A Holistic View of Dietary Carbohydrate Utilization in Lobster: Digestion, Postprandial Nutrient Flux, and Metabolism

PubMed Central

Casuso, Antonio; Perdomo-Morales, Rolando; Gutierrez, Odilia; Scull, Idania; Carrillo, Olimpia; Martos-Sitcha, Juan A.; García-Galano, Tsai; Mancera, Juan Miguel

2014-01-01

Crustaceans exhibit a remarkable variation in their feeding habits and food type, but most knowledge on carbohydrate digestion and utilization in this group has come from research on few species. The aim of this study was to make an integrative analysis of dietary carbohydrate utilization in the spiny lobster Panulirus argus. We used complementary methodologies such as different assessments of digestibility, activity measurements of digestive and metabolic enzymes, and post-feeding flux of nutrients and metabolites. Several carbohydrates were well digested by the lobster, but maize starch was less digestible than all other starches studied, and its inclusion in diet affected protein digestibility. Most intense hydrolysis of carbohydrates in the gastric chamber of lobster occurred between 2–6 h after ingestion and afterwards free glucose increased in hemolymph. The inclusion of wheat in diet produced a slow clearance of glucose from the gastric fluid and a gradual increase in hemolymph glucose. More intense hydrolysis of protein in the gastric chamber occurred 6–12 h after ingestion and then amino acids tended to increase in hemolymph. Triglyceride concentration in hemolymph rose earlier in wheat-fed lobsters than in lobsters fed other carbohydrates, but it decreased the most 24 h later. Analyses of metabolite levels and activities of different metabolic enzymes revealed that intermolt lobsters had a low capacity to store and use glycogen, although it was slightly higher in wheat-fed lobsters. Lobsters fed maize and rice diets increased amino acid catabolism, while wheat-fed lobsters exhibited higher utilization of fatty acids. Multivariate analysis confirmed that the type of carbohydrate ingested had a profound effect on overall metabolism. Although we found no evidence of a protein-sparing effect of dietary carbohydrate, differences in the kinetics of their digestion and absorption impacted lobster metabolism determining the fate of other nutrients. PMID

Changes in molecular characteristics of cereal carbohydrates after processing and digestion.

PubMed

Kasprzak, Mirosław Marek; Lærke, Helle Nygaard; Knudsen, Knud Erik Bach

2012-12-10

Different extraction, purification and digestion methods were used to investigate the molecular properties of carbohydrates in arabinoxylan and β-glucan concentrates, dietary fiber (DF) rich breads and ileum content of bread fed pigs. The breads studied were: a low DF wheat bread (WF), whole meal rye bread (GR), rye bread with kernels (RK), wheat bread supplemented with wheat arabinoxylan concentrate (AX) and wheat bread supplemented with oat β-glucan concentrate (BG). The weight average molecular weight (M(w)) of extractable carbohydrates in β-glucan concentrate decreased eight-fold after inclusion in the BG bread when exposed to in vitro digestion, while the M(w) of purified extractable carbohydrates in AX bread was reduced two-fold, and remained almost unaffected until reaching the terminal ileum of pigs. Similarly, the M(w) of purified extractable carbohydrates in GR and RK bread was not significantly changed in the ileum. The AX bread resulted in the highest concentration of dissolved arabinoxylan in the ileum among all the breads that caused a substantial increased in ileal AX viscosity. Nevertheless, for none of the breads, the M(w) of extractable carbohydrates was related neither to the bread extract nor ileal viscosity.

Changes in Molecular Characteristics of Cereal Carbohydrates after Processing and Digestion

PubMed Central

Kasprzak, Mirosław Marek; Lærke, Helle Nygaard; Knudsen, Knud Erik Bach

2012-01-01

Different extraction, purification and digestion methods were used to investigate the molecular properties of carbohydrates in arabinoxylan and β-glucan concentrates, dietary fiber (DF) rich breads and ileum content of bread fed pigs. The breads studied were: a low DF wheat bread (WF), whole meal rye bread (GR), rye bread with kernels (RK), wheat bread supplemented with wheat arabinoxylan concentrate (AX) and wheat bread supplemented with oat β-glucan concentrate (BG). The weight average molecular weight (Mw) of extractable carbohydrates in β-glucan concentrate decreased eight-fold after inclusion in the BG bread when exposed to in vitro digestion, while the Mw of purified extractable carbohydrates in AX bread was reduced two-fold, and remained almost unaffected until reaching the terminal ileum of pigs. Similarly, the Mw of purified extractable carbohydrates in GR and RK bread was not significantly changed in the ileum. The AX bread resulted in the highest concentration of dissolved arabinoxylan in the ileum among all the breads that caused a substantial increased in ileal AX viscosity. Nevertheless, for none of the breads, the Mw of extractable carbohydrates was related neither to the bread extract nor ileal viscosity. PMID:23222731

In vitro study of prebiotic properties of levan-type exopolysaccharides from Lactobacilli and non-digestible carbohydrates using denaturing gradient gel electrophoresis.

