Piglets performance, nutrient digestibility and gut health in response to feeding Ulva lactuca seaweed supplemented with a recombinant ulvan lyase or a commercial carbohydrase mixture.

Ulva lactuca, a green seaweed, may be an alternative source of nutrients and bioactive compounds for weaned piglets. However, it has a recalcitrant cell wall rich in a sulphated polysaccharide - ulvan - that is indigestible to monogastrics. The objective of this study was to evaluate the effect of dietary incorporation of 7% U. lactuca, combined with carbohydrases supplementation (commercial carbohydrase mixture or recombinant ulvan lyase), on growth performance, nutrient digestibility and gut health parameters (morphology and microbiota) of weaned piglets. The experiment was conducted over 14 days using 40 weaned piglets randomly allocated to one of four experimental diets: a control diet based on wheat-maize-soybean meal, a diet with 7% U. lactuca replacing the control diet (UL), a diet with UL supplemented with 0.005% Rovabio® Excel AP, and a diet with UL supplemented with 0.01% of a recombinant ulvan lyase. The dietary treatments had no major effects on growth performance, nitrogen balance and gut content variables, as well as histological measurements. Contrarily, dry matter and organic matter digestibility decreased with dietary seaweed inclusion, while hemicellulose digestibility increased, suggesting a high fermentability of this cell wall fraction independently of carbohydrases supplementation. Some beneficial microbial populations increased as a consequence of enzymatic supplementation (e.g., Prevotella), while seaweed diets as a whole led to an increased abundance of Shuttleworthia, Anaeroplasma and Lachnospiraceae_NK3A20_group, all related with a healthier gut. It also decreased Lactobacillus when compared to controls, which is possibly related to increased bioavailability of seaweed zinc. This study indicates that, under these experimental conditions, up to 7% dietary U. lactuca has no detrimental effect on piglet growth, despite decreasing acid detergent fibre digestibility. Carbohydrases supplementation of Ulva diets is not required at this incorporation level.

Quantification of hydrolysis activity in a biological wastewater treatment context.

This paper reviews currently available methods for hydrolysis activity monitoring of the most commonly encountered enzyme categories in biological wastewater treatment. While highlighting the relevant methods for protein, lipid, carbohydrate, organic phosphate, and ester hydrolysis, the discussion of their pros and cons is predominantly aimed at revealing the relevance of the to-be-hydrolyzed substrates that are used in the methods. These "substrates" should mimic the proteins, lipids, or other polymers that are present in the wastewater and are in the reviewed methods (i) real substrates (i.e., naturally present in the wastewater), (ii) chromogenic substrates, or (iii) fluorogenic substrates. We conclude that exploiting relevant substrates such as casein or starch, containing fluorophores, has the highest potential for meaningful high throughput hydrolysis quantification and that lipase activity monitoring is still cumbersome. Monitoring the hydrolysis activity in biological wastewater treatment systems is an underdeveloped area. With this review, which aims at providing a condensed and practice-oriented overview, we hope to facilitate the start or continuation of such monitoring. This monitoring will only grow in importance, given the transition from wastewater treatment plants towards water resource recovery facilities. KEY POINTS: • Colorimetric-based methods are vulnerable to sludge matrix interference. • Bonds in p-nitrophenol-based methods are not representative for the targeted substrates. • Direct methods with relevant/real substrates are preferred. • Fluorophore-containing (real) substrates enable high throughput screening.

Effects of dietary xylanase plus ß-glucanase levels on total-tract nutrient and energy digestibility and N balance of growing pigs fed diets containing corn distillers dried grains.

The addition of corn distillers dried grains (corn-DDG) to pig diets has been limited due to concerns about fiber content. The aim of the present study was to determine the metabolizable energy of corn-DDG (Exp. I) and the dose-response effects of dietary xylanase plus ß-glucanase on the nutrient and energy digestibility of growing pigs fed diets containing 25% corn-DDG (Exp. II). Pigs in individual cages were subjected to feeding periods of 5 days for voluntary feed intake quantification followed by 5 days for collection of feces and urine. In Exp. I, 10 castrated male pigs with 61.10 ± 3.25 kg BW distributed in a randomized complete block design experiment with five replications were fed a reference diet or a test diet (75% reference diet plus 25% corn-DDG). In Exp. II, 10 castrated male pigs with 29.69 ± 3.57 kg BW distributed in a Latin square design (two squares with four replicates in time) experiment were fed with 5 dietary xylanase plus ß-glucanase levels (0, 50, 100, 200, or 400 mg/kg) added to diets formulated with 25% corn-DDG. The corn-DDG had 26.5% crude protein, 5.94% ether extract, 55.5% neutral detergent fiber (NDF), and 4.248 kcal/kg gross energy. The metabolizable energy of corn-DDG was 3.657 ± 189 kcal/kg. Increasing dietary xylanase plus ß-glucanase quadratically influenced (P < 0.05) the NDF digestibility and digestible energy in growing pigs fed diets containing 25% corn-DDGS. Compared to the control, dietary xylanase plus ß-glucanase addition increased digestibility and reduced metabolizability of crude protein. The addition of dietary xylanase plus ß-glucanase to growing pig diets containing corn-DDG increased NDF digestibility, allowing for additional dietary energy and protein availability.

