C9t11 Conjugated Linoleic Acid Research Articles

Small molecule linoleic acid inhibiting whey syneresis via interact with milk proteins in the fermentation of set yogurt fortified with c9,t11-conjugated linoleic acid.

The study aimed to investigate the impact of fermentation conditions on c9,t11-conjugated linoleic acid (CLA) synthesis by Lactobacillus casei, as well as its effects on whey syneresis, water holding capacity (WHC), and texture characteristics of set yogurt. The amount of whey syneresis decreased about 30% with the adding of 0.1% linoleic acid (LA). The interaction between LA and casein (CS), β-lactoglobulin (β-Lg) and bovine serum albumin (BSA) was observed by UV-Vis absorption spectroscopy, 3D fluorescence spectroscopy and CD spectroscopy. It found that LA changed the microenvironment and polarity around amino acids, as well as the conformation of the three milk proteins. Scanning electron microscope (SEM) analysis revealed that the addition of LA resulted in a more uniform and compact microstructure of the set yogurt. It indicates that LA can promote the crosslink of milk proteins, which may be the reason for the reduction of whey syneresis in set yogurt.

Biosynthesis of c9,t11-conjugated linoleic acid and the effect on characteristics in fermented soy milk

The objective of this work was to investigate the effect of fermentation conditions on c9,t11-conjugated linoleic acid (CLA) synthesized by Lactobacillus casei and the variation of physicochemical characteristics, including pH, viable cell number, syneresis and texture profile, of fermented soy milk (FSM) during storage at 4 °C for 28 days. Fermentation in 7°Brix of soy milk (SM) supplemented with 0.1% linoleic acid and incubated at 37 °C for 72 h was found to be the optimal conditions for c9,t11-CLA biosynthesis. Within the storage of 14 days, viable cell number, total flavonoid content, water-holding capacity, spontaneous syneresis and texture profile in FSM remained stable. During the storage of 28 days, the viable cell number and c9,t11-CLA level were higher than 6.58 log CFU/mL and 816.33 μg/g, respectively.

The dietary c9,t11-conjugated linoleic acid enriched from butter reduces breast cancer progression in vivo.

The c9,t11-conjugated linoleic acid (CLA), which is the minor polyunsaturated fatty acid (PUFA) naturally present in butter, has gained attention due to its important preventive effect against breast cancer in vitro. In this paper, the enrichment of c9,t11-CLA from butter was optimized and the preventive effect of dietary c9,t11-CLA against breast cancer in vivo was investigated. Results showed that the concentration of c9,t11-CLA increased more than 10 times via a one-step urea complexation. Furthermore, the dietary c9,t11-CLA showed obvious preventive effect against breast cancer in decreasing the tumor weight and volume, and reducing the tumor incidence up to 50%. In addition, the expression of progesterone receptor and Ki-67 decreased significantly with the treatment of c9,t11-CLA. In conclusion, the dietary c9,t11-CLA enriched from butter showed a preventive effect against breast cancer in vivo via the inhibition of the hormonal receptor and cell proliferation. PRACTICAL APPLICATIONS: This paper provided new insight into the preparation of specific c9,t11-CLA isomer. It can be enriched from butter in large-scale with low-cost by urea complexation. Meanwhile, the enriched dietary c9,t11-CLA can be further processed into cancer prevention functional foods.

CYP4F13 is the Major Enzyme for Conversion of alpha-Eleostearic Acid into <i>cis</i>-9, <i>trans</i>-11-Conjugated Linoleic Acid in Mouse Hepatic Microsomes

