GH11 xylanase increases prebiotic oligosaccharides from wheat bran favouring butyrate-producing bacteria in vitro

In vitro evaluation of the application of an optimized xylanase cocktail for improved monogastric feed digestibility

Xylanases from glycoside hydrolase (GH) families 10 and 11 are common feed additives for broiler chicken diets due to their catalytic activity on the nonstarch polysaccharide xylan. This study investigated the potential of an optimized binary GH10 and GH11 xylanase cocktail to mitigate the antinutritional effects of xylan on the digestibility of locally sourced chicken feed. Immunofluorescence visualization of the activity of the xylanase cocktail on xylan in the yellow corn of the feed showed a substantial collapse in the morphology of cell walls. Secondly, the reduction in the viscosity of the digesta of the feed by the cocktail showed an effective degradation of the soluble fraction of xylan. Analysis of the xylan degradation products from broiler feeds by the xylanase cocktail showed that xylotriose and xylopentaose were the major xylooligosaccharides (XOS) produced. In vitro evaluation of the prebiotic potential of these XOS showed that they improved the growth of the beneficial bacteria Streptococcus thermophilus and Lactobacillus bulgaricus. The antibacterial activity of broths from XOS-supplemented probiotic cultures showed a suppressive effect on the growth of the extraintestinal infectious bacterium Klebsiella pneumoniae. Supplementing the xylanase cocktail in cereal animal feeds attenuated xylan's antinutritional effects by reducing digesta viscosity and releasing entrapped nutrients. Furthermore, the production of prebiotic XOS promoted the growth of beneficial bacteria while inhibiting the growth of pathogens. Based on these effects of the xylanase cocktail on the feed, improved growth performance and better feed conversion can potentially be achieved during poultry rearing.

Poultry gut health and beyond

Intestinal health is critically important for the digestion and absorption of nutrients and thus is a key factor in determining performance. Intestinal health issues are very common in high performing poultry lines due to the high feed intake, which puts pressure on the physiology of the digestive system. Excess nutrients which are not digested and absorbed in the small intestine may trigger dysbiosis, i.e. a shift in the microbiota composition in the intestinal tract. Dysbiosis as well as other stressors elicit an inflammatory response and loss of integrity of the tight junctions between the epithelial cells, leading to gut leakage. In this paper, key factors determining intestinal health and the most important nutritional tools which are available to support intestinal health are reviewed.

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2017-2018

This review is the tenth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization mass spectrometry (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2018. Also included are papers that describe methods appropriate to glycan and glycoprotein analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, new methods, matrices, derivatization, MALDI imaging, fragmentation and the use of arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides, and biopharmaceuticals. Most of the applications are presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions, and applications to chemical synthesis. The reported work shows increasing use of combined new techniques such as ion mobility and highlights the impact that MALDI imaging is having across a range of diciplines. MALDI is still an ideal technique for carbohydrate analysis and advancements in the technique and the range of applications continue steady progress.

Dietary fiber ameliorates lead-induced gut microbiota disturbance and alleviates neuroinflammation

Dietary fiber (DF) is a carbohydrate from the edible part of plants and has the functions of promoting gastrointestinal motility, regulating gut microbiota (GM) and improving health. Lead is a non-essential toxic heavy metal that can accumulate in the environment over time and enter the body through the respiratory tract, skin and gastrointestinal tract. Lead not only causes disturbances in GM but also leads to loss of homeostasis of immune functions, causes neuronal damage and results in neuroinflammation. The scientific literature has reported that DF had anti-inflammatory activity as a natural product. This review highlights the role of DF and its metabolic products in alleviating lead-induced neuroinflammation by inducing changes in the species and quantity of GM and regulating the immune system, providing a potential dietary protective strategy for lead-induced disease. © 2022 Society of Chemical Industry.

