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Conjugated Linoleic Acid (conjugated + linoleic_acid)
Selected AbstractsEFFECT OF WATER ACTIVITY ON PHYSICAL PROPERTIES OF CONJUGATED LINOLEIC ACID (CLA) MICROCAPSULESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2010MARIBEL JIMENEZ ABSTRACT The physical properties of spray drying powders must be considered for the design of equipment. Conjugated linoleic acid (CLA) microcapsules were spray dried by using the following as wall materials: whey protein concentrate (WPC), a blend of whey protein concentrate,maltodextrins (WPC-MD) and gum arabic (GA). These were prepared and their physical properties were studied. The bulk density, packed density, particle density, compressibility and color of the microcapsules were evaluated in a range of water activities from 0.108 to 0.898. No significant differences in the physical properties were found when WPC was used as a wall material in the microcapsules stored at the whole range of water activities tested. Maltodextrins conferred changes in some of the physical properties of the microcapsules (WPC-MD) upon storage at high water activities. GA microcapsules showed drastic changes in all physical properties studied at water activities above 0.628. PRACTICAL APPLICATIONS This work shows the best conditions for storing conjugated linoleic acid (CLA) microcapsules elaborated with different wall materials, which have been reported to have a high potential as a food additive because of the nutraceutical properties of CLA. This research should reveal the behavior of water activity during storage on physical properties, and make it possible to predict what characteristics need to be added to a food, besides being important for the design of equipment, packing and transport. [source] Lipase-mediated Acidolysis of Fully Hydrogenated Soybean Oil with Conjugated Linoleic AcidJOURNAL OF FOOD SCIENCE, Issue 1 2004J. Ortega ABSTRACT: Interesterification (acidolysis) of fully hydrogenated soybean oil (melting point = 69.9 °C) with conjugated linoleic acid (CLA) was carried out in a batch reactor at 75 °C. Lipases from Candida antarctica, Rhizomucor miehei, Pseudomonas sp., and Thermomyces lanuginosus were used at 5% (wt/wt) of the total substrate load. The lipase from Rhizomucor miehei produced the fastest reaction rates, and the greatest extent of incorporation of CLA residues in acylglycerols was achieved in 12 h. Lipases from C. antarctica and T. lanuginosus produced slower initial rates, and maximum extents of incorporation of CLA residues were achieved in 24 h. The lipase from Pseudomonas sp. produced the slowest initial rate. The corresponding maximum extent of incorporation was reached in 48 h. Differential scanning calorimetry analysis of the triacylglycerol (TAG) fractions produced by C. antarctica, R. miehei, and T. lanuginosus lipases after purification by solid phase extraction showed little variation in melting point (60.4 °C, 62.8 °C, and 60.1 °C, respectively). By contrast, the corresponding TAG fraction produced by the Pseudomonas sp. lipase melted at 48.4 °C. The positional distribution of the TAGs produced by the lipase from Pseudomonas sp. differed appreciably from those produced by the other enzymes. [source] Bioconversion of Linoleic Acid into Conjugated Linoleic Acid by Immobilized Lactobacillus reuteriBIOTECHNOLOGY PROGRESS, Issue 3 2003Sun-Ok Lee Lactobacillus reuteri was immobilized on silica gel to evaluate the bioconversion of linoleic acid (LA) into conjugated linoleic acid (CLA), consisting of cis -9,trans -11 and trans -10,cis -12 isomers. The amount of cell to carrier, the reaction time, and the substrate concentration, pH, and temperature for CLA production were optimized at 10 mg of cells/(g of carrier), 1 h, 500 mg/L LA, 10.5, and 55 °C, respectively. In the presence of 1.0 mM Cu2+, CLA production increased by 110%. Under the optimal conditions, the immobilized cells produced 175 mg/L CLA from 500 mg/L LA for 1 h with a productivity of 175 mg/(L·h) and accumulated 5.5 times more CLA than that obtained from bioconversion by free washed cells. The CLA-producing ability of reused cells was investigated over five reuse reactions and was maximal at pH 7.5, 25 °C, and 1.0 mM Cu2+. The total amount of CLA by the combined five reuse reactions was 344 mg of CLA/L reaction volume. This was 8.6 times higher than the amount obtained from reuse reactions by free washed cells. [source] PPAR, and PP2A are involved in the proapoptotic effect of conjugated linoleic acid on human hepatoma cell line SK-HEP-1INTERNATIONAL JOURNAL OF CANCER, Issue 11 2007Giuliana Muzio Abstract Conjugated linoleic acid (CLA), found in dairy products, in beef and lamb has been demonstrated to possess anticancer properties protecting several tissues from developing cancer. Moreover, it has been shown to modulate apoptosis in several cancer cell lines. The aim of this study was to investigate which signaling transduction pathways were modulated in CLA-induced apoptosis in human hepatoma SK-HEP-1 cells. The cells exposed to CLA were evaluated for PPAR,, PP2A, pro-apoptotic proteins Bak, Bad and caspases, and anti-apoptotic proteins Bcl-2 and