Using sentinel-2 satellite images and machine learning algorithms to predict tropical pasture forage mass, crude protein, and fiber content.

Grasslands cover approximately 24% of the Earth's surface and are the main feed source for cattle and other ruminants. Sustainable and efficient grazing systems require regular monitoring of the quantity and nutritive value of pastures. This study demonstrates the potential of estimating pasture leaf forage mass (FM), crude protein (CP) and fiber content of tropical pastures using Sentinel-2 satellite images and machine learning algorithms. Field datasets and satellite images were assessed from an experimental area of Marandu palisade grass (Urochloa brizantha sny. Brachiaria brizantha) pastures, with or without nitrogen fertilization, and managed under continuous stocking during the pasture growing season from 2016 to 2020. Models based on support vector regression (SVR) and random forest (RF) machine-learning algorithms were developed using meteorological data, spectral reflectance, and vegetation indices (VI) as input features. In general, SVR slightly outperformed the RF models. The best predictive models to estimate FM were those with VI combined with meteorological data. For CP and fiber content, the best predictions were achieved using a combination of spectral bands and meteorological data, resulting in R2 of 0.66 and 0.57, and RMSPE of 0.03 and 0.04 g/g dry matter. Our results have promising potential to improve precision feeding technologies and decision support tools for efficient grazing management.

Effects of dietary forage neutral detergent fiber and rumen degradable starch ratios on chewing activity, ruminal fermentation, ruminal microbes and nutrient digestibility of Hu sheep fed a pelleted total mixed ration.

Pelleted total mixed ration (P-TMR) feeding, which has become a common practice in providing nutrition for fattening sheep, requires careful consideration of the balance between forage neutral detergent fiber (FNDF) and rumen degradable starch (RDS) to maintain proper rumen functions. The present study aimed to investigate the effects of the dietary FNDF/RDS ratio (FRR) on chewing activity, ruminal fermentation, ruminal microbes, and nutrient digestibility in Hu sheep fed a P-TMR diet. This study utilized eight ruminally cannulated male Hu sheep, following a 4 × 4 Latin square design with 31 d each period. Diets consisted of four FRR levels: 1.0 (high FNDF/RDS ratio, HFRR), 0.8 (middle high FNDF/RDS ratio, MHFRR), 0.6 (middle low FNDF/RDS ratio, MLFRR), and 0.4 (low FNDF/RDS ratio, LFRR). Reducing the dietary FRR levels resulted in a linear decrease in ruminal minimum pH and mean pH, while linearly increasing the duration and area of pH below 5.8 and 5.6, as well as the acidosis index. Sheep in the HFRR and MHFRR groups did not experience subacute ruminal acidosis (SARA), whereas sheep in another two groups did. The concentration of total volatile fatty acid and the molar ratios of propionate and valerate, as well as the concentrate of lactate in the rumen linearly increased with reducing dietary FRR, while the molar ratio of acetate and acetate to propionate ratio linearly decreased. The degradability of NDF and ADF for alfalfa hay has a quadratic response with reducing the dietary FRR. The apparent digestibility of dry matter, organic matter, neutral detergent fiber, and acid detergent fiber linearly decreased when the dietary FRR was reduced. In addition, reducing the dietary FRR caused a linear decrease in OTUs, Chao1, and Ace index of ruminal microflora. Reducing FRR in the diet increased the percentage of reads assigned as Firmicutes, but it decreased the percentage of reads assigned as Bacteroidetes in the rumen. At genus level, the percentage of reads assigned as Prevotella, Ruminococcus, Succinivibrio, and Butyrivibrio linearly decreased when the dietary FRR was reduced. The results of this study demonstrate that the dietary FRR of 0.8 is crucial in preventing the onset of SARA and promotes an enhanced richness of ruminal microbes and also improves fiber digestibility, which is a recommended dietary FRR reference when formulating P-TMR diets for sheep.

Forage neutral detergent fiber (FNDF) and rumen degradable starch (RDS) are key components of carbohydrates in the diet for ruminants, which would reflect saliva secretion and the acid production potential of feed. However, appropriate FNDF to RDS ratios (FRR) applicable to ruminants under the condition of pelleted total mixed ration (P-TMR) feeding have not been reported. In this study, we investigated the effects of the dietary FRR on chewing activity, ruminal fermentation, ruminal microbial communities, and nutrient digestibility of Hu sheep under P-TMR feeding. The results indicate that reducing dietary FRR levels would induce acidosis in sheep, which negatively affected fiber utilization and ruminal bacterial communities. The FRR of 0.8 was a recommended dietary FRR when formulating a P-TMR diet for fattening sheep, as indicated by decreased ruminal acidosis risk and increased richness of ruminal microbes in the rumen as well as nutrient digestibility.

