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Virgin coconut oil (VCO) is the most oldest edible oil, extracted from fresh and mature kernel using wet or dry methods, therefor the resulting oil is a pure, clear, and colorless with a scent of fresh coconut, these characteristics make VCO has the preferableness in medical and health applications, over refining coconut oil (RCO) that is extract from kernel of coconut after drying by methods makes the oil refining, bleaching and deodorizing. In spite of that, the chemical compositions particularly the fatty acids in both VCO and RCO are the same with no significant difference. MCFAs which are classified as MCTs, are the basic components in both VCO and RCO, these MCFAs particularly lauric acid (LA) following by capric and caprylic acids playing a great role in antimicrobial activity of coconut oil, therefor the extraction of these fatty acids are show more antibacterial activity on pathogenic bacteria more than lipolyzed VCO or VCO itself that may not show inhibition effect. Gram positive bacteria is more sensitive than gram negative one towards LA and other fatty acids, therefor these fatty acids at high concentrations showed inhibition effect on gram negative bacteria, while at low concentration showed resistance. This study attempts to review the chemical components in both VCO and RCO based on their extraction methods, also the antibacterial activity and the mechanism of action, also suggests that RCO has the same effect as antibacterial as VCO based on their chemical compositions. [ABSTRACT FROM AUTHOR]

Copyright of Avian Diseases is the property of American Association of Avian Pathologists, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Medium chain fatty acids are candidates of partial sulphur dioxide replacement in wine, as a solution to the growing consumer concerns about chemical additives. In botrytised sweet wine specialties, large amount of sulphur dioxide addition is one of the effective practices to stop alcoholic fermentation. Increasing medium chain fatty acid levels up to 80 mg l-1 was tested as a sole inhibitor on solid agar surface. S. bacillaris seemed to be the most sensitive, S. cerevsisiae and S. bayanus were more tolerant, while Z. bailii showed the highest tolerance. Then, increasing medium chain fatty acid levels up to 40 mg l-1 combined with 100 mg l-1 sulphur dioxide was introduced into a Tokaj Essence under refermentation. After 56 days, the highest dosage had pronounced effect on the yeast population, but the refermentation was not inhibited completely. Medium chain fatty acids have varying inhibitory effect on botrytised wine-related yeasts, moreover, it could be used effectively in media with high ethanol content, unlike Tokaj Essence. [ABSTRACT FROM AUTHOR]

• The bioconversion of swine manure into MCCA was investigated. • Initial fermentation pH of 10.0 can enhance SCFAs production from swine manure. • Around 61.3% of the consumed SCFA was used to synthesize MCFA. • A higher concentration of n -heptanoate was achieved than past studies using other feedstock. This research proposes and demonstrates, for the first time, the utilization of swine manure as a complex feedstock to produce high-value medium chain fatty acids (MCFA). The two-stage anaerobic digestion (AD) carboxylates platform was adopted for the conversion of swine manure to short chain fatty acids (SCFAs) and then SCFAs to MCFA (n- caproate, n- heptanoate, and n- caprylate) with ethanol supplementation. We defined the appropriate initial pH of 10.0 for SCFAs production with a carbon conversion rate of 71.2%, and acetate, propionate were the main products, which accounted for around 72.9% of the total SCFAs in the primary stage (I). Through the addition of ethanol, 61.3% of the converted carbon in the complex SCFAs solution was converted into MCFA (C6-C8) in the chain elongation stage (II), while only 6.7% was attributed to methane formation. The concentrations of n -caproate, n -heptanoate, and n -caprylate reached 8.6 g COD/L (3.9 g/L), 6.4 g COD/L (2.7 g/L), and 2.6 g COD/L (1.07 g/L), respectively. This study achieved a relatively higher concentration of n -heptanoate compared with past studies of MCFA from other feedstock. These findings demonstrated a new route for resource recovery and the operating parameters for producing MCFA from swine manure. [ABSTRACT FROM AUTHOR]

Background: We hypothesized that supplementation of nursery and grower pig diets with coconut oil in the absence of antibiotics would yield maintenance of glucose homeostasis, growth performance, and immune function similar to what is achieved with nursery and grower pig diets containing antibiotics. Pigs received the same base treatment diets from d24 (weaning) to d71 of age and had blood and fecal samples collected on d24, d31, d45 and d71 for measurement of whole blood glucose, serum insulin, cortisol and cytokines, and fecal microbiome. Pigs had weekly weights and daily feed consumption measured throughout the study. Animals were euthanized at d71 and subcutaneous fat and ileal contents were collected for assessment for fatty acids and microbiome, respectively. Diet treatments consisted of 2% soybean oil plus antibiotics (ABX; n = 22), 2% soybean oil without antibiotics (NABX; n = 22), and 2% coconut oil without antibiotics (COC; n = 22). Statistical analysis examined the effect of diet within each timepoint using a repeated measures ANOVA. Results: Pigs fed COC diet had decreased serum insulin levels, maintained feed intake, feed conversion and weight gain, and, based on serum cytokines and fecal microbiome, were immunologically similar to ABX-fed pigs. However, NABX-fed pigs performed similarly to the ABX-fed pigs in all parameters except for serum cytokines. Additionally, there was no difference in the incidence of diarrhea between any of the diet treatments. Conclusions: This study demonstrates that dietary antibiotics are not necessary to maintain growth performance in nursery and grower pigs. However, dietary antibiotics appear to modulate circulating cytokine levels. Dietary coconut oil is neither harmful nor helpful to growth performance or immune function in nursery and grower pigs but does modulate serum insulin levels. Therefore, while coconut oil fed at 2% by weight is a suitable substitute for dietary antibiotics, this study suggests that no substitute for dietary antibiotics is needed at all. [ABSTRACT FROM AUTHOR]