PubMed

Bello, F D; Walter, J; Hertel, C; Hammes, W P

2001-07-01

Batch cultures inoculated with human faeces were used to study the prebiotic properties of levan-type exopolysaccharides (EPS) from Lactobacillus sanfranciscensis as well as levan, inulin, and fructooligosaccharide (FOS). Denaturing gradient gel electrophoresis of 16S rDNA fragments generated by PCR with universal primers was used to analyse the cultures. Characteristic changes were revealed in the composition of the gut bacteria during fermentation of the carbohydrates. An enrichment of Bifidobacterium spp. was found for the EPS and inulin but not for levan and FOS. The bifidogenic effect of the EPS was confirmed by culturing on selective medium. In addition, the use of EPS and FOS resulted in enhanced growth of Eubacterium biforme and Clostridium perfringens, respectively.

Degradation properties of protein and carbohydrate during sludge anaerobic digestion.

PubMed

Yang, Guang; Zhang, Panyue; Zhang, Guangming; Wang, Yuanyuan; Yang, Anqi

2015-09-01

Degradation of protein and carbohydrate is vital for sludge anaerobic digestion performance. However, few studies focused on degradation properties of protein and carbohydrate. This study investigated detailed degradation properties of sludge protein and carbohydrate in order to gain insight into organics removal during anaerobic digestion. Results showed that carbohydrate was more efficiently degraded than protein and was degraded prior to protein. The final removal efficiencies of carbohydrate and protein were 49.7% and 32.2%, respectively. The first 3 days were a lag phase for protein degradation since rapid carbohydrate degradation in this phase led to repression of protease formation. Kinetics results showed that, after initial lag phase, protein degradation followed the first-order kinetic with rate constants of 0.0197 and 0.0018 d(-1) during later rapid degradation phase and slow degradation phase, respectively. Carbohydrate degradation also followed the first-order kinetics with a rate constant of 0.007 d(-1) after initial quick degradation phase. Copyright © 2015 Elsevier Ltd. All rights reserved.

Physiochemical Characteristics and Molecular Structures for Digestible Carbohydrates of Silages.

PubMed

Refat, Basim; Prates, Luciana L; Khan, Nazir A; Lei, Yaogeng; Christensen, David A; McKinnon, John J; Yu, Peiqiang

2017-10-18

The main objectives of this study were (1) to assess the magnitude of differences among new barley silage varieties (BS) selected for varying rates of in vitro neutral detergent fiber (NDF) digestibility (ivNDFD; Cowboy BS with higher ivNDFD, Copeland BS with intermediate ivNDFD, and Xena BS with lower ivNDFD) with regard to their carbohydrate (CHO) molecular makeup, CHO chemical fractions, and rumen degradability in dairy cows in comparison with a new corn silage hybrid (Pioneer 7213R) and (2) to quantify the strength and pattern of association between the molecular structures and digestibility of carbohydrates. The carbohydrate-related molecular structure spectral data was measured using advanced vibrational molecular spectroscopy (FT/IR). In comparison to BS, corn silage showed a significantly (P < 0.05) higher level of starch and energy content and higher degradation of dry matter (DM). Cowboy BS had lower feeding value (higher indigestible fiber content and lower starch content) and lower DM degradation in the rumen compared to other BS varieties (P < 0.05). The spectral intensities of carbohydrates were significantly (P < 0.05) correlated with digestible carbohydrate content of the silages. In conclusion, the univariate approach with only one-factor consideration (ivNDFD) might not be a satisfactory method for evaluating and ranking BS quality. FT/IR molecular spectroscopy can be used to evaluate silage quality rapidly, particularly the digestible fiber content.

Wholegrain oat-based cereals have prebiotic potential and low glycaemic index.