Inclusion of chia seeds (Salvia hispanica L.) and pumpkin seeds (Cucurbita moschata) in dairy sheep diets.

Chia (Salvia hispanica L.) seed (CS) and Pumpkin (Cucurbita moschata) seed (PS) are used in ruminant diets as energy sources. The current experiment studied the impact of dietary inclusion of CS and PS on nutrient intake and digestibility, milk yield, and milk composition of dairy sheep. Twelve primiparous Texel × Suffolk ewes [70 ± 5 days in milk (DIM); 0.320 ± 0.029 kg milk yield] were distributed in a 4 × 3 Latin square design and fed either a butter-based control diet [CON; 13 g/kg dry matter] or two diets with 61 g/kg DM of either CS or PS. Dietary inclusion of CS and PS did not alter live weight (p >0.1) and DM intake (p >0.1). However, compared to the CON, dietary inclusion of both CS and PS increased the digestibility of neutral detergent fiber (p <0.001) and acid detergent lignin (p < 0.001). Milk production (p = 0.001), fat-corrected milk (p < 0.001), and feed efficiency (p < 0.001) were enhanced with PS, while the highest milk protein yield (p < 0.05) and lactose yield (p < 0.001) were for CS-fed ewes. Compared to the CON diet, the ingestion of either CS and/or PS decreased (p < 0.001) the C16:0 in milk. Moreover, both CS and PS tended to enhance the content of C18:3n6 (p > 0.05) and C18:3n3 (p > 0.05). Overall short-term feeding of CS and/or PS (up to 6.1% DM of diet) not only maintains the production performance and digestibility of nutrients but also positively modifies the milk FA composition.

Mannan-oligosaccharides promote gut microecological recovery after antibiotic disturbance.

Antibiotic treatment often causes collateral damage to the gut microbiota, including changes in its diversity and composition. Dietary fiber helps maintain intestinal health, regulate short-chain fatty acids, and promote the recovery of the intestinal microbiome. However, it is currently unknown which specific plant-based dietary fiber is optimal as a dietary supplement for restoring the intestinal microbiota after antibiotic disturbance. Previously, we proposed predictive recovery-associated bacterial species (p-RABs) and identified the most important interventions. This study aimed to identify an optimal form of dietary fiber to recover the gut microbiome after antibiotic treatment. Therefore, we examined the types of dietary fibers associated with p-RABs through a p-RAB-metabolite bilayer network constructed from prior knowledge; we searched for dietary fiber that could provide nutritional support for Akkermansia muciniphila and Bacteroides uniformis. C57BL/6J mice were fed with 500 mg kg-1 of different types of dietary fibers daily for one week after being treated with ampicillin. The results showed that mannan-oligosaccharides could better promote the diversity of intestinal microbial growth, enhance the recovery of most genera, including Akkermansia and Bacteroides, and inhibit certain pathogenic bacteria, such as Proteus, compared to the other fiber types. Furthermore, mannan-oligosaccharides could regulate the levels of short-chain fatty acids, especially butyric acid. Functional predictions showed that starch metabolism, galactose metabolism, and the metabolism of other carbohydrates played key roles in the early recovery process. In conclusion, mannan-oligosaccharides could enhance the recovery of the intestinal microbiome after antibiotic treatment, offering valuable insights for targeted dietary strategies.

Effects of pectin methyl-esterification on intestinal microbiota and its immunomodulatory properties in naive mice.

Pectins are dietary fibers that are attributed with several beneficial immunomodulatory effects. Depending on the degree of esterification (DE), pectins can be classified as high methoxyl pectin (HMP) or low methoxyl pectin (LMP). The aim of this study was to investigate the effects of pectin methyl-esterification on intestinal microbiota and its immunomodulatory properties in naive mice. Supplementation of the diet with LMP or HMP induced changes in the composition of the intestinal microbiota in mice toward Bacteroides, which was mainly promoted by HMP. Metabolome analysis of stool samples from pectin-fed mice showed a different effect of the two types of pectin on the levels of short-chain fatty acids and bile acids, which was consistent with highly efficient in vivo fermentation of LMP. Analysis of serum antibody levels showed a significant increase in IgG and IgA levels by both pectins, while FACS analysis revealed a decrease of infiltrating inflammatory cells in the intestinal lamina propria by HMP. Our study revealed that the structural properties of the investigated pectins determine fermentability, effects on microbial composition, metabolite production, and modulation of immune responses. Consumption of HMP preferentially altered the gut microbiota and suppressed pro-inflammatory immune responses, suggesting a beneficial role in inflammatory diseases.