Antibiotics have great functions in farm animal. However, the harm of antibiotics can't be ignored. The effects of medium‐chain fatty acids (MCFAs) supplementation to basal diet instead of antibiotics (CSP, Chlortetracycline, sulphonamide dimethazine and procaine penicillin, 1:1:1) on growth performance, nutrient digestibility and blood profile in growing pigs were studied. A total of 140 growing pigs (Landrace × Yorkshire × Duroc) with an average body weight of 27.84 ± 0.42 kg were allotted to four treatments of seven replicates/treatment and five pigs/replicate. The four experimental diets included: CON (basal diet, non‐antibiotic, negative control); CSP (CON + CSP 0.1%, positive control); M1 (CON + MCFA 0.15%) and M2 (CON + MCFA 0.3%). After 5 weeks, the fresh faecal and blood samples were collected from rectum and jugular vein respectively. The average daily gain (ADG) was significantly improved for pigs fed 0.3% MCFAs in relation to basal diet. Meanwhile, CSP supplementation had comparable effect on ADG. The lymphocyte percentage and IgG concentration were higher in blood of pigs‐fed MCFAs in relation to that of CON and CSP treatment while white blood cell and red blood cell were not affected. In relation to basal diet and CSP treatment, the digestibility of dry matter, nitrogen and gross energy (E) were unaffected with MCFAs supplementation. In conclusion, MCFAs improved growth performance on body weight gain and immune profile. Addition 0.3% MCFAs into the diet indicated that its partial positive effect as an alternative to antibiotic. [ABSTRACT FROM AUTHOR]

Palm oil mill effluent (POME) was dark fermented into biohydrogen for clean energy production with volatile fatty acids (VFAs) as a byproduct. The VFAs remaining 70% in hydrogenic POME offer potential substrate for conversion into valuable medium-chain fatty acids (MCFA), presenting an opportunity for resource recovery and environmental mitigation. This study investigated the influence of varying operating parameters on continuous MCFA production from biohydrogenic POME through a stirred tank reactor. Optimizing MCFA production necessitates a 5.4 g/L ethanol load supplemented with 2.6 g/L NaHCO 3 and 1.5 L-CO 2 /L/d while maintaining a pH of 6.5 and a temperature of 35 °C. Under optimized conditions, a maximum MCFA production of 2.2 g-COD/L was achieved, consisting primarily of 1.8 g-COD/L caproic acid, 0.2 g-COD/L heptanoic acid, and 0.2 g-COD/L caprylic acid, translating to a total MCFA yield of 0.5 g-COD/g-COD and MCFA selectivity of 51% with Caproiciproducens sp. (45%), Lactobacillus sp. (21%), and Clostridium sp. (14%) as predominant bacteria. Notably, CO 2 loading significantly enhances MCFA production, particularly caproic and heptanoic acids. Remarkably, the system maintained stable MCFA production for an impressive 220 days. The microbial community in the reactor effectively removed total solids, volatile solids, chemical oxygen demand (COD), suspended solids of 42%, 61%, 31%, and 95%, respectively. Key bacteria like Caproiciproducens sp., C. kluyveri , Clostridium sp., and Sporanaerobacter sp. possess most of the enzymes required for the reverse β-oxidation pathway, an energy-efficient pathway for MCFA generation. This study makes a significant contribution to the field of biowaste valorization, specifically focusing on anaerobic fermentation for bio-based chemical production. Despite challenges related to butyric acid accumulation and inhibition, these findings offer promising potential for scaling up the fermentation process. [Display omitted] • High MCFA production and solid reduction from biohydrogenic POME was achieved. • The addition of ethanol, NaHCO 3 , and CO 2 enhanced MCFA production. • Caproiciproducens sp. is a key bacterium in chain elongation. • Caproiciproducens, Lactobacillus, and Clostridium were dominant microbial species. • MCFA production of 2.2 g-COD/L and a solid reduction of 95% was achieved. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Chinese Society of Animal Science is the property of Chinese Society of Animal Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fatty acids are derived from diet and fermentative processes by the intestinal flora. Two to five carbon chain fatty acids, termed short chain fatty acids (SCFA) are increasingly recognized to play a role in intestinal homeostasis. However, the characteristics of slightly longer 6 to 10 carbon, medium chain fatty acids (MCFA), derived primarily from diet, are less understood. Here, we demonstrated that SCFA and MCFA have divergent immunomodulatory propensities. SCFA down-attenuated host pro-inflammatory IL-1β, IL-6, and TNFα response predominantly through the TLR4 pathway, whereas MCFA augmented inflammation through TLR2. Butyric (C4) and decanoic (C10) acid displayed most potent modulatory effects within the SCFA and MCFA, respectively. Reduction in TRAF3, IRF3 and TRAF6 expression were observed with butyric acid. Decanoic acid induced up-regulation of GPR84 and PPARγ and altered HIF-1α/HIF-2α ratio. These variant immune characteristics of the fatty acids which differ by just several carbon atoms may be attributable to their origins, with SCFA being primarily endogenous and playing a physiological role, and MCFA exogenously from the diet.

In a circular economy strategy, waste resources can be used for the biological production of high added-value substances, such as medium chain fatty acids (MCFAs), thus minimising waste and favouring a sustainable process. This study investigates single-stage fermentation processes for the production of MCFAs in a semi-continuous reactor treating the extract of real food waste (FW), without the addition of external electron donors. Two sequential acidogenic fermentation tests were carried out at an organic loading rate (OLR) of 5 and 15 gCOD L−1d−1 with a hydraulic retention time of 4 days and pH controlled at 6 ± 0.2. The highest level of caproate (4.8 g L−1) was observed at OLR of 15 gCOD L−1d−1 with a microbiome mainly composed by lactate-producing Actinomyces, Atopobium, and Olsenella species and caproate-producing Pseudoramibacter. Metagenomic analysis revealed the presence of key enzymes for the production of lactate, such as lactate dehydrogenase and pyruvate ferredoxin oxidoreductase, as well as several enzymes involved in the reverse β-oxidation pathway, thus suggesting the occurrence of a lactate-based chain elongation process.

Clostridium kluyveri was used for chain elongation of C2 C4 fatty acids in stirred tank bioreactors. The influence of different electron acceptors (acetic acid, butyric acid and the mixture of both) on C6 fatty acid production was evaluated in presence of ethanol using similar molar alcohol/acid ratios around 3.5. Bottle batch assays without pH regulation and with only acetic acid as electron acceptor yielded a final C6 fatty acid concentration of 6.8 ± 0.6 g L−1. Then, pH-regulated bioreactors were operated at constant pH of 6.8. Under such conditions, the maximum growth rate was 0.039 h−1 obtained using acetic acid and butyric acid as electron acceptors, whereas the lowest growth rate was 0.010 h−1 with only butyric acid as electron acceptor. The maximum growth rate with acetic acid only, was similar, though slightly lower, as with the mixture of C2 C4 fatty acids. Besides, the maximum productions of hexanoic acid were 11.8 g L−1, 13.1 g L−1 and 21.2 g L−1 using, respectively, acetic acid, butyric acid and the mixture of both acids as electron acceptors. Thus, the use of a mixture of acetic acid and butyric acid in presence of ethanol for chain elongation, at constant pH, proved to be efficient for hexanoic acid production. • C. kluyveri was proven to be able to produce unusually high amount of hexanoic acid. • Maintaining a constant pH of 6.8 enhances hexanoic acid production by C. kluyveri. • C. kluyveri grows better with a mixture of ethanol and acetic and butyric acids. • Ethanol, acetic and butyric acids yielded as much as 21.2 g L−1 hexanoic acid. [ABSTRACT FROM AUTHOR]

