Partially hydrolyzed guar gum as a potential prebiotic source

Enhancing the oral bioavailability of fisetin: polysaccharide-based self nano-emulsifying spheroids for colon-targeted delivery

Fisetin (FS) is a flavonoid that possesses antioxidant and anti-inflammatory properties against ulcerative colitis. FS shows poor dissolution rate and permeability. An attempt has been made to develop colon-targeted solid self-nanoemulsifying drug delivery systems (S-SNEDDS) of FS. Initially, liquid (L) SNEDDS were prepared by loading FS into isotropic mixture of L-SNEDDS was prepared using Labrafil M 1944 CS, Transcutol P, and Tween 80. These L-SNEDDS were further converted into solid (S) SNEDDS by mixing the isotropic mixture with 1:1:1 ratio of guar gum (GG), xanthan gum (XG) and pectin (PC) [GG:XG:PC (1:1:1)]. Aerosil-200 (A-200) was added to enhance their flow characteristics. Further, they were converted into spheroids by extrusion-spheronization technique. The solid-state characterization of S-SNEDDS was done by SEM, DSC, and PXRD, which revealed that the crystalline form of FS was converted into the amorphous form. In the dissolution study, S-SNEDDS spheroids [GG:XG:PC (1:1:1)] exhibited less than 20% drug release within the first 5 h, followed by rapid release of the drug between the 5th and 10th h, indicating its release at colonic site. The site-specific delivery of FS to colon via FS-S-SNEDDS spheroids was confirmed by conducting pharmacokinetic studies on rats. Wherein, results showed delay in absorption of FS loaded in spheroids up to 5 h and achievement of Cmax at 7h, whereas L-SNEDDS showed rapid absorption of FS. Furthermore, FS-L-SNEDDS and FS-S-SNEDDS spheroids [GG:XG:PC (1:1:1)] increased oral bioavailability of FS by 6.86-fold and 4.44-fold, respectively, as compared to unprocessed FS.

Improving Intestinal Barrier Function in Sepsis by Partially Hydrolysed Guar Gum via the Suppression of the NF-κB/MLCK Pathway

Partially hydrolyzed guar gum (PHGG) protects against intestinal barrier dysfunction and can ameliorate some intestinal diseases. However, whether PHGG has a role in protecting intestinal barrier function (IBF) during sepsis remains unclear. This study aimed to investigate the role and probable mechanism of PHGG in the intestinal mucosa in sepsis. A rat sepsis model was constructed using cecal ligation and puncture (CLP). FITC-dextran 4 (FD-4) flux, serum inflammatory mediator levels, tight junction (TJ) levels, jejunum mucosa pathology, and epithelial intercellular junction ultrastructure were monitored to evaluate the effect of PHGG on IBF. Caco-2 monolayers were used to study the impact and mechanism of PHGG on lipopolysaccharide (LPS)-induced barrier dysfunction in vitro. The expression of zonula occludens protein-1 and occludin and the location of P65 were studied by immunofluorescence. Nuclear factor kappa B (NF-κB) and myosin light chain kinase 3 (MLCK) pathway-related protein expression was verified by quantitative reverse transcriptase polymerase chain reaction or western blotting. The results indicated that the jejunal mucosa structure was destroyed, the villi were disrupted and shortened, and neutrophil infiltration was evident in the septic rats. Compared to Sham group, spetic rats had increased Chiu's score, serum inflammatory mediator levels, and FD-4 flux but decreased TJ and gap junction density. In addition, the expression of MLCK, p-MLC, and TJ proteins and the expression of P65 in the nucleus were increased in septic rats. Furthermore, compared to those in the Control group, LPS-treated Caco-2 cells showed lower cell viability and transepithelial electrical resistance, while had higher FD-4 flux and the expression of MLCK, p-MLC, TJ proteins and P65 in the nucleus. PHGG pretreatment reversed the above effects induced by CLP or LPS treatment. Moreover, SN50, an NF-κB inhibitor, attenuated the above effects of LPS on Caco-2 cells. Overall, PHGG reduced inflammation, increased TJ protein expression and localization, and relieved damage to the TJ structure and intestinal permeability through suppression of the NF-κB/MLCK pathway. This study provides new insights into the role of PHGG in sepsis therapy.