Microbially-derived cocktail of carbohydrases as an anti-biofouling agents: a 'green approach'.

Enzymes, also known as biocatalysts, display vital properties like high substrate specificity, an eco-friendly nature, low energy inputs, and cost-effectiveness. Among their numerous known applications, enzymes that can target biofilms or their components are increasingly being investigated for their anti-biofouling action, particularly in healthcare, food manufacturing units and environmental applications. Enzymes can target biofilms at different levels like during the attachment of microorganisms, formation of exopolymeric substances (EPS), and their disruption thereafter. In this regard, a consortium of carbohydrases that can target heterogeneous polysaccharides present in the EPS matrix may provide an effective alternative to conventional chemical anti-biofouling methods. Further, for complete annihilation of biofilms, enzymes can be used alone or in conjunction with other antimicrobial agents. Enzymes hold the promise to replace the conventional methods with greener, more economical, and more efficient alternatives. The present article explores the potential and future perspectives of using carbohydrases as effective anti-biofilm agents.

Plasma Metabolites and Liver Composition of Broilers in Response to Dietary Ulva lactuca with Ulvan Lyase or a Commercial Enzyme Mixture.

The effect of a high incorporation level of Ulva lactuca, individually and supplemented with a Carbohydrate-Active enZyme (CAZyme) on broilers' plasma parameters and liver composition is assessed here. Twenty one-day-old Ross 308 male broilers were randomly assigned to one of four treatments (n = 10): corn/soybean meal based-diet (Control); based-diet with 15% U. lactuca (UL); UL diet with 0.005% of commercial carbohydrase mixture; and UL diet with 0.01% of recombinant ulvan lyase. Supplementing U. lactuca with the recombinant CAZyme slightly compromised broilers' growth by negatively affecting final body weight and average daily gain. The combination of U. lactuca with ulvan lyase also increased systemic lipemia through an increase in total lipids, triacylglycerols and VLDL-cholesterol (p < 0.001). Moreover, U. lactuca, regardless of the CAZyme supplementation, enhanced hepatic n-3 PUFA (mostly 20:5n-3) with positive decrease in n-6/n-3 ratio. However, broilers fed with U. lactuca with ulvan lyase reduced hepatic α- and γ-tocopherol concentrations relative to the control. Conversely, the high amount of pigments in macroalga diets led to an increase in hepatic ß-carotene, chlorophylls and total carotenoids. Furthermore, U. lactuca, alone or combined with CAZymes, enhanced hepatic total microminerals, including iron and manganese. Overall, plasma metabolites and liver composition changed favorably in broilers that were fed 15% of U. lactuca, regardless of enzyme supplementation.

Supplemental impact of cassava (Manihot esculenta Crantz) hard pellet and residue pellet-based diet as a replacement for corn on the growth performance, total tract digestibility and blood profiles in pigs.

The present study was conducted to evaluate the effect of cassava hard pellet and residue pellet-based diet as a replacement for corn on the growth performance, total tract digestibility and blood profile in pigs. Three experiments were conducted to evaluate the processed cassava as replacement for corn in pigs. In Exp. 1, seventy-two weanling pigs with an average initial body weight of 6.44 ± 0.52 kg were assigned to one of the two treatments: CON, basal diet, and CHP, basal diet with cassava hard pellet for 28 days trial. The dietary inclusion of CHP had significantly decreased average daily gain of weanling pigs during d 1-14 and the overall experimental period. In addition, significant reduction was observed on gain-to-feed ratio during d 1-14, while no effect was noted on average daily feed intake. Exp. 2 was carried out for 42 days, in which 84 growing pigs were randomly assigned to 1 of 3 treatments with 4 pigs/pen and 7 pen/treatment. The three dietary treatments were supplement with 0%, 20% and 40% of cassava. Dietary inclusion of cassava supplementation has failed to affect the growth performance and blood profile during overall experiment. In Exp. 3, a total of 96 crossbred finishing pigs were randomly assigned to one of four dietary treatments containing 25% cassava in a 2 × 2 factorial design with two different levels of energy with or without 0.1% carbohydrase for 28 days. Pigs fed 0.1% carbohydrase with high energy diet reduced average daily feed intake and increased gain-to-feed ratio compared to those fed low energy diet. However, significantly enhanced nutrient digestibility in both energy and carbohydrase groups were observed. In summary, the inclusion of cassava basal diet with 0.1% carbohydrase supplementation has beneficially enhanced the growth performance and nutrient digestibility of pigs.