Background: Enterococcus faecalis and Candida albicans are the microbes that are most resistant to elimination by disinfecting agents and are the causative agents for reinfection of the root canal treated teeth. Medium chain fatty acids (MCFAs), which are the main components of coconut oil, are proven antimicrobial agents. Thus, the aim of this study was to evaluate their antimicrobial efficacy against E. faecalis and C. albicans.Methodology: Ninety extracted single-rooted mandibular premolar teeth were decoronated, biomechanically prepared, autoclaved, and divided into three groups (n = 30): Group A (inoculated with E. faecalis), Group B (inoculated with C. albicans), and Group C (control group). Each group was again subdivided into three groups (n = 10) and irrigated with lauric acid (LA), decanoic acid (DA), and octanoic acid, respectively, for 5 min. Paper point samples were taken from canal walls and transferred into Brain Heart Infusion broth and potato dextrose broth and placed in an incubator at 37°C. The appearance of tubidity was checked at 24, 48, 72, and 96 h using direct contact test. The data were then statistically analyzed using the analysis of variance and Tukey honestly significant difference post hoc tests.Results: Among the three MCFAs, LA showed the maximum inhibitory against E. faecalis at 24 h and the inhibitory activity decreased considerably at 48, 72, and 96 h. DA was the most effective against C. albicans with a maximum inhibition at 48 h. DA also showed significant substantivity at 72 and 96 h.Conclusion: Within the limitations of this study, it can be concluded that MCFAs show promising antimicrobial efficacy against E. faecalis and C. albicans. [ABSTRACT FROM AUTHOR]

Summary: Partially defatted coconut flour (PDCF) as a source of medium chain fatty acids was selected to replace fat in rusk formulation. Effect of replacement of wheat flour with PDCF (10%, 20% and 30%) on quality characteristics of rusk was studied. Increasing PDCF from 0% to 30% decreased farinograph water absorption, amylograph peak viscosity and overall quality score (52.5 to 19.5) of rusk. Use of additive mix, AM (4% dry gluten powder + 0.002% fungal α‐amylase) to 20% PDCF, increased the farinograph dough stability, strength of the paste during heating and overall quality score (39.5 to 50.5). The rusk with 20% PDCF + AM was stable up to 30 days, had 1.6, 5.5 times higher protein and dietary fibre contents as compared to control rusk respectively. The fat in the rusk had zero trans fatty acids and contained 66.2% medium chain fatty acids with lauric acid as a major fatty acid. [ABSTRACT FROM AUTHOR]

Highlights • A screening method based on gene overexpression was developed. • The efflux and influx transporters for MCFA were identified. • Efficient efflux pump system was constructed for MCFA. Abstract Medium-chain fatty acids (C 6 -C 10 , MCFAs) represent valuable molecules for food and pharmaceutical industries. However, MCFAs in Escherichia coli induce stresses and toxicity, reducing final yields. These phenotypes could be alleviated if MCFA export from cells was accelerated, yet information on proteins responsible for exporting MCFAs remains limited. Here, a panel of 17 genes or operons was screened. Overexpressing resistance nodulation cell division family transporter acrE , mdtE and mdtC increased MCFA titer by 46.4%, 65.2% and 33.8%, whereas overexpressing transcriptional activators soxS , marA and multidrug efflux pumps cmr , fadL decreased MCFA titer by 42.5%, 27.8%, 37.6% and 29.5%, respectively. Furthermore, the effect of multiple transporter engineering was investigated. Overexpressing acrE , mdtE and mdtC together with deleting cmr increased MCFA production by more than two-fold. This study demonstrated the efficient efflux pump specifically for MCFAs and this multiple transporter engineering strategy can be employed to synthesize other bio-products toxic to microorganisms. [ABSTRACT FROM AUTHOR]

[Display omitted] • MCFAs production from AFRs via two-stage anaerobic fermentation was performed. • Effect of radiation pretreatment on fate of ARGs and MCFA production was explored. • Radiation at 10–50 kGy decreased ARGs abundance by 0.6–21.1% at end of fermentation. • Radiation pretreatment of AFRs promoted the MCFA production. The propagation of antibiotic resistance genes (ARGs) restricts the application of antibiotic fermentation residues (AFRs). This study investigated medium chain fatty acids (MCFA) production from AFRs, focusing on the effect of ionizing radiation pretreatment on the fates of ARGs. The results indicated that ionizing radiation pretreatment not only stimulated the MCFA production, but also inhibited the proliferation of ARGs. Radiation at 10–50 kGy decreased ARGs abundances by 0.6–21.1% at the end of fermentation process. Mobile genetic elements (MGEs) exhibited higher resistance to ionizing radiation, radiation over 30 kGy was required to suppress the proliferation of MGEs. Radiation at 50 kGy achieved an adequate inhibition to MGEs, and the degradation efficiency was 17.8–74.5% for different kinds of MGEs. This work suggested that ionizing radiation pretreatment could be a good option to ensure the safer application of AFRs by eliminating the ARGs and preventing the horizontal gene transfer of ARGs. [ABSTRACT FROM AUTHOR]

Delayed feed and water access is known to impair growth performance of day old broiler chickens. Although effects of feed access on growth performance and immune function of broilers have been examined before, effects of dietary composition and its potential interaction with feed access are hardly investigated. This experiment aimed to determine whether moment of first feed and water access after hatch and pre-starter composition (0 to 7 days) affect growth rate and humoral immune function in broiler chickens. Direct fed chickens received feed and water directly after placement in the grow-out facility, whilst delayed fed chickens only after 48 h. Direct and delayed fed chickens received a control pre-starter diet, or a diet containing medium chain fatty acids (MCFA) or fish oil. At 21 days, chickens were immunized by injection of sheep red blood cells. The mortality rate depended on an interaction between feed access and pre-starter composition (P=0.014). Chickens with direct feed access fed the control pre-starter diet had a higher risk for mortality than chickens with delayed feed access fed the control pre-starter diet (16.4% v. 4.2%) whereas the other treatment groups were in-between. BW gain and feed intake till 25 days in direct fed chickens were higher compared with delayed fed chickens, whilst gain to feed ratio was lower. Within the direct fed chickens, the control pre-starter diet resulted in the highest BW at 28 days and the MCFA pre-starter diet the lowest (Δ=2.4%), whereas this was opposite for delayed fed chickens (Δ=3.0%; P=0.033). Provision of MCFA resulted in a 4.6% higher BW gain and a higher gain to feed ratio compared with other pre-starter diets, but only during the period it was provided (2 to 7 days). Minor treatment effects were found for humoral immune response by measuring immunoglobulins, agglutination titers, interferon gamma (IFN-γ), and complement activity. Concluding, current inclusion levels of fish oil (5 g/kg) and MCFA (30 g/kg) in the pre-starter diet appear to have limited (carryover) effects on growth and development, as well as on humoral immune function.