PubMed

Connolly, M L; Tuohy, K M; Lovegrove, J A

2012-12-28

Population studies show a positive association between increased dietary intake of wholegrains and reduced risk of cardiometabolic disorders. Consumption of wholegrain food has been associated with lower blood glucose and therefore may contribute to a low-glycaemic load diet. The ability to mediate a prebiotic modulation of gut microbiota has recently been suggested to have an inverse correlation with risk of cardiometabolic disease. To date very little work has been carried out on the functionality of wholegrain breakfast cereals in terms of glycaemic response or impact on gut microbiota. An investigation into identifying wholegrain-based breakfast cereals demonstrating both low glycaemic index (GI) and prebiotic attributes was performed. After in vitro digestion, cereal samples were supplemented to pH-controlled anaerobic batch cultures of the human faecal microbiota. Total bacteria populations increased significantly (P < 0·05) in all treated cultures, and the fermentation of a wholegrain oat cluster cereal was associated with proliferation of the Bifidobacterium genus (P = 0·02). Smaller, but significant increases in the Bifidobacterium genus were observed for a further four oat-based cereals. Significant increases in the Lactobacillus-Enterococcus group were observed for granola (P = 0·01), 100 % wholegrain aggregate (P = 0·04) and 70 % wholegrain loops (P = 0·01). Cereals demonstrating prebiotic potential were selected for GI determination in twelve healthy subjects. The wholegrain oat aggregate cereal achieved the lowest GI value (40), three other cereals ranged between 44 and 74, with instant porridge resulting in a GI value similar to the standard glucose control. The present study suggests that wholegrain oat-based breakfast cereals may be prebiotics and have the potential to have low GI.

Fiber and Prebiotics: Mechanisms and Health Benefits

PubMed Central

Slavin, Joanne

2013-01-01

The health benefits of dietary fiber have long been appreciated. Higher intakes of dietary fiber are linked to less cardiovascular disease and fiber plays a role in gut health, with many effective laxatives actually isolated fiber sources. Higher intakes of fiber are linked to lower body weights. Only polysaccharides were included in dietary fiber originally, but more recent definitions have included oligosaccharides as dietary fiber, not based on their chemical measurement as dietary fiber by the accepted total dietary fiber (TDF) method, but on their physiological effects. Inulin, fructo-oligosaccharides, and other oligosaccharides are included as fiber in food labels in the US. Additionally, oligosaccharides are the best known “prebiotics”, “a selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microflora that confers benefits upon host well-bring and health.” To date, all known and suspected prebiotics are carbohydrate compounds, primarily oligosaccharides, known to resist digestion in the human small intestine and reach the colon where they are fermented by the gut microflora. Studies have provided evidence that inulin and oligofructose (OF), lactulose, and resistant starch (RS) meet all aspects of the definition, including the stimulation of Bifidobacterium, a beneficial bacterial genus. Other isolated carbohydrates and carbohydrate-containing foods, including galactooligosaccharides (GOS), transgalactooligosaccharides (TOS), polydextrose, wheat dextrin, acacia gum, psyllium, banana, whole grain wheat, and whole grain corn also have prebiotic effects. PMID:23609775

Invitro Digestion and Fermentation Characteristics of Temulose Molasses, a Co-Product of Fiberboard Production, and Select Temulose Fractions

USDA-ARS?s Scientific Manuscript database

It is of interest to discover new fermentable carbohydrates sources that function as prebiotics. This study evaluated the hydrolytic digestibility, fermentative capacity, and microbiota modulating properties of temulose molasses, four hydrolyzed fractions of temulose molasses, short-chain fructooli...

The effects of the proportions of dietary macronutrients on the digestibility, post-prandial endocrine responses and large intestinal fermentation of carbohydrate in working dogs.

PubMed

Hill, S R; Rutherfurd-Markwick, K J; Ravindran, G; Ugarte, C E; Thomas, D G

2009-12-01

To compare the effects of feeding diets varying in the proportions of macronutrients on the digestibility, post-prandial endocrine responses and large intestinal fermentation of carbohydrate in working dogs. The apparent digestibility of two test diets, one comprising low-carbohydrate, high-protein dry biscuits (Diet 1), and one comprising high-carbohydrate, low-protein dry biscuits (Diet 2), fed to 12 adult Harrier Hounds (n=5 female), was determined using the indigestible-marker and total-collection methods. Serial breath samples were collected from each dog before and after feeding, and analysed for concentrations of hydrogen. Concentrations of glucose and insulin in plasma were established from serial blood samples obtained after feeding. The apparent dry matter, protein, fat and energy digestibility of Diet 1 were higher, but the carbohydrate digestibility was lower (p<0.05), than those of Diet 2. The apparent digestibility values determined using the total-collection method were lower (p<0.05) for carbohydrates, and tended to be lower for dry matter and energy (p<0.10) than those determined using the indigestible-marker method, but the values for protein and fat digestibility were similar using the two methods of determination. The maximum concentration (Cmax) of hydrogen detected in the breath of the dogs occurred earlier for Diet 1 than Diet 2 (p<0.01). However, the Cmax and area under the curve (AUC) for breath hydrogen were higher in the dogs fed Diet 2 than Diet 1 (p<0.01). The Cmax for glucose and insulin in plasma occurred earlier in dogs fed Diet 2 compared with those fed Diet 1 (p<0.05). However, the Cmax for glucose, and AUC for glucose and for insulin were not different between the two diets. The Cmax for insulin was greater for Diet 2 compared with Diet 1 (p<0.05). The low-carbohydrate, high-protein diet (Diet 1) appeared to offer certain advantages to working dogs, including higher apparent nutrient digestibility, slower release of glucose into