The effect of graded inclusions of waxy starch hull-less barley and a multi-component exogenous carbohydrase on the growth performance, nutrient digestibility and intestinal morphometry of broiler chickens.

1. A 21-d experiment was conducted to investigate the effect of graded inclusions of waxy starch hull-less (WSHL) barley and a multi-component exogenous carbohydrase on the growth performance, nutrient digestibility and intestinal morphometry of broiler chickens. Five levels of WSHL barley inclusion (0, 65, 130, 195 and 260 g/kg) in a wheat-based diet, and two levels of enzyme supplementation (0 and 150 g/tonne of feed) were evaluated in a 5 × 2 factorial arrangement of 10 dietary treatments. All diets were equivalent in metabolisable energy and digestible amino acid content. A total of 400, one-d-old male broilers (five cages/treatment; eight birds/cage) were used in the experiment. 2. Regardless of enzyme supplementation, feed intake declined (P < 0.001) with increasing inclusion of WSHL barley. Increasing levels of WSHL barley (P < 0.001) and supplemental enzyme (P < 0.01) increased gain to feed ratio. 3. Birds fed diets with 0 g/kg WSHL barley showed the lowest (P < 0.001 to 0.01) digestibility for all nutrients except starch. Only starch digestibility was improved (P < 0.05) by enzyme supplementation. The nitrogen-corrected apparent metabolisable energy improved with increasing inclusion of WSHL barley (P < 0.001) and supplemental enzyme (P < 0.001). Increasing inclusion of WSHL barley increased the relative weight of gizzard (P < 0.001) and reduced jejunal digesta viscosity (P < 0.01). Supplemental enzyme (P < 0.001) reduced digesta viscosity. 4. All levels of WSHL barley inclusion improved digestibility of dry matter, nitrogen and fat, whilst energy utilisation improved at inclusions of 130 g/kg WSHL and above, probably due to lowered digesta viscosity and better development of the gizzard. Gain to feed ratio, starch digestibility, energy utilisation and jejunal digesta viscosity can benefit from carbohydrase supplementation in wheat-based diets, regardless of barley inclusion level.

Influence of inclusion level of barley in wheat-based diets and supplementation of carbohydrase on growth performance, nutrient utilisation and gut morphometry in broiler starters.

1. The influence of barley inclusion level and supplementation of a multi-component non-starch polysaccharide degrading enzyme on performance and nutrient utilisation in broilers was investigated. Normal-starch hulled barley was evaluated with five levels of inclusion (0, 141, 283, 424 and 565 g/kg) in a wheat-based diet and two levels of enzyme supplementation (0 and 150 g/tonne of feed; a 5 × 2 factorial arrangement of 10 dietary treatments). All diets were equivalent in metabolisable energy and digestible amino acid contents. A total of 400, one-d old male broilers (five cages/treatment; eight birds/cage) were used in the experiment.2. Regardless of enzyme supplementation, weight gain (WG) increased up to 283 g/kg of barley and was reduced afterwards (P < 0.01). Increasing levels of barley resulted in greater (P < 0.001) gain per feed (G/F). Enzyme addition increased WG (P < 0.05) and G/F (P < 0.001) at each barley inclusion level.3. Birds fed diets with 0 and 565 g/kg barley showed the lowest and highest (P < 0.001to 0.05) digestibility for all nutrients measured, respectively. Digestibility of all nutrients was improved by enzyme supplementation at each barley inclusion level (P < 0.05). The nitrogen-corrected apparent metabolisable energy improved with increasing inclusion of barley (P < 0.001) and supplemental enzyme (P < 0.01). Increasing inclusion of barley increased the relative weight of gizzard (P < 0.001) and reduced jejunal digesta viscosity (P < 0.001). Supplemental enzyme (P < 0.001) reduced digesta viscosity.4. The optimum inclusion level of barley, with respect to growth performance, was 283 g/kg of diet. Increasing barley inclusion improved nutrient and energy utilisation, possibly through lowered digesta viscosity and better function of the gizzard. Feed efficiency and nutrient and energy utilisation can benefit from carbohydrase supplementation in barley-based diets, regardless of barley inclusion level.

