Anti-Obesity Effects of Dietary d-Allulose and Medium-Chain Triglycerides in High-Fat Diet-Fed Rats

d-Allulose, a rare sugar, exerts anti-obesity effects by inhibiting hepatic lipogenesis and promoting energy expenditure. Medium-chain triglycerides (MCTs) consist of three medium-chain fatty acids connected by glycerol. MCTs have been extensively investigated for their ability to reduce body fat accumulation. We previously investigated the anti-obesity effects of a combination of dietary d-allulose and MCT (5% - 13%) in rats;however, we could not confirm the anti-obesity effects of MCT or observed synergetic effects between d-allulose and MCT on body fat loss. We speculated that our previous studies were influenced by the excessive amount of MCT in the diets. Therefore, in this study, we aimed to investigate the anti-obesity effects of the simultaneous intake of d-allulose and MCT in rats fed an obesity-inducing high-fat diet with a low amount of MCTs (2%). Thirty-two male Wistar rats (3-week-old) were randomly divided into four groups: control, d-allulose, MCT, and d-allulose + MCT groups. Rats in each group were fed ad libitum on a control (no d-Allulose or MCT), 5% d-allulose, 2% MCT, or 5% d-allulose + 2% MCT diets for 16 weeks. Abdominal adipose tissue weights were significantly lower in the d-allulose diet group than in the control group, whereas no differences were observed between results of the MCT-supplemented groups. The total body fat mass was significantly lower in the d-allulose and MCT diet groups than in the control group, but no differences were observed between the MCT-supplemented groups. These results suggested that anti-obesity effects of dietary d-allulose were observed, and the effects of dietary MCTs were weaker than those of d-allulose. Moreover, we confirmed the interaction between dietary d-allulose and MCT on indicators of obesity. Interestingly, their effects were not synergistic, as MCT supplementation offset the anti-obesity effects of dietary d-allulose. However, the specific mechanisms underlying those effects remain unknown, warranting further investigation.

Efficacy of medium-chain fatty acid salts distilled from coconut oil against two enteric pathogen challenges in weanling piglets

Background:The search for alternatives to antibiotics in pig production has increased the interest in natural resources with antimicrobial properties,such as medium-chain fatty acids(MCFA)as in-feed additives.This study evaluated the potential of a novel blend of MCFA salts(DIC)from distilled coconut oil with a lauric acid content to reduce enteropathogens and control intestinal diseases around weaning.Two experimental disease models were implemented in early-weaned piglets,consisting of two oral challenges:Salmonella Typhimurium(1.2×10~8 CFU)or enterotoxigenic Escherichia coli(ETEC)F4(1.5×10~9 CFU).The parameters assessed were:animal performance,clinical signs,pathogen excretion,intestinal fermentation,immune-inflammatory response,and intestinal morphology.Results:The Salmonella challenge promoted an acute course of diarrhea,with most of the parameters responding to the challenge,whereas the ETEC F4 challenge promoted a mild clinical course.A consistent antipathogenic effect of DIC was observed in both trials in the hindgut,with reductions in Salmonella spp.plate counts in the cecum(P=0.03)on d 8 post-inoculation(PI)(Salmonella trial),and of enterobacteria and total coliform counts in the ileum and colon(P<0.10)on d 8 PI(ETEC F4 trial).When analyzing the entire colonic microbiota(16 S rRNA gene sequencing),this additive tended(P=0.13)to reduce the Firmicutes/Bacteroidetes ratio and enriched Fibrobacteres after the Salmonella challenge.In the ETEC F4 challenge,DIC prompted structural changes in the ecosystem with increases in Dialister,and a trend(P=0.14)to increase the Veillonellaceae family.Other parameters such as the intestinal fermentation products or serum pro-inflammatory mediators were not modified by DIC supplementation,nor were the histological parameters.Only the intraepithelial lymphocyte(IEL)counts were lowered by DIC in animals challenged with Salmonella(P=0.07).With ETEC F4,the IEL counts were higher with DIC on d 8 PI(P=0.08).Conclusions:This study confirms the potential activity of this MCFA salts mixture to reduce intestinal colonization by opportunistic pathogens such as Salmonella or E.coli and its ability to modulate colonic microbiota.These changes could explain to some extent the local immune cell response at the ileal level.

