Isobutyric Acid Research Articles

Dose-Response Absorption Kinetics of Oral L-Beta-Aminoisobutyric Acid (L-BAIBA) Supplementation in Healthy Men and Women

L-Beta-amino isobutyric acid (L-BAIBA) is a myokine produced in skeletal muscle during exercise and has been shown to impact carbohydrate and fat metabolism in both animals and humans. This study was designed to determine the rate and extent to which L-BAIBA appeared in human plasma after oral ingestion. In a randomized, double-blind, placebo-controlled, crossover fashion, six males and 6 females (N = 12; 24 ± 5 yrs; 173.6 ± 12.0 cm; 72.3 ± 11.3 kg; 21.0 ± 7.0 body fat %) completed a single-dose supplementation protocol of placebo (PLA), L-BAIBA at 250 mg (B250), 500 mg (B500), 1,500mg (B1500), and 1,500mg of valine (V1500). Participants fasted overnight (8–10 h) and consumed their dose with 8–12 fluid ounces of cold water. Venous blood samples were collected 0, 30, 60, 90, 120, 180, 240 and 300 min after ingestion and analyzed for L-BAIBA. Complete blood counts and comprehensive metabolic panels were analyzed 0 and 300 min after ingestion. Peak concentration (CMax) and area under the curve (AUC) were calculated for all variables. Baseline L-BAIBA levels were not different between conditions (p = 0.46). The observed AUC for B1500 (30,513 ± 9190 µM•300 min) was significantly higher than B500 (11,087 ± 3378 µM•300 min, p < 0.001), B250 (7081 ± 2535 µM•300 min, p < 0.001), V1500 (2837 ± 2107 µM•300 min, p < 0.001), and PLA (2836 ± 2061 µM•300 min, p < 0.001). Similarly, L-BAIBA CMax for B1500 (278.1 ± 52.1 µM) was significantly higher than all other supplement conditions: B500 (95.4 ± 33.5 µM, p < 0.001), B250 (63.3 ± 61.1 µM, p < 0.001), V1500 (10.1 ± 7.2 µM, p < 0.001), PLA (11.0 ± 7.1 µM, p = 0.001). AUC and CMax for B500 was significantly higher than B250 (p < 0.001), V1500 (p < 0.001), and PLA (p < 0.001). BAIBA AUC for B250 was significantly higher than V1500 (p < 0.001) and PLA (p < 0.001). No clinically significant changes in blood-based markers of health or adverse events were observed across the study protocol. L-BAIBA doses of 250 mg, 500 mg, and 1500 mg produced significantly greater concentrations of plasma L-BAIBA across a five-hour measurement window when compared to a 1500 mg dose of valine or a placebo. Follow-up efficacy studies on resting and exercise metabolism should be completed to assess the impact of L-BAIBA supplementation in normal weight and overweight individuals. Retrospectively registered on April 22, 2022 at ClinicalTrials.gov as NCT05328271.

PSV-A-12 The Influence of Calcium Dose and Olive Meal on in-Vitro Rumen Fermentation Characteristics

Abstract Rumen fluid from three beef steers (480 ± 10 kg), fitted with rumen canulae, were used to investigate the impact of Ca dose and olive meal on in vitro rumen fermentation characteristics. Steers were fed a high concentrate finishing diet for 21d, and rumen fluid was collected from each steer 2h post-feeding. A 2 x 4 factorial arrangement of treatments was used for this experiment. Factors included: 1) 0 or 5% olive meal and 2) Ca dose: 0, 0.02, 0.04, and 0.08% Ca from CaCl2. A McDougall’s buffer-rumen fluid mixture (1:1; 30 mL) was added to conical tubes containing 0.5g of the ground basal diet and incubated at 39°C for 0, 4, 8, and 12h (5 replicates per treatment per time point). After incubation, supernatant was removed for VFA analysis and the remaining digesta was dried to determine DM disappearance (DMD). At 4 and 8h post incubation digestion tubes containing 0.04% Ca had greater (P &amp;lt; 0.001) DMD when compared to all other Ca doses. At 12h post incubation, DMD was greater (P &amp;lt; 0.001) in digestion tubes containing 0.02% and 0.08% Ca compared to all other Ca doses. At 8h post incubation, molar proportions of acetic acid were greater (P &amp;lt; 0.03) in digestion tubes containing olive meal compared to no olive meal and were greater (P &amp;lt; 0.001) in digestion tubes containing 0.08% Ca compared to all other Ca doses. At 12h post incubation, isobutyric acid (P &amp;lt; 0.01) and butyric acid (P &amp;lt; 0.02) were greater in digestion tubes containing 0.02% and 0.04% Ca compared to all other Ca doses. Butyric acid was lesser (P &amp;lt; 0.02) with olive meal inclusion at 12h. Total VFA concentrations were similar across treatments. These data suggest that Ca and olive meal can impact in vitro fermentation characteristics.