Nutritional evaluation of two barley cultivars, without and with carbohydrase supplementation, for broilers: metabolisable energy and standardised amino acid digestibility.

1. Two experiments were conducted to assess the nitrogen-corrected apparent metabolisable energy (AMEn; Exp. 1; 288 Ross 308 male broilers at d 14; 36 cages with eight birds each) and coefficient of standardised ileal digestibility (CSID) of amino acids (AA; Exp. 2; 336 Ross 308 male broilers at d 21; 42 cages with eight birds each) of two barley cultivars for broilers in comparison to wheat, without or with a multi-component non-starch polysaccharide (NSP) degrading enzyme. A 3 × 2 factorial arrangement of treatments was used in both experiments with three types of grains (normal starch hulled barley [NSH], waxy starch hull-less barley [WSHL], and wheat) and two levels of enzyme supplementation (0 and 200 g/tonne of feed). Enzyme supplemented diets contained 406 and 128 of endo-1, 4-ß-xylanase and endo-1, 3 (4)-ß-glucanase units per kg of feed, respectively. 2. Analysis showed that the starch content was higher in NSH (610 g/kg) than in wheat (537 g/kg) and WSHL (554 g/kg), and the composition of starch differed markedly among the grain types. The ß-glucan content was considerably higher in WSHL (68.6 g/kg) compared to NSH (38.5 g/kg) and wheat (7.74 g/kg). The contribution of soluble fraction to the total non-starch polysaccharides was higher in WSHL (38.2%) compared to NSH and wheat (17.1% and 13.3%, respectively). 3. A significant (P < 0.01) interaction was observed between the grain type and enzyme supplementation for AMEn. The WSHL, with the highest content of ß-glucan, showed the greatest response to enzyme supplementation for AMEn. 4. Birds fed wheat- and WSHL-based diets had the highest and lowest CSID of nitrogen and most of AA, respectively, with NSH diets being intermediate. Regardless of grain type, enzyme supplementation increased (P < 0.05) the CSID of nitrogen. 5. These data suggest that ß-glucan content plays an important role in determining the digestibility of nutrients in barley for broilers, resulting in a better feeding value for NSH over WSHL. Supplementation of a multi-component NSP-degrading enzyme can improve the feeding value of barley in broiler diets by increasing the digestibility with the effect being more pronounced in WSHL barley.

First characterization of fucosidases in spiders.

l-fucose is a constituent of glycoconjugates in different organisms. Fucosidases catalyze the removal of fucose residues, and have been correlated to different physiological and pathological processes, such as fertilization, cancer, fucosidosis, and digestion in molluscs and ticks. An α-l-fucosidase sequence was identified from the transcriptome and proteome from the midgut diverticula of the synanthropic spider Nephilingis cruentata. In this article, we describe the isolation of this α-l-fucosidase and the characterization of its activity using substrates and inhibitors demonstrating different specificities among fucosidases. The enzyme had a Km of 32 and 400 µM for 4-methylumbelliferyl α-l-fucopyranoside and 4-nitrophenyl α-l-fucopyranoside, respectively; and was unable to hydrolyze fucoidan. Nephilingis cruentata α-l-fucosidase was inhibited competitively by fucose and fuconojyrimycin. The fucosidase had two distinct pH optima even in the isolated form, due to oligomerization dependent on pH, as previously described to other fucosidases. Alignment and molecular homology modeling of the protein sequence with other fucosidases indicated that the active sites and catalytic residues were different, including residues involved in acid/base catalysis. Phylogenetic analysis showed, for the first time, gene-duplication events for fucosidases in Arachnida species. All these data reveal that studies on fucosidases in organisms distinct from bacteria, fungi, and humans are important.

The unresolved role of dietary fibers on mineral absorption.

Dietary fiber is a complex nutritional concept whose definition and method of analysis has evolved over time. However, literature on the role of dietary fiber on mineral bioavailability has not followed pace. Although in vitro studies revealed mineral binding properties, both animal and human studies failed to show negative effects on mineral absorption, and even in some cases reported absorption enhancing properties. The existing literature suggests that dietary fibers have negative effects on mineral absorption in the gastrointestinal tract largely due to mineral binding or physical entrapment. However, colonic fermentation of dietary fibers may offset this negative effect by liberating bound minerals and promoting colonic absorption. However, existing studies are limited since they did not control for more potent mineral absorption inhibitors such as phytates and polyphenols. Animal studies have mostly been on rats and hence difficult to extrapolate to humans. Human studies have been mostly on healthy young men, who likely to have an adequate store of iron. The use of different types and amounts of fibers (isolated/added) with varying physiological and physicochemical properties makes it difficult to compare results. Future studies can make use of the opportunities offered by enzyme technologies to decipher the role of dietary fibers in mineral bioavailability.