Medium-Chain Triglyceride Activated Brown Adipose Tissue and Induced Reduction of Fat Mass in C57BL/6J Mice Fed High-fat Diet

Objective To investigate activation of brown adipose tissue （BAT） stimulated by medium-chain triglyceride （MCT）. Methods 30 Male C57BL/6J obese mice induced by fed high fat diet （HFD） were divided into 2 groups, and fed another HFD with 2% MCT or long-chain triglyceride （LCT） respectively for 12 weeks. Body weight, blood biochemical variables, interscapular brown fat tissue （IBAT） mass, expressions of mRNA and protein of beta 3-adrenergic receptors （β3-AR）, uncoupling protein-1 （UCP1）, hormone sensitive lipase （HSL）, protein kinase A （PKA）, and adipose triglyceride lipase （ATGL） in IBAT were measured. Results Significant decrease in body weight and body fat mass was observed in MCT group as compared with LCT group （P〈O.05） after 12 weeks. Greater increases in IBAT mass was observed in MCT group than in LCT group （P〈O.05）. Blood TG, TC, LDL-C in MCT group were decreased significantly, meanwhile blood HDL-C, ratio of HDL-C/LDL-C and norepinephrine were increased markedly. Expressions of mRNA and protein of β3-AR, UCP1, PKA, HSL, ATGL in BAT were greater in MCT group than in LCT group （P〈O.05）. Conclusion Our results suggest that MCT stimulated the activation of BAT, possible via norepinephrine pathway, which might partially contribute to reduction of the body fat mass in obese mice fed high fat diet.

Medium-chain fatty acids and monoglycerides as feed additives for pig production:towards gut health improvement and feed pathogen mitigation

Ongoing challenges in the swine industry,such as reduced access to antibiotics and virus outbreaks(e.g.,porcine epidemic diarrhea virus,African swine fever virus),have prompted calls for innovative feed additives to support pig production.Medium-chain fatty acids(MCFAs)and monoglycerides have emerged as a potential option due to key molecular features and versatile functions,including inhibitory activity against viral and bacterial pathogens.In this review,we summarize recent studies examining the potential of MCFAs and monoglycerides as feed additives to improve pig gut health and to mitigate feed pathogens.The molecular properties and biological functions of MCFAs and monoglycerides are first introduced along with an overview of intervention needs at different stages of pig production.The latest progress in testing MCFAs and monoglycerides as feed additives in pig diets is then presented,and their effects on a wide range of production issues,such as growth performance,pathogenic infections,and gut health,are covered.The utilization of MCFAs and monoglycerides together with other feed additives such as organic acids and probiotics is also described,along with advances in molecular encapsulation and delivery strategies.Finally,we discuss how MCFAs and monoglycerides demonstrate potential for feed pathogen mitigation to curb disease transmission.Looking forward,we envision that MCFAs and monoglycerides may become an important class of feed additives in pig production for gut health improvement and feed pathogen mitigation.

Inhibition of African swine fever virus in liquid and feed by medium-chain fatty acids and glycerol monolaurate