Effect of dietary β-mannanase supplementation on broiler performance

This study was conducted to investigate the effect of graded levels of β-mannanase supplementation in broiler diets on growth performance, energy digestibility, and lesion scores in d-old birds fed mash, corn-soybean meal-based diets and raised to 42 d. Five dietary treatments were investigated: 1) positive control diet (PC) containing standard energy; 2) negative control (NC) with 100 kcal/kg diet reduction in AME compared to PC; 3) NC supplemented with 30 U/g β-mannanase (NC + 30 U); 4) NC supplemented with 60 U/g β-mannanase (NC + 60 U); and 5) NC supplemented with 90 U/g β-mannanase (NC + 90 U). Each treatment had 6 replicate pens with 52 chicks per replicate. Data was analyzed using 1-way ANOVA, and means were separated by LSMEANS. Reduction of 100 kcal/kg feed (NC) resulted in an overall body weight gain reduction of 51 g (P < 0.05) and feed conversion loss of approximately 4 points (P < 0.05) compared to PC at 42 d of age. At the same time, supplementing β-mannanase at 60 and 90 U/g improved growth performance parameters compared to NC, while 30 U/g did not result in significant improvements beyond NC; body weight gain was improved (P < 0.05) by 87, and 106 g when β-mannanase was supplemented at 60 and 90 U/g, respectively, compared to NC. This corresponded to an improvement by 6 and 7 points in feed conversion for 60 and 90 U/g supplementation, respectively, compared to NC. Furthermore, AMEn was improved (P < 0.05) by 15, 97, and 116 kcal/kg at 42 d when β-mannanase was added to NC at 30, 60, and 90 U/g, respectively. Digesta viscosity measured at 42 d was decreased (P < 0.05) by β-mannanase supplementation of 60 and 90 U/g, compared to NC, while 42 d lesion scores were improved (P < 0.05) by β-mannanase supplementation compared to NC. Data demonstrated that dietary supplementation of β-mannanase improved growth performance, energy digestibility, and reduced viscosity and lesion scores when supplemented with diets with a reduced energy content of 100 kcal/kg compared to a standard energy diet.

Guar gum as a microbially degradable component for an oral colon delivery system based on a combination strategy: formulation and in vitro evaluation

Oral colon delivery has widely been pursued exploiting naturally occurring polysaccharides degraded by the resident microbiota. However, their hydrophilicity may hinder the targeting performance. The aim of the present study was to manufacture and evaluate a double-coated delivery system leveraging intestinal microbiota, pH, and transit time for reliable colonic release. This system comprised a tablet core, a hydroxypropyl methylcellulose (HPMC) inner layer and an outer coating based on Eudragit® S and guar gum. The tablets were loaded with paracetamol, selected as a tracer drug because of the well-known analytical profile and lack of major effects on bacterial viability. The HPMC and Eudragit® S layers were applied by film-coating. Tested for in vitro release, the double-coated systems showed gastroresistance in 0.1 N HCl followed by lag phases of consistent duration in phosphate buffer pH 7.4, imparted by the HPMC layer and synergistically extended by the Eudragit® S/guar gum one. In simulated colonic fluid with fecal bacteria from an inflammatory bowel disease patient, release was faster than in the presence of β-mannanase and in control culture medium. The bacteria-containing fluid was obtained by an experimental procedure making multiple tests possible from a single sampling and processing run. Thus, the study conducted proved the feasibility of the delivery system and ability of guar gum to trigger release in the presence of colon bacteria without impairing the barrier properties of the coating. Finally, it allowed an advantageous simulated colonic fluid preparation procedure to be set up, reducing the time, costs, and complexity of testing and enhancing replicability.

High-level production of a novel alginate lyase (FsAly7) from Flammeovirga sp. for efficient production of low viscosity soluble dietary fiber from sodium alginate

Sodium alginate is one of the most abundant sustainable gum source for dietary fiber production. However, the preparation efficiencies of low viscosity soluble dietary fiber from sodium alginate remain low. Here, a novel alginate lyase gene (FsAly7) from Flammeovirga sp. was identified and high-level expressed in Pichia pastoris for low viscosity soluble dietary fiber production. The highest enzyme production of 3050 U mL-1 was achieved, which is by far the highest yield ever reported. FsAly7 was used for low viscosity soluble dietary fiber production from sodium alginate, and the highest degradation rate of 85.5 % was achieved under a high substrate content of 20 % (w/v). The molecular weight of obtained soluble dietary fiber converged to 10.75 kDa. FsAly7 catalyzed the cleavage of glycosidic bonds in alginate chains with formation of unsaturated non-reducing ends simultaneously in the degradation process, thus altered the chemical structures of hydrolysates. The soluble dietary fiber exhibited excellent properties, including low viscosity, high oil adsorption capacity activity (2.20 ± 0.03 g g-1) and high emulsifying activity (60.05 ± 2.96 mL/100 mL). This investigation may provide a novel alginate lyase catalyst as well as a solution for the efficient production of low viscosity soluble dietary fiber from sodium alginate.

Carbohydrases and Phytase in Poultry and Pig Nutrition: A Review beyond the Nutrients and Energy Matrix

This review aimed to clarify the mechanisms through which exogenous enzymes (carbohydrases and phytase) influence intestinal health, as well as their effects on the nutrients and energy matrix in diets fed to poultry and pigs reared under sanitary challenging conditions. Enzyme supplementation can positively affect intestinal microbiota, immune system, and enhance antioxidant status. Although enzymes have been shown to save energy and nutrients, their responses under sanitary challenging conditions are poorly documented. Immune system activation alters nutrient partitioning, which can affect the matrix values for exogenous enzymes on commercial farms. Notably, the carbohydrases and phytase supplementation under sanitary challenging conditions align with energy and nutritional valorization matrices. Studies conducted under commercial conditions have shown that matrices containing carbohydrases and phytase can maintain growth performance and health in poultry and pigs. However, these studies have predominantly focused on assessing a single level of reduction in energy and/or available phosphorus and total calcium, limiting our ability to quantify potential energy and nutrient savings in the diet. Future research should delve deeper into determining the extent of energy and nutrient savings and understanding the effects of alone or blended enzymes supplementation to achieve more specific insights.