Short-Chain Fatty Acid Reference Ranges in Pregnant Women from a Mediterranean Region of Northern Spain: ECLIPSES Study.

Maternal short-chain fatty acids (SCFAs) play a critical role in fetal development and metabolic programming. However, an important gap in the analysis of such relationships is the lack of reference values in pregnant women. Therefore, we establish serum SCFA percentile reference ranges both early and later in pregnancy in a population from a Mediterranean region of Northern Spain. A population-based follow-up study involving 455 healthy pregnant women (mean age 30.6 ± 5.0 years) from the ECLIPSES study is conducted. Sociodemographic, obstetric, anthropometric, lifestyle, dietary variables and blood samples were collected in the first and third trimesters. Serum SCFA concentrations were measured by LC-MS/MS. The 2.5/97.5 percentiles of the reference interval for serum acetic, propionic, isobutyric, and butyric acids were 16.4/103.8 µmol/L, 2.1/5.8 µmol/L, 0.16/1.01 µmol/L and 0.32/1.67 µmol/L in the first trimester of pregnancy, respectively. In the third trimester, butyrate levels increased with most of the maternal factors and categories studied, while acetic acid and isobutyric acid decreased only in some maternal categories. Propionic acid was not affected by maternal factors. Reference ranges did not vary with maternal age, body weight, social class or diet, but decreased with smoking, high physical activity, low BMI and primiparity. This study establishes for the first-time SCFAs reference ranges in serum for women in our region in both early and late pregnancy. This information can be useful to monitor pregnancy follow-up and detect risk values.

Soybean isoflavones modulate gut microbiota to benefit the health weight and metabolism.

Soybean isoflavones (SIs) are widely found in food and herbal medicines. Although the pharmacological activities of SIs have been widely reported, their effects on the intestinal microecology of normal hosts have received little attention. Five-week-old Kunming (KM) mice were administered SIs (10 mg/kg/day) for 15 days. Food intake, body weight, and digestive enzyme activity were measured. Small intestine microbiota, including lumen-associated bacteria (LAB) and mucosa-associated bacteria (MAB), were analyzed using 16S ribosomal ribonucleic acid (16S rRNA) gene sequencing. Short-chain fatty acids (SCFAs) were analyzed using gas chromatography-mass spectrometry (GC-MS). The results showed that the mice that consuming SIs showed a higher food intake but a lower body weight gain rate than that of normal mice. Sucrase, cellulase, and amylase activities reduced, while protease activity increased after SIs intervention. Moreover, SIs increased the intestinal bacterial diversity in both LAB and MAB of normal mice. The composition of LAB was more sensitive to SIs than those of MAB. Lactobacillus, Adlercreutzia, Coprococcus, Ruminococcus, Butyricicoccus, and Desulfovibrio were the differential bacteria among the LAB of mice treated with SIs. In addition, acetic acid, valeric acid, isobutyric acid, isovaleric acid, and caproic acid decreased, while butyric acid and propionic acid increased in the mice treated with SIs. Taken together, SIs are beneficial for weight control, even in short-term interventions. The specific mechanism is related to regulating the gut microbiota, changing digestive enzyme activities, and further affecting carbohydrate absorption and metabolism.

Intestinal Microbiomics and Metabolomics Insights into the Hepatoprotective Effects of Lactobacillus paracasei CCFM1222 Against the Acute Liver Injury in Mice.

