• Microbiology and Biotechnology Letters
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• v.32 no.2
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• pp.117-122
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• 2004

Bacillus sp. $\beta$-mannanase was purified by DEAE-sephadex ion exchange column chromatography. The specific activity of the purified enzyme was 21.57 units/$m\ell$ protein, representing an 95.33-folds purification of the original crude extract. The final preparation thus obtained showed a single band on SDS-polyacrylamide gel electrophoresis. The molecular weight was determined to be 38.9 kDa. Guar gum galactomannan was hydrolyzed by the purified $\beta$-mannanase, and then the hydrolysates was separated by activated carbon column chromatography and Sephadex G-25 gel filtration. The main hydrolysates were composed of D.P. (Degree of Polymerization) 5 and 7 galactomannooligosaccharides. To investigate the effects of guar gum galactomannooligosaccharides on in vitro growth of Bifidobacterium longum, B. bifidum, B. infantis, B. adolescentis, B. animalis, and B. breve, Bifidobacterium spp. were cultivated individually on the modified-MRS medium containing carbon source such as D.P. 5 and D.P. 7 galactomannooligosaccharides, respectively B. longum and B. bifidum grew up l0-fold and 9.8-fold more effectively by the treatment of D.P. 5 galactomannooligosaccharides, compared to those of standard MRS medium. Especially, D.P. 5 was more effective than D.P. 7 galactomannooligosaccharide on the growth of Bifidobacterium spp.

• Applied Biological Chemistry
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• v.33 no.3
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• pp.216-222
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• 1990

For the improvement of the nutritive value of extruded noodles, dry soymilk residue flour (DSRF) was mixed with wheat How. The effects of the addition of DSRF on the viscosity of wheat flour and the quality of cooked noodles were evaluated As the proportion of DSRF addition was in-creased the viscosity of composite flour was decreased And so were the texture and cooking quality of noodles. To improve noodle-making characteristics of extruded noodles with 10% DRFF, Na-alginate, Na-carboxymethyl cellulose, guar gum crude gluten and xanthan gum were added. Then, the noodle-making characteristics were examined. The viscosity increased with the increase in the concentration of additives and Bnnthan gum was the most effective. The texture of noodles supplemented by Na-alginate 2.0%, Na-carboxymethyl cellulose 2.0%, guar gum 2.0%, xanthan gum 1.0% was similar to that of wheat flour noodles. The results of sensory test (color and texture) was coincidal with the results of instumental tests.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.20-25
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• 2008

Effects of commercial and lab-generated gellan gums on the textural properties, structure, and aging of wheat and maize starch gels were investigated using a rapid visco-analyzer (RVA), rheometer, scanning electron microscope (SEM), and X-ray diffractometer. Gellan and guar gums increased the peak and final viscosities, but xanthan gum and gum arabic reduced them. The maize starch had higher breakdown viscosity than the wheat starch, regardless of the type of gum. The hardness of all starch gels increased during storage, but their cohesiveness and springiness decreased. The degree of the gel hardness showed higher in maize starch than in wheat starch and the effect of gum addition had a difference with gum type. The wheat starch-guar and -gellan gum mixed gels showed higher elasticity and cohesiveness after storage. The starch-gellan gum mixed gels had dense and stable network structures, and were well maintained even after 7 days of storage. Most of the gums had anti-aging effect on X-ray diffraction pattern of starch gels.

• Applied Biological Chemistry
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• v.33 no.3
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• pp.209-215
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• 1990

For the improvement of the nutritive value of extruded noodles, soybean flour(SF) was mixed with wheat flour. The effects of the addition of SF on the viscosity of wheat flour and the quality of cooked noodles were evaluated. As the proportion of SF addition was increased, the viscosity of composite flour was decreased, And so were the texture and cooking quality of noodles. To improve noodle-making characteristics of extruded noodles with 10% SF, Na-alginate, Na-car-boxymethyl cellulose, guar gum, crude gluten and xanthan gum were added. Then, the noodlemaking characteristics were examined. The viscosity increased with the increase in the concentration of additives and xanthan gum was the most effective. The texture of noodles supplemented by Na-alginate 2.0%, Na-carboxymeihyl cellulose 2.0%, guar gum 2.0%, xanthan gum 1.0% was similar to that of wheat flour noodles. The results of sensory test(color and texture) was coincidal with the results of instrumental tests.