The role and requirements of digestible dietary carbohydrates in infants and toddlers

PubMed Central

Stephen, A; Alles, M; de Graaf, C; Fleith, M; Hadjilucas, E; Isaacs, E; Maffeis, C; Zeinstra, G; Matthys, C; Gil, A

2012-01-01

Digestible carbohydrates are one of the main sources of dietary energy in infancy and childhood and are essential for growth and development. The aim of this narrative review is to outline the intakes of digestible carbohydrates and their role in health and disease, including the development of food preferences, as well the consequences of excess carbohydrate. Key experts in these fields provided up-to-date reviews of the literature. A search of available information on dietary intakes of children below the age of 4 years was conducted from 1985 up to 2010. Articles and reports including information about sugars and/or starch intakes were selected. A number of factors limit the ability to obtain an overall picture of carbohydrate intakes and food sources in this age group. These include small numbers of intake studies, differing approaches to analysing carbohydrate, a variety of terms used to describe sugars intakes and a dearth of information about starch intakes. Data suggest that sweet taste is preferred in infancy and later food choices. There are few established adverse consequences of high intakes of digestible carbohydrate for young children. The greatest evidence is for dental caries, although this is influenced by high intake frequency and poor oral hygiene. Evidence for detrimental effects on nutrient dilution, obesity, diabetes or cognition is limited. In infants, minimum carbohydrate (mainly lactose) intake should be 40% of total energy, gradually increasing to 55% energy by the age of 2 years. PMID:22473042

More sugar? No, thank you! The elusive nature of low carbohydrate diets.

PubMed

Giugliano, Dario; Maiorino, Maria Ida; Bellastella, Giuseppe; Esposito, Katherine

2018-03-19

In the past decades, dietary guidelines focused on reducing saturated fat as the primary strategy for cardiovascular disease prevention, neglecting the many other potential effects of diet on health, in particular the harmful effects of sugar. A greater intake of soft drinks (sugar-sweetened beverages), for example, is associated with a 44% increased prevalence of metabolic syndrome, a higher risk of obesity, and a 26% increased risk of developing diabetes mellitus. Carbohydrates comprise around 55% of the typical western diet, ranging from 200 to 350 g/day in relation to a person's overall caloric intake. For long-term weight gain, food rich in refined grains, starches, and sugar appear to be major culprits. Low-carbohydrate diets restrict daily carbohydrates between 20 and 50 g, as in clinical ketogenic diets. The results of controlled trials show that people on ketogenic diets (a diet with no more than 50 g carbohydrates/day) tend to lose more weight than people on low-fat diets. Moreover, there is no good evidence for recommending low-fat diets, as low-carbohydrate diets lead to significantly greater weight loss (1.15 kg) than did low-fat interventions. However, the magnitude of such a benefit is small. As the quality of ingested carbohydrates seems more important than the quantity for health outcomes, people with metabolic disorders should avoid or substantially reduce low-fiber, rapidly digested, refined grains, starches, and added sugars. So, the consumption of the right carbohydrates (high-fiber, slowly digested, and whole grains), in a moderately lower amount (between 40 and 50% of daily energy content), is compatible with a state of good health and may represent a scientifically-based and palatable choice for people with metabolic disorders.

Physical modification of palm kernel meal improved available carbohydrate, physicochemical properties and in vitro digestibility in economic freshwater fish.

PubMed

Thongprajukaew, Karun; Yawang, Pinya; Dudae, Lateepah; Bilanglod, Husna; Dumrongrittamatt, Terdtoon; Tantikitti, Chutima; Kovitvadhi, Uthaiwan

2013-12-01

Unavailable carbohydrates are an important limiting factor for utilization of palm kernel meal (PKM) as aquafeed ingredients. The aim of this study was to improve available carbohydrate from PKM. Different physical modifications including water soaking, microwave irradiation, gamma irradiation and electron beam, were investigated in relation to chemical composition, physicochemical properties and in vitro carbohydrate digestibility using digestive enzymes from economic freshwater fish. Modified methods had significant (P < 0.05) effects on chemical composition by decreasing crude fiber and increasing available carbohydrates. Improvements in physicochemical properties of PKM, such as water solubility, microstructure, relative crystallinity and lignocellulosic spectra, were mainly achieved by soaking and microwave irradiation. Carbohydrate digestibility varied among the physical modifications tested (P < 0.05) and three fish species had different abilities to digest PKM. Soaking was the appropriate modification for increasing carbohydrate digestion specifically in Nile tilapia (Oreochromis niloticus), whereas either soaking or microwave irradiation was effective for striped snakehead (Channa striata). For walking catfish (Clarias batrachus), carbohydrate digestibility was similar among raw, soaked and microwave-irradiated PKM. These findings suggest that soaking and microwave irradiation could be practical methods for altering appropriate physicochemical properties of PKM as well as increasing carbohydrate digestibility in select economic freshwater fish. © 2013 Society of Chemical Industry.