Direct Action of Non-Digestible Oligosaccharides against a Leaky Gut

The epithelial monolayer is the primary determinant of mucosal barrier function, and tight junction (TJ) complexes seal the paracellular space between the adjacent epithelial cells and represent the main "gate-keepers" of the paracellular route. Impaired TJ functionality results in increased permeation of the "pro-inflammatory" luminal contents to the circulation that induces local and systemic inflammatory and immune responses, ultimately triggering and/or perpetuating (chronic) systemic inflammatory disorders. Increased gut leakiness is associated with intestinal and systemic disease states such as inflammatory bowel disease and neurodegenerative diseases such as Parkinson's disease. Modulation of TJ dynamics is an appealing strategy aiming at inflammatory conditions associated with compromised intestinal epithelial function. Recently there has been a growing interest in nutraceuticals, particularly in non-digestible oligosaccharides (NDOs). NDOs confer innumerable health benefits via microbiome-shaping and gut microbiota-related immune responses, including enhancement of epithelial barrier integrity. Emerging evidence supports that NDOs also exert health-beneficial effects on microbiota independently via direct interactions with intestinal epithelial and immune cells. Among these valuable features, NDOs promote barrier function by directly regulating TJs via AMPK-, PKC-, MAPK-, and TLR-associated pathways. This review provides a comprehensive overview of the epithelial barrier-protective effects of different NDOs with a special focus on their microbiota-independent modulation of TJs.

Modified dietary fiber from cassava pulp affects the cecal microbial population, short-chain fatty acid, and ammonia production in broiler chickens

The objective of this study was to investigate the effects of modified dietary fiber from cassava pulp (M-DFCP) supplementation in broiler diets on cecal microbial populations, short-chain fatty acids (SCFAs), ammonia production, and immune responses. A total of 336, one-day-old male broiler chicks (Ross 308) were distributed over 4 dietary treatments in 7 replicate pens (n = 12 chicks) using a completely randomized design. Chicks were fed the control diet and 3 levels of M-DFCP (0.5, 1.0, and 1.5%) for an experimental duration of 42 d. The M-DFCP contained total dietary fiber (TDF), soluble dietary fiber (SDF), insoluble dietary fiber (IDF), cello-oligosaccharides (COS), and xylo-oligosaccharides (XOS) of approximately 280.70, 22.20, 258.50, 23.93, and 157.55 g/kg, respectively. The 1.0 and 1.5% M-DFCP supplementation diets showed positive effects on stimulating the growth of Lactobacillus spp. and Bifidobacterium spp., enhancing SCFAs (acetic, propionic, butyric acid, and branched SCFAs) and lactic acid concentrations during growing periods. Broilers fed 1.0 and 1.5% M-DFCP also exhibited a significant increase in caecal Lactobacillus spp. and lactic acid concentrations during the finisher period as well. In addition, M-DFCP also reduced cecal digesta and excreta ammonia production in broilers over both periods (0-21 and 22-42 d of age). However, M-DFCP did not exhibit any effect on total serum immunoglobulin (Ig) or lysozyme activity. In conclusion, this study shows that M-DFCP can be used as a dietary fiber source in broiler diets, with a recommended level of approximately 1.0%.

Lacticaseibacillus rhamnosus-Derived Exopolysaccharide Attenuates D-Galactose-Induced Oxidative Stress and Inflammatory Brain Injury and Modulates Gut Microbiota in a Mouse Model

This study aimed to investigate the protective effect of a novel exopolysaccharide EPSRam12, produced by Lacticaseibacillus rhamnosus Ram12, against D-galactose-induced brain injury and gut microbiota dysbiosis in mice. The findings demonstrate that EPSRam12 increases the level of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase, total antioxidant capacity, and the level of anti-inflammatory cytokine IL-10, while decreasing malonaldehyde, nitric oxide, pro-inflammatory cytokines including TNF-α, IL-1β, IL-6, MCP-1, and the mRNA expression of cyclooxygenase-2, inducible nitric oxide synthase, and the activation of nuclear factor-kappa-B in the brain tissues of D-galactose-treated mice. Further analyses reveal that EPSRam12 improves gut mucosal barrier function and increases the levels of short-chain fatty acids (SCFAs) in the intestine while restoring gut microbial diversity by enriching the abundance of SCFA-producing microbial genera Prevotella, Clostridium, Intestinimonas, and Acetatifactor while decreasing potential pathobionts including Helicobacter. These findings of antioxidative and anti-inflammatory effects in the brain and ameliorative effects on epithelial integrity, SCFAs and microbiota in the gut, provide novel insights into the effect of EPSRam12 intervention on the gut–microbiome–brain axis and should facilitate prospective understanding of microbial exopolysaccharide for improved host health.