Bcl-XL. Cells were also treated with okadaic acid, a PP2A inhibitor, or with Wy-14643, a specific PPAR, agonist. The CLA-induced apoptosis was concomitant to the increase of percentage of cells in the S phase, PPAR,, PP2A and pro-apoptotic proteins; simultaneously, antiapoptotic proteins decreased. Inhibition of PP2A prevented apoptosis, and PPAR, agonist showed similar effect as CLA. The increased PP2A could be responsible for the dephosphorylation of Bcl-2 and Bad, permitting apoptotic activity of Bax and Bad. The increase of caspase 8 and 9 suggested that both the intrinsic and extrinsic apoptotic pathways were induced. PP2A was probably increased by PPAR,, since putative PPRE sequences were found in genes encoding its subunits. In conclusion, CLA induces apoptosis in human hepatoma SK-HEP-1 cells, by increasing PPAR,, PP2A and pro-apoptotic proteins. © 2007 Wiley-Liss, Inc. [source] Conjugated linoleic acid inhibits peritoneal metastasis in human gastrointestinal cancer cellsINTERNATIONAL JOURNAL OF CANCER, Issue 3 2006Hiroki Kuniyasu Abstract The effect of conjugated linoleic acid (CLA) on peritoneal metastasis was examined by in vitro treatment of cancer cells and mouse peritoneal metastasis models. First, cell growth of MKN28 human gastric cancer cells and Colo320 human colon cancer cells was suppressed by CLA in a dose-dependent manner with an increment in apoptosis. CLA significantly inhibited invasion into type IV collagen-coated membrane of MKN28 and Colo320 cells (p < 0.05). CLA-induced growth inhibition was recovered by the exposure to antisense S-oligodeoxynucleotide for peroxisome proliferator-activated receptor (PPAR)-, in both cell lines. BALB/c nu-nu mice were inoculated with MKN28 and Colo320 cells into their peritoneal cavity, and administrated with CLA intraperitoneally (weekly, 4 times). CLA treatment did not affect food intake or weight gain of mice. CLA treatment significantly decreased metastatic foci of both cells in the peritoneal cavity (p < 0.005). Survival rate in mice inoculated with MKN28 or Colo320 cells was significantly recovered by CLA treatment (p = 0.0025 and 0.0052, respectively). Protein production in MKN28 and Colo320 cells treated with CLA showed a decrease in epidermal growth factor receptor and transforming growth factor-, and an increase in Bax. These findings suggest that CLA inhibits metastasis of human gastric and colon cancer cells. © 2005 Wiley-Liss, Inc. [source] EFFECT OF WATER ACTIVITY ON PHYSICAL PROPERTIES OF CONJUGATED LINOLEIC ACID (CLA) MICROCAPSULESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2010MARIBEL JIMENEZ ABSTRACT The physical properties of spray drying powders must be considered for the design of equipment. Conjugated linoleic acid (CLA) microcapsules were spray dried by using the following as wall materials: whey protein concentrate (WPC), a blend of whey protein concentrate,maltodextrins (WPC-MD) and gum arabic (GA). These were prepared and their physical properties were studied. The bulk density, packed density, particle density, compressibility and color of the microcapsules were evaluated in a range of water activities from 0.108 to 0.898. No significant differences in the physical properties were found when WPC was used as a wall material in the microcapsules stored at the whole range of water activities tested. Maltodextrins conferred changes in some of the physical properties of the microcapsules (WPC-MD) upon storage at high water activities. GA microcapsules showed drastic changes in all physical properties studied at water activities above 0.628. PRACTICAL APPLICATIONS This work shows the best conditions for storing conjugated linoleic acid (CLA) microcapsules elaborated with different wall materials, which have been reported to have a high potential as a food additive because of the nutraceutical properties of CLA. This research should reveal the behavior of water activity during storage on physical properties, and make it possible to predict what characteristics need to be added to a food, besides being important for the design of equipment, packing and transport. [source] Production of Conjugated Linoleic Acid-Rich Potato ChipsJOURNAL OF FOOD SCIENCE, Issue 1 2007Vishal P. Jain ABSTRACT:, Conjugated linoleic acid (CLA) is found primarily in diary and beef products, but the health benefits of CLA can only be realized if they are consumed at much greater levels than a normal healthy dietary intake. We have recently shown that a CLA-rich soy oil can be produced by simple isomerization of linoleic acid in soy oil by photoirradiation. This oil may allow greatly increased dietary CLA without significantly elevating fat intake. The objective of this study was to prepare CLA-rich potato chips by frying in CLA-rich soy oil. Soy oil was photoisomerized in the presence of iodine catalyst with UV/visible light. The irradiated oil was clay processed to remove the residual iodine and this oil was then used to fry potato chips. Oil was extracted from fried chips and analyzed for its CLA content with gas chromatography. A 1-oz serving of CLA-rich potato chips contained approximately 2.4 g CLA as compared to 0.1 g CLA in 3-oz serving of steak fillet and 