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1.
The autoxidation processes of the cis-9,trans-11 (c9,t11) and trans-10,cis-12 (t10,c12) isomers of CLA were separately observed at ca. 0% RH and different temperatures. The t10,c12 CLA oxidized faster than the c9,t11 isomer at all tested temperatures. The first half of the oxidation process of t10,c12 CLA obeyed an autocatalytic-type rate expression, but the latter half followed first-order kinetics. On the other hand,
the entire oxidation process of c9,t11 CLA could be expressed by the autocatalytic-type rate expression. The apparent activation energies and frequency factors
for the autoxidation of the isomers were estimated from the rate constants obtained at various temperatures based on the Arrhenius
equation. The apparent activation energies for the CLA isomers were greater than those for the nonconjugated n−6 and n−3 PUFA
or their esters. However, the enthalpyentropy compensation held during the autoxidation of both the CLA and PUFA. This suggested
that the autoxidation mechanisms for the CLA and PUFA were essentially the same. 相似文献
2.
The objective of the present study was to compare the effects of cis-9,trans-11 + trans-8,cis-10 conjugated linoleic acid (CLA) mixture to those of cis-9,trans-11 + trans-10,cis-12 CLA mixture and linoleic acid (LA) on lipoprotein profile, hepatic lipids, body composition and digestibility of dietary
fat in hamsters (n = 17) fed diets containing 2% of experimental fat (w/w) for 28 days. The cis-9,trans-11 + trans-10,cis-12 CLA mixture showed higher LDL cholesterol concentrations than LA and the cis-9,trans-11 + trans-8,cis-10 CLA mixture. The cis-9,trans-11 + trans-8,cis-10 CLA mixture induced similar plasma LDL cholesterol and hepatic lipid concentrations, and coefficient of digestibility
as LA, indicating no effect of the trans-8,cis-10 CLA isomer on these lipid parameters. On the other hand, the cis-9,trans-11 + trans-8,cis-10 CLA mixture induced higher plasma VLDL cholesterol and triglycerides than LA and the cis-9,trans-11 + trans-10,cis-12 CLA mixture. The cis-9,trans-11 + trans-8,cis-10 CLA mixture also induced the highest plasma glucose concentrations compared with the two other groups, indicating an impairment
of glycemic control. No differences in body composition were noted between the three groups. The present results thus show
that the cis-9,trans-11 + trans-8,cis-10 CLA mixture can deteriorate plasma VLDL cholesterol and triglycerides in hamsters, possibly due to an increased flux of
glucose. 相似文献
3.
Endothelial cell function can be influenced by nutrition, especially dietary FA and antioxidants. One class of dietary FA
that is found in meat and dairy products derived from ruminant animals is conjugated linoleic acids (CLA). We have examined
the effects of several CLA isomers on endothelial cell proliferation. 9t,11t-CLA was the only isomer that inhibited bovine arotic endothelial cell (BAEC) [3H]methylthymidine incorporation (I50=35 μM), and this antiproliferative effect was time-dependent. A small decrease (20%) in cell number was observed only at
the highest concentration (60 μM) tested. The 9c,11t-, 9c,11c-, 10t 12c-, and 11c,13t-CLA isomers did not exhibit any antiproliferative effects over a 5–60 μM concentration range. α-Tocopherol and BHT decreased
BAEC proliferation, but pretreatment of cells with either of these antioxidants substantially attenuated the antiproliferative
effect of 9t,11t-CLA. No difference in lipid peroxidation, as measured by the thiobarbituric acid assay for malondialdehyde, was observed
on treatment of endothelial cells with either 9t,11t- or 9c,11t-CLA. However, a 43% increase in caspase-3 activity was observed after incubating BAEC with 9t,11t-CLA, suggesting that the antiproliferative effect of this isomer is partially due to an apoptotic pathway. In contrast to
the above results with normal endothelial cells, these five CLA isomers all inhibited proliferation of the human leukemic
cell line THP-1, with the 9t,11t isomer again being the most (I50=60 μM) effective. These results confirm that different CLA isomers have different inhibitory potencies on the proliferation
of normal and leukemic cells. 相似文献
4.
