Improving the production of conjugated linoleic acid from sunflower oil by lactic acid bacteria spp: Effect of calcium carbonate supplementation in fermentation medium

Conjugated linoleic acid (CLA) is a polyunsaturated fatty acid with various positional and geometric isomers of linoleic acid (LA) present mainly in food items and produced endogenously in non-ruminants and humans or through fermentation process. It is associated with health-beneficial effects and subject to more research on its natural sources (ruminant-derived foods) and strategies to increase the content in various foodstuffs. Although several studies have reported the most common intake value of 0.8 g/day (0.6 to 3.0 g/day), research for raising in situ concentration should focus on strategies such as in vitro bioconversion of its precursors by bacteria and supplementation of LA rich-oils in foods fermentation process. In this study, the ability of some lactic acid bacteria (LAB) from diverse samples to produce CLA from sunflower oil and the effect on production yield of fermentation medium supplementation with carbonate calcium were investigated. Results showed that ten Limosilactobacillus fermentum and Enterococcus faecium produced trans-10, cis-12-CLA isomer accounted for at least 85% of total CLA ranging from 4.64 to 5.22 µg/mL. Despite the fermentation medium supplementation with CaCO3 enhanced the production yield, the residual LA inhibitory effect on bacteria growth governing CLA biosynthesis process was not mitigated. So, although our LAB strains can produce CLA, the more the LA concentration goes up, the more the conversion rate downgrades. Further studies on strains behavior in a wide range of LA concentrations will help establish a stable relationship between bacteria and LA in the presence of CaCO3.

Intramuscular fatty acid composition of steers finished on oat pastures mixture with vetch or cornmeal supplementation / Composição de ácidos graxos da gordura intramuscular de novilhos terminados em pastagem de aveia consorciada com ervilhaca ou suplementados com grão de milho moído

ABSTRACT: The effects of energetic supplementation and mixture vetch (Vica sativa L.) were studied to evaluate the intramuscular fatty acid profile of steers finished on oat (Avena sativa L.) pastures. Eighteen 21-month-old crossbred steers were evaluated. The experiment was carried out in three treatments and six repetitions: oat pasture (OA), oat pasture + vetch (OA + VET), and oat pasture + supplementation (OA + SUP). Supplementation comprised the addition of corn meal at a daily dose of 1% of the animals' body weight. Steers receiving supplementation had higher lipid content in Longissimus lumborum than did those fed with OA + VET (1.25 vs 1.02%), whereas those fed with OA (1.15%) showed intermediate values. Conjugated linoleic acid levels were higher in steers fed OA (0.57%) and OA + SUP (0.59%), whereas the highest amount of omega-3 fatty acids was observed in animals fed OA + VET (3.32%). Pasture-finishing without supplementation resulted in a lower ratio of n-6:n-3 (3.14). Steers finished in oat mixture with vetch showed healthier intramuscular fat than did those finished with cornmeal supplementation; importantly, the higher the amount of PUFAs, the better n-6:n-3 ratio.

RESUMO: Os efeitos da suplementação energética e da ervilhaca (Vica sativa L.) foram estudados para avaliar o perfil de ácidos graxos intramusculares de novilhos terminados em pastagens de aveia (Avena sativa L.). Foram avaliados 18 novilhos mestiços com 21 meses de idade. O experimento foi realizado em três tratamentos e seis repetições: pastagem de aveia (OA), pastagem de aveia + ervilhaca (OA + VET) e pastagem de aveia + suplementação (OA + SUP). A suplementação compreendeu a adição de fubá na dose diária de 1% do peso corporal dos animais. Os novilhos que receberam suplementação apresentaram maior teor lipídico no Longissimus lombar do que aqueles alimentados com OA + VET (1,25 contra 1,02%), enquanto aqueles alimentados com AO (1,15%) apresentaram valores intermediários. Os níveis de ácido linoléico conjugado foram maiores em novilhos alimentados com AO (0,57%) e OA + SUP (0,59%), enquanto a maior quantidade de ácidos graxos ômega-3 foi observada em animais alimentados com OA + VET (3,32%). Animais terminados em pastagens sem suplementação apresentaram menor proporção de n-6: n-3 (3,14). Novilhos terminados em pastagem de aveia com ervilhaca apresentaram gordura intramuscular mais saudável do que aqueles terminados com suplementação de milho moído, uma vez que apresentaram maior quantidade de PUFAs e melhor a relação n-6: n-3.

Structure of the Conjugated Linoleic Acid-Paclitaxel Conjugate Self-Assembled Nanoparticles / 中国药学杂志

OBJECTIVE: To prepare, the conjugated linoleic acid-paclitaxel conjugate self-assembled nanoparticles (CLA-PTX NPs) by nanoprecipitation. METHODS: The Dynamic light scattering, nuclear magnetic resonance spectroscopy, raman spectroscopy, fourier transform infrared spectroscopy and nitrogen element distribution of CLA-PTX NPs were studied. RESULTS: The hydroxyl groups (C-4 and C-10 of PTX) and the acetyl groups (C-1 and C-7 of PTX) were on the surface of CLA-PTX NPs, CLA carbon chain, the benzene ring (C-2 and C-3' of PTX) and the amide bond (C-3' of PTX) were inside the CLA-PTX NPs. CONCLUSION: It is speculated that the self-assembly of CLA-PTX is that the non-polar CLA carbon chain spontaneously aggregates inward due to hydrophobic interaction, and the hydrophilic oxygen-containing groups of PTX (hydroxyl group and carbonyl group) are on the surface of the nanoparticle to form nanoparticles.

Interactions between Cannabis Fructus and human gut microflora / 中草药

Objective To explore the characteristics of the interactions between traditional laxative medicine Cannabis Fructus and human gut microflora. Methods HPLC method was used to determine the content of the main unsaturated fatty acids linoleic acid and linolenic acid in Cannabis Fructus Decoction. At the same time, solid culture and liquid culture in vitro anaerobic culture method were combined with 16 S rRNA technology to analyze the interactions between Cannabis Fructus Decotion and human gut microflora. Moreover, the metabolits of linoleic acid and linolenic acid in Cannabis Fructus Decoction by human intestinal microflora were determined using HPLC method. At the same time, the possible conjugated linolenic acid and linoleic acid were determined. Results Cannabis Fructus Decoction promoted the growth of Proteobacteria significantly, which showed that Escherichia-shigella was significantly increased (P < 0.01), but the growth of Bacteroidetes was decreased (P < 0.01), and the content of unsaturated fatty acids linoleic acid and linolenic acid in Cannabis Fructus Decoction were reduced after being incubated with human intestinal bacteria, and the metabolites were conjugated linoleic acid and conjugated linolenic acid. Conclusion The interactions between Cannabis Fructus Decoction and human intestinal microflora are obvious. The Chinese medicine can change the structure of the gut microflora, and the gut microflora can metabolize the drug components. This analysis method partially restores the pharmacokinetics process of the oral administration drug in the human intestinal tract. It could provide a new insight of the mechanism research of Cannabis Fructus.

