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Pullulan Is a Slowly Digested Carbohydrate in Humans

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Abstract

Pullulan is an extracellular polysaccharide excreted by the fungus Aureobasidium pullulans. To evaluate the glycemic and breath hydrogen responses and gastrointestinal tolerance to pullulan, nondiabetic healthy adult subjects (n = 28) were studied in a randomized, double-masked, crossover design. After an overnight fast, subjects consumed beverages containing 50 g of carbohydrate from either maltodextrin (control) or pullulan. Capillary blood glucose response was determined for 180 min postprandially. Breath hydrogen response was determined for 8 h postprandially. Compared with control, incremental peak blood glucose concentration was reduced (P < 0.01) when subjects consumed pullulan (4.24 +/- 0.35 vs. 1.97 +/- 0.10 mmol/L). In addition, pullulan reduced (P < 0.01) the positive incremental area under the glucose curve by 50%. When subjects consumed pullulan, the incremental blood glucose excursions were reduced (P < 0.01) at 15, 30, 45, 60 and 90 min, but were maintained above basal glucose concentrations at 150 and 180 min. At 180 min, the blood glucose concentration was higher (P < 0.05) when subjects consumed pullulan compared with control, supporting the hypothesis that pullulan is digested slowly. Breath hydrogen concentrations were increased (P < 0.01) at 3, 4, 5, 6, 7 and 8 h postprandially when subjects consumed pullulan. In the first 24-h postprandial period, the frequency and intensity of flatulence was higher (P < 0.05) after subjects consumed pullulan compared with control. In conclusion, pullulan attenuated the postprandial glycemic excursion compared with an equivalent maltodextrin challenge. Pullulan also increased breath hydrogen excretion and the incidence of gastrointestinal intolerance symptoms, indicating that a portion of pullulan was malabsorbed.

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... Contrary to the previous reports suggesting that pullulan is an indigestible carbohydrate (33)(34)(35)(36), it has been also shown that pullulan is slowly digested in human digestive system (33). It was found that pullulan is slowly digested in both the cooked and raw form. ...
... Contrary to the previous reports suggesting that pullulan is an indigestible carbohydrate (33)(34)(35)(36), it has been also shown that pullulan is slowly digested in human digestive system (33). It was found that pullulan is slowly digested in both the cooked and raw form. ...
... It was found that pullulan is slowly digested in both the cooked and raw form. Referring to the conclusions of this experiment postprandial blood glucose excursion after pullulan ingestion in humans was studied (33). The decrease of incremental peak blood glucose concentration after consumption of pullulan by nondiabetic healthy adult subjects was found in comparison with a control equivalent maltodextrin challenge. ...
Article
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Pullulan is a biocompatible polysaccharide obtained from black, yeast-like fungus Aureobasidium pullulans. This polymer is used to deliver various substances to the liver because of its specificity for this organ. Pullulan is internalized into hepatocytes in the process of asialoglycoprotein receptor mediated endocytosis. Recently, by reaction with glycidyltrimethylammonium chloride (GTMAC) we have successfully synthesized a cationically-modified pullulan (Pull-GTMAC). Pull-GTMAC exhibits some unique beneficial effects not found for its native counterpart. In this article we have reported for the first time that Pull-GTMAC administered orally to apoE-knockout mice (murine model of atherosclerosis) at a dose of 300 mg/kg b.w./day for 18 weeks showed anti-atherosclerotic activity reducing the area of atherosclerotic plaque. We have also found that Pull-GTMAC at a dose of 300 mg/kg b.w./day increases both the average daily mass of feces and the average number of droppings excreted by apoE(-/-) mouse in relation to the control sample derived from the mice fed with feed without the tested compound. However, the raw fat content in the feces of apoE-knockout mice was decreased in the group fed with the diet containing Pull-GTMAC towards control group of animals. Pull-GTMAC caused also statistically significant increase of mRNA level for LDL receptor in the apoE(-/-) mice liver after administration at a dose of 300 mg/kg/b.w./day for 18 weeks. However, the compound had no impact on lipid profile in serum of the tested mice. What is more, the studies on HepG2 cell line indicated an antiproliferative potential of cationically modified pullulan after 24 hour and 48 hour of incubation with the polysaccharide. In this paper we have shown for first time that cationically modified pullulan has antiatherogenic potential and influences on lipid metabolism.
... Figure 2 summarizes the process of literature search, identification, and screening, based on the PRISMA flow chart. Of these 14 papers, 4 investigated pullulan [22][23][24][25], 7 investigated xanthan gum [26][27][28][29][30][31][32] and three investigated dextran [33][34][35]. ...
... Wolf et al. [22] reported a randomized, crossover, double-masked, two-period, twotreatment study of a 474 mL juice-like beverage containing 50 g of carbohydrate from pullulan or maltodextrin control. They measured finger-prick blood glucose at 15, 30, 45, 60, 90, 120, 150, and 180 min postprandially. ...
... Four studies examined the overall tolerance of pullulan consumption. Wolf et al. [22] assessed gastrointestinal tolerance using questionnaires. The frequency and intensity of flatulence were significantly higher after subjects consumed pullulan compared with control. ...
Article
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Diabetes mellitus is a chronic condition characterized by increased blood glucose levels from dysfunctional carbohydrate metabolism. Dietary intervention can help to prevent and manage the disease. Food hydrocolloids have been shown to have favorable properties in relation to glycaemic regulation. However, the use of food hydrocolloids of bacterial origin to modulate glucose responses is much less explored than other types of hydrocolloids. We, therefore, carried out the first review examining the impact of intake of food hydrocolloids of bacterial origin (as a direct supplement or incorporated into foods) on glycemic response in humans. Fourteen studies met the inclusion criteria. They used either xanthan gum, pullulan, or dextran as interventions. There was a wide variation in the amount of hydrocolloid supplementation provided and methods of preparation. Postprandial blood glucose responses were reduced in half of the studies, particularly at higher intake levels and longer chain hydrocolloids. When xanthan gum was added to the cooking process of muffins and rice, a significant reduction in postprandial blood glucose was observed. The use of these hydrocolloids is potentially effective though more research is needed in this area.
... Pullulans are naturally occurring fermentation products produced by Aureobasidium pullulans, a black yeast found throughout all ecological niches including forest soils, fresh water and seawater, and plant and animal tissues (12,13). Pullulans are linear polysaccharides consisting of three R-(1-4) linked glucose molecules that are repeatedly polymerized by R-(1-6) linkages on the terminal glucose, resulting in a stair-step structure (14,15). ...
... Pullulans are linear polysaccharides consisting of three R-(1-4) linked glucose molecules that are repeatedly polymerized by R-(1-6) linkages on the terminal glucose, resulting in a stair-step structure (14,15). The stair-step structure resulting from glycosidic linkages in pullulans hinders hydrolysis by enzymes, making them low-digestible carbohydrates (13). ...
... However, other research conducted with pullulans indicates otherwise. Wolf et al. (13) found pullulan (MW 100,000) to be extensively hydrolyzed in vitro, but this hydrolysis occurred slowly over time. They concluded that pullulan was slowly digested and would result in a low glycemic response. ...
... The different processes used to produce SCF result in fractions with varying degrees of digestion resistance because of increased α-1,6 glycosidic bonds formed during their production. Similarly, the stair-step structure of pullulans, resulting from α-1,6 glycosidic linkages, hinders hydrolysis by enzymes, making them low-digestible carbohydrates (Wolf et al., 2003). Sorbitol, a sugar alcohol, is slowly absorbed into the body from the gastrointestinal tract and is metabolized by the liver, largely as fructose. ...
... These data indicate that pullulan was digestible by hydrolytic enzymes and resulted in glucose release. Wolf et al. (2003) and Knapp et al. (2010) found pullulans of different MW to be extensively hydrolyzed in vitro. However, Wolf et al. (2003) found the hydrolysis to occur slowly over time and concluded that pullulan was a slowly digestible carbohydrate with the potential to positively impact glycemic response. ...
... Wolf et al. (2003) and Knapp et al. (2010) found pullulans of different MW to be extensively hydrolyzed in vitro. However, Wolf et al. (2003) found the hydrolysis to occur slowly over time and concluded that pullulan was a slowly digestible carbohydrate with the potential to positively impact glycemic response. ...
Article
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The objective of these experiments was to measure in vitro hydrolytic digestion and glycemic and insulinemic responses of select carbohydrate blends, all containing the novel carbohydrate, soluble corn fiber (SCF). Two SCF that varied in their method of production were used to formulate the carbohydrate blends. One set of blends contained a SCF that was spray-dried (SCFsd), then blended with different amounts of either pullulan, sorbitol, or fructose. The other set of blends contained a SCF produced using longer evaporation time (SCF), then blended with different ratios of pullulan, sorbitol, and fructose. Free sugar concentrations found in the individual SCFsd and SCF substrates were low, but varied. Spray-dried soluble corn fiber had a lower free sugar concentration compared with SCF (2.8 vs. 14.2%). Glucose was the main free sugar found in both SCFsd and SCF, but at different concentrations (2.7 vs. 12.7%, respectively). The majority of the SCFsd blends were completely hydrolyzed to their monosaccharide components. Glucose accounted for most of the hydrolyzed monosaccharides for SCFsd and all the SCFsd blends. Hydrolyzed monosaccharide concentrations for the SCF:pullulan:sorbitol:fructose blends followed similar trends to the SCFsd blends where greater percentages of fructose and sorbitol resulted in lower hydrolyzed monosaccharide concentrations. The SCFsd blends had intermediate to high amounts of monosaccharides released as a result of in vitro hydrolytic digestion. The SCFsd:pullulan blends were more digestible in vitro (approximately 91%; P < 0.05) than SCFsd:fructose or SCFsd:sorbitol. Total released monosaccharides were high in SCFsd blends containing either 50% fructose or sorbitol, but the combination resulted in lower concentrations of glucose released (P < 0.05). The SCF:pullulan:sorbitol:fructose blends also had intermediate to high released monosaccharides as a result of in vitro hydrolytic digestion. All SCF blends resulted in lower glycemic and insulinemic responses compared with the maltodextrin control (P < 0.05) using a canine model. The addition of pullulan reduced the glycemic response compared with maltodextrin at all concentrations, but only 50:50 SCFsd:pullulan resulted in a lowering of the glycemic response compared with SCFsd alone (P < 0.05). The addition of fructose and sorbitol in the blends had the greatest impact on glycemic and insulinemic responses, even at concentrations as low as 5% of the blends. Overall, SCF and their blends may prove beneficial as components of low glycemic foodstuffs.
... New developments in food and nutritional science have led to the conclusion that slowing down the rate of digestion of glucose from ingested carbohydrate sources helps to blunt glycemia, reduces insulin requirements, and causes satiety (FAO/WHO, 1997). The food industry has been developing a new, slowly digestible carbohydrate (SDC) (Thorburn et al., 1987;Bjrck and Asp, 1994;Wrsch, 1994;Wolf et al., 2003). Some examples of commercially available products include isomaltulose, trehalose, oligoalternan, pullulans, sucromalt, as well as other slowly digestible syrups. ...
... Some examples of commercially available products include isomaltulose, trehalose, oligoalternan, pullulans, sucromalt, as well as other slowly digestible syrups. All of these products claim to have a slow and extended postprandial level of glucose after intake, although they differ in molecular structure, functional properties, and potential application in conjunction with SDS (Wrsch, 1994;Asp, 1995;Heymann et al., 1995;Scheppach et al., 2001;Sparti et al., 2002;Wolf et al., 2003). The present review focuses on SDS as an SDC and analyzes its digestibility, preparation, physiological effects, and potential application. ...
Article
Full-text available
The link between carbohydrate intake and health is becoming increasingly important for consumers, particularly in the areas of glycemic index (GI) and extended energy-releasing starches. From a physiological point of view, slowly digestible starch (SDS) delivers a slow and sustained release of blood glucose along with the benefits resulting from low glycemic and insulinemic response. SDS has been implicated in several health problems, including diabetes, obesity, and cardiovascular diseases (metabolic syndromes). It may also have commercial potential as a novel functional ingredient in a variety of fields, such as nutrition, medicine, and agriculture. The present review assesses this form of digestion by analyzing methods to prepare and evaluate SDS, factors affecting its transformation, its health benefits, and its applications.
