\delta}$-tocopherol contents were 5.7, 2.1, and 1.7 mg/100 g, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.3
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• pp.399-405
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• 1996

The effects of stearic(18 : 0, SA), oleic(18 : 1 cis, OA) and elaidic acid(18 : 1 trans, EA) on the cell growth, contents of cellular lipids, and the fatty acid composition of cellular and medium lipids in Hep-G$_2$cells were evaluated. The cells were incubated in serum-free medium containing 25, 50, 100 and 200$\mu$M of a fatty acid combined with albumin for 2 days. The fatty acid concentration up to 100$\mu$M showed the normal growth, but the cell growth decreased in the presence of 200$\mu$M fatty acid. The treatment of cells with 100$\mu$M of a fatty acid for two days significantly(p<0.05) increased the cellular triglyceride(TG) content in all fatty acid groups compared to control, but TG contents was not significantly different among all treatment group, but total cholesterol(TC) was the highest level in EA group. The level of free cholesterol(FC) and cholesteryl ester(CE) was similar to those of TC in all fatty acid treated group. The cellular phospholipid(PL) contents were similar between the control and all fatty acid groups. The treatment of cells with SA has no notable effects on the fatty acid composition of TG, CE and PL. The OA treatment caused significant increases in CE(51.2%) and PL(29.8%), but not in TG. The EA treatment resulted in 10.1, 10.7 and 7.8% of $C_{18:1\;trans}$ content in cellular TG, CE, and PL. The TG, CE and PL of medium were relatively similar between SA and OA groups. In EA treated group, TG, CE and PL of medium contained 17.0%, 0.7% and 5.6% of $C_{18:1\;trans}$, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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• pp.679-683
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• 2006

A feeding trial was conducted with 10 sheep for 12 weeks to examine the effect of soybean oil (SBO) supplementation on long-chain fatty acids composition, especially cis9,trans11-conjugated linoleic acid (c9,t11-CLA) in fat tissues. Sheep were fed either a SBO supplemented diet (5%, DM basis) or a control diet without SBO. Chopped rye grass hay was fed as roughage. Concomitant increases in contents of total cholesterol (T-C) and HDL-cholesterol (HDL-C) in the plasma of sheep were observed from the SBO supplementation. The supplementation of SBO reduced (p<0.05) the proportions of $C_{16:1}$, $C_{17:0}$ and $C_{17:1}$ but increased (p<0.05) the proportions of $C_{18:0}$ and octadecenoic acid (t11-$C_{18:1}$) in the intramuscular fat. The $C_{18:0}$ proportion only in the subcutaneous fat was increased (p<0.05) by the SBO supplementation. The SBO supplementation slightly increased CLA proportion in the intramuscular fat and subcutaneous fat.

• The Korean Journal of Food And Nutrition
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• v.15 no.2
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• pp.104-111
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• 2002

The peptidyl prolyl sis-trans isomerase (PPIase, EC 5.2.1.8) from bacillus stearothermophilus was extracted from the cells treated with by lysozyme. PPIase was purified from the cell extracts by heat treatment, ammonium sulfate precipitation, ion exchange chromatography and finally gel filtration, sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE). The molecular weight of the purified PPIase was estimated as 18kDa by SDS-PAGE. The 39 amino acid residues from the N-terminus were determined by the protein sequencer. The enzyme showed the optimum pH at 8.0 and was stable at the range of pH 7.0∼8.0. The enzyme was considerably stable after heat treatment at 60$\^{C}$ for 30minutes, and the enzyme was quite stable up to 65$\^{C}$. The presence of the PPIase in the refolding solution accelerated the isomerization rate of the assay peptide. PPIase gene of Bacillus stearothermophilus was screened from a genomic library by plaque hybridization using the A-l primer as a probe. A PPIase positive plaque contained a 3.0kb insert of the chromosomal DNA. A 3.0kb fragment was subcloned into pUC18, resulting pPI-40. A DNA fragment encoding the N-terminal portion of the PPIase in pPI-40 was amplified by polymerase chain reaction(PCR) method using the A-1 and B-2 primers. The amplified fragment was cloned into the Sma I site of pUC18 and recombinant plasmid was designated as pSN-18. The nucleotide sequence of 167bp fragment was determined. The deduced amino acid sequence of PPIase was completely matched with the determined N-terminal amino acid sequence of PPIase B. stearothermophilus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1328-1334
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• 2010

