Showing papers on "Guar gum published in 2015"

Gluten free biscuits prepared from buckwheat flour by incorporation of various gums: Physicochemical and sensory properties

Abstract: Gluten-free bakery foodstuffs are a challenge for technologists and nutritionists because of difficulty in creating them and these are very much required for people suffering from celiac disease or for those intolerant or allergic to gluten. Buckwheat flour (BWF) was chosen as a gluten free source as this has been reported to have various polyphenolic compounds with antioxidant activity resulting in health benefits. Quality properties of BWF were compared with refined wheat flour (WF) and gums (guar gum, gum acacia, xanthan and gum tragacanth) were added in the concentration of 1 g/100 g to BWF. Incorporation of gums to BWF significantly (p

Effect of guar gum and xanthan gum on pasting and noodle-making properties of potato, corn and mung bean starches

Abstract: The effect of xanthan and guar-gum on pasting and noodle-making properties of potato, corn and mung bean starches was studied. Mung bean starch showed the highest amylose content (43.4 %) followed by potato (23.2 %) and corn starch (15.5 %). Potato starch showed the highest swelling power (19.0 g/g) and solubility index (17.5 %) and exhibited the highest paste viscosities. Addition of both gums improved peak viscosity, hot paste viscosity and final viscosity for mung and corn starches; while for potato starch, guar gum increased peak and final viscosities and decreased hot paste viscosity while xanthan gum increased hot paste and final viscosities and decreased peak viscosity. The noodles made from mung bean starch showed the most desirable characteristics in terms of the lowest-cooking loss and adhesiveness. The gums increased noodle cooking time and decreased cooking loss, firmness and cohesiveness.

Protection against the Metabolic Syndrome by Guar Gum-Derived Short-Chain Fatty Acids Depends on Peroxisome Proliferator-Activated Receptor γ and Glucagon-Like Peptide-1.

Abstract: The dietary fiber guar gum has beneficial effects on obesity, hyperglycemia and hypercholesterolemia in both humans and rodents. The major products of colonic fermentation of dietary fiber, the short-chain fatty acids (SCFAs), have been suggested to play an important role. Recently, we showed that SCFAs protect against the metabolic syndrome via a signaling cascade that involves peroxisome proliferator-activated receptor (PPAR) γ repression and AMP-activated protein kinase (AMPK) activation. In this study we investigated the molecular mechanism via which the dietary fiber guar gum protects against the metabolic syndrome. C57Bl/6J mice were fed a high-fat diet supplemented with 0% or 10% of the fiber guar gum for 12 weeks and effects on lipid and glucose metabolism were studied. We demonstrate that, like SCFAs, also guar gum protects against high-fat diet-induced metabolic abnormalities by PPARγ repression, subsequently increasing mitochondrial uncoupling protein 2 expression and AMP/ATP ratio, leading to the activation of AMPK and culminating in enhanced oxidative metabolism in both liver and adipose tissue. Moreover, guar gum markedly increased peripheral glucose clearance, possibly mediated by the SCFA-induced colonic hormone glucagon-like peptide-1. Overall, this study provides novel molecular insights into the beneficial effects of guar gum on the metabolic syndrome and strengthens the potential role of guar gum as a dietary-fiber intervention.

Development and characterization of guar gum nanoparticles for oral immunization against tuberculosis

Abstract: The main aim of this study was to develop an effective carrier system containing Ag85A-loaded guar gum nanoparticles for oral vaccination against tuberculosis. Nanoparticles were prepared by Nanoprecipitation method. The developed particles with mean diameter 895.5 ± 14.73 nm and high antigen entrapment seem to be optimum for oral vaccine delivery. The acid protection assay, Peyer’s patch uptake study and in-vitro antigen study confirmed that the developed formulations can protect the antigen from harsh gastric environment and can safely deliver the antigen to the intestinal region. In vivo studies data indicated that the developed nanocarriers can induce a strong mucosal as well as systemic immune response. Therefore, the experimental evidence suggests that guar-gum nanoparticle findings indicated that the guar gum nanoparticles can be utilized for safe and effective vaccine delivery via oral route.

