Showing papers on "Guar gum published in 1988"

Do viscous polysaccharides slow absorption by inhibiting diffusion or convection

Abstract: Viscous polysaccharides such as guar gum delay absorption probably by impairing the access of luminal contents to the absorptive epithelium. Measurements of the electrical resistivity of saline solutions were carried out to determine if guar gum (0.5, 0.75 and 1 per cent w/v), in concentrations which impaired absorption in vitro, delayed diffusion of solutes or inhibited convection of luminal contents. Our results indicated that guar had no effect on the mobility of ions in a completely unstirred solution but delayed the time taken for saline solutions of different resistivity to achieve complete mixing, when they were brought into contact inside a vessel, which was rotated at a constant speed. The time taken to achieve complete mixing was directly related to the viscosity of the guar solutions. The effect of intestinal contraction on the absorption of glucose was simulated in an in vitro model, consisting of a length of dialysis tubing, alternately contracted at each end. Movement of glucose out of the dialysis tubing was increased by increasing the rate of contraction. The incorporation of guar gum into the solution prevented the rise in glucose uptake produced by increasing the rate of contraction. These effects suggest that guar probably reduces absorption by resisting the convective effects of intestinal contractions.

Moisture Sorption Characteristics of Several Food Fibers

Abstract: Adsorption behavior of microcrystalline cellulose, guar gum, wheat bran and oat bran were compared at 4, 25, and 37°C. Guar gum adsorbed the most water and microcrystalline cellulose adsorbed the least. Adsorption abilities of oat bran and wheat bran were similar at low and intermediate water activity levels. However, wheat bran was able to adsorb more moisture in the high water activity regions of the isotherm. Of the four fibers studied, particle size reduction had the greatest effect on sorption properties of wheat bran, in part, due to the reduction of surface area available for binding at the monolayer.

The relation between bacterial degradation of viscous polysaccharides and stool output in human beings.

Abstract: 1. The relation between bacterial degradation of three viscous polysaccharides (guar gum, ispaghula and xanthan gum) by colonic bacteria in vitro and their effects on colonic function were investigated by comparing the results of anaerobic in vitro incubations with fresh faeces from seven healthy volunteers (measuring viscosity, pH and gas production) with the effects of feeding all three polysaccharides to the same volunteers for 1 week each (14-15 g/d) on faecal mass and whole-gut transit time. 2. Guar gum was rapidly fermented in vitro by faecal bacteria from all volunteers with concomitant loss of viscosity, reduction in pH and generation of gases. Ispaghula maintained its viscosity during incubation, but the pH fell significantly. The results of xanthan gum incubations showed considerable individual variation. 3. Only ispaghula significantly increased faecal mass, whilst none of the gums significantly affected stool frequency or transit time. Statistical analysis of the pooled results showed that although transit time and faecal output were inversely related, feeding viscous polysaccharides could influence these indices independently. Stool frequency was significantly correlated with the transit time, but not the faecal output. 4. Transit time was reduced by gum feeding to a significantly greater extent in those subjects whose faecal bacteria reduced or removed the viscosity of that gum, than in those subjects where the viscosity was maintained. In contrast, there was a smaller increase in faecal mass when the viscosity of the appropriate cultures was removed than when it was maintained or reduced. Increases in stool frequency were significantly associated with hydrogen production from in vitro cultures.

Effects of solid and liquid guar gum on plasma cholesterol and triglyceride concentrations in moderate hypercholesterolemia.

Abstract: Guar gum is a dietary fiber reported to decrease plasma cholesterol concentration. This study investigated the effect of guar therapy in 50 men with moderately elevated plasma cholesterol who were randomized to an 8-week study of guar therapy. Three forms of guar gum were used: a medium viscosity solid or liquid form, a high viscosity liquid form or placebo. When the medium viscosity guar therapy groups were combined, 4 weeks of therapy were shown to result in a substantial reduction in total and low density lipoprotein (LDL) cholesterol of 25 mg/dl and 23 mg/dl (p = 0.035 and 0.12), respectively. The high viscosity guar group had a reduction in total cholesterol and LDL cholesterol of 37 and 30 mg/dl, respectively (p <0.003 and p <0.02). Following 8 weeks of therapy, a return toward baseline values was observed. No significant changes were demonstrated in blood chemistries, triglyceride values, total high density lipoprotein (HDL) cholesterol or the HDL2 fraction of HDL cholesterol. The effect of the solid and liquid forms of guar on plasma cholesterol reduction was similar. This study shows that a nonpharmacologic dietary additive reduces plasma total and LDL cholesterol.