The bioaccessibility and activity of polyphenols is dependent on their structure and entrapment in the food matrix. While dietary lipids are known to transit into the colon, the impact of different lipids on the microbiome, and their interactions with dietary polyphenols are largely unknown. Here, we investigated the effect of dietary lipids on the bioaccessibility of polyphenols from purple/black carrots and adaptation of the gut microbiome in a simulated in vitro digestion-fermentation. Coconut oil, sunflower oil, and beef tallow were selected to represent common dietary sources of medium-chain fatty acids (MCFAs), long-chain polyunsaturated fatty acids (PUFAs), and long-chain polysaturated fatty acids (SFAs), respectively. All lipids promoted the bioaccessibility of both anthocyanins and phenolic acids during intestinal digestion with coconut oil exhibiting the greatest protection of anthocyanins. Similar trends were shown in antioxidant assays (2,2-Diphenyl-1-pricrylhydrazyl (DPPH), ferric reducing ability (FRAP), and total phenolic content (TPC)) with higher phytochemical bioactivities observed with the addition of dietary lipids. Most bioactive polyphenols were decomposed during colonic fermentation. Black carrot modulated diversity and composition of a simulated gut microbiome. Dramatic shifts in gut microbiome were caused by coconut oil. Inclusion of sunflower oil improved the production of butyrate, potentially due to the presence of PUFAs. The results show that the impact of polyphenols in the digestive tract should be considered in the context of other components of the diet, particularly lipids.

The objective of the present study was to evaluate the effect of oils for sows during late pregnancy and lactation on offspring performance. In addition, the effect of caprylic acid (C8) or medium-chain triglyceride oil (MCT) in piglets’ feed on their gut development, performance, and health status was determined. The experiment was conducted on 24 sows allocated to two treatments: diet with rapeseed oil or with coconut oil. Newborn piglets were randomly allocated to three treatments: feed with no supplement or supplemented with 0.3% MCT or with 0.3% C8. The results showed that both oils had no effect on sow reproductive rates; however, fatty acid patterns of milk differed significantly and the number of lost piglets was lower in sow fed with coconut oil. Both caprylic and MCT oil significantly improved piglet performance and villus height. These additives did not change triacylglycerol content in blood, but C8 lowered total cholesterol and MCT increased IgG content. It can be concluded that coconut oil fed to pregnant and lactating sows can markedly reduce the mortality of piglets and that caprylic acid and medium-chain fatty acid oil can be a good supplement in weaned piglet feed.

There is mounting evidence that oxidative glucose metabolism is impaired in epilepsy and recent work has further characterized the metabolic mechanisms involved. In healthy people eating a traditional diet, including carbohydrates, fats and protein, the major energy substrate in brain is glucose. Cytosolic glucose metabolism generates small amounts of energy, but oxidative glucose metabolism in the mitochondria generates most ATP, in addition to biosynthetic precursors in cells. Energy is crucial for the brain to signal “normally,” while loss of energy can contribute to seizure generation by destabilizing membrane potentials and signaling in the chronic epileptic brain. Here we summarize the known biochemical mechanisms that contribute to the disturbance in oxidative glucose metabolism in epilepsy, including decreases in glucose transport, reduced activity of particular steps in the oxidative metabolism of glucose such as pyruvate dehydrogenase activity, and increased anaplerotic need. This knowledge justifies the use of alternative brain fuels as sources of energy, such as ketones, TCA cycle intermediates and precursors as well as even medium chain fatty acids and triheptanoin.

Colorectal cancer, breast cancer and skin cancer are commonly-reported cancer types in the U.S. Although radiation and chemotherapy are routinely used to treat cancer, they produce side effects in patients. Additionally, resistance to chemotherapeutic drugs has been noticed in cancers. Thus, there is a need for effective and safe bioprophylactics and biotherapeutics in cancer therapy. The medicinal value of goat milk has been recognized for centuries and is primarily attributed to three fatty acids, namely capric, caprylic and caproic acids. This research investigates the anticancer property of these fatty acids on human colorectal, skin and mammary gland cancer cells. The cancer cells were treated with various concentrations of fatty acids for 48 h, and cell viability was monitored by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay. Additionally, real-time quantitative PCR (RT-qPCR) was performed to elucidate the potential anti-cancer mechanisms of the three fatty acids under investigation. Capric, caprylic and caproic acids reduced cancer cell viability by 70% to 90% (p < 0.05) compared to controls. RT-qPCR data indicated that these natural molecules produced anticancer effects by down-regulating cell cycle regulatory genes and up-regulating genes involved in apoptosis. Future research will validate the anticancer effect of these fatty acids in an appropriate in vivo model.

There is mounting evidence that oxidative glucose metabolism is impaired in epilepsy and recent work has further characterized the metabolic mechanisms involved. In healthy people eating a traditional diet, including carbohydrates, fats and protein, the major energy substrate in brain is glucose. Cytosolic glucose metabolism generates small amounts of energy, but oxidative glucose metabolism in the mitochondria generates most ATP, in addition to biosynthetic precursors in cells. Energy is crucial for the brain to signal “normally,” while loss of energy can contribute to seizure generation by destabilizing membrane potentials and signaling in the chronic epileptic brain. Here we summarize the known biochemical mechanisms that contribute to the disturbance in oxidative glucose metabolism in epilepsy, including decreases in glucose transport, reduced activity of particular steps in the oxidative metabolism of glucose such as pyruvate dehydrogenase activity, and increased anaplerotic need. This knowledge justifies the use of alternative brain fuels as sources of energy, such as ketones, TCA cycle intermediates and precursors as well as even medium chain fatty acids and triheptanoin. [ABSTRACT FROM AUTHOR]