The physico-chemical properties of dietary fibre determine metabolic responses, short-chain Fatty Acid profiles and gut microbiota composition in rats fed low- and high-fat diets.

Abstract: The aim of this study was to investigate how physico-chemical properties of two dietary fibres, guar gum and pectin, affected weight gain, adiposity, lipid metabolism, short-chain fatty acid (SCFA) profiles and the gut microbiota in male Wistar rats fed either low- or high-fat diets for three weeks. Both pectin and guar gum reduced weight gain, adiposity, liver fat and blood glucose levels in rats fed a high-fat diet. Methoxylation degree of pectin (low, LM and high (HM)) and viscosity of guar gum (low, medium or high) resulted in different effects in the rats, where total blood and caecal amounts of SCFA were increased with guar gum (all viscosities) and with high methoxylated (HM) pectin. However, only guar gum with medium and high viscosity increased the levels of butyric acid in caecum and blood. Both pectin and guar gum reduced cholesterol, liver steatosis and blood glucose levels, but to varying extent depending on the degree of methoxylation and viscosity of the fibres. The medium viscosity guar gum was the most effective preparation for prevention of diet-induced hyperlipidaemia and liver steatosis. Caecal abundance of Akkermansia was increased with high-fat feeding and with HM pectin and guar gum of all viscosities tested. Moreover, guar gum had distinct bifidogenic effects independent of viscosity, increasing the caecal abundance of Bifidobacterium ten-fold. In conclusion, by tailoring the viscosity and possibly also the degree of methoxylation of dietary fibre, metabolic effects may be optimized, through a targeted modulation of the gut microbiota and its metabolites.

Formation of polysaccharide aerogels in ethanol

Abstract: Aerogels are outstanding materials, obtained by the sol–gel process. The production of polysaccharide aerogels is however time-consuming and their use for life-science applications is limited. To accelerate the production time, ethanol was used to induce the gelation of pectin, alginate, xanthan and guar gum. Polysaccharide aerogels were produced by dissolution in water, gelation in ethanol and supercritical drying. Only ethanol was used for the gelation without the use of any other cross-linking agent. In addition there was no solvent-exchange step prior to supercritical drying since the gelation occurred directly in ethanol. Differential scanning calorimetry was used to analyze the decompositions of the samples and also to measure their thermal conductivities. SEM and rheological analyses were performed in order to characterize the new materials. The prepared dry materials were highly porous and possessed some outstanding properties, namely, the low-methoxyl and high-methoxyl pectin monolithic aerogels possessed the highest surface areas yet reported, 510 m2 g−1 and 390 m2 g−1, respectively. To our knowledge this is the first known report regarding synthesis and characterization of pure xanthan and guar aerogels. Their surface areas were also high, 370 m2 g−1 and 110 m2 g−1, respectively. Very low thermal conductivity was observed for pectin aerogels, 0.021 W m−1 K−1.

Characterization of mannanase from Bacillus circulans NT 6.7 and its application in mannooligosaccharides preparation as prebiotic

Abstract: This study focused on the characterization of mannanase from Bacillus circulans NT 6.7 for mannooligosaccharides (MOS) production. The enzyme from B. circulans NT 6.7 was produced using defatted copra meal as a carbon source. The mannanase was purified by ultrafiltration and column chromatography of Q-Sepharose. The purified protein (M1) was a dimeric protein with a 40 kDa subunit. The purified M1 exhibited optimum pH and temperature at pH 6.0 and 60 °C, respectively. It was activated by Mn2+, Mg2+, and Cu2+, and as inhibited by EDTA (45–65 %). The purified enzyme exhibited high specificity to beta-mannan: konjac (glucomannan), locust bean gum (galactomannan), ivory nut (mannan), guar gum (galactomannan) and defatted copra meal (galactomannan). The defatted copra meal could be hydrolyzed by purified M1 into mannooligosaccharides which promoted beneficial bacteria, especially Lactobacillus group, and inhibited pathogenic bacteria; Shigella dysenteria DMST 1511, Staphylococcus aureus TISTR 029, and Salmonella enterica serovar Enteritidis DMST 17368. Therefore, the mannanase from B. circulans NT 6.7 would be a novel source of enzymes for the mannooligosaccharides production as prebiotics.