Our previous studies have shown that α-eleostearic acid (α-ESA; cis-9, trans-11, trans-13 (c9,t11,t13)-conjugated linolenic acid (CLnA)) is converted into c9,t11-conjugated linoleic acid (CLA) in rats. Furthermore, we have demonstrated that the conversion of α-ESA into CLA is a nicotinamide adenine dinucleotide phosphate (NADPH)-dependent enzymatic reaction, which occurs mostly in the rat liver. However, the precise metabolic pathway and enzyme involved have not been identified yet. Therefore, in this study we aimed to determine the role of cytochrome P450 (CYP) in the conversion of α-ESA into c9,t11-CLA using an in vitro reconstitution system containing mouse hepatic microsomes, NADPH, and α-ESA. The CYP4 inhibitors, 17-ODYA and HET0016, performed the highest level of inhibition of CLA formation. Furthermore, the redox partner cytochrome P450 reductase (CPR) inhibitor, 2-chloroethyl ethyl sulfide (CEES), also demonstrated a high level of inhibition. Thus, these results indicate that the NADPH-dependent CPR/CYP4 system is responsible for CLA formation. In a correlation analysis between the specific activity of CLA formation and Cyp4 family gene expression in tissues, Cyp4a14 and Cyp4f13 demonstrated the best correlations. However, the CYP4F substrate prostaglandin A1 (PGA1) exhibited the strongest inhibitory effect on CLA formation, while the CYP4A and CYP4B1 substrate lauric acid had no inhibitory effect. Therefore, we conclude that the CYP4F13 enzyme is the major enzyme involved in CLA formation. This pathway is a novel pathway for endogenous CLA synthesis, and this study provides insight into the potential application of CLnA in functional foods.

The effect of sunflower seed oil supplementation on the milk fatty acid contents of cows fed leucaena in an intensive silvopastoral system

Transvaccenic acid (TVA), c9t11 conjugated linoleic acid (CLA), and the proportion of unsaturated fatty acids (FAs) in bovine milk are associated with human health benefits. The effect of nutritional supplementation without (NSO) or with sunflower seed oil (63.3% linoleic acid and 28.3% oleic acid) at 20 g/kg (SO20) of dry matter (DM) and 40 g/kg of DM (SO40) was evaluated in milk cows foraging on Leucaena leucocephala in intensive silvopastoral systems (ISS). Two experiments were performed, the first on a specialized tropical dairy farm (STDF) and the second on a dual-purpose tropical farm (DPTF), where cattle are fed an average of 5.8 kg/d and 2.0 kg/d of concentrate, respectively, in addition to grazing on pasture. Sunflower seed oil supplementation tended to decrease forage intake but did not affect milk yield or the milk protein and lactose percentages in either experiment. The proportion of fat, total solids, and milk urea nitrogen (MUN) decreased with oil supplementation on the STDF. However, on the DPTF, these three variables did not change significantly when SO20 or SO40 were compared to NSO, but the values were higher for SO20 compared to SO40. The proportion of CLAc9t11 and TVA linearly increased with the two levels of supplementation in both experiments. Furthermore, the atherogenic FAs decreased, and the milk had greater amounts of unsaturated FAs (UFAs) and a lower atherogenic index. Supplementing cows under an ISS with sunflower seed oil increases the proportion of beneficial milk FAs. On the STDF oil supplementation produced milk with a lower fat content and a greater proportion of high-quality fatty acids, presenting an interesting possibility for fat restricted diets.

Efecto de la especie y la edad de rebrote en el perfil de ácidos grasos de leguminosas y arbustivas tropicales

Se evaluó el efecto de tres edades de rebrote (4, 8 y 12 semanas) sobre la producción de forraje, calidad nutricional y perfil de ácidos grasos en leguminosas herbáceas: Clitoria ternatea, Pueraria phaseoloides, Canavalia brasiliensis, Centrosema molle, Centrosema macrocarpum, Alysicarpus vaginalis y Lablab purpureus; en leguminosas arbustivas: Cratylia argentea, Gliricidia sepium, Desmodium velutinum, Cajanus cajan y Leucaena leucocephala; y en una arbustiva no leguminosa: Moringa oleifera (Moringaceae). Se utilizó un diseño de parcelas divididas con bloques al azar, en el cual la parcela principal fue la especie forrajera y la subparcela la edad de rebrote. Los principales ácidos grasos presentes en las especies fueron el ácido palmítico (C16:0), ácido linolénico (C18:3) y linoleico (C18:2). Sin embargo, en las leguminosas herbáceas y arbustivas, el contenido de ácidos grasos fue diferente y disminuyó con la edad de rebrote en los dos grupos. La relación C18:2/C18:3 fue mayor en las leguminosas herbáceas que en las arbustivas, lo cual podría resultar en una mayor concentración de ácido linoleico conjugado (ALC) en la grasa de la leche. La leguminosa Cajanus cajan presentó el mayor (p<0,05) contenido de ácido linolénico (C18:3) y de precursores de ALC en las tres edades de rebrote evaluadas, lo cual sugiere que su uso en la alimentación de bovinos en sistemas de doble propósito resultaría en concentraciones altas de ALC c9 t11 en la grasa de la leche, en comparación con otras especies.