... It should be noted that in addition to acting as a preserving delivery vehicle, pullulan may have a beneficial effect on the surrounding microbiota (Chlebowska-Smigiel et al., 2017;Chlebowska-Śmigiel et al., 2019;Hong et al., 2019;Leathers, 2003;Sugawa-Katayama et al., 1994;Wolf et al., 2003). For instance, Wolf et al. (Wolf et al., 2003) showed that pullulan is a slowly digested carbohydrate in humans and some have demonstrated that pullulan can function as a prebiotic (Hong et al., 2019), and promote the growth of beneficial bacteria such as bifidobacteria (Leathers, 2003;Sugawa-Katayama et al., 1994). ...
... It should be noted that in addition to acting as a preserving delivery vehicle, pullulan may have a beneficial effect on the surrounding microbiota (Chlebowska-Smigiel et al., 2017;Chlebowska-Śmigiel et al., 2019;Hong et al., 2019;Leathers, 2003;Sugawa-Katayama et al., 1994;Wolf et al., 2003). For instance, Wolf et al. (Wolf et al., 2003) showed that pullulan is a slowly digested carbohydrate in humans and some have demonstrated that pullulan can function as a prebiotic (Hong et al., 2019), and promote the growth of beneficial bacteria such as bifidobacteria (Leathers, 2003;Sugawa-Katayama et al., 1994). Sugawa-Katayama et al. (Sugawa-Katayama et al., 1994) also fed some rats on diets containing 10% pullulan or 10% polydextrose or 10% pectin and took the fecal contents under anaerobic conditions to count the proportion of Lactobacillus and Bifidobacterium in cecal microflora. ...
Article
Encapsulation of bacteria into a polymer matrix can potentially enhance the delivery of probiotics. In this study, we present a multilayer electrospun construct to facilitate enhanced delivery of probiotics, where the internal layer is loaded with bacterial cells and the external layers sandwich the internal layer for increased protection and potential mucoadhesion properties. In this proof of concept study, Lactobacillus rhamnosus GG (LGG), which is a robust and well-studied probiotic strain, was encapsulated into pullulan nanofibers, with two electrospun PLGA (Poly-lactic-co-glycolic acid) layers covering it. According to our in vitro study, there was a large decrease in the viability of LGG released from the monolayer sample (LGG:pullulan). However, the multilayer construct maintained excellent viability and an acceptable storage potential. Our in vivo competition study showed that LGG, delivered by multilayer construct, were able to survive intestinal transit and were recovered from all segments of the intestine. Not only did the multilayer construct perform as well as non-encapsulated spray-dried cells in terms of viability and establishment of LGG, but it also showed some cases of increased LGG colonization from fibers in jejunum and cecum compared to spray-dried LGG three days after dosage. We believe, the multilayer construct has the potential to enhance the delivery of the strains that require additional protection, and can benefit from mucus embedment with the help of the covering layers. Particularly, the use of electrospun fibers for the protection of next-generation probiotics sensitive to oxygen and/or gastric conditions could have major commercial interest.
... It is noteworthy that Mahdavinia et al. prepared porous polyacrylamide hydrogel by leaching calcium carbonate during the synthesis process [2]. Pullulan is a bacterial polysaccharide, extracted from the fermentation medium of the Aureobasidium pullulans, linked glucose molecules that are repeatedly polymerized by α-1,6 linkages on the terminal glucose, contributes to the structural flexibility and high solubility of pullulan [11][12][13][14]. Besides the common advantages of natural polysaccharides, such as non-toxic, biocompatible and biodegradable, the distinctive linkage pattern of pullulan endows it with unique physical properties, including excellent water solubility, high-water-absorbing capability, adhesive properties and the capability to form strong resilient films and fibers [15]. ...
Article
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A pullulan-graft-polyacrylamide semi-IPN hydrogel was prepared by free radical polymerization and became porous by the incorporation of calcium carbonate and a subsequent acid treatment. The product was characterized by Fourier transform infrared spectroscopy, thermal gravimetric analysis, and optical microscopy to confirm the formation of porous hydrogels. In addition, the effect of several variables such as monomer, crosslinker, initiator and porogen concentration on swelling ratio and porosity of hydrogels was explored. The maximum porosity and swelling capacity in the optimized conditions were found to be 96.5% and 3089%, respectively. The prepared hydrogel was utilized as a selective adsorbent of Hg(II) ions from an aqueous solution with fast and high removal efficiency. The mercury sorption capacity under non-buffered conditions is achieved 8.6 mmol/g in the first 90 min via colorimetric method. The mechanism of adsorption was well presented using a pseudo-second-order kinetic model. Furthermore, the isothermal adsorption equilibrium data were fitted to Freundlich model. Finally, the mercury-loaded hydrogel was regenerated without losing its original activity and stability.
... Reverse micellization [54,55] Polyanhydrides Safe, biodegradable. ...
Article
Mucosal administration of vaccines is one of the most popular approaches to induce desired immunity against various types of antigen and microbial in central as well as peripheral blood and in most external mucosal surfaces. The oral route is a preferred choice over parenteral route for this purpose mainly due to an ease of administration and therefore, for the possibility of covering large population for mass immunization. Different strategies of mucosal vaccination aimed to prevent colony formation and infection by pathogens and block its development. But a major concern with these vaccines is the degradation of protein components in stomach due to physiological conditions and gastric enzymes. Therefore, surface modified nanoparticles offer a better and stable alternative for efficient delivery and better activation of required immune responses. Natural and synthetic polymers are used to prepare nanoparticulate carrier systems for the development of oral mucosal vaccines. Amongst these, biodegradable polymers based nano-particulate carriers have been explored extensively for the development of delivery systems. Present review summarizes possible approaches and mechanisms for the systemic immunization by oral vaccines and critically discusses various polymers used, different strategies of surface modification to achieve targeting of antigen loaded nanoparticulate carrier at cellular level that are essentially required for a successful mucosal vaccination approach, and future prospects of nanoparticulate system as adjutants in oral mucosal vaccination.
... Semblable à la méthode de Goni, seule l'α-amylase est utilisée dans la mesure et cette méthode n'a pas été vérifiée non plus par des tests in vivo. Elle ne peut cependant pas être utilisée pour mesurer les fractions de digestion de certains polymères de glucose (ex du pullulane), résistants, de par leur structure, à l'α-amylase [367]. De plus, l'utilisation du maltose comme base pour représenter les fractions d'amidon n'est pas scientifiquement exacte car le maltose n'est qu'une petite partie des produits d'hydrolyse provenant de la digestion par l'α-amylase [357]. ...
Thesis
L’hyperglycémie chronique est impliquée dans le développement de complications associées au DT2 et la variabilité glycémique (VG) apparait comme une composante à part entière de l'homéostasie du glucose. Les mesures hygiéno-diététiques, en première ligne dans la prise en charge du DT2, passent entre autres par une modification de l’alimentation, dans laquelle les glucides occupent une place prépondérante. Au-delà de la quantité, la qualité des glucides a été mise en avant comme ayant un impact déterminant sur les excursions glycémiques. Notamment, la digestibilité des produits à base d’amidon pourrait alors avoir un impact sur le contrôle glycémique chez les patients atteints de DT2. Mais il y a aujourd’hui un réel besoin d’apporter une caractérisation des produits plus complète sur cet aspect et de mener des études de faisabilité et d’efficacité de tels régimes modulant la digestibilité de l’amidon. Mes travaux de thèse montrent qu’il est possible de concevoir un régime riche en amidon lentement digestible (SDS), grâce à des choix de produits amylacés disponibles dans le commerce, des conseils de cuisson et des recommandations adaptées. Pour la première fois, nous avons montré que le contrôle de la digestibilité de l'amidon de produits amylacés avec des instructions de cuisson appropriées dans une population atteinte de DT2 augmentait la consommation de contenu en SDS dans un contexte de vie réelle et que ce type de régime était bien accepté dans telle population. De plus, nous avons montré que l’augmentation du rapport SDS/glucides était associée à une amélioration du contrôle glycémique postprandial et qu’il existait une corrélation linéaire inverse entre les paramètres de VG et la teneur en SDS. La mise en œuvre d’un régime riche en amidon lentement digestible dans une population atteinte de DT2, a montré une différence significative sur le profil de variabilité glycémique, mais également sur les excursions glycémiques postprandiales, évalués par le CGMS, en comparaison avec un régime pauvre en amidon lentement digestible. Ce type de régime a également permis aux patients d’atteindre des cibles glycémiques postprandiales plus appropriées. Grâce à un travail de revue de la littérature, nous avons mis en évidence que la déviation standard (SD), le coefficient de variation (CV), l’amplitude moyenne des excursions glycémiques (MAGE) et la moyenne glycémique (MBG) étaient les paramètres de VG les plus étudiés en termes de relation avec les paramètres de diagnostic du DT2 et les complications liées au DT2 et qu’ils montraient des relations fortes, en particulier avec l’HbA1c. Dans les études interventionnelles, nous avons pu voir que la SD, le MAGE et le temps dans la cible (TIR) étaient les paramètres les plus utilisés comme critères d’évaluation, montrant des améliorations significatives suite aux interventions pharmacologiques ou nutritionnelles, souvent en lien avec des paramètres de contrôle glycémique comme l’HbA1c, la glycémie à jeun ou en postprandial. La VG apparaît donc comme une composante clé de la dysglycémie du DT2. Au-delà de son utilisation par le patient comme support du contrôle glycémique, le CGMS apparait comme un outil pertinent en recherche clinique pour évaluer l’efficacité des interventions même si à ce jour, il reste encore très peu utilisé pour les interventions nutritionnelles. Des études plus approfondies seront cependant nécessaires pour confirmer l'impact bénéfique de telles interventions alimentaires à long terme. Nous avons conçu une étude à plus grande échelle pour étudier l'impact à long terme d’un régime riche en SDS sur la variabilité et le contrôle glycémiques (CGMS) et les complications et comorbidités associées chez le patient atteint de DT2. La modulation de la digestibilité de l'amidon dans l'alimentation pourrait alors être utilisée comme un outil nutritionnel simple et approprié pour améliorer l'homéostasie glucidique au quotidien dans le DT2.
... Pullulan is being used extensively in the food industry as a food ingredient for over 20 years in Japan, and has Generally Regarded As Safe (GRAS) status in the USA USFDA, 2002). Pullulan which was earlier considered as an indigestible polymer was shown to be slowly digestible and found application as a low-calorie food additive providing bulk and texture Wolf 2005). Recently pullulan is also being investigated for its biomedical applications in various aspects like targeted drug and gene delivery, tissue engineering, wound healing and in diagnostic imaging using quantum dots Rekha and Sharma, 2007). ...
... Pullulan is a water-soluble, linear polysaccharide consisting of three -1, 4-linked glucose molecules polymerized by -1, 6 linkages on the terminal glucose [99]. Pullulan is a fermentation product of the yeast Aureobasidium pullulans. ...
... Maltodextrin was used as a control for each glycemic response test because it is highly digestible, rapidly absorbed, and produces a constant glycemic response (Wolf et al., 2003). The carbohydrates were not all evaluated in the same trial, so Malt was used in each trial as a control to calculate a relative response to the test carbohydrate in all periods. ...