Ruminal degradation characteristics of bagasse with different fermentation treatments in the rumen of beef cattle.

This experiment aimed to study the degradation characteristics of bagasse after three fermentation treatments in beef cattle. Bagasse 1 was treated with 0.3% lactic acid bacteria (w/w). Bagasse 2 was treated with 0.3% mixed strains (Saccharomyces cerevisiae, Aspergillus niger, Aspergillus oryzae, and lactic acid bacteria at 2:1:1:1). Bagasse 3 was treated with 0.1% cellulase and 0.1% xylanase in addition to 0.3% mixed strains of bagasse 2. The dry matter (DM), crude ash (ASH), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) in the bagasses were determined. Compared to the control bagasse (without the strain and enzyme treatments), three fermented bagasses showed higher DM after 4 h fermentation. The CP and ASH contents in fermented bagasse 3 were the highest, while the contents of NDF and ADF in fermented bagasse 3 were the lowest among all the groups. The effective degradability of DM, CP, NDF, and ADF was highest in fermented bagasse 3 among the evaluated bagasse feed, followed by fermented bagasse 2 > fermented bagasse 1 > bagasse. Overall, fermented bagasse 3 was better than the control and other treated bagasses, thus fermented bagasse 3 is a hopeful source for ruminant diet of beef cattle.

Cryptic diversity of cellulose-degrading gut bacteria in industrialized humans.

Humans, like all mammals, depend on the gut microbiome for digestion of cellulose, the main component of plant fiber. However, evidence for cellulose fermentation in the human gut is scarce. We have identified ruminococcal species in the gut microbiota of human populations that assemble functional multienzymatic cellulosome structures capable of degrading plant cell wall polysaccharides. One of these species, which is strongly associated with humans, likely originated in the ruminant gut and was subsequently transferred to the human gut, potentially during domestication where it underwent diversification and diet-related adaptation through the acquisition of genes from other gut microbes. Collectively, these species are abundant and widespread among ancient humans, hunter-gatherers, and rural populations but are rare in populations from industrialized societies thus indicating potential disappearance in response to the westernized lifestyle.

Effects of Dietary Fiber on Short Chain Fatty Acid Receptor mRNA in Microglia and Serotonergic Neurons in the Mouse Brain.

Short-chain fatty acids (SCFAs) are bioactive lipids that are released into the colon as a metabolite of bacterial fermentation of dietary fibers. Beyond their function in the gastrointestinal tract, SCFAs can also have effects inthe brain, as a part of the gut-brain axis. Recent investigations into potential therapeutic interventions via the manipulation of the gut microbiome-and thus their SCFA metabolites-has been emerging as a new branch of personalized medicine,especially for mental health conditions. The current study sought to measure and localize SCFA receptors in the mouse brain. Two cell types have been implicated in the gut-brain axis: microglia and serotonergic neurons. We used fluorescentin situhybridization in brain sections from mice fed diets with different compositions of fat and fiber to quantify the mRNA levels of known gene markers of these two cell types and colocalize each with mRNA for free fatty acid receptors that bind SCFAs. We focused onmicroglia in the hippocampus and the serotonergic neurons of the dorsal raphe. We found high colocalization of SCFA receptors in both microglia and serotonergic neurons and discovered that SCFA receptor expression in the dorsal raphe is driven by fiber solubility, while SCFA receptor expression in the hippocampus is driven by fiber amount. Higher dietary fiber was associated with decreased tyrosine hydroxylase expression. Thus, our results indicate that the amount and solubility of dietary fiber can change gene expression in the brain's microglia and serotonin neurons, potentially via sensitivity to circulating levels of SCFAs produced in the gut.

Nutritional strategies, performance, digestibility, and carcass traits of Santa Ines and Rabo Largo breeds in a tropical climate.