Malpuech-Brugère C Mensink RP Loreau O Maret A Fernie CE Lassel TS Chardigny JM Scrimgeour CM Sébédio JL Beaufrère B 《Lipids》2010,45(11):1047-1051
Few studies report the individual effect of 9c,11t- and 10t,12c-CLA on human energy metabolism. We compared the postprandial oxidative metabolism of 9c,11t- and 10t,12c-CLA and oleic acid (9c-18:1) in 22 healthy moderately overweight volunteers. After 24 weeks supplementation with 9c,11t-, 10t,12c-CLA or 9c-18:1 (3 g/day), subjects consumed a single oral bolus of the appropriate [1-13C]-labeled fatty acid. 8 h post-dose, cumulative oxidation was similar for 9c-18:1 and 10t,12c (P = 0.66), but significantly higher for 9c,11t (P < 0.01). 相似文献
5.
6.
The supplementation of conjugated linoleic acid (CLA) has been shown to improve endurance by enhancing fat oxidation during exercise in rodents and humans. This study was designed to investigate the isomer-specific effects of CLA on endurance capacity and energy metabolism in mice during exercise. Male 129Sv/J mice were divided into three dietary groups and fed treatment diet for 6 weeks; control, 0.5 % cis-9,trans-11 (c9,t11) CLA, or 0.5 % trans-10,cis-12 (t10,c12) CLA. Dietary t10,c12 CLA induced a significant increase in maximum running time and distance until exhaustion with a dramatic reduction of total adipose depots compared to a control group, but there were no significant changes in endurance with the c9,t11 CLA treatment. Serum triacylglycerol and non-esterified fatty acid concentrations were significantly lower in the t10,c12 fed mice after exercise compared to control and the c9,t11 CLA fed-animals. Glycogen contents in livers of the t10,c12 fed-mice were higher than those in control mice, concomitant with reduction of serum l-lactate level. There were no differences in non-exercise physical activity among all treatment groups. In addition, the mRNA expression levels of carnitine palmitoyl transferase 1β, uncoupling protein 2 and peroxisome proliferator-activated receptor δ (PPARδ) in skeletal muscle during exercise were significantly up-regulated by the t10,c12 CLA but not the c9,t11 CLA. These results suggest that the t10,c12 CLA is responsible for improving endurance exercise capacity by promoting fat oxidation with a reduction of the consumption of stored liver glycogen, potentially mediated via PPARδ dependent mechanisms. 相似文献
7.
Da Xu Lijuan Sun Huayong Chen Dongming Lan Yonghua Wang Bo Yang 《Journal of the American Oil Chemists' Society》2012,89(7):1259-1266
Diacylglycerols (DAG) of conjugated linoleic acid (CLA) were prepared by esterification of glycerol with fatty acids enriched with CLA (FFA–CLA, >95%) in the presence of a novel lipase from Malassezia globosa (SMG1). Lipase SMG1 is strictly specific to mono- and diacylglycerols but not triacylglycerols, which is similar to the properties of lipase from Penicillium camembertii (lipase G 50), but lipase SMG1 showed preference on the production of DAG with the reaction proceeding. Low temperature was beneficial for the conversion of FFA–CLA into acylglycerols, the degree of esterification reached 93.0% when the temperature was 5 °C. The maximum DAG content (53.4%) was achieved at 25 °C. The rate of DAG synthesis increased as the enzyme loading increased. However, at lipase amounts above 240 U/g mixtures, no significant increases in DAG concentration were observed. The molar ratio of FFA–CLA to glycerol and initial water content were optimized to be 1:3 (mol/mol) and 3%. Lipase SMG1 showed no regioselectivity because the contents of 1,3-DAG and 1,2-DAG were 43.1% and 21.2% based on total content of acylglycerols. By calculating the ratio of 9c, 11t-CLA to 10t, 12c-CLA, it was indicated that lipase SMG1 showed a little preference to 10t, 12c-CLA at the sn-1(3) position of monoacylglycerols (MAG), while no selectivity for 9c, 11t-CLA at the sn-2 position of DAG was obviously found. 相似文献
8.