Article
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The objective of this research was to measure in vitro hydrolytic digestion, glycemic and insulinemic responses in dogs, and true ME (TMEn) content of select soluble corn fibers (SCF) in roosters. The first generation (G1) SCF included hydrochloric acid-treated corn syrup (G1-CS-HCl), an SCF with an increased total dietary fiber (TDF) content (G1-SCF-HCl), an SCF that was spray-dried (G1-SCF-SD), and a hydrogenated SCF (G1-SCF-hydrog). The second generation (G2) SCF included those prepared using phosphoric acid catalyzation in both a liquid [G2-SCF-phos (Lq)] and powder [G2-SCF-phos (Pw)] form, and SCF that were prepared using hydrochloric acid catalyzation in both a liquid [G2-SCF-HCl (Lq)] and powder [G2-SCF-HCl (Pw)] form. Also, in the G2 set of samples were SCF prepared using the same method, but in 3 separate batches, all of which contained 70% TDF and 15% sugars. Two were in liquid form [G2-SCF-phos+HCl (Lq1)] and [G2-SCF-phos+HCl (Lq2)], and one in powder form ([G2-SCF-phos+HCl (Pw)]. A lower sugar form (80% TDF and 5% sugar) of SCF was also evaluated (G2-SCF-low sugar). Glucose was the major free sugar and bound monosaccharide in all SCF except for G1-SCF-hydrog that had greater concentrations of sorbitol. All SCF had intermediate to low amounts of monosaccharides released as a result of in vitro hydrolytic digestion, with glucose being the primary sugar component released. The G1-SCF were more digestible in vitro (approximately 50%) compared to G2-SCF (approximately 32%). All SCF had attenuated glycemic responses in adult dogs compared to a maltodextrin control (P < 0.05). The G2-SCF, on average, had lower glycemic responses and TMEn values in roosters than G1-SCF. All SCF had low free sugar concentrations with varying degrees of resistance to digestion, reduced caloric content, and attenuated glycemic and insulinemic responses in adult dogs. These ingredients are potential candidates for inclusion in reduced calorie and low glycemic canine diets.
... It is highly soluble in cold and hot water resulting in clear viscous solutions. Nontoxic, non-mutant and non-carcinogenic properties have also been reported (Dixon et al., ;Kumar et al., 2012;Mishra et al., 2011;Rekha and Sharma, 2007;Singh et al., 2008;Wolf et al., 2003). Initially, it has been widely explored as a food packing edible film polymer due to its film forming, oxygen barrier, moisture retention and antifungal ...
Article
The effect of different plasticizers (glycerol, vitamin E TPGS and triacetin) and their concentrations on the physico-mechanical properties of pullulan based oral films was studied. A full factorial (3²) design of experiments was used. Elastic modulus, tensile strength, elongation at break and disintegration time were selected as response variables. Modulated differential scanning calorimeter (MDSC) was used for determining glass transition temperature (Tg) of pullulan films. The surface morphology of films was evaluated by SEM, while ATR-FTIR was used to obtain a molecular level understanding of polymer-plasticizer interactions. The DoE analysis allowed for the modelling of tensile strength and elongation at break. The highest elongations were observed in glycerol at 20% w/w. Majority of the films disintegrated within one minute without significant differences. ATR-FTIR spectra of pullulan alone and different plasticizer blend films show characteristic molecular interactions. The present study concluded that glycerol is suitable plasticizer compared to others for manufacturing pullulan based oral films.
... These special properties of PUL make it widely used in food, material, and pharmaceutical industries (Prajapati, Jani, & Khanda, 2013;Singh, Saini, & Kennedy, 2008). It's worth noting that PUL can be slowly digested and treated as dietary fiber because of its resistance to mammalian amylases, which resulting in a gradual rise in blood glucose level in humans (Wolf, Garleb, Choe, Humphrey, & Maki, 2003). Therefore, PUL may be supplemented into dietetic foods prepared for diabetics or special group who have impaired glucose tolerance (Singh, Saini, & Kennedy, 2008). ...
Article
The in vitro enzymatic digestibility of rice starch (RiS) was investigated in the presence or absence of pullulan (PUL) using the classic Englyst method and complemented by the analysis of the digestion kinetic. PUL induced a significant increase of the sum of slowly digestible starch (SDS) and resistant starch (RS) contents from 21.24% to 38.11% with a concomitant decrease of the rapidly digestible starch (RDS) content when 0.50% PUL was added. Both of the hydrolysis kinetic parameters, C∞ and k, decreased with the increasing of PUL, indicating the deceleration of hydrolysis rate by the incorporation of PUL. As evidenced by the changes of the crystalline characteristics and morphologies of fresh starch pastes with the help of X-ray diffraction (XRD), optical microscope, and confocal laser scanning microscopy (CLSM), the inhibitory effect of PUL on gelatinization of starch and the coating effect of PUL on the surface of starch granules were hypothesized to be responsible for the reduced starch digestibility in the present work.
... A survey of the World patent Index in 1983 revealed that over 150 inventions are related to this polysaccharide, mostly on its new applications (LeDuy et al., 1988). Literature has been surveyed from 2000 to 2008 and it revealed ten new inventions related to production and pharmaceutical applications of the pullulan (Thorne et al., 2000(Thorne et al., , 2002Cade et al., 2003;Ikewaki et al., 2005;Scott et al., 2005;Wolf, 2005;Boyd et al., 2006;Gaddy & Patton, 2006;Leung et al., 2006). Bauer (1938) fi rst discovered the production of pullulan on the surface as a slimy product by Aureobasidium pullulans, later the name was given by Bender et al. (1959). ...
... Therefore, it has been proposed to use it as a component of low-calorie foods, and in dietary snacks for diabetics [5,6]. In human large intestine, undigested pullulan may probably undergo fermentation by stool microflora to form short chain fatty acids [7,8]. ...
Article
Background: Pullulan is a microbial polysaccharide of low energy value, which can component of low-calorie foods and in dietary snacks for diabetics. The objective of the study was to determine the effect of pullulan on the growth and fermentation activity of selected human intestinal bacteria. Methods: Commercial pullulan purchased from Focubase (China) of a molecular weight of 100,000 Da constituted as experimental material. Food grade pullulan 99% purity. Two control media were prepared: the first standard RCM composed of (g/100 ml): 0.5 glucose, 0.1 soluble starch, 1.0 peptone, 1.0 meat extract, 0.3 yeast extract, 0.3 sodium acetate, 0.05 cysteine hydrochloride, 0.5 NaCl, pH 6.8; and the second modified RCM, wherein the soluble starch was replaced by increased glucose concentration to 2.0% (RCM+G). Experimental medium was the modified RCM medium, wherein the soluble starch and glucose were replaced by pullulan at a concentration of 2.0% (RCM+P). Stool suspensions were prepared from fresh stool samples (1 g) in peptone water (9 g), which were previously homogenized. Then, suspensions at a volume of 300 µl were transferred to the media (RCM, RCM+G, and RCM+P). After mixing, flasks were placed in anaerobic tubes with AnaeroGenTM 2.5 l sachets. Incubation of samples was carried out at 37°C for 48 h. Results: The number of Bifidobacterium, Lactobacillus, and Escherichia coli bacteria, as well as pH and total acidity of the culture during 0, 24, and 48 h were measured. It was found that the numbers of bacteria of the Bifidobacterium and Lactobacillus genus in medium with pullulan were one logarithmic cycle lower in comparison to their numbers in the control media. Higher total acidity (1.48 g/100 ml) of pullulan culture in comparison to the control media was obtained (1.10 and 0.60 g/100 ml), and lower pH values than RCM medium, particularly 4.15 and 4.70, respectively. Pullulan exhibited selective effect on the natural microflora of the colon. Increase in the fermentation activity of bacteria in medium with pullulan favorably influenced modification of the composition of gut microbiota. Conclusion: In summary, pullulan exhibited a selective effect on the natural microflora of the infants' colon. Although no stimulating effect of pullulan on the growth of Bifidobacterium and Lactobacillus was observed, their increased acidifying activity, which probably was the cause of reduction in the number of E. coli bacteria, was confirmed.
... Pullulan is water-soluble, linear polysaccharides that consist of three a-1,4-linked glucose molecules polymerized by a-1,6 linkages on the terminal glucose. Pullulan is a fermentation product of the yeast Aureobasidium pullulans [54]. ...
Article
Mucosal administration of vaccine is most prevalent way to induce desired immunity against various types of antigen and microbial in central and in addition, the peripheral blood in most external mucosal surface. Mucosal delivery of vaccine provides both humoral and cellular responses against mucosal infection. Mucosa, which are exposed to heavy loads of commensal and pathogenic microorganism, are one of the main region where infections are built up, also, thus have frontline status in immunity, making mucosa perfect site for vaccines application. The nasal route is favoured over parenteral route due to ease of administration, protection of antigen from degradation and induces sIgA which is not produced by systemic immunity. Natural and synthetic polymers are utilized to get nanoparticles carrier systems for development of nasal mucosal antibodies. The present review summarized the recent development in the field of vaccine delivery by means of mucoadhesive polymeric carriers. This review also describes the recent patent conceded for mucosal immunization utilizing these polymeric carriers.
... In some cases, depending on the biosynthetic origins, maltotetraose subunits may substitute predominant maltotriose subunits [1]. Commercially available PUL is an odorless, tasteless, white colored powder that is highly water soluble, non-toxic, stable to most metals, and resistant to changes in temperature and solution pH [2][3][4][5][6][7][8][9][10]; PUL is also inert to mammalian amylases and possesses prebiotic properties, thus it is used as low calorie, dietary fibers in health foods and functional food [2,[10][11][12][13][14][15]. Recently, in the attempt to expand food resources and develop new food formulations, PUL fibers and fibrous mats were electrospun in combination with caseinates and pectin in our laboratory [16,17], along with several other food-grade biopolymers from the groups of protein, polysaccharides, and lipids [18]. ...
Article
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There is an increasing interest in applying the technology of electrospinning for making ultrafine fibers from biopolymers for food-grade applications, and using pullulan (PUL) as a carrier to improve the electrospinnability of proteins and other naturally occurring polyelectrolytes. In this study, PUL solutions containing NaCl or Na3C6H5O7 at different concentrations were electrospun. The inclusion of salts interrupted the hydrogen bonding and altered solution properties, such as viscosity, electric conductivity, and surface tension, as well as physical properties of fibers thus obtained, such as appearance, size, and melting point. The exogenous Na+ associated to the oxygen in the C6 position of PUL as suggested by FTIR measurement and was maintained during electrospinning. Bead-free PUL fibers could be electrospun from PUL solution (8%, w/v) in the presence of a 0.20 M NaCl (124 ± 34 nm) or 0.05 M Na3C6H5O7 (154 ± 36 nm). The further increase of NaCl or Na3C6H5O7 resulted in fibers that were flat with larger diameter sizes and defects. SEM also showed excess salt adhering on the surfaces of PUL fibers. Since most food processing is not carried out in pure water, information obtained through the present research is useful for the development of electrospinning biopolymers for food-grade applications.
... It is therefore assumed that the un-absorbed carbohydrate determined through breath H 2 for these foods was also not related to the glycemic response. Additionally, as discussed by Wolever (2006) concerning the ileostomy model, the amount of carbohydrate malabsorbed measured by breath hydrogen may account for some of the reduction in glycemic response, but cannot explain all of the reduction, as indicated in Wolf et al. (2003). ...
... Lentinus edodes [61][62][63] Glomerellan Glomerella cingulata [64] Pestalotan Pestalotia sp. [65] Schizophyllan Schizophyllum commune [66][67][68][69] Scleroglucan Sclerotium glucanicum [56,70] Grifolan Grifola frondosa [71,72] Pullulan Aureobasidium pullulans [73][74][75][76] Pachyman Poria cocos [77][78][79] Pleuran Pleurotus ostreatus [80,82] Chitin Cunninghamella elegans [32] Mucor rouxii [83] Rhizopus oryzae [84] Agaricus bisporus [85] Ganoderma lucidum [86] Chitosan Aspergillus niger [16] Candida albicans [16] Gongronella butleri [29] Lentinus edodes [16] Mucor rouxii [40,43,87] Penicillium sp. [18] Rhizopus oryzae [16,33,34] CGC and/or ChCG Aspergillus niger [10,88,89] Aspergillus fumigatus [90] Armillariella mellea [91,92] Morchella esculenta [92] Pichia pastoris [12] Mucor rouxii [88] Saccharomyces cerevisiae [93] Schizophyllum commune [94] Gongronella butleri [95] Pleurotus ostreatus [96] Agaricus bisporus [97] Mannans Galactomannan Aspergillus fumigatus [19] Acidic galactomannan Lecanicillium muscarium [21] Xylomannan Auricularia polytricha [28] Polymers Sources References ...