Conjugated linoleic acid improves glucose and lipid metabolism in diabetic mice / 南方医科大学学报

OBJECTIVE@#To analyze the effect of conjugated linoleic acid (CLA) on glucose and lipid metabolism in obese diabetic (db/db) mice.@*METHODS@#db/db mice were randomized for treatment with saline or CLA mixture administered intragastrically. The changes in body weight, dietary intake, water intake, oral glucose tolerance, triglyceride and total cholesterol were recorded after the treatments. HE staining and oil red O staining were used to assess liver pathologies and fatty acid content. The expression levels of PPARα, PPARγ, CD36, CHREBP and SREBP-1c were detected using real-time PCR and Western blotting. HepG2 cells were treated with CLA and linoleic acid and the expressions of PPARα, ACC, P-ACC, and CD36 were detected; the level of acetyl-CoA in the cell supernatant was detected using ELISA.@*RESULTS@#CLA treatment obviously reduced the dietary and water intake of db/db mice, effectively reduced the body weight and decreased serum triglyceride and cholesterol levels ( < 0.05). CLA significantly reduced fasting blood glucose, increased glucose tolerance, reduced the accumulation of lipid droplets in the liver and improved lipid metabolism in db/db mice. The mice showed significantly increased expression of PPARα ( < 0.05) and lowered CD36 expression ( < 0.001) in the liver after CLA treatment. Cellular experiments showed that CLA significantly up-regulated PPARα ( < 0.001) and P-ACC and decreased the expression of CD36 ( < 0.01). ELISA showed that acetyl-CoA was significantly up-regulated in the cells after CLA treatment ( < 0.01).@*CONCLUSIONS@#The mixture of two conjugated linoleic acid isomers can reduce fasting blood glucose, increase glucose tolerance and improve glycolipid metabolism in db/db mice by enhancing the expression of PPARα, increasing P-ACC and inhibiting CD36 expression.

Risk Assessment of "Other Substances" – Conjugated Linoleic Acids

The Norwegian Scientific Committee for Food Safety (Vitenskapskomiteen for mattrygghet, VKM) has, at the request of the Norwegian Food Safety Authority (Mattilsynet; NFSA), assessed the risk of "other substances" in food supplements and energy drinks sold in Norway. VKM has assessed the risk of doses given by NFSA. These risk assessments will provide NFSA with the scientific basis for regulating the addition of "other substances" to food supplements and other foods. "Other substances" are described in the food supplement directive 2002/46/EC as substances other than vitamins or minerals that have a nutritional or physiological effect. It is added mainly to food supplements, but also to energy drinks and other foods. VKM has not in this series of risk assessments of "other substances" evaluated any potential beneficial effects from these substances, only possible adverse effects. The present report is a risk assessment of conjugated linoleic acids (CLAs), and is based on previous risk assessments of CLAs and articles retrieved from literature searches. According to information from the NFSA, CLAs are ingredients in food supplements sold in Norway, and NFSA has requested a risk assessment of the following doses of CLAs in food supplements: 3.0, 3.25 and 3.5 g/day. The daily intakes in Norway of CLAs range between 20 and 170 mg (MoBa 2008, version 4). The CLAs are mostly studied in overweight and obese subjects because of their claimed effects to reduce body weight. CLAs constitute a group of isomeric fatty acids mostly produced by bacterial fermentation in the gut. In the human diet, meat (mainly isomers c9,t11 and t10,c12) and dairy products (mainly isomer c9,t11) are main sources of CLAs. The various isomers may have different metabolic effects. In the food supplements evaluated by EFSA (EFSA, 2010 a; EFSA, 2010 b; EFSA, 2012), Clarinol® and Tonalin®, the t10,c12 and the c9,t11 isomers are present in about equal proportions. In research articles not all authors are consistent in reporting what they have studied, so in this report we sometimes do not distinguish between these isomers; hence they are referred collectively to as CLAs if it is not specified. Most of the cited studies have tested supplemental CLAs in doses of about 3.5 g/day, but ranging from 0.7 to 6.0 g/day. In most of the randomised controlled trials (RCTs) there have been no significant differences in adverse effects between the placebo and CLA-groups. Concerns about indications of an unfavourable effect on biomarkers of lipid- and carbohydrate metabolism in obese men with metabolic syndrome as well as unfavourable effect on antioxidant status; increased markers of oxidative stress after consumption of supplemental CLAs have been reported in previous studies. No clear dose-response effects have been found. It is concluded that supplemental CLAs may impair lipid- and carbohydrate metabolism in obese men with the metabolic syndrome. Intake of supplemental CLAs by lactating women may reduce fat content in breastmilk, and intake of supplemental CLAs by pregnant women may reduce birth weight and –length among their offsprings. Only one randomised controlled trial has included children (6-10 years). These children were all overweight or obese, subjects likely to have a different CLA-metabolism/-effect than normal-weight subjects. VKM considers that current data are too incomplete to evaluate any doses of CLAs for children and adolescents. There are few long-term studies, and adverse health effects were not primary outcomes in these studies. Based on available data no conclusions can be drawn for supplemental use of CLAs longer than six months. VKM concludes that: In adults (≥18 years), the specified doses 3.0, 3.25 and 3.5 g/day CLAs in food supplements are considered to be unlikely to cause adverse health effects if used for up to six months. CLA may cause lipid- and carbohydrate disturbances in obese men with metabolic syndrome as well as in overweight/obese subjects with type 2 diabetes. Use of CLA supplements in lactating and pregnant women may cause reduction in milk production and in the content on milk fat and cause decreased birth weight andlength in their off-springs. No conclusion can be made for children and adolescents. Data are insufficient to conclude regarding use of CLAs for more than six months.