0.06 g CLA in 8-oz serving of whole milk. The peroxide value of the oil extracted from potato chips was found to be 1 meq/1000 g sample, which was within the acceptable commercial standards. This study may lead to the commercialization of CLA-rich food products. [source] Conjugated linoleic acid evokes de-lipidation through the regulation of genes controlling lipid metabolism in adipose and liver tissueOBESITY REVIEWS, Issue 3 2005R. L. House Summary Conjugated linoleic acid (CLA) is a unique lipid that elicits dramatic reductions in adiposity in several animal models when included at ,,1% of the diet. Despite a flurry of investigations, the precise mechanisms by which conjugated linoleic acid elicits its dramatic effects in adipose tissue and liver are still largely unknown. In vivo and in vitro analyses of physiological modifications imparted by conjugated linoleic acid on protein and gene expression suggest that conjugated linoleic acid exerts its de-lipidating effects by modulating energy expenditure, apoptosis, fatty acid oxidation, lipolysis, stromal vascular cell differentiation and lipogenesis. The purpose of this review shall be to examine the recent advances and insights into conjugated linoleic acid's effects on obesity and lipid metabolism, specifically focused on changes in gene expression and physiology of liver and adipose tissue. [source] Effects of tocopherols and tocotrienols on the inhibition of autoxidation of conjugated linoleic acidEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2010Soon-Nam Ko Abstract The effect of eight vitamin E homologues, i.e. ,-, ,-, ,-, and ,-tocopherol and ,-, ,-, ,, and ,-tocotrienol, on the inhibition of autoxidation of conjugated linoleic acid (CLA) were investigated. The oxidation was carried out in the dark for 21 days at 50,°C and monitored by peroxide values (PV) and TBA values. The levels of the individual vitamin E homologues in CLA during storage were determined by HPLC. ,-Tocopherol exhibited the highest antioxidant activity among the homologues tested in this study when the antioxidant activities of the individual homologues in CLA were compared by PV. The order of antioxidant activity of eight homologues was ,-tocopherol,>,,-tocopherol,=,,-tocotrienol , ,-tocotrienol,>,,-tocopherol,=,,-tocotrienol,>,,-tocopherol,=,,-tocotrienol. The degradation rates of , -tocopherol and , -tocotrienol were faster than those of the other homologues, whereas ,-tocopherol had the highest stability in CLA during storage. All homologues exhibited an antioxidant activity by inhibiting the formation of secondary oxidation products. It appears that ,-tocotrienol and ,-tocotrienol have significantly higher antioxidant activities for secondary oxidation in CLA than ,-tocopherol and ,-tocopherol. Meanwhile, the other homologues, namely ,-tocopherol, ,-tocotrienol, ,-tocopherol, and ,-tocotrienol, exhibited similar antioxidant activity for secondary oxidation in CLA. [source] Role of biohydrogenation intermediates in milk fat depressionEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 8 2007Kevin J. Shingfield Abstract Fat is the most variable constituent in milk and is reduced on low-fiber/high-concentrate diets or on rations containing lipid supplements rich in polyunsaturated fatty acids. The biohydrogenation theory attributes the causal mechanism underlying diet-induced milk fat depression (MFD) to changes in ruminal lipid metabolism leading to increased formation of specific biohydrogenation intermediates that exert anti-lipogenic effects. Trans -10, cis -12 conjugated linoleic acid (CLA) is the only intermediate shown unequivocally to inhibit milk fat synthesis. However, increases in ruminal trans -10, cis -12 CLA formation do not provide a universal explanation for the reductions in milk fat during diet-induced MFD, suggesting that other biohydrogenation intermediates may also be involved. Post-ruminal infusion experiments have provided tentative evidence that cis -10, trans -12 CLA and trans -9, cis -11 CLA also exert anti-lipogenic effects. Diet-induced MFD is consistently associated with an increase in milk fat trans -10 18:1 concentrations, but recent direct evidence offers little support for a role of this intermediate in the regulation of milk fat synthesis. Further research is required to characterize the structure and function of other biohydrogenation intermediates, as well as considering the contribution of more global changes in ruminal lipid metabolism to provide a more universal explanation of diet-induced MFD. [source] PPAR, and PP2A are involved in the proapoptotic effect of conjugated linoleic acid on human hepatoma cell line SK-HEP-1INTERNATIONAL JOURNAL OF CANCER, Issue 11 2007Giuliana Muzio Abstract Conjugated linoleic acid (CLA), found in dairy products, in beef and lamb has been demonstrated to possess anticancer properties protecting several tissues from developing cancer. Moreover, it has been shown to modulate apoptosis in several cancer cell lines. The aim of this study was to investigate which signaling transduction pathways were modulated in CLA-induced apoptosis in human hepatoma SK-HEP-1 cells. The cells exposed to CLA were evaluated for