Background:The ongoing African swine fever virus(ASFv)epidemic has had a major impact on pig production globally and biosecurity efforts to curb ASFv infectivity and transmission are a high priority.It has been recently identified that feed and feed ingredients,along with drinking water,can serve as transmission vehicles and might facilitate transboundary spread of ASFv.Thus,it is important to test the antiviral activity of regulatory compatible,antiviral feed additives that might inhibit ASFv infectivity in feed.One promising group of feed additive candidates includes medium-chain fatty acids(MCFA)and monoglyceride derivatives,which are known to disrupt the lipid membrane surrounding certain enveloped viruses and bacteria.Results:The antiviral activities of selected MCFA,namely caprylic,capric,and lauric acids,and a related monoglyceride,glycerol monolaurate(GML),to inhibit ASFv in liquid and feed conditions were investigated and suitable compounds and inclusion rates were identified that might be useful for mitigating ASFv in feed environments.Antiviral assays showed that all tested MCFA and GML inhibit ASFv.GML was more potent than MCFA because it worked at a lower concentration and inhibited ASFv due to direct virucidal activity along with one or more other antiviral mechanisms.Dose-dependent feed experiments further showed that sufficiently high GML doses can significantly reduce ASFv infectivity in feed in a linear manner in periods as short as 30 min,as determined by infectious viral titer measurements.Enzyme-linked immunosorbent assay(ELISA)experiments revealed that GML treatment also hinders antibody recognition of the membrane-associated ASFv p72 structural protein,which likely relates to protein conformational changes arising from viral membrane disruption.Conclusion:Together,the findings in this study indicate that MCFA and GML inhibit ASFv in liquid conditions and that GML is also able to reduce ASFv infectivity in feed,which may help to curb disease transmission.

Lipase Catalyzed Synthesis of Medium-chain Biodiesel from Cinnamonum camphora Seed Oil

The non-edible camphor tree seed oil was extracted and catalyzed by immobilized lipase for biodiesel production. The oil yield from camphor tree seeds reached 35.2% of seed weight by twice microwave-assisted extractions. Gas chromatography showed that free fatty acid content in camphor tree seed oil was 1.88%, and the main fatty acids were capric acid(53.4%) and lauric acid(38.7%). With immobilized lipase Candida sp. 99–125as catalyst, several important factors for reaction conditions were examined through orthogonal experiments.The optimum conditions were obtained: water content and enzyme loading were both 15% with a molar ratio of 1:3.5(oil/ethanol), and the process of alcoholysis was in nine steps at 40 °C for 24 h, with agitation at170 r·min-1. As a result, the medium-chain biodiesel yield was 93.5%. The immobilized lipase was stable when it was used repeatedly for 210 h.

Effect of replacement of soybean oil by Hermetia illucens fat on performance,digestibility,cecal microbiome,liver transcriptome and liver and plasma lipidomes of broilers

Background In contrast to protein-rich insect meal,the feed potential of insect fat is generally less explored and knowledge about the suitability of insect fat as a fat source specifically in broiler diets is still limited.In view of this,the present study aimed to comprehensively investigate the effect of partial(50%) and complete replacement of soybean oil with insect fat from Hermetia illucens(HI) larvae in broiler diets on performance,fat digestibility,cecal microbiome,liver transcriptome and liver and plasma lipidomes.Thus,100 male,1-day-old Cobb 500 broilers were randomly assigned to three groups and fed three different diets with either 0(group HI-0,n cens(HI) larvae fat for 35 d.= 30),2.5%(group HI-2.5,n %(HI-5.0,n = 35) or 5.0= 35) Hermetia illuResults Body weight gain,final body weight,feed intake,and feed:gain ratio during the whole period and apparent ileal digestibility coefficient for ether extract were not different between groups.Cecal microbial diversity did not differ between groups and taxonomic analysis revealed differences in the abundance of only four low-abundance bacterial taxa among groups;the abundances of phylum Actinobacteriota,class Coriobacteriia,order Coriobacteriales and family Eggerthellaceae were lower in group HI-5.0 compared to group HI-2.5(P < 0.05).Concentrations of total and individual short-chain fatty acids in the cecal digesta were not different between the three groups.Liver transcriptomics revealed a total of 55 and 25 transcripts to be differentially expressed between groups HI-5.0 vs.HI-0 and groups HI-2.5 vs.HI-0,respectively(P < 0.05).The concentrations of most lipid classes,with the exception of phosphatidylethanolamine,phosphatidylglycerol and lysophosphatidylcholine in the liver and cholesterylester and ceramide in plasma(P < 0.05),and of the sum of all lipid classes were not different between groups.Conclusions Partial and complete replacement of soybean oil with HI larvae fat in broiler diets had no effect on growth performance and only modest,but no adverse effects on the cecal microbiome and the metabolic health of broilers.This suggests that HI larvae fat can be used as an alternative fat source in broiler diets,thereby,making broiler production more sustainable.