Formulation of mayonnaise with the addition of a bioemulsifier isolated from Candida utilis

Abstract: Biosurfactants have a number of industrial applications due their diverse properties, such as emulsification, foaming, wetting, and surface activity. The aim of the present study was to produce a biosurfactant from Candida utilis and employ it in the formulation of a mayonnaise. The biosurfactant was produced in a mineral medium supplemented with glucose and canola waste frying oil at 150 rpm for 88 h. The product was biologically tested on rats and in different formulations of mayonnaise, which were submitted to microbiological evaluations. The biosurfactant was added to the diet of the rats for 21 days. Greater consumption was found of the experimental diet. Moreover, no changes were found in the liver or kidneys of the animals, demonstrating the absence of a toxic effect from the biosurfactant. Six different formulations of mayonnaise were prepared and tested regarding stability with the addition of carboxymethyl cellulose and guar gum (combined and isolated) after 30 days of refrigeration. The most stable formulation with the best quality was obtained with combination of guar gum and the isolated biosurfactant, with an absence of pathogenic microorganisms. In conclusion, the potential and innocuousness of the biosurfactant isolated from C. utilis indicates its safe use in food emulsions.

Development and Characterization of Nanoembedded Microparticles for Pulmonary Delivery of Antitubercular Drugs against Experimental Tuberculosis.

Abstract: The foremost objective of the present research study was to develop and evaluate the potential of rifampicin (RIF) and isoniazid (INH) loaded spray dried nanoembedded microparticles against experimental tuberculosis (TB) In this study, RIF-INH loaded various formulations (chitosan, guar gum, mannan, and guar gum coated chitosan) were prepared by spray drying and characterized on the basis of in vitro as well as in vivo studies Results showed that guar gum spray dried particles showed uniform size distribution with smooth surface as compare to mannan formulations Guar gum batches exhibited excellent flow ability attributed to their optimum moisture content and uniform size distribution The drug release showed the biphasic pattern of release, ie, initial burst followed by a sustained release pattern The preferential uptake of guar gum coated formulations suggested the presence and selective uptake capability of mannose moiety to the specific cell surface of macrophages In vivo lung distribution study showed that guar gum coated chitosan (GCNP) batches demonstrated prolonged residence at the target site and thereby improve the therapeutic utility of drug with a significant reduction in systemic toxicity Optimized drug loaded GCNP formulation has resulted in almost 5-fold reduction of the number of bacilli as compared to control group Histopathology study also demonstrated that none of the treated groups show any evidence of lung tissue abnormality Hence, GCNPs could be a promising carrier for selective delivery of antitubercular drugs to alveolar macrophages with the interception of minimal side effects, for efficient management of TB

Depolymerization of guar gum solution using different approaches based on ultrasound and microwave irradiations

Abstract: The present work investigates the application of ultrasound and microwave operated individually or in combination for depolymerization of aqueous solution of guar gum. In addition, intensification aspects due to the use of an initiator, potassium persulfate (KPS), has been investigated. The extent of depolymerization has been analyzed in terms of the reduction in intrinsic viscosity. Also, the effectiveness of treatment approach has been analyzed on the basis of kinetic rate constant, limiting intrinsic viscosity and the time required for the desired extent of viscosity reduction. The kinetic rate constant has been found to increase with an increase in the temperature and KPS loading. For the individual operation involving irradiations, the rate was found to be higher in the case of ultrasound as compared to the microwave irradiations. In the case of sequential approach, microwave followed by ultrasound was more effective as compared to the approach of ultrasound followed by microwave. The obtained results clearly established that ultrasound in combination with KPS was the most effective approach for depolymerization. The work has also enabled to understand the effective role of KPS and operating temperature in intensifying the viscosity reduction of guar gum polysaccharides.

