Glucose Dialysis Retardation Index Research Articles

Effect of drying methods on physicochemical properties and in vitro hypoglycemic effects of orange peel dietary fiber

Dietary fiber plays an important role in the prevention and reduction of chronic diseases. This study evaluated the effect of drying methods (hot air drying, vacuum drying, and freeze-drying) on physicochemical properties and in vitro hypoglycemic effects of soluble and insoluble dietary fiber from orange peels. Freeze-drying significantly decreased the bulk density of the soluble and insoluble dietary fiber and increased the viscosity of soluble dietary fiber solutions (36.33 mPa s). Hot air drying caused a decrease in the molecular weight of soluble dietary fiber compared with freeze-drying. Freeze-dried dietary fibers exhibited a higher glucose adsorption capacity and glucose dialysis retardation index than fibers from other drying conditions, and this method enhanced the inhibitory effect of dietary fiber on α-amylase activity. Based on these results, freeze-drying is suggested for use in dietary fiber processing to obtain high-quality products for use in functional foods. Practical applications When formulating fiber-rich food products, the functional properties of dietary fiber must be considered. The functional properties depend on the processing conditions and physicochemical properties of the fiber. The results show that freeze-drying has significant advantages in improving physicochemical properties and in vitro hypoglycemic effects of dietary fiber, and the application of freeze-drying in dietary fiber processing could enhance its nutrient and commercial values.

Chemical composition and functional characteristics of dietary fiber-rich powder obtained from core of maize straw.

A novel dietary fiber (MsCDF) based core of maize straw (Core) was prepared by using high boiling solvent of sodium peroxide by high pressure pretreatment (HBSHP). The composition of MsCDF, and several physicochemical properties for MsCDF related to its nutritional quality were investigated. The results revealed that the MsCDF contains high contents total dietary fiber (TDF), soluble dietary fiber (SDF), insoluble dietary fiber (IDF) and two main monosaccharaides, xylose and glucose. Meanwhile, the studies of physicochemical properties of MsCDF indicated that MsCDF performed well water-holding capacity (WHC), oil-holding capacity (OHC), Swelling, solubility (SOL), Glucose dialysis retardation index (GDRI) and adsorption capacity on cholesterol. The results of this study serve as evidence that MsCDF can be used as a functional food additive, Core can be used as a crude material to produce MsCDF and the technology of HBSHP can be used to modify the physico-chemical properties of Core.

In vitro and In vivo Postprandial Glycemic Activity of Citrus limetta Peel Flour.

Background:Previous studies of Citrus spp. peel have shown hypoglycemic and antioxidant activities. Citrus limetta has been studied for its therapeutic properties. Diabetes mellitus (DM) is a health problem in Mexico and worldwide, that takes a vital importance due to its high incidence. Recently, scientists have searched natural sources to control the disease.Materials and Methods:In this study, we evaluated the in vitro hypoglycemic activity and in vivo postprandial glycemic effect of C. limetta peel flour by glucose adsorption and retardation assays as well as postprandial serum glucose levels using a group of female Balb-c mice, respectively.Results:C. limetta peel flour showed a glucose adsorption capacity of 16.58 mM, having a similar effect regarding the positive control. The glucose diffusion in the dialysate was elevated, with a glucose dialysis retardation index of 33.79% in a period of 3 h, showing similar results to positive control. Postprandial serum glucose levels in the animal group treated with C. limetta peel flour showed a glucose level of 41.4 mg/dL, being this value significantly lower than negative control group and similar to positive control. Toxicity tests showed good tolerance to the dose of 2000 mg/kg.Conclusion:C. limetta peel flour could act as a source of functional compounds for the control of DM.SUMMARY Citrus limetta peel flour showed a glucose adsorption capacity similar to the positive controlThe glucose diffusion in the dialysate was elevated, showing similar results to positive controlPostprandial serum glucose levels in the animal group treated with C. limetta peel flour showed a glucose level significantly lower than negative control group and similar to positive controlToxicity tests showed good toleranceC. limetta peel flour could act as a source of functional compounds for the control of diabetes mellitus. Abbreviations used: CIATEJ: Center for Research and Assistance in Technology and Design of Jalisco; DM: Diabetes mellitus; FGC: Final glucose concentration; GDRI: Glucose dialysis retardation index; IGC: Initial glucose concentration; OECD: Organization for Economic Cooperation and Development.

The physicochemical properties, in vitro binding capacities and in vivo hypocholesterolemic activity of soluble dietary fiber extracted from soy hulls.