Exploring the partial degradation of polysaccharides: Structure, mechanism, bioactivities, and perspectives

Polysaccharides are promising biomolecules with lowtoxicity and diverse bioactivities in food processing and clinical drug development. However, an essential prerequisite for their applications is the fine structure characterization. Due to the complexity of polysaccharide structure, partial degradation is a powerful tool for fine structure analysis, which can effectively provide valid information on the structure of backbone and branching glycosidic fragments of complex polysaccharides. This review aims to conclude current methods of partial degradation employed for polysaccharide structural characterization, discuss the molecular mechanisms, and describe the molecular structure and solution properties of degraded polysaccharides. In addition, the effects of polysaccharide degradation on the conformational relationships between the molecular structure and bioactivities, such as antioxidant, antitumor, and immunomodulatory activities, are also discussed. Finally, we summarize the prospects and current challenges for the partial degradation of polysaccharides. This review will be of great value for the scientific elucidation of polysaccharide fine structures and potential applications.

Gut firmicutes: Relationship with dietary fiber and role in host homeostasis

Firmicutes and Bacteroidetes are the predominant bacterial phyla colonizing the healthy human gut. Accumulating evidence suggests that dietary fiber plays a crucial role in host health, yet most studies have focused on how the dietary fiber affects health through gut Bacteroides. More recently, gut Firmicutes have been found to possess many genes responsible for fermenting dietary fiber, and could also interact with the intestinal mucosa and thereby contribute to homeostasis. Consequently, the relationship between dietary fiber and Firmicutes is of interest, as well as the role of Firmicutes in host health. In this review, we summarize the current knowledge regarding the molecular mechanism of dietary fiber degradation by gut Firmicutes and explain the communication pathway of the dietary fiber-Firmicutes-host axis, and the beneficial effects of dietary fiber-induced Firmicutes and their metabolites on health. A better understanding of the dialogue sustained by the dietary fiber-Firmicutes axis and the host could provide new insights into probiotic therapy and novel dietary interventions aimed at increasing the abundance of Firmicutes (such as Faecalibacterium, Lactobacillus, and Roseburia) to promote health.

Metabolic response of intestinal microbiota to guar gum consumption

Background

Guar gum is used extensively as a thickening agent in food, but it remains uncertain whether and to what extent it is fermented by colonic microbiota and whether it has microbiota modulatory properties.

Aim

To determine the metabolic response of intestinal microbiota to guar gum consumption, specifically, the extent of initial fermentation and subsequent adaptation.

Methods

Single-center, single arm, open label, proof-of-concept study testing the effect of guar gum on microbiota metabolism and adaptation. Healthy male subjects (n = 12) were administered gum guar (8 g/day) for 18 days. Outcomes were measured before, at initial and late administration: (a) anal gas evacuations (number/day); (b) digestive sensations (daily scales); and (c) fecal gut microbiota taxonomy and metabolic functions by shotgun sequencing.

Results

At initial consumption, guar gum induced a transient increase in anal gas evacuations and digestive sensations; gas evacuation completely reverted upon continuous administration, whereas sensations reverted only in part. Guar gum induced moderate changes in human microbiota composition at both taxonomic and functional levels. Positive associations between effects on microbiota (proliferation of Agathobaculum butyriciproducens and Lachnospira pectinoschiza) and hedonic sensations were detected.

Conclusion

Guar gum is metabolized by intestinal microbiota, and, upon continuous consumption, induces a selective adaptation of microbial taxonomy and function. These data highlight the potential interest of guar gum for novel prebiotic ingredient formulation.

Effects of partially hydrolyzed guar gums of different molecular weights on a human intestinal in vitro fermentation model

Partially hydrolyzed guar gums (PHGGs) are prebiotic soluble dietary fibers. High molecular-weight PHGGs have rapid fermentation and high short-chain fatty acid (SCFA) productivity rates, compared to low molecular-weight PHGGs. Therefore, low molecular-weight PHGGs may have less pronounced prebiotic effects than high molecular-weight PHGGs. However, the effects of PHGGs of different molecular weights on the human intestinal microbiota, as well as their fermentation ability and prebiotic effects, have not been investigated. The aim of this study was to evaluate the effects of two PHGGs of different molecular weights, Sunfiber-R (SF-R; 20 kDa) and Sunfiber-V (SF-V; 5 kDa), on human colonic microbiota and SCFA production. A human intestinal in vitro fermentation model was operated by fecal samples with and without the PHGGs. The addition of 0.2% SF-R or SF-V increased the relative abundance of Bacteroides spp., especially that of Bacteroides uniformis. This increase corresponded to a significant (p = 0.030) and non-significant (p = 0.073) increase in propionate production in response to SF-R and SF-V addition, respectively. Both fibers increased the relative abundance of Faecalibacterium and stimulated an increase in the abundance of unclassified Lachnospiraceae and Bifidobacterium. In conclusion, the low molecular-weight PHGG exerted prebiotic effects on human colonic microbiota to increase SCFA production and bacteria that are beneficial to human health in a manner similar to that of the high molecular-weight forms of PHGG.