High temperature guar-based fracturing fluid

Abstract: A fracturing fluid based on quar gum exhibiting good viscosity and stability at temperatures from about 80° C. to at least about 120° C. The fracturing fluid includes a guar gum, a zirconium or hafnium cross-linking agent, and a bicarbonate salt in an aqueous solution at a pH from about 8 to about 10.

The effect of guar gum on the distribution of a radiolabelled meal in the gastrointestinal tract of the rat.

Abstract: 1. The effect of addition of guar gum (5 and 10 g/l) to a radiolabelled, homogenized, baked-bean test meal on the distribution of that meal in the gastrointestinal tract was investigated in groups of male rats killed at 25, 50, 100, 200, 300 and 400 min after gavage. 2. Addition of 5 and 10 g guar gum/l significantly increased the proportion of the meal remaining in the stomach at 25 and 50 min after gavage (P less than 0.01). 3. The heads of the control meal and meals containing guar gum reached the distal intestine within 25 min after gavage but radioactivity was not observed in the caecum until 100 min after administration of each of the meals. Addition of guar gum (5 and 10 g/l) delayed caecal filling even though the head of each meal reached the caecum at the same time after gavage. 4. The geometric centres of guar-gum-containing meals were proximal to that of the control meal at all times after gavage. 5. The observed delay in the passage of a guar-gum-containing meal through the stomach and small intestine is probably due to the viscous nature of the meal resisting the propulsive and mixing effects of the gastrointestinal contractions, thereby reducing access of the glucose to the absorptive epithelium. This could contribute to the observed reductions in postprandial glycaemia seen in previous studies after incorporating guar gum into a meal.

Comparison of galactomannan crosslinking with organotitanates and borates

Abstract: Water-soluble polymers crosslinked with metal ions form stable gels that are used in oil and gas production processes. We present an investigation of the chemistry of the binding between guar galactomannans and both borates and titanates using NMR and dynamic light scattering. The two monosaccharides comprising guar — methyl-β-D-galactopyranoside and methyl-α-D-mannopyranoside — have been studied as model compounds. High resolution13C NMR detected complexation of the sugars with borate but displayed no sign of complexation with either of the two titanates even at high titanate concentrations. Dynamic light scattering studies demonstrated the existence of colloidal titanium dioxide particles for both titanate crosslinkers. The loss of free titanium to the colloidal particles reduces the concentration of titanium crosslinking sites to below the detectable limits of NMR. The role of colloidal titanium dioxide colloids in these crosslinking reactions has not been reported previously. Data are presented following the growth of these particles with time as a function of pH and salt concentration. The observed particle growth kinetics explains the observed sensitivity of the guar gelation process to these variables.

Soft-serve frozen yogurt mixes

Abstract: A smooth textured soft frozen non-fat yogurt having a solids content between about 18 to 43% w. and an overrun of between about 35 to 65% is prepared by dissolving in cold water and freezing, in a soft serve freezer, a dry particulate composition comprising (a) about 0.5 to 2.0% w. of a stabilizing mixture consisting of 40-60% w. carrageenan, 20-40% w. of second stabilizer selected from the group consisting of xanthan gum, guar gum, locust bean gum, sodium alginate, gelatin, gum tragacanth, India gum, agar-agar and pectin and mixtures thereof and 20-30% W. CMC; (b) 3-14% w. of a dried yogurt powder, (c) 1.5-40% w. of added milk solids selected from the group consisting of non-fat dry milk solids, whey solids and whey protein concentrate; (d) 43-94% w. of a sweetening agent; (e) 0.03 to 10% w. of a flavoring agent; (f) 0.0 to 1.5% w. of an acidifying agent; and (g) 0.0 to 0.5% w. of the sodium salt of an acidifying agent. Xanthan gum, guar gum and locust bean gum and mixtures thereof are preferable as the second stabilizers. Sucrose, fructose and corn syrup solids admixed with maltodextrins are the preferred sweetening agents. The composition may vary according to neutral (e.g. vanilla, coconut, banana, etc.), chocolate (chocolate mint, chocolate mocha, etc.), and acidic fruit (e.g. peach, apricot, strawberry, lemon, etc.) flavor formulations.