Microorganisms are responsible for biochemical cycles and therefore play essential roles in the environment. By using omics approaches and network analysis to understand the interaction and cooperation within mixed microbial communities, it would be possible to engineer microbiomes in fermentation and digestion reactors to convert organic waste into valuable products. [ABSTRACT FROM AUTHOR]

Impaired epithelial barrier function disrupts immune homeostasis and increases inflammation in intestines, leading to many intestinal diseases. The blend of organic acids (OAs) and medium chain fatty acids (MCFAs) has been shown to have synergistic bactericidal effect. In this study, we demonstrated that two blends of OAs and MCFAs (OM1 and OM2) could prevent the inflammatory response and intestinal barrier dysfunction in enterohemorrhagic Escherichia coli (EHEC)-infected mice. Treatments of OM1 and OM2 significantly reduced the body weight loss and production of IL-6 and TNF-α induced by EHEC. Mice treated with OM1 and OM2 showed decrease in serum D-lactic concentration, DAO activity and bacterial transfer to liver and spleen. Furthermore, OM1 and OM2 increased the expression of tight junction proteins occludin and ZO-1, mucus protein MUC-2, and host defense peptides mBD1, mBD2 and mBD3. Finally, OM1 and OM2 increased the population of Lactobacillus spp. and Bifidobacterium spp., but decreased that of E. coli in the cecum. These findings indicate that OM1 and OM2 may be used to develop a prophylactic agent for intestinal inflammation and injury in enteric pathogen infection. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the methane (CH4) reducing potential of a combination of prenatal and/or postnatal treatment with coconut oil medium chain fatty acids (CO MCFA) in goat kids. The hypothesis is that influencing rumen function during early life has more chances for success than in the adult life, related to the resilience of the mature rumen microbiota. Forty-eight pregnant does were split into two experimental groups: treated does (D+) received 40 g/d of CO MCFA in a test compound feed, while control does (D-) received a control compound feed, during the last 3 wk of gestation. Twin kids from 10 does of each group were split up into a treated (K+) and nontreated (K-) group, resulting in four experimental groups: D+K+, D+K-, D-K+, and D-K-. The K+ kids received 1.8 mL/d of CO MCFA from birth until 2-wk postweaning (11 wk). Irrespective of treatment, the experimental rearing conditions resulted in absence of rumen protozoa at all sampling times, assessed by quantitative PCR (qPCR). In vitro incubations with rumen fluid at 4 wk old showed 82% lower CH4 production of inoculum from D+K+ kids compared to D-K-kids (P = 0.01). However, this was accompanied by lower total volatile fatty acids (tVFA) production (P = 0.006) and higher hydrogen accumulation (P = 0.008). QPCR targeting the mcrA and rrs genes confirmed a lower abundance of total methanogens (P < 0.02) and total eubacteria (P = 0.02) in D+K+ kids at 4 wk old. Methanogenic activity, as assessed by mcrA expression by RT-qPCR, was also lower in these kids. However, activity did not always reflect methanogen abundance. At 11 and 28 wk old, prenatal and postnatal effects on in vitro fermentation and rumen microbiota disappeared. Nevertheless, lower milk replacer intake in the first 4 wk resulted in reduced BW in K+ kids, persisting until 28 wk of age. Additionally, differences assigned to postnatal treatment were found in papillae density, width, and length in different areas of the rumen, recorded at 28 wk old. Conclusion: prenatal and postnatal supplementation with CO MCFA reduced in vitro CH4 emissions until 4 wk old by depressing methanogen abundance and activity but at the expense of rumen fermentation and eubacterial abundance. Unfortunately, daily gain of K+ kids was suppressed. Some rumen papillae characteristics differed at 28 wk old due to postnatal treatment which ended at 11 wk old, indicating rumen papillary development can be affected by the early-life nutritional circumstances. [ABSTRACT FROM AUTHOR]

Bioprocess for conversion of ethanol and short chain fatty acids (SCFAs) into medium chain fatty acids (MCFAs) is termed as microbial chain elongation. MCFAs are saturated monocarboxylic acids with applications as antimicrobials, corrosion inhibitors and are precursors for the production of biodiesel and bioplastics. In the present study, a two-stage mixed culture fermentation was employed for the production of SCFAs and MCFAs from food waste (FW). In the first stage, FW was hydrolyzed into leachate (contains SCFAs) by the addition of anaerobic bacteria and in the second stage SCFAs present in leachate were converted in to MCFAs by the chain elongation bioprocess. The production of MCFAs such as caproic, heptanoic, caprylic and decanoic acids were demonstrated for 91 days in four different experimental conditions, i.e., control (no bacteria), pure culture ( Clostridium kluyveri ), non-augmentation (only enriched mixed culture), and bio-augmentation ( C. kluyveri bio-augmented with enriched mixed culture). Produced SCFAs, MCFAs and biogas were analysed at different time intervals. Bio-augmented culture showed highest SCFAs (8.9 g/l of butyric acid) and MCFAs (8.1 g/l of caproic acid) production than other conditions. Microbial population was characterized by using denaturing gradient gel electrophoresis (DGGE) analysis with the highest MCFAs producing culture. The bacterial diversity observed contained predominantly Clostridia, Sphingobacteriales, Desulfobacteraceae and Bacillus groups in the bioaugmented mixed culture. Results have depicted the potential of employing the bio-augmentation strategy for the valorization of food waste into useful products like SCFAs and MCFAs. [ABSTRACT FROM AUTHOR]

The macauba palm (Acrocomia aculeata) is native of tropical America and is found mostly in the Cerrados and Pantanal biomes. The fruits provide an oily pulp, rich in long chain fatty acids, and a kernel that encompass more than 50% of lipids rich in medium chain fatty acids (MCFA). Based on biochemical and nutritional evidences MCFA is readily catabolized and can reduce body fat accumulation. In this study, an animal model was employed to evaluate the effect of Acrocomia aculeata kernel oil (AKO) on the blood glucose level and the fatty acid deposit in the epididymal adipose tissue. The A. aculeata kernel oil obtained by cold pressing presented suitable quality as edible oil. Its fatty acid profile indicates high concentration of MCFA, mainly lauric, capric and caprilic. Type 2 diabetic rats fed with that kernel oil showed reduction of blood glucose level in comparison with the diabetic control group. Acrocomia aculeata kernel oil showed hypoglycemic effect. A small fraction of total dietary medium chain fatty acid was accumulated in the epididymal adipose tissue of rats fed with AKO at both low and high doses and caprilic acid did not deposit at all. [ABSTRACT FROM AUTHOR]