Effect of partially hydrolyzed guar gum on the composition and metabolic function of the intestinal flora of healthy mice

Partially hydrolyzed guar gum (PHGG), a water-soluble dietary fiber, has shown beneficial physiological effects in various disease models and is used as a prebiotic to regulate intestinal function. However, its role in healthy states remains unclear. The purpose of this study was to investigate the effects of PHGG on gut flora composition and predict metabolic function in healthy mice. Our study showed that PHGG supplementation had significant duration-dependent effects on the composition and function of the intestinal flora of healthy mice. In specific, although the long-term supplementation of PHGG may increase the abundance of some beneficial bacterial species and promote beneficial phenotypes, it may also cause increased body weight and decreased abundance and diversity of gut microorganisms. Therefore, the long-term use of PHGG as a nutritional product still requires further investigation. PRACTICAL APPLICATIONS: As the importance of the gut microbiota has become more widely recognized, interventions that modulate the microbiome and its interaction with the host have gained much attention. While the capability of some prebiotics has largely been shown to have many beneficial effects, the evidence leaves much desirable, and microbiota regulation is explored differently in healthy or diseased states. Currently, the scientific community and regulatory authorities are beginning to pay attention to these unregulated and over-the-counter products claiming to possess probiotic and prebiotic properties. Studies exploring the rationality of these prebiotics as nutraceuticals for use in health states are essential. This study focuses on the effects of PHGG, a prebiotic, on intestinal flora, metabolism, and function when used in a healthy state over a long period. It is helpful to have a clearer understanding of the effect of PHGG on intestinal flora and the possible mechanisms of action to exert effects, which are indicative for the future application of PHGG as a nutraceutical or therapeutic agent..

Does supplementing β-mannanase modulate the feed-induced immune response and gastrointestinal ecology in poultry and pigs? An appraisal

The provision of adequate and balanced nutrients is critical for efficient and profitable animal protein production. However, non-nutritive components in feedstuffs can elicit responses that can negatively impact nutrient utilization efficiency. For example, dietary β-mannans are recognizable by cell surface mannose receptors are pivotal for diverse cellular functions. This review will evaluate the physiological implications of dietary native β-mannans, the utility of supplemental feed β-mannanase in hydrolyzing β-mannans, and subsequent metabolic responses. Dietary native β-mannans have been implicated in inadvertent stimulation of immune response through a phenomenon called the feed-induced immune response (FIIR), that has been associated with intestinal inflammation and depression in animal performance. Supplemental β-mannanase blunted the FIIR by hydrolyzing native β-mannans to smaller fragments with a reduced ability to stimulate the innate immune system as indicated by the modulation of oxidative stress, mucosal permeability, and blood concentration of acute phase proteins and immunoglobulins in broilers and piglet models. Moreover, β-mannanase hydrolysis of native β-mannans to mannooligosaccharides (MOS) impacted gastrointestinal microbial ecology. Indeed, β-mannanase-derived MOS reduced the concentration of pathogenic bacteria such as Escherichia coli and Salmonella and increased the production of short-chain fatty acids in gastrointestinal tracts of various animal models. Consequently, by hydrolyzing native β-mannans, supplemental β-mannanase may have nutritional, metabolic, and microbial ecology benefits. In summary, integrating multi-functional feed additives such as β-mannanase into feeding programs for monogastric animals will be critical for efficient and sustainable animal protein production in the context of evolving challenges such as the mandated elimination of use of antibiotics for growth promotion.

Structural Characterization and Functional Properties of Flaxseed Hydrocolloids and Their Application

Flaxseed is an excellent source of valuable nutrients and is also considered a functional food. There are two types of hydrocolloids in flaxseed: flaxseed gum and proteins. Flaxseed gum exhibits emulsifying and foaming activities or can be used as a thickening and gelling agent. Due to its form of soluble fiber, flaxseed gum is related to many health benefits. Flaxseed proteins have various functional properties based on their physicochemical properties. While albumins possess the emulsion-forming ability, globulins better serve as foaming agents. Flaxseed proteins may also serve as a source of functional peptides with interesting biological and health-related activities. Functional properties and health-related benefits predetermine the application of these hydrocolloids, mainly in the food industry or medicine. Although these properties of flaxseed hydrocolloids have been recently and extensively studied, they are still not widely used on the industrial scale compared to other popular plant gums and proteins. The aim of this review was to present, discuss and highlight the recent discoveries in the structural characteristics and functional and biological properties of these versatile hydrocolloids with respect to factors affecting their characteristics and offer new insights into their potential applications as comparable alternatives to the other natural hydrocolloids or as the sources of novel functional products.

Dietary fiber in bakery products: Source, processing, and function

Bakery products are prevalently consumed foods in the world, and they have been regarded as convenient dietary vehicles for delivering nutritive ingredients into people's diet, of which, dietary fiber (DF) is one of the most popular items. The food industry attempts to produce fiber-enriched bakery products with both increasing nutritional value and appealing palatability. As many new sources of DFs become available, and consumers are moving towards healthier diets, studies of using these DFs as functional ingredients in baked goods are becoming vast. Besides, the nutrition value of DF is commonly accepted, and many investigations have also revealed the health benefits of fiber-enriched bakery products. Thus, this chapter presents an overview of (1) trends in supplementation of DF from various sources, (2) impact of DF on dough processing, quality and physiological functionality of bakery products, and (3) technologies used to improve the compatibility of DF in bakery products.