Does adding fibre to a low energy, high carbohydrate, low fat diet confer any benefit to the management of newly diagnosed overweight type II diabetics?

Abstract: The effect of supplementing a low energy (roughly 5.0 MJ), high carbohydrate (180 g), low fat (roughly 25 g) diet with 10-15 g of either cereal fibre or guar gum was investigated in 24 newly diagnosed overweight non-insulin-dependent (type II) diabetics. The patients were divided into three treatment groups: one received a low fibre control diet throughout the study period of 20 weeks and the other received two supplements of cereal fibre and guar gum in a crossover manner. The nutrient content of the diets was kept constant throughout. Though patients taking the low fibre diet showed a smaller reduction in fasting plasma glucose concentrations over the first eight weeks than patients taking a high fibre diet, this difference was not evident at the end of 20 weeks; reductions in weight and glycated haemoglobin values were similar for each dietary regimen throughout the trial. There was little evidence that supplementing a low energy, high carbohydrate diet with fibre confers any therapeutic benefit to type II diabetics and no evidence that taking fibre as viscous polysaccharides is any more beneficial to overweight diabetics than taking a similar fibre supplement as cereal. On the contrary, guar gum caused more abdominal discomfort and flatulence than the other diets.

Occupational allergic rhinitis from guar gum

Abstract: Three cases of allergic rhinitis from a vegetable gum, guar gum, have been detected. Two subjects were exposed to fine guar gum powder (Emco Gum 563, Meyhall Chemical AG, Switzerland), an insulator in rubber cables, when opening cables in a power cable laboratory. After 1-2 years' exposure the patients developed rhinitis. Scratch-chamber tests, nasal provocation tests, nasal eosinophilia and a RAST test proved their allergy. A third subject developed allergic rhinitis from another guar gum product (Meyproid 5306, Meyhall Chemical AG) after 2 years' exposure in a paper factory. A positive skin test and nasal provocation test confirmed the diagnosis. A fourth case of possible allergy to guar gum after exposure to Meyproid 5306 in a paper factory is also presented. No final diagnosis was reached in this case (in 1974). The present subjects, only one of whom was atopic, developed allergy within 2 years, although their exposure to guar gum was not especially heavy. Therefore, when handling guar, adequate ventilation facilities should be provided and protective clothing, including a respiratory mask, should be worn.

Plasma enteroglucagon and small bowel cytokinetics in rats

Abstract: The influence ofdietary fiber on plasma glucagon and enteroglucagon (EG) and on ileal crypt cell production rate(CCPR)was assessed in the rat. A fiber-free semisynthetic diet and diets containing insoluble cellulose, Na-carboxymethylcellulose (CMC), guar gum, pectin, gum arabic, methylcelbubose (MC), and hydroxypropylmethylcellubose (HPMC) at 10 g/lOO g were fed for 14 d. Animals given soluble polysaccharides had plasma EG levels signifi- cantly higher than animals given insoluble cellulose, but only those fed the most viscous gums showed evidence of increased mucosal cell proliferation in the distal ileum. It was concluded that viscous nonfermentable polysaccharide gums stimulate the release of EG in the rat by slowing the absorption of nutrient, whereas the nonviscous polysaccharide gum arabic, or its breakdown products, probably directly stimulate mucosal endocrine cells. The failure of gum arabic to stimulate CCPR despite increased plasma EG indicated that EG alone is not a suffi- cient stimulus for increased mucosal cell proliferation. Am J C/in Nutr l988;47:l004-9.