Bifidobacterium breve with \u03b1-linolenic acid alters the composition, distribution and transcription factor activity associated with metabolism and absorption of fat

This study focused on the mechanisms that fatty acid conjugating strains - Bifidobacterium breve NCIMB 702258 and Bifidobacterium breve DPC 6330 - influence lipid metabolism when ingested with α-linolenic acid (ALA) enriched diet. Four groups of BALB/c mice received ALA enriched diet (3% (w/w)) either alone or in combination with B. breve NCIMB 702258 or B. breve DPC 6330 (109 CFU/day) or unsupplemented control diet for six weeks. The overall n-3 PUFA score was increased in all groups receiving the ALA enriched diet. Hepatic peroxisomal beta oxidation increased following supplementation of the ALA enriched diet with B. breve (P < 0.05) and so the ability of the strains to produce c9t11 conjugated linoleic acid (CLA) was identified in adipose tissue. Furthermore, a strain specific effect of B. breve NCIMB 702258 was found on the endocannabinoid system (ECS). Liver triglycerides (TAG) were reduced following ALA supplementation, compared with unsupplemented controls (P < 0.01) while intervention with B. breve further reduced liver TAG (P < 0.01), compared with the ALA enriched control. These data indicate that the interactions of the gut microbiota with fatty acid metabolism directly affect host health by modulating n-3 PUFA score and the ECS.

Dietary CLA supplementation of pigs confers higher oxidative stability to Ciauscolo and Fabriano salami produced from their meat with no negative impact on the physico‐chemical, microbiological and sensorial characteristics

It has been reported that conjugated linoleic acid (CLA) isomers are considered particularly beneficial to human health and affect the technological properties of pork meat products such as salami. The objective of this study was to evaluate the effect of 0.5% CLA supplementation of heavy pig diets on the chemical composition, total fatty acids (FA), oxidative stability, sensory and microbial properties of Ciauscolo and Fabriano salami. The incorporation of CLA into the diet did not modify the chemical, microbial or sensory descriptive analysis of the salami. The CLA dietary supplementation changed the proportions of FA, in particular leading to an increase in the proportion of saturated fatty acids and CLA in both Ciauscolo and Fabriano salami. The results of consumer testing showed a higher degree of liking by consumers when the CLA sample was accompanied by product information, demonstrating the strong influence of the label on consumer perception. The interesting finding was the increase in the oxidative stability of the salami at the end of ripening. This confirms the hypothesis that CLA can affect the saturated and monounsaturated fatty acids/monounsaturated FA ratio in meat products and possesses antioxidative properties that can be transferred, through dietary supplementation, to salami.Practical applications: Feeding a 0.5% CLA diet to finisher pigs resulted in changes in the proportions of FA and enhanced the oxidative stability of salami but did not modify the sensory properties of the products. More research is needed to find the right inclusion level of CLA to be considered optimal from the point of view of producing a high quality product with superior organoleptical, technological and potential health‐related properties.Production of value‐added meat products, such as conjugated linoleic acids (CLA) enriched Ciauscolo and Fabriano salamis, by the inclusion of the c9 t11 and t10 c12 CLA isomers in the swine diet.