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.939-943
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• 1999

Recently there has been an explosion of interest in the topic of biodegradable polymers for medical applications. In this study, films were prepared by solution casting method using natural polymers (xanthan, locust bean, guar gum, chitosan and algin) as biomaterials. Biocompatibility of films prepared from natural polymer as a skin implant was evaluated. These biodegradable films were subcutaneously implanted in the back of rats and their biodegradability was investigated by the evaluation of changes in structure, film weight and hematology as a function of time for the biotransformation. The result of rats test showed that locust bean and guar gum induced some suspects of non-biocompatibility in the tissue by foreign body reaction 24 and 48 hrs after implantation. These results showed the potential of partial biodegradable films prepared from natural polymer for ideal skin biomaterials at short period.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.426-432
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• 2016

Purpose: The consumption of noodles has increased domestically. However, noodles with high carbohydrate content can cause an increase in blood glucose compared with other foods. Therefore, in this study, Naengmyeon with high resistant starch was prepared for decreasing blood glucose by the addition of 0.5% citric acid (CN), 1% guar gum (GN) or 0.5% citric acid and 1% guar gum (CGN), and then it was incubated in a refrigerator for 3 days, and stored in a freezer for 1 month. Methods: The quality characteristics of these Naengmyeon noodles was evaluated based on total starch, resistant starch, water absorption, cooking loss, turbidity, in vitro starch hydrolysis, and in vivo glucose response. Results: There was no significant difference in the total starch, cooking loss, and turbidity. The resistant starch of GN (1.70%) and CGN (1.84%) was significantly increased when compared with that in Naengmyeon with no additives (N) and CN. In terms of water absorption, CN (86.01%) was the lowest in samples, followed by GN (92.17%), N (94.20%), and CGN (99.16%). CGN with high resistant starch was the lowest in in vitro starch hydrolysis in samples. However, it had no effect on the in vivo glucose response. In vitro starch hydrolysis exhibited a significant positive correlation (r=0.533; p<0.01) with in vivo glucose response. Conclusion: Therefore, future studies are needed to establish the standard for resistant starch contents in processed carbohydrate foods for delaying the increase in blood glucose. If this standard is established, it might help to develop processed foods for diabetic patients.

• Culinary science and hospitality research
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• v.23 no.3
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• pp.147-157
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• 2017

This study investigated quality characteristics and sensory properties of gluten-free bread using teff flour and various gums. The five samples used in this study were control (wheat flour), T (teff flour), TG (teff flour, guar gum), TX (teff flour, xanthan gum), and TGX (teff flour, guar gum, xanthan gum). Baking loss, moisture content, pH, salinity, brix, dough expansion, color value, texture property, and sensory property were measured for each sample. As a result, pH was the highest in TX at 6.11 and the lowest in the control at 5.77. Salinity was the highest in the control at 0.80% and lowest in TG at 0.04%. Brix was the lowest in TX at $1.10^{\circ}Bx$. While moisture content was the highest in the control at 43.58%, gluten-free breads using teff flour had no significant difference (p<0.05). Baking loss rate of bread was no significant difference among samples (p<0.05). Dough expansion rate by fermentation was the highest in the control at 108.89% and the lowest in T at 17.84%. L-value of crust had no significant difference (p<0.05). For L-value of crumb, the control was the highest at 64.34 and T was the lowest at 33.84. In texture properties analysis, hardness was the highest in TGX at 16.00 N and the lowest in the control at 2.87 N. There was no significant difference in springiness (p<0.05). Chewiness was the highest in TX and TGX. The result of sensory properties was that while there were no significant differences in color, salty taste, flavor, and overall acceptability, there was a significant difference in softness and sweetness (p<0.05). These results showed that use of teff flour and gums rather than using only teff flour for bread manufacturing can improve quality characteristics in dough expansion and texture properties. It is considered that xanthan gum or guar gum are appropriate on bread using teff for quality characteristics.

