The role of intestinal microbiota in physiologic and body compositional changes that accompany CLA-mediated weight loss in obese mice.

OBJECTIVE: Obesity continues to be a major problem, despite known treatment strategies such as lifestyle modifications, pharmaceuticals, and surgical options, necessitating the development of novel weight loss approaches. The naturally occurring fatty acid, 10,12 conjugated linoleic acid (10,12 CLA), promotes weight loss by increasing fat oxidation and browning of white adipose tissue, leading to increased energy expenditure in obese mice. Coincident with weight loss, 10,12 CLA also alters the murine gut microbiota by enriching for microbes that produce short chain fatty acids (SCFAs), with concurrent elevations in fecal butyrate and plasma acetate. METHODS: To determine if the observed microbiota changes are required for 10,12 CLA-mediated weight loss, adult male mice with diet-induced obesity were given broad-spectrum antibiotics (ABX) to perturb the microbiota prior to and during 10,12 CLA-mediated weight loss. Conversely, to determine whether gut microbes were sufficient to induce weight loss, conventionally-raised and germ-free mice were transplanted with cecal contents from mice that had undergone weight loss by 10,12 CLA supplementation. RESULTS: While body weight was minimally modulated by ABX-mediated perturbation of gut bacterial populations, adult male mice given ABX were more resistant to the increased energy expenditure and fat loss that are induced by 10,12 CLA supplementation. Transplanting cecal contents from donor mice losing weight due to oral 10,12 CLA consumption into conventional or germ-free mice led to improved glucose metabolism with increased butyrate production. CONCLUSIONS: These data suggest a critical role for the microbiota in diet-modulated changes in energy balance and glucose metabolism, and distinguish the metabolic effects of orally delivered 10,12 CLA from cecal transplantation of the resulting microbiota.

The composition of linoleic acid and conjugated linoleic acid has potent synergistic effects on the growth and death of RAW264.7 macrophages: The role in anti-inflammatory effects.

Linoleic acid (LA) is an omega-6 polyunsaturated fatty acid. Conjugated linoleic acid (CLA) is a family of LA isomers that includes both a trans fatty acid and a cis fatty acid. Both fatty acids play a nutritional role in maintaining health. Inflammation is critical in the pathogenesis of many diseases, including cancer. This study found that the combination of LA and CLA (LA/CLA), each of which had no effect, had a strong anti-synergistic effect on inflammatory macrophage RAW264.7 cells in vitro. Cells were cultured in a DMEM containing fetal bovine serum with or without either LA, CLA, or a combination of LA/CLA. The composition of LA and CLA at a comparatively lower concentration synergistically suppressed cell growth, resulting in a reduction in cell number. The underlying mechanism of this effect was based on reduced levels of Ras, PI3K, Akt, MAPK, and mTOR and elevated levels of p21, p53, and Rb, which are associated with cell growth. In addition, the combination of LA and CLA at a lower concentration stimulated potential cell death associated with increased caspase-3 and cleaved caspase-3 levels. Notably, this composition synergistically suppressed the production of TNF-α, IL-6, and PGE2, which are a major mediator of inflammation, with lipopolysaccharide stimulation in RAW264.7 cells This effect was associated with decreased levels of COX-1, COX-2, and NF-κB p65. This study may provide a useful tool for treating inflammatory conditions with the composition of LA and CLA.

Examining performance, milk, and meat in ruminants fed with macroalgae and microalgae: A meta-analysis perspective.