Isomeric CLA exhibit several significant biological activities in animals and humans and are easily isomerized to their corresponding
t,t-CLA isomers during methylation with various acid-catalyzed reagents. To minimize such isomerization and provide a valid quantification
of human plasma CLA content, several methylation methods were tested. Plasma neutral lipid, nonesterified FA (NEFA), and polar
lipid classes were separated into the following fractions: (i) cholesteryl ester (CE, 1.2 mg/12 mL, 37.5% lipids), (ii) TAG
(0.8 mg/12 mL, 25% lipids), (iii) NFFA (0.2 mg/12 mL, 6.2% lipids), (iv) MAG/DAG/cholesterol (0.3 mg/12 mL, 9.4% lipids),
and (v) phospholipid (PL, 0.5 mg/20 mL, 15.6% lipids). Data showed that c9,t11-CLA found in TAG, MAG/DAG/cholesterol, and PL fractions were converted to methyl esters with sodium methoxide within 2
h at 55°C. However, the c9,t11-CLA in the CE fraction could not be completely converted to methyl esters by sodium methoxide/acetylchloride in methanol
or methanolic KOH; instead, CE was treated with sodium methoxide and methyl acetate in diethyl ether for 1 h. NEFA were converted
to methyl esters with trimethylsilyldiazomethane (TMSDAM). All reaction mixtures were monitored by TLC prior to GLC analysis.
The highest enrichment of c9,t11-18∶2 (% FA) was in TAG (0.31%), followed by CE (0.14%) and PL (0.13%). The above methylation methods were then applied
to a small subset (n=10) of nonfasting plasma lipid fractions to confirm the applicability of these data. Results from this subset of samples
also indicated that the greatest enrichment of c9,t11-CLA was present in the TAG fraction (0.39%), followed by CE (0.27%) and PL (0.22%). These data indicate that different
plasma fractions have different c9,t11-CLA contents. 相似文献
9.
Three Hen Strains Fed Photoisomerized <Emphasis Type="Italic">trans,trans</Emphasis> CLA-Rich Soy Oil Exhibit Different Yolk Accumulation Rates and Source-Specific Isomer Deposition
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Most CLA chicken feeding trials used cis,trans (c,t) and trans,cis (t,c) CLA isomers to produce CLA‐rich eggs, while reports of trans,trans (t,t) CLA enrichment in egg yolks are limited. The CLA yolk fatty acid profile changes and the 10–12 days of feeding needed for maximum CLA are well documented, but there is no information describing CLA accumulation during initial feed administration. In addition, no information on CLA accumulation rates in different hen strains is available. The aim of this study was to determine a mathematical model that described yolk CLA accumulation and depletion in three hen strains by using t,t CLA‐rich soybean oil produced by photoisomerization. Diets of 30‐week Leghorns, broilers, and jungle fowl were supplemented with 15 % CLA‐rich soy oil for 16 days, and eggs were collected for 32 days. Yolk fatty acid profiles were measured by GC‐FID. CLA accumulation and depletion was modeled by both quadratic and piecewise regression analysis. A strong quadratic model was proposed, but it was not as effective as piecewise regression in describing CLA accumulation and depletion. Broiler hen eggs contained the greatest concentration of CLA at 3.2 mol/100 g egg yolk, then jungle fowl at 2.9 mol CLA, and Leghorns at 2.3 mol CLA. The t,t CLA isomer levels remained at 55 % of total yolk CLA during CLA feeding. However, t‐10,c‐12 (t,c) CLA concentration increased slightly during CLA accumulation and was significantly greater than c‐9,t‐11 CLA. Jungle fowl had the smallest increase in yolk saturated fat with CLA yolk accumulation. 相似文献
10.