Soluble dietary fibers (SDFs) have earned a healthy reputation due to their distinguished physiological functions. In this study, SDF was efficiently extracted from soy hulls using a phosphate-assisted subcritical water extraction method. The physicochemical properties, in vitro binding capacities and in vivo hypocholesterolemic activity of soy hull soluble dietary fiber (SHSDF) were evaluated. The results indicated that the major component of SHSDF was pectic polysaccharides, and with comparison to commercial oat β-glucan, SHSDF had favorable solubility, viscosity, water-holding ability (5.26 g water per g sample), and oil holding capacity (4.83 g oil per g sample). It also possessed good in vitro cholesterol-binding capacity (6.18 mg g-1 sample at pH 2 and 7.62 mg g-1 sample at pH 7), bile acid-binding capacity (3.3, 1.73 and 6.65 μM of GCA, GCDCA and GDCA per 100 mg of sample), glucose dialysis retardation index (64.76%), and in vivo hypocholesterolemic activity (16.88% and 35.28% reduction in serum total cholesterol and LDL level in rats, respectively). These data suggest that SHSDF has great potential in food applications, especially in the development of functional food ingredients.

Functional properties, phenolic constituents and antioxidant potential of industrial apple pomace for utilization as active food ingredient

Apple pomace is a waste biomass generated after apple fruit processing. In present investigation, efforts were made to comprehend influence of differently dried pomace on cell wall properties and phenolic profile. Different drying techniques were employed to remove moisture content from fresh apple pomace. Total dietary fiber yield (74%) and array of functional properties such as density, water and oil holding capacity, swelling capacity and glucose dialysis retardation index (36.91%) was found better in freeze dried fraction. The higher total phenolics (5.78±0.08mg GAE/g dry weight) content was also recorded in freeze dried fraction followed by oven and sun drying. The 50% aqueous acetone was found as more efficient solvent for extraction of phenolic constituents. RP-HPLC analysis has revealed presence of quercetin, phloridzin and phloretin as major phenolics. Thus, it is evident from the results that pomace generated at industrial scale can be utilized as a source of dietary food ingredient.

In vitro hypoglycemic effects and starch digestibility characteristics of wheat based composite functional flour for diabetics.

The associations between chronic feeding of high level of soluble/insoluble fibers and low serum glucose levels have been well documented. In the present study, composite flours were formulated using psyllium, barley and oat at two different levels [WPOB-I = wheat flour (75%), psyllium (5%), oat (10%) and barley (10%), WPOB-II = wheat flour (60%), psyllium (10%), oat (15%) and barley (15%)]. Chapaties were prepared from all formulations and various starch fractions were analyzed using controlled enzymatic digestion. The digestibility characteristics were studied using amylolysis kinetics employing porcine pancreatic α-amylase in vitro. Results showed that both the variations (WPOB-I & WPOB-II) had acceptable sensory qualities and had significantly lower (p ≤ 0.05) values for total starch (TS), rapidly digestible starch (RDS), resistant starch (RS), starch digestibility index (SDI) and rapidly available glucose (RAG) compared to control. Between the two variations, WPOB-I showed better starch digestibility characteristics with significantly lower (p ≤ 0.05) starch digestibility index (SDI). In case of amylolysis kinetics, both the variations significantly (p ≤ 0.05) inhibited α-amylase as reflected by lower glucose diffusion and significantly higher (p ≤ 0.05) glucose dialysis retardation index (GDRI) compared to control. It is inferred that, consumption of the composite flours might be helpful in establishing stable blood glucose pattern due to the redistribution of nutritionally important starch fractions and inhibition of carbohydrate digestion in the gastrointestinal tract.

Health related functional characteristics and antioxidant potential of mucilage (dietary fiber) from Zizyphus mauritiana fruits

The composition of Zizyphus mauritiana mucilage (ZMM) and several properties related to its nutritional quality were investigated. The ZMM with good water holding capacity (25.21g/g), swelling capacity (19.34mL/g), glucose dialysis retardation index and in vitro amylolysis kinetics indicate that it may have the capability in controlling the diabetes. Structural characteristics of ZMM were analyzed using the Fourier transform infrared (FT-IR) spectroscopy. In addition, the ZMM has the strong antioxidant potency against ABTS (16,587.32mmol trolox equiv./g), DPPH (5.27g mucilage/g DPPH), hydroxyl (76.13%) and superoxide (85.12%) radicals due to the presence of polyphenols (25.54mg GAE/g mucilage). Besides, the ZMM also inhibited the acetylcholine esterase (86.89%), tyrosinase (47.01%), α-amylase (70.13%) and α-glucosidase (87.14%) enzymes. These properties make the crude mucilaginous fraction from Z. mauritiana fruit an excellent candidate of potential nutraceutical and functional food.