Recent development in fabrication and evaluation of phenolic-dietary fiber composites for potential treatment of colonic diseases

Phenolics have been shown by in vitro and animal studies to have multiple pharmacological effects against various colonic diseases. However, their efficacy against colonic diseases, such as inflammatory bowel diseases, Crohn's disease, and colorectal cancer, is significantly compromised due to their chemical instability and susceptibility to modification along the gastrointestinal tract (GIT) before reaching the colonic site. Dietary fibers are promising candidates that can form phenolic-dietary fiber composites (PDC) to carry phenolics to the colon, as they are natural polysaccharides that are non-digestible in the upper intestinal tract but can be partially or fully degradable by gut microbiota in the colon, triggering the release at this targeted site. In addition, soluble and fermentable dietary fibers confer additional health benefits as prebiotics when used in the PDC fabrication, and the possibility of synergistic relationship between phenolics and fibers in alleviating the disease conditions. The functionalities of PDC need to be characterized in terms of their particle characteristics, molecular interactions, release profiles in simulated digestion and colonic fermentation to fully understand the metabolic fate and health benefits. This review examines recent advancements regarding the approaches for fabrication, characterization, and evaluation of PDC in in vitro conditions.

Effects of Partially Hydrolyzed Guar Gum Supplementation on the Fecal Microbiotas of Piglets

Probiotics and prebiotics have become viable alternatives of growth-promoting antimicrobials in animal production. Here, we tested partially hydrolyzed guar gum (PHGG) as a possible prebiotic for piglets in the commercial farm. Five hundred and ninety-four piglets were used for the experiments, with 293 given a normal pig feed (control), while the rest the feed plus 0.06% (w/w) of PHGG (PHGG). One and three months post-PHGG supplementation, fecal samples were collected from randomly selected 20 piglets in each group and analyzed for microbiota and organic acid concentrations. Notably, the abundance of Streptococcus, and unclassified Ruminococcaceae were lower (p < 0.05) in PHGG than in control, one-month post-supplementation. Lactobacillus and Prevotella were higher (p < 0.05), while Streptococcus was lower (p < 0.05), in PHGG than in control, three months post-supplementation. The concentrations of acetate, propionate, and butyrate were greater in PHGG than in control, three months post-supplementation. Finally, PHGG grew faster and had fewer deaths until slaughter time (p < 0.05), than control. We concluded that PHGG not only was an effective prebiotic to alter gut microbiota of weanling piglets but also can possibly promote body weight accretion and health.

Celecoxib repurposing in cancer therapy: molecular mechanisms and nanomedicine-based delivery technologies

While cancer remains a significant global health problem, advances in cancer biology, deep understanding of its underlaying mechanism and identification of specific molecular targets allowed the development of new therapeutic options. Drug repurposing poses several advantages as reduced cost and better safety compared with new compounds development. COX-2 inhibitors are one of the most promising drug classes for repurposing in cancer therapy. In this review, we provide an overview of the detailed mechanism and rationale of COX-2 inhibitors as anticancer agents and we highlight the most promising research efforts on nanotechnological approaches to enhance COX-2 inhibitors delivery with special focus on celecoxib as the most widely studied agent for chemoprevention or combined with chemotherapeutic and herbal drugs for combating various cancers.

Structure characterization and in vitro hypoglycemic effect of partially degraded alginate

Alginate is a low-cost polysaccharide found abundantly in seaweeds which consists of mannuronate and guluronate, and it is considered a sustainable gum source for dietary fiber. To solve the high viscosity-related problems while retaining its physiological properties, four partially degraded alginate products (PDA1-4) with molecular weight of 1.05-0.40 × 10⁵ g mol^-1 and intrinsic viscosity of 170.9-38.9 mL g^-1 were enzymatically prepared and characterized. ¹H Nuclear magnetic resonance analysis showed the used alginate lyase had a preference to degrade guluronate-blocks. PDA1 and PDA2 presented random coil conformation, whereas PDA3 and PDA4 displayed compact spherical-coil conformation over random coil conformation in solution. In vitro assays suggested a glucose-adsorption capacity order of PDA1 < PDA2 < alginate < PDA3 < PDA4 and a glucose-diffusion retardation capacity order of PDA3 < PDA1 ≤ alginate < PDA2 < PDA4, indicating that partially degraded alginate reinforced the hypoglycemic effect, especially mannuronate-rich PDA4. Overall, the study may have important implications for development of PDA as dietary fiber with potential hypoglycemic activity.