This meta-analysis consolidates various related studies to identify patterns in the impact of feeding algae on performance aspects, including milk fat, milk protein, and carcass yield in several ruminant species, such as cattle, sheep, and goats. The data were collected from 67 articles that examined factors such as the type of algae (macro- and microalgae), algal species, and animal breed. Barki sheep, Moghani sheep, and Zaraibi goats demonstrated an increased average daily gain (P < 0.05) when fed with both macro- and microalgae. Conversely, sheep such as Canadian Arcott and Ile-de-France showed adverse effects on the feed conversion ratio (FCR) (P < 0.05). Elevated FCR values were observed across castrated and young animals (P < 0.05). Algae extract notably increased the hot carcass weight (P < 0.001), particularly among Moghani sheep (P < 0.001). Raw algae significantly reduced the milk fat content (P < 0.001), particularly in cattle and sheep (P < 0.001). A decrease in milk fat was particularly noticeable in lactating females of Assaf sheep, Damascus goats, and Holstein cows (P < 0.001). Overall, algae inclusion tended to decrease the milk protein content (P < 0.05), leading to reduced milk production (P < 0.001) with cumulative algae feeding in Assaf sheep. However, conjugated linoleic acid (CLA; C18:2 c9,t11-CLA and C18:2 c12,t10-CLA) and docosahexaenoic acid (DHA; C22:6n-3) mostly increased in meat and milk from Holstein cow, Assaf sheep, Dorset sheep, and Ile-de-France sheep (P < 0.01). This meta-analysis highlights the necessity for additional research aimed at optimizing the sustainable use of algae in feed for ruminants, despite the demonstrated improvements in performance and the levels of CLA and DHA found in meat and milk.

Lactobacillus plantarum Ameliorates Colorectal Cancer by Ameliorating the Intestinal Barrier through the CLA-PPAR-γ Axis.

Colorectal cancer (CRC) is the third-largest cancer worldwide. Lactobacillus can regulate the intestinal barrier and gut microbiota. However, the mechanisms of Lactobacillus that alleviate CRC remained unknown. This study aimed to explore the regulatory effect of Lactobacillus plantarum on CRC and its potential mechanism. CCFM8661 treatment significantly ameliorated CRC compared with phosphate-buffered solution (PBS) treatment in ApcMin/+ mice. In addition, conjugated linoleic acid (CLA) was proved to be the key metabolite for CCFM8661 in ameliorating CRC by molecular biology techniques. Peroxisome proliferator-activated receptor γ (PPAR-γ) was proved to be the key receptor in ameliorating CRC by inhibitor intervention experiments. Moreover, supplementation with CCFM8661 ameliorated CRC by producing CLA to inhibit NF-κB pathway and pro-inflammatory cytokines, up-regulate ZO-1, Claudin-1, and MUC2, and promote tumor cell apoptosis in a PPAR-γ-dependent manner. Metagenomic analysis showed that CCFM8661 treatment significantly increased Odoribacter splanchnicus, which could ameliorate CRC by repairing the intestinal barrier. Clinical results showed that intestinal CLA, butyric acid, PPAR-γ, and Lactobacillus were significantly decreased in CRC patients, and these indicators were significantly negatively correlated with CRC. CCFM8661 alleviated CRC by ameliorating the intestinal barrier through the CLA-PPAR-γ axis. These results will promote the development of dietary probiotic supplements for CRC.

Conjugated Linoleic Acid Production in Pine Nut Oil: A Lactiplantibacillus plantarum Lp-01 Fermentation Approach.

Conjugated linoleic acid (CLA) is a class of bioactive fatty acids that exhibit various physiological activities such as anti-cancer, anti-atherosclerosis, and lipid-lowering. It is an essential fatty acid that cannot be synthesized by the human body and must be derived from dietary sources. The natural sources of CLA are limited, predominantly relying on chemical and enzymatic syntheses methods. Microbial biosynthesis represents an environmentally benign approach for CLA production. Pine nut oil, containing 40-60% linoleic acid, serves as a promising substrate for CLA enrichment. In the present study, we developed a novel method for the production of CLA from pine nut oil using Lactiplantibacillus plantarum (L. plantarum) Lp-01, which harbors a linoleic acid isomerase. The optimal fermentation parameters for CLA production were determined using a combination of single-factor and response surface methodologies: an inoculum size of 2%, a fermentation temperature of 36 °C, a fermentation time of 20 h, and a pine nut oil concentration of 11%. Under these optimized conditions, the resultant CLA yield was 33.47 µg/mL. Gas chromatography analysis revealed that the fermentation process yielded a mixture of c9, t11CLA and t10, c12 CLA isomers, representing 4.91% and 4.86% of the total fatty acid content, respectively.