PPAR,, PP2A, pro-apoptotic proteins Bak, Bad and caspases, and anti-apoptotic proteins Bcl-2 and Bcl-XL. Cells were also treated with okadaic acid, a PP2A inhibitor, or with Wy-14643, a specific PPAR, agonist. The CLA-induced apoptosis was concomitant to the increase of percentage of cells in the S phase, PPAR,, PP2A and pro-apoptotic proteins; simultaneously, antiapoptotic proteins decreased. Inhibition of PP2A prevented apoptosis, and PPAR, agonist showed similar effect as CLA. The increased PP2A could be responsible for the dephosphorylation of Bcl-2 and Bad, permitting apoptotic activity of Bax and Bad. The increase of caspase 8 and 9 suggested that both the intrinsic and extrinsic apoptotic pathways were induced. PP2A was probably increased by PPAR,, since putative PPRE sequences were found in genes encoding its subunits. In conclusion, CLA induces apoptosis in human hepatoma SK-HEP-1 cells, by increasing PPAR,, PP2A and pro-apoptotic proteins. © 2007 Wiley-Liss, Inc. [source] Conjugated linoleic acid inhibits peritoneal metastasis in human gastrointestinal cancer cellsINTERNATIONAL JOURNAL OF CANCER, Issue 3 2006Hiroki Kuniyasu Abstract The effect of conjugated linoleic acid (CLA) on peritoneal metastasis was examined by in vitro treatment of cancer cells and mouse peritoneal metastasis models. First, cell growth of MKN28 human gastric cancer cells and Colo320 human colon cancer cells was suppressed by CLA in a dose-dependent manner with an increment in apoptosis. CLA significantly inhibited invasion into type IV collagen-coated membrane of MKN28 and Colo320 cells (p < 0.05). CLA-induced growth inhibition was recovered by the exposure to antisense S-oligodeoxynucleotide for peroxisome proliferator-activated receptor (PPAR)-, in both cell lines. BALB/c nu-nu mice were inoculated with MKN28 and Colo320 cells into their peritoneal cavity, and administrated with CLA intraperitoneally (weekly, 4 times). CLA treatment did not affect food intake or weight gain of mice. CLA treatment significantly decreased metastatic foci of both cells in the peritoneal cavity (p < 0.005). Survival rate in mice inoculated with MKN28 or Colo320 cells was significantly recovered by CLA treatment (p = 0.0025 and 0.0052, respectively). Protein production in MKN28 and Colo320 cells treated with CLA showed a decrease in epidermal growth factor receptor and transforming growth factor-, and an increase in Bax. These findings suggest that CLA inhibits metastasis of human gastric and colon cancer cells. © 2005 Wiley-Liss, Inc. [source] Enhancement of the conjugated linoleic acid and vitamin A and E contents in goat milk through green fodder feedingINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 1 2009AMRISH TYAGI Twelve lactating crossbred goats (Sanan × Beetal) in early lactation were divided into two groups of six each. Group I was fed on fresh berseem fodder (Trifolium alexandrinum), whereas group II was fed on berseem fodder and concentrate mixture in 1 : 1 ratio to fulfil their nutritional requirements as per National Research Council (1981). Feed intake and milk yield were recorded daily, and milk samples were collected on 0, 30, 45 and 60 days of experimental feeding for the estimation of fat, vaccenic acid, conjugated linoleic acid (CLA), vitamins A and E, and total antioxidant activity. There was no effect (P > 0.05) of dietary treatments on daily as well as total milk yield and milk fat, solids-not-fat and total solids, although average total CLA (mg/g fat) content in milk during the trial was higher(P < 0.01) in group I (18.92) in comparison to group II (10.94). Vitamin A content averaged 0.46 and 0.27 µg/mL and vitamin E, 1.20 and 1.38 µg/mL in milk of groups I and II, respectively, were higher in the berseem-fed group (P < 0.01) and total antioxidant activity of milk was also higher (P < 0.01) in group I than in group II. [source] Stearoyl CoA desaturase (SCD) gene polymorphisms in Italian cattle breedsJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 1 2008E. Milanesi Summary Stearoyl CoA desaturase (SCD) is the key enzyme involved in the endogenous synthesis of conjugated linoleic acid (CLA) in ruminants. Changes in the enzymatic activity as a result of SCD gene polymorphism and regulation have been hypothesized to cause diet-independent variations of CLA content in milk. Evidences for the direct influence of SCD polymorphism on fatty acid composition of milk and beef have also been reported. To evaluate genetic differences because of breed and/or selection goal, we investigated the polymorphism of three previously reported single nucleotide polymorphisms located in exon 5 of the SCD gene in 11 cattle breeds raised in Italy and selected for different production goals. Results obtained: (i) evidenced a high variability in the allele frequencies across breeds; (ii) detected three novel haplotypes, one of which is private to indigenous beef breeds, and (iii) showed a significant association between haplotypes and selective goal. [source] Production of conjugated linoleic acid by probiotic Lactobacillus acidophilus La-5JOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2009M. Macouzet Abstract Aims:, To study the ability of