Enzyme Activity, Cold Hardiness, and Supercooling Point in Developmental Stages of Acrosternum arabicum (Hemiptera: Pentatomidae).

Several species of pentatomid bugs feed on pistachio fruits in Iran. Acrosternum arabicum Wagner (Hemiptera: Pentatomidae) is one of the most important pests of pistachio in Rafsanjan, Iran. This study was carried out to investigate the carbohydrase activities, supercooling points, and cold hardiness profiles of different developmental stages of A. arabicum under laboratory conditions. The midgut amylolytic of A. arabicum showed an optimal pH at 7.0. The highest amylolytic activity was found in the female adults (35.41 ± 0.90 nmol/min/gut). The mean amylolytic activity measured in first instar nymph was 6.75 ± 0.54 nmol/min/gut. Midgut α- and ß-glucosidase showed an optimal activity at pH 5 and 7, respectively. These activities increased from first (83 ± 5 and 54 ± 5 nmol/min, respectively) to fifth (881 ± 17 and 237 ± 14 nmol/min, respectively) instar nymphs. The enzyme activities increased in the adults. Midgut α- and ß-galactosidase showed an optimal activity at pH 5. α- and ß-galactosidase activities were low in the first instar nymphs (73 ± 5 and 21 ± 3 nmol/min, respectively). The level of α- and ß-galactosidase activities in the female adults (533 ± 18 and 246 ± 6 nmol/min, respectively) was higher than the nymphs. The lowest super cooling points (-19 and -18.2 °C, respectively) and the highest cold hardiness (22 and 18% following 24 h exposure at - 20 °C, respectively) were recorded for the eggs and adult females.

Effects of exogenous proteases without or with carbohydrases on nutrient digestibility and disappearance of non-starch polysaccharides in broiler chickens.

The objective of the current study was to evaluate the effect of a subtilisin protease, without or with inclusion of carbohydrases, on digestibility and retention of energy and protein, as well as the solubilization and disappearance of non-starch polysaccharides (NSP) from corn-soybean meal based diets fed to broiler chickens. Two hundred eighty-eight Ross 308 male broiler chickens were used for the experiment. On d 14, the birds were weighed and allocated to 6 treatments and 8 replicates per treatment with 6 birds per replicate. Treatments were: 1) corn-soybean meal based control diet; 2) control diet plus supplemental protease at 5,000 (P5000) protease units (PU)/kg); 3) control plus 10,000 PU/kg protease (P10000); or control plus an enzyme combination containing xylanase, amylase, and protease (XAP) added to achieve protease activity of: 4) 2,500 PU/kg (XAP2500); 5) 5,000 PU/kg (XAP5000); or 6) 10,000 PU/kg (XAP10000). The enzymes in XAP were combined at fixed ratios of 10:1:25 of xylanase:amylase:protease. Data were analyzed by ANOVA and specific orthogonal contrasts between treatments were performed. Addition of xylanase and amylase increased (P < 0.05) the ileal digestibility of protein by 4.2% and 2.1% at XAP5000 and XAP10000, respectively (relative to P5000 and P10000, respectively), exhibiting a plateau after the XAP5000 dose. Increment (P < 0.05) in AME due to protease was evident, particularly in P10000. At the ileal level, XAP reduced (P < 0.05) the flow of insoluble xylose and arabinose, which indicates an increase in the solubilization of arabinoxylan polymers in the small intestine. Protease on its own reduced (P < 0.05) the flow of insoluble arabinose but did not affect the flow of insoluble xylose. XAP reduced (P < 0.05) the pre-cecal flow of insoluble and total glucose and galactose. It was concluded that whereas protease by itself improved nutrient utilization and increased solubilization of NSP components, at the lower dose, a combination of xylanase, amylase, and protease produced effects greater than those of protease alone.

Carbohydrases in the digestive system of the spined soldier bug, Podisus maculiventris (Say) (Hemiptera: Pentatomidae).