Partially esterified polysaccharide (pep) fat substitutes

Abstract: Partially esterified oligosaccharides and polysaccharides (PEPs) of the formula [P--O--R) x ] n , where P is a polysaccharide having n=3-50 (preferably 3-10) C 4 -C 8 saccharide units, y is 0-4 (preferably 1 or 2), R is H or a C 3 -C 28 acyl group, and x is the degree of esterification ranging from 1-80 percent. The PEPs are used as indigestible fat substitutes (fat mimetics). They have non-caloric food values, with good organoleptic characteristics, are substantially resistant to intestinal absorption and do not appreciably hydrolyze in the digestive tract. Suitable polysaccharides are preferably selected from xanthan gum, guar gum, gum arabic, aliginates, cellulose hydrolysis products, hydroxypropyl cellulose, starch hydrolysis products, casein, Karaya gum and pectin. C 5 and C 6 oligosaccharides of n=3-10 units are preferred. The polysaccharides are transesterified with fatty acid methyl esters to create PEPs of a degree of esterification determined for each polysaccharide. The physical properties of the resultant PEPs range from a liquid oil, through fats, greases, and ultimately to waxes, and are useful in food formulations and for cooking as they have good mouth feel and characteristics similar to vegetable oils and fats. Being relatively non-absorbable, indigestible, and non-toxic they may be substitued for natural or processed oils and fats, while maintaining low caloric value.

Grafting of acrylamide onto guar gum using KMNO4/oxalic acid redox system

Abstract: The grafting of acrylamide onto guar gum in aqueous medium initiated by KMnO4/oxalic acid redox system has been studied gravimetrically at the temperature 35 ± 0.2°C. The effect of redox components, acrylamide concentration and quantity of guar gum has been studied in terms of percentage and efficiency of grafting. A plausible mechanism of grafting and a suitable rate expression has been suggested. The rate of grafting was found to increase with increase in temperature and concentrations of redox components and acrylamide, but, at high concentration of guar gum, the rate was found to decrease.

Hyposensitization agent of cedar pollen antigen

Abstract: A novel hyposensitization agent was prepared by covalently attaching a saccharide, e.g. homo- and heteroglycans, for example, starch, amylose, dextran, polysucrose, pullulan, elsinan, curdlan, gum arabic, gum tragacanth, guar gum, xanthan gum carrageenan, pectin, cellulose, glucomannan, chitosan, and lipopolysaccharide, and their derivatives and partial hydrolysates to, a cedar pollen allergen. The hyposensitization agent can be administered to a cedar pollinosis patient without fear of eliciting anaphylaxis and allergy within a shortened hyposensitization period because the hyposensitization agent much more enhances the production of immunoglobulin G and M antibodies which are specific to intact cedar pollen allergen, but extremely reduces the production of immunoglobulin E antibody which is specific to the allergen and responsible for anaphylaxis and allergy.

Treatment of chronic constipation with lactitol sweetened yoghurt supplemented with guar gum and wheat bran in elderly hospital in-patients.

Abstract: The faecal output of 33 elderly hospitalized patients was followed daily for 4 weeks. After an observation period of 1 week 18 patients received during the following 2 weeks a 150 ml portion of yoghurt containing lactitol, guar gum and wheat bran (fibre yoghurt group) twice daily. Fifteen control patients received the same volume of yoghurt without lactitol, guar gum or wheat bran (control yoghurt group). The study design was randomized double-blind. The mean faecal output increased 1.6-fold in patients receiving fibre yoghurt, while the corresponding value for control patients was 1.2 (p less than 0.05). About 50% of the fibre yoghurt group and 25% of the controls considered the treatment effective. Some in the fibre yoghurt group experienced meteorism and loose stools. No significant changes were observed in blood glucose, serum cholesterol or triglyceride values, body weights or faecal pH values in either group.

Long-term effects of guar gum and microcrystalline cellulose on glycaemic control and serum lipids in type 2 diabetes.

Abstract: The effects of guar gum (GG) and microcrystalline cellulose (MC) on metabolic control and serum lipids were compared in a double-blind, cross-over trial in 18 poorly controlled Type 2 diabetic patients. There were two 12 week treatment periods separated by a 4 week wash-out period. A significant reduction in fasting BG was found after 6 weeks treatment with GG, but the initial level was regained after further 6 weeks, at the end of the treatment period. No statistically significant change in fasting BG was observed with MC. Serum cholesterol was lowered by 10% during GG treatment. Microcrystalline cellulose had no effect on serum lipids. The results suggest, that during 12 weeks supplementation with guar gum, the improvement in glycemic control was not sustained, but that it might reduce the risk of macrovascular disease in diabetic patients.

Concentration effect of soluble dietary fibers on postprandial glucose and insulin in the rat.