Different enzymatic associations in diets of broiler chickens formulated with corn dried at various temperatures

The effect of supplementation of different enzymatic associations in the feed of broiler chickens formulated with corn dried at 80°C or 110°C on growth performance and carcass yield was evaluated. In addition, the influence of the different enzymatic associations on the cecal microbiota was studied. One-day-old male broiler chicks (1,320) were distributed in a completely randomized design in a 2 × 5 factorial arrangement (6 replicates; 22 birds/replicate). The treatments were 2 corn drying temperatures (80°C and 110°C) and 5 diets. The diets consisted of a positive control (PC), a negative control (NC) with a reduction of 100 kcal/kg of apparent metabolizable energy, and 3 enzyme combinations added to the NC diet: amylase, amylase + xylanase, and amylase + xylanase + protease. The feed conversion ratio (FCR) from 1 to 7 d of chickens fed diets formulated with corn dried at 80°C was better (P = 0.045) than that of chickens fed diets dried at 110°C. Regardless of the enzymatic association, the supplementation improved body weight gain (P = 0.01) of the NC group to the same level as the PC group. The FCR of the NC was similar to that of the PC only when the 3 enzymes were included from 1 to 21 d (P = 0.001) and regardless of the enzymatic association for the period from 1 to 42 d (P = 0.007). Regarding cecal microbiota, the alpha diversity was similar among the groups (P > 0.05). The beta-diversity analysis showed that the microbiota of the birds receiving the combination of the 3 enzymes was similar to that of birds fed the PC diet (P = 0.18; R = 0.074), with a similar effect observed for the predicted metabolic functions (Linear discriminant analysis effect size). In conclusion, chickens fed diets formulated with corn dried at 80°C had better FCR during the prestarter phase. The enzymatic supplementation improved the FCR of the birds, which may partially be explained by the modulation of the cecal microbiota.

Novel approach to produce biomass-derived oligosaccharides simultaneously by recombinant endoglucanase from Trichoderma reesei

The recombinant endoglucanase gene (EG I) from Trichoderma reesei was successfully expressed in Pichia pastoris for the purpose of producing oligosaccharides from various biomass-derived substrates. Interestingly, the recombinant endoglucanase I (ReEG I) showed the catalytic activity towards both cellulose and xylan hydrolysis, yet it was more efficient with xylans. Among various glucans and xylans substrates (paper pulp, carboxymethylated cellulose, oat spelt xylan, birchwood xylan), birchwood xylan displayed a higher yield of xylooligosaccharides (XOS) (69.5 % after optimization). Eventually, it was observed that ReEG I could simultaneously produce XOS and COS, when the alkali-extracted corncob residues were used as substrate. This is the first report on simultaneous production of XOS and COS by recombinant endoglucanase I from Trichoderma reesei expressed in Pichia pastoris, where a novel application of genetically engineered enzymes is proposed to provide an attractive application for high value utilization of biomass.

Review: innovation through research in the North American pork industry

This article involved a broad search of applied sciences for milestone technologies we deem to be the most significant innovations applied by the North American pork industry, during the past 10 to 12 years. Several innovations shifted the trajectory of improvement or resolved significant production limitations. Each is being integrated into practice, with the exception being gene editing technology, which is undergoing the federal approval process. Advances in molecular genomics have been applied to gene editing for control of porcine reproductive and respiratory syndrome and to identify piglet genome contributions from each parent. Post-cervical artificial insemination technology is not novel, but this technology is now used extensively to accelerate the rate of genetic progress. A milestone was achieved with the discovery that dietary essential fatty acids, during lactation, were limiting reproduction. Their provision resulted in a dose-related response for pregnancy, pregnancy maintenance and litter size, especially in maturing sows and ultimately resolved seasonal infertility. The benefit of segregated early weaning (12 to 14 days of age) was realized for specific pathogen removal for genetic nucleus and multiplication. Application was premature for commercial practice, as piglet mortality and morbidity increased. Early weaning impairs intestinal barrier and mucosal innate immune development, which coincides with diminished resilience to pathogens and viability later in life. Two important milestones were achieved to improve precision nutrition for growing pigs. The first involved the updated publication of the National Research Council nutrient requirements for pigs, a collaboration between scientists from America and Canada. Precision nutrition advanced further when ingredient description, for metabolically available amino acids and net energy (by source plant), became a private sector nutrition product. The past decade also led to fortuitous discoveries of health-improving components in ingredients (xylanase, soybeans). Finally, two technologies converged to facilitate timely detection of multiple pathogens in a population: oral fluids sampling and polymerase chain reaction (PCR) for pathogen analysis. Most critical diseases in North America are now routinely monitored by oral fluid sampling and prepared for analysis using PCR methods.