Low-trans spread fat (LTSF) was produced by lipase-catalyzed synthesis of canola (CO) and fully hydrogenated soybean oil (FHSBO) at 65:35 (w/w). Blend of CO and FHSBO with 65:35 ratio was interesterified using Lipozyme TLIM (immobilized Thermomyces lanuginosus, 20% of total substrate) in a 1 L-batch type reactor at $70^{\circ}C$ with 500 rpm for 24 hr. Then, physicochemical melting properties of LTSF were compared with commercial spread fat. At $20^{\circ}C$, solid fat contents (SFC) of commercial spread fat as a control and LTSF were similar, showing 19.1 and 18.1%, respectively. Major compositional fatty acids of LTSF were C18:0, C18:1 and C18:2 (29.2, 41.8 and 13.3 wt%, respectively). Trans fatty acid content of the LTSF (0.2 wt%) was lower than that of commercial spread fat (5.5 wt%). In the RP-HPLC analysis from LTSF, major triacylglycerol (TAG) molecules were SOL (stearoyl-oleoyl-linoleyl), SOO, POS/PSP, and SOS. Also, polymorphic form and x-ray diffraction of LTSF showed coexistence of $\beta$' and $\beta$ form crystals.

• Journal of Animal Science and Technology
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• v.48 no.6
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• pp.847-860
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• 2006

This study investigated the effects of feeding Charolais steers on diets rich in either n-6 or n-3 polyunsaturated fatty acids (PUFA) and time on feed (TOF) on muscle fatty acid composition and content. Twenty eight steers were fed on ad libitum forage and one of two concentrates varying in the source of fat; soya (high in C18:2 n-6) or whole linseed (high in C18:3 n-3) for either 60 or 90 days in IGER (Institute of Grassland and Environmental Research, UK). The concentrates were fed at approximately 0.73 of total DM intake. TOF influenced carcass weight, conformation and fatness scores, which were higher at 90 v. 60 days (P<0.05). Diet did not affect total fatty acid content of neutral lipid in m. longissimus thoracis but feeding linseed increased total phospholipid fatty acid by approx- imately 15%(P<0.05). Linseed increased the amount and proportion of C18:3 n-3 (P<0.001) and the proportion of CLA (cis-9, trans-11 conjugated linoleic acid), while soya increased the content (P<0.05) and proportion (P<0.001) of C18:2 n-6 in muscle neutral lipid. In muscle phospholipid, linseed significantly increased the amount of CLA, C18:3 n-3 and its longer chain derivatives as well as C14:0, C16:0, C18:0. C18:1 trans and C18:2 n-6. The amount and proportion of C18:2 n-6 and its longer chain C20 derivatives were higher on feeding soya. TOF (90 v. 60 day) increased the content of C14:0, C16:0, C16:1, CLA, C18:1 n-9, C18:2 n-6 and C18:3 n-3 in muscle neutral lipid. The P:S was not affected by diet or TOF. The ratio of C18:2 n-6 : C18:3 n-3 and sum of n-6 : n-3 fatty acids were higher in muscle from animals fed on linseed v. soya (P<0.001). The study indicates that the PUFA composition of beef muscle may be significantly modified by feeding contrasting dietary lipids, soya vs. linseed. Feeding linseed produced a better balance of muscle fatty acids, more in line with current nutritional recommendations with a lower C18:2 n-6:C18:3 n-3 ratio associated with higher muscle content of C18:3 n-3 and C20:5 n-3 and CLA and lower C20:4 n-6.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.617-626
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• 2003