the probiotic culture Lactobacillus acidophilus La-5 to produce conjugated linoleic acid (CLA), which is a potent anti-carcinogenic agent. Methods and Results:, The conversion of linoleic acid to CLA was studied both by fermentation in a synthetic medium and by incubation of washed cells. Accumulation of CLA was monitored by gas chromatography analysis of the biomass and supernatants. While the fermentation conditions applied may not be optimal to observe CLA production in growing La-5 cells, the total CLA surpassed 50% of the original content in the washed cells after 48 h under both aerobic and micro-aerobic conditions. The restriction of oxygen did not increase the yield, but favoured the formation of trans, trans isomers. Conclusions:, The capability of L. acidophilus La-5 to produce CLA is not dependant on the presence of milk fat or anaerobic conditions. Regulation of CLA production in this strain needs to be further investigated to exploit the CLA potential in fermented foods. Significance and Impact of the study:, Knowledge gained through the conditions on the accumulation of CLA would provide further insight into the fermentation of probiotic dairy products. The capacity of the nongrowing cells to produce CLA is also of great relevance for the emerging nonfermented probiotic foods. [source] Kinetics of microbial hydrogenation of free linoleic acid to conjugated linoleic acidsJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2008H. Xu Abstract Aims:, To investigate the ability of selected probiotic bacterial strains to produce conjugated linoleic acid (CLA) and also to estimate the biohydrogenation kinetics of Lactobacillus acidophilus on the production of CLA from free linoleic acid (LA). Methods and Results:, Six probiotic bacteria, Lact. paracasei, Lact. rhamnosus GG, Lact. acidophilus ADH, and Bifidobacterium longum B6, Lact. brevis, and Lact. casei, were used to examine their ability to convert LA to CLA. LA tolerance was evaluated by addition of different LA concentrations in MRS broth. Lact. acidophilus showed the major tolerant to LA and the greatest CLA-producing ability (36,48 ,g ml,1 of CLA). The rate-controlling steps were k2 and k1 for the addition of 1 and 3 mg ml,1 of LA, respectively. The percentage of CLA conversion was higher in MRS broth supplemented with 1 mg ml,1 (65%) than 3 mg ml,1 (26%). Conclusion:, The results provide useful information and new approach for understanding the biohydrogenation mechanisms of CLA production. Significance and Impact of the Study:, This study would help elucidate the pathway from LA to stearic acid (SA), known as biohydrogenation. In addition, the use of selected probiotic bacteria might lead to a significant improvement in food safety. [source] CHARACTERIZING QUALITY OF RENDERED DUCK FAT COMPARED TO OTHER FATS AND OILSJOURNAL OF FOOD QUALITY, Issue 2 2007YUANSHENG GONG ABSTRACT The characteristics of rendered duck fat (RDF) were compared to commercial sources of soybean oil, lard, tallow, butter and olive oil. RDF was highly susceptible to lipid oxidation during storage compared to the other fats and oils. However, 0.005% tert-butyl hydroquinone delayed the onset of lipid oxidation to an extent that was comparable to the lag phase observed in the commercial fats and oils. Positive attributes of RDF included a relatively high oleic acid content and low saturated fat content. Undesirable attributes of RDF included a lack of conjugated linoleic acid (CLA) and intermediate levels of trans fatty acids (TFA) compared to the other lipid sources. Decreasing the time and temperature of rendering decreased the TFA content in RDF. Around one-half of the TFA content in RDF was vaccenic acid which is converted to CLA after ingestion. [source] Design of Nano-Laminated Coatings to Control Bioavailability of Lipophilic Food ComponentsJOURNAL OF FOOD SCIENCE, Issue 1 2010David Julian McClements ABSTRACT:, There is currently a lack of effective delivery systems to encapsulate, protect, and release bioactive lipophilic components, such as ,-3 fatty acids, conjugated linoleic acid, tributyrin, vitamins, antioxidants, carotenoids, and phytosterols, which is holding back the development of functional foods designed to combat diseases such as coronary heart disease, diabetes, hypertension, and cancer. Delivery systems consisting of lipid droplets encapsulated by nano-laminated biopolymer coatings have great potential for use in the food industry for the encapsulation, protection, and release of bioactive lipids. This article reviews the potential impact of the physicochemical characteristics of nano-laminated biopolymer coatings on the bioavailability of encapsulated lipids. The effects of layer thickness, composition, electrical charge, permeability, and environmental responsiveness on digestion, release, and absorption of lipophilic components are highlighted. The possibility of designing nano-laminated biopolymer coatings to increase, decrease, or control the bioavailability of encapsulated lipids is shown. Data generated from,in vitro,digestion models and animal feeding studies are presented. This knowledge could be used by the food industry to produce functional foods designed