Factors influencing conjugated linoleic acid content of dairy products: challenges and strategies.

Conjugated linoleic acid (CLA), a bioactive fatty acid that provides various physiological benefits, has gained increasing attention in the food industry, and various studies have focused on enhancing its content in dairy products. The factors influencing CLA content in dairy products vary significantly, including lactation stage, breed type, seasonality, feed, management methods of the animals, the manufacturing processes, storage, and ripening periods of the product. Additionally, the incorporation of CLA-producing probiotic bacteria, such as Lactobacillus, Lactococcus, Bifidobacterium, and Propionibacterium, is an emerging study in this field. Studies have revealed that factors affecting the CLA content in milk affect that in dairy products as well. Furthermore, the species and strains of CLA-producing bacteria, fermentation conditions, ripening period, and type of dairy product are also contributing factors. However, production of CLA-enhanced dairy products using CLA-producing bacteria while maintaining their optimal viability and maximizing exposure to free linoleic acid remains limited. The current review emphasized the factors affecting the CLA content and related mechanisms, challenges in the application of CLA-producing probiotic bacteria, and strategies to address these challenges and enhance CLA production in dairy products. Therefore, the development of functional dairy products with enhanced CLA levels is expected to be possible.

Growth performance, proximate composition and fatty acid profile of black soldier fly larvae reared on two grape pomace varieties.

The black soldier fly (Hermetia illucens) is attracting increasing interest for its ability to convert low-value substrates into highly nutritious feed. This study aimed at evaluating grape pomace from two varieties (Becuet - B; Moscato - M) as rearing substrates for black soldier fly larvae (BSFL), focusing on the related effects on larval growth performance, proximate composition, and fatty acid profile. A total of six replicates per treatment, and 1 000 BSFL per replica, were used. Larval development was assessed by larvae weight, which was recorded eight times during the trial: the day after the beginning of the trial, and then on days 5, 8, 13, 15, 20, 22, and 27 (day in which the 30% of BSFL reached the prepupal stage). Production and waste reduction efficiency parameters, namely the growth rate, substrate reduction and substrate reduction index, were calculated. The two grape pomace varieties were analysed for their proximate composition and fatty acid profile; the same analyses were conducted on BSFL (30 larvae per replica) that were collected at the end of the trial (day 27). The growth rate of BSFL showed a higher value when the larvae were reared on B substrate (4.4 and 3.2 mg/day for B and M, respectively; P < 0.01). The rearing substrate did not significantly affect the proximate composition of BSFL. The percentage of total lipids (TL) in M-fed BSFL was significantly higher than in B ones. Total saturated (P < 0.001) and monounsaturated fatty acids (P < 0.05) were significantly higher in M-fed BSFL, while an opposite trend was observed for total branched-chain (P < 0.001) and total polyunsaturated fatty acids (P < 0.001). Interestingly, some conjugated linoleic acid (CLA) isomers [i.e., C18:2 c9t11(+t7c9+t8c10) and t9t11] were detected in low amounts in both rearing substrates (total CLA equal to 0.085 and 0.16 g/100 g TL in B and M substrate, respectively). Some CLA isomers (i.e., C18:2 c9t11, t7c9, and t10c12) were also found in BSFL, reaching a total CLA concentration equal to 2.95 and 0.052 g/100 g of TL in B-fed and M-fed BSFL, respectively. This study demonstrates that winery by-products from different grape varieties can significantly affect the development and lipid composition of BSFL. The CLA biosynthesis potential of BSFL opens newsworthy perspectives for a new valorisation of winery by-products to produce full-fat black soldier fly meal and black soldier fly oil enriched in specific fatty acids of potential health-promoting interest.

Nutriomic Effects of Precision Lipids on Murine Hepatic Triacylglycerol Alterations Induced by High-Fat Diets.