Plant Prebiotics and Their Role in the Amelioration of Diseases

Prebiotics are either natural or synthetic non-digestible (non-)carbohydrate substances that boost the proliferation of gut microbes. Undigested fructooligosaccharides in the large intestine are utilised by the beneficial microorganisms for the synthesis of short-chain fatty acids for their own growth. Although various food products are now recognized as having prebiotic properties, several others, such as almonds, artichoke, barley, chia seeds, chicory, dandelion greens, flaxseeds, garlic, and oats, are being explored and used as functional foods. Considering the benefits of these prebiotics in mineral absorption, metabolite production, gut microbiota modulation, and in various diseases such as diabetes, allergy, metabolic disorders, and necrotising enterocolitis, increasing attention has been focused on their applications in both food and pharmaceutical industries, although some of these food products are actually used as food supplements. This review aims to highlight the potential and need of these prebiotics in the diet and also discusses data related to the distinct types, sources, modes of action, and health benefits.

Molar mass effect in food and health

It is demanded to supply foods with good quality for all the humans. With the advent of aging society, palatable and healthy foods are required to improve the quality of life and reduce the burden of finance for medical expenditure. Food hydrocolloids can contribute to this demand by versatile functions such as thickening, gelling, stabilising, and emulsifying, controlling texture and flavour release in food processing. Molar mass effects on viscosity and diffusion in liquid foods, and on mechanical and other physical properties of solid and semi-solid foods and films are overviewed. In these functions, the molar mass is one of the key factors, and therefore, the effects of molar mass on various health problems related to noncommunicable diseases or symptoms such as cancer, hyperlipidemia, hyperglycemia, constipation, high blood pressure, knee pain, osteoporosis, cystic fibrosis and dysphagia are described. Understanding these problems only from the viewpoint of molar mass is limited since other structural characteristics, conformation, branching, blockiness in copolymers such as pectin and alginate, degree of substitution as well as the position of the substituents are sometimes the determining factor rather than the molar mass. Nevertheless, comparison of different behaviours and functions in different polymers from the viewpoint of molar mass is expected to be useful to find a common characteristics, which may be helpful to understand the mechanism in other problems.

High-efficiency expression of a superior β-mannanase engineered by cooperative substitution method in Pichia pastoris and its application in preparation of prebiotic mannooligosaccharides

β-mannanase with high specific activity is a prerequisite for the industrial preparation of prebiotic mannooligosaccharides. Three mutants, namely MEI, MER, and MEIR, were constructed by cooperative substitution based on three predominant single-point site mutations (K291E, L211I, and Q112R, respectively). Heterologous expression was facilitated in Pichia pastoris and the recombinase was characterized completely. The specific activities of MER (7481.9 U mg^-1) and MEIR (9003.1 U mg^-1) increased by 1.07- and 1.29-fold from the initial activity of ME (6970.2U mg^-1), respectively. MEIR was used for high-cell-density fermentation to further improve enzyme activity, and the expression levels achieved in the 10-L fermenter were significantly high (105,836 U mL^-1). The prebiotic mannooligosaccharides (<2000 Da) were prepared by hydrolyzing konjac gum and locust bean gum with MEIR, with 100% and 76.40% hydrolysis rates, respectively. These characteristics make MEIR highly attractive for prebiotic development in food and related industries.

Developing novel synbiotic low-fat yogurt with fucoxylogalacturonan from tragacanth gum: Investigation of quality parameters and Lactobacillus casei survival

Tragacanth gum (TG) displayed a prebiotic activity, but its application was restricted due to high viscosity and deterioration of organoleptic and textural characteristics of food. In this study, TG was depolymerized by Pectinex Ultra Color enzyme followed by membrane separation (30 kDa) to get pectinase hydrolyzed fraction of tragacanth gum (PHFTG) with molecular weight more than 30 kDa. The average molecular weight of PHFTG was 147.7 ± 11.5 g/mol having a fucoxylogalacturonan structure. The prebiotic activity was tested using PHFTG, TG, and inulin as a carbon source. The results showed that the count of Lactobacillus casei in PHFTG- and inulin-supplemented media increased significantly during the 48-hr fermentation (p < .05). Five batches of low-fat set yogurts were prepared by the following formulation: Control (without both L. casei and prebiotic), LC-Cont (containing L. casei), LC-PHFTG (containing L. casei + 0.5% PHFTG), LC-TG (containing L. casei + 0.05% TG), and LC-In (containing L. casei + 0.5% inulin), and L. casei population and physicochemical properties were monitored during 21-day storage at 4°C. The number of L. casei remained highly acceptable (8.54-8.61 log CFU/g) during 7-21 days of storage in LC-PHFTG. LC-In and LC-PHFTG presented significantly lower syneresis and higher sensory acceptability than LC-Cont and Control during storage (p < .05). LC-TG displayed weaker body and texture, lower sensory acceptability, and higher syneresis than other samples. This study provides support for expanding the utilization of PHFTG as a potential prebiotic and fat replacer in non- or low-fat dairy products with satisfactory sensory quality.