Composição de ácidos graxos do queijo e leite de vacas alimentadas com casca de banana / Fatty acid composition of cheese and milk of cows fed with banana peel

Objetivou-se avaliar os níveis de casca de banana seca ao sol na dieta de vacas F1 Holandês x Zebu sobre o perfil de ácidos graxos do leite e do queijo minas frescal. Os tratamentos foram constituídos de 0, 15, 30, 45 e 60% de substituição da silagem de sorgo pela casca de banana. O delineamento experimental foi em dois quadrados latinos 5 x 5 simultâneos. As amostras de leite e queijo foram analisadas quanto ao perfil de ácidos graxos por cromatografia gasosa. Observou-se efeito quadrático para o somatório de ácidos graxos poli-insaturados do leite, com valor máximo no nível de 23,54% de substituição. Houve efeito linear decrescente para os ácidos graxos C15:0 iso e C16:0 iso. Os ácidos graxos heneicosanoico, linoleico, linoleico conjugado e araquidônico apresentaram efeito quadrático. Não houve efeito das dietas sobre os ácidos graxos no queijo. A substituição de até 60% da silagem de sorgo por casca de banana na dieta de vacas em lactação pode ser alternativa para produção e processamento do leite, quando se considera a melhora no valor nutricional da fração lipídica do leite e o aumento dos teores de ácido linoleico conjugado.(AU)

This study aimed to evaluate the inclusion levels of dry banana peel in the sun in the diet of F1 Holstein x Zebu cows on the profile of fatty acids of milk and Minas fresh cheese. The diets were composed of 0, 15, 30, 45, and 60% replacement of sorghum silage by banana peel. The experimental design was Latin squares, simultaneous, 5 x 5. Samples of milk and cheese were analyzed for fatty acid composition by gas chromatography. Quadratic effect for the sum of milk polyunsaturated fatty acids, with the maximum level of 23,54% replacement. There was a decreasing linear effect for C15:0 iso fatty acids and C16: 0 iso. The heneicosanoic fatty acids, linoleic, conjugated linoleic and arachidonic presented quadratic effect. There was no effect of diets on fatty acids in cheese. Replacement of up to 60% of the sorghum silage of a banana peel in the diet of cows can be an alternative to milk production and processing when considering the improvement in the nutritional value of the milk lipid fraction and increase of the levels of conjugated linoleic acid.(AU)

Efeito da adição do ácido linoleico conjugado no cultivo in vitro de embriões F1 Holandês x Zebu na sobrevivência pós-vitrificação / Effect of conjugated linoleic acid addition in in vitro culture medium in F1 Holstein X Zebu embryo survival post vitrification

Avaliou-se o efeito da adição do ácido linoleico conjugado (CLA) ao meio de cultivo in vitro na viabilidade pós-vitrificação de embriões F1 Holandês x Zebu. Foram utilizados três meios de cultivo: controle (n=340 oócitos): meio SOF e soro fetal bovino (SFB), sem o CLA; SFB+CLA (n=359 oócitos): meio SOF, SFB e CLA; CLA (n=339 oócitos): meio SOF e CLA, sem o SFB. Todos os blastocistos produzidos foram submetidos à vitrificação, pelo método de Open Pulled Straw. Quinze blastocistos de cada tratamento foram fixados para quantificação lipídica por coloração com Sudan Black B. Para avaliar a viabilidade embrionária, foi observada a capacidade de reexpansão e eclosão pós-aquecimento dos embriões (controle=27; SFB+CLA=30; CLA=17). Foram realizadas transferências em um ou dois embriões por receptora para avaliação da sobrevivência in vivo: T1 [receptoras que receberam um blastocisto (n=17 embriões, sendo controle=5, SFB+CLA=6 e CLA=6)]; T2 [receptoras que receberam dois blastocistos, (n= 54 embriões, sendo controle=18, SFB+CLA=14 e CLA=22)]. Não houve diferença nas taxas de clivagem (62,1%; 74,0%; 74,0% para controle; SFB+CLA; CLA, respectivamente), produção de blastocistos em relação aos clivados (59,7%; 47,7%; 38,3% para controle; SFB+CLA; CLA, respectivamente) e produção de blastocistos em relação ao total de oócitos (37,1%; 35,4%; 28,3% para controle; SFB+CLA; CLA, respectivamente) (P>0,05). Houve diminuição de gotículas lipídicas nos embriões cultivados em meio suplementado com CLA em relação aos embriões cultivados na presença do SFB e na ausência do CLA (P<0,05). A taxa de reexpansão foi maior no grupo controle (70,4%) em relação ao CLA (47,1%) e menor no grupo SFB+CLA (43,3%) (P<0,05). O CLA foi eficaz em reduzir a deposição de lipídeos intracitoplasmáticos nas células embrionárias, porém não houve diferença de viabilidade após a desvitrificação dos embriões.(AU)

The effect of adding conjugated linoleic acid (CLA) to the culture media on the viability after cryopreservation of F1 Holstein X Zebu embryos was evaluated. Three different culture media were tested: control (n = 340 oocytes): SOF medium and fetal bovine serum (FBS) without the CLA; FBS + CLA (n = 359 oocytes): SOF, FBS and CLA; CLA (n = 339 oocytes): SOF and CLA without the FBS. The produced blastocysts were subjected to vitrification, by the Open Pulled Straw method. Fifteen blastocysts per treatment were fixed for lipid quantification by staining with Sudan Black B. Embryo re-expansion and hatching capability were used to assess viability (control = 27; FBS + CLA = 30; CLA = 17). Transfers of one or two embryos to recipients were performed to evaluate in vivo survival: T1 [recipients that received one blastocyst (n=17 embryos, Control=5, FBS+CLA=6 and CLA=6)]; T2 [recipients that received two blastocysts (n =54 embryos, Control=18, FBS+CLA=14 and CLA=22)]. There was no difference in cleavage rate (62.1%; 74%; 74% for Control; FBS + CLA, CLA, respectively), blastocyst production in relation to the cleaved structures (59.7%; 47.7%; 38 3% for Control; FBS + CLA, CLA, respectively) and blastocyst production relative to the total oocytes (37.1%, 35.4%, 28.3% for Control; FBS + CLA, CLA, respectively) between treatments (P> 0.05). A reduction of lipid droplets was observed in embryos cultured in medium supplemented with CLA compared to embryos cultured in the FCS in the absence and presence of CLA (P <0.05). The reexpansion rate was higher in the Control group (70.4%) compared to the CLA (47.1%) and lowest for FBS+CLA (43.3%) (P<0.05). The hatching rates were similar among treatments, 42.1%; 23.1%; 25% for control; SFB + CLA; CLA respectively (P>0.05). Only one pregnancy was observed in early and confirmatory diagnosis, as the result of a Control group embryo transfer. Although embryos cultured with CLA have shown smaller intracytoplasmic lipid content, no difference was observed in viability following vitrification between treatments.(AU)