Efficacy and safety of modified medium-chain triglyceride ketogenic diet in patients with drug-resistant epilepsy

Background Medium-chain triglyceride ketogenic diet(MCTKD)is previously less commonly used in China.This study was aimed to assess the efficacy and safety of the modified MCTKD in the treatment of drug-resistant epilepsy in Chinese patients.Methods Patients with drug-resistant epilepsy were enrolled to receive treatment with modified MCTKD in Guangdong Sanjiu Brain Hospital during December 2020 and September 2022.The modified MCTKD contained fat that provided 50–70%of the total energy,as well as proteins and carbohydrates that provided 20–30%and 20%of energy,respectively.The fat component was composed of 20–30%medium-chain triglycerides(MCTs)and 30–40%long-chain triglycerides.The efficacy and safety of the diet were assessed at 1,3 and 6 months.Results A total of 123 patients aged 2.5 to 65 years,were included in this study.The response rates at 1,3 and 6 months were 49.6%,43.1%,and 30.9%,respectively.The seizure freedom rates at 1,3 and 6 months were 12.2%,10.6%,and 6.5%,respectively.The retention rates at 1,3 and 6 months were 98.4%,65.0%and 33.3%respectively.Side effects occurred in 21.14%of patients,which were predominantly gastrointestinal symptoms such as abdominal pain,diarrhea,vomiting,and constipation,and most of them resolved after dietary adjustments.A total of 82 patients(66.7%)discontinued the treatment with the reason of refusing to eat(8.1%),poor efficacy(35.0%),poor compliance(4.9%),and inability to follow-up(9.8%).Only 4 patients(3.3%)withdrew the diet due to side effects.Conclusions The modified MCTKD with MCTs providing 20–30%of energy has a good safety in patients with drug-resistant epilepsy,but its effectiveness needs to be enhanced.Further modifications of MCTKD with an optimal energy ratio are required to achieve a better efficacy and safety.

Evaluation of dynamic effects of dietary medium-chain monoglycerides on performance,intestinal development and gut microbiota of broilers in large-scale production

Medium-chain monoglycerides(MG)have been reported to affect the productive performance,gut microbiota and health of broiler chickens reared in ideal experimental conditions at home and abroad.However,the effects of MG on performance,intestinal development and gut microbiota of chickens in large-scale farms during different feed stages remain unknown.The present study was conducted on a modern farm with a total of 12,000 yellow feathered broiler chicks that were randomly allotted to 2groups(1000 chicks/replicate,6 replicates/group)for a 70-day trial.The control group(CON group)received a basal diet,and the treated group(MG group)was fed a basal diet containing 300 mg/kg mixed MG.The results revealed that dietary MG significantly(P<0.05)increased the body weight and average feed intake,but notably reduced the feed conversion and mortality of chickens in large-scale production during the starter phase.The villus height of the duodenum in the MG group at 1,2 and 7 wk of age increased notably,and the villus height to crypt depth ratio at 1,2,5 and 10 wk of age was improved.Dietary MG decreased the serum insulin content of chickens at 5,7 and 10 wk of age,and decreased the serum lipopolysaccharide at 3 and 7 wk of age.The triglyceride level of chickens at 3,5 and 10 wk of age and the low-density lipoprotein cholesterol level of chickens at 7 and 10 wk of age in the MG group decreased notably,while the high-density lipoprotein cholesterol increased significantly.Moreover,MG supplementation selectively increased the relative abundance of genus Bacteroides(family Bacteroidaceae)and Lachnospiraceae_NK4A136_group,but decreased the content of genus Rikenellaceae_RC9_gut_group,Collinsella and family Barnesiellaceae in the cecum of chickens at 3,7 and 10 wk of age.Conclusively,these findings showed that dietary MG notably enhanced chicken performance,health and feed nutrient utilization at early ages by regulating gut microbiota,intestinal development and serum biochemical indices.