Dietary effect of silage type and combination with camelina seed on milk fatty acid profile and antioxidant capacity of sheep milk

The present study sought to quantify the differences between maize-based (MS) and grass-silage-based (GS) diets in terms of their effect on the milk yield, milk fatty acid composition and antioxidant capacity in dairy ewes, and to test the hypothesis that it is possible to improve yield, fatty acid (FA) composition and antioxidant capacity by supplementing diet with camelina seed (Cs). Experimental diets consisted of a 2 x 2 factorial arrangement of type of silage (GS vs. MS) and camelina seed (−Cs vs. +Cs). Feeding the MS diets increased net energy for lactation (NEL) intake, raw milk yield and fat, protein and lactose yields. Feeding +Cs increased energy corrected milk (ECM), milk fat content and fat yield. Maize silage consumption is associated with an increased proportion of hypercholesterolemic fatty acids (HFA) and a higher value of the atherogenicity index. However, an MS diet led to an increased share of t11-C18:1 and c9,t11-conjugated linoleic acid (CLA) in milk. Milk FA profile in ewes fed GS diet was of higher quality for human beings owing to higher concentrations of α-linolenic acid and a lower content of HFA. Supplementing with camelina seed resulted in a higher concentration of t11-C18:1, c9,t11-CLA and C18:3n-3 in milk fat. The trolox equivalent antioxidant capacity (TEAC) value of milk was higher in milk from MS-fed ewes compared with that of their counterparts fed GS. Dietary supplementation with camelina seed increased the oxidative stability of milk samples. These results suggest that grass-silage-based diet supplemented with camelina seed results in milk of better quality for human consumption.Keywords: Milk quality, oilseed, PUFA profile, oxidative stability of milk, TEAC assay

Milk Yield, Composition, and Fatty Acid Profile in Dairy Cows Fed a High-concentrate Diet Blended with Oil Mixtures Rich in Polyunsaturated Fatty Acids.

To evaluate the effects of feeding linseed oil or/and sunflower oil mixed with fish oil on milk yield, milk composition and fatty acid (FA) profiles of dairy cows fed a high-concentrate diet, 24 crossbred primiparous lactating dairy cows in early lactation were assigned to a completely randomized design experiment. All cows were fed a high-concentrate basal diet and 0.38 kg dry matter (DM) molasses per day. Treatments were composed of a basal diet without oil supplement (Control), or diets of (DM basis) 3% linseed and fish oils (1:1, w/w, LSO-FO), or 3% sunflower and fish oils (1:1, w/w, SFO-FO), or 3% mixture (1:1:1, w/w) of linseed, sunflower, and fish oils (MIX-O). The animals fed SFO-FO had a 13.12% decrease in total dry matter intake compared with the control diet (p<0.05). No significant change was detected for milk yield; however, the animals fed the diet supplemented with SFO-FO showed a depressed milk fat yield and concentration by 35.42% and 27.20%, respectively, compared to those fed the control diet (p<0.05). Milk c9, t11-conjugated linoleic acid (CLA) proportion increased by 198.11% in the LSO-FO group relative to the control group (p<0.01). Milk C18:3n-3 (ALA) proportion was enhanced by 227.27% supplementing with LSO-FO relative to the control group (p<0.01). The proportions of milk docosahexaenoic acid (DHA) were significantly increased (p<0.01) in the cows fed LSO-FO (0.38%) and MIX-O (0.23%) compared to the control group (0.01%). Dietary inclusion of LSO-FO mainly increased milk c9, t11-CLA, ALA, DHA, and n-3 polyunsaturated fatty acids (PUFA), whereas feeding MIX-O improved preformed FA and unsaturated fatty acids (UFA). While the lowest n-6/n-3 ratio was found in the LSO-FO, the decreased atherogenecity index (AI) and thrombogenicity index (TI) seemed to be more extent in the MIX-O. Therefore, to maximize milk c9, t11-CLA, ALA, DHA, and n-3 PUFA and to minimize milk n-6/n-3 ratio, AI and TI, an ideal supplement would appear to be either LSO-FO or MIX-O.

Conjugated fatty acids and methane production by rumen microbes when incubated with linseed oil alone or mixed with fish oil and/or malate.