Chapter
Biodegradable and biocompatible polysaccharides of fungal origin, such as cell wall polysaccharides (e.g., chitin, chitosan, glucans, mannans) and extracellular polysaccharides (EPS) (e.g., pullulan, scleroglucan), have been widely studied and proposed for a wide range of applications. Due to their properties, such polysaccharides have attracted increasing interest for pharmaceutical and biomedical applications, including in immunology and drug delivery systems. Many polysaccharides of fungal origin are currently being investigated for such uses in in-vitro and in-vivo clinical trials. Moreover, there are already several commercial fungal polysaccharides available, although most of them are marketed as natural products and their clinical use is still not widespread.
... Gradinaru etal 2003 studied the stability of freeze dried anthocyanin from H. Sabdariffa encapsulated with pullulan and kept under different water activities and temperatures. Although improved stability was recorded, pullulan (an extra cellular polysaccharide excreted by the fungus Aureobasidiumpullulan) is slowly digested in humans resulting in symptoms of gastrointestinal intolerance (Wolf et al 2003).The stability of freeze dried Roselle anthocyanins microencapsulated separately in dried maltodextrin D.E 10,maltodextrinD.E 20 and gum arabic was evaluated by Selim et al. (2008). They found maltodextrin D.E 20 to be most effective under all storage conditions and in food products. ...
Article
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The significance of natural food colorants such as Roselle anthocyanins had been known for decades. However their stability in and out of food systems is still a challenge. This work was aimed at mitigating this phenomenon. Various solvent extracted, microencapsulated in native corn starch and freeze dried samples[ethanol acidified with 1% citric acid (FDMEE), 2% citric acid solution (FDMCE) as well as distilled water (FDMWE) ] were prepared using standard techniques. These were kept under room temperature conditions for eight weeks and physicochemical evaluations conducted periodically. Some of these were utilized (1% inclusion) in the production of jam and evaluated by a 30 man sensory panel. Colour intensity indicated by Chroma Values (a *) of microencapsulated samples were: FDMEE (2.20 + 0.01), FDMCE (3.05 + 0.02) and FDMWE (1.98 + 0.00). Analysis of total soluble solids (0 Brix), titratable acidity (% citric acid) and anthocyanins (mg/100g) in this order gave the following FDMEE (5.1+0.00, 15.35+0.2, 968.53+0.26); FDMCE (5.5+0.00, 18.41+0.16, 1217.13); FDMWE (4.8 + 0.00, 13.93 + 0.14, 882.51 + 0.44). These values were significantly different from their non-encapsulated equivalents (p<0.05). Sensory scores for jam containing microencapsulated extract compared favourably with the non-encapsulated inclusive samples. Freeze dried microencapsulated anthocyanins in native corn starch is colour stable and valuable in the production of acceptable jam.
... Pullulan is a linear polysaccharide consisting of maltotriose units interconnected by single (a1!6) glycosidic linkages (Table 2). This alternating pattern is responsible for the slow digestibility of pullulan in humans (Wolf et al. 2003). It is a white soluble polymer without taste and odor (Khan, Park, and Kwon 2007). ...
Article
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The glycemic carbohydrates we consume are currently viewed in an unfavorable light in both the consumer and medical research worlds. In significant part, these carbohydrates, mainly starch and sucrose, are looked upon negatively due to their rapid and abrupt glucose delivery to the body which causes a high glycemic response. However, dietary carbohydrates which are digested and release glucose in a slow manner are recognized as providing health benefits. Slow digestion of glycemic carbohydrates can be caused by several factors, including food matrix effect which impedes α-amylase access to substrate, or partial inhibition by plant secondary metabolites such as phenolic compounds. Differences in digestion rate of these carbohydrates may also be due to their specific structures (e.g. variations in degree of branching and/or glycosidic linkages present). In recent years, much has been learned about the synthesis and digestion kinetics of novel α-glucans (i.e. small oligosaccharides or larger polysaccharides based on glucose units linked in different positions by α-bonds). It is the synthesis and digestion of such structures that is the subject of this review.
... It can be used for the preparation of maltotriose syrup (Singh, Saini, & Kennedy, 2010a;Singh, Saini, & Kennedy, 2010b;Singh, Saini, & Kennedy, 2011). Human enzymes can slowly digest pullulan and gradually convert it into glucose, so it can be incorporated in dietetic snack foods designed for diabetic patients who have impaired glucose tolerance (Wolf, 2005). Pullulan has low viscosity (Tsujisaka & Mitsuhashi, 1993) and solution making properties (Buliga & Brant, 1987;Kato, Okamoto, Tokuya, & Takahashi, 1982;Kawahara, Ohta, Miyamoto, & Nakamura, 1984;Nishinari et al., 1991). ...
Article
Pullulan is a microbial exopolysaccharide produced from Aureobasidium pullulans by submerged fermentation of a medium supplemented with carbon, nitrogen and other essential nutrients. These nutrients are expensive which increase the cost of pullulan production. The requirement of alternative cost-effective substrates for pullulan production is a prerequisite. Agro-based industries generate a large volume of solid/liquid waste and its accumulation generates a severe environmental impact. These wastes are composed of carbohydrates, proteins and other constituents, and can be used as substrates for the development of low-cost processes for the production of various microbial products. This could be a good environmental friendly waste management system. Pullulan production from agro-industrial wastes can be carried out by both submerged and solid-state fermentation by A. pullulans. Owing to its unique properties, pullulan has wide applications in many food-based industries. This review highlights pullulan production from agro-industrial wastes and potential applications of pullulan in various food industries.
... Lentinus edodes [61][62][63] Glomerellan Glomerella cingulata [64] Pestalotan Pestalotia sp. [65] Schizophyllan Schizophyllum commune [66][67][68][69] Scleroglucan Sclerotium glucanicum [56,70] Grifolan Grifola frondosa [71,72] Pullulan Aureobasidium pullulans [73][74][75][76] Pachyman Poria cocos [77][78][79] Pleuran Pleurotus ostreatus [80,82] Chitin Cunninghamella elegans [32] Mucor rouxii [83] Rhizopus oryzae [84] Agaricus bisporus [85] Ganoderma lucidum [86] Chitosan Aspergillus niger [16] Candida albicans [16] Gongronella butleri [29] Lentinus edodes [16] Mucor rouxii [40,43,87] Penicillium sp. [18] Rhizopus oryzae [16,33,34] CGC and/or ChCG Aspergillus niger [10,88,89] Aspergillus fumigatus [90] Armillariella mellea [91,92] Morchella esculenta [92] Pichia pastoris [12] Mucor rouxii [88] Saccharomyces cerevisiae [93] Schizophyllum commune [94] Gongronella butleri [95] Pleurotus ostreatus [96] Agaricus bisporus [97] Mannans Galactomannan Aspergillus fumigatus [19] Acidic galactomannan Lecanicillium muscarium [21] Xylomannan Auricularia polytricha [28] Polymers Sources References ...
Article
Purified chitin–glucan complex (CGC pure) was extracted from Komagataella pastoris biomass using a hot alkaline treatment, followed by neutralization and repeated washing with deionized water. The co-polymer thus obtained had a-glucan:chitin molar ratio of 75:25 and low protein and inorganic salts contents (3.0 and 0.9 wt%, respectively). CGC pure had an average molecular weight of 4.9 × 10 5 Da with a polydispersity index of 1.7, and a crystallinity index of 50%. Solid-state NMR provided structural insight at the co-polymer. X-ray diffraction suggests that CGC pure has-chitin in its structure. CGC pure presented an endothermic decomposition peak at 315 • C, assigned to the degradation of the saccharide structures. This study revealed that K. pastoris CGC has properties similar to other chitinous biopolymers and may represent an attractive alternative to crustacean chitin derived-products, being a reliable raw material for the development of new/improved pharmaceutical, cosmetic or food products.
... Starch, the thickener traditionally used in lokum production is a natural polymer, the monomeric unit of which is glucose. Starch in its cooked form is readily digestible whereas pullulan has been described as a type of dietary fiber slowly digested in the human gut (Chaen 2010;Wolf et al. 2003) and hence it is used as a low-calorie food additive to provide bulk and texture. Pullulan is a non-ionic exopolysaccharide of fungal origin (Prajapati et al. 2013) that has received GRAS status (EFSA 2007). ...
... This 70% reduction was expected knowing that the Resistant Dextrin control was composed of 70 resistant and 30% digestible dextrin [18] The fact that Dextran 60, which is fully digestible, reduces 2h-iAUC almost as much as this control is consistent with results obtained with pullulan, another fully digestible polysaccharide with a structure featuring both α-1,4 and α-1,6 glycosidic bonds. For 50 g pullulan, a reduction of 50% in 3h-iAUC vs. 50 g maltodextrin has been reported for an average molecular weight > 100 kDa, equivalent to DP > 555 [19]. For lower molecular weight (6300 Da, equivalent to DP 35), 50 g pullulan did not reduce the glucose response, confirming our finding that, in conjunction with the structure, molecular weight plays an important role [20]. ...
Article
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The complexity of the carbohydrate structure is associated with post-prandial glucose response and diverse health benefits. The aim of this study was to determine whether, thanks to the usage of minimally invasive glucose monitors, it was possible to evaluate, in a decentralized study setup, the post-prandial glycemic response (PPGR) of α-glucans differing systematically in their degree of polymerization (DP 3 vs. DP 60) and in their linkage structure (dextrin vs. dextran). Ten healthy subjects completed a double-blind, randomized, decentralized crossover trial, testing at home, in real life conditions, four self-prepared test beverages consisting of 25 g α-glucan dissolved in 300 mL water. The incremental area under the curve of the 120 min PPGR (2h-iAUC) was the highest for Dextrin DP 3 (163 ± 27 mmol/L*min), followed by Dextrin DP 60 (−25%, p = 0.208), Dextran DP 60 (−59%, p = 0.002), and non-fully caloric Resistant Dextrin (−68%, p = 0.002). These results show that a fully decentralized crossover study can be successfully used to assess the influence of both polymerization and structure of α-glucans on PPGR.
... Pullulan is an extracellular polysaccharide excreted by the filamentous fungus Aureobasidium pullulans, consisting of maltotriose units (such as panose) linked through α (1→6) glycosidic bonds. Pullulan is partly digested and absorbed in the small intestine of humans, and partly fermented in the large intestine (Wolf et al., 2003). Fermentation of pullulan has been studied using human faecal bacteria and the increased production of SCFAs was measured (Spears et al., 2007). ...
Article
Polysaccharides are abundant biomolecules in nature presenting important roles in a wide variety of living systems processes. Considering the structural and biological functions of polysaccharides, their properties have raised interest for tissue engineering. Herein, we described the latest advances in cardiac tissue engineering mediated by polysaccharides. We reviewed the data already obtained in vitro and in vivo in this field with several types of polysaccharides. Cardiac injection, intramyocardial in situ polymerization strategies, and scaffold-based approaches involving polysaccharides for heart tissue engineering are thus discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.
Conference Paper
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The aim of the study was preparing the fast dissolving oral thin film(edible film) formulation that contains tramadol and base material, including Pullulan as film forming agent. Dissolution test of strips were performed by using Agilent UV Spectrophotometer and Pharmatec dissolution system with USP 5 paddle over disk method and samples were taken at time intervals from 0 to 30 min. Tramadol concentrations were assayed spectrophotometrically at 271 nm by UV –Visible spectrophotometer. The dissolution test showed that approximately % 60 of tramadol was dissolved within 2 min, also in 4 min reach up to % 90. The potential of this drug delivery approach was assessed in vivo using rats. The presence of tramadol in plasma following delivery by oral mucosa or gastric gavage was evaluated analgesic effect using Hot plate sensitivity test to measure sensitivity of the rat to the pain stimulus after administration of oral dissolvable film or solution. We measured the rat’s response to pain stimulus before drug or saline administration and again 10,20,30,40,60 min after agent administration. Each rat received a control of 0.5 ml 0.9% saline or placebo strip and one doses of tramadol by oral mucosa or gastric gavage. The doses of tramadol hydrochloride investigated were 24 and 28 mg kg−1.
