Showing papers on "Guar gum published in 2012"

Effect of different fibers on batter and gluten-free layer cake properties

Abstract: The effect of different fibers, added individually or in combination, to improve the functional properties of gluten-free layer cakes was examined. Soluble (inulin and guar gum), and insoluble (oat fiber) fibers were used to replace up to 20% of rice flour in gluten-free layer cakes formulation. The incorporation of fibers increased the batter viscosity, with the exception of inulin. Fiber enriched gluten-free cakes containing blends of oat fiber–inulin resulted in improved specific volume. Significantly brighter crust and crumb was obtained in the presence of fibers, excepting the crumb of oat–guar gum containing cake. Fibers and its blends increased the crumb hardness; but the smallest effect was observed with the addition of oat, individually or combined with inulin. Enriched cakes increased significantly their dietary fiber content, which was connected to the nature of the fibers added. Fibers significantly affected the in vitro hydrolysis of starch fractions, being the most pronounced effect the decrease in the slowly digestible starch. Overall combination of oat fiber–inulin resulted in better gluten-free cakes.

Viscoelastic gels of guar and xanthan gum mixtures provide long-term stabilization of iron micro- and nanoparticles

Abstract: Iron micro- and nanoparticles used for groundwater remediation and medical applications are prone to fast aggregation and sedimentation. Diluted single biopolymer water solutions of guar gum (GG) or xanthan gum (XG) can stabilize these particles for few hours providing steric repulsion and by increasing the viscosity of the suspension. The goal of the study is to demonstrate that amending GG solutions with small amounts of XG (XG/GG weight ratio 1:19; 3 g/L of total biopolymer concentration) can significantly improve the capability of the biopolymer to stabilize highly concentrated iron micro- and nanoparticle suspensions. The synergistic effect between GG and XG generates a viscoelastic gel that can maintain 20 g/L iron particles suspended for over 24 h. This is attributed to (i) an increase in the static viscosity, (ii) a combined polymer structure the yield stress of which contrasts the downward stress exerted by the iron particles, and (iii) the adsorption of the polymers to the iron surface having an anchoring effect on the particles. The XG/GG viscoelastic gel is characterized by a marked shear thinning behavior. This property, coupled with the low biopolymer concentration, determines small viscosity values at high shear rates, facilitating the injection in porous media. Furthermore, the thermosensitivity of the soft elastic polymeric network promotes higher stability and longer storage times at low temperatures and rapid decrease of viscosity at higher temperatures. This feature can be exploited in order to improve the flowability and the delivery of the suspensions to the target as well as to effectively tune and control the release of the iron particles.

Ocular drug delivery system: a reference to natural polymers

Abstract: Introduction: Ocular drug delivery is a very challenging endeavor due to the unique anatomical and physiological barriers. The low ocular bioavailability (<10%) obtained from conventional formulations has forced the scientists to develop new formulations to deliver drugs to ocular tissues at a controlled rate to reduce frequent instillations. The natural polymers have represented the potential to deliver drugs topically through the limited precorneal area and release over a prolonged time period. Areas covered: The important points to be considered during the fabrication of ophthalmic formulations for example, properties of drug molecule and polymer which affect the release rate are discussed. Novel polymers, like arabinogalactan, xyloglucan, gum cordia, locust bean gum, carrageenan and Bletilla striata polysaccharide, besides the conventional polymers like chitosan, starch, sodium alginate, sodium hyaluronate, xanthan gum, gelatin, gellan gum, guar gum, collagen and albumin, have demonstrated the potenti...

Effect of hydrocolloid (guar gum) incorporation on the quality characteristics of bread.

Abstract: Effect of guar gum on the rheological properties of dough, physico-chemical properties of bread, sensory characteristics of finished product and white bread quality was studied. At all levels of incorporation, there were increases water absorption from 61.2 to 64.5%, lowered the dough development time from 6.20 to 5.60 min, increased gluten development, increased dough stability, increased break down time from 37.3 to 40.5 min, higher the mixing tolerance index from 52.2 to 54.6 BTU and increased the elasticity i.e. 72.3 to 74.6 BU of the dough. The external characteristics like color of crust, symmetry, evenness, character of crust and aroma was improved linearly with increased the concentration of guar gum and also internal characteristics like color of crumb, taste and texture was improved.

Antihyperglycemic and antihyperlipidemic effects of guar gum on streptozotocin-induced diabetes in male rats.