Liver metabolic changes induced by conjugated linoleic acid in calorie-restricted rats

ABSTRACT Objective Complexes like conjugated linoleic acid (CLA) reduce the percentage of body fat by increasing energy expenditure, fat oxidation, or both. The aim of this study was to verify if CLA is able to mimic caloric restriction (CR), and determine the effects of CLA on liver metabolic profile of young adult male Wistar rats. Materials and methods We divided 36 animals into the following groups: 1) Control; 2) CLA (1% of daily food intake, 21 days, orogastric intubation); 3) Restr (fed 60% of the diet offered to controls); and 4) CLA Restr. Liver tissues were processed for biochemical and molecular or mitochondrial isolation (differential centrifugation) and blood samples were collected for biochemical analyses. Results Treatment of the animals for 21 days with 1% CLA alone or combined with CR increased liver weight and respiration rates of liver mitochondria suggesting significant mitochondrial uncoupling. We observed a decrease in adipose tissue leading to insulin resistance, hyperinsulinemia, and hepatic steatosis due to increased liver cholesterol and triacylglycerol levels, but no significant effects on body mass. The expression of hepatic cellular connexins (43 and 26) was significantly higher in the CLA group compared with the Control or Restr groups. Conclusion CLA does not seem to be a safe compound to induce mass loss because it upregulates the mRNA expression of connexins and induces hepatic mitochondrial changes and lipids disorders.

Perfil de ácidos graxos de iogurte produzido com diferentes culturas bacterianas / Fatty acid profile of produced with different cultures yogurt startes

Objetivou-se avaliar o perfil de ácidos graxos do iogurte produzido com diferentes culturas fermentadoras, seu comportamento durante o processo fermentativo e seu valor nutricional (índices aterogênico e trombogênico). Testaram-se três formulações de culturas fermentadoras: Padrão (Lactobacillus bulgaricus e Streptococcus thermophilus); Padrão + probiótico (Lactobacillus acidophilus e Bifidobacterium sp) e probiótico. Amostras do leite obtidas durante e após a fermentação, foram analisadas quanto ao perfil de ácidos graxos. A gordura foi extraída por Bligh e Dyer, a preparação dos ésteres metílicos por Hartman e Lago, a determinação e quantificação por cromatografia gasosa. As diferentes culturas fermentadoras não tiveram efeito sobre o perfil de ácidos graxos do iogurte produzido. O teor de ácido linoleico conjugado não diferiu entre os tratamentos. Observou-se uma variação nos teores de palmítico, palmitoléico e α-linolênico durante o processo fermentativo. Entretanto, a utilização de diferentes culturas não teve efeito na relação n6/n3 e nos índices aterogênico (IA) e trombogênico (IT) entre os tratamentos e desses com o leite.

The objective was to evaluate the fatty acid profile of yogurt produced with different fermenting cultures, their behavior during the fermentation process and its nutritional value (atherogenic and trombogenic indexes). Tree formulations were tested fermenting cultures: Standard (Lactobacillus bulgaricus e Streptococcus thermophilus); Standard + probiotic (Lactobacillus acidophilus and Bifidobacterium sp) and probiotic. Samples of the milk obtained during and after fermentation were analyzed for their fatty acid profile. The fat was extracted by Bligh and Dyer, the preparation of the methyl esters and by Hartman and Lago, determination and quantification by gas chromatography. The different fermenting cultures had no effect on the fatty acid profile of the produced yogurt. The conjugated linoleic acid content did not differ between treatments. There was a variation in the levels palmitic, palmitoleic acid and α-linolenic during the fermentation process. However, the use of different cultures had no effect on the relationship n6/n3 and atherogenic index (IA) and thrombogenic (IT) between these treatments and with the milk.

Weight Management Effects of a Mixture of Conjugated Linoleic Acid and L-Carnitine in Diet Induced Obese Rats.

Aims: To examine simultaneous effects of Conjugated Linoleic Acid (CLA) and L-carnitine (LC) on weight gain in diet induced obese rats. Study Design: Experimental study. Place and Duration of Study: Department of Nutrition, Faculty of Para-Medical Sciences, Ahvaz Jundishapur University of Medical Sciences (January 2014 to January 2015). Methodology: Forty male Wistar rats were randomly divided into two groups: Normal fat diet (n=8), and High fat diet (HFD) (n=32). After eight weeks, the second group maintained HFD and was subdivided into 4 categories: Corn Oil group, 500 mg CLA, 200 mg LC, and 500 mg CLA+ 200 mg LC (all doses per kg body weight), which were administered by oral gavage for four weeks. Body weights were measured and recorded weekly by means of a digital scale. SPSS Version 16 was used for statistical analysis. Results: At the end of eighth week, a significant difference in weights was observed between HFD (295.43±5.36 gr) and NFD (246.38±6.48 gr) group. After four weeks, LC significantly reduced weight gain by 7.5% (P = .047). Trend of weight gain in CLA and LC + CLA groups were decelerated (24 and 25 gr respectively), but it was statistically insignificant (P = .08, .12 respectively). Conclusion: Findings of this experimental study showed that a high fat diet led to obesity and combined LC and CLA could decelerate weight gain to some extent. However, it needs further work to validate reliability in human.

Conjugated linoleic acid in milk and fermented milks: variation and effects of the technological processes / Ácido linoleico conjugado en leche y leches fermentadas: variabilidad y efectos de los procesos tecnológicos

Background: Conjugated linoleic acid (CLA) is a generic term used to describe a group of geometric and positional isomers of linoleic acid with a conjugated double bond system. CLA-isomers have been widely studied because of their important biological activity and their protective effects against several diseases, such as obesity, atherosclerosis, chronic inflammatory diseases, and cancer. Consequently, these biomolecules have attracted much attention from the dairy industry, since they are naturally found in ruminants' milk, and because the development of CLA-enriched dairy foods can be a good economic opportunity given the growth of the functional foods market, in which the dairy industry plays an important role. Objectives: This work presents a comprehensive review of the following aspects: (i) The synthesis and concentration of the CLA-isomers in milk, and the main strategies employed to increase their content in a natural manner; (ii) The influence of the main technological treatments applied to milk on the concentration of CLA-isomers; and (iii) The effects of milk fermentation on the content of CLA-isomers, and the challenges of this technological process, which has been though as a promissory alternative to naturally increase the content of CLA in fermented dairy products. Methods: Information available in various databases was reviewed. A total of 103 articles were selected on the basis of their relevance and scientific-technical quality. Results: The CLA concentration in cows' milk normally ranges between 2 and 37 mg/g fat, and is mainly affected by the dietary regime offered to the animals. From the total CLA-isomers, rumenic acid represents between 75 and 90%. The technological processes normally applied to milk (thermal processing, high pressure processing, and fermentation) might cause slight changes on the CLA concentration, but the mechanisms causing these changes have not been still established. The increase in CLA concentration by milk fermentation is strain-dependent, because of the different linoleate isomerase activity of the species. . Conclusions: Although several studies have reported increases in the concentration of CLA in milk and fermented milks in a natural manner, they are fairly moderate, and the obtained levels of CLA are significantly lower than those recommended to achieve therapeutic effects