We hypothesized that manipulating metabolism with fish oil and malate as a hydrogen acceptor would affect the biohydrogenation process of α-linolenic acid by rumen microbes. This study was to examine the effect of fish oil and/or malate on the production of conjugated fatty acids and methane (CH4 ) by rumen microbes when incubated with linseed oil. Linseed oil (LO), LO with fish oil (LO-FO), LO with malate (LO-MA), or LO with fish oil and malate (LO-FO-MA) was added to diluted rumen fluid, respectively. The LO-MA and LO-FO-MA increased pH and propionate concentration compared to the other treatments. LO-MA and LO-FO-MA reduced CH4 production compared to LO. LO-MA and LO-FO-MA increased the contents of c9,t11-conjugated linoleic acid (CLA) and c9,t11,c15-conjugated linolenic acid (CLnA) compared to LO. The content of malate was rapidly reduced while that of lactate was reduced in LO-MA and LO-FO-MA from 3 h incubation time. The fold change of the quantity of methanogen related to total bacteria was decreased at both 3 h and 6 h incubation times in all treatments compared to the control. Overall data indicate that supplementation of combined malate and/or fish oil when incubated with linseed oil, could depress methane generation and increase production of propionate, CLA and CLnA under the conditions of the current in vitro study.

Metabolism of c9,t11-conjugated linoleic acid (CLA) in humans

The c9,t11 isomer of conjugated linoleic acid (CLA) is the most abundant CLA form present in the human diet, and is particularly prevalent in milk and dairy products, and is known to exert several health benefits in experimental animal models. A possible mechanism of action of c9,t11CLA relies on its metabolism via desaturases and elongases and partial beta oxidation in peroxisomes. In this study, we aimed to establish plasma incorporation of c9,t11CLA and its downstream metabolites in healthy volunteers after daily dietary intakes of 0.8g, 1.6g or 3.2g of c9,t11CLA in capsule form for two months. Following supplementation, the plasma concentrations of c9,t11CLA and its metabolites conjugated dienes (CD) 18:3 and the beta oxidation product CD 16:2 were incorporated in a linear fashion, while on the other hand CD 20:3 reached a plateau following intakes of 1.6g/d of dietary intake, and was not further increased following higher CLA intakes. We may conclude that supplementation of c9,t11 CLA levels result in linear responses of CLA and its main metabolites in plasma. In addition, only the highest concentration of CLA intake tested (3.2g/d) yielded plasma concentrations of CLA and metabolites close to the range found sufficient to exert nutritional effects in experimental animal models.

Trans‐10,cis‐12 Conjugated Linoleic Acid Improved Growth Performance, Reduced Lipid Deposition and Influenced CPT I Kinetic Constants of Juvenile Synechogobius hasta

trans-10,cis-12 (t10c12) Conjugated linoleic acid (CLA) reduced body lipid deposition in various experimental animals, but the mechanisms involved were still emerging. Carnitine palmitoyltransferase I (CPT I) catalyzes an important regulatory step in lipid metabolism. At present, no studies, to our knowledge, have evaluated the kinetic constants influenced by dietary CLA in fish. In the present study, we tested the hypothesis that changes in body lipid content in fish as a response to dietary t10c12 CLA was related to the change of CPT I kinetic constants [Michaelis constant (K m), maximal velocity and catalytic efficiency for carnitine and palmitoyl-CoA]. Juvenile Synechogobius hasta were fed three experimental diets with fish oil replaced with 0 (control), 1, or 2% t10c12 CLA for 8weeks. Weight gain, specific growth rate and protein efficiency rate increased with dietary t10c12 CLA level. Dietary t10c12 CLA addition significantly reduced lipid contents both in liver and muscle. Dietary CLA addition also improved CPT I activities in muscle but did not significantly influence hepatic CPT I activity. CPT I kinetic parameters (K m, V max and catalytic efficiency) were significantly influenced by t10c12 CLA. CPT I catalytic efficiencies with carnitine and palmitoyl-CoA as substrates were higher in muscle and liver of fish fed increasing t10c12 CLA. For the first time, the findings demonstrated effect of dietary CLA addition on CPT I kinetics in fish and supported our starting hypothesis that dietary t10c12 CLA addition induced alterations in CPT I kinetic constants of muscle and liver. Increased CPT I catalytic efficiency might be the main reason for reduced lipid deposition in these tissues by dietary t10c12 CLA supplementation.

The Effect of Forage Level and Oil Supplement on Butyrivibrio fibrisolvens and Anaerovibrio lipolytica in Continuous Culture Fermenters.