The aim of this study was to compare the performance, intake, digestibility, ruminal parameters, carcass traits, and the yield of commercial cuts of Santa Ines (SI) and Rabo Largo (RL) breeds fed diets with high or low roughage-to-concentrate ratio (R:C) under a tropical climate. Twenty lambs from each breed were individually housed in covered pens and fed the experimental diets for 58 days. The diets were formulated to meet the growth requirements of lambs with a roughage-to-concentrate ratio of 70:30 and 30:70. Significant interactions of breed × diet for nutrient intake were observed (P < 0.05), with SI lambs fed low R:C diet showing higher intake of dry matter, organic matter, crude protein, and total carbohydrates compared to RL lambs fed the same diet. SI lambs fed high R:C diet had higher intake of neutral detergent fiber than RL lambs (P < 0.05). SI lambs displayed better average daily gain and feed efficiency, regardless of diet (P < 0.05). Carcass traits and gastrointestinal components were influenced by breed and diet (P < 0.05). SI lambs fed low R:C diet showed higher subcutaneous fat thickness and better carcass finishing compared to RL lambs (P < 0.05). SI breed lambs exhibited better growth performance, carcass traits, and gastrointestinal characteristics, even when fed diets with a high roughage-to-concentrate ratio.

Caenorhabditis elegans endorse bacterial nanocellulose fibers as functional dietary Fiber reducing lipid markers.

Bacterial nanocellulose (BNC) is a promising dietary fiber with potential as a functional food additive. We evaluated BNC fibers (BNCf) in the Caenorhabditis elegans model to obtain insight into the BNCf's biointeraction with its gastrointestinal tract while reducing the variables of higher complex animals. BNCf were uptaken and excreted by worms without crossing the intestinal barrier, confirming its biosafety regarding survival rate, reproduction, and aging for concentrations up to 34 µg/ml BNCf. However, a slight decrease in the worms' length was detected. A possible nutrient shortage or stress produced by BNCf was discarded by measuring stress and chemotactic response pathways. Besides, we detected a lipid-lowering effect of BNCf in N2 C. elegans in normal and high-caloric diets. Oxidative damage was computed in N2 worms and Rac1/ced-10 mutants. The GTPase Rac1 is involved in neurological diseases, where its dysregulation enhances ROS production and neuronal damage. BNCf reduced the lipid oxidative markers produced by ROS species in this worm strain. Finally, we detected that BNCf activated the genetic expression of the immunological response and lipid catabolic process. These results strengthen the use of BNCf as a functional dietary fiber and encourage the potential treatment of neurological disease by modulating diet.

Different influences of dietary fiber from various sources on the in vitro digestibility of casein as uncovered by the study of protein-dietary fiber interactions.

How different dietary fibers including pectin, cellulose and lignin affect casein digestibility was studied using in vitro static protocols. Peptides' profile, free amino acids (AAs) content, casein-DF interactions and their influences on enzymatic activities of proteolytic enzymes were studied using combined techniques. Under gastric and intestinal digestive conditions, while pectin could reduce casein digestibility (with an averaged decrease of 12.15% and 7.83, respectively) through both depletion flocculation and hydrogen-binding interactions, lignin inhibited the digestion of casein straightly through reducing the enzymatic activity of proteolytic enzymes, thereby altering the production of free AAs. Although cellulose showed the least detrimental effects, it still significantly reduced the content of Thr, Glu, Val, Leu, Phe, Lys, and no Arg was released. Deeper insight into casein-DF interactions and their influences on casein digestibility improves the development of more effective forms of DF for improving AA homeostasis in individuals.

Integration of subcritical water extraction and treatment with xylanases and feruloyl esterases maximises release of feruloylated arabinoxylans from wheat bran.

Wheat bran is an abundant and low valued agricultural feedstock rich in valuable biomolecules as arabinoxylans (AX) and ferulic acid with important functional and biological properties. An integrated bioprocess combining subcritical water extraction (SWE) and enzymatic treatments has been developed for maximised recovery of feruloylated arabinoxylans and oligosaccharides from wheat bran. A minimal enzymatic cocktail was developed combining one xylanase from different glycosyl hydrolase families and a feruloyl esterase. The incorporation of xylanolytic enzymes in the integrated SWE bioprocess increased the AX yields up to 75%, higher than traditional alkaline extraction, and SWE or enzymatic treatment alone. The process isolated AX with tailored molecular structures in terms of substitution, molar mass, and ferulic acid, which can be used for structural biomedical applications, food ingredients and prebiotics. This study demonstrates the use of hydrothermal and enzyme technologies for upcycling agricultural side streams into functional bioproducts, contributing to a circular food system.