Antecedentes: El ácido linoleico conjugado (CLA) es un término genérico utilizado para describir el grupo de isómeros geométricos y posicionales del ácido linoleico con un sistema de dobles enlaces conjugados. Los isómeros de CLA han sido ampliamente estudiados debido a su importante actividad biológica y a sus efectos protectores contra varias enfermedades, como la obesidad, arteriosclerosis, enfermedades inflamatorias crónicas y el cáncer. En consecuencia, estas biomoléculas han despertado mucho interés en la industria láctea, dado que están presentes naturalmente en la leche de rumiantes, y porque el desarrollo de productos lácteos enriquecidos con CLA puede representar una oportunidad económica interesante, dado el crecimiento del mercado de alimentos funcionales, en el cual la industria láctea tiene una participación importante. Objetivos: En este trabajo se presenta una revisión detallada de los siguientes aspectos: (i) El origen de los isómeros de CLA en la leche, sus concentraciones promedio y las principales estrategias utilizadas para incrementar su contenido de manera natural; (ii) La influencia de los principales tratamientos tecnológicos aplicados a la leche en la concentración de los isómeros del CLA; y (iii) Los efectos de la fermentación de la leche en el contenido de isómeros de CLA, y los retos de este proceso tecnológico concebido como promisorio para aumentar naturalmente el contenido de CLA en leches y productos lácteos fermentados. Métodos: Se revisó la información disponible en varias bases de datos. Un total de 103 artículos fueron seleccionados con base en su pertinencia y calidad técnico-científica. Resultados: La concentración de CLA en la leche de vaca normalmente oscila entre 2 y 37 mg/g grasa, y es afectada principalmente por la dieta suministrada a los animales. Del total de isómeros de CLA, el ácido ruménico representa entre 75 y 90%. Los procesos tecnológicos aplicados normalmente a la leche (procesado térmico, procesamiento por altas presiones y fermentación) pueden causar ligeras modificaciones en la concentración de CLA, pero los mecanismos que causan estos cambios no han sido aún establecidos. El incremento en la concentración de CLA por fermentación de la leche es dependiente de la cepa, debido a diferencias en la actividad de la linoleato isomerasa de las especias. Conclusiones: Aunque varios estudios han reportado incrementos en la concentración de CLA en leche y leches fermentadas de manera natural, estos son bastante moderados, y los niveles de CLA obtenidos son significativamente menores que los recomendados para alcanzar los efectos terapéuticos.

Study on in vitro Anticancer Activity of Conjugated Linoleic Acid-Gemcitabine Conjugate / 中国药房

OBJECTIVE:To study in vitro anticancer activity of conjugated linoleic acid-gemcitabine conjugate (CLA-GEM). METHODS:IC50 of different tumor cells (breast cancer MCF-7 cell,breast cancer MDA-MB-231 cell,lung cancer A549 cell, small cell lung cancer NCI-H446 cell,glioma C6 cell)were investigated after treated with different concentrations(0.001-100μmol/L)of CLA-GEM and gemcitabine(GEM)for 72 h;survival rates of MCF-7 cell were investigated after treated with above so-lution for 24,48 and 72 h. The dependence of 0.001-100 μmol/L CLA-GEM and GEM to nucleoside transporter was investigated (by IC50)through MCF-7 cells and MDA-MB-231 cells treated with nucleoside transporter inhibitors(NBMPR,100 μmol/L)and di-pyridamole(4 μg/ml). The change of MCF-7 cell cycle was investigated after treated with 1 μmol/L CLA-GEM and GEM for 24 h. RESULTS:Compared with GEM,IC50 of MCF-7,MDA-MB-231 and NCI-H446 cells became lower after treated with CLA- GEM (P0.05). Survival rate of MCF-7 cells de-creased significantly after treated with GEM for 48 h and CLA-GEM for 24 h. Survival rate of MCF-7 cells was the lowest,being 21% after treated with GEM for 72 h,while tumor cells were sacrificed by CLA-GEM completely. Compared with GEM or CLA-GEM,IC50 of MCF-7 and MDA-MB-231 cells increased significantly after treated with NBMPR,dipyridamole combined with GEM (P0.05). Compared with GEM,CLA-GEM could prolong 6% of S stage of MCF-7 cells (P<0.01). CONCLU-SIONS:Compared with GEM,CLA-GEM exhibits significant antitumor activity and rapid action,and it isn’t influenced by nucle-ic acid transportation.

Characterization of Conjugated Linoleic Acid-Producing Lactic Acid Bacteria as Potential Probiotic for Chicken

Aims: Dietary intake of conjugated linoleic acid (CLA) by human is insufficient to exhibit properties of anti-cancer, antiinflammatory, anti-atherosclerosis, anti-obesity and enhancing immune system. Thus, enrichment of CLA in chicken by bacteria is a suggestion to solve the problem. It would be an advantage to have bacteria capable of producing CLA and has probiotic potential in chicken. Thus, probiotic properties of CLA-producing bacteria were accessed in this study. Methodology and results: In this study, 47 lactic acid bacteria (LAB) isolated from gastrointestinal tract of chickens were screened for conjugated linoleic acid (CLA) production. Lactobacillus salivarius strain P2, Enterococcus faecium strain P1 and Lactobacillus agilis strain P3 were shown to produce 21.97, 23.35 and 31.08 µg/mL of CLA in MRS broth containing free linoleic acid (0.5 mg/mL) and 2% (w/v) Tween 80, respectively. Lactobacillus salivarius strain P2, E. faecium strain P1 and L. agilis strain P3 were found to be able to tolerate 0.3% oxgall (Difco, France) and pH 2.5. Lactobacillus agilis strain P3 and L. salivarius strain P2 showed better acid tolerance compared to E. faecium strain P1. Besides that, L. agilis strain P3 and L. salivarius strain P2 were resistant to two out of eight types of antibiotics tested, able to produce 220.04 mM lactic acid and 200.17 mM of lactic acid, respectively. Enterococcus faecium strain P1 was resistant to five out of eight types of antibiotic tested, produced 90.39 mM lactic acid and showed hemolytic activity. Only L. agilis strain P3 can produce acetic acid at a concentration of 2.71 mM. Conclusion, significance and impact of study: These results showed that the CLA-producing L. salivarius strain P2 and L. agilis strain P3 could be potential probiotic bacteria for chickens, which may eventually lead to production of chicken with better meat quality.