INTRODUCTION: This study aims to investigate if a mixture of functional lipids (FLs), containing conjugated linoleic acid (CLA), tocopherols (TPs), and phytosterols (PSs), prevents some lipid alterations induced by high-fat (HF) diets, without adverse effects. METHODS: Male CF1 mice (n = 6/group) were fed (4 weeks) with control (C), HF, or HF + FL diets. RESULTS: FL prevented the overweight induced by the HF diet and reduced the adipose tissue (AT) weight, associated with lower energy efficiency. After the intervention period, the serum triacylglycerol (TAG) levels in both HF diets underwent a decrease associated with an enhanced LPL activity (mainly in muscle). The beneficial effect of the FL mixture on body weight gain and AT weight might be attributed to the decreased lipogenesis, denoted by the lower mRNA levels of SREBP1-c and ACC in AT, as well as by an exacerbated lipid catabolism, reflected by increased mRNA levels of PPARα, ATGL, HSL, and UCP2 in AT. Liver TAG levels were reduced in the HF + FL group due to an elevated lipid oxidation associated with a higher CPT-1 activity and mRNA levels of PPARα and CPT-1a. Moreover, genes linked to fatty acid biosynthesis (SREBP1-c and ACC) showed decreased mRNA levels in both HF diets, this finding being more pronounced in the HF + FL group. CONCLUSION: The administration of an FL mixture (CLA + TP + PS) prevented some lipid alterations induced by a HF diet, avoiding frequent deleterious effects of CLA in mice through the modulation of gene expression related to the regulation of lipid metabolism.

Conjugated linoleic acid (CLA) modulates bovine peripheral blood mononuclear cells (PBMC) proteome in vitro.

Conjugated linoleic acid (CLA) is a group of natural isomers of the n-6 polyunsaturated fatty acid (PUFA) linoleic acid, exerting biological effects on cow physiology. This study assessed the impact of the mixture 50:50 (vol:vol) of CLA isomers (cis-9, trans-11 and trans-10, cis-12) on bovine peripheral blood mononuclear cells (PBMC) proteome, identifying 1608 quantifiable proteins. A supervised multivariate statistical analysis, sparse variant partial least squares - discriminant analysis (sPLS-DA) for paired data identified 407 discriminant proteins (DP), allowing the clustering between the CLA and controls. The ProteINSIDE workflow found that DP with higher abundance in the CLA group included proteins related to innate immune defenses (PLIN2, CD36, C3, C4, and AGP), with antiapoptotic (SERPINF2 and ITIH4) and antioxidant effects (HMOX1). These results demonstrated that CLA modulates the bovine PBMC proteome, supports the antiapoptotic and immunomodulatory effects observed in previous in vitro studies on bovine PBMC, and suggests a cytoprotective role against oxidative stress. SIGNIFICANCE: In this study, we report for the first time that the mixture 50:50 (vol:vol) of cis-9, trans-11, and trans-10, cis-12-CLA isomers modulates the bovine PBMC proteome. Our results support the immunomodulatory and antiapoptotic effects observed in bovine PBMC in vitro. In addition, the present study proposes a cytoprotective role of CLA mixture against oxidative stress. We suggest a molecular signature of CLA treatment based on combining a multivariate sparse discriminant analysis and a clustering method. This demonstrates the great value of sPLS-DA as an alternative option to identify discriminant proteins with relevant biological significance.

Effect of coconut processing by-product graded feeding on carcass traits and meat quality of lambs.

The inclusion of by-product coconut mesocarp skins (CMS) in diets was evaluated in feedlot lambs. The objective of this study was to evaluate CMS levels effects on carcass traits and meat quality of lambs. Thirty-five male lambs with an initial body weight of 16.9 ± 2.93 kg were distributed in a completely randomized design with five CMS levels in total dry matter (0; 4.8; 9.6; 14.4 and 19.2%) and fed during 71 d until slaughter. High levels of CMS decreased the intake of dry matter and negatively affected the performance of lambs. Fat and protein contents of Longissimus lumborum muscle (P < 0.05) and the saturated fatty acid (FA) decreased (P < 0.001) whereas polyunsaturated FA increased (P < 0.01) with the inclusion of CMS. The ratio t10/t11-18:1 increased with the inclusion of CMS (P < 0.001). The instrumental color descriptors were unaffected by CMS levels. According to the effects on the investigated meat quality traits we recommend up to 4.8% CMS in diets of confined lambs.