Study on the Digestive Behavior of Chlorogenic Acid in Biomimetic Dietary Fiber and the Antioxidative Synergistic Effect of Polysaccharides and Chlorogenic Acid.

Chlorogenic acid (CA) is often combined with dietary fiber polysaccharides in plant foods, which may affect its digestive behavior and antioxidant activity. This study constructed a biomimetic dietary fiber (BDF) model by combining bacterial cellulose (BC) and pectin with CA and investigated the digestive behavior of CA in BDF. Additionally, the study examined the interaction and synergistic effects of polysaccharides and CA against oxidation. Results showed that BDF and natural dietary fiber had similar microstructures, group properties, and crystallization properties, and polysaccharides in BDF were bound to CA. After simulated gastrointestinal digestion, 41.03% of the CA existed in a conjugated form, and it was possibly influenced by the interaction between polysaccharides and CA. And the release of CA during simulated digestion potentially involved four mechanisms, including the disintegration of polysaccharide-CA complex, the dissolution of pectin, escape from BC-pectin (BCP) network structure, and diffusion release. And polysaccharides and CA may be combined through noncovalent interactions such as hydrogen bonding, van der Waals force, or electrostatic interaction force. Meanwhile, polysaccharides-CA combination had a synergistic antioxidant effect by the results of free-radical scavenging experiments, it was probably related to the interaction between polysaccharides and CA. The completion of this work has a positive significance for the development of dietary intervention strategies for oxidative damage.

Dietary fibre fractions rich in (poly)phenols from orange by-products and their metabolisation by in vitro digestion and colonic fermentation.

Orange peel is an interesting by-product because of its composition, particularly its dietary fibre and flavanones. The aim of this work was to extract different fibre fractions from orange peel to obtain potential added-value ingredients and evaluate how the presence of fibre may interfere with (poly)phenol metabolism. Using an aqueous extraction, as a green extraction method, an insoluble fibre fraction (IFF) and a water-soluble extract (WSE) were obtained. Those fractions were analysed to determine the proximate and dietary fibre composition, hydration properties, (poly)phenol composition and antioxidant capacity, comparing the results with the orange peel (OP). The IFF presented the highest content of insoluble dietary fibre and the WSE showed the highest content of (poly)phenols, these being mainly flavanones. An in vitro faecal fermentation was carried out to evaluate the production of short-chain fatty acids (SCFAs) and lactate as prebiotic indicators; the IFF gave the highest production, derived from the greater presence of dietary fibre. Moreover, catabolites from (poly)phenol metabolism were also analysed, phenylpropanoic acids being the major ones, followed by phenylacetic acids and benzoic acids. These catabolites were found in higher quantities in WSE, because of the greater presence of (poly)phenols in its composition. IFF also showed a significant production of these catabolites, which was delayed by the greater presence of fibre. These results reveal that the new ingredients, obtained by an environmentally friendly water extraction procedure, could be used for the development of new foods with enhanced nutritional and healthy properties.

Interactive effects of a stimbiotic supplementation and wheat bran inclusion in corn- or wheat-based diets on growth performance, ileal digestibility, and expression of nutrient transporters of broilers chickens.