Abstract: The effects of different soluble fibers on blood glucose and insulin responses to voluntary meals in the rat were investigated. Rats (165-180 g) were adapted for 2 weeks to a fiber-free control diet or fiber diets made by dilution of the fiber-free diet with the fiber. Fibers and concentrations used were carboxymethylcellulose (1.25, 2.5, and 5%), guar gum, oat beta-glucan (2.5, 5, and 7.5%), and mustard mucilage (5, 10, and 15%) as the soluble fibers, and cellulose (20%) as the insoluble fiber. Meal challenges (0.75 g/100 g body weight offered for consumption within a period of 15 min) were made with the adaptation diet. Soluble fibers reduced food intake and growth with a concentration effect, while cellulose increased food intake. All fibers reduced dry matter and nitrogen digestibilities but had no effect on the protein efficiency ratio. Only carboxymethylcellulose (at 5%) reduced postprandial glycemia at 30 min (p less than 0.05). Cellulose had no effect on plasma insulin which was markedly reduced with a concentration effect by all soluble fibers (except mustard mucilage) in the following decreasing order: carboxymethylcellulose, guar gum, beta-glucan, and mustard mucilage. The effect of fibers seemed closely related to the viscosity of fiber solutions in the presence of the diet ingredients. The present findings demonstrate the positive effect of fibers on postprandial insulinemia but with only a slight effect on glycemia. They indicate that the physicochemical interaction of the fibers with other dietary ingredients is important.

Evaluation of guar biscuits for use in the management of diabetes: tests of physiological effects and palatability in non-diabetic volunteers.

Abstract: A guar-shortbread biscuit has been successfully developed and tested for possible use in the dietary management of diabetes. A dose-response study was undertaken to estimate the amount of guar gum needed in the biscuit recipe to reduce postprandial glycaemia and insulinaemia. A control biscuit and three types of guar biscuit corresponding to a low, medium and high dose of guar (2.9, 6.0 and 9.1 g of guar respectively) were given to 8 non-diabetic subjects, and blood glucose and plasma insulin levels were determined at fasting, and at the postprandial times 30, 60, 90 and 120 min. Integrated insulin increments were estimated by calculation of the area under the curve. Sensory analysis of the biscuits was carried out by 36 non-diabetic panellists using a standard smiley chart containing hedonic phrases. No significant differences in the blood glucose increments were found between the control biscuit and the guar biscuits. However, all three guar biscuits produced smaller insulin rises than the control at all the postprandial times; statistically significant falls were indicated at the 60-min peak and 120-min times and for the integrated values. A linear regression model describing the relationship between integrated insulin and the dose of guar ingested is proposed. We have estimated from this model that a reduction of 209 mU/min/l in the integrated insulin can be achieved for every 1 g of guar incorporated into the biscuit. Mean hedonic scores indicated that all the guar biscuits were palatable, particularly the low-dose variety which was given a score almost identical to that of the control. A significant insulin-sparing effect in non-diabetic subjects was achieved using a palatable guar biscuit containing less than 3 g of guar flour.

Cholesterol-lowering combination compositions of guar gum and niacin

Abstract: An antihyperlipidemic pharmaceutical or dietary supplement composition for oral use consisting essentially of a combination of niacin and guar gum, and a method of lowering cholesterol levels with such oral pharmaceutical composition, or by the simultaneous oral administration of the active ingredients thereof, which eliminates the usual undesirable flushing and itching side effects of niacin while effectively lowering cholesterol levels, especially LDL cholesterol levels, is disclosed.

Dietary fiber supplements: effects on serum and liver lipids and on liver phospholipid composition in rats.