Abstract: Background: Herbal medicine is widely used in the treatment of diseases like diabetes mellitus. We investigated the effects of guar gum in diabetic rats for the reduction of the risk of diabetes and cardiovascular disease. Dietary pattern emphasizing foods high in complex carbohydrates and fiber are associated with low blood glucose and cholesterol levels. Materials and Methods: Diet containing 0%, 5%, 10% and 20% (w/w) guar gum was fed to diabetic rats for 28 days. Blood serum glucose, triglycerides, cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol levels, atherogenic index levels, body weights and food intake were monitored at 0, 7.14 and 28 days after induction of diabetes. Results: In spite of the fact that diabetes elevated blood lipids in all rats after 14 days, the guar gum diet significantly decreased the serum concentration of cholesterol, triacylglicerols and LDL-C and atherogenic index. The most significant result in this study was the reduction of blood glucose in diabetic rats treated with the guar gum diet after 28 days versus non- and glibenclamide-treated rats. The gum promoted a general improvement in the condition of the diabetic rats in body weight and food intake in comparison with nontreated rats. Conclusion: The results of this research suggest that guar gum was significantly effective in comparison with glibenclamide in the treatment of hyperlipidemia and hyperglycemia in diabetes rats. Therefore, it may be suggested as a reliable fiber in diabetic regimes in diabetic patients.

Novel Multinutrient Fertilizer and Its Effect on Slow Release, Water Holding, and Soil Amending

Abstract: This study was carried out to develop a novel slow-release fertilizer, which is based on natural attapulgite (APT) clay as a matrix, guar gum (GG) as an inner coating, and guar gum-g-poly(itaconic acid-co-acrylamide)/humic acid (GG-g-P(IA-co-AM)/HA) superabsorbent polymer as an outer coating. The coated compound fertilizer granules with diameter in the range of 2–3 mm possess low moisture content and high mechanical hardness. The effects of APT matrix, GG, and superabsorbent polymer coatings on nutrients release were explored. The influence of the product on water-holding capacity of soil was determined. The degradation behavior of the GG-g-P(IA-co-AM)/HA outer coating was assessed by examining the weight loss with incubation time in soil. The experimental data and analysis in this study indicated that the product prepared by a simple route can effectively reduce nutrient loss in runoff or leaching, improve soil moisture content, and regulate soil acidity and alkalinity level.

Effect of Crosslinking on swelling behaviour of IPN hydrogels of Guar Gum and Polyacrylamide

Abstract: An IPN system comprising of guar gum and polyacrylamide has been made in aqueous medium. Polymerization of acrylamide has been achieved in the presence of guar gum using potassium persulphate as initiator. One set of gels has been made with N,N’-methylene-bis-acrylamide (MBA) as the crosslinking agent and another with MBA and Gluteraldehyde(GA) as crosslinking agents. The effect of using single and two crosslinking agents on the gel structure has been evaluated by studying the swelling behaviour of gels made with different amounts of crosslinking agents. The gels crosslinked with MBA alone exhibited 3-5 times higher swelling when compared to the gels with 2 crosslinkers. The kinetics of swelling has been studied and the swelling parameters have been evaluated

Development and In-vitro Evaluation of a Contraceptive Vagino-Adhesive Propranolol Hydrochloride Gel.

Abstract: The objective of the present investigation was to develop and evaluate a contraceptive vagino-adhesive propranolol hydrochloride gel. To achieve this, various mucoadhesive polymers including guar gum (1-4% w/w), sodium alginate (4-7% w/w), xanthan gum (2-5% w/w ), HPMC 4000 (3-5% w/w), Na CMC (4-7% w/w), carbomer 934 and carbomer 940 both in the range of 0.5-2.0% w/w, were dispersed in an aqueous-based solution containing the drug (1.6% w/w). The mucoadhesive properties of the gels were assessed on sheep vaginal mucosa (as model mucosa) in pH 4.5 citrate-phosphate buffer at 37°C. Formulations containing charged functional groups in their polymeric structure, showed higher mucoadhesive strengths in comparison to those composed of neutral polymers. In-vitro drug release profiles of the gels were determined in pH 4.5 citrate-phosphate buffer. Results indicated that, only formulation F13 (containing sodium alginate 6.5% w/w), could release its drug over 12 h, with a burst release at the initial phase followed by a sustained release pattern. This formulation, which showed a good mucoadhesive strength (386.97 ± 9.31 mN), was considered as the final formulation and underwent complementary tests including determination of drug content and duration of mucoadhesion. Its drug content was found to be 101.05 ± 0.106% (n = 3) and it attached to the model mucosa for more than 10 h. In conclusion, formulation F13 was considered as the most desirable formulation as it exhibited appropriate mucoadhesive properties while having the potential of providing an immediate contraceptive effect, followed by a prolonged drug release which is assumed to render longer contraceptive efficacy.