Furan fatty acids (furan-FA) can be formed by auto-oxidation of conjugated linoleic acids (CLA) and may therefore be ingested
when CLA-containing foodstuff is consumed. Due to the presence of a furan ring structure, furan-FA may have toxic properties,
however, these substances are toxicologically not well characterized so far. Here we show that 9,11-furan-FA, the oxidation
product of the major CLA isomer cis-9,trans-11-CLA (c9,t11-CLA), is not toxic to human intestinal Caco-2 cells up to a level of 100 μM. Oil-Red-O staining indicated
that 9,11-furan-FA as well as c9,t11-CLA and linoleic acid are taken up by the cells and stored in the form of triglycerides
in lipid droplets. Chemical analysis of total cellular lipids revealed that 9,11-furan-FA is partially elongated probably
by the enzymatic activity of cellular fatty acid elongases whereas c9,t11-CLA is partially converted to other isomers such
as c9,c11-CLA or t9,t11-CLA. In the case of 9,11-furan-FA, there is no indication for any modification or activation of the
furan ring system. From these results, we conclude that 9,11-furan-FA has no properties of toxicological relevance at least
for Caco-2 cells which serve as a model for enterocytes of the human small intestine. 相似文献
11.
Synthesis and Structural Analysis of Structured Triacylglycerols with CLA Isomers in the <Emphasis Type="Italic">sn</Emphasis>-2- Position 总被引:1,自引:1,他引:0
Francesca Blasi Lina Cossignani Ancilla Bosi Silvia Maurelli Gilda D’Arco Dennis Fiorini Maria Stella Simonetti Pietro Damiani 《Journal of the American Oil Chemists' Society》2008,85(7):613-619
The present research deals with the chemical esterification of the sn-2- position of sn-1,3-diacylglycerol (sn-1,3-DAG) with 9cis,11trans (c9,t11) and 10trans,12cis (t10,c12) conjugated linoleic acid (CLA) isomers to obtain structured triacylglycerols (TAG); the sn-1,3-DAG substrates were produced from extra virgin olive oil by means of enzymatic reactions while CLA isomers were obtained
using a three-step procedure based on alkaline hydrolysis of sunflower oil, urea purification of linoleic acid (LA) and alkaline
isomerization of LA. The results showed good levels of CLA incorporation in structured TAG at the tested temperatures: 37.5%
at 4 °C and 39.1% at 14 °C. To evaluate the incorporation of CLA isomers in sn-2- position of sn-1,3-DAG structural analysis of the newly synthesized TAG was carried out using an enzymatic and a chemical method. The results
of the structural analysis also showed up the occurrence of acyl migration. The pancreatic lipase method allowed the direct
determination of the fatty acid composition of TAG sn-2- position but this enzymatic method showed different results (p < 0.05) in respect to the chemical one; this occurrence could be due to an acylic specificity of the lipase. High incorporation
of CLA isomers in sn-2- position of TAG was observed, 77.0% at 4 °C and 81.5% at 14 °C, considering the results of the chemical procedure. 相似文献
12.
The yeast Saccharomyces cerevisiae was cultivated in the presence of free CLA that was either a pure trans-10, cis-12 isomer, a pure cis-9, trans-11 isomer, or a 1∶1 mixture of the two, and the influence of these supplementations on the content and FA composition of
the lipids in the yeast was determined. Neither the pure isomers nor their 1∶1 mixture influenced the growth of the yeast,
but the trans-10, cis-12 isomer reduced the amount of cellular lipids by 40%. The reduction in total cellular lipids by the trans-10, cis-12 CLA was due to a reduction in TAG. Both of the isomers were incorporated into the yeast lipids, reaching a proportion
of about 33% in TAG. With the incorporation of CLA, the yeast reduced the amount and desaturation of endogenously synthesized
FA. These clear and pronounced isomer-specific effects of CLA on the yeast suggest that yeast might be a useful model to obtain
a more comprehensive view of the mechanisms of the action of CLA on lipid metabolism. 相似文献
13.