This experiment employed a rumen simulated continuous culture system to examine the possibility of improving the rumen bypass of polyunsaturated fatty acids (PUFA) by using a high proportion of concentrate in the feed, and compared soya and linseed in terms of conjugated linoleic acid (CLA) production. No effect of type of fat source was observed on ruminal fermentation. A high proportion of concentrate (80%) in the feed decreased (P<0.001) vessel pH but increased (P<0.01) ammonia nitrogen, total VFA, acetate, butyrate and valerate concentrations compared with a low proportion (40%). Fat sources (soya vs. linseed) and concentrate ratio in the feed did not affect digestibilities of organic matter (OM), total nitrogen, neutral detergent fiber (NDF) and acid detergent fiber (ADF). Soya increased the flows of trans C18:1, C18:2 n-6 and C18:3 n-3 compared with linseed. The difference in fat source alone did not affect the flow of CLA but this was increased when high levels of soya and linseed were associated with a high proportion of concentrate in the feed. There was no effect of fat source on biohydrogenation of C18:1 n-9 and C18:2 n-6, but biohydrogenation of C18:3 n-3 and total C18 PUFA was higher with the linseed than with the soya treatment. A high proportion of concentrate decreased biohydrogenation of C18:2 n-6, C18:3 n-3 and total C18 PUFA compared with a low proportion.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1743-1748
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• 2003

The effect of pH on the fermentation characteristics and the formation of cis-9, trans-11 conjugated linoleic acid (CLA) and trans-11 octadecenoic acid by mixed ruminal bacteria was examined in vitro when incubated with linseed or rapeseed. Concentrate (1%, w/v) with ground linseed (0.6%, w/v) or rapeseed (0.5%, w/v) was added to 600 ml mixed solution of strained rumen fluid with artificial saliva (1:1, v/v), and was incubated anaerobically for 12 h at $39^{\circ}C$. The pH of culture solution was maintained at level close to 4.5, 5.3, 6.1 and 6.9 with 30% $H_2SO_4$ or 30% NaOH solution. pH increment resulted in increases of ammonia and total volatile fatty acid (VFA) concentration in culture solutions containing both oilseeds. Fermentation did not proceeded at pH 4.5. Molar proportion of acetate decreased but that of propionate increased as pH increased when incubated with oilseeds. While the hydrogenating process was very slow at the pH range of 4.5 to 5.3, rapid hydrogenation was found from the culture solutions of pH 6.1 and 6.9 when incubated with linseed or rapeseed. As pH in culture solution of linseed or rapeseed increases proportions of oleic acid (cis-9 $C_{18:1}$) and trans-11 octadecenoic acid increased but those of linoleic acid and linolenic acid decreased. The CLA proportion increased with pH in culture solution containing rapeseed but CLA was mostly not detected from the incubation of linseed.

• Journal of the Korean Chemical Society
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• v.33 no.2
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• pp.247-256
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• 1989

4-Acetyl-5,6-dihydro-2-methyl-1,4-thiazine carboxylic acid derivatives 24 were prepared by ring expansion of corresponding thiazolidine sulfoxides. Oxidation of 2-methyl-1,3-thiazolidine-2-acetic acid derivatives 12 gave a mixture of cis and trans sulfoxides, 14 and 15. Assignments of the cis and trans sulfoxides were based on the $^1HNMR$ and IR spectroscopy and regioselectivity of deuterium exchange reaction. With PTSA as acid catalyst both the cis and trans sulfoxide, 14 and 15 were transformed via sulfenic acid 18 to dihydro-1,4-thiazine 24. However, under the neutral conditions (in DMF at $100^{\circ}C$) the trans sulfoxides 15 rearranged via sulfenic acid 21 to isomeric dihydrothiazines 27. The mechanism of formations of 24 and 27 is also discussed.