A 42-day experiment was conducted to investigate the interactive effects of a stimbiotic (STB) and wheat bran (WB) in broiler chickens receiving diets (DT) based on corn or wheat. A total of 960 Cobb 500 male broiler chicks at zero-day old were allocated to 64 pens with 8 treatments, 8 replicates per treatment, and 15 birds per replicate. The treatments were arranged in a randomized complete block design with 2 × 2 × 2 factorial, with the factors as diet (corn-soybean meal or wheat-soybean meal), STB (with or without), and WB (0 or 50 g/kg). Body weight gain (BWG), feed intake (FI), and mortality-corrected FCR data were collected for the starter (d 0-10), grower (d 10-28), and finisher (d 28-42) phases. Ileal digesta and jejunal tissue were collected on d 18 and 42. Data were analyzed as a 2 × 2 × 2 factorial using a mixed model of JMP. There was no significant 3-way interaction for growth performance and expression of nutrient transporters. There was a significant SB × WB for FCR (P < 0.05) in the grower phase. Stimbiotic supplementation and WB inclusion individually improved (P < 0.05) FCR regardless of cereal type, but this effect was not observed when the two were combined. In the overall phase (d 0-42), birds receiving corn-based diets had higher (P < 0.05) FI and BWG than those receiving wheat-based diets. There was a significant 3-way interaction for ileal digestible energy (IDE) (P < 0.05) and N digestibility (ND) on d 18 and 42 (P < 0.05). There was no effect of STB or WB in corn-based diets, whereas WB inclusion decreased IDE in wheat-based diets, but STB supplementation increased IDE with or without WB. In corn-based diets, WB inclusion increased ND, whereas ND was decreased in wheat-based diets. Supplementation with STB had no effect on ND, but STB increased ND in wheat-based diets with and without WB. Ileal DE was greater (P < 0.05) for wheat- than corn-based diets on d 42. Wheat bran inclusion increased ND in corn-based diets whereas, with STB supplementation, there was no difference in ND with or without WB. There was no difference in ND with or without STB or WB in wheat-based diets. There was a significant STB × DT on the expression of GLUT-1 (P < 0.05). In corn-based diets, STB produced an upward expression of GLUT-1, whereas in wheat-based diets, STB supplementation had no effect. On d 42, stimbiotic supplementation produced upward (P < 0.05) expression of SGLT-1. In conclusion, STB supplementation in wheat- or corn-based diets and with WB inclusion improved energy digestibility. On the other hand, WB inclusion in wheat-based diets decreased nutrient digestibility especially on d 18, thus making room for a positive response to STB supplementation in wheat-based diets compared to the marginal response to STB supplementation observed in corn-based diets.

High Soluble Fiber Promotes Colorectal Tumorigenesis Through Modulating Gut Microbiota and Metabolites in Mice.

BACKGROUND & AIMS: Dietary fibers are mainly fermented by the gut microbiota, but their roles in colorectal cancer (CRC) are largely unclear. Here, we investigated the associations of different fibers with colorectal tumorigenesis in mice. METHODS: Apcmin/+ mice and C57BL/6 mice with azoxymethane (AOM) injection were used as CRC mouse models. Mice were fed with mixed high-fiber diet (20% soluble fiber and 20% insoluble fiber), high-inulin diet, high-guar gum diet, high-cellulose diet, or diets with different inulin dose. Germ-free mice were used for validation. Fecal microbiota and metabolites were profiled by shotgun metagenomic sequencing and liquid chromatography-mass spectrometry, respectively. RESULTS: Mixed high-fiber diet promoted colorectal tumorigenesis with increased tumor number and tumor load in AOM-treated and Apcmin/+ mice. Antibiotics use abolished the pro-tumorigenic effect of mixed high-fiber diet, while transplanting stools from mice fed with mixed high-fiber diet accelerated tumor growth in AOM-treated germ-free mice. We therefore characterized the contribution of soluble and insoluble fiber in CRC separately. Our results revealed that soluble fiber inulin or guar gum, but not insoluble fiber cellulose, promoted colorectal tumorigenesis in AOM-treated and Apcmin/+ mice. Soluble fiber induced gut dysbiosis with Bacteroides uniformis enrichment and Bifidobacterium pseudolongum depletion, accompanied by increased fecal butyrate and serum bile acids and decreased inosine. We also identified a positive correlation between inulin dosage and colorectal tumorigenesis. Moreover, transplanting stools from mice fed with high-inulin diet increased colonic cell proliferation and oncogene expressions in germ-free mice. CONCLUSION: High-dose soluble but not insoluble fiber potentiates colorectal tumorigenesis in a dose-dependent manner by dysregulating gut microbiota and metabolites in mice.

Comparative analysis of Chrysoporthe cubensis exoproteomes and their specificity for saccharification of sugarcane bagasse.