Isolation, physical, structural characterization and in vitro prebiotic activity of a galactomannan extracted from endosperm splits of Chinese Sesbania cannabina seeds

The purpose of this study was to identify and determine the physical and structural characterization of the water-soluble galactomannan extracted from endosperm splits of Chinese S. cannabina seeds. The Sesbania galactomannan (SP) was extracted and purified using a novel method with a high yield (40.3 ± 7.2%). The molecular structure of SP was determined by monosaccharide composition, FTIR and NMR spectroscopy. The structural data showed that SP was galactomannan which composed by a β-(1/4)-linked mannose backbone with galactopyranosyl residues attached through α-(1/6) linkages. The constant mannose/galactose (M/G) ratio and average molecular weight (M_w) of SP was 1.6:1 and 2.16 × 10⁵ g/mol, respectively. The physical results revealed that SP had many branches on the backbone and existed as a random coil state in aqueous solution. SP was a good biopolymer which had smooth and clearer surface with homogeneous composition, and had some degree of crystallinity and prebiotic activity. As a consequence, SP could be a potential prebiotic and was expected to be suitable for applications in food, pharmaceutical, biomedical or cosmetic industries as a promising new biomaterial.

Properties of hydrolyzed guar gum fermented in vitro with pig fecal inocula and its favorable impacts on microbiota

In order to identify an appropriate substitute for antibiotic use in livestock production, this study investigates the fermentation of guar gum and its low molecular weight hydrolyzed derivatives (GMLP-1, 1-10 kDa; GMLP-2, < 1 kDa) in pig fecal cultures and the associated effects on the intestinal microbiota. Both the non-hydrolyzed guar gum and GMLP were quickly utilized by fecal microbiota. GMLP-2 showed the most rapid SCFA-producing activity and produced higher concentrations of lactate, acetate, and propionate. However, GMLP-1 showed the highest yield of total SCFAs and butyrate. Both the guar gum and GMLP groups improved the abundance of Clostridium sensu stricto 1 and Bifidobacterium, but the most significant enhancement was observed with GMLP-1. This study showed that by associating with its chemical structure, GMLP-1 can be utilized to direct a targeted promotion of the intestinal microbiota and may offer the most favorable effects in livestock production.

The effect of preoperative synbiotic treatment to prevent surgical-site infection in hepatic resection

We aimed to clarify the influence of preoperative synbiotic therapy on surgical-site infections (SSIs) after hepatic resection. Between January 2011 and December 2017, 284 patients who underwent hepatic resection without biliary tract reconstruction and resection of other organs were included. We prospectively administered Clostridium butyricum and partially hydrolyzed guar gum before hepatic resection between April 2016 and December 2017 (synbiotic group). One-hundred-fifteen patients of the synbiotic group and 169 patients (conventional group) treated between January 2011 and the end of March 2016 were compared using propensity score matching. The frequency of laparoscopic resection was significantly larger in the synbiotic group (conventional group; 28% vs synbiotic group; 55%, p<0.001) and the amount of intraoperative bleeding was significantly smaller in the synbiotic group (median; conventional group, 700 ml vs synbiotic group, 200 ml; p<0.001). The postoperative SSI was significantly lower in the synbiotic group of six patients (5.2%) than in the conventional group of 30 patients (17.8%) (p = 0.002). Sixty patients in each group remained after propensity score matching. There was no significant difference in the incidence of SSI between the groups (conventional group, 15% vs synbiotic group, 6.7%; p = 0.239). In conclusion, preoperative synbiotic treatment did not reduce SSIs after hepatic resection.

Synthesis, characterization, and antimicrobial efficacy of composite films from guar gum/sago starch/whey protein isolate loaded with carvacrol, citral and carvacrol-citral mixture

The aim of this research was to formulate antimicrobial, composite films of guar gum, sago starch, and whey protein isolate for the prophylaxis of the bacterial gastroenteritis. The model antibacterial agents incorporated were essential oils, namely, carvacrol, citral and their combination. The films became darker and brownish in color due to the entrapment of the oils. The surface of the oil-entrapped films was more rough and coarse compared to the control film. Confocal micrographs affirmed the uniform distribution of the oil droplets within the biopolymeric network. The highest crystallite size and lowest lattice strain were estimated in the citral-containing film. FTIR analysis demonstrated that the incorporation of citral increased the proportion of the β-sheet structures of the whey protein isolate within the film matrix. However, the film formulation containing combination of carvacrol and citral demonstrated the lowest water vapor transmission rate (WVTR), highest tensile strength, Young's modulus and work to failure. All the oil-containing films demonstrated good antibacterial potency against the model bacterial gastroenteritis causing bacteria, namely, Bacillus cereus and Escherichia coli. In gist, it can be concluded that the prepared antimicrobial films could be used for the prophylaxis of the bacterial gastroenteritis.