The spined soldier bug, Podisus maculiventris, is a generalist predator of insects and has been used in biological control. However, information on the digestion of food in this insect is lacking. Therefore, we have studied the digestive system in P. maculiventris, and further characterized carbohydrases in the digestive tract. The midgut of all developmental stages was composed of anterior, median, and posterior regions. The volumes of the anterior midgut decreased and the median midgut increased in older instars and adults, suggesting a more important role of the median midgut in food digestion. However, carbohydrase activities were predominant in the anterior midgut. In comparing the specific activity of carbohydrases, α-amylase activity was more in the salivary glands (with two distinct activity bands in zymograms), and glucosidase and galactosidase activities were more in the midgut. Salivary α-amylases were detected in the prey hemolymph, demonstrating the role of these enzymes in extra-oral digestion. However, the catalytic efficiency of midgut α-amylase activity was approximately twofold more than that of the salivary gland enzymes, and was more efficient in digesting soluble starch than glycogen. Midgut α-amylases were developmentally regulated, as one isoform was found in first instar compared to three isoforms in fifth instar nymphs. Starvation significantly affected carbohydrase activities in the midgut, and acarbose inhibited α-amylases from both the salivary glands and midgut in vitro and in vivo. The structural diversity and developmental regulation of carbohydrases in the digestive system of P. maculiventris demonstrate the importance of these enzymes in extra-oral and intra-tract digestion, and may explain the capability of the hemipteran to utilize diverse food sources.

Effects of enzyme supplementation on growth performance, digestibility of phosphorus, femur parameters and fecal microbiota in growing pigs fed different types of diets.

A 42-days study was conducted to evaluate the effects of different dietary types (corn-or wheat-soybean meal-based diet) and phytase (Phy) or a multi-carbohydrase and phytase complex (MCPC) supplementation on growth performance, digestibility of phosphorus (P), intestinal transporter gene expression, plasma indexes, bone parameters, and fecal microbiota in growing pigs. Seventy-two barrows (average initial body weight of 24.70 ± 0.09 kg) with a 2 × 3 factorial arrangement of treatments and main effects of diet type (corn-or wheat-soybean meal-based-diets) and enzyme supplementation (without, with Phy or with MCPC). Each group was designed with 6 replicate pens. The MCPC increased (p < 0.05) average daily gain (ADG) and final body weight (BW). A significant interaction (p = 0.01) was observed between diet type and enzyme supplementation on apparent total tract digestibility (ATTD) of P. The ATTD of P was higher (p < 0.05) in wheat soybean meal-based diets compared to corn-soybean meal-based diets. Compared with the corn-soybean meal-based diet, the relative expression of SLC34A2 and VDR genes in the ileum and SLC34A3 in jejunum of growing pigs fed the wheat-soybean meal based diet was lower (p < 0.05). The MCPC significantly reduced (p < 0.05) the relative expression of TRPV5 and CALB1 genes in the ileum and increased the expression of CALB1 in the duodenum compared to control diet. The phytase increased (p < 0.05) the relative expression of SLC34A1 gene in the duodenum in comparison to control diet and MCPC-supplemented diet. The Ca and P contents in plasma from pigs fed corn-soybean meal-based diet were higher (p < 0.05) than those from pigs fed wheat-soybean meal-based diet, and the parathyroid hormone (PTH) and calcitonin (CT) concentrations were lower (p < 0.05) than those fed wheat-soybean meal-based diet. The content of Ca and P in the femur and the bone strength of pigs in the corn-soybean meal group were significantly higher (p < 0.05) than those in the wheat-soybean meal groups. The phytase increased (p < 0.05) the Ca and P content and bone strength of the femur. Additionally, diet type and both enzymes significantly improved fecal microbial diversity and composition. Taken together, diet type and exogenous enzymes supplementation could differently influence the growth performance, utilization of phosphorus, intestinal transporter gene expression, bone mineralization and microbial diversity and composition in growing pigs.

Efficacy of a novel multi-enzyme feed additive on growth performance, nutrient digestibility, and gut microbiome of weanling pigs fed corn-wheat or wheat-barley-based diet.