In recent years, acute liver injury (ALI) has received wide-range attention in the world due to its relatively high morbidity and mortality. This study aimed to explore the hepatoprotective effect of Lactobacillus paracasei CCFM1222 against lipopolysaccharide (LPS)-induced ALI mice and further elaborate its mechanism of action from the perspective of intestinal microbiomics and metabolomics. The results displayed that L. paracasei CCFM1222 pretreatment significantly decreased the serum ALT, and AST levels, inhibited the releases of hepatic TNF-α, IL-1β, and IL-6 levels, and activated the SOD, CAT, and GSH-Px activities in LPS-treated mice. The cecal short-chain fatty acid (SCFAs) levels were increased in LPS-treated mice with L. paracasei CCFM1222 pretreatment. In addition, L. paracasei CCFM1222 pretreatment remarkably shifted the intestinal microbiota composition, including the higher abundance of Faecalibaculum, Bifidobacterium, and lower abundance of the Prevotellaceae NK3B31 group, which is positively associated with the cecal propionic, butyric, valeric, isobutyric, and isovaleric acids. The metabolomics based on UPLC-QTOF/MS revealed that L. paracasei CCFM1222 pretreatment significantly regulated the composition of feces metabolites in LPS-treated mice, especially the potential biomarker-related butanoate metabolism, vitamin B6 metabolism, D-glutamine and D-glutamate metabolism, tryptophan metabolism, caffeine metabolism, arginine biosynthesis, arginine, and proline metabolism. Moreover, L. paracasei CCFM1222 pretreatment remarkably regulated the expression of gene-associated ALI (including Tlr4, Myd88, Nf-kβ, iNOS, Cox2, Iκ-Bα, Nrf2, and Sirt-1). In conclusion, these results suggest the possibility that L. paracasei CCFM1222 supplementation has beneficial effects on preventing the occurrence and development of ALI by inhibiting the inflammatory responses and altering intestinal microbiota composition and their metabolites.

Cultivation of gastrointestinal microbiota in a new growth system revealed dysbiosis and metabolic disruptions in carcinoma-bearing rats.

A challenge in the study of gastrointestinal microbiota (GITm) is the validation of the genomic data with metabolic studies of the microbial communities to understand how the microbial networks work during health and sickness. To gain insights into the metabolism of the GITm, feces from healthy and sick rats with cancer were inoculated in a defined synthetic medium directed for anaerobic prokaryote growth (INC-07 medium). Significant differences between cultures of healthy and sick individuals were found: 1) the consumption of the carbon source and the enzyme activity involved in their catabolism (e.g., sucrase, lactase, lipases, aminotransferases, and dehydrogenases); 2) higher excretion of acetic, propionic, isobutyric, butyric, valeric, and isovaleric acids; 3) methane production; 4) ability to form biofilms; and 5) up to 500 amplicon sequencing variants (ASVs) identified showed different diversity and abundance. Moreover, the bowel inflammation induced by cancer triggered oxidative stress, which correlated with deficient antioxidant machinery (e.g., NADPH-producing enzymes) determined in the GITm cultures from sick individuals in comparison with those from control individuals. Altogether, the data suggested that to preserve the microbial network between bacteria and methanogenic archaea, a complete oxidation of the carbon source may be essential for healthy microbiota. The correlation of 16S rRNA gene metabarcoding between cultures and feces, as well as metabolomic data found in cultures, suggest that INC-07 medium may be a useful tool to understand the metabolism of microbiota under gut conditions.

The mitigative effect of ovotransferrin-derived peptide IQW on DSS-induced colitis via alleviating intestinal injury and reprogramming intestinal microbes.

Inflammatory bowel disease (IBD) is a chronic disease with multiple complications during its development, and it is difficult to cure. The aim of this study was to evaluate the alleviating effect of different concentrations of the bioactive peptide IQW (Ile-Gln-Trp) on dextran sodium sulfate (DSS)-induced colitis in mice. For this study, we randomly divided 56 ICR mice into seven groups: the (I) control (CON), (II) dextran sodium sulfate treatment (2.5% DSS), (III) IQW-DSS (20 μg/ml) treatment, (IV) IQW-DSS (40 μg/ml) treatment, (V) IQW-DSS (60 μg/ml) treatment, (VI) IQW-DSS (80 μg/ml) treatment, and (VII) IQW-DSS (100 μg/ml) groups. The results showed that IQW at 60 μg/ml alleviated body weight loss, improved the liver index (p < 0.05), and improved histomorphological and pathological changes in the colon compared to the DSS-treated group. IQW at 60 μg/ml and IQW at 80 μg/ml modified intestinal microbial disorders. In addition, IQW at 60 μg/ml significantly increased butyric acid levels and decreased valeric acid levels, while IQW at 80 μg/ml significantly increased isobutyric acid and isovaleric acid levels. Hence, IQW at a concentration of 60 μg/ml alleviates DSS-induced colitis by enhancing the body's anti-inflammatory ability and regulating intestinal flora and metabolic changes. In the above context, IQW at 60 μg/ml could be a potential candidate for IBD prevention and treatment.