to improve human health and wellness. [source] Synthesis of Diacylglycerols Containing CLA by Lipase-Catalyzed EsterificationJOURNAL OF FOOD SCIENCE, Issue 7 2006In-Hwan Kim ABSTRACT:, Diacylglycerols (DAG) were prepared by esterification of glycerol with conjugated linoleic acid (CLA) in the presence of an immobilized 1,3-regiospecific lipase from Rhizomucor miehei and vacuum conditions. The effects of several parameters, namely, temperature, enzyme loading, stirring speed, and vacuum, on the concentration and the purity of the DAG were studied. The reaction temperature influenced both the reaction rate and the concentration of the DAG. The rate of DAG synthesis increased as the enzyme loading increased. However, for high enzyme loadings, the concentration of triacylglycerols (TAG) increased significantly at long reaction times and, as a result, the purity of the DAG decreased. When the stirring speed increased from 150 to 450 rpm, the DAG concentration increased significantly. However, at stirring speeds above 450 rpm, no significant increases in DAG concentration were observed. When the pressure was decreased from 20 to 3 mmHg, the maximum concentration of DAG increased from 76.0% to 80.5%. No increase in the DAG concentration was observed when the pressure was decreased from 3 to 1 mm Hg, even though a slightly higher DAG purity was achieved at 1 mm Hg. For the range of absolute pressures tested, the concentrations of 1,2-DAG were less than 1%. [source] Lipase-mediated Acidolysis of Fully Hydrogenated Soybean Oil with Conjugated Linoleic AcidJOURNAL OF FOOD SCIENCE, Issue 1 2004J. Ortega ABSTRACT: Interesterification (acidolysis) of fully hydrogenated soybean oil (melting point = 69.9 °C) with conjugated linoleic acid (CLA) was carried out in a batch reactor at 75 °C. Lipases from Candida antarctica, Rhizomucor miehei, Pseudomonas sp., and Thermomyces lanuginosus were used at 5% (wt/wt) of the total substrate load. The lipase from Rhizomucor miehei produced the fastest reaction rates, and the greatest extent of incorporation of CLA residues in acylglycerols was achieved in 12 h. Lipases from C. antarctica and T. lanuginosus produced slower initial rates, and maximum extents of incorporation of CLA residues were achieved in 24 h. The lipase from Pseudomonas sp. produced the slowest initial rate. The corresponding maximum extent of incorporation was reached in 48 h. Differential scanning calorimetry analysis of the triacylglycerol (TAG) fractions produced by C. antarctica, R. miehei, and T. lanuginosus lipases after purification by solid phase extraction showed little variation in melting point (60.4 °C, 62.8 °C, and 60.1 °C, respectively). By contrast, the corresponding TAG fraction produced by the Pseudomonas sp. lipase melted at 48.4 °C. The positional distribution of the TAGs produced by the lipase from Pseudomonas sp. differed appreciably from those produced by the other enzymes. [source] Increase of Conjugated Linoleic Acid Content in Milk by Fermentation with Lactic Acid BacteriaJOURNAL OF FOOD SCIENCE, Issue 5 2002Y.J. Kim ABSTRACT: The objectives of this study were to identify the factors and procedures responsible for increasing the conjugated linoleic acid (CLA) content in fermented milk. Fourteen lactic acid bacteria were screened for CLA-producing ability using sunflower oil (containing 70% linoleic acid) as a substrate. Among the screened strains, Lactococcus lactis I-01 showed the highest CLA-producing ability. The optimal concentration of sunflower oil for CLA production was 0.1 g/L in whole milk, which accounted for 0.25% of total milk fat. Our results demonstrated that CLA formation in fermented milk could be affected by numerous factors such as bacterial strain, cell number, optimal substrate concentration, and the period of incubation at neutral pH. [source] Effect of inoculated corn silage enriched with sunflower oil on rumen fermentation and lipid metabolism in an artificial rumen (RUSITEC)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2010an Jal Abstract BACKGROUND: Some rumen isolates are able to produce conjugated linoleic acid (CLA) from linoleic acid (LA) in vitro. Effects of providing diets containing corn silage (CS) and lucerne hay to an artificial rumen (RUSITEC) in which the corn was not inoculated (CS), or inoculated with Lactobacillus plantarum CCM 4000 (CS + LP), Lactobacillus fermentum LF2 (CS + LF) or Enterococcus faecium CCM 4231 (CS + EF) and supplied with sunflower oil (SO; 30 g kg,1; w/w) on rumen metabolism were examined. RESULTS: The SO affected the outputs of all fatty acids. TVA output of uninoculated CS with SO was lower as compared to inoculated CS. The interaction of the CS × SO in the daily output of TVA was detected (P < 0.001). The biohydrogenation of oleic, linoleic, ,-linolenic and total fatty acids was influenced by SO (P < 0.05 and P < 0.001). CONCLUSION: Inoculated silage induces changes in the rumen metabolism which might be related to differences observed in the extent of rumen BH of PUFA in RUSITEC. SO supplementation might positively enhances the production of some rumen intermediates; however, relationships between inoculated silages and oil