Abstract: Rats (6 per group) were fed semipurified diets containing either particulate fibers (alfalfa, 10%; cellulose, 10%; bran, 10%), a soluble ionic fiber (pectin 5%), soluble, nonionic fibers (guar gum, 5%; Metamucil, 10%), a mixed fiber preparation (Fibyrax, 10%, or an insoluble, ionic bile acid-binding resin (cholestyramine, 2%). The control group was fed the unsupplemented diet. The feeding period, during which diet and water were provided ad libitum, was 28 days. Compared with the control group, serum total cholesterol levels were increased by more than 10% in rats fed alfalfa and decreased by more than 10% in rats fed cellulose, guar gum, Fibyrax and cholestyramine. There were no significant differences in percentage of plasma HDL cholesterol. Serum triglycerides were elevated in the groups fed alfalfa, pectin, guar gum or Fibyrax and reduced in the group fed Metamucil. Plasma phospholipids were elevated in rats fed alfalfa or bran, unaffected in rats fed pectin or Metamucil and reduced in the other groups. Liver total cholesterol was elevated in all groups but those fed wheat bran and cholestyramine. The percentage of liver cholesterol present as ester was elevated in every group except that fed cholestyramine. Liver triglycerides were reduced in rats fed guar gum or Metamucil and elevated in those fed alfalfa. Liver phospholipids were lowered in the group fed cellulose. Liver phospholipids were fractionated by thin layer chromatography to give phosphatidylcholine (PC), phosphatidylethanolamine (PE), sphingomyelin (Sph), lysophosphatidylcholine (LPC) and phosphatidylinositol plus phosphatidylserine (PI + PS).(ABSTRACT TRUNCATED AT 250 WORDS)

Studies on a Soy‐Based Low‐Fat Spread

Abstract: A soy protein-lipid concentrate derived from the suspension obtained by grinding soaked and blanched soybeans in water was used, with suitable vegetable fats, as a base for the preparation of a low-calorie spread. Skimmilk powder improved mouth-feel and flavor. Sodium citrate increased flowabiliry of the hot spread and decreased oiling off of the finished product. Hydroocolloids such as carrageenan and guar gum could effectively enhance spreadability. Plasticizers, viz., sorbitol and glycerol, favorably influenced viscosity, and texture and flavor characteristics. Butter annatto and β-carotene used as colorants, with certain commercial flavorings, rendered the product sensorily close to traditional butter. The spread had distinctly superior spread-ability properties. It kept well for about 3 months at refrigeration temperature.

Enzymatic preparation of β-1,4-mannooligosaccharides and β-1,4-glucomannooligosaccharides

Abstract: Publisher Summary Mannooligosaccharides have been prepared from partial acid and enzymatic hydrolysates of plant mannans such as ivory nut, guaran, coffee bean, white spruce, and lucerne seeds. This ordinary preparation method, however, does not yield a substantial quantity of oligosaccharides. The chapter describes preparation method for mannooligosaccharides from copra mannan using the mannanase system from Streptomyces sp. The mannanase of Streptomyces has been observed to rapidly decrease the viscosity of viscous polysaccharides such as konjac glucomannan, guar gum, and locust bean galactoglucomannans. The enzyme is a typical endoenzyme. Therefore, the products arising from the enzymatic degradation of the substrate are heterooligosaccharides, that is, various glucomanno- or galactomannooligosaccharides. The chapter also describes the preparation of glucomannooligosaccharides from konjac glucomannan.

Grafting of methyl methacrylate onto guar gum by hydrogen peroxide initiation

Abstract: Graft copolymerization of methyl methacrylate (MMA) onto guar gum (GG) in aqueous slurry has been carried out using hydrogen peroxide (H2O2) as initiator. The copolymers were characterized by infrared spectroscopy. The grafting parameters like percent grafting, grafting efficiency, percent add-on, and the grafting frequency were determined, and the effect of reaction time, concentration of initiator, and [GG]/[MMA] ratios on the grafting parameters have been discussed. The decrease in % add-on at increasing concentration of H2O2 indicated enhancement in the rate of homopolymerization of methyl methacrylate.

Partially decomposed product of hardly digestible polysaccharides, its production and food containing same

Abstract: PURPOSE:To produce a partially decomposed product of hardly digestible polysaccharides useful as a dietary fiber, etc, by treating hardly digestible polysaccharides originated from vegetables with a plant-tissue disintegration enzyme, thereby decreasing the viscosity of the polysaccharides CONSTITUTION:Hardly digestible polysaccharides originated from vegetables such as guar gum, tamarind gum or konjak mannan are partially decomposed with a plant tissue disintegration enzyme having galactomannase activity, cellulase activity, etc, to obtain a partially decomposed product of hardly digestible polysaccharides having a viscosity of =50% (determined by South-gate method) The product is used as a dietary fiber or added to various dietary foods