Microbial degradation of complex carbohydrates in the gut.

PubMed

Flint, Harry J; Scott, Karen P; Duncan, Sylvia H; Louis, Petra; Forano, Evelyne

2012-01-01

Bacteria that colonize the mammalian intestine collectively possess a far larger repertoire of degradative enzymes and metabolic capabilities than their hosts. Microbial fermentation of complex non-digestible dietary carbohydrates and host-derived glycans in the human intestine has important consequences for health. Certain dominant species, notably among the Bacteroidetes, are known to possess very large numbers of genes that encode carbohydrate active enzymes and can switch readily between different energy sources in the gut depending on availability. Nevertheless, more nutritionally specialized bacteria appear to play critical roles in the community by initiating the degradation of complex substrates such as plant cell walls, starch particles and mucin. Examples are emerging from the Firmicutes, Actinobacteria and Verrucomicrobium phyla, but more information is needed on these little studied groups. The impact of dietary carbohydrates, including prebiotics, on human health requires understanding of the complex relationship between diet composition, the gut microbiota and metabolic outputs.

Cats and Carbohydrates: The Carnivore Fantasy?

PubMed Central

Verbrugghe, Adronie; Hesta, Myriam

2017-01-01

The domestic cat’s wild ancestors are obligate carnivores that consume prey containing only minimal amounts of carbohydrates. Evolutionary events adapted the cat’s metabolism and physiology to this diet strictly composed of animal tissues and led to unique digestive and metabolic peculiarities of carbohydrate metabolism. The domestic cat still closely resembles its wild ancestor. Although the carnivore connection of domestic cats is well recognised, little is known about the precise nutrient profile to which the digestive physiology and metabolism of the cat have adapted throughout evolution. Moreover, studies show that domestic cats balance macronutrient intake by selecting low-carbohydrate foods. The fact that cats evolved consuming low-carbohydrate prey has led to speculations that high-carbohydrate diets could be detrimental for a cat’s health. More specifically, it has been suggested that excess carbohydrates could lead to feline obesity and diabetes mellitus. Additionally, the chances for remission of diabetes mellitus are higher in cats that consume a low-carbohydrate diet. This literature review will summarise current carbohydrate knowledge pertaining to digestion, absorption and metabolism of carbohydrates, food selection and macronutrient balancing in healthy, obese and diabetic cats, as well as the role of carbohydrates in prevention and treatment of obesity and diabetes mellitus. PMID:29140289

Prebiotics: Definition and protective mechanisms.

PubMed

Valcheva, Rosica; Dieleman, Levinus A

2016-02-01

The increase in chronic metabolic and immunologic disorders in the modern society is linked to major changes in the dietary patterns. These chronic conditions are associated with intestinal microbiota dysbiosis where important groups of carbohydrate fermenting, short-chain fatty acids-producing bacteria are reduced. Dietary prebiotics are defined as a selectively fermented ingredients that result in specific changes in the composition and/or activity of the gastrointestinal microbiota, thus conferring benefit(s) upon host health. Application of prebiotics may then restore the gut microbiota diversity and activity. Unlike the previously accepted prebiotics definition, where a limited number of bacterial species are involved in the prebiotic activity, new data from community-wide microbiome analysis demonstrated a broader affect of the prebiotics on the intestinal microbiota. These new findings require a revision of the current definition. In addition, prebiotics may exert immunomodulatory effects through microbiota-independent mechanisms that will require future investigations involving germ-free animal disease models. Copyright © 2016 Elsevier Ltd. All rights reserved.

In vitro digestibility and prebiotic potential of curdlan (1 → 3)-β-d-glucan oligosaccharides in Lactobacillus species.

PubMed

Shi, Yuqin; Liu, Jun; Yan, Qiaojuan; You, Xin; Yang, Shaoqing; Jiang, Zhengqiang

2018-05-15

Prebiotic effects of curdlan (1 → 3)-β-d-glucan oligosaccharides (GOS) were examined. GOS was tolerant against simulated gastrointestinal digestion, as well as low pH, thermal, and Maillard reaction conditions likely occurred during food processing. Growth of tested Lactobacillus (L.) strains was improved by GOS except L. brevis NRRL B-4527. E. coli did not grow on GOS as the only carbon source. In vitro batch fermentation using human faecal microbiota showed that GOS significantly increased the population of Lactobacillus sp. followed by Bifidobacterium sp. and Bacteroides sp. Growth of L. strains on GOS produced lactic acid, acetic, and propionic acid with decreased culture medium pH. Utilization pattern of GOS by representative L. strains was strain dependent. GOS with degree of polymerization (DP) of 2 and 3 were readily consumed. Findings here indicated that curdlan GOS (DP = 2 and 3) are promising physiologically active prebiotics for improvement of human intestinal health. Copyright © 2018 Elsevier Ltd. All rights reserved.