Preeclampsia prevention: a case-control study nested in a cohort / La prevención de la preeclampsia: un estudio de casos y controles anidado en una cohorte

Introduction: Preeclampsia is the main complication of pregnancy in developing countries. Calcium starting at 14 weeks of pregnancy is indicated to prevent the disease. Recent advances in prevention of preeclampsia endorse the addition of conjugated linoleic acid. Objective: To estimate the protective effect from calcium alone, compared to calcium plus conjugated linoleic acid in nulliparous women at risk of preeclampsia. Methods: A case-control design nested in the cohort of nulliparous women attending antenatal care from 2010 to 2014. The clinical histories of 387 cases of preeclampsia were compared with 1,054 normotensive controls. The exposure was prescriptions for calcium alone, the first period, or calcium plus conjugated linoleic acid, the second period, from 12 to 16 weeks of gestational age to labor. Confounding variables were controlled, allowing only nulliparous women into the study and stratifying by age, education and ethnic group. Results: The average age was 26.4 yrs old (range= 13-45), 85% from mixed ethnic backgrounds and with high school education. There were no differences between women who received calcium carbonate and those who did not (OR= 0.96; 95% CI= 0.73-1.27). The group of adolescents (13 to 18 yrs old) in the calcium plus conjugated linoleic acid was protected for preeclampsia (OR= 0.00; 95% CI= 0.00-0.44) independent of the confounder variables. Conclusions: 1. Calcium supplementation during pregnancy did not have preventive effects on preeclampsia. 2. Calcium plus Conjugated Linoleic acid provided to adolescents was observed to have preventive effect on Preeclampsia.

Introducción: La preeclampsia es la principal causa de mortalidad materna y bajo peso al nacer en países en vías de desarrollo. Empezar la suplementación de calcio en la semana 14 de gestación es indicada para prevenir la enfermedad. Recientes avances en prevención de preeclampsia han sugerido la suplementación de calcio y la combinación de calcio con ácido linoleico conjugado. Objetivo: Estimar el efecto protector de la suplementación de calcio (CC), comparado con la suplementación de calcio más ácido linoleico conjugado (CC+ALC) en mujeres embarazadas primigravidas con relación al desarrollo de preeclampsia. Métodos: Se realizó un estudio de casos y controles anidado en una cohorte retrospectiva de mujeres embarazadas primigravidas que asistieron al programa de control prenatal entre el año 2010 hasta el años 2014. La historia clínica de 387 casos de preeclampsia fueron comparadas con 1,054 controles en pacientes embarazadas primigestantes, normotensas. Las gestantes expuestas fueron consideradas como aquellas gestantes que recibieron solo calcio, en el primer periodo de evaluación, o calcio más ácido linoleico conjugado, segundo periodo de evaluación, desde las semanas 12 a la 16 del embarazo. Los posibles factores de confusión se controlaron admitiendo solo las primigestantes y estratificando, por edad, educación y grupo étnico de la paciente. Resultados: La edad promedio de las pacientes fue de 26.4 años (rango= 13-45), 85% con etnia mestiza y educación secundaria completa. La exposición a CC+ALC tuvo un efecto protector en las adolescentes (13 a 18 años) (OR= 0.00, IC 95%= 0.00-0.44; p= 0.005), mientras que la exposición a CC no modificó la incidencia de preeclampsia (OR= 0.96, IC 95%= 0.73-1.27; p= 0.82). Conclusiones: 1. La suplementación de solo calcio durante el embarazo no tuvo efecto preventivo para la preeclampsia, 2. La suplementación con calcio y ácido linoleico conjugado previno la aparición de preeclampsia en adolescentes.

Qualidade da carne de bovinos terminados em pastejo / Quality of bovine meat finished in grazing / Calidad de la carne de bovinos terminados en pastaje

A carne bovina é uma importante fonte de proteína para alimentação humana, e as exportações de carne contribuem significativamente com a balança comercial brasileira. Entretanto, a conquista e consolidação de novos mercados depende da compreensão que o consumidor tem da qualidade da carne. Com o consumidor mais consciente, o foco da qualidade da carne vem passando do produtor e da indústria (peso da carcaça, rendimento de carcaça, etc.) para o consumidor, com avaliação das características organolépticas e valor nutricional. Apesar do confinamento de bovinos ter crescido nos últimos anos, a terminação a pasto é predominante no país e o rebanho é composto basicamente por animais zebuínos. Esta modalidade de terminação garante a carne características qualitativas particulares, e embora animais terminados em pastejo apresentem carne menos macia e com menos marmoreio, tais características podem ser melhoradas por meio do manejo nutricional e cruzamentos. Já o valor nutritivo da carne tende a ser melhor em animais terminados em pastejo, apresentando menor teor de gordura, e com melhor perfil lipídico, com maior concentração de ácidos graxos insaturados, ácido linoleico conjugado (CLA) e menor relação Ω6:Ω3. Tais características tornam a carne de animais produzidos em pastejo um alimento funcional, podendo ser trabalhado para agregar valor à carne brasileira, que poderá atender a nichos específicos de mercado.

Beef is an important source of protein for human consumption, and meat exports significantly contribute to the Brazilian trade balance. However, the conquest and consolidation of new markets depend on the understanding the consumer has of the quality of meat. With consumers being more aware, the focus of quality meat is shifting from the producer and the industry (carcass weight, carcass yield, etc.) to the consumer, with the evaluation of organoleptic characteristics and nutritional value. Despite the growth in cattle confinement in recent years, the termination in grazing is prevalent in the country and the flock is basically composed of zebu animals. This form of termination ensures the meat presents particular quality characteristics, and although animals finished on grazing have less soft flesh and less marbling, such characteristics can be improved through nutrition management and cross-breeding. The nutritional value of the meat, on the other hand, tends to be better in animals finished on grazing, with less fat, and better lipid profile with higher concentration of unsaturated fatty acids, conjugated linoleic acid (CLA) and lower Ω6:Ω3 relationship. These characteristics make the meat produced from animals in grazing in a functional food, and can bring added value to the Brazilian beef, which can cater to specific niche markets.