Thyroid hormone responsive protein Spot 14 has been consistently associated with de novo fatty acid synthesis activity in multiple tissues, including the lactating mammary gland, which synthesizes large quantities of medium chain fatty acids (MCFAs) exclusively via FASN. However, the molecular function of Spot14 remains undefined during lactation. Spot14-null mice produce milk deficient in total triglyceride and de novo MCFA that does not sustain optimal neonatal growth. The lactation defect was rescued by provision of a high fat diet to the lactating dam. Transgenic mice overexpressing Spot14 in mammary epithelium produced total milk fat equivalent to controls, but with significantly greater MCFA. Spot14-null dams have no diminution of metabolic gene expression, enzyme protein levels, or intermediate metabolites that accounts for impaired de novo MCFA. When [13C] fatty acid products were quantified in vitro using crude cytosolic lysates, native FASN activity was 1.6-fold greater in control relative to Spot14-null lysates, and add back of Spot14 partially restored activity. Recombinant FASN catalysis increased 1.4-fold and C = 14:0 yield was enhanced 4-fold in vitro following addition of Spot14. These findings implicate Spot14 as a direct protein enhancer of FASN catalysis in the mammary gland during lactation when maximal MCFA production is needed.

Cholesterol and lipid homeostasis is important for male fecundity. However, the plasma total cholesterol level does not reflect sperm concentration and motility. Adipose tissue in mammals is the main tissue contributing to the dynamic equilibrium of lipid synthesis and catabolism. However, recent studies suggested that local lipolysis has an important role in male fertility. If so, which plasma lipid metabolism parameter reflects sperm concentration and motility? Leptin receptor-deficient db/db mice show hyperphagia, hyperglycemia, hypercholesterolemia, hypertriglyceridemia, morbid obesity and are reported to be infertile. Impairment of spermatogenesis and sperm motility in db/db mice was observed in our experiments. Medium-chain triglycerides (MCTs) are more quickly metabolized as fuel compared to long-chain triglycerides (LCTs). If the LCTs are replaced with MCTs in the diet, even in hyperphagia, does it affect spermatogenesis and sperm motility? In this study, we investigated the effect of a MCT replacement diet on sperm parameters using db/db mice. Six weeks of MCT replacement diet improved not only spermatogenesis but also the maturation processes in the epididymis for sperm to acquire the ability to move forward. Plasma chylomicron and large VLDL levels showed positive correlation with total and motile sperm concentrations. The MCT replacement diet could be an effective treatment for idiopathic non-obstructive oligozoospermia or asthenozoospermia men with low levels of chylomicron and large VLDL. [ABSTRACT FROM AUTHOR]

Synthesis of medium and long chain triacylglycerols (MLCTs) by lipase-catalyzed interesterification of soybean oil with medium chain triacylglycerols (MCTs) in a solvent-free system is investigated in this study. Firstly, reaction conditions of the interesterification were optimized. Under the optimum conditions (Lipozyme 435 of 8% as catalyst, substrate ratio of 40:60, heating temperature of 90 °C, reaction time of 6 h), MLCTs were obtained in a 74.9% yield Secondly, a two-step purification was conducted to reduce acid, peroxide values and diacylglycerol content to acceptable levels. After the deacidification by the neutralization and silica gel absorption, acid, peroxide values and diacylglycerol content were reduced to 0.14 mg/g, 1.5 mmol/kg and 1.2%, respectively. The determined levels of physicochemical parameters of purified MLCTs fell within the permitted ranges of the Chinese national standard specification for MLCTs. After a two-step purification, a qualified product was produced and can be used in pharmaceutical industry as a component of fat emulsion injection. The process for the preparation of MLCTs is scalable. Differently from previous studies, the aim of this study is to obtain MLCTs products meeting the national standard JX20070100 for structured triacylglycerols. [ABSTRACT FROM AUTHOR]

A 3-wk experiment was conducted to determine the effect of the blend of organic acids (OAs) and medium chain fatty acids (MCFAs) on the growth performance and diarrhea incidence in weanling pigs challenged with enterotoxigenic Escherichia coli K88. Thirty weaned pigs (28 ± 1 d of age, 6.24 ± 0.36 kg) were used in a randomized complete block design experiment with 3 treatments, 5 replicate pens per treatment and 2 animals per pen. The treatments were: (1) control, basal diet (CON); (2) CON + 0.2% blend of OAs and MCFAs (BOM1); (3) CON + 0.4% blend of OAs and MCFAs (BOM2). From d 8 to 10, pigs were orally challenged with 5 mL enterotoxigenic Escherichia coli K88 (10 9 CFU/mL). Pigs fed the blend of OAs and MCFAs diets had greater ( P < 0.05) body weight (BW) than pigs fed CON diet on d 7, 14 and 21 of the experiment. During pre- and post-challenge, the inclusion of the blend of OAs and MCFAs increased ( P < 0.05) average daily gain (ADG), average daily feed intake (ADFI) and gain to feed ratio (G:F) with the exception of G:F during d 8–14. Additionally, pigs fed BOM2 diet had higher ( P < 0.05) final BW and ADG during d 1–21 than those fed BOM1 diet. Before challenge and post-challenge (d 8–14), incidence of diarrhea was lower ( P < 0.05) in BOM1 and BOM2 treatments than that in CON treatment. However, diarrhea incidence was not affected by dietary treatments between d 15 and 21 ( P > 0.05). Results indicated that dietary supplementation with the blend of OAs and MCFAs at 0.2% or 0.4% improved growth performance and reduced diarrhea as indicated by reduced diarrhea incidence in weanling piglets that orally challenged with enterotoxigenic Escherichia coli K88. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease primarily characterized by loss of motor neurons in brain and spinal cord. The death of motor neurons leads to denervation of muscle which in turn causes muscle weakness and paralysis, decreased respiratory function and eventually death. Growing evidence indicates disturbances in energy metabolism in patients with ALS and animal models of ALS, which are likely to contribute to disease progression. Particularly, defects in glucose metabolism and mitochondrial dysfunction limit the availability of ATP to CNS tissues and muscle. Several metabolic approaches improving mitochondrial function have been investigated in vitro and in vivo and showed varying effects in ALS. The effects of metabolic approaches in ALS models encompass delays in onset of motor symptoms, protection of motor neurons and extension of survival, which signifies an important role of metabolism in the pathogenesis of the disease. There is now an urgent need to test metabolic approaches in controlled clinical trials. In addition, more detailed studies to better characterize the abnormalities in energy metabolism in patients with ALS and ALS models are necessary to develop metabolically targeted effective therapies that can slow the progression of the disease and prolong life for patients with ALS. [ABSTRACT FROM AUTHOR]