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In daily diet, Whey protein (WP) is often coexisted with various Food functional ingredients (FFI) such as proteins, polyphenols, polysaccharides and vitamins, which inevitably affect or interact with each other. Generally speaking, they may be interact by two different mechanisms: non-covalent and covalent interactions, of which the former is more common. We reviewed the non-covalent interactions between WP and various FFI, explained the effect of each WP-FFI interaction, and provided possible applications of WP-FFI complex in the food industry. The biological activity, physical and chemical stability of FFI, and the structure and functionalities of WP were enhanced through the non-covalent interactions. The development of non-covalent interactions between WP and FFI provides opportunities for the design of new ingredients and biopolymer complex, which can be applied in different fields. Future research will further focus on the influence of external or environmental factors in the food system and processing methods on interactions.
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The objective of this study was to determine the effects of continuous moderate exercise on the differential and total count leukocyte, serum glucose concentration and lipid levels of rats supplemented and not supplemented with carbohydrate solution. To this purpose, thirty-five male Wistar rats were divided into four groups: sedentary non-supplemented (n = 10) and supplemented (n = 8), trained in continuous moderate aerobic exercise non-supplemented (n = 9) and supplemented (n = 8). The training of continuous swimming was developed during six week with 3% body weight overload. For five days the animals were supplemented with 0.48 g.kg-1 maltodextrin daily dose dissolved in water or pure water. Moderate exercise caused a significant decrease in blood glucose (p < 0.001) and in the number of blood lymphocytes (p < 0.01). Additionally, the maltodextrin significantly increased the number of lymphocytes of trained animals (p < 0.03). There was no effect of training and maltodextrin on the lipid profile. The results allowed to conclude that with six weeks of training it was possible to cause a drop in the number of lymphocytes and in the concentration of serum glucose, but with five days of supplementation the decline in the lymphocyte count was attenuated without, however, cause elevations in the lipid profile.
Article
The objective of this study was to compare two in vivo methods using pigs and roosters and an in vitro method for determining the caloric value of four fiber sources [i.e., two resistant starches (RS 60 and RS 75), soluble corn fiber (SCF 70), and pullulan]. Metabolizable energy (ME) in pigs and true metabolizable energy (TMEn) in roosters were determined by using 72 barrows and 24 roosters, respectively. A two-step in-vitro procedure was used to quantify monosaccharides released. Results of the two in vivo experiments corresponded well with RS 75 having the least caloric value (7.55 MJ/kg in pigs; 6.19 MJ/kg in roosters) and pullulan having the greatest caloric value (12.21 MJ/kg in pigs; 13.94 MJ/kg in roosters). The caloric values for all the fiber ingredients were less (P < 0.05) than in MD both in pigs and in roosters. Despite some limitations, results of the in vitro procedure corresponded well with the in vivo experiments where the concentration of glucose hydrolyzed from RS 60, RS 75, and SCF 70, but not pullulan, was less (P < 0.05) than the concentration of glucose hydrolyzed from MD. However, the greatest accuracy was obtained in the in vivo experiments.
Article
Pullulan is a water-soluble extracelluler polysaccharide produced aerobically by fungus Aureobasidium pullulans and some other species. Current work focused on developing an A. pullulans strain with enhanced pullulan productivity and raw material utilization ratio using a new method for genome shuffling of A. pullulans N3.387. After the third cycle of the protoplast fusion, a mutant, designated as F3-2, producing 179.7% (20.7g/L) more pullulan than the wild-type strain was obtained. Furthermore, the raw material utilization ratio of F3-2 was determined as 97.9%, which was 29.0% higher than the wild-type strain. Genetic stability analysis of F3-2 showed that ranges of the pullulan production and the raw material utilization ratio of the generation were 0.13g/L and 1.93%, respectively, suggesting that F3-2 was genetically stable. Elucidation of this new genome shuffling process is also interesting for enhancing production of extracellular polysaccharide in both A. pullulans and other fungus.
Article
The objective of this study was to evaluate the glycemic, insulinemic, and breath hydrogen responses of healthy adult humans to low–molecular weight pullulan (molecular weight = 6300). Subjects (n = 34) consumed 50 g of maltodextrin or low–molecular weight pullulan in a randomized, double-masked, crossover design. Plasma glucose and serum insulin responses were determined over 180 minutes, and breath hydrogen response was determined for 8 hours. Low–molecular weight pullulan did not improve glucose response, but a reduction (P < .05) in serum insulin at 30, 60, and 90 minutes was noted. Peak insulin and area under the curve were reduced (P < .05) by 23% and 20%, respectively. Breath hydrogen increased (P < .05) at 4, 5, 6, 7, and 8 hours. Although low–molecular weight pullulan does not impact glycemia per se, it may reduce insulin response, resulting in decreased insulin concentrations in healthy adult humans.
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Mucosal sites serve as the main portal for the entry of pathogens and thus immunization through mucosal routes can greatly improve the immunity. Researchers are continuously exploring the vaccination strategies to engender protective mucosal immune responses. Unearthing of mucosal adjuvants, that are safe and effective, is enhancing the magnitude and quality of the protective immune response. Use of nanotechnology based polymeric nanocarrier systems which encapsulate vaccine components for protection of sensitive payload, incorporate mucosal adjuvants to maximize the immune responses and target the mucosal immune system is key strategy to improve the effectiveness of mucosal vaccines. These advances promise to accelerate the development and testing of new mucosal vaccines against many human diseases. This review focuses the need for the development of nanocarrier based mucosal vaccines with emphases on the polymeric nanoparticles, their clinical status and future perspectives. This review focuses the need and new insights for the development of nanoarchitectures governed mucosal vaccination with emphases on the various polymeric nanoparticles, their clinical status and future perspectives. Copyright © 2014. Published by Elsevier Inc.
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Glucose is the principal biological fuel for the body, and it has been classified into rapidly available glucose (RAG) and slowly available glucose (SAG) based on glycemic carbohydrate digestion rate that is related to human health. This chapter first reviews the concept of glycemic index (GI), and the digestion and nutritional classification of glycemic carbohydrates. The structural properties, slow digestion mechanism, and the biological functions of slowly digestible carbohydrates (SDC), mainly slowly digestible starch (SDS), are then discussed. Finally, potential formulation and testing of low-GI foods, using SDCs to control the glucose delivery, are described for the purpose of improving human health.
Article
In this research, pullulan was incorporated in protein-based encapsulation matrix in order to assess its cryoprotective effect on the viability of freeze-dried (FD) probiotic Lactobacillus acidophilus NRRL-B 4495. This study demonstrated that pullulan in encapsulation matrix resulted in a 90.4% survival rate as compared to 88.1% for whey protein (WPI) encapsulated cells. The protective effects of pullulan on the survival of FD-encapsulated cells in gastrointestinal conditions were compared. FD WPI-pullulan capsules retained higher survived cell numbers (7.10 log CFU/g) than those of FD WPI capsules (6.03 log CFU/g) after simulated gastric juice exposure. Additionally, use of pullulan resulted in an increased viability after bile exposure. FD-free bacteria exhibited 2.18 log CFU/g reduction, while FD WPI and FD WPI-pullulan encapsulated bacteria showed 0.95 and 0.49 log CFU/g reduction after 24 h exposure to bile solution, respectively. Morphology of the FD microcapsules was visualized by scanning electron microscopy.
Chapter
A classification of starch into rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) has been used to specify the nutritional quality of starch. SDS is the most elusive fraction of the three, perhaps due to its somewhat transient nature, and it is certainly less studied than RS. This chapter covers the current understanding of SDS, including its concept and potential health benefits. The chapter discusses the starch digestion process, structure and mechanism of SDS and approaches to making SDS. Currently, there are very few approaches to make commercially viable SDS. Further understanding of consequences of SDS that might include energy balance, metabolic diseases, cognitive and physical performance and satiety, are needed. New technologies also must be identified to make robust and more defined SDS materials for use in the food industry.
Article
In this research, whey protein/pullulan (WP/pullulan) microcapsules were developed in order to assess its protective effect on the viability of Lactobacillus acidophilus NRRL-B 4495 under in vitro gastrointestinal conditions. Results demonstrated that WP/pullulan microencapsulated cells exhibited significantly (p ≤ 0.05) higher resistance to simulated gastric acid and bile salt. Pullulan incorporation into protein wall matrix resulted in improved survival as compared to free cells after 3 h incubation in simulated gastric solution. Moreover WP/pullulan microcapsules were found to release over 70% of encapsulated L. acidophilus NRRL-B 4495 cells within 1 h. The effect of encapsulation during refrigerated storage was also studied. Free bacteria exhibited 3.96 log reduction while, WP/pullulan encapsulated bacteria showed 1.64 log reduction after 4 weeks of storage. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
Article
The objective of this work was to produce the bioengineered α-D-glucan from Leuconostoc citreum SK24.002 and study its molecular structure and prebiotics properties. The connectivities and substitutions of α-D-glucan were measured using 2D NMR and the chain structure of the repeating unit was deduced. During in vitro fecal fermentation, a strong increase in bacterial population was observed and the largest changes took place during the first 24 h of incubation. A decrease pH (approximately 2.0) was also observed for the fermentation from 0 h to 48 h compared to the blank (pH 6.8-6.6). Total short-chain fatty acid (SCFA) increased during batch fecal fermentation in the presence of α-D-glucan and it reached the maximum level of 30.01 mM after 48 h of fermentation. The lowest gas production and highest butyric acid production at 48 h of incubation was recorded with α-D-glucan as compared with dextran or pullulan. Moreover, human fecal microbiota on α-D-glucan produced more butyric acid between 24 and 48 h than other test carbohydrates. These results suggest that α-D-glucan would be a good candidate slowly fermentable fiber and may have a positive effect for the gut microbiota homeostasis.
Article
Nanoparticulate drug delivery systems seem to be a viable and promising strategy for the biopharmaceutical industry. In particular of interest are polymeric nanoparticles have attracted the interest of many research groups and have been utilized in an increasing number of fields during the last decades. They have been used frequently as drug delivery vehicles due to their grand bioavailability, better encapsulation, controlled release and less toxic properties. Various nanoparticulate systems, types of polymers used, fate of the polymeric nanoparticles in vivo, control release and improvement of therapeutic value of nanoencapsulated drugs are highlighted in the current review.
Chapter
IntroductionRaw materialsProductionFunctional propertiesFood applicationsFuture developments
Chapter
A classification of starch into rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) has been used to specify the nutritional quality of starch. This chapter covers the current understanding of SDS, including its concept and potential health benefits, the starch digestion process, structure and mechanism of SDS and approaches to making SDS. SDS is associated with positive health outcomes that may include moderated postprandial glycaemia, circulating free fatty acids and oxidative stress. Moreover, high levels of SDS-containing legumes are considered beneficial to diabetic control, and it has been shown that a bedtime meal containing SDS (corn starch) improved glucose tolerance for the second morning meal. Currently, there are very few approaches to make commercially viable SDS. Practically, at this time strategies can be reduced to two areas: starch molecular structures that reduce digestion rate; and food matrices with slow starch digestion.
Chapter
There is a significant effort to use nanomaterials (NMs) in a range of applications in recent years. Their use in almost all applications requires tuning one of the parameters such as size and shape influencing their extraordinary properties. The surface chemistry of NMs also plays a critical role for their effective use. The successful surface modification allows the preparation of more functional and advance materials benefiting from their unique properties of these novel materials. There is an enormous diversity not only in NMs but also molecules and molecular structures available for surface modifications. In this chapter, NM surface modification strategies, which can be used for development of advance materials, are discussed by emphasizing NMs surface chemistry and chemical nature of modifiers. In addition, modification strategies using biocompatible polymers and modifiers with biological origin such as carbohydrates, oligonucleotides, and peptides to generate advance materials are included in the discussion.
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Soluble dietary fibre (DF), including β-glucan, guar gum, psyllium and alginate, reduce the absorption rate of glucose after the consumption of a high carbohydrate load through its beneficial viscosity properties. The addition of DF to high carbohydrate liquids and foods has shown significant reductions in postprandial glucose absorption albeit palatability issues at the concentrations required to see the beneficial effect have limited their applications as a functional food ingredient. Changes in the physiochemical properties of the DFs following food processing negatively impacts on DF viscosity and ultimately reduces efficacy. Research is focusing on exploring processing procedures that minimize disruption to these physicochemical properties such as changes to temperature , molecular weight and contact times. Furthermore, the development of novel composite DF blends that draw on individual characteristics is a novel method of utilizing DF as a functional food ingredient for its glycemic lowering ability.