Effect of medium-chain triglycerides on growth performance, nutrient digestibility,plasma metabolites and antioxidant capacity in weanling pigs

The aim of this study was to investigate the effect of medium-chain triglycerides(MCTs) on growth performance, nutrient digestibility, plasma metabolites and antioxidant capacity in weanling pigs. A total of 160 weanling(Duroc × Landrace x Yorkshire) pigs(age: 21 ± 1 d; body weight: 7.50 ± 0.28 kg) were randomly allotted to 4 treatments, receiving the following diets for 28 d: control diet [containing 3.5%soybean oil(SO)], MCT1 diet(containing 0.7% MCTs and 2.8% SO), MCT2 diet(containing 1.4% MCTs and2.1% SO) and MCT3 diet(containing 2.1% MCTs and 1.4% SO). Dietary inclusion of MCTs improved the average daily gain and feed efficiency(FE) of pigs compared with the control during the first 2 weeks post-weaning(P < 0.05). A similar positive effect was also observed for the overall FE in MCT2 group(P < 0.05). Compared with the control, apparent total tract digestibility(ATTD) of ether extract was improved by MCT2 and MCT3 treatment from day 12-14 post-weaning(P < 0.05). In addition, MCT2 treatment also exerted a beneficial effect on the ATTD of dry matter(P < 0.05). The increased total protein concentration and decreased urea nitrogen and malondialdehyde levels of plasma were observed in both MCT2 and MCT3 groups on day 14 post-weaning(P < 0.05). In conclusion, MCTs could improve growth performance, nutrients utilization, and antioxidant ability of weanling piglets.

Medium-chain acyl-CoA dehydrogenase deficiency: prevalence of ACADM pathogenic variants c.985A>G and c.199T>C in a healthy population in Rio Grande do Sul, Brazil

Objectives::To investigate the prevalence of ACADM pathogenic variants, c.985A>G and c.199T>C, for medium chain acyl CoA dehydrogenase deficiency (MCADD) in a healthy population in the southern region of Brazil. Methods::This was an observational cross-sectional study with a convenience sampling strategy. The participants were recruited from the blood bank of the Hospital de Clínicas of Porto Alegre, Brazil. A total of 1000 healthy individuals from the state of Rio Grande do Sul were included. Genotyping for the c.199T>C and c.985A>G variants was performed using real-time polymerase chain reaction (PCR) and the PCR-restriction fragment length polymorphism (RFLP) technique, respectively. Individuals considered heterozygous for c.985A>G were subjected to additional acylcarnitine profile analysis using tandem mass spectrometry. Carrier frequency was obtained by calculating the ratio of heterozygous individuals to the total number of individuals analyzed and reported with a 95% confidence interval. Allele and genotype frequencies were calculated based on the Hardy-Weinberg equilibrium.Results::The c.985A>G variant was detected as heterozygotes in three individuals (frequency of the heterozygous genotype = 1:333, allele frequency= 0.0015, minimum frequency of MCADD= 1:444,444) whose acylcarnitine profiles were within normal limits. The c.199T>C variant was not identified.Conclusions::Considering the small sample size and associated allelic heterogeneity with MCADD, these findings are believed to denote the rarity or underdiagnosis of MCADD in southern Brazil. This study provides evidence for the need for further investigation to ascertain the contribution of these diseases to child morbidity and mortality in the country.

Short-and medium-chain chlorinated paraffins in imported commercial dry cat and dog food in China:Concentrations,distributions and risk assessment

Chlorinated paraffins(CPs)are produced in large amounts and used worldwide.Dietary intake is the primary pathway for the exposure of pets to CPs,but limited information is available concerning the potential contamination of pet food by CPs.In the present study,the concentrations and congener group profiles of short-chain CPs(SCCPs)and medium-chain CPs(MCCPs)were assessed in 35 imported commercial dry cat and dog foods collected in China,and the estimated daily intakes of SCCPs and MCCPs for cats and dogs through the consumption of such foods was calculated.The concentrations of SCCPs and MCCPs in the cat and dog foods were determined to be in the ranges of 108e45,300 ng/g(median:1340 ng/g)and 3.8e52,700 ng/g(median:11 ng/g),respectively.The predominant congener groups were C10Cl6 for SCCPs and C14Cl7-8 for MCCPs.The high levels of CPs found in certain pet foods suggest the potential for adverse health effects.