Dietary silymarin ameliorating reproductive and lactation performance of sows via regulating body antioxidant and metabolism

ObjectiveThe experiment was conducted to explore the effects of silymarin on reproductive and lactation performance, serum antioxidants, and body metabolism of sows. MethodsSixty pregnant sows (85 d, Large × Landrace) with similar genetic background, body condition, and parity were randomly divided into three groups, and each group has 20 individually housed sows. The sows in the control group (CG) were fed with basal diet, and those in the experimental group A (EGA) and B (EGB) were fed with basal diet containing 250 and 500 mg/kg silymarin, respectively. The experiment lasted 46 days from day 85 of gestation to the end of lactation (weaning on day 17 ).The milk composition and serum biochemical parameters were determined by a milk composition analyzer and a blood biochemical analyzer, respectively. Serum antioxidant indexes and plasma hormone levels were measured using the biochemical kits. The gas chromatograph was applied to detect the fecal short chain fatty acids. ResultsCompared with the CG, the total feed intake (TFI) and average daily feed intake (ADFI) were significantly increased (P < 0.01), and the urea content in regular milk tended to increase (P = 0.095) in the EG. The serum malondialdehyde (MDA) contents were decreased on day 90 of gestation and the day of farrowing (P < 0.01), and the serum contents of total antioxidant capacity (T-AOC) tended to increase on day 17 of lactation (P = 0.099) compared with the CG. Compared with the CG, the serum triglyceride (TG) concentrations in the EG tended to increase on day 90 of gestation (P = 0.062), and the content of serum total protein (TP) and albumin (ALB) reduced on day 17 of lactation (P < 0.01). Compared with the CG, plasm D-lactic acid content was decreased (P < 0.05), and the plasma prostaglandin (PG) level tended to increase (P = 0.088) in the EG on the day of farrowing and day 17 of lactation. Compared with the CG, fecal isobutyric acid concentration in the EG significantly decreased on the day of farrowing ( P < 0.05). ConclusionAdding 250 – 500 mg/kg silymarin to diets from the late gestation to the end of lactation could improve reproductive and lactation performance of sows via the regulation of nutrient metabolism and serum antioxidant.

Short-chain fatty acids profiling in biological samples from a mouse model of Sjögren’s syndrome based on derivatized LC-MS/MS assay

An analytical platform is required to characterize the short-chain fatty acids (SCFAs) in a mouse model of pathological immune conditions. Therefore, liquid chromatography tandem mass spectrometry combined with 2-picolylamine derivatization and a comprehensive study of SCFAs distribution based on serum, saliva, feces, liver, and brain from a mouse model of Sjögren’s syndrome (SS) is performed. The design of experiments is used to achieve efficient 2-picolylamine derivatization, and optimize the reaction conditions. Twelve SCFAs are derivatized, and separated on a reversed-phase C18 column. All SCFAs show high linearity (r2 > 0.995) and intra/inter-day accuracy values from 71.6% to 115.6% (precision < 13.7%). This method was used to determine SCFAs concentrations in the serum, saliva, feces, liver, and brain of an SS model mice, and isobutyric acid, valeric acid, isovaleric acid, and 2-methylbutyric acid in liver from SS were significantly different compared with control group. Moreover, the preliminary evaluation of propionic acid, butyric acid, isobutyric acid, valeric acid, and isovaleric acid in saliva is conducted based on the respective SS stages and are correlated with these histological scores. This analytical platform for the widely SCFAs profiling in several tissues can be a clue for studying unclear immune pathophysiology.

Associations of air PM2.5 level with gut microbiota in Chinese Han preschoolers and effect modification by oxytocin receptor gene polymorphism

Variations in the single nucleotide polymorphisms (SNPs) of the oxytocin receptors (OXTR) indicate individual differences in stress response, social behavior, and psychopathology, but very few paper mentioned OXTR as part of the mechanism linking exposure to air pollution and poor social interactions. The authors investigated the moderating role of Oxytocin receptor (OXTR) rs53576 polymorphism in the relationship between PM2.5 level and gut microbiota in children, in an attempt to provide some reference for the evidence linking biological and environmental factors to children brain development. The study included 86 healthy Chinese preschoolers (50 males, 36 females) from two campuses of a kindergarten with different air PM2.5 levels. Atmospheric PM2.5 values released by air quality monitoring stations where the two campuses are located were collected for 30 days. The genotypes of OXTR rs53576 were determined by PCR and restriction fragment length polymorphism. The gut microbiota situation was evaluated by determining urinary concentrations of short-chain fatty acids. Urinary levels of cortisone and cortisol were determined to assess the impact of air pollution on the HPA axis. Urinary 2′-Deoxy-7,8-dihydro-8-oxoguanosine and 8-oxo-7,8-dihydroguanosine were measured to evaluate the oxidative stress state. The genotype distribution frequency of rs53576 polymorphism was consistent with Hardy-Weinberg equilibrium. The average urinary concentrations of cortisone, cortisol and 8-OHdG in high pollution campus preschoolers were significantly higher than those in low pollution campus preschoolers, while situations were opposite for acetic acid, propionic acid, isobutyric acid, butyric acid and valeric acid. The interaction between OXTR rs53576 and air pollution had a significant effect on urinary acetic acid. Allele G of rs53576 may be a risk factor for gut microbiota disorder caused by air pollution, and children with GA/GG genotype may be more susceptible than those with AA genotype.