The objective of this study was to evaluate the effects of forage level and oil supplement on selected strains of rumen bacteria believed to be involved in biohydrogenation (BH). A continuous culture system consisting of four fermenters was used in a 4×4 Latin square design with a factorial arrangement of treatments, with four 10 d consecutive periods. Treatment diets were: i) high forage diet (70:30 forage to concentrate (dry matter basis); HFC), ii) high forage plus oil supplement (HFO), iii) low forage diet (30:70 forage to concentrate; LFC), and iv) low forage plus oil supplement (LFO). The oil supplement was a blend of fish oil and soybean oil added at 1 and 2 g/100 g dry matter, respectively. Treatment diets were fed for 10 days and samples were collected from each fermenter on the last day of each period 3 h post morning feeding. The concentrations of vaccenic acid (t11C18:1; VA) and c9t11 conjugated linoleic acid (CLA) were greater with the high forage diet while the concentrations of t10 C18:1 and t10c12 CLA were greater with the low forage diet and addition of oil supplement increased their concentrations at both forage levels. The DNA abundance of Anaerovibrio lipolytica, and Butyrivibrio fibrisolvens vaccenic acid subgroup (Butyrivibrio VA) were lower with the low forage diets but not affected by oil supplement. The DNA abundance of Butyrivibrio fibrisolvens stearic acid producer subgroup (Butyrivibrio SA) was not affected by forage level or oil supplement. In conclusion, oil supplement had no effects on the tested rumen bacteria and forage level affected Anaerovibrio lipolytica and Butyrivibrio VA.

The effect of level of forage and oil supplement on biohydrogenation intermediates and bacteria in continuous cultures

The objective of this study was to investigate how level of forage and oils in ruminant animals’ diet affect selected strains of ruminal bacteria believed to be involved in biohydrogenation (BH). Four continuous culture fermenters were used in 4×4 Latin square design with a 2×2 factorial arrangement over four consecutive periods of 10 days each. The experimental diets used in this study were: high forage diet (700:300g/kg (DM basis) forage to concentrate; HFC), high forage with oil supplement (HFO), high forage diet (300:700g/kg (DM basis) forage to concentrate; LFC), and high forage with oil supplement (HFO). The oil supplement was a blend of fish oil (FO) and soybean oil (SBO) added at 10 and 20g/kg DM, respectively. Acetate concentration was greater (P<0.01) with the high forage diets whereas propionate concentration was greater (P<0.02) with the low forage diets and both decreased (P<0.05) with oil supplementation. The concentrations of t11 C18:1 (vaccenic acid, VA) and c9t11 conjugated linoleic acid (CLA) were greater (P<0.01) with the high than the low forage diets and concentrations increased (P<0.01) with oil supplementation particularly when added with the high forage diet. The concentrations of t10 C18:1 and t10c12 CLA were greater (P<0.01) with the low than the high forage diets and concentrations increased (P<0.01) with oil supplementation particularly when added with the low forage diet. The DNA abundance of Butyrivibrio fibrisolvens, Ruminococcus albus, Ruminococcus flavefaciens, Anaerovibrio lipolytica and Butyrivibrio proteoclasticum were greater (P<0.03) with the high than the low forage diets. Oil supplementation reduced (P<0.05) the DNA abundance only for R. flavefaciens, B. fibrisolvens and R. albus especially when added with the high forage diet. Results from this study suggest that the greater trans fatty acids (FA) production seen with the high forage diets may be related to greater activity of B. fibrisolvens, R. flavefaciens and R. albus, and B. proteoclasticum appears to play a minor role in the production of C18:0 from trans C18:1.

Inhibitory effect of t10 c12 conjugated linoleic acid (CLA) isomer on clozapine induced adipogenesis in 3T3‐L1 cells