Influence of ultrasound irradiation on the intrinsic viscosity of guar gum-PEG/rosin glycerol ester nanoparticles

Novel Guar Gum (GG) and polyethylene glycol (PEG) polymer blends with rosin glycerol ester (RE) nanoparticle was synthesized under ultrasonic irradiation at different composition ratios (1:1, 1:2, 1:4, 2:1, and 4:1). The intrinsic viscosities of the nanoparticles were investigated using ultrasound irradiation to determine the miscibility of the blends in solution as affected by salt, sonication time, temperature, and pH. The intrinsic viscosities of the nanosystems were compared with five different models, including Huggins, Kraemer, Tanglertpaibul-Rao, Higiro, and Rao. The Tanglertpaibul-Rao was the best model and the intrinsic viscosities of 138,27, 142,94 and 163,29 dl/g were reported for GG-PEG/RE (1:1,1:2,1:4), respectively. The viscosity results reveal that the blend containing 1:2 (GG-PEG/RE) was an optimum miscible blend. The miscibility behaviour of the polymeric nanoparticles was investigated using the voluminosity (VE), shape factor (υ), creaming index (CI) parameter, and the Krigbaum and Wall parameter (Δb), which account for the intermolecular interactions. When compared to the intrinsic viscosity results of the nanoparticles, the miscibility-improving effect of sub-300 nm GG-PEG/RE nanoparticles is clearly proven due to the ultrasonic effect. Scanning transmission electron microscopy (STEM) and Fourier transformed infrared (FTIR) spectroscopy were used for characterization of the polymeric nanoparticles.

"Dietary fibre": moving beyond the "soluble/insoluble" classification for monogastric nutrition, with an emphasis on humans and pigs

This review describes dietary fibres originating from a range of foods, particularly in relation to their plant cell walls. It explores the categorization of dietary fibres into “soluble” or “insoluble”. It also emphasizes dietary fibre fermentability, in terms of describing how the gastro-intestinal tract (GIT) microbiota respond to a selection of fibres from these categories. Food is categorized into cereals, legumes, fruits and vegetables. Mention is also made of example whole foods and why differences in physico-chemical characteristics between “purified” and “non-purified” food components are important in terms of health. Lastly, recommendations are made as to how dietary fibre could be classified differently, in relation to its functionality in terms of fermentability, rather than only its solubility.

Hepatoprotective Potential of Partially Hydrolyzed Guar Gum against Acute Alcohol-Induced Liver Injury in Vitro and Vivo

Natural polysaccharides, particularly galactomannans, are potential candidates for treatment of alcoholic liver diseases (ALD). However, applications are restricted due to the physicochemical properties associated with the high molecular weight. In this work, guar gum galactomannans were partially hydrolyzed by β-mannanase, and the molecular mechanisms of hepatoprotective effects were elucidated both in vitro and in vivo. Release of lactate dehydrogenase and cytochrome C were attenuated by partially hydrolyzed guar gum (PHGG) in HepG2 cells, due to protected cell and mitochondrial membrane integrity. PHGG co-administration decreased serum amino transaminases and cholinesterase levels of acute alcohol intoxicated mice, while hepatic pathologic morphology was depleted. Activity of superoxide dismutase, catalase, and glutathione peroxidase was recovered to 198.2, 34.5, 236.0 U/mg protein, respectively, while malondialdehyde level was decreased by 76.3% (PHGG, 1000 mg/kg∙day). Co-administration of PHGG induced a 4.4-fold increment of p-AMPK expression, and lipid metabolism was mediated. PHGG alleviated toll-like-receptor-4-mediated inflammation via the signaling cascade of MyD88 and IκBα, decreasing cytokine production. Moreover, mediated expression of Bcl-2 and Bax was responsible for inhibited acute alcohol-induced apoptosis with suppressed cleavage of caspase 3 and PARP. Findings gained suggest that PHGG can be used as functional food supplement for the treatment of acute alcohol-induced liver injury.

Nano-scale polysaccharide materials in food and agricultural applications

Potential applications of nanotechnology in food and agriculture include: (1) the encapsulation of functional compounds; (2) production of reinforcing materials; (3) delivery of nutraceuticals in foods; (4) food safety, for detection and control of chemical and microbiological risks; (5) active and intelligent food packaging; (6) incorporation of protective substances of seeds; (7) addition of nutrients in the soil; (8) use of controlled release pesticides. Natural polysaccharides and their derivatives are widely used in the production of nano-scale materials. This chapter examines, the use of polysaccharides, such as starch, cellulose, lignin, pectin, gums, and cyclodextrins for the production of nano-scale materials, including nanocrystals, nanoemulsions, nanocomplexes, nanocapsules, and nanofibers.

Mannans: An overview of properties and application in food products

This review aims to emphasize the occurrence and abundant presence of mannans in nature, their classification, structural differences and significance in food and feed industry. With rising demand from the consumers' end for novel natural foods, usage of galactomannan and glucomannan has also increased alternatively. Non toxicity of mannans permits their usage in the pharmaceutical, biomedical, cosmetics, and textile industries. In the food industry, mannans have various applications such as edible films/coating, gel formation, stiffeners, viscosity modifiers, stabilizers, texture improvers, water absorbants, as prebiotics in dairy products and bakery, seasonings, diet foods, coffee whiteners etc. Applications and functions of these commonly used commercially available mannans have therefore, been highlighted. Mannans improve the texture and appeal of food products and provide numerous health benefits like controlling obesity and body weight control, prebiotic benefits, constipation alleviaton, prevent occurrence of diarrhea, check inflammation due to gut related diseases, management of diverticular disease management, balance intestinal microbiota, immune system modulator, reduced risk of colorectal cancer etc. Mannan degrading enzymes are the key enzymes involved in degradation and are useful in various industrial processes such as fruit juice clarification, viscosity reduction of coffee extracts etc. besides facilitating the process steps and improving process quality.