Yomi?Watanabe Yoshie?Yamauchi-Sato Toshihiro?Nagao Satoshi?Negishi Tadamasa?Terai Takashi?Kobayashi Yuji?Shimada
Production of MAG with CLA using Penicillium camembertii mono- and diacylglycerol lipase (referred to as lipase) was attempted for the purpose of expanding the application of CLA.
The commercial product of CLA (referred to as FFA-CLA) is a FFA mixture containing almost equal amounts of 9cis,11trans (9c,11t)-CLA and 10t,12c-CLA. Esterification of FFA-CLA with glycerol without dehydration achieved 84% esterification but produced almost equal amounts
of MAG and DAG. Esterification with dehydration not only achieved a high degree of esterification but also suppressed the
formation of DAG. When a mixture of FFA-CLA/glycerol (1∶2, mol/mol), 1% water, and 200 units/g-mixture of P. camembertii lipase was agitated at 30°C for 72 h with dehydration at 5 mm Hg, the degree of esterification reached 95% and the contents
of MAG and DAG were 90 and 6 wt%, respectively. This reaction system may be applied to the industrial production of MAG with
unstable CLA. 相似文献
14.
CLA, defined as one or more octadecadienoic acids (18∶2) with conjugated double bonds, has been reported to be active in a
number of bological systems. GC and silver ion HPLC (Ag+-HPLC) have been the primary techniques for identifying specific CLA isomers in both foods and biological extracts. Recently,
GC relative retention times were reported for all c,c, c/t (c,t and t,c), and t,t CLA FAME from the 6,8- to the 13,15-positions in octadecadienoic acid (18∶2). Presented here is the relative retention order
of the same CLA FAME using Ag+-HPLC with two different elution systems. The first elution system, consisting of 0.1% acetonitrile/0.5% diethyl ether (DE)/hexane,
has been used previously to monitor CLA composition in foods. Also presented here is the retention order of CLA FAME using
2% acetic acid/hexane elution solvent, which has advantages of more stable retention volumes and a complementary elution order
of CLA FAME isomers. The data are reported using retention volumes (RV) adjusted for toluene, an estimator for dead volume,
and relative to c9,t11-18∶2. Measurement of relative RV in the analysis of 88 samples of cow plasma, milk, and rumen fluids using Ag+-HPLC is also presented here. The % CV ranged from 1.04 to 1.62 for t,t isomers and from 0 to 0.48 for c/t isomers. 相似文献
15.
Shen X Nuernberg K Nuernberg G Zhao R Scollan N Ender K Dannenberger D 《Lipids》2007,42(12):1093-1103
The objective of present study was the comparison of trans-11 18:1 (VA) and cis-9,trans-11 CLA concentrations in the rumen and different tissues in beef cattle, and to examine the diet and breed effects on the
compound concentration and deposition. Sixty-four German Holstein and German Simmental bulls were randomly assigned to two
dietary treatments, based on concentrate or pasture. The concentration of cis-9,trans-11 CLA and VA in rumen, duodenal digesta and different tissues was determined by gas chromatography. The results showed that
pasture relative to concentrate feeding significantly increased the concentration of VA in duodenal digesta, plasma and erythrocyte
phospholipids. Pasture-based feeding resulted in a significant enrichment of cis-9,trans-11 CLA in plasma lipids and erythrocyte phospholipids, but not in rumen and duodenal digesta, compared to concentrate-fed
diet. Diet did not affect the cis-9,trans-11 CLA concentrations (mg/100 g fresh tissue) in semitendinosus muscle and subcutaneous fat. There was a breed effect on
the deposition of cis-9,trans-11 CLA in longissimus muscle with lower concentration in pasture-fed German Simmental bulls compared to concentrate-fed bulls.