Screening and Identification of High-Yielding Strains of Conjugated Linoleic Acid and Optimization of Conditions for the Conversion of CLA.

Conjugated linoleic acid (CLA) is a class of naturally occurring octadecadienoic acid in humans and animals and is a general term for a group of conformational and positional isomers of linoleic acid. In order to obtain the development of excellent lactic acid strains with a high production of conjugated linoleic acid, 32 strains with a possible CLA conversion ability were obtained by initial screening using UV spectrophotometry, and then the strains were re-screened by gas chromatography, and finally, the strain with the highest CLA content was obtained. The strains were optimized for cultivation by changing the amount of substrate addition, inoculum amount, and fermentation time. The results showed that the yield of the experimentally optimized strain for the conversion of conjugated linoleic acid could reach 94.68 ± 3.57 µg/mL, which was 74.4% higher than the initial yield of 54.28 ± 2.12 µg/mL of the strain. The results of this study can provide some basis for the application of conjugated linoleic acid production by Lactobacillus paracasei in the fermentation of lactic acid bacteria.

Transgenic female mice producing trans 10, cis 12-conjugated linoleic acid present excessive prostaglandin E2, adrenaline, corticosterone, glucagon, and FGF21.

Dietary trans 10, cis 12-conjugated linoleic acid (t10c12-CLA) is a potential candidate in anti-obesity trials. A transgenic mouse was previously successfully established to determine the anti-obesity properties of t10c12-CLA in male mice that could produce endogenous t10c12-CLA. To test whether there is a different impact of t10c12-CLA on lipid metabolism in both sexes, this study investigated the adiposity and metabolic profiles of female Pai mice that exhibited a dose-dependent expression of foreign Pai gene and a shift of t10c12-CLA content in tested tissues. Compared to their gender-match wild-type littermates, Pai mice had no fat reduction but exhibited enhanced lipolysis and thermogenesis by phosphorylated hormone-sensitive lipase and up-regulating uncoupling proteins in brown adipose tissue. Simultaneously, Pai mice showed hepatic steatosis and hypertriglyceridemia by decreasing gene expression involved in lipid and glucose metabolism. Further investigations revealed that t10c10-CLA induced excessive prostaglandin E2, adrenaline, corticosterone, glucagon and inflammatory factors in a dose-dependent manner, resulting in less heat release and oxygen consumption in Pai mice. Moreover, fibroblast growth factor 21 overproduction only in monoallelic Pai/wt mice indicates that it was sensitive to low doses of t10c12-CLA. These results suggest that chronic t10c12-CLA has system-wide effects on female health via synergistic actions of various hormones.

Biomolecular investigations into BBI reveal an enzymatic mechanism for PUFA isomerisation in bifidobacterium CFA bioconversion strains.

Multiple species of Bifidobacterium exhibit the ability to bioconvert conjugated fatty acids (CFAs), which is considered an important pathway for these strains to promote host health. However, there has been limited progress in understanding the enzymatic mechanism of CFA bioconversion by bifidobacteria, despite the increasing number of studies identifying CFA-producing strains. The protein responsible for polyunsaturated fatty acid (PUFA) isomerization in B. breve CCFM683 has recently been discovered and named BBI, providing a starting point for exploring Bifidobacterium isomerases (BIs). This study presents the sequence classification of membrane-bound isomerases from four common Bifidobacterium species that produce CFA. Heterologous expression, purification, and enzymatic studies of the typical sequences revealed that all possess a single c9, t11 isomer as the product and share common features in terms of enzymatic properties and catalytic kinetics. Using molecular docking and alanine scanning, Lys84, Tyr198, Asn202, and Leu245 located in the binding pocket were identified as critical to the catalytic activity, a finding further confirmed by site-directed mutagenesis-based screening assays. Overall, these findings provide insightful knowledge concerning the molecular mechanisms of BIs. This will open up additional opportunities for the use of bifidobacteria and CFAs in probiotic foods and precision nutrition.