One-hundred-and-ninety-two weanling pigs (6.7 kg body weight) were used to evaluate the impact of a carbohydrases-protease enzyme complex (CPEC) on growth performance, nutrient digestibility, and gut microbiome. Pigs were assigned to one of the four dietary treatments for 42 d according to a 2 × 2 factorial arrangement of diet type (low fiber [LF] or high fiber [HF]) and CPEC supplementation (0 or 170 mg/kg diet). The LF diet was prepared as corn-wheat-based diet while the HF diet was wheat-barley-based and contained wheat middlings and canola meal. Each dietary treatment consisted of 12 replicate pens (six replicates per gender) and four pigs per replicate pen. Over the 42-d period, there was no interaction between diet type and CPEC supplementation on growth performance indices of pigs. Dietary addition of CPEC improved (P < 0.05) the body weight of pigs at days 28 and 42 and the gain-to-feed ratio of pigs from days 0 to 14. During the entire experimental period, dietary CPEC supplementation improved (P < 0.05) the average daily gain and gain-to-feed ratio of pigs. There were interactions between diet type and CPEC supplementation on apparent total tract digestibility (ATTD) of dry matter (DM; P < 0.01), gross energy (GE; P < 0.01), and neutral detergent fiber (NDF; P < 0.05) at d 42. Dietary CPEC addition improved (P < 0.05) ATTD of DM, GE, and NDF in the HF diets. At day 43, dietary CPEC addition resulted in improved (P < 0.05) apparent ileal digestibility (AID) of NDF and interactions (P < 0.05) between diet type and CPEC supplementation on AID of DM and crude fiber. Alpha diversity indices including phylogenetic diversity and observed amplicon sequence variants of fecal microbiome increased (P < 0.05) by the addition of CPEC to the HF diets on day 42. An interaction (P < 0.05) between diet type and CPEC addition on Bray-Curtis dissimilarity index and Unweighted UniFrac distances was observed on day 42. In conclusion, CPEC improved weanling pig performance and feed efficiency, especially in wheat-barley diets, while dietary fiber composition had a more significant impact on fecal microbial communities than CPEC administration. The results of this study underscores carbohydrase's potential to boost pig performance without major microbiome changes.

There is a pressing need to enhance livestock production efficiency to meet the growing global demand for meat. Carbohydrases and proteases are enzymes typically added to swine diets to improve nutrient utilization, leading to better growth rates and feed efficiency. This ultimately contributes to sustainable and economically viable pig farming. However, more research is required to better understand how carbohydrases and proteases interact with different diet types to optimize dietary formulations, and how this may influence gut microbiome composition. In this study, 192 weaner pigs (~7 kg) were assigned to a low-fiber diet or a high-fiber diet. Each diet type was with or without a carbohydrases and protease multi-enzyme supplementation. The results showed that adding a multi-enzyme combination to the pigs' diet significantly improved the pig's performance, regardless of diet type. Improvement in nutrient digestibility was more pronounced in pigs fed the high-fiber diet and that dietary fiber had a greater influence on the composition of fecal microbes. In essence, the study demonstrates that the multi-enzyme can boost pig growth and feed efficiency in diets with varying fiber complexity without causing significant changes in their gut microbiome.

Dietary fibre effects and the interplay with exogenous carbohydrases in poultry nutrition.

A comprehensive understanding of the role of dietary fibre in non-ruminant animal production is elusive. Equivocal and conflated definitions of fibre coupled with significant analytical complexity, interact with poorly defined host and microbiome relationships. Dietary fibre is known to influence gut development, feed intake and passage rate, nutrient absorption, microbiome taxonomy and function, gut pH, endogenous nutrient loss, environmental sustainability, animal welfare and more. Whilst significant gaps persist in our understanding of fibre in non-ruminant animal production, there is substantial interest in optimizing the fibre fraction of feed to induce high value phenotypes such as improved welfare, live performance and to reduce the environmental footprint of animal production systems. In order to achieve these aspirational goals, it is important to tackle dietary fibre with the same level of scrutiny as is currently done for other critical nutrient classes such as protein, minerals and vitamins. The chemical, mechanical and nutritional role of fibre must be explored at the level of monomeric sugars, oligosaccharides and polysaccharides of varying molecular weight and decoration, and this must be in parallel to standardisation of analytical tools and definitions for speciation. To further complicate subject, exogenous carbohydrases recognise dietary fibre as a focal substrate and have varying capacity to generate lower molecular weight carbohydrates that interact differentially with the host and the enteric microbiome. This short review article will explore the interactive space between dietary fibre and exogenous carbohydrases and will include their nutritional and health effects with emphasis on functional development of the gut, microbiome modulation and host metabolism.

Heat-induced pressed gels from canola press cakes: Exploring the impact of starting materials, stirring conditions, and carbohydrase pretreatment.