However, pasture feeding significantly increased both, the VA and cis-9,trans-11 CLA concentrations in liver and heart tissues. Both diet and breed effects on Δ9-desaturase index was observed in muscle and subcutaneous fat tissues. There was a linear relationship between the concentration
of VA and cis-9,trans-11 CLA and the coefficients of determination (R
2) varied between 0.29 and 0.87 from rumen to the different tissues. 相似文献
16.
Docosahexaenoic Acid and Eicosapentaenoic Acid Did not Alter <Emphasis Type="Italic">trans</Emphasis>-10,<Emphasis Type="Italic">cis</Emphasis>-12 Conjugated Linoleic Acid Incorporation into Mice Brain and Eye Lipids
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trans 10,cis 12‐CLA has been reported to alter fatty acid composition in several non‐neurological tissues, but its effects are less known in neurological tissues. Therefore, the purpose of this study was to determine if CLA supplementation would alter brain and eye fatty acid composition and if those changes could be prevented by concomitant supplementation with docosahexaenoic acid (DHA; 22:6n3) or eicosapentaenoic acid (EPA; 20:5n3). Eight‐week‐old, pathogen‐free C57BL/6N female mice (n = 6/group) were fed either the control diet or diets containing 0.5% (w/w) t10,c12‐CLA in the presence or absence of either 1.5% DHA or 1.5% EPA for 8 weeks. CLA concentration was significantly (P < 0.05) greater in the eye but not in the brain lipids of the CLA group when compared with the control group. The sums of saturated, monounsaturated, polyunsaturated fatty acids, and n3:n6 ratio did not differ between these two groups for both tissues. The n3:n6 ratio and concentrations of 20:5n3 and 22:5n3 were significantly greater, and those of 20:4n6, 22:4n6, and 22:5n6 were lesser in the CLA + DHA and CLA + EPA groups than in the control and CLA groups for either tissue. DHA concentration was higher in the CLA + DHA group only but not in the CLA + EPA group when compared with the CLA group for both tissues. The dietary fatty acids generally induced similar changes in brain and eye fatty acid concentration and at the concentrations used both DHA and EPA fed individually with CLA were more potent than CLA alone in altering the tissue fatty acid concentration. 相似文献
17.
Muskox (Ovibos moschatus) are ruminant animals native to the far north and little is known about their fatty acid composition. Subcutaneous adipose
tissue (backfat) from 16 wild muskox was analyzed and compared to backfat from 16 barley fed beef cattle. Muskox backfat composition
differed substantially from beef and the most striking difference was a high content of 18:0 (26.8 vs. 9.77%). This was accompanied
by higher levels of most other saturated fatty acids except beef had more 16:0. Muskox backfat also had a lower level of cis-18:1 and this was related to a lower expression of steroyl-CoA desaturase mRNA. Beef backfat had a higher level of total
trans-18:1 (4.25 vs. 2.67%). The most prominent trans-18:1 isomers in beef backfat were 10t-18:1 (2.13%) and 11t-18:1 (0.77%) whereas the most prominent isomers in muskox backfat were 11t-18:1 (1.41%), 13t/14t- (0.27%) and 16t-18:1 (0.23%). The total conjugated linoleic acid (CLA) content was higher in beef backfat than muskox (0.67 vs. 0.50%) with
9c,11t-18:2 as the most abundant CLA isomer. The second most abundant CLA isomer in beef backfat was 7t,9c-18:2 (0.10%) whereas in muskox it was 11t13c-18:2 (0.04%). Muskox backfat had a higher content of 18:3n-3 and its elongation and desaturation products 20:5n-3, 22:5n-3
and 22:6n-3 and a lower n-6/n-3 ratio. Overall, the high forage diet of muskox seemed to produce a healthier fatty acid profile
and highlighted the need to develop feeding strategies for intensively raising beef that will not negatively impacting fatty
acid composition. 相似文献
18.