supplementation can be presumed in the daily production of trans -vaccenic acid. Copyright © 2009 Society of Chemical Industry [source] Conjugated linoleic acid conversion by dairy bacteria cultured in MRS broth and buffalo milkLETTERS IN APPLIED MICROBIOLOGY, Issue 5 2007C.P. Van Nieuwenhove Abstract Aims:, To evaluate strains of Lactobacilli, Bifidobacteria and Streptococci for their ability to produce conjugated linoleic acid (CLA) from free linoleic acid (LA). Methods and Results:, Eight dairy bacteria tolerant to LA were grown in MRS broth containing LA (200 ,g ml,1) and CLA was assessed. Seven bacteria were able to form CLA after 24 h of incubation, varying percentage conversion between 17% and 36%. Lactobacillus casei, Lactobacillus rhamnosus, Bifidobacterium bifidum and Streptococcus thermophilus showed the highest LA conversion and were inoculated into buffalo milk supplemented with different concentration of LA. The production of CLA at 200 ,g ml,1 of LA was two- or threefold in milk than MRS broth. All evaluated strains were able to produce CLA from high LA levels (1000 ,g ml,1). Conclusions:, The most tolerant strain to LA was Lact. casei. Lacttobacillus rhamnosus produced the maximum level of CLA at high LA concentrations (800 ,g ml,1). The selected bacteria may be considered as adjunct cultures to be included on dairy fermented products manufacture. Low concentration of LA must be added to the medium to enhance CLA formation. Significance and Impact of the Study:, The production of CLA by strains using milks from regional farms as medium offer a possible mechanism to enhance this beneficial compound in dairy products and those the possibility to develop functional foods. [source] Cover Picture , Mol.MOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 6 2008Nutr. Regular issues provide a wide range of research and review articles covering all aspects of Molecular Nutrition & Food Research. Selected topics of issue 6 are: Anti-obesity effects of conjugated linoleic acid, docosahexaenoic acid, and eicosapentaenoic acid. Lycopene inhibits growth of human colon cancer cells Resveratrol inhibits migration and invasion of human breast-cancer cells Quantification of the thaumatin-like kiwi allergen by a monoclonal antibody-based ELISA Short-term effects of a low glycemic load diet on hormonal markers of acne [source] Effect of conjugated linoleic acid grafting on the hemocompatibility of polyacrylonitrile membranePOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 6 2006Fu-Chen Kung Abstract Polyacrylonitrile (PAN) membrane was hydrolyzed with NaOH(aq) and grafted with conjugated linoleic acid (CLA) via esterification with 1,3-propanediol. The resulting CLA grafted PAN membranes were characterized using Fourier transform infrared spectrometry (FT-IR) and X-ray photoelectronic spectroscopy (XPS). The effects of CLA grafting on the blood coagulation, platelet aggregation, and oxidative stress were evaluated using human blood. The complete blood count (CBC) and coagulation time (CT) was evaluated in vitro for hemocompatibility. After CLA grafting, the proliferation of human umbilical vein endothelial cells (HUVECs) on the membranes were improved. In addition, the production of reactive oxygen species (ROS) was measured by the chemiluminescence (CL) method to evaluate the oxidative stress. The results showed that the CLA-grafted PAN membrane could keep the CBC values more stable than unmodified PAN membrane. The CLA-grafted PAN membranes also showed longer CT. CLA-grafted PAN membrane could keep the CL counts of hydrogen peroxide and superoxide values more stable than unmodified PAN membrane. These results suggest that a CLA-grafted PAN membrane could offer protection for patients against oxidative stress and would be helpful for reducing the dosage of anticoagulant during hemodialysis. Copyright © 2006 John Wiley & Sons, Ltd. [source] Effects of dietary corn oil and vitamin E supplementation on fatty acid profiles and expression of acetyl CoA carboxylase and stearoyl-CoA desaturase gene in Hu sheepANIMAL SCIENCE JOURNAL, Issue 2 2010Xue-jun CHEN ABSTRACT This study was conducted to assess the effects of dietary corn oil and vitamin E supplementation on fatty acid (FA) profiles and abundances of acetyl-CoA carboxylase (ACC) and ,9 stearoyl-CoA desaturase (SCD) mRNA of Hu sheep. Animals were allocated to three dietary treatments: basal and supplemented with 3% corn oil (CNO), or CNO plus 500 mg/kg vitamin E (COE). The experiment lasted for 10 weeks. No differences were observed in growth performance and carcass qualities among the three treatments (P > 0.05). Feeding CNO and COE diets increased polyunsaturated FAs including cis 9 trans 11 conjugated linoleic acid, and decreased saturated FA in longissimus muscle (P < 0.05). The mRNA abundances of ACC and SCD as detected by real-time PCR were reduced (P < 0.05) in liver and subcutaneous fat by supplementary oil, while the SCD mRNA level in longissimus muscle was also reduced (P < 0.05). Inclusion of vitamin E did not have further effects on mRNA abundances of these two enzymes. It is suggested that dietary corn oil supplementation may reduce FA biosynthesis and influence