Conjugated linoleic acid metabolite impact in colorectal cancer: a potential microbiome-based precision nutrition approach.

Colorectal cancer (CRC) is the second most deadly and the third most diagnosed cancer in both sexes worldwide. CRC pathogenesis is associated with risk factors such as genetics, alcohol, smoking, sedentariness, obesity, unbalanced diets, and gut microbiota dysbiosis. The gut microbiota is the microbial community living in symbiosis in the intestine, in a dynamic balance vital for health. Increasing evidence underscores the influence of specific gut microbiota bacterial species on CRC incidence and pathogenesis. In this regard, conjugated linoleic acid (CLA) metabolites produced by certain gut microbiota have demonstrated an anticarcinogenic effect in CRC, influencing pathways for inflammation, proliferation, and apoptosis. CLA production occurs naturally in the rumen, and human bioavailability is through the consumption of food derived from ruminants. In recent years, biotechnological attempts to increase CLA bioavailability in humans have been unfruitful. Therefore, the conversion of essential dietary linoleic acid to CLA metabolite by specific intestinal bacteria has become a promising process. This article reviews the evidence regarding CLA and CLA-producing bacteria as therapeutic agents against CRC and investigates the best strategy for increasing the yield and bioavailability of CLA. Given the potential and limitations of the present strategies, a new microbiome-based precision nutrition approach based on endogenous CLA production by human gut bacteria is proposed. A literature search in the PubMed and PubMed Central databases identified 794 papers on human gut bacteria associated with CLA production. Of these, 51 studies exploring association consistency were selected. After excluding 19 papers, due to health concerns or discrepancies between studies, 32 papers were selected for analysis, encompassing data for 38 CLA-producing bacteria, such as Bifidobacterium and Lactobacillus species. The information was analyzed by a bioinformatics food recommendation system patented by our research group, Phymofood (EP22382095). This paper presents a new microbiome-based precision nutrition approach targeting CLA-producing gut bacterial species to maximize the anticarcinogenic effect of CLA in CRC.

Trans 10, cis 12-conjugated linoleic acid reduced reproductive ability by disrupting the estrus cycle in female mice.

As a positional and geometrical isomer of linoleic acid, trans 10, cis 12 conjugated linoleic acid (t10c12-CLA) reduces white fat by reducing food intake, modulating lipid metabolism, and stimulating energy expenditure. However, the t10c12-CLA products are mostly mixtures, making it difficult to obtain accurate results. Studies are needed to investigate the effects of pure t10c12-CLA on animals and humans. In this study, we used the biallelic transgenic (tg) mice, which could produce t10c12-CLA itself, to investigate the effects of pure t10c12-CLA on female reproductive ability. The results showed that the body and relative ovary weights had no significant difference between tg and wild-type (wt) littermates at ages 3 or 10 weeks. While the fecundity test found that tg mice had a significantly longer first litter time (32.0 ± 4.70 days vs. 21.3 ± 2.31 days, P<0.05), and a significantly lower number of litters (4.75 ± 2.75 vs. 6.67 ± 0.57, P<0.05) when compared with wt mice during continuous mating within seven months. Hormone profiles showed that serum estradiol levels did not change in tg mice; however, significantly (P<0.05) decreased progesterone and increased prostaglandin E2 levels were observed in tg mice compared with those of wt mice. Hematoxylin-eosin staining showed no pathological characteristics in tg ovaries, except for the increased atresia follicles (P<0.05). Moreover, the tg mice had a significantly more extended diestrus period than the wt mice (48.4 ± 6.38% vs. 39.6 ± 3.81%, P<0.05). In summary, t10c12-CLA could affect serum progesterone and prostaglandin E2 levels, lead to a disordered estrus cycle, and impact the reproductive performance of female mice. This study provided theoretical and biosafety recommendations for applying t10c12-CLA in female mammals.