La carne bovina es una importante fuente de proteína para la alimentación humana, y las exportaciones de carne contribuyen significativamente con la balanza comercial brasileña. Sin embargo, la conquista y consolidación de nuevos mercados depende de la comprensión que el consumidor tiene de la calidad de la carne. Con el consumidor más consciente, el foco de la calidad de la carne viene pasando del productor y de la industria (peso de caparazón, rendimiento de caparazón, etc.) para el consumidor, con evaluación de las características organolépticas y valor nutricional. A pesar del confinamiento de bovinos haber crecido en los últimos años, la terminación a pasto es predominante en el país y el rebaño es compuesto básicamente por animales cebús. Esta modalidad de terminación garantiza a la carne características cualitativas particulares, y aunque los animales terminados en pastaje presenten carne menos blanda y con menos marmoleo, tales características pueden ser mejoradas a través del manejo nutricional y cruzamientos. Ya el valor nutritivo de la carne tiende a ser mejor en animales terminados en pastaje, presentando menor tenor de grasa, y con mejor perfil lipidio, con mayor concentración de ácidos grasos insaturados, ácido linoleico conjugado (CLA) y menor relación Ω6:Ω3. Tales características hacen la carne de animales producidos en pastaje un alimento funcional, pudiendo ser trabajado para agregar valor a la carne brasileña, que podrá atender a nichos específicos de mercado.

Ácidos graxos e colesterol da carne de cordeiros confinados recebendo dietas contendo fontes lipídicas e submetidos à restrição e realimentação / Fatty acids and cholesterol of meat from lambs fed diets containing lipid sources and subjected to restriction and refeeding

Foram avaliados os efeitos da inclusão de grãos de girassol ou gordura protegida na dieta e da restrição e realimentação sobre a área de olho de lombo, espessura de gordura subcutânea, a composição centesimal, o teor de colesterol e a composição em ácidos graxos da gordura intramuscular do Longissimus lumborum de cordeiros, distribuídos em delineamento inteiramente casualizado, em esquema fatorial (3 dietas x 2 manejos de alimentação). O colesterol da gordura intramuscular de cordeiros alimentados com a dieta contendo gordura protegida (28,5mg 100 g^-1) foi menor (P<0,05) que o do controle (36,8mg 100g^-1) e grãos de girassol (38,1mg 100g^-1). O manejo de restrição alimentar e realimentação não modificaram (P>0,05) o perfil dos ácidos graxos, porém foi detectado que a dieta contendo grãos de girassol elevou (P<0,05) a razão polinsaturado/saturado, provavelmente pela superioridade (P<0,05) de 20% na proporção de polinsaturados, reflexo direto do aumento na concentração do ácido linoleico. A inclusão de fontes lipídicas na dieta de ovinos é ferramenta que contribui para melhorar a qualidade da gordura intramuscular de cordeiros confinados, considerando que a gordura protegida reduz o teor de colesterol e que os grãos de girassol aumentam a concentração de ácidos graxos polinsaturados. O manejo de alimentação com período de restrição e realimentação não altera a composição centesimal e a qualidade da gordura intramuscular.

It was evaluated the effects of sunflower grains inclusion or protected fat in the diet and compensatory growth on the loin eye area, subcutaneous fat thickness, chemical composition, cholesterol concentration and fatty acid composition of intramuscular fat of Longissimus lumborum of lambs distributed in a completely randomized design in factorial scheme (3 diets x 2 feeding management). Intramuscular cholesterol from lambs fed with diet containing protected fat (28.5mg 100g^-1) was lower (P<0.05) than that of the control (36.8mg 100g^-1) and sunflower grains (38.1mg 100g^-1). The restriction and refeeding didn't cause change (P>0.05) in the fatty acids profile, but diet containing sunflower grains increased polyunsaturated/saturated ratio due to(P<0.05) the superiority of 20% in the proportion of polyunsaturated, reflecting directly the increase in linoleic acid. Inclusion of lipid sources in the diet of feedlot sheep is a tool that helps to improve the quality of intramuscular fat of lambs, whereas the protected fat reduces cholesterol and sunflower grains elevates the concentration of polyunsaturated fatty acids. Feeding restriction and refeeding period does not alter the chemical composition and quality of intramuscular fat.

Milk fatty acid profile from grazing buffaloes fed a blend of soybean and linseed oils / Perfil de ácidos graxos do leite de búfalas a pasto recebendo uma mistura de óleo de soja e linhaça na dieta

The aim of the study was to examine the changes in milk fatty acid (FA) profile of grazing buffaloes fed either low (L, 276g/d) or high (H, 572g/d) doses of a blend (70:30, wt/wt) of soybean and linseed oils. Fourteen multiparous Mediterranean buffaloes grazing on a native pasture were fed 4 kg/day of a commercial concentrate containing no supplemental oil over a pre-experimental period of ten days. The baseline milk production and composition and milk FA profile were measured over the last three days. After this pre-experimental period the animals received the same concentrate added with either the L or H oil doses for 26 additional days. Milk yield (g/animal/day) did not differ at the start (1776 ± 522 and 1662 ± 291 for L and H, respectively, P<0.622) or at the end of the trial (4590 ± 991 and 4847 ± 447 in L and H, respectively, P<0.543). Baseline milk fat content (g/kg) averaged 77.1 (±20.5) in L and 74.3 (±9.9) in H (P<0.10) and was reduced (P<0.031) to 60.7 (±23.6) and 49.4 (±11.2) (P<0.0031) respectively after L and H with no differences between treatments (P<0.277). Baseline milk protein content (L=43.2 ± 3.4 and H= 44.3 ± 6.9g/kg) increased after oil supplementation (P<0.0001) in both L (73.2 ± 6.0g/kg) and H (68.4 ± 4.9g/kg) without differences between oil doses (P<0.123). Milk fat content of 14:0 decreased after oil supplementation only in the H treatment (5.29 to 4.03, P<0.007) whereas that of 16:0 was reduced (P<0.001) at both L (24.49 to 19.75g/100g FA) and H (25.92 to 19.17g/100g FA) doses. The reduction of total content of 12:0 to 16:0 was higher (P<0.052) in H (32.02 to 23.93g/100g FA) than L (30.17 to 25.45g/100g FA). Vaccenic acid content increased (P<0.001) from 5.70 to 13.24g/100g FA in L and from 5.25 to 16.77 in H, with higher results in the in H treatment (P<0.001). Baseline rumenic acid was sharply increased (P<0.001) in L (1.80 to 4.09g/100g FA, +127%) and H (1.60 to 4.61g/100g FA, +187%) with no differences between...