Insoluble and Soluble Dietary Fibers from Kiwifruit (Actinidia deliciosa) Modify Gut Microbiota to Alleviate High-Fat Diet and Streptozotocin-Induced TYPE 2 Diabetes in Rats.

This study aims to examine the anti-diabetic properties of insoluble and soluble dietary fibers from kiwifruit (KIDF and KSDF) in rats with type 2 diabetes mellitus (T2DM) resulting from a high-fat diet (HFD) and streptozotocin (STZ). Both KIDF and KSDF treatments for four weeks remarkably decreased body weight and increased satiety. In addition, the blood glucose level and circulatory lipopolysaccharide (LPS) content were decreased, while the insulin resistance, inflammatory status, and lipid profiles improved. These anti-diabetic effects might be related to the regulation of gut microbiota and increased SCFA content. The key microbial communities of KIDF and KSDF were different. Furthermore, the KIDF treatment increased the level of total SCFAs and isobutyric acid, while KSDF increased the levels of total SCFAs and butyric acid. The association between critical species and SCFA and between SCFA and biochemical parameters indicated that the mechanisms of KIDF and KSDF on T2DM might be different.

The effect of vegetable and animal oils added to different forages and concentrates on the in vitro fermentation parameters in ruminants

ABSTRACT This study aimed to determine the effects of fermentation parameters of sunflower oil, vegetable oil blend, palm oil and chicken oil addition to sunflower meal, wheat grain, alfalfa herbage and corn silage at different rates (4% and 6%, dry matter basis). The oil supplementation up to 6% rate to the alfalfa herbage and corn silage did not adversely affect the level of in vitro gas production, metabolic energy (ME), net energy lactation (NEL), organic matter digestion (OMD) and molarities of acetic, propionic, butyric, iso-valeric, iso-butyric and valeric acids and number of total protozoa (P > 0.05). The oil supplementation to alfalfa herbage increased molarities of butyric, iso-valeric, iso-butyric and valeric acids and number of total protozoa (except sunflower oil) in rumen fluid (P < 0.05). Palm oil decreased the in vitro gas production, ME, NEL and OMD values of sunflower meal (P < 0.05). Supplementation of vegetable oil blend to wheat grain increased ME, NEL and OMD values and butyric acid molarity in rumen fluid (P < 0.05). The in vitro ruminal ammonia–nitrogen concentrations of alfalfa herbage and corn silage increased by vegetable oil blend, palm oil and chicken oil up to 6% (P < 0.05). As a result, the nutrient content of the feedstuffs used changed the in vitro ruminal fermentation values of the oil additive to be added. The addition of sunflower oil, vegetable oil blend, palm oil and chicken oil at 4% and 6% rates to corn silage, alfalfa herbage, sunflower meal and wheat grain feed found to differ on in vitro ruminal fermentation parameters.

Rumen fluid preservation for in vitro gas production systems

Preservation of rumen fluid is a potential approach to standardize in vitro studies while minimizing the cost of maintaining donor animals, variations in the rumen fluid collection procedure, and ethical issues. Using a batch gas production system, the present experiment evaluated a series of rumen fluid preservation techniques for their use in in-vitro feed fermentation. A factorial design was used to compare two substrates (lucerne hay vs. wheat grain) and four preservation techniques relative to fresh rumen fluid: (1) Frozen at − 20 ⁰C, (2) Preserved using 5 % dimethyl sulfoxide (DMSO) and frozen at − 20 ⁰C (D-20 ⁰C), 3) snap-frozen using liquid Nitrogen and stored at − 80 ⁰C (− 80 ⁰C), and 4) preserved using 5 % DMSO, snap frozen in liquid Nitrogen and stored at − 80 ⁰C (D-80 ⁰C), over five incubation periods (1, 4, 8, 14 and 30 days). The mean cumulative gas production of wheat grain (84.5 ml/g) and lucerne hay (54.9 ml/g) incubated with fresh rumen fluid did not differ (P > 0.05) from the gas production using rumen fluid preserved with D-20 ⁰C, 90.1 ml/g and 55.0 ml/g respectively. The maximum gas production from fresh rumen fluid (87.6 ml/g) was also not different (P > 0.05) from rumen fluid preserved with D-20 ⁰C (85.3 ml/g). The concentration of acetic acid, propionic acid, and isobutyric acid did not differ (P < 0.001) between fresh rumen fluid and the D-20 ⁰C. Incubated substrates produced higher average ammonia-N values (P > 0.05) when fermented with fresh rumen fluid compared to a preserved rumen fluid, except for − 80 ⁰C. The rumen fluid stored under D-20⁰C produced gas production results with the least difference to fresh rumen fluid and would be a more reliable preservation technique to adopt than the other methods evaluated.