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The aim of the present study was to investigate the prevalence of tetracycline resistance genes among isolated S. aureus from healthcare associated surgical site infections. The present study included 350 clinical samples from healthcare associated surgical site infections. Identified S. aureus strains were subjected to antimicrobial susceptibility testing, detection of methicillin resistance by cefoxitin disc and molecular study of mecA and tet genes that were carried out by polymerase chain reaction and multiplex polymerase chain reaction, respectively. There were high resistance rates of isolated S. aureus to gentamicin (71.2%), kanamycin (66.5%) and ceftazidime (41.8%). Resistances to tetracycline, doxycycline and minocycline were 60.6%, 56.5% and 45.3%, respectively. In the comparison between MRSA and MSSA as regards antibiotics resistance, there was a significant increase in resistance to tetracycline, doxycycline, minocycline (P=0.0001) and erythromycin (P=0.01) among MRSA strains compared to MSSA. The tetracycline resistant genes detected were tetK (92.3%) and tetM (25.2%). Combined genes were detected in 22.3% of S. aureus. None of tetracycline isolates had tetL or tetO gene. There was significant higher frequency of telK, tetM and combined genes among MRSA compared to MSSA (P=0.0001). The present study highlights the prevalence of multiple antibiotics resistance among clinical isolates of S. aureus associated with healthcare associated infections. The resistance increases among methicillin resistant S. aureus. The resistance to tetracycline, minocycline and doxycycline were common. The common genetic basis of the resistance to tetracycline was the tetK and tetM genes.
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Nowadays, the growing interest of using of biopolymer to replace petroleum based material asare increasing tremendously. Microbial biopolymers are usually water-soluble gum which have innovative and unique physical characteristics.Pullulan is a biodegradable and water soluble exopolysaccharide synthesized by the yeast-like fungus Aureobasidium pullulans. This polymorphic fungus is well known as producer of the polysaccharide, pullulan and other by-products such as oil, organic acids, pigment, and others. Pullulan has extensive applications in pharmaceutical, cosmetic, biomedical, and food industries because of its advantageous chemical and physical properties. Pullulan's structure is coexistence of á-(1, 4) and á-(1, 6) linkages which is nontoxic, tasteless and non-mutagenic. Some of its excellent properties are low viscosity, non-toxicity, slow digestibility, high plasticity, and excellent film-forming capabilities. Although pullulan shows great potential in several industries, its high production cost is a major drawback. Therefore, cheaper and accessible substrate which can minimize the production cost is needed. This review highlights the potential use of agro-industrial waste as an alternative source feedstock for pullulan production and its biosynthesis, chemical structure, production process and applications.
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Fungal biopolymers have gained considerable attention from the scientific community for various applications due to their biological and physicochemical properties. The wide applications in several areas, especially in the food industry as a bioemulsifier and in the agricultural area as a biosurfactant, have expanded the knowledge on the production of fungal biopolymers to keep up with developments on this subject area. Recent scientific studies have disclosed novel routes, optimized parameters, increased yields, and other related approaches in order to produce and apply fungal bioemulsifiers and biosurfactants. However, there is a need to gather important information in order to provide a way forward. Therefore, this review presents an overview of properties, applications, and perspectives for encouraging further projects and investments in the near future by most categories of investors. The selection of culture media, the definition of cultivation parameters, extraction, recovery, and purification are the initial steps to indicate the conditions for scale-up. Indeed, scale-up is still one of the challenges in this biotechnological field, which could be solved by expanding the tests and operational productions in both pilot and industrial plants.
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Fibre has been shown to exert a number of benefits on gastrointestinal (GI) health, yet its intake is low. Addition of novel fibres to food products may increase fibre intake and improve gut health. The objective of the present study was to evaluate the influence of three novel fibres on GI outcomes in healthy human subjects. A total of twenty healthy participants (ten men and ten women) with normal BMI (23 (sem 2) kg/m2) participated in the present randomised, double-blind, cross-over study with five treatment periods. Participants consumed a maltodextrin control or 20-25 g/d fibre from soluble maize fibre (SCF) or resistant starch (RS), alone or in combination with pullulan (SCF+P and RS+P). The treatment periods were 7 d with a 3-week washout between the periods. Stool samples were collected on day 7 of each period, and GI tolerance was assessed via a questionnaire on days 1 and 6. There were no treatment differences in stool weight or consistency. SCF significantly reduced stool pH and increased total SCFA production compared with RS and control. RS+P significantly increased the percentage of butyrate compared with all the other treatments. Overall, GI symptoms were minimal. SCF+P led to the highest GI score on day 1, while RS+P had the highest score on day 6. Both SCF treatments caused a significant shift in the gut microbial community. These functional fibres are generally well tolerated, have minimal effects on laxation and may lead to beneficial changes in SCFA production in healthy adults.
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Context Recent reports show that obesity and diabetes have increased in the United States in the past decade.Objective To estimate the prevalence of obesity, diabetes, and use of weight control strategies among US adults in 2000.Design, Setting, and Participants The Behavioral Risk Factor Surveillance System, a random-digit telephone survey conducted in all states in 2000, with 184 450 adults aged 18 years or older.Main Outcome Measures Body mass index (BMI), calculated from self-reported weight and height; self-reported diabetes; prevalence of weight loss or maintenance attempts; and weight control strategies used.Results In 2000, the prevalence of obesity (BMI ≥30 kg/m2) was 19.8%, the prevalence of diabetes was 7.3%, and the prevalence of both combined was 2.9%. Mississippi had the highest rates of obesity (24.3%) and of diabetes (8.8%); Colorado had the lowest rate of obesity (13.8%); and Alaska had the lowest rate of diabetes (4.4%). Twenty-seven percent of US adults did not engage in any physical activity, and another 28.2% were not regularly active. Only 24.4% of US adults consumed fruits and vegetables 5 or more times daily. Among obese participants who had had a routine checkup during the past year, 42.8% had been advised by a health care professional to lose weight. Among participants trying to lose or maintain weight, 17.5% were following recommendations to eat fewer calories and increase physical activity to more than 150 min/wk.Conclusions The prevalence of obesity and diabetes continues to increase among US adults. Interventions are needed to improve physical activity and diet in communities nationwide.
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For nutritional purposes, starch in foods may be classified into rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS). RS may be further divided into three categories according to the reason for resistance to digestion. A method is reported for the measurement of total starch, RDS, SDS, RS and three RS fractions in starchy foods, using controlled enzymic hydrolysis with pancreatin and amyloglucosidase. The released glucose is measured by colorimetry, using a glucose oxidase kit. Values for RDS and SDS in foods obtained by the method reflect the rate of starch digestion in vivo. Values for RS are similar to the amounts of starch escaping digestion in the small intestine of ileostomates, and are a guide to the amounts of starch likely to enter the colon for fermentation. Results are given for a number of starchy foods.
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The extent to which monitoring breath hydrogen excretion provides information concerning the entry of the residues of a solid test meal into the colon was investigated in 89 normal subjects, and 11 patients with the irritable bowel syndrome. The profile of breath hydrogen concentration showed an early peak, that occurred soon after ingesting the test meal in 89% subjects. This was followed by a later more prolonged rise in breath hydrogen concentration. The early peak occurred well before a radioactive marker, incorporated in the test meal, reached the caecum and the data suggest it was predominantly caused by the emptying of the remnants of the previous meal from the ileum into the colon. This hypothesis was supported by direct measurements of the rate of delivery of ileostomy effluent in 12 subjects with terminal ileostomies. Fermentation of carbohydrate in the mouth may, however, contribute to the initial peak, but this contribution may be avoided by collecting gas samples from the nares. The secondary rise in breath hydrogen excretion was closely correlated with the arrival of the radioactive marker in the caecum (r = 0.91), p less than 0.001), though the time, at which the secondary peak of breath hydrogen excretion occurred was poorly correlated with the time that all the radioactive test meal had entered the colon. When lactulose was infused directly into the colon, as little as 0.5 g produced a discernible hydrogen response, which occurred within two minutes of the infusion. Increasing the rate of colonic infusion of a 50 ml solution of 10% lactulose from 0.02 to 0.15 g/min in five subjects significantly increased the breath hydrogen concentration. At infusion rates below 0.075 g lactulose/minute, the peak breath hydrogen response preceded the end ot the infusion, while at higher rates of infusion, the peak hydrogen response occurred after the end of the infusion. Although these results confirmed that monitoring breath hydrogen concentration usefully signalled the time taken for a meal containing unabsorbed carbohydrate to reach the colon, it did not reliably indicate the time when all of the meal had entered the colon. Finally, the use of the maximum increase in breath hydrogen concentration as an index of the degree of carbohydrate malabsorption assumes uniform rates of entry into the colon.
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To test the hypothesis that complete elimination of lactose is not necessary to ensure tolerance by lactose maldigesters. Double-blind, randomized protocol in which challenge doses of 0, 2, 6, 12, and 20 g lactose in water were fed to subjects after a 12-hour fast. 13 healthy, free-living adults who were lactose maldigesters. Breath hydrogen production (a measure of maldigestion) and symptom response to each challenge dose. Analysis of variance was done to determine overall differences in mean hydrogen gas production (peak and sum of hours 1 through 8). Friedman's test was used to determine overall differences in the mean ranks for each symptom. Fisher's least significant difference test was used for multiple comparisons for hydrogen and symptom and data. Hydrogen production after consumption of the 0- and 2-g lactose doses was not significantly different. Hydrogen production increased with the 6-g dose. Intensity of abdominal pain increased when the dose of lactose was 12 g. Episodes of flatulence did not increase until the dose reached 20 g. No significant differences in the occurrence of diarrhea were observed after the five treatments. No significant increase in breath hydrogen production or intolerance symptoms occurred after consumption of a 2-g dose of lactose. Up to 6 g was tolerated, even though maldigestion could be measured at the 6-g dose. Thus, lactose maldigesters may be able to tolerate foods containing 6 g lactose or less per serving, such as hard cheeses and small servings (120 mL or less) of milk.
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The goal of treatment of type I glycogen storage disease (GSD-I) is to prevent hypoglycemia and its biochemical consequences. In seven patients with GSD-I with a mean age of 19.5 y (range: 18.8-21.7 y), we compared the biochemical effects of isoenergetic amounts of uncooked cornstarch (UCS; 1.76 +/- 0.41 g/kg) given in random order on consecutive nights either as a single dose at 2100 (time 0) or as equally divided doses at 2100 and 0200. Over the 10-h period of observation there were significant regimen-by-time interactions for plasma glucose, serum insulin, and blood lactate concentrations. Mean time-averaged plasma glucose (5.8 +/- 0.5 compared with 4.9 +/- 0.9 mmol/L) and serum insulin (244 +/- 93 compared with 151 +/- 57 pmol/L) concentrations from 0 to 360 min were significantly higher after the single dose; blood lactate and serum fatty acid concentrations were not significantly different. At 360 min, mean plasma glucose (4.8 +/- 1.2 compared with 4.7 +/- 1.6 mmol/L) and serum insulin (138 +/- 76 compared with 136 +/- 116 pmol/L) concentrations were virtually identical. After a single dose, plasma glucose concentrations were > or = 3.9 mmol/L for 7 h in five of seven subjects; three subjects were treated for hypoglycemia after 7-9.5 h. With divided doses, plasma glucose concentrations were > or = 3.9 mmol/L for 9 h in six of seven subjects; hypoglycemia occurred at 6 h in one subject. A single dose (1.76 +/- 0.41 g/kg) of UCS at bedtime maintains plasma glucose concentrations > or = 3.9 mmol/L for > or = 7 h in most young adults with GSD-I.