Production, characteristics, and biotechnological applications of microbial xylanases

Microbial xylanases have gathered great attention due to their biotechnological potential at industrial scale for many processes. A variety of lignocellulosic materials, such as sugarcane bagasse, rice straw, rice bran, wheat straw, wheat bran, corn cob, and ragi bran, are used for xylanase production which also solved the great issue of solid waste management. Both solid-state and submerged fermentation have been used for xylanase production controlled by various physical and nutritional parameters. Majority of xylanases have optimum pH in the range of 4.0-9.0 with optimum temperature at 30-60 °C. For biochemical, molecular studies and also for successful application in industries, purification and characterization of xylanase have been carried out using various appropriate techniques. Cloning and genetic engineering are used for commercial-level production of xylanase, to meet specific economic viability and industrial needs. Microbial xylanases are used in various biotechnological applications like biofuel production, pulp and paper industry, baking and brewing industry, food and feed industry, and deinking of waste paper. This review describes production, characteristics, and biotechnological applications of microbial xylanases.

Enzymes and/or combination of organic acid and essential oils supplementation in pasture-fed free-range laying hens increased the digestibility of nutrients and non-starch polysaccharides

Pasture intake can be a major challenge for free-ranging hens. This study was conducted to examine pasture digestion and to manage its negative effects. A total of 300 ISA Brown laying hens were used to investigate the effect of time on range (T) in short-term (6 wk) and long-term (12 wk) of 2 range types (R) (gravel vs. pasture) and dietary supplements (F) (T1 = xylanase; T2 = xylanase/beta-glucanase/pectinase/protease; T3 = xylanase/benzoic acid/essential oils) on crude protein, crude fiber, acid detergent fiber, neutral detergent fiber, non-starch polysaccharides (NSP), calcium and phosphorus digestibility, pH of the crop, and ileum digesta viscosity and morphology. Hens exposed to the range for 12 wk had lower (P < 0.05) digestibility of crude protein, insoluble rhamnose, ribose, and lower ileal pH compared to hens that ranged for 6 wk. Hens ranging on pasture had lower digestibility (P < 0.05) of crude protein, acid detergent fiber, neutral detergent fiber, insoluble arabinose, and insoluble xylose, but higher digestibility (P < 0.05) of insoluble mannose and glucose compared to hens that ranged on gravel. Hens fed T2 and T3 had higher digestibility (P < 0.05) of CP, acid detergent fiber, and neutral detergent fiber compared to hens fed T1. Hens fed T2 had higher digestibility (P < 0.05) of free oligosaccharide arabinose and xylose than those fed T1 or T3 diets. A significant interaction between T × R was detected for crude fiber digestibility and villus height. Digestibility of crude fiber was reduced and villus height was increased in hens ranged on pasture for 12 wk compared to 6 wk. An interaction between R × F was observed on phosphorus and soluble NSP digestibility (P < 0.05). Hens fed T2 and T3 diets had lower digestibility of phosphorus and NSP on gravel than on pasture. In conclusion, pasture consumption impaired the digestibility of nutrients. Supplementing free-range diets with a multi-enzyme or xylanase/benzoic acid/essential oil product reduced these negative effects and increased the ileal nutrient digestibility.

A novel glucuronoxylan hydrolase produced by fermentation is safe as feed additive: toxicology and tolerance in broiler chickens

The current study presents a safety evaluation of a novel glucuronoxylan hydrolase (EC 3.2.1.136) from Bacillus subtilis produced in Bacillus licheniformis. The glucuronoxylan hydrolase preparation did not exhibit irritative potential to the eye and skin when applied in in vitro models. The glucuronoxylan hydrolase preparation was non-mutagenic and non-clastogenic in in vitro tests. Oral administration of the glucuronoxylan hydrolase preparation to rats did not cause any adverse effect in a 90-days subchronic toxicity study. A tolerance study was performed with broiler chickens and confirmed that this glucuronoxylan hydrolase is safe for broiler chickens when fed at the maximum recommended dose, as well as at the 10 times higher dose. In conclusion, there are no safety concerns with using this novel glucuronoxylan hydrolase as a feed additive as it is toxicologically inert and the glucuronoxylan hydrolase is well tolerated by broiler chickens. The beneficial safety evaluation of glucuronoxylan hydrolase is consistent with the fact that this type of enzyme is ubiquitous in nature.

Beneficial Effect of Intestinal Fermentation of Natural Polysaccharides

With the rapid development of modern society, many chronic diseases are increasing including diabetes, obesity, cardiovascular diseases, etc., which further cause an increased death rate worldwide. A high caloric diet with reduced natural polysaccharides, typically indigestible polysaccharides, is considered a health risk factor. With solid evidence accumulating that indigestible polysaccharides can effectively prevent and/or ameliorate symptoms of many chronic diseases, we give a narrative review of many natural polysaccharides extracted from various food resources which mainly contribute their health beneficial functions via intestinal fermentation.