Relationship between rumen microbial differences and traits among Hu sheep, Tan sheep, and Dorper sheep.

Rumen microbes play an important role in the growth and development of ruminants. Differences in variety will affect the rumen community structure. The three excellent sheep breeds were selected for this study (Hu sheep, Tan sheep, and Dorper sheep) have different uses and origins. The sheep were raised on the same diet to 180 d of age in a consistent environment. 16S rDNA V3 to V4 region sequencing was used to assess the rumen microbes of 180 individuals (60 per breed). There were differences in microbial diversity among different sheep breeds (P < 0.05). Principal coordinate analysis showed that the three varieties were separated, but also partially overlapped. Linear discriminant analysis effect size identified a total of 19 biomarkers in three breeds. Of these biomarkers, five in Hu sheep were significantly negatively correlated with average feed conversion rate (P < 0.05). Six biomarkers were identified in the rumen of Dorper sheep, among which Ruminococcus was significantly positively correlated with body weight at 80 d (P < 0.05). In Tan sheep, Rikenellaceae_RC9_gut_group was significantly positively correlated with meat fat, and significantly positively correlated with volatile fatty acids (VFAs), such as butyric acid and isobutyric acid (P < 0.05). The Rikenellaceae_RC9_gut_group may regulate Tan mutton fat deposition by affecting the concentration of VFAs. Functional prediction revealed enrichment differences of functional pathways among different sheep breeds were small. All were enriched in functions, such as fermentation and chemoheterotrophy. The results show that there are differences in the rumen microorganisms of the different sheep breeds, and that the microorganisms influence the host.

Characterisation of the key volatile compounds of commercial Gouda cheeses and their contribution to aromas according to Chinese consumers' preferences.

A systematic flavoromics-based analysis of samples of 12 commercially available Gouda cheeses was performed to determine their key volatile components, the contribution of these components to the aromas of the cheeses, and which aromas were preferred by a panel of Chinese consumers. The sensory analysis results show that the Chinese consumers preferred young and medium cheeses, and that sensory attributes such as 'milk' and 'cream' were the most popular. Seventy-seven aroma compounds were identified by gas chromatography-mass spectrometry, and 28 of these were determined to be aroma-active compounds by gas chromatography-olfactometry analysis and calculation of their odour activity values. Partial least-squares analysis revealed that compounds such as diacetyl and acetoin correlated with aromas preferred by the Chinese consumers, while isobutyric acid, hexanoic acid and valeric acid correlated with aromas disliked by the Chinese consumers. Finally, the flavour contribution of each aroma-active compound was validated through aroma reorganisation and omission experiments.

Characteristics of ruminal microbiota and metabolome in Holstein cows differing in milk protein concentrations.

The rumen is a vital organ containing vast amounts of microbes that play a key role in the digestion of nutrients and affect the production performance of ruminants. However, few studies have focused on the characterization of the ruminal microbiota composition and function in cows with long-term difference milk protein concentrations, and the relationship between milk protein concentration and ruminal microbiota remains elusive. In this study, we collected the data of milk protein concentrations of 1,025 Holstein cows for 10 mo on a commercial farm. Based on the milk protein concentrations, 30 cows were selected and divided into three groups (n = 10 per group): low milk protein group (LMP, milk protein concentration < 3.1%), medium milk protein group (MMP, 3.1% ≤ milk protein concentration < 3.4%), and high milk protein group (HMP, milk protein concentration ≥ 3.4%). The ruminal microbiome, metabolome, VFA concentrations and proportions, and amino acid profiles of the three groups were analyzed. The data showed that free amino acid (FAA) levels were lower in the rumen and higher in the plasma of HMP cows (P < 0.05). In addition, lower NH3 concentrations were observed in the rumen, plasma, and milk of the HMP cows (P < 0.05). Protease activity and isobutyric acid molar proportion in the rumen were lower in the HMP group (P < 0.05). Microbiome analysis showed that HMP cows had lower microbial diversity (represented as Shannon and Simpson indices) than LMP cows. At the genus level, lower relative abundances of Prevotella_1 and Ruminococcaceae_UCG_005 were observed in the HMP group (P < 0.05). At the operational taxonomic unit (OTU) level, a lower relative abundance of OTU3 (Prevotella ruminicola) was observed in the HMP group (P < 0.05). We found that the relative abundances of ruminal Prevotella_1 and OTU3 (Prevotella ruminicola) were negatively correlated with milk protein concentration (P < 0.05). These findings suggested that the cows with long-term high milk protein concentrations had lower microbial diversity and weaker protein degradation ability in the rumen. Furthermore, our observations identified a correlation between the milk protein concentration and ruminal microbiota.