• Korean journal of food and cookery science
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• v.14 no.2
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• pp.168-176
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• 1998

The breadmaking characteristics of composite flour containing 30% of buckwheat and 70% of wheat with the addition of vital wheat gluten and water-soluble gums, were studied to establish the optimum formula for the development of buckwheat bread. The addition of vital wheat gluten or/and gums led to successful formation of buckwheat bread, giving loaf volume increase and improvement of sensory quality, especially texture determined by QDA (Quantitative Descriptive Analysis). Among those additives, xanthan gum showed the best volume expansion. Synergistic effects on bread quality were observed when the vital wheat gluten and xanthan gum or guar gum were used together. As buckwheat flour was substituted for wheat flour, gelatinization started early and the maximum viscosity increased measured by an amylography. The addition of gluten and gums caused the initial gelatinization to occur at a higher temperature and maximum viscosity to decrease.

• Journal of the Korean Society of Food Culture
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• v.22 no.1
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• pp.157-165
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• 2007

This study was designed to evaluate the effects of fructose(F) or sucrose(S) and guar gum intake on carbohydrate and lipid metabolism in 15-week-old male Goto-Kakizaki(GK) rats. Fifty rats were randomly assigned to 5 groups which were different in carbohydrate(25% of carbohydrate) and fiber(5% w/w) sources. The carbohydrate(CHO) sources of each group were comstarch(control group, 100% of CHO), fructose with cellulose(F), fructose with guar gum(FG), sucrose with cellulose(S), and sucrose with guar gum(SG). Each group was fed exterimental diet for 4 weeks. We measured food intake, body weight gain, adipose tissues weight and organs weight. We conducted oral glucose tolerance test(OGTT) and measured plasma insulin concentration to examine carbohydrate metabolism. To evaluate lipid metabolism, we measured the lipid profile of plasma, liver and feces. Food intake and weight gain of FG or SG groups tended to be less than those of F or S groups. Perirenal and epididymal fat pad weights of SG group were significantly lower than those of S group and those of FG group tended to be lower than those of F group. In OGTT, blood glucose values of F or S groups were significantly higher than those of C group, and FG or SG groups tended to be lower than those of F or S groups during the experimental time. The area under the curve(AUC) of C group was significantly highest among the groups, AUC and plasma insulin concentration of FG or SG groups tended to be lower than those of F or S groups. Plasma and hepatic triglyceride (TG) of FG and SG groups were significantly lower than those of F and S groups, plasma and hepatic total lipid(TL) and total cholesterol(TC) of FG and SG groups tended to be lower than those of F and S groups. Fecal TL, TG and TC of FG or SG groups tended to be higher than those of F and S groups. In conclusion, intake of guar gum should improve carbohydrate and lipid metabolism in partial substitution of fructose or sucrose for cornstarch in GK rats.

• Preventive Nutrition and Food Science
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• v.21 no.4
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• pp.367-372
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• 2016

To understand the effects of adding different gums (guar, xanthan, and locust bean gums) on naked barley flour (NBF), the rheological and pasting properties of NBF-gum mixtures were measured at different gum concentrations (0, 0.3, and 0.6% w/w). Steady shear rheological properties were determined by rheological parameters for power law and Casson models. All samples showed a clear trend of shear-thinning behavior (n=0.16~0.48) and had a non-Newtonian nature with yield stress. Consistency index, apparent viscosity, and yield stress values increased with an increase in gum concentration. Storage modulus values were more predominant than loss modulus values with all concentrations of gums. There is a more pronounced synergistic effect of elastic properties of NBF in the presence of xanthan gum. Rapid visco analyser pasting properties showed that the addition of gums resulted in a significant increase in the peak, breakdown, setback, and final viscosities, whereas the pasting temperature decreased.