Conjugated Linoleic Acid Ameliorates High Fat-Induced Insulin Resistance via Regulating Gut Microbiota-Host Metabolic and Immunomodulatory Interactions.

Interaction between gut microbiota, host immunity and metabolism has been suggested to crucially affect the development of insulin resistance (IR). This study aims to investigate how gut microbiota, inflammatory responses and metabolism in individuals with IR are affected by the supplementation of conjugated linoleic acid (CLA) and how this subsequently affects the pathophysiology of IR by using a high-fat diet-induced IR mouse model. Serum biochemical indices showed that 400 mg/kg body weight of CLA effectively attenuated hyperglycemia, hyperlipidemia, glucose intolerance and IR, while also promoting antioxidant capacities. Histomorphology, gene and protein expression analysis revealed that CLA reduced fat deposition and inflammation, and enhanced fatty acid oxidation, insulin signaling and glucose transport in adipose tissue or liver. Hepatic transcriptome analysis confirmed that CLA inhibited inflammatory signaling pathways and promoted insulin, PI3K-Akt and AMPK signaling pathways, as well as linoleic acid, arachidonic acid, arginine and proline metabolism. Gut microbiome analysis further revealed that these effects were highly associated with the enriched bacteria that showed positive correlation with the production of short-chain fatty acids (SCFAs), as well as the improved SCFAs production simultaneously. This study highlights the therapeutic actions of CLA on ameliorating IR via regulating microbiota-host metabolic and immunomodulatory interactions, which have important implications for IR control.

Levels of lipid-derived gut microbial metabolites differ among plant matrices in an in vitro model of colon fermentation.

This study explored differences in microbial lipid metabolites among sunflower seeds, soybeans, and walnuts. The matrices were subjected to in vitro digestion and colonic fermentation. Defatted digested materials and fiber/phenolics extracted therefrom were added to sunflower oil (SO) and also fermented. Targeted and untargeted lipidomics were employed to monitor and tentatively identify linoleic acid (LA) metabolites. Walnut fermentation produced the highest free fatty acids (FFAs), LA, and conjugated LAs (CLAs). Defatted digested walnuts added to SO boosted FFAs and CLAs production; the addition of fibre boosted CLAs, whereas the addition of phenolics only increased 9e,11z-CLA and 10e,12z-CLA. Several di-/tri-hydroxy-C18-FAs, reported as microbial LA metabolites for the first time, were annotated. Permutational multivariate analysis of variance indicated significant impacts of food matrix presence and type on lipidomics and C18-FAs. Our findings highlight how the food matrices affect CLA production from dietary lipids, emphasizing the role of food context in microbial lipid metabolism.

Dietary supplementation of phytoncide and soybean oil increases milk conjugated linoleic acid and depresses methane emissions in Holstein dairy cows.