Epilepsy is too complex to be considered as a disease; it is more of a syndrome, characterized by seizures, which can be caused by a diverse array of afflictions. As such, drug interventions that target a single biological pathway will only help the specific individuals where that drug's mechanism of action is relevant to their disorder. Most likely, this will not alleviate all forms of epilepsy nor the potential biological pathways causing the seizures, such as glucose/amino acid transport, mitochondrial dysfunction, or neuronal myelination. Considering our current inability to test every individual effectively for the true causes of their epilepsy and the alarming number of misdiagnoses observed, we propose the use of the ketogenic diet (KD) as an effective and efficient preliminary/long-term treatment. The KD mimics fasting by altering substrate metabolism from carbohydrates to fatty acids and ketone bodies (KBs). Here, we underscore the need to understand the underlying cellular mechanisms governing the KD's modulation of various forms of epilepsy and how a diverse array of metabolites including soluble fibers, specific fatty acids, and functional amino acids (e.g., leucine, d-serine, glycine, arginine metabolites, and N-acetyl-cysteine) may potentially enhance the KD's ability to treat and reverse, not mask, these neurological disorders that lead to epilepsy. [ABSTRACT FROM AUTHOR]

Introduction: Absorption of dietary fats is generally in the form of emulsions. The present study assessed the preparation and gastrointestinal absorption efficiency of three emulsions of mustard oil containing three types of medium chain fatty acids (MCFAs) in a rat model. Methods: Caprylic acid (C8:0), capric acid (C10:0) and lauric acid (C12:0) were chosen as the MCFAs. Mustard oil emulsions were formulated using each of the MCFAs and lecithin as an emulsifier. The characteristics of the formulations including optical microscopy, particle size, zeta potential analysis and viscosity studies were assessed. Thereafter the intestinal digestion patterns of the three MCFA rich mustard oil emulsions were compared using a single pass perfusion test. Results: The particle size of the emulsions varied between 212.70 nm and 312.70 nm. Physical characterisation such as a zeta potential study confirmed that all emulsions were thermodynamically stable. The absorption study was monitored at 30 min intervals of up to 2 h The absorption of C8:0 emulsion was found to be maximum (27.78%) followed by C10:0 emulsion (24.81%) and C12:0 emulsion (22.50%). The differences in absorption efficiency of the emulsions could be attributed to the smaller chain length of C8:0 which was more rapidly absorbed by the intestine. Conclusion: In vivo gastrointestinal absorption of MCFA rich mustard oil emulsions was compared; caprylic acid-rich mustard oil showed the highest absorption rate in comparison to the other two emulsions. Further in vivo studies are required to establish the mechanism of absorption of structured lipids containing MCFAs. [ABSTRACT FROM AUTHOR]

Chain elongation is a promising technology for production of medium-chain fatty acids (MCFAs). Granular activated carbon (GAC) is commonly used in anaerobic fermentation. Low level CHCl 3 can inhibit methanogenesis and homoacetogenesis at the same time. However, the effect of them on chain elongation performance with highly enriched consortia and simple substrate (i.e., ethanol and acetate) was still unclear. Hence, the effects of CHCl 3 and on MCFAs production and the microbial community was studied here. CHCl 3 displayed fatal effect on chain elongation system when its concentration was higher than 0.1% v/v. 0.05% v/v CHCl 3 was enough to inhibit homoacetogens and further decreased the caproate production efficiency without altering the core bacteria tremendously. GAC was found to be adverse for chain elongation with simple substrate (i.e., ethanol and acetate) and highly enriched microbial consortia dominated by Clostridium sensu stricto , less than 20% electrons were finally distributed in caproate. It might be attributed to other electron consuming activities induced by GAC. • The rapidly enriched microbiome was dominated by Clostridium sensu stricto. • CHCl 3 inhibited homoacetogenesis which decreased the caproate production. • GAC was adverse with simple substrate and highly enriched consortia. • GAC might distract electrons from chain elongation for other activities. [ABSTRACT FROM AUTHOR]

Chocolate is a well-known dessert all over the world. The original chocolate is made from cocoa products: cocoa bean and cocoa butter. Research and Development on low-fat chocolate process were conducted for value addition of coconut oil and Thai fruit. This chocolate processing study composed of (1) coconut oil fractionation, (2) chocolate formulation and (3) shelf-life storage determination. Accordingly, fatty acids composition of the blend of coconut fat and palm oil shortening were determined. It was found that the said product composed of Caproic acid 0.47±0.12%, Caprylic acid 5.65±0.31%, Capric acid 5.14±0.14%, Lauric acid 42.56±0.28%, Myristic acid 16.31±0.18%, Stearic acid 14.55±0.13%, Oleic acid 9.26±0.17%, and Linoleic acid 2.16±0.35%. The saturated fatty acids and unsaturated fatty acids found in this product were 88.57±0.14% and with 11.42±0.81%, respectively. The range of melting point is 260C-330C and oxidative stability is 14.2 to 16.7 hours. The chocolate formula of pale and dark chocolate 1kg composed of coconut fat, palm oil shortening, and lecithin as emulsifier in same amounts such as 250g, 100g, and 0.5g. However, icing sugar and defatted cocoa powder are in different amounts; the icing sugar in pale chocolate and dark chocolate is 350g and 450g while the defatted cocoa powder in pale chocolate and dark chocolate is 200g and 300 g, respectively. These chocolate products have physical properties similar to the chocolate products produced from cocoa butter. The shelf life of these products is 3 months.

The isolation or engineering of algal cells synthesizing high levels of medium-chain fatty acids (MCFAs) is attractive to mitigate the high clouding point of longer chain fatty acids in algal based biodiesel. To develop a more informed understanding of MCFA synthesis is photosynthetic microorganisms, we isolated several algae from Great Salt Lake and screened this collection for MCFA accumulation to identify strains naturally accumulating high levels of MCFA. A diatom, Chaetoceros sp. GSL56, accumulated particularly high levels of C14 (up to 40%), with the majority of C14 fatty acids (~2/3) allocated in triacylglycerols. Using whole cell transcriptome sequencing and de novo assembly, putative genes encoding fatty acid synthesis enzymes were identified. Enzymes from this Chaetoceros sp. were expressed in the cyanobacterium Synechococcus sp. PCC 7002 to validate gene function and to determine whether eukaryotic enzymes lacking bacteria evolutionary control mechanisms could be used to improve MCFA production in this promising production strains. Replacement of the Synechococcus 7002 native FabH with a Chaetoceros ketoacyl-ACP synthase III increased MCFA synthesis up to five fold. The level of increase is dependent on promoter strength and culturing conditions.