Alternative plant protein sources offer excellent solutions for tackling the current challenge of food insecurity and sustainability. Inspired by soy tofu, pressed gels represent a robust and versatile way to create protein-enriched plant products. Here, production of heat-induced pressed gels from canola cold-pressed cakes (CPC) and hot-pressed cakes (HPC) was investigated under varied stirring conditions. Pressed gels prepared from CPC resulted in a greater yield and protein recovery than that of HPC. While using carbohydrases as a pretreatment was ineffective in improving yield and protein recovery, applying a stirring condition during heating increased the protein recovery up to 38.3%. Also, stirring condition was proved to be able to modulate the textural properties by controlling the compactness and the size of aggregates. It is revealed that pressed gels are stabilized through a combination of hydrogen bonds, hydrophobic interactions, and disulfide bonds. In comparison to canola press cake, the pressed gels contained less glucosinolates and phenolic compounds, but more phytic acid. A mechanism of formation has been hypothesized based on the nucleation-growth mechanism, and a shift was proposed from diffusion-limited processes in non-stirred pressed gels to reaction-limited process in stirred pressed gels. In conclusion, the potential of canola heat-induced pressed gels was demonstrated both as a stand-alone product and a micro-structured protein extract.

Effects of adaptation diet and exogenous enzymes on true metabolizable energy and cecal microbial ecology, short-chain fatty acid profile, and enzyme activity in roosters fed barley and rye diets.

Three experiments evaluated effects of adaptation diet and exogenous ß-glucanase and xylanase on TMEn of barley and rye. Single Comb White Leghorn roosters were fed adaptation diets based on corn/soybean meal (SBM), barley/SBM with and without ß-glucanase, or rye/corn/SBM with and without xylanase for 4 wk. In Experiments 1 and 2, after the adaptation period, TMEn was determined using a 48 h precision-fed rooster assay for 100% barley or 100% rye diets with or without ß-glucanase or xylanase, respectively. Experiment 3 consisted only of feeding adaptation diets for 4 wk. Cecal samples were collected at the end of experiments for microbial ecology, short-chain fatty acid (SCFA) profiles, and enzyme activity analyses. In Experiments 1 and 2, ß-glucanase increased (P < 0.05) TMEn of barley, and there was no significant effect of adaptation diet on TMEn values. Total cecal Eubacteria and Ruminococcaceae were decreased (P < 0.05) and Escherichia coli were increased (P < 0.05) at the end of the TMEn assay compared with the end of the adaptation period (with no TMEn assay). There was a large decrease (P < 0.05) for most cecal SCFA at the end of the TMEn assay compared with the end of the adaptation period. Both cecal ß-glucanase and xylanase activity were increased for birds fed adaptation diets containing the respective enzyme. In Experiment 3, there were no consistent effects of adaptation diet on cecal microbial profiles or SCFA but cecal ß-glucanase activity was increased (P < 0.05) by exogenous ß-glucanase for barley and cecal xylanase activity was increased (P < 0.05) by exogenous xylanase for rye. Overall, the results indicated that TMEn of barley was increased by exogenous ß-glucanase, adaptation diet did not significantly influence the TMEn response to the dietary enzymes, and cecal fermentation (based on cecal SCFA) was greatly reduced by the TMEn assay. Cecal ß-glucanase and xylanase activity, however, were often increased by feeding high barley and high rye diets containing exogenous enzymes.

Digestive α-L-fucosidase activity in Rhodnius prolixus after blood feeding: effect of secretagogue and nutritional stimuli.

Introduction: Rhodnius prolixus (Hemiptera: Reduviidae) is an important vector of Trypanosoma cruzi, the causative agent of Chagas Disease. This insect is a model for the study of insect physiology, especially concerning the digestion of blood. Among the enzymes produced in the midgut of R. prolixus after blood feeding there is a α-L-fucosidase activity. There are very few studies on α-L-fucosidase of insects, and the role of R. prolixus α-L-fucosidase is still not clear. In this work, we tested if the mechanism for production of this enzyme is similar to the observed for proteases, a secretatogue mechanism that respond to the protein contents of the meal. Methods: We tested if specific proteins or sugars elicit this response, which may help to understand the nature of the physiological substrate for this enzyme. Results: In general, our results showed that the Anterior Midgut was the only midgut fraction that responds to the blood meal in terms of α-L-fucosidase production. Besides that, this response was not triggered by midgut distension or by ingestion of the blood cell fraction. Conversely, the enzyme was produced after feeding with the plasma fraction. However, the production of α-L-fucosidase was also triggered by different biochemical stimuli, as protein or fucoidan ingestion. Discussion: This suggested that the production of the enzyme in the anterior midgut was a general physiological response under control of different convergent signals. Besides that, the comparison between different treatments for artificial blood feeding showed that heparinated blood was the choice with minor side effects for the study of the midgut α-L-fucosidase, when compared to defibrinated or citrated blood.