The evolution and application of enzymes in the animal feed industry: the role of data interpretation

1. Enzymes have been used commercially for nearly 40 years and save significant costs through sparing of expensive nutrients but the mechanism by which this is achieved is still debated. 2. The research focused on non-starch polysaccharidase (NSPase) enzymes is used as an example of where greater progress could have been made if the details of the work had been described more fully and the analysis of the data generated had been broader in scope and more critical. 3. Lack of standardisation of the details presented in the materials and methods has been identified as a significant barrier to meaningful retrospective analysis and thus limits advances in the understanding of the mode of action of these enzymes. 4. The identity of the enzyme employed and its activity is often lacking, and more importantly the purity is rarely disclosed. Contaminant activities which are neither listed nor assayed could play a significant role in the responses observed. 5. The dose optimum of most enzymes is often considerably higher than that employed in most studies. Thus studies claiming synergy between two 'activities' should ensure that the response is not related to each enzyme simply augmenting the dose of just one activity in the finished feed. This is a common problem, and coupled with the lack of factorial experiments to justify the presence of each enzyme in a multi-enzyme product, it is not surprising that there is still debate as to whether single or multi-enzymes are best suited poultry rations. 6. The three proposed mechanisms for NSPases (viscosity, cell wall and prebiotic) are discussed, and along with their strengths and weaknesses it is suggested that a re-evaluation of each is needed. Viscosity may have to be re-evaluated as being a function not only of the cereal being fed, but of the age of the animal as well. The cell wall theory as described is poorly modelled in vitro and hence the validity of these data is questioned. The prebiotic theory may need significant modification as it appears that the quantities of oligomers produced are insufficient to generate the additional volatile fatty acids (VFA)'s reported. It is likely that all three mechanisms play a role in the responses observed, but the prebiotic mechanism probably plays by far the most important part in low viscosity diets. 7. Future research would be improved if it considered all potential mechanisms when designing a trial. Significant failings are apparent as a result of adherence to tenets in explanation of the results. Most importantly, it should be emphasised that a hypothesis is there to be tested, not defended.

Growth Capacity of a Novel Potential Probiotic Lactobacillus paracasei K5 Strain Incorporated in Industrial White Brined Cheese as an Adjunct Culture

In this study, a novel potential probiotic strain Lactobacillus paracasei K5, previously isolated from traditional Greek Feta cheese and kefir grains, was evaluated as an adjunct culture for industrial white brined cheese production. Targeting industrial applications, apart from free cell cultures, a novel ready-to-use freeze-dried immobilized biocatalyst was prepared. The biocatalyst composed of L. paracasei K5 cells immobilized on delignified wheat bran prebiotic carrier and was freeze-dried without cryoprotectants. The adjunct free or immobilized culture was added separately without prior adaptation during white brined cheese manufacture and the produced cheeses were compared with commercial white brined cheeses. Several parameters that affect the acceptability and quality of the cheeses, including microbial populations, physicochemical parameters, volatile by-products and organoleptic characteristics, were analyzed through 70 days of storage. Results showed that the viability of the adjunct culture added either free or immobilized remained in high levels (7 to 8 log cfu/g) during maturation and storage. In addition, all white brined cheeses with the adjunct probiotic culture showed a sharp decrease in spoilage and pathogenic microorganisms such as enterobacteria, salmonella, staphylococci and coliforms during cheese maturation, especially when compared with the commercial white brined cheeses. Finally, after maturation time exceeded, all cheeses were characterized as safe for human consumption. Cheeses volatile compounds were significantly enhanced by the incorporated immobilized biocatalysts. These findings indicate the potential industrial use of freeze-dried ready-to-use immobilized lactobacilli as reinforcement adjunct cultures for the production of good-quality functional cheese products.

PRACTICAL APPLICATION

The launch on market of novel foods developed by the incorporation of functional ingredients provides potential benefits to consumers' diet and new business opportunities for producers. Probiotic food products are one significant category of functional foods. Thus, this study focused on the development of a novel ready-to-use freeze-dried potential probiotic biocatalyst for functional white brined cheese production. The potential industrial application of such biocatalysts is highlighted by their incorporation as adjunct cultures that resulted in good-quality functional cheeses.