A partir do desenvolvimento de métodos mais precisos para a avaliação de lipídeos, diversos compostos têm sido descobertos e estudados como forma de enriquecer e melhorar dietas para atender às necessidades dos animais. O triglicerídeo é o principal componente lipídico da dieta e fonte de ácidos graxos que são utilizados para a síntese de outros lipídicos importantes como os fosfolípideos. Os ácidos graxos dos fosfolipídeos possuem papel fundamental na sinalização celular e são substratos das enzimas específicas durante o processo de produção de mediadores de respostas imunológicas. Diversos estudos têm evidenciado a participação de grupos de ácidos graxos das séries ômega 3 e 6 influenciando as respostas inflamatórias em cães e gatos. A deficiência de ácido araquidônico em gatos, por exemplo, pode ser suprida pelo acréscimo de AA pré formado ou pela inclusão de ácido γ-linolênico na dieta, que mostrou-se eficiente na sustentação dos níveis de ácido araquidônico exigidos por gatos adultos. Há evidências de que ácidos graxos de cadeia média (AGCM) proporcionam maior incremento calórico durante o processo de oxidação celular, sugerindo sua funcionalidade sobre o controle da obesidade. Outros compostos lipídicos têm sido avaliados quanto a sua participação no processo de controle de ganho de peso. A ausência de um AA nos diacilgliceróis (DAG) pode ser na posição sn 2 ou sn 3 do glicerol gerando DAGs diferentes. O 1,3 DAG quando comparado ao TAG resulta em diferentes efeitos metabólicos que suportam a hipótese de que o acréscimo de DAG na dieta aumenta a oxidação hepática ou intestinal de lipídeos, limitando a deposição de ácidos graxos em triglicerídeos junto ao tecido adiposo.Following the development of more accurate methods for lipid evaluation, various compounds have been discovered and studied as a way to improve and enrich diets to meet the animal requirements. Triglycerides are the major lipid component of diets and source of fatty acids that are used in the synthesis of important compounds as phospholipids. The fatty acids from phospholipids play a fundamental role in cell signaling and are substrates for specific enzymes in the synthesis of immune response mediators. Several studies have shown the involvement of fatty acids, omega 3 and 6 series as influencing the inflammatory responses in dogs and cats. The deficiency of arachidonic acid in cats, for example, can be supplied by preformed arachidonic acid or by addition of γ-linolenic acid in the diet, which in turn can sustain the arachidonic acid levels required by adult cats. Evidences suggest that medium chain fatty acids (MCFAs) trigger greater energy expenditure during cellular oxidation, thus indicating their use as an aid for weight control in obesity. Other lipid compounds are under evaluation in their possible effects in the weight gain process in dogs and cats. This absence of one FA in the DAG can be at the sn2 or sn3 position in glycerol, and thus generating different DAGs. The 1,3 DAG when compared to TAG results in different metabolic effects which support the hypothesis that the addition of DAG in diets increases the hepatic or intestinal oxidation of lipids, thus limiting the deposition of fatty acids in adipose tissue triglycerides.

[Display omitted] • MCFAs obtained from liquor brewing wastewater by Microbial electrosynthesis. • The −1.0 V cathode potential and CO 2 supply increased the MCFAs yield by 32.6 %. • Co-electron donors in wastewater effectively avoided the competing acrylate pathway. • Clostridium sensu Stricto 12 and Eubacterium were key genera for MCFAs production. Chinese liquor brewing wastewater (CLBW) is rich in ethanol and lactate, but the high extraction cost limits the recovery of carbon resources. In this study, microbial electrosynthesis (MES) was used to upgrade CLBW to biofuels such as medium chain fatty acids (MCFAs), and the effect of different cathode potentials and CO 2 supply on the MES production performance was investigated. The results showed that CLBW could be upgraded to the highest caproate concentration and selectivity of 7.98 g/L and 47.10% under −1.0 V/CO 2 condition, which were 32.6% and 31.9% higher than the control group. The further decrease of the cathode potential led to the deterioration of MCFAs production performance. Electron donor metabolic analysis showed that −1.0 V promoted the conversion of electron donors to caproate. The superiority of −1.0 V/CO 2 condition was further confirmed by pH analysis, the weakly basic pH avoided the toxicity of undissociated carboxylic acids. Electrochemical analysis also indicated that stronger electron transfer ability and higher electrochemical activity occurred at −1.0 V/CO 2 condition. The results of microbial diversity analysis showed that Clostridium sensu stricto 12 and Eubacterium would be enriched under −1.0 V/CO 2 condition. In addition, co-electron donors in CLBW could effectively avoid the competing acrylate pathway. This study provides a new pathway for MCFAs production. [ABSTRACT FROM AUTHOR]

[Display omitted] • Caproate was produced from liquor fermentation waste without external EDs. • Highest carbon conversion and MCFAs selectivity at 40% substrate concentration. • Ethanol utilization and products formation were promoted by Electro-fermentation. • Caproiciproducens was able to metabolize high concentrations of lactate substrates. Substrate toxicity would limit the upgrading of waste biomass to medium-chain fatty acids (MCFAs). In this work, two fermentation modes of electro-fermentation (EF) and traditional fermentation (TF) with different concentration of liquor fermentation waste (20%, 40%, 60%) were used for MCFAs production as well as mechanism investigation. The highest caproate (4.04 g/L) and butyrate (13.96 g/L) concentrations were obtained by EF at 40% substrate concentration. TF experiments showed that the substrate concentration above 40% severely inhibited ethanol oxidation and products formation. Compared with TF mode, the total substrates consumption and product yields under EF mode were significantly increased by 2.6%–43.5% and 54.0%–83.0%, respectively. Microbial analysis indicated that EF effectively alleviated substrate toxicity and enriched chain elongation bacteria, particularly Clostridium_sensu_stricto 12, thereby promoting ethanol oxidation and products formation. Caproiciproducens tolerated high-concentration substrates to ensure normal lactate metabolism. This study provides a new way to produce MCFAs from high concentration wastewater. [ABSTRACT FROM AUTHOR]