Octadecadienoic acids with conjugated double bonds are often referred to as conjugated linoleic acid, or CLA. CLA is of considerable
interest because of potentially beneficial effects reported from animal studies. Analysis of CLA is usually carried out by
GC elution of FAME. If the presence of low-level isomers is of interest, a complementary technique such as silverion HPLC
is also used. These analyses have been hindered by a lack of well-characterized commercially available reference materials.
Described here are the synthesis and isolation of selected 6,8-through 13,15-positional CLA isomers, followed by isomerization
of these CLA isomers with iodine to produce all the possible cis,cis,cis,trans,trans,cis, and trans,trans combinations. Also present are the GC retention times of the CLA FAME relative to γ-linolenic acid (6c,9c,12c-octadecatrienoic acid) FAME using a 100-m CP Sil-88 capillary column (Varian Inc., Lake Forest, CA). These data include all
the CLA isomers that have been identified thus far in foods and dietary supplements and should greatly aid in the future analysis
of CLA in these products. 相似文献
19.
Akinori Ando Jun Ogawa Shigenobu Kishino Taiyo Ito Norifumi Shirasaka Eiji Sakuradani Kenzo Yokozeki Sakayu Shimizu 《Journal of the American Oil Chemists' Society》2009,86(3):227-233
The fatty acid desaturation and elongation reactions catalyzed by Trichoderma sp. 1-OH-2-3 were investigated. This strain converted palmitic acid (16:0) mainly to stearic acid (18:0), and further to
oleic acid (c9-18:1), linoleic acid (c9,c12-18:2), and α-linolenic acid (c9,c12,c15-18:3) through elongation, and Δ9, Δ12, and Δ15 desaturation reactions, respectively. Palmitoleic acid (c9-16:1) and cis-9,cis-12-hexadecadienoic acid were also produced from 16:0 by the strain. This strain converted n-tridecanoic acid (13:0) to cis-9-heptadecenoic acid and further to cis-9,cis-12-heptadecadienoic acid through elongation, and Δ9 and Δ12 desaturation reactions, respectively. trans-Vaccenic acid (t11-18:1) and trans-12-octadecenoic acid (t12-18:1) were desaturated by the strain through Δ9 desaturation. The products derived from t11-18:1 were identified as the conjugated linoleic acids (CLAs) of cis-9,trans-11-octadecadienoic acid and trans-9,trans-11-octadecadienoic acid. The product derived from t12-18:1 was identified as cis-9,trans-12-octadecadienoic acid. cis-6,cis-9-Octadecadienoic acid was desaturated to cis-6,cis-9,cis-12-octadecatrienoic acid by this strain through Δ12 desaturation. The broad substrate specificity of the elongation, and
Δ9 and Δ12 desaturation reactions of the strain is useful for fatty acid biotransformation. 相似文献
20.
Jun Tabata Makoto Minamishima Hajime Sugie Takehiko Fukumoto Fumiaki Mochizuki Yutaka Yoshiyasu 《Journal of chemical ecology》2009,35(2):243-249
We analyzed the sex pheromone of the pear fruit moth, Acrobasis pyrivorella, by means of gas chromatography–electroantennographic detection (GC-EAD) and GC–mass spectrometry. Two EAD-active compounds
were detected in the pheromone gland extract of females. They were identified as (Z)-9-pentadecenyl acetate (Z9-15:OAc) and pentadecyl acetate (15:OAc). The amounts per female gland (mean ± standard error)
of these compounds were 12.9 ± 2.8 and 0.8 ± 0.1 ng, respectively. Synthetic Z9-15:OAc (300 μg) attracted conspecific males
in field trapping experiments. When 15:OAc (21 μg; 7% of Z9-15:OAc quantity) was added, the number of males trapped increased
significantly. Catch in traps baited with the mixture of these compounds was greater than that in traps baited with 1–3-day-old
virgin females. We, therefore, conclude that Z9-15:OAc and 15:OAc are sex pheromone components of this species. 相似文献