The phytopathogenic fungus Chrysoporthe cubensis is a relevant source of lignocellulolytic enzymes. This work aimed to compare the profile of lignocellulose-degrading proteins secreted by C. cubensis grown under semi-solid state fermentation using wheat bran (WB) and sugarcane bagasse (SB). The exoproteomes of the fungus grown in wheat bran (WBE) and sugarcane bagasse (SBE) were qualitative and quantitatively analyzed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Data are available via ProteomeXchange with identifier PXD046075. Label-free proteomic analysis of WBE and SBE showed that the fungus produced a spectrum of carbohydrate-active enzymes (CAZymes) with exclusive characteristics from each extract. While SBE resulted in an enzymatic profile directed towards the depolymerization of cellulose, the enzymes in WBE were more adaptable to the degradation of biomass rich in hemicellulose and other non-lignocellulosic polymers. Saccharification of alkaline pre-treated sugarcane bagasse with SBE promoted glucose release higher than commercial cocktails (8.11 g L-1), while WBE promoted the higher release of xylose (5.71 g L-1). Our results allowed an in-depth knowledge of the complex set of enzymes secreted by C. cubensis responsible for its high lignocellulolytic activity and still provided the identification of promising target proteins for biotechnological applications in the context of biorefinery.

Comparative study on chemical composition, functional properties of dietary fibers prepared from four China cereal brans.

Comparison of chemical composition and functional properties of insoluble and soluble dietary fiber (IDF, SDF) obtained from four China cereal brans was investigated. With findings, IDFs and SDFs for rice bran (RB), wheat bran (WB), highland barely bran (HBB) and tartary buckwheat bran (TBB) contained several monosaccharides such as arabinose, galactose, glucose, xylose, and galacturonic acid. The RBIDF was shrinking and formed a rugged microscopic structure, while the structure of WBIDF was dense and flat. HBBIDF and TBBIDF showed fold and flake structure. The glucose adsorption capacity of the HBBIDF was highest among all samples, which was 3.2 mmol/g. TBBIDF exhibited the highest value of cholesterol adsorption capacity (10.5 mg/g) at pH 7.0 and maximum binding capacity (BCmax, 365.2 µmol/g) for cadmium at pH 7.0 among all samples, respectively. As a result, HBBIDF and TBBIDF are potential fiber-rich ingredients in functional foods.

Structural property of extractable proteins and polysaccharides in wheat bran following a dual-enzymatic pretreatment and corresponding functionality.

The current study applied dual-enzymatic treatment via alcalase and Bacillus velezensis hydrolase for enhancing extraction of proteins and polysaccharides from wheat bran and modifying their corresponding structure. Results indicated the aqueous extract by enzymatic pretreatment (referred as EHWB) had an increased content of soluble substance, in which 18.5 % increased for carbohydrates and 11.4 % increased for proteins in the extract compared to the aqueous extract without enzymes (labeled as AEWB). Furthermore, compositions with lower molecular weight of 130 kDa and < 21.1 kDa for polysaccharides and proteins, respectively, were found in EHWB. Interestingly, EHWB had a twice higher radicals scavenging than that of AEWB, and digestive property indicated EHWB had a greater peptides production although glucose release was lower in gastric phase. Importantly, this is the first study to reveal that gut microbiota fermentation of EHWB resulted in faster generation of short-chain fatty acids at initial fermentation stage (6 h), followed a higher generation of butyrate at final fermentation stage (24 h). This fermentation property might be associated with its presence of lower molecular weight substrates and even the changes in the molecular structure induced by the enzymes. This study highlights a novel approach for developing a value-added product from wheat bran.

Fecal fermentation behavior and immunomodulatory activity of arabinoxylan from wheat bran.

Arabinoxylan (AX) is the predominant non-starch polysaccharide in wheat bran, known for its significant immunomodulatory activity. However, existing literature lacks comprehensive studies on AX fermentation by gut microbiota and its subsequent immunomodulatory mechanisms. In the present study, we aimed to investigate the effects of AX on the composition of gut microbiota and the characteristics of its immunomodulatory activity. For this purpose, an in vitro fermentation system and a cyclophosphamide-induced immunosuppressed mouse model were established to explore both the in vitro and in vivo effects of AX on gut microbiota and immune modulation. The results demonstrated that AX was metabolized by gut microbes and in turn to promoting the production of short-chain fatty acids (SCFAs), which concurrently led to a significant decrease in pH. Furthermore, AX treatment significantly changed the microbial composition, elevated the relative abundance of Actinobacteria while reducing that of Bacteroidetes. In the immunosuppressed mice, AX administration improved the thymus and spleen indices, mitigated spleen injury, and bolstered overall immunity. Moreover, AX altered the gut microbiota structure, increasing the abundance of Bacteroidetes and decreasing that of Firmicutes. These findings suggest that wheat bran-derived AX can modulate intestinal microbial composition, improve gut microecology, and enhance host immunity by targeting gut microbiota.