In vitro starch digestibility and in vivo glucose response of gelatinized potato starch in the presence of non-starch polysaccharides

Abstract: Blending non-starch polysaccharides with starch is expected to change the rate and extent of starch digestion and has a potential effect on glucose response. The objective of this study was to investigate the effects of four water-soluble non-starch polysaccharides: xanthan gum, guar gum, pectin, and konjac-glucomannan, on in vitro starch digestibility and in vivo glucose response of gelatinized potato starch. Gelatinized potato starch was digested rapidly, and the added polysaccharides significantly reduced the digestion of gelatinized potato starch even over a short reaction time. Postprandial blood glucose response in rats was reduced by the addition of polysaccharides to gelatinized potato starch. The effects on the blood glucose level after ingestion were dependent on the type of polysaccharide. The addition of xanthan gum significantly reduced the blood glucose levels at 30 min, whereas guar gum and pectin reduced the levels at 60 min. The interaction between gelatinized potato amylopectin and polysaccharides was investigated using a quartz crystal microbalance. Xanthan gum was found to be immobilized on the layer of gelatinized amylopectin, suggesting that interaction between starch and xanthan gum is one of the major factors in starch hydrolysis inhibition.

Characterization and evaluation of curcumin loaded guar gum/polyhydroxyalkanoates blend films for wound healing applications

Abstract: The present paper explores the ‘in situ’ fabrication of guar gum/polyhydroxyalkanoates-curcumin blend (GPCC) films in view of their increasing applications as wound dressings and antibacterial materials. Curcumin is incorporated to assess its bactericidal activity and to enhance the production and accumulation of the extracellular matrix in the healing process. In order to characterize the nature of the polymer network in the blend, FTIR/ATR spectra analysis and TGA are performed. The results reveal that the rigidity of the guar gum/PHBV blend improves with the increase of PHBV content due to the formation of non-covalent interactions, especially H-bonds, between these molecules. Electron microscopy analyses reveal the homogenecity of the blends and surface roughness of the blended films, favoring cell attachment and cell proliferation compared with the film without curcumin. The anti-microbial study demonstrate that the bactericidal activity is more effective against Gram-positive strains than Gram-negative strains. Results of the in vivo wound healing study in an animal model demonstrates that the developed curcumin loaded guar gum/PHBV blend film shows markedly enhanced wound healing compared to the control one.

Effect of Gum Type and Flaxseed Concentration on Quality of Gluten-Free Breads Made from Frozen Dough Baked in Infrared-Microwave Combination Oven

Abstract: As prevalence of celiac disease increases, the demand for gluten-free products also increases. Researchers are still trying to improve gluten-free bread quality and shelf life to reach the quality of wheat bread. In this study, the aim was to obtain gluten-free breads made from frozen dough with acceptable specific volume, crumb firmness, and color and to investigate the effects of gum type and flaxseed concentration on the quality of gluten-free breads. Three different gum types (guar gum, xanthan gum, locust bean gum) were used. Gums were added to the formulation at 1 % level. Flaxseed was also added to the formulation at different concentrations (0, 2.5, and 5 %). After frozen storage at −20 °C for 10 days, frozen samples were thawed at +4 °C. Thawed samples were then fermented and baked in infrared-microwave (IR-MW) combination oven. The quality parameters (weight loss, specific volume, hardness, and color) of gluten-free breads were determined. In addition to the measurement of hardness of fresh samples, hardness of staled samples during the 72-h storage was also determined to investigate the effects of different formulations in retarding the staling of gluten-free breads. When the effects of gums and flaxseed concentration on the quality of breads were considered, the quality of gluten-free breads formulated with guar gum-5 % flaxseed was found to be better (with lower hardness, higher specific volume, and better color) than the other samples. The results obtained during the 72-h storage also demonstrated that gluten-free breads formulated with guar gum-5 % flaxseed had the lowest hardness values.