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Pullulan is a natural polysaccharide with a linear structure comprising repeating alpha;-l,6-linked maltotriose molecules which elaborated by a black yeast, Aureobasidium pullulans. Pullulan, a tasteless, oderless, and edible white fine powder, is a natural glucan as are amylose, dextran, and cellulose, but dissolves readily in cold water to form a viscous, non-gelling, aqueous solution. The features of pullulan, superior to those of other polysaccharides, provide pullulan as an excellent adhesive, binder, thickener, viscosity stabilizer and coating agent for food application. Pullulan films prepared with aqueous solution are edible and oxygen impermeable. Besides the food industry, pullulan is widely used in pharmaceutical, biotechnical and other industries. © 1984, The Society of Synthetic Organic Chemistry, Japan. All rights reserved.
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Wistar系幼若雄白ネズミ (体重約50g) に5, 10, 20, 40%にプルランを含む飼料ならびに20, 40%にセルロースを含む飼料を投与して, 白ネズミの成長曲線ならびに各臓器に対する影響, さらに小腸粘膜の糖質分解酵素におよぼす影響などを観察した。1) プルランを20%ならびに40%に含む飼料で飼育した場合には, 著しい成長抑制が観察された。40%セルロース投与群においても同様の成長抑制がみられた。しかしながら, 抑制の程度ならびに抑制の現われ方はプルラン投与群とセルロース投与群との間に多少の差異があった。2) 大量のプルラン (20%, 40%プルラン飼料) を長期間投与すると胃, 小腸, 盲腸, 大腸の肥大する傾向が観察された。その影響は, とくに盲腸に対して著しかった。セルロースを投与した場合には大腸に肥大が著しかった。消化管の肥大の部位と程度は, 飼料中のプルランまたはセルロース含量と飼育期間によって異なっていた。消化管以外の臓器に対してはプルランならびにセルロースの影響はほとんど観察されなかった。3) 小腸粘膜のマルターゼ, シュクラーゼ, イソマルターゼ活性は, いずれもプルランならびにセルロースの投与によって影響されなかった。プルランは試験管内において小腸粘膜に存在する酵素によって部分分解された。4) プルランを胃内に投与した場合に, 60分間でプルランのグリコシド結合の約3%が消化管内で加水分解された。この量はプルラン分子中に含まれるマルトテトロースユニットの量に一致していた。以上の結果, プルランは腸管内で二糖類または単糖類まで分解されにくく, 生体に利用されにくい多糖類と思われる。セルロースならびにプルランのような生体で利用されにくい多糖類を, 白ネズミに大量に投与すると盲腸, 大腸が肥大する。これは生体がそれらの物質になじむための一種の生理的な適応現象ではないかと考える。
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ヒト生体内における糖質の消化条件に適応する, in vitro消化試験系を確立した。この試験系により, プルランの消化性を調べたところ, 胃酸ではまったく消化されず, 唾液アミラーゼと膵液アミラーゼにより低分子化され, さらに小腸粘膜酵素では低分子化されるとともに, 少量のグルコースを生成することが明らかとなった。小腸以前の上部消化管でグルコースまで消化されて吸収されるプルランは摂取量の5%以下であると推定された。この結果はプルランが「ヒトの消化酵素で消化されない食物中の難消化性成分の総体」と定義される食物繊維にあてはまることを示唆している。また大腸内での発酵を, 糞便培養法によるin vitro試験系で再現した。その結果, プルランは大腸内ですべて発酵されることが明らかとなった。発酵により生成する短鎖脂肪酸は, 酢酸プロピオン酸, n-酪酸が多く, コハク酸, がわずかに生成した。酢酸, プロピオン酸, n-酪酸の生成量はプルラン中のグルコース1残基当りそれぞれ0.58, 0.21, 0.24であった。また炭素回収率は47.8%となった。生体におけるプルランのエネルギー評価は, 消化試験および発酵試験の結果を用いて行った。エネルギーは2.10kcal/g-プルラン (8.79kJ/g-プルラン) と計算された。しかし実際には, 糞便への短鎖脂肪酸の排泄量の増加が考えられ, プルランのエネルギーはさらに低いと推定した。
Article
To evaluate the effect of supplemental indigestible dextrin on the glycemic response to a rapidly digested starch, 30 healthy nondiabetic adult subjects were studied in a double-blind crossover design. After an overnight fast, subjects consumed a product containing either 67.5 g of corn syrup solids or the same plus 16 g of indigestible dextrin. Finger-prick capillary blood was obtained at baseline, 15, 30, 45, 60, 90, and 120 min postprandial for glucose measurement. The postprandial incremental change from baseline did not differ (P > 0.10) between treatments across all time points. Mean peak incremental change from baseline and net incremental area under the curve did not differ (P > 0.10) between treatments. Minimal effects on gastrointestinal symptoms (intensity and frequency of nausea, cramping, distention, and flatulence) were noted for both products, with no clinically significant difference between products. In conclusion, an acute challenge of 16 g supplemental indigestible dextrin did not affect the postprandial glycemic response to a rapidly digested starch and was well tolerated by fasting healthy adult subjects.
Article
A series of in vivo and in vitro experiments was conducted to determine the available energy of a bulking agent, Fibersol 2 (FS-2). Fibersol 2 is obtained by a combination of heat and enzyme treatments of cornstarch to produce a low-viscosity, low-digestible dextrin with an average molecular massweight of 2000 Da. Although the substance is of the type known in Japan as an indigestible dextrin, it also comes within the U.S. Food and Drug Administration's (FDA) definition of “maltodextrin” as found in the FDA Generally Recognized as Safe (GRAS) affirmation regulations. Chemical analysis shows FS-2 to contain glucopyranosyl units with 1,6-anhydro-β-d-glucose (levoglucosan) at some of the reducing terminals. Linkages in the molecule are randomly distributed among units consisting of α- and β-(1→4), (1→6), (1→2), and (1→3) glycosidic bonds. In vitro digestion of FS-2 with successive treatments of salivary α-amylase, a gastric juice preparation, pancreatic α-amylase, and intestinal mucosal enzymes gave 89.8% recovery of the starting material. Rats gavaged with FS-2 were found to have only a 5% increase in plasma glucose concentrations over 120 min compared to rats administered an equal amount of glucose. Approximately 38% of FS-2 administered to rats by gavage is recovered in the feces. Growth rates of rats fed FS-2 indicate less than <10% of the dextrin is contributing net metabolizable energy. FS-2 has an energy value of 2.2 kJ/g. Keywords: Dextrin; maltodextrin; bulking agent; energy and; rats
Article
Polycose, a glucose polymer produced by controlled acid enzyme hydrolysis of starch, has been proposed as an effective substitute for glucose solution in antepartum screening for glucose intolerance. The purposes of this study were to examine the glucose and hormonal responses to 50 g of glucose polymer (polycose) solution in pregnant and nonpregnant women and to compare these with the standard 50-g oral glucose challenge test. In addition, the subject's acceptance of the glucose polymer solution was evaluated. Subjects were examined after an overnight fast following a 3-day dietary preparation. There was no difference in glucose or insulin responses to glucose or polycose in either pregnant or nonpregnant women. In contrast, the gastric inhibitory polypeptide response to polycose was significantly higher than to glucose. No differences were observed in plasma pancreatic polypeptide responses to glucose and polycose. In the pregnant subjects, even though the plasma insulin response to carbohydrate challenge was higher than in the nonpregnant subjects, gastric inhibitory polypeptide levels were significantly lower. Patient satisfaction was similar with both carbohydrate solutions. These data suggest that polycose can be used as a substitute for glucose in antepartum testing, although the differences in the hormonal responses should be recognized. Further studies in a subject population with carbohydrate intolerance will be required before polycose use can be recommended in abnormal states.
Article
We developed an in vitro assay system that mimics the physiological conditions for starch digestion. In this system all undigested starch was termed resistant starch (RS). The richest sources of RS were firm bananas and roasted chickpeas. Different food-processing techniques produced different amounts of RS. RS in uncooked oats (0.161 g/g dry wt) and firm bananas (0.247 g/g dry wt) was reduced by cooking to 0.028 and 0.032 g/g dry wt, respectively. Cooling boiled potato overnight at 4 degrees C produced a 2.8-fold increase in the amounts of RS. Whole rice contained more RS than did ground rice whereas grinding did not affect amounts of RS in roasted chickpeas. Amounts of RS in food decreased with increased chewing, indicating that chewing can also affect the amount of starch escaping digestion. This assay may be useful in predicting which foods and processing techniques result in high amounts of starch escaping digestion in the small intestine.
Article
There is controversy regarding the clinical utility of classifying foods according to their glycemic responses by using the glycemic index (GI). Part of the controversy is due to methodologic variables that can markedly affect the interpretation of glycemic responses and the GI values obtained. Recent studies support the clinical utility of the GI. Within limits determined by the expected GI difference and by the day-to-day variation of glycemic responses, the GI predicts the ranking of the glycemic potential of different meals in individual subjects. In long-term trials, low-GI diets result in modest improvements in overall blood glucose control in patients with insulin-dependent and non-insulin-dependent diabetes. Of perhaps greater therapeutic importance is the ability of low-GI diets to reduce insulin secretion and lower blood lipid concentrations in patients with hypertriglyceridemia.
Article
There has been much interest in the use of the glycemic index (GI). A recent study reporting plasma glucose responses to mixed meals containing fat and protein concluded that the results were totally disparate from what would have been expected from published GI values of the foods fed. However, this conclusion was based upon an inappropriate assessment of the data using absolute rather than incremental blood glucose response areas. The present report demonstrates how data may be analyzed to make use of the GI values of individual foods to predict the GI of mixed meals (r = 0.987; p less than 0.02). It is concluded that the GI concept applies well to mixed meals containing fat and protein.
Article
This study was designed to determine whether the rate of hydrolysis of different starches by pancreatic amylase in vitro was proportional to the postprandial glucose and insulin response to those starches after oral ingestion. Lean young men consumed four test meals of rice containing 75 g starch: white rice, unpolished (brown) rice, ground white rice, and ground brown rice. Postprandial glucose and insulin responses were measured over 4 h and showed the following pattern: ground white rice congruent to ground brown rice greater than white rice greater than brown rice. The maximum increases in blood glucose after the four meals were brown rice 0.9 mM, white rice 1.5 mM, ground brown rice 3.3 mM, and ground white rice 3.6 mM. Samples of the cooked rices were incubated in vitro with pancreatic amylase for 30 min and the percentage starch hydrolysis determine. The relative rates of starch hydrolysis correlated very closely with the peak glucose responses: brown rice 17.6%, white rice 30.8%, ground brown rice 68.2% and ground white rice 71.8%. These results indicated that the rate of intestinal hydrolysis of starch is an extremely important determinant of the metabolic responses to a particular starch. The rate of starch hydrolysis can be determine simply by an in vitro method and should assist the design of diets for the treatment of diabetes.
Article
Type I glycogen-storagen disease, an inherited absence or deficiency of glucose-6-phosphatase activity in the liver, kidney, and intestines, is associated with the accumulation of glycogen in those organs. The lack of glucose-6-phosphatase activity in the liver rapidly leads to hypoglycemia in fasting, because of the inadequate release of glucose from glucose-6-phosphate through normal glycogenolysis and gluconeogenesis. Other clinical manifestations include growth retardation, hepatomegaly, lactic acidosis, hyperuricemia, and hyperlipidemia. Most of these abnormalities have been attributed to the hypoglycemia, since treatments that maintain normal glucose concentrations correct most of the metabolic abnormalities and growth retardation. So far, the various kinds of therapy that have been used to achieve this goal have included total parenteral nutrition, portacaval shunts, and more recently, continuous nocturnal infusion of a glucose-containing solution through either a nasogastric or a gastrostomy tube and frequent day-time feedings. Practical considerations essentially preclude the use of total parenteral nutrition in long-term management. Although portacaval shunts considerably improve the patient's condition, they involve, in addition to the risks associated with surgery, the persistence of hypoglycemia. In recent years, continuous nocturnal infusion has been the choice of treatment in Type I glycogen-storage disease. Although it is generally effective, this regimen is not without danger; it requires monitoring of the nighttime infusion and avoidance of delays in daytime feedings to prevent symptomatic hypoglycemia. In addition, patients may reject the nighttime routine. To circumvent these problems, the use of cornstarch was tested to determine whether normoglycemia and adequate metabolic management could be attained with less frequent feedings and without continuous nocturnal infusion. In this paper, we report the use of uncooked cornstarch as an alternative effective therapeutic regimen for patients with Type I glycogen-storage disease.