Peracetic acid(PAA)-based pretreatment effectively improves medium-chain fatty acids(MCFAs)production from sewage sludge

Peracetic acid(PAA),known for its environmentally friendly properties as a oxidant and bactericide,is gaining prominence in decontamination and disinfection applications.The primary product of PAA oxidation is acetate that can serve as an electron acceptor(EA)for the biosynthesis of medium-chain fatty acids(MCFAs)via chain elongation(CE)reactions.Hence,PAA-based pretreatment is supposed to be beneficial for MCFAs production from anaerobic sludge fermentation,as it could enhance organic matter availability,suppress competing microorganisms and furnish EA by providing acetate.However,such a hypothesis has rarely been proved.Here we reveal that PAA-based pretreatment leads to significant exfoliation of extracellular polymeric substances(EPS)from sludge flocs and disruption of proteinic secondary structures,through inducing highly active free radicals and singlet oxygen.The production of MCFAs increases substantially to 11,265.6 mg COD L^(-1),while the undesired byproducts,specifically long-chain alcohols(LCAs),decrease to 723.5 mg COD L^(-1).Microbial activity tests further demonstrate that PAA pretreatment stimulates the CE process,attributed to the up-regulation of functional genes involved in fatty acid biosynthesis pathway.These comprehensive findings provide insights into the effectiveness and mechanisms behind enhanced MCFAs production through PAA-based technology,advancing our understanding of sustainable resource recovery from sewage sludge.

Road to full bioconversion of biowaste to biochemicals centering on chain elongation: A mini review

Production of biochemicals from waste streams has been attracting increasing worldwide interest to achieve climate protection goals.Chain elongation(CE)for production of mediumchain carboxylic acids(MCCAs,especially caproate,enanthate and caprylate)from diverse biowaste has emerged as a potential economic and environmental technology for a sustainable society.The present mini review summarizes the research utilizing various synthetic or real waste-derived substrates available for MCCA production.Additionally,the microbial characteristics of the CE process are surveyed and discussed.Considering that a large proportion of recalcitrantly biodegradable biowaste and residues cannot be further utilized by CE systems and remain to be treated and disposed,we propose here a loop concept of bioconversion of biowaste to MCCAs making full use of the biowaste with zero emission.This could make possible an alternative technology for synthesis of value-added products from a wide range of biowaste,or even non-biodegradable waste(such as,plastics and rubbers).Meanwhile,the remaining scientific questions,unsolved problems,application potential and possible developments for this technology are discussed.

Coconut oil:what do we really know about it so far?

In recent years,coconut oil has emerged as a potential‘miracle’food.Some media vehicles and health specialists assure that this fat is capable of promoting health benefits,such as weight reduction,cholesterol lowering,prevention of cardiovascular diseases,and anti-inflammatory effect,among others.These claims are used to market the product and boost its sales by coconut oil companies.However,governmental regulatory agencies in many countries are still sceptical about the benefits obtained by the consumption of coconut oil due to its high-saturated fatty acid content.In light of such controversy,this review focused on analysing the published literature on the alleged health claims,in order to investigate if there is enough scientific evidence to support them.It was verified that the metabolism of lauric acid,the major fatty acid in coconut oil,remains unclear.Many studies reported that the product was not efficient in weight loss.Also,it has been reported that the consumption of coconut oil increased low-density lipoprotein cholesterol,consequently increasing the risk of cardiovascular diseases.In general,the studies present conflicting results and there is a lack of long-term human-based clinical trials.Therefore,as a saturated fat,coconut oil should be consumed with moderation and the health allegations should not be used to market the product,once they are not scientifically proven so far.