In vitro hypoglycemic effects of Albizzia lebbeck and Mucuna pruriens

ObjectiveTo verify the antidiabetic potential of stem bark of Albizzia lebbeck (A. lebbeck) and seeds of Mucuna pruriens (M. pruriens) using various In vitro techniques. MethodsThe plant extracts were studied for their effects on glucose adsorption, diffusion amylolysis kinetics and glucose transport across yeast cells. ResultsBoth the plant extracts adsorbed glucose and the adsorption of glucose increased remarkably with an increase in glucose concentration. No significant (P≤0.05) differences were observed between the adsorption capacities of A. lebbeck and M. pruriens. In amylolysis kinetic experimental model the rate of glucose diffusion was found to increase with time from 30 to 180 min, and both the plant extracts demonstrated significant inhibitory effects on movement of glucose into external solution across dialysis membrane as compared to control. The retardation of glucose diffusion by A. lebbeck extract was significantly higher (P≤0.05) than M. pruriens. These effects were reflected with higher glucose dialysis retardation index values for A. lebbeck than M. pruriens. The plant extracts also promoted glucose uptake by yeast cells. The rate of uptake of glucose into yeast cells was linear in all the 5 glucose concentrations used in the study. M. pruriens extract exhibited significantly higher (P≤0.05) activity than the extract of A. lebbeck at all concentrations. ConclusionsThe results verified the antidiabetic potential of A. lebbeck and M. pruriens. The hypoglycemic effect exhibited by the extracts is mediated by increasing glucose adsorption, decreasing glucose diffusion rate and at the cellular level by promoting glucose transport across the cell membrane as revealed by simple In vitro model of yeast cells.

Functional and physiological properties of total, soluble, and insoluble dietary fibres derived from defatted rice bran.

Enzymatic- gravimetric method was used to obtain three fractions of dietary from defatted rice bran. The functional and physiological properties such as viscosity, cation exchange capacity (CEC), and glucose dialysis retardation index (GDRI), cholesterol and bile salt adsorption capacity of the resultant fractions were evaluated. Insoluble dietary fibre (IDF) and soluble dietary fibre (SDF) when compared showed that SDF exhibited significantly (p < 0.05) higher viscosity (2.35mPa.s), greater GDRI value (17.65%) at 60min and significantly lowered concentration of cholesterol at pH 7 (29.90%, p < 0.05). However IDF showed the highest CEC and its adsorption capacity of bile salt was higher than SDF (18.20% vs. 13.76%; p < 0.05), while CEC and cholesterol absorption capacity of TDF were similar to SDF. These properties indicate that rice bran soluble, insoluble and total fibres are functional ingredients which can be added to various food products and dietetic, low-calorie high-fiber foods to enhance their nutraceutical properties and health benefits.

Characteristics of fibre‐rich powder and antioxidant activity of pitaya (Hylocereus undatus) peels

SummaryThe contents of total dietary fibre (TDF), soluble dietary fibre (SDF), insoluble dietary fibre (IDF) and functional properties of fibre‐rich powders (FRP) from pitaya peels with different particle size (FRP80, FRP140 and FRP250) were determined. Results showed that FRP140 had higher TDF (79.37%) and SDF (33.07%) with a balanced ratio of SDF/IDF (1:1.32) and higher water‐holding capacity (54.20 g g−1), swelling capacity (50.63 mL g−1), oil‐holding capacity (2.65 g g−1) and glucose dialysis retardation index (62.83% at 60 min), compared with FRP80 and FRP250. Therefore, physiochemical properties of FRP140 were further investigated. SDF of FRP140 mainly contained rhamnose (4.95%) and galactose (1.98%), with 9.45% galacturonic acid, while IDF dominantly contained xylose (4.76%) and galactose (3.42%), with 18.54% klason lignin. Total phenolic content was 7.75 mg g−1 and mainly composed of salicylic acid (0.98 mg g−1) and protocatechuic acid (0.45 mg g−1). Furthermore, FRP140 showed significant reducing power, DPPH‐scavenging activity and nitrite‐scavenging ability.

In vitro hypoglycemic and cholesterol lowering effects of dietary fiber prepared from cocoa (Theobroma cacao L.) shells

Three dietary fiber (DF) powders; soluble dietary fiber (SDF), insoluble dietary fiber (IDF) and total dietary fiber (TDF) were prepared from cocoa bean shells (CBS) by enzymatic treatment. These DFs were evaluated for their effects on glucose adsorption, glucose diffusion, starch hydrolysis, cholesterol binding, sodium cholate binding and oil binding capacities using in vitro model systems by simulating gastric intestinal conditions. The results showed that SDF generally exhibited significantly (p < 0.05) higher glucose adsorption capacity (GAC), α-amylase inhibition activity, cholesterol and sodium cholate binding capacity, but less significant (>0.05) glucose dialysis retardation index (GDRI) and oil binding capacity, when compared with IDF and TDF which both showed similar effects. Moreover, it was discovered that the three CBS dietary fiber powders contained intrinsic antioxidants (phenolic compounds). The study suggested that CBS could be an alternative cheap source of DF with additional benefits. Thus, CBS fibers could be incorporated as low calorie bulk ingredients in high-fiber diet to reduce calorie and cholesterol levels and control blood glucose level.