Analysis of Prebiotic Oligosaccharides

NASA Astrophysics Data System (ADS)

Sanz, M. L.; Ruiz-Matute, A. I.; Corzo, N.; Martínez-Castro, I.

Carbohydrates and more specifically prebiotics, are complex mixtures of isomers with different degrees of polymerization (DP), monosaccharide units and/or glycosidic linkages. Many efforts are focused on the search for new products and the determination of their biological activity. However, the study of their chemical structure is fundamental to both acquire a basic knowledge of the carbohydrate and to increase the understanding of the mechanisms for their metabolic effect.

The effect on the blood lipid profile of soy foods combined with a prebiotic: a randomized controlled trial.

PubMed

Wong, Julia M W; Kendall, Cyril W C; de Souza, Russell; Emam, Azadeh; Marchie, Augustine; Vidgen, Ed; Holmes, Candice; Jenkins, David J A

2010-09-01

The value of soy protein as part of the cholesterol-lowering diet has been questioned by recent studies. The apparent lack of effect may relate to the absence of dietary factors that increase colonic fermentation and potentiate the cholesterol-lowering effect of soy. Therefore, unabsorbable carbohydrates (prebiotics) were added to the diet with the aim of increasing colonic fermentation and so potentially increasing the hypocholesterolemic effect of soy. Twenty-three hyperlipidemic adults (11 male, 12 female; 58 +/- 7 years old; low-density lipoprotein cholesterol [LDL-C], 4.18 +/- 0.58 mmol/L) completed three 4-week diet intervention phases-a low-fat dairy diet and 10 g/d prebiotic (oligofructose-enriched inulin, a fermentable carbohydrate), a soy food-containing diet (30 g/d soy protein, 61 mg/d isoflavones from soy foods) and 10 g/d placebo (maltodextrin), and a soy food-containing diet with 10 g/d prebiotic--in a randomized controlled crossover study. Intake of soy plus prebiotic resulted in greater reductions in LDL-C (-0.18 +/- 0.07 mmol/L, P = .042) and in ratio of LDL-C to high-density lipoprotein cholesterol (-0.28 +/- 0.11, P = .041) compared with prebiotic. In addition, high-density lipoprotein cholesterol was significantly increased on soy plus prebiotic compared with prebiotic (0.06 +/- 0.02 mmol/L, P = .029). Differences in bifidobacteria, total anaerobes, aerobes, and breath hydrogen did not reach significance. Soy foods in conjunction with a prebiotic resulted in significant improvements in the lipid profile, not seen when either prebiotic or soy alone was taken. Coingestion of a prebiotic may potentiate the effectiveness of soy foods as part of the dietary strategy to lower serum cholesterol. Copyright 2010 Elsevier Inc. All rights reserved.

Stability of prebiotic, laminaran oligosaccharide under food processing conditions

NASA Astrophysics Data System (ADS)

Chamidah, A.

2018-04-01

Prebiotic stability tests on laminaran oligosaccharide under food processing conditions were urgently performed to determine the ability of prebiotics deal with processing. Laminaran, oligosaccharide is produced from enzymatic hydrolysis. To further apply this prebiotic, it is necessary to test its performance on food processing. Single prebiotic or in combination with probiotic can improve human digestive health. The effectiveness evaluation of prebiotic should be taken into account in regards its chemical and functional stabilities. This study aims to investigate the stability of laminaran, oligosaccharide under food processing condition.

Physiological aspects of energy metabolism and gastrointestinal effects of carbohydrates.