Effects of fumaric and maleic acids on the fermentation, nutrient composition, proteolysis and in vitro ruminal gas of corn silage

AbstractThe study aimed to determine the effect of fumaric and maleic acids on the ensiling process. The corn herbage was ensiled without additives (control silage) or with 0.25% fumaric acid (FA25), 0.50% fumaric acid (FA50), 0.25% maleic acid (MA25), 0.50% maleic acid (MA50), FA25 + MA25 (FA25MA25) and FA50 + MA50 (FA50MA50) (treatment silages) as wet basis. The starch contents of FA50 and MA50 silages were lower than the content of the control silage (p &lt; .05). The lactic acid content of the FA50MA50 silage was lower than that of the control silage (p &lt; .05). Percentages of linoleic acid of MA25 and MA50 silages were higher than that of the FA50 silage (p &lt; .05). The in vitro methane production and metabolic energy (ME) value of FA50MA50 silage was lower than that of the control silage (p &lt; .05). The in vitro organic matter digestion (OMD) values of FA25, MA25 and FA50MA50 silages were lower than that of control silage (p &lt; .05). The molarities of acetic (AA), propionic (PA), butyric (BA), isovaleric (IVA), isobutyric (IBA) and total volatile fatty (TVFA) acids of the in vitro ruminal fermentation fluid for the FA50MA50 silage were lower than that of the control silage (p &lt; .05). As a result, the addition of fumaric and maleic acids (0.25% alone and together, or 0.5% alone) in ensiling of corn herbage did not change the quality, acidity (except for propionic, butyric and isobutyric acids) and nutrient contents (except for non‐fiber carbohydrates and starch) and in vitro ruminal fermentation values (gas–methane production and organic acids). The combined use of 0.5% fumaric plus 0.5% maleic acid harmed silage quality and in vitro ruminal fermentation values. However, 0.5% maleic acid was partially more effective than those other organic acid additions in preserving linoleic and α‐linolenic acids in the silage material.

A preliminary study on preparation, characterization, and prebiotic activity of a polysaccharide from the edible mushroom Ramaria flava.

Polysaccharides derived from edible mushrooms were sources of new prebiotic compounds. Limited studies of their prebiotic effects, as well as the presence of residual dark colors, impede their use as prebiotics in the food industry. To boost the prebiotic value of polysaccharides from the edible mushroom Ramaria flava, a decolorization method, and the physicochemical characterization and prebiotic potential of the decolorized polysaccharide (DRFP) were investigated in this study. The reversed micelle system consisting of n-hexanol/isooctane (3:7, v/v) and 200 mM surfactant (CTAB) was an appropriate decolorized method for R. flava crude polysaccharide. That decolorized polysaccharide was 101.68 kDa and contained glucose, galactose, mannose, fucose, xylose, rhamnose, arabinose, and glucuronic acid in a ratio of 40.61:26.97:17.72:7.78:6.31:0.11:0.06:0.44. Furthermore, DRFP exhibited typical shear-thinning behavior and possessed good thermal stability. And 98.76% of DRFP was allowed to transit through the oral cavity and gastrointestinal tract nearly indigestibly in vitro fermentation. It also revealed a prebiotic availability through stimulating Lactobacillus rhamnosus proliferation and inducing enterocoel acidification. When utilized as a carbon source, DRFP significantly improves the production of short-chain fatty acids by L. rhamnosus, particularly acetic, propionic, isobutyric, and hexanoic acids. Therefore, this work suggests the further application of R. flava polysaccharides as emerging prebiotics, which may be used as an ingredient in functional food and nutraceutical products. PRACTICAL APPLICATIONS: Prebiotics could regulate gut microbial community and are closely associated with host health. This work reported that a decolorized polysaccharide (DRFP) prepared from the edible mushroom Ramaria flava was indigestible and could improve Lactobacillus rhamnosus proliferation and short-chain fatty acid production, which could provide useful information for the application of DRFP as a prebiotic additive in the food industry.

Effect of ancient wheat pasta on gut microbiota composition and bacteria-derived metabolites: A randomized controlled trial.

Background and aimIn recent years, many studies have suggested that ancient wheat products might have beneficial effects on cardiometabolic risk profile, but little is known about their effect on gut microbiota (GM). The aim of the present study was to evaluate whether a replacement diet with pasta made from ancient wheat (AD) could influence the GM composition and its metabolites’ production compared to a replacement diet with pasta made from modern wheat (CD).MethodsA randomized, double-blinded crossover trial with two intervention phases was conducted on 20 clinically healthy adults (9 females; 11 males; mean age 43.1 ± 12.5 years). Study participants were assigned to consume pasta made using semi-whole flour from organic wheat that was either from ancient or modern control wheat for 8 weeks in a random order. An 8-week washout period was implemented between the interventions. Stool samples were collected from all subjects at the beginning and at the end of each intervention period. GM composition, and short- (SCFAs) and medium- chain fatty acids (MCFAs) production was evaluated.ResultsDietary interventions did not produce significant diversity in the GM composition at higher ranks (phylum, class, order and family), but only at genus level. In detail, the AD significantly (adj. p < 0.05) changed the abundance of Erysipelatoclostridium spp., Bacteroides_pectinophilus_group spp., CAG-873 spp., and Holdemanella spp. The CD significantly affected the abundance of Akkermansia spp., CAG-873 spp., Hungatella spp., Lachnospiraceae_UCG-008 spp., NK4A214_group spp., Frisingicoccus spp., Megasphaera spp., Synergistes spp., and Tyzzerella spp. Regarding the production of SCFAs and MCFAs, AD resulted in a significant increase of fecal acetic (+0.7%), isobutyric (+30.1%), 2-methylbutyric (+64.2%), and isovaleric (+22.5%) acids. On the other hand, CD resulted in increased levels of isobutyric (+71.4%), 2-methylbutyric (+116.2%), isovaleric (+99%), and valeric (+21.4%) acids, and a reduction of butyric (-31.6%) and hexanoic (-66.4%) acids.ConclusionA short-term replacement diet with both ancient and modern wheat pasta determined significant changes in GM composition at the genus level but notably the AD resulted in a greater beneficial impact on anti-inflammatory SCFAs.

L-norvaline affects the proliferation of breast cancer cells based on the microbiome and metabolome analysis.

The altered faecal metabolites and microbiota might be involved in the development of breast cancer. We aimed to investigate the effect of differential metabolites on the proliferative activity of breast cancer cells. We collected faecal samples from 14 breast cancer patients and 14 healthy subjects. Untargeted metabolomics analysis, short-chain fatty acid (SCFA) targeted analysis, and 16S rDNA sequencing was performed. The gut metabolite composition of patients changed significantly. Levels of norvaline, glucuronate and galacturonate were lower in the cancer group than in the Control (p < 0.05). 4-Methylcatechol and guaiacol increased (p < 0.05). Acetic acid and butyric acid were lower in the cancer group than in the control group (p < 0.05). Isobutyric acid and pentanoic acid were higher in the cancer group than in the control (p < 0.05). In the genus, the abundance of Rothia and Actinomyces increased in the cancer group, compared with the control group (p < 0.05). The differential microbiotas were clearly associated with differential metabolites but weakly with SCFAs. The abundance of Rothia and Actinomyces was markedly positively correlated with 4-methylcatechol and guaiacol (p < 0.05) and negatively correlated with norvaline (p < 0.05). L-norvaline inhibited the content of Arg-1 in a concentration-dependent manner. Compared with the L-norvaline or doxorubicin hydrochloride (DOX) group, the proliferation abilities of 4T1 cells were the lowest in the L-norvaline combined with DOX (p < 0.05). The apoptosis rate increased (p < 0.05). Faecal metabolites and microbiota were significantly altered in breast cancer. Levels of differential metabolites (i.e. Norvaline) were significantly correlated with the abundance of differential microbiota. L-norvaline combined with DOX could clearly inhibit the proliferation activity of breast cancer cells. This might provide clues to uncover potential biomarkers for breast cancer diagnosis and treatment.