Functional Properties and Characterization of Dietary Fiber from Mangifera pajang Kort. Fruit Pulp

A dried high fiber product from bambangan (Mangifera pajang Kort.) fruit pulp was prepared and evaluated for proximate composition, functional properties, and soluble and insoluble dietary fiber composition. Mangifera pajang fibrous (MPF) consisted of 4.7% moisture, 0.8% fat, 4% protein, and 30 mg total polyphenol per g of dry sample, and 9, 79 and 88% soluble, insoluble and total dietary fiber, respectively. Water holding capacity, oil holding capacity, swelling, and solubility were found to be 9 g/g dry sample, 4 g/g dry sample, 16 mL/g dry sample, and 11%, respectively. The glucose dialysis retardation index of MPF was approximately double that of cellulose fiber. Soluble dietary fiber contained mannose, arabinose, glucose, rhamnose, erythrose, galactose, xylose, and fucose at 1.51, 0.72, 0.39, 0.16, 0.14, 0.05, 0.04, and 0.01%, respectively, with 5.8% uronic acid, while insoluble dietary fiber was composed of arabinose (18.47%), glucose (4.46%), mannose (3.15%), rhamnose (1.65%), galactose (1.20%), xylose (0.99%), and fucose (0.26%) with 15.5% uronic acid and 33.1% klason lignin. These characteristics indicate that MPF is a rich source of dietary fiber and has physicochemical properties which make it suitable as an added ingredient in various food products and/or dietetic, low-calorie high-fiber foods to enhance their nutraceutical properties.

In vitro hypoglycemic effects of selected dietary fiber sources.

The physiological functions of dietary fiber and its role in health promotion and risk reduction of some chronic diseases has been well documented. In the present investigation, the effect of three dietary fiber sources, oats (OA), barley (BA) and psyllium husk (PH) on glucose adsorption, diffusion and starch hydrolysis were studied using in vitro techniques by simulating gastrointestinal conditions and compared with the commercial dietary fiber sources wheat bran (WB), acarbose (ACB) and guar gum (GG). The glucose binding capacity of all the samples was higher than WB and ACB at 5mM concentration. In all the samples, the diffusion of glucose was directly proportional to the time and diffusion rate was significantly lower (p ≤ 0.01) in the system containing various samples compared to control. Glucose dialysis retardation index (GDRI) was 100 for OA, BA and PH at 60min, at 120min the maximal GDRI was in PH. Whereas; WB and ACB exhibited maximal GDRI at 180 and 240min. All of these mechanisms might create a concerted function in lowering the rate of glucose absorption and as a result, decrease the postprandial hyperglycemia.

Effect of extraction method on chemical composition and functional characteristics of high dietary fibre powders obtained from asparagus by-products

Asparagus ( Asparagus officinalis L .) by-products, which represent around 50% of the processed vegetable, are a potential source of dietary fibre. The way that these by-products are treated affects the composition and functional properties of fibre-rich powders. Factors such as treatment intensity, solvent, and drying system were studied. Only the more soluble components (soluble sugars, uronic acids and proteins) showed significant differences. All the fibre-rich powders had high concentrations of TDF (62–77%). The IF/SF proportion decreased with the severity of treatment, in this way increasing the physiological quality of the fibre. Functional properties, namely water-holding capacity (WHC), oil-holding capacity (OHC), solubility (SOL), and glucose dialysis retardation index (GDRI), varied according to the preparation procedure. WHC and GDRI were higher in intensely extracted fibres; due to the effect of thermal processing. WHC showed values (11–20 ml water/g powder) similar to those described for other agricultural by-products, but OHC and GDRI were much higher (5–8 ml oil/g powder and 25–45%, respectively). These properties make fibre-rich powders from asparagus by-products a valuable source of dietary fibre to be included in the formulation of fibre-enriched foods.

Relationship between Physical and Hydration Properties of Soluble and Insoluble Fiber of Artichoke

Hot water and cellulase hydrolysis extraction methods were used to obtain soluble and insoluble fractions of dietary fiber (DF). Concentrates of the DF fractions were used to study their structure, physical properties (particle size, density, porosity, and oil adsorption capacity), hydration properties (swelling, water binding capacity, and viscosity), and glucose dialysis retardation index. Hydrolysis with cellulase modified the physical and hydration properties of the different samples analyzed, since this enzyme reduced the particle size in soluble and insoluble dietary fiber (SDF and IDF, respectively), while increasing the water binding capacity of IDF and decreasing that of SDF. Correlation studies carried out between the different properties analysed, showed that the behavior of hydrated fiber and the delay in glucose diffusion are determined by the physical properties of fiber. Keywords: Dietary fiber; functional properties; fiber extraction and artichoke