Article
The responses of serum glucose and insulin to both cooked and raw starch were studied in 11 healthy men. Serum insulin values rose less after starch, whether raw or cooked, than after an equivalent load of glucose. That the response of insulin after cooked starch was less than after glucose suggests that viscosity of the meal was involved, whereas the greater reduction in the response of insulin to raw starch was unlikely to have had a viscosity component. Thus, both dietary fibre type and cooking can alter the response.
Article
The acute effects of different macronutrients on the secretion of glucagon-like peptide-1(7–36)amide (GLP-1(7–36)amide) and glucose-dependent insulinotropic polypeptide (GIP) were compared in healthy human subjects. Circulating levels of the two hormones were measured over a 24-h period during which subjects consumed a mixed diet. In the first study, eight subjects consumed three equicaloric (375 kcal) test meals of carbohydrate, fat and protein. Small increases in plasma GLP-1(7–36) amide were found after all meals. Levels reached a maximum 30 min after the carbohydrate and 150 min after the fat load. Ingestion of both carbohydrate and fat induced substantial rises in GIP secretion, but the protein meal had no effect. In a second study, eight subjects consumed 75 g glucose or the equivalent portion of complex carbohydrate as boiled brown rice or barley. Plasma GIP, insulin and glucose levels increased after all three meals, the largest increase being observed following glucose and the smallest following the barley meal. Plasma GLP-1(7–36)amide levels rose only following the glucose meal. In the 24-h study, plasma GLP-1(7–36)amide and GIP concentrations were increased following every meal and remained elevated throughout the day, only falling to fasting levels at night. The increases in circulating GLP-1(7–36)amide and GIP levels following carbohydrate or a mixed meal are consistent with their role as incretins. The more sustained rises observed in the daytime during the 24-h study are consistent with an anabolic role in lipid metabolism. Journal of Endocrinology (1993) 138, 159–166
Article
Although the accuracy of breath H2 testing to detect malabsorption of small (< 50 g) doses of carbohydrate has never been evaluated, studies suggest that its accuracy is limited by a high prevalence of "H2 nonproducers." The aim of this study was to determine the accuracy of H2 breath testing in the detection of malabsorption of 10 g of carbohydrate. In 55 healthy subjects, we determined the ability of breath H2 measurements to distinguish between the ingestion of 10 g of a nonabsorbable carbohydrate (lactulose) and two control meals, a nonabsorbable electrolyte solution or glucose (10 g). The conventional criterion of a 20 ppm increase in breath H2 had 100% specificity but failed to identify lactulose malabsorption in 47% and 24% of subjects at 4 and 8 hours of testing. In contrast, a breath H2 of > 6 ppm at 5 or 6 hours had near perfect specificity and sensitivity. A sum of breath H2 at 5, 6, and 7 hours of > 15 ppm yielded perfect separation between lactulose and control solutions. True "H2 nonproducers" are extremely rare. Using appropriate criteria, breath H2 testing provides a very accurate means of identifying malabsorption of low doses of carbohydrate.
Article
The aim of the present study was to validate an in vitro assay for quantifying resistant starch (RS) in foods against an in vivo model. The amount of starch escaping digestion in the small intestine of ileostomates was compared with that observed by using the in vitro assay. Subjects with ileostomies were fed five foods containing different types and amounts of RS (baked beans, pearl barley, cornflakes, and whole and ground rice). The total amount of starch escaping digestion and recovered in the effluent (ranging from 5.7% in baked beans to 0.7% in ground rice) was compared with results obtained by using the in vitro assay with an incubation time of 6 h. The assay was found to be a good qualitative predictor (r = 0.90, P < 0.05), but a poor quantitative predictor of RS amounts. Increasing the duration of incubation with alpha-amylase and amyloglucosidase to 15 h resulted in a very close agreement between results from the in vitro technique and the in vivo model. These data indicate that for a variety of foods the in vitro assay produced an excellent estimate of starch escaping digestion in the small intestine of humans.
Article
To determine if uncooked cornstarch, as part of the evening snack, can avert nocturnal hypoglycemia in type 1 diabetes. Fifty-one campers and counselors at the American Diabetes Association Camp in San Bernardino, CA were randomly assigned to receive 5 g of uncooked cornstarch as part of the 21:00 evening snack vs. a standard snack of equivalent carbohydrate content. Each snack was given for five nights and the participants and medical personnel were blinded as to assignment. Midnight and 07:00 finger stick blood glucose levels were compared with values <60 mg/dl defined as hypoglycemia and values > 250 mg/dl defined as hyperglycemia. There were 218 midnight and 222 07:00 values for comparison. There were six episodes of hypoglycemia at midnight and nine episodes of hypoglycemia at 07:00 for the cornstarch snack nights vs. 30 hypoglycemia episodes at midnight and 21 at 07:00 for the standard snack nights (P < 0.001 and <0.05, respectively). There was no difference in the number of hyperglycemic events at midnight or 07:00 for the cornstarch vs. standard snack nights. At midnight, 12% of campers had hypoglycemia after the cornstarch snack vs. 46% after the standard snack (P < 0.001), and at 07:00, 16% had hypoglycemia after cornstarch vs. 26% after the standard snack (P = 0.327). These data suggest that uncooked cornstarch, as part of the evening snack, can diminish the nighttime and morning hypoglycemia associated with type 1 diabetes, without causing hyperglycemia.
Article
To see if both the amount and source of carbohydrate consumed determined postprandial glucose and insulin responses of mixed meals, eight nondiabetic subjects took five different mixed meals containing variable energy (1650-2550 kJ), fat (8-24 g), protein (12-25 g) carbohydrate (38-104 g) and glycemic index (43-99). Incremental glucose and insulin responses for the five meals varied over a 2.3-fold range. Amount of carbohydrate alone was not significantly related to the mean glucose and insulin responses. However, using previously derived equations, amount of carbohydrate and glycemic index explained approximately 90% of the variability of the observed mean glucose and insulin responses (P = 0.01). We conclude that both amount and source of carbohydrate determine the glucose and insulin responses of lean, young, nondiabetic subjects after different mixed meals with variable glycemic index. Variation in protein and fat intake, over the range tested here, appears to have a negligible effect on postprandial glucose and insulin.
Article
To determine if source and amount of carbohydrate affected postprandial glucose and insulin responses, seven nondiabetic subjects consumed 0, 25, 50, 75 or 100 g carbohydrate (total carbohydrate minus total dietary fiber) portions of barley, spaghetti, bread or potato. By ANOVA, both source and amount of carbohydrate had significant effects on incremental response areas for capillary glucose (P = 0.001), plasma glucose (P = 0.01) and plasma insulin (P = 0.03), but there was no source x amount interaction. By regression analysis, source of carbohydrate explained a similar amount of the variability of glucose and insulin responses, 46-64%, as the amount of carbohydrate, 47-57%. Together, carbohydrate source and amount accounted for 85-94% of the variability of mean glucose and insulin responses. We conclude that, for individual foods with different glycemic indices, both source and amount of carbohydrate influence the postprandial glucose and insulin responses of nondiabetic subjects.
Article
This study was designed to assess the potential toxicity of pullulan, a starch-like substance produced by Aureobasidium pullulans that is proposed for use as a texturizer for meat and meat substitutes and as a flavour substrate. Sprague-Dawley rats (15/sex/group) were administered pullulan as a dietary admixture at levels of 1, 5 and 10% for a period of 62 wk. Control animals (15/sex) received untreated standard laboratory diet. The feeding study, originally intended to continue for 24 months, was terminated at 62 wk due to poor survival resulting from intercurrent pneumonia which was confirmed by histological findings. At 62 wk of treatment, all survivors were killed, complete gross post-mortem examinations were conducted on all animals, selected organs were weighed and organ/body weight and organ/brain weight ratios calculated. Mean body weights of all treated groups were comparable to controls. There were no indications of an adverse effect of pullulan on food consumption or food efficiency. At termination of the study, haematology and clinical chemistry values of treated animals were comparable to control values. There was no indication of pullulan-related toxicity in terminal organ and body weights. Macroscopic and microscopic examinations revealed no toxic lesions due to treatment. The mutagenicity of pullulan was assessed with and without metabolic activation in Salmonella typhimurium (TA100, TA1535, TA98 and TA1537). Pullulan did not increase the number of revertants per plate in any strain at any dose, including 10,000 micrograms/plate with or without metabolic activation, suggesting that it lacks mutagenic/carcinogenic potential on the basis of these results, it is concluded that pullulan lacks significant toxicological activity. The no-observed-adverse-effect level was 10% (equal to or greater than 4450 mg/kg body weight/day in males and 5080 mg/kg body weight/day in females) which would support use in various foods as a substrate for flavours.
Article
Differences in glycemic and insulinemic responses to dietary starch are directly related to the rate of starch digestion. Chemical modification of starch may allow for the production of a slowly digested starch that could be used for the treatment of certain medical modalities. An in vitro method was utilized to evaluate the effects of chemical modification on the rate and extent of raw and cooked starch digestion. The extent of starch digestion was significantly reduced by dextrinization, etherification, and oxidation. However, the rate of starch digestion was not significantly affected by chemical modification. For most modified starches, as the degree of modification increased, the extent of digestion decreased, suggesting an increase in the amount of resistant starch. The results of this study suggest that chemically modified starch has a metabolizable energy value of <16.7 kJ/g. Chemically modified starch ingredients may serve as a good source of resistant starch in human and animal diets.
Article
To evaluate the glycemic response to a food starch esterified by 1-octenyl succinic anhydride (OSA), 30 healthy nondiabetic adult subjects were studied in a double-blind crossover design. After an overnight fast, subjects consumed a product containing either 25 g of glucose or 25 g of OSA-substituted starch. Finger-prick capillary blood was obtained at baseline and 15, 30, 45, 60, 90, and 120 min postprandial for glucose measurement. After OSA treatment, the rise in blood glucose was reduced (P < 0.05) at 15 and 30 min and tended (P < 0.08) to be lower at 45 min. Mean peak rise in glucose was reduced 19% (P < 0.01) by OSA (3.30 +/- 0.19 versus 2.66 +/- 0.16 mmol/L) compared to glucose, but time to peak did not differ between treatments. Net incremental area under the curve was also lower (P < 0.05) on OSA compared to glucose. Minimal effects on gastrointestinal symptoms (intensity and frequency of nausea, cramping, distention, and flatulence) were noted for both products, with no clinically significant difference between products. In conclusion, starch substitution with OSA attenuated the postprandial glycemic excursion compared to an equivalent glucose challenge and was well tolerated by fasting healthy adult subjects.
Article
Obese and diabetic patients may benefit from foodstuffs that are poorly absorbed and/or digested at a slower rate. Prowashonupana (PW) is a cultivar of barley, whose grains are enriched in beta-glucans, and thus may be less digestible than standard barley (barley cultivar (BZ) 594.35.e). To test this, both kinds of barley were grown in a chamber into which (13)CO(2) was injected. On two occasions, 10 healthy hydrogen (H(2))-producing adults consumed in random order one 35-g portion of each of the cooked, dehulled (13)C-enriched grains. CO(2) production was measured in a whole-body direct calorimeter, and H(2) and (13)CO(2) were measured in breath at baseline and intermittently for 450 min. The percentage of the (13)C dose recovered in breath was calculated. Results were compared by repeated measures analysis of variance (ANOVA). The percentage of the (13)C dose oxidized was greater after BZ than after PW consumption (P < 0.05). The area under the curve for H(2) was greater after PW (mean +/- SD, 8658 +/- 6582) than after BZ (5178 +/- 4759) intake (P < 0.05), whereas there was no difference in CO(2) production. We conclude that absorption of PW is significantly lower than that of BZ, making the modified barley appropriate for obese and diabetic patients.
linked dextrin determined in rats
  • K Tsuji
  • D T Gordon
Tsuji, K. & Gordon, D. T.(1998) linked dextrin determined in rats. J. Agric. Food Chem. 46: 2253–2259.