Atypical (second generation) antipsychotics such as clozapine have become the primary choice of medication for treating psychosis. An unfortunate side‐effect of these medications is weight gain, a condition often associated with the development of metabolic disorders such as diabetes. Factors thought to facilitate this weight gain include increased food intake, reduced energy expenditure, and impaired pre‐adipocyte differentiation. CLA, specifically the t10 c12 isomer, has been known to suppress adipogenesis both in vitro and in vivo model. Thus we tested the effect of the t10 c12 CLA on clozapine induced adipogenesis in 3T3‐L1 cells. 3T3‐L1 pre‐adipocytes were differentiated by the addition of insulin (1μg/ml), dexamethasone (1μM), IBMX (10mM), and 10% FBS in DMEM medium. Cells were treated with or without clozapine (10 and 20μM) and/or t10 c12 CLA (50μM). Lipid accumulation was measured by Oil‐red O staining and intracellular triacylglyceride contents were analyzed. mRNA level of the lipid metabolism related transcription factors were measured by RT‐PCR. Cells treated with clozapine alone showed significant increase in lipid accumulation compared to control. However, increased lipid accumulation by clozapine was significantly prevented in cells treated with CLA. mRNA level of fatty acid synthase (FAS), acetyl‐CoA carboxylase (ACC), uncoupling protein‐2 (UCP‐2), and peroxisome proliferator‐activated receptor‐γ (PPAR‐γ) in the cells treated with CLA were significantly decreased by t10 c12 CLA with or without treatment of clozapine. These results suggest that CLA may be used to prevent fat accumulation associated with antipsychotic administration.

Attenuation of 12-O-Tetradecanoylphorbol-13-acetate (TPA)-Induced Gap Junctional Intercellular Communication (GJIC) Inhibition in MCF-10A Cells by c9,t11-Conjugated Linoleic Acid

The protective effect of c9,t11-conjugated linoleic acid (CLA) on the inhibition of gap junctional intercellular communication (GJIC) was examined in a human mammary epithelial cell line (MCF-10A) treated with 12-O-tetradecanoylphorbol-13-acetate (TPA), relative to t10,c12-CLA isomer. TPA inhibited GJIC in a dose-dependent and reversible manner and was associated with connexin 43 phosphorylation. Pretreatment of 20 μM c9,t11-CLA for 24 h prior to 60 nM TPA for 1 h prevented the inhibition of GJIC by reducing the phosphorylation of connexin 43 via suppressing extracellular signal-regulated kinases (ERK1/2) activation. Reactive oxygen species (ROS) accumulation by TPA was attenuated by c9,t11-CLA. The efficacy of c9,t11-CLA in protecting inhibition of GJIC, connexin 43 phosphorylation, and ROS production was superior to that of t10,c12-CLA. These results suggest that c9,t11-CLA, including t10,c12-CLA, prevents the carcinogenesis of MCF-10A cells by protecting down-regulation of GJIC during the cancer promotion stage, and lack of their toxicities could be an excellent indicator for the chemoprevention of breast cancer.

Ruminal biohydrogenation of unsaturated fatty acids in vitro as affected by chitosan

Because of the health-promoting effects of conjugated linoleic acid (CLA) isomers in humans, there is growing interest in increasing the content of C18:1 t11 in the rumen in order to enhance the final CLA level in ruminant milk and meat products. Modifying ruminal microflora populations has been viewed as a means to increase their C18:1 t11 content. Therefore, the objective of this experiment was to identify whether chitosan, a natural antimicrobial agent, could be used to modify the biohydrogenation intermediates of two fat sources. The study used a Rusitec unit consisting of eight vessels, and the diets were grass hay and a concentrate mixture (10:90) formulated using either sunflower or rapeseed meal as a fatty acid (FA) source. The incubation experiment consisted of a 6-day adaptation followed by a 5-day chitosan dosing period (750 mg/d), sampling for FA profile and pH determination on the last 3 days. Chitosan interfered in FA biohydrogenation, decreasing total C18:0 (48.7 g/100 g FA versus 23.2 g/100 g FA; P < 0.01) and increasing total C18:1 (5.4 g/100 g FA versus 25.8 g/100 g FA; P < 0.05), C18:1 t11 (4.5 g/100 g FA versus 19.6 g/100 g FA; P < 0.05), total CLA (0.17 g/100 g FA versus 0.37 g/100 g FA; P < 0.05), t9t11 CLA (0.10 g/100 g FA versus 0.21 g/100 g FA; P < 0.05), and the C18:1 t11/C18:0 ratio (0.09 g/100 g FA versus 0.89 g/100 g FA; P < 0.05). Compared to sunflower meal, when rapeseed meal was incubated as the fat source in the concentrate mixture, only total C16:0 was decreased (22.9 g/100 g FA versus 20.6 g/100 g FA; P < 0.05). Chitosan supplementation increased proportions of C18:1 c9, C18:1 c11, and t10c12 CLA only when rapeseed meal was used as the fat source in the concentrate mixture. Chitosan was very effective at inhibiting biohydrogenation in vitro by increasing C18:1 t11 and total CLA proportions and lowering the proportion of saturated FA, regardless of the FA source. However, chitosan increased other biohydrogenation intermediates to a greater extent with rapeseed meal as the dietary fat source.