O objetivo do presente estudo foi avaliar as mudanças no perfil de ácidos graxos do leite de búfalas leiteiras recebendo baixas (B, 276g/d) ou altas (A, 572g/d) doses de uma mistura de óleos de soja e linhaça (70:30, peso/peso) na dieta. Quatorze búfalas multíparas da raça Mediterrânea, mantidas em pastagens nativas, receberam 4kg/dia de um concentrado comercial sem adição de óleo (pré-tratamento) ao longo de umperíodopré-experimental de 10 dias. A produção de leiteindividual e amostras de leite foram coletadas individualmente para determinação dos valores basais de composição e perfil de ácidos graxos do leite nos últimos trêsdias. Após este período, os animais receberam o mesmo concentrado adicionado deBou Apor 26 dias. A produção de leite (g/animal/dia) não diferiu no início (1776 ± 522 e 1662 ± 291para B e A, respectivamente (P<0,622) e no final do período experimental(4590 ±991e4847 ± 447 para LeH, respectivamente, P<0,543). O teor de gordura do leite (g/100g) apresentou valores médios de 77,1(±20,5)paraBe74,3 (±9,9)paraA(P<0,10) durante o período pré-tratamento,mas foi reduzido (P<0,03) após o fornecimento das dietas com óleo para 60,7 (± 23,6) e 49,4 (± 11,2), respectivamente para B e A, não havendo diferenças entre tratamentos (P<0,277). Os teores basais de proteína do leite (B=43,2 ± 3,4 e A=44,3 ± 6,9g/kg) aumentaram após a suplementação com óleo (P<0,0001) em ambos B (73,2 ± 6,0g/kg) e A (68,4 ± 4,9g/kg), não ocorrendo diferenças entre tratamentos (P<0,123). O teor médio basal de 14:0 na gordura do leite (4,76g/100g AG) foi reduzido após a suplementação da dieta com óleo somente no tratamento A (5,29 para 4,03, P<0,007). O teor de 16:0 na gordura do leite foi reduzido (P<0,001) nos tratamentos B (24,49 para 19,75g/100g AG) e A (25,92 para 19,17g/100g AG). A redução nos teores de 12:0+14:0+16:0 na gordura do leite foi maior (P<0,052) em A (32,02 para 23,93g/100g AG) do que em B (30,17 para 25,45g/100g AG). O teor de ácido vacênico (AV)...

ATF3 Mediates Anti-Cancer Activity of Trans-10, cis-12-Conjugated Linoleic Acid in Human Colon Cancer Cells

Conjugated linoleic acids (CLA) are a family of isomers of linoleic acid. CLA increases growth arrest and apoptosis of human colorectal cancer cells through an isomer-specific manner. ATF3 belongs to the ATF/CREB family of transcription factors and is associated with apoptosis in colorectal cancer. The present study was performed to investigate the molecular mechanism by which t10, c12-CLA stimulates ATF3 expression and apoptosis in human colorectal cancer cells. t10, c12-CLA increased an apoptosis in human colorectal cancer cells in dose dependent manner. t10, c12-CLA induced ATF3 mRNA and luciferase activity of ATF3 promoter in a dose-dependent manner. The responsible region for ATF3 transcriptional activation by t10, c12-CLA is located between -147 and -1850 of ATF3 promoter. mRNA stability of ATF3 was not affected by t10, c12-CLA treatment. t10, c12-CLA increases GSK3beta expression and suppresses IGF-1-stimulated phosphorylation of Akt. The knockdown of ATF3 suppressed expression of GSK3beta and NAG-1 and PARP cleavage. The results suggest that t10, c12-CLA induces apoptosis through ATF3-mediated pathway in human colorectal cancer cells.

Transferencia del ácido linoleico conjugado (CLA) de la leche cruda a leche en polvo y condensada / Conjugated linoleic acid transfer (CLA) from raw milk to powdered milk and condensed milk

The objective of this study was to assess the effect of processing fresh milk into dairy products on conjugated linoleic acid (CLA) content of total and individual CLA isomers (cis-9, trans-11; trans-10, cis-12; cis-10. cis-12) of dairy cow products, raw milk powdered and condensed milk. Additionally, samples of raw milk from two regions of southern Chile (Los Angeles and Los Lagos), obtained by a dairy plant were collected and analyzed. The processing of fresh milk dairy products affected the CLA and its isomers, finding a significant interaction between product type and sampling month, with the total average values of 1.35 g CLA / 100g of fatty acids (AG) in fresh milk and 1.45 and 0.93 g/ 100 g AG transferred to the milk powder and condensed respectively. As isomers, the cis-9, trans-11 had higher levels in the powdered milk that fresh milk in 7 months of the 10 months studied with values from 0.50 to 0.84 g/ 100 g AG. The isomer trans-10, cis-1 + cis-10, cis-12 CLA was found in a range of 0, 24 to 0.64 g/ 100 g AG always low in fresh milk. It is concluded that further research is necessary to elucidate the precise effect of processing and storage of milk and milk products on the content of CLA needed.

El objetivo de este estudio fue evaluar la transferencia del ácido linoleico conjugado (CLA) y de sus isómeros (cis-9, trans-1; trans-10, cis-12; cis-10 cis-12) de leche cruda a productos lácteos como la leche en polvo y la leche condensada. Se recogieron y analizaron muestras de leche cruda de dos regiones del sur de Chile (Los Ángeles y Los Lagos), recepcionada por una planta de lácteos. El procesamiento de la leche fresca a productos lácteos afectó al CLA y a sus isómeros, encontrándose una interacción significativa entre el tipo de producto y el mes de muestreo, con valores promedios de CLA total de 1,35 g/100 g AG en la leche fresca y de 1,45 y 0,93 g/100 g AG traspasados a la leche en polvo y condensada respectivamente. En cuanto a los isómeros, el cis-9, trans-11 presentó niveles más altos en leche la en polvo que el leche fresca en 7 meses de los 10 estudiados con valores que fueron de 0,50 a 0,84 g/100 g AG. El CLA trans-10, cis-1+ CLA cis-10, cis-12 se encontró en un rango de 0, 24 a 0,64 a g/100 g AG siempre bajo de la leche fresca en el caso de la leche. Se concluye que es necesario una mayor investigación para dilucidar el efecto exacto del procesamiento y almacenamiento de la leche y los productos lácteos sobre el contenido de CLA.