FA profiles in Hu sheep through decreased expression of both ACC and SCD genes. [source] Effects of dietary supplementation with conjugated linoleic acid on fatty acid composition and lipid oxidation in chicken breast meatANIMAL SCIENCE JOURNAL, Issue 4 2009Satoshi KAWAHARA ABSTRACT We investigated the effects of dietary conjugated linoleic acid (CLA) on fatty acid composition and lipid oxidation in breast meat of broiler chickens. Broiler chickens (28-day-old females) were fed diets containing experimental oils at 20 g/kg diet for 28 days. The experimental oils consisted of either a 2:0, 1:1, or a 0:2 (wt : wt) ratio of safflower oil (high linoleic acid content) to a commercial CLA mixture. In this study, dietary CLA supplementation significantly increased the composition and content of CLA in chicken meat. The predominant CLA in meat from birds with supplemented diets was the cis -9, trans -11 isomer. The proportion of saturated fatty acid in meat significantly increased with increasing CLA supplementation, with a corresponding decrease in monounsaturated fatty acid. Dietary CLA also reduced thiobarbituric acid reactive substances (TBARS) values in raw meat during storage at 4°C for 5 days. These results provide evidence that CLA feeding is a practical strategy not only for adding nutritional benefits to chicken meat but also for improving meat quality including oxidative stability. [source] Control of adipogenesis in ruminantsANIMAL SCIENCE JOURNAL, Issue 5 2006Sang-Gun ROH ABSTRACT Adipose tissue is an important organ that is involved in the peripheral regulation of body homeostasis, specifically, energy intake, storage and expenditure. Since fat metabolism is of the utmost importance in ruminants, the signals and mechanisms which regulate adiposity for fattening have been studied and characterized by many different approaches. Adipogenesis in the adipose tissues of ruminants is triggered and modulated by several factors/genes, some of which (conjugated linoleic acid, tumor necrosis factor-, and adipogenin) have been examined with respect to adipogenesis in ruminants by numerous researchers, including those in our group. The purpose of this article was to describe recent advances and insights into the molecular regulating processes of preadipocyte, adipocyte and adipose tissues in ruminants. [source] Fucoxanthin-rich seaweed extract suppresses body weight gain and improves lipid metabolism in high-fat-fed C57BL/6J miceBIOTECHNOLOGY JOURNAL, Issue 9 2010Seon-Min Jeon Abstract An ethanol extract of fucoxanthin-rich seaweed was examined for its effectiveness as a nutraceutical for body fat-lowering agent and for an antiobese effect based on mode of actions in C57BL/6J mice. Animals were randomized to receive a semi-purified high-fat diet (20% dietary fat, 10% corn oil and 10% lard) supplemented with 0.2% conjugated linoleic acid (CLA) as the positive control, 1.43% or 5.72% fucoxanthin-rich seaweed ethanol extract (Fx-SEE), equivalent to 0.05% or 0.2% dietary fucoxanthin for six weeks. Results showed that supplementation with both doses of Fx-SEE significantly reduced body and abdominal white adipose tissue (WAT) weights, plasma and hepatic triglyceride (TG), and/or cholesterol concentrations compared to the high-fat control group. Activities of adipocytic fatty acid (FA) synthesis, hepatic FA and TG synthesis, and cholesterol,regulating enzyme were also lowered by Fx-SEE supplement. Concentrations of plasma high-density lipoprotein-cholesterol, fecal TG and cholesterol, as well as FA oxidation enzyme activity and UCP1 mRNA expression in epididymal WAT were significantly higher in the Fx-SEE groups than in the high-fat control group. CLA treatment reduced the body weight gain and plasma TG concentration. Overall, these results indicate that Fx-SEE affects the plasma and hepatic lipid profile, fecal lipids and body fat mass, and alters hepatic cholesterol metabolism, FA synthesis and lipid absorption. [source] Bioconversion of Linoleic Acid into Conjugated Linoleic Acid by Immobilized Lactobacillus reuteriBIOTECHNOLOGY PROGRESS, Issue 3 2003Sun-Ok Lee Lactobacillus reuteri was immobilized on silica gel to evaluate the bioconversion of linoleic acid (LA) into conjugated linoleic acid (CLA), consisting of cis -9,trans -11 and trans -10,cis -12 isomers. The amount of cell to carrier, the reaction time, and the substrate concentration, pH, and temperature for CLA production were optimized at 10 mg of cells/(g of carrier), 1 h, 500 mg/L LA, 10.5, and 55 °C, respectively. In the presence of 1.0 mM Cu2+, CLA production increased by 110%. Under the optimal conditions, the immobilized cells produced 175 mg/L CLA from 500 mg/L LA for 1 h with a productivity of 175 mg/(L·h) and accumulated 5.5 times more CLA than that obtained from bioconversion by free washed cells. The CLA-producing ability of reused cells was investigated over five reuse reactions and was maximal at pH 7.5, 25 °C, and 1.0 mM Cu2+. The total amount of CLA by the combined five reuse reactions was 344 mg of CLA/L reaction volume. This was 8.6 times higher than the amount obtained from reuse reactions by free washed cells. [source] | |||||||||||||||||||||||||||||||