The objective of this study was to determine whether adding phytoncide oil (PO) and soybean oil (SBO) to the dairy cow diet could increase milk conjugated linoleic acid (CLA) and depress methane (CH4) emissions in Holstein dairy cows. Rumen fermentation was conducted at four levels of SBO (0, 1, 2, and 4%, on DM basis) and two levels of PO (0 and 0.1%, on DM basis) with in vitro experiment. To evaluate blood parameters, fecal microbe population, milk yield and fatty acid compositions, and CH4 production, in vivo experiment was conducted using 38 Holstein dairy cows divided into two groups of control (fed TMR) and treatment (fed TMR with 0.1% PO and 2% SBO as DM basis). In the in vitro study (Experiment 1), PO or SBO did not affect rumen pH. However, SBO tended to decrease ruminal ammonia-N (p = 0.099). Additionally, PO or SBO significantly decreased total gas production (p = 0.041 and p = 0.034, respectively). Both PO and SBO significantly decreased CH4 production (p < 0.05). In addition, PO significantly increased both CLA isomers (c9, t11 and t10, c12 CLA) (p < 0.001). Collectively, 0.1% PO and 2% SBO were selected resulting in most effectively improved CLA and decreased CH4 production. In the in vivo study (Experiment 2), 0.1% PO with 2% SBO (PSO) did not affect complete blood count. However, it decreased blood urea nitrogen and magnesium levels in blood (p = 0.021 and p = 0.01, respectively). PSO treatment decreased pathogenic microbes (p < 0.05). It increased milk yield (p = 0.017) but decreased percentage of milk fat (p = 0.013) and MUN level (p < 0.01). In addition, PSO treatment increased both the concentration of CLA and PUFA in milk fat (p < 0.01). Finally, it decreased CH4 emissions from dairy cows. These results provide compelling evidence that a diet supplemented with PSO can simultaneously increase CLA concentration and decrease CH4 production with no influence on the amount of milk fat (kg/day) in Holstein dairy cows.

Conjugated Linolenic Acid (CLnA) vs Conjugated Linoleic Acid (CLA): A Comprehensive Review of Potential Advantages in Molecular Characteristics, Health Benefits, and Production Techniques.

Conjugated linoleic acid (CLA) has been extensively characterized due to its many biological activities and health benefits, but conjugated linolenic acid (CLnA) is still not well understood. However, CLnA has shown to be more effective than CLA as a potential functional food ingredient. Current research has not thoroughly investigated the differences and advantages between CLnA and CLA. This article compares CLnA and CLA based on molecular characteristics, including structural, chemical, and metabolic characteristics. Then, the in vivo research evidence of CLnA on various health benefits is comprehensively reviewed and compared with CLA in terms of effectiveness and mechanism. Furthermore, the potential of CLnA in production technology and product protection is analyzed. In general, CLnA and CLA have similar physicochemical properties of conjugated molecules and share many similarities in regulation effects and pathways of various health benefits as well as in the production methods. However, their specific properties, regulatory capabilities, and unique mechanisms are different. The superior potential of CLnA must be specified according to the practical application patterns of isomers. Future research should focus more on the advantageous characteristics of different isomers, especially the effectiveness and safety in clinical applications in order to truly exert the potential value of CLnA.

Conjugated linoleic acid (CLA) reduces HFD-induced obesity by enhancing BAT thermogenesis and iWAT browning via the CD36-AMPK pathway.

The antiobesity effect of conjugated linoleic acid (CLA) has been reported. However, the underlying mechanisms have not been fully clarified. Thus, this study aimed to investigate the effects of CLA on thermogenesis of interscapular brown adipose tissue (iBAT) and browning of inguinal subcutaneous white adipose tissue (iWAT) and explore the possible signaling pathway. The in vivo results showed that CLA enhanced the O2 consumption and heat production in HFD (high-fat diet)-fed female mice by roughly 38%. Meanwhile, CLA increased the average iBAT temperature by 2°C at the room temperature and cold exposure, respectively. Correspondingly, CLA caused 1.6- and 2.4-fold increases in the expression of UCP1 (uncoupling protein 1) of BAT and iWAT, respectively, suggesting the activated iBAT thermogenesis and iWAT browning in HFD-fed female mice. Meanwhile, CLA could promote the formation of brown and beige adipocytes in differentiated stromal vascular cells (SVCs) isolated from iBAT and iWAT (the expressions of UCP1 were promoted by about twofold changes). In possible mechanisms, CLA stimulated the expression of CD36 and the activation of the AMPK pathway in mice iBAT and iWAT as well as the differentiated SVCs. However, inhibition of CD36 and AMPK (adenosine 5'-monophosphate-activated protein kinase) abolished the promotive effects of CLA on brown and beige adipocytes formation. Hence, we showed that CLA reduced HFD-induced obesity through enhancing iBAT thermogenesis and iWAT browning via the  CD36-AMPK pathway.