Effects of corn-, wheat- or triticale dry distillers’ grains with solubles on in vitro fermentation, growth performance and carcass traits of lambs

The objective of this study was to determine the effect of replacing a mixture of canola meal and barley grain with corn-, wheat- or triticale dry distillers’ grains with solubles (DDGS) at 20% of dietary dry matter (DM) on in vitro ruminal fermentation in bovine ruminal fluid and on growth performance and carcass characteristics of lambs. Sixty ram lambs (22.6 ± 3.0 kg) were randomly assigned to one of four dietary treatments and given individual ad libitum access to feed until they attained slaughter weight. The control diet consisted (DM basis) of 54% barley grain, 16% sunflower hulls, 11.5% beet pulp, 10% canola meal, 2.5% canola oil and 6.0% molasses, vitamins and minerals mixture. For the three DDGS dietary treatments, 10% barley grain and 10% canola meal were replaced with 20% corn-, wheat-or triticale-DDGS. The source of DDGS did not influence (P &gt; 0.51) dry matter intake (DMI) or average daily gain (ADG). Feed conversion (feed:gain) of lambs fed wheat DDGS was approx. 12% poorer (P &lt; 0.05) than that of lambs fed control or corn DDGS diets. In vitro data suggest that the inefficient gain may have been attributable to greater (P &lt; 0.05) ammonia concentration at 24 h and lower digestibility of wheat DDGS. Carcass traits, including hot carcass weight, body wall thickness and saleable meat yield, were not affected (P &gt; 0.60) by dietary treatment. Total saturated, monounsaturated and polyunsaturated fatty acids in subcutaneous fat were also not affected by DGGS source (P ≥ 0.13). There was no treatment effect (P = 0.33) on concentrations of t11-18:1, but feeding triticale DDGS increased the concentration (P = 0.04) of c9, t11-conjugated linoleic acid (CLA). In conclusion, DDGS from corn, wheat or triticale can replace a mixture of barley grain and canola meal at 20% of dietary DM without adversely affecting DMI, ADG or carcass characteristics of growing lambs, although wheat DDGS may reduce feed conversion ratio (feed:gain). Including triticale DDGS may also improve the fatty acid profile of subcutaneous fat.Key words: Lamb, corn, wheat, triticale, distillers’ grains, performance, carcass characteristics

Influence of organic systems on milk fatty acid profile and CLA in goats

The effect of organic system on the fatty acid profile of milk and CLA content was evaluated using 30 pregnant pluriparous goats, divided into two homogeneous groups (S and O) of 15 goats each. Group S was housed in a stable and received alfalfa hay as forage, while group O was raised according EC Regulation 834/2007 and led to pasture. After the kids weaning, goats were milked twice a day for 5 months. Daily milk yield was recorded and, monthly, representative milk samples from the two daily milkings were analysed for chemical and fatty acid profile. Average milk yield did not differ statistically between the groups. The goats of the O group had significantly higher fat content in milk than those of group S (65.9 g/day vs. 54.3 g/day, P < 0.01). Among milk fatty acids, organic system significantly affected the percentages of C18:1 c9, C18:1 t11, linoleic acid, alpha-linolenic acid, monounsaturated fatty acid and polyunsaturated fatty acid. Organic system highly influenced the c9 t11 conjugated linoleic acid (CLA) (0.810 g/100 g of fat vs. 0.542 g/100 g of fat, for groups O and S, respectively, P < 0.01), t10 c12 CLA (0.041 g/100 g of fat vs. 0.024 g/100 g of fat, for groups O and S, respectively, P < 0.01) and ∑CLA (0.87 g/100 g of fat vs. 0.58 g/100 g of fat for groups O and S, respectively, P < 0.01) concentrations of milk.