PubMed

Elia, M; Cummings, J H

2007-12-01

The energy values of carbohydrates continue to be debated. This is because of the use of different energy systems, for example, combustible, digestible, metabolizable, and so on. Furthermore, ingested macronutrients may not be fully available to tissues, and the tissues themselves may not be able fully to oxidize substrates made available to them. Therefore, for certain carbohydrates, the discrepancies between combustible energy (cEI), digestible energy (DE), metabolizable energy (ME) and net metabolizable energy (NME) may be considerable. Three food energy systems are in use in food tables and for food labelling in different world regions based on selective interpretation of the digestive physiology and metabolism of food carbohydrates. This is clearly unsatisfactory and confusing to the consumer. While it has been suggested that an enormous amount of work would have to be undertaken to change the current ME system into an NME system, the additional changes may not be as great as anticipated. In experimental work, carbohydrate is high in the macronutrient hierarchy of satiation. However, studies of eating behaviour indicate that it does not unconditionally depend on the oxidation of one nutrient, and argue against the operation of a simple carbohydrate oxidation or storage model of feeding behaviour to the exclusion of other macronutrients. The site, rate and extent of carbohydrate digestion in, and absorption from the gut are key to understanding the many roles of carbohydrate, although the concept of digestibility has different meanings. Within the nutrition community, the characteristic patterns of digestion that occur in the small (upper) vs large (lower) bowel are known to impact in contrasting ways on metabolism, while in the discussion of the energy value of foods, digestibility is defined as the proportion of combustible energy that is absorbed over the entire length of the gastrointestinal tract. Carbohydrates that reach the large bowel are fermented to

Prebiotics and synbiotics: dietary strategies for improving gut health.

PubMed

Krumbeck, Janina A; Maldonado-Gomez, Maria X; Ramer-Tait, Amanda E; Hutkins, Robert W

2016-03-01

A wide range of dietary carbohydrates, including prebiotic food ingredients, fermentable fibers, and milk oligosaccharides, are able to produce significant changes in the intestinal microbiota. These shifts in the microbial community are often characterized by increased levels of bifidobacteria and lactobacilli. More recent studies have revealed that species of Faecalibacterium, Akkermansia, and other less well studied members may also be enriched. We review the implications of these recent studies on future design of prebiotics and synbiotics to promote gastrointestinal health. Investigations assessing the clinical outcomes associated with dietary modification of the gut microbiota have shown systemic as well as specific health benefits. Both prebiotic oligosaccharides comprised of a linear arrangement of simple sugars, as well as fiber-rich foods containing complex carbohydrates, have been used in these trials. However, individual variability and nonresponding study participants can make the outcome of dietary interventions less predictable. In contrast, synergistic synbiotics containing prebiotics that specifically stimulate a cognate probiotic provide additional options for personalized gut therapies. This review describes recent research on how prebiotics and fermentable fibers can influence the gut microbiota and result in improvements to human health.

In ovo injection of prebiotics and synbiotics affects the digestive potency of the pancreas in growing chickens.

PubMed

Pruszynska-Oszmalek, E; Kolodziejski, P A; Stadnicka, K; Sassek, M; Chalupka, D; Kuston, B; Nogowski, L; Mackowiak, P; Maiorano, G; Jankowski, J; Bednarczyk, M

2015-08-01

The purpose of the study was to examine the effect of 2 prebiotics and 2 synbiotics on the digestive potency of pancreas in 1-, 3-, 7-, 14-, 21-, and 34-day-old cockerels. Prebiotics (inulin and Bi²tos) and synbiotics (inulin + Lactococcus lactis subsp. lactis and Bi²tos + Lactococcus lactis subsp. cremoris) were injected in ovo into the air cell on the 12th d embryonic development. Their application increased the activity of amylase, lipase, and trypsin in the pancreas. The most pronounced changes were observed at the end of the investigated rearing period (d 34). The strongest stimulative effects on amylase were shown by both synbiotics, on lipase synbiotic Bi²tos + Lactococcus lactis subsp. cremoris, and on trypsin all the used prebiotics and synbiotics. Simultaneously, neither the absolute nor the relative mass of the pancreas in comparison to control group were changed. Also, the injected in ovo compounds did not cause a deterioration in the posthatching condition of the chicken liver, as determined by measurement of the activity of marker enzymes in the blood (alanine aminotransferase and aspartate aminotransferase). Treatment with the prebiotics and synbiotics did not change the feed conversion ratio but Bi²tos (galacto-oligosaccharide) and inulin (fructan) + Lactococcus lactis subsp. lactis significantly increased final BW. © 2015 Poultry Science Association Inc.

Digestibility of carbohydrates from rice-, oat- and wheat-based ready-to-eat breakfast cereals in children.

PubMed

Brighenti, F; Casiraghi, M C; Ciappellano, S; Crovetti, R; Testolin, G

1994-09-01

To study the effect of the presence and quality of dietary fibre in ready-to-eat (RTE) breakfast cereals on completeness of carbohydrate digestion in children and on starch susceptibility to alpha-amylase in vitro. A controlled intervention study. Eight 3-8-year-old healthy children. Completeness of digestion was evaluated by assessing the amount of carbohydrates apparently fermented into the colon using the breath-H2 technique after consumption in random order, of five breakfast tests containing boiled rice (either alone or supplemented with 3 g of lactulose) as reference food, or RTE cereals based on rice (low-fibre), wheat (high insoluble fibre) and oats (high-soluble fibre). The potential glycaemic impact of the products was estimated in vitro by assessing starch susceptibility to alpha-amylolysis using an enzymatic-dialysis method. Compared to boiled rice and to rice-based RTE cereal, wheat- and oat-based RTE cereals both significantly (P < 0.05) increased the amount of apparently fermented carbohydrates (+1.1 +/- 1.7% of total breakfast carbohydrate fermented for rice, +5.6 +/- 0.9% for wheat and +9.4 +/- 3.7% for oats; mean +/- SEM), calculated using the excess H2 in breath after lactulose as standard. All products showed similar in vitro digestibility, resulting in estimated glycaemic indexes of 117.5 (24.0) for rice, and 105.7 (14.1) for oats-based, 128.4 (17.6) for wheat-based, and 129.8 (16.6) [mean 95% CI)] for rice-based RTE cereals. Results suggest that the presence of fibre in RTE breakfast cereals, in particular soluble fibre, increases colonic fermentation in children whereas it seems not to affect glucose availability.

A combined metabolomic and phylogenetic study reveals putatively prebiotic effects of high molecular weight arabino-oligosaccharides when assessed by in vitro fermentation in bacterial communities derived from humans.

PubMed

Sulek, Karolina; Vigsnaes, Louise Kristine; Schmidt, Line Rieck; Holck, Jesper; Frandsen, Henrik Lauritz; Smedsgaard, Jørn; Skov, Thomas Hjort; Meyer, Anne S; Licht, Tine Rask

2014-08-01

Prebiotic oligosaccharides are defined by their selective stimulation of growth and/or activity of bacteria in the digestive system in ways claimed to be beneficial for health. However, apart from the short chain fatty acids, little is known about bacterial metabolites created by fermentation of prebiotics, and the significance of the size of the oligosaccharides remains largely unstudied. By in vitro fermentations in human fecal microbial communities (derived from six different individuals), we studied the effects of high-mass (HA, >1 kDa), low-mass (LA, <1 kDa) and mixed (BA) sugar beet arabino-oligosaccharides (AOS) as carbohydrate sources. Fructo-oligosaccharides (FOS) were included as reference. The changes in bacterial communities and the metabolites produced in response to incubation with the different carbohydrates were analyzed by quantitative PCR (qPCR) and Liquid Chromatography-Mass Spectrometry (LC-MS), respectively. All tested carbohydrate sources resulted in a significant increase of Bifidobacterium spp. between 1.79 fold (HA) and 1.64 fold (FOS) in the microbial populations after fermentation, and LC-MS analysis suggested that the bifidobacteria contributed to decomposition of the arabino-oligosaccharide structures, most pronounced in the HA fraction, resulting in release of the essential amino acid phenylalanine. Abundance of Lactobacillus spp. correlated with the presence of a compound, most likely a flavonoid, indicating that lactobacilli contribute to release of such health-promoting substances from plant structures. Additionally, the combination of qPCR and LC-MS revealed a number of other putative interactions between intestinal microbes and the oligosaccharides, which contributes to the understanding of the mechanisms behind prebiotic impact on human health. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Application of inulin in cheese as prebiotic, fat replacer and texturizer: a review.

PubMed

Karimi, Reza; Azizi, Mohammad Hossein; Ghasemlou, Mehran; Vaziri, Moharam

2015-03-30

Inulin is a food ingredient that belongs to a class of carbohydrates known as fructans. Nutritionally it has functional properties and health-promoting effects that include reduced calorie value, dietary fiber and prebiotic effects. Inulin is increasingly used in industrially processed dairy and non-dairy products because it is a bulking agent for use in fat replacement, textural modification and organoleptic improvement. Addition of inulin to different kinds of cheese can be beneficial in the manufacture of a reduced- or low-fat, texturized, symbiotic product. This paper gives an overview of some aspects of the microstructural, textural, rheological, prebiotic and sensorial effects of inulin incorporated in cheese as fat replacer, prebiotic and texture modifier. Copyright © 2014 Elsevier Ltd. All rights reserved.

Update: The Digestion and Absorption of Carbohydrate and Protein: Role of the Small Intestine.

ERIC Educational Resources Information Center

Leese, H. J.

1984-01-01

Discusses the role of the small intestine in the digestion and absorption of carbohydrates and proteins. Indicates as outdated the view that these materials must be broken down to monomeric units before absorption and that the gut secretes a mixture of digestive juices which brings about absorption. (JN)

Probiotics and prebiotics in the elderly

PubMed Central

Hamilton-Miller, J

2004-01-01

Probiotics (usually lactobacilli and bifidobacteria) and prebiotics (non-digestible oligosaccharides) have been shown to be useful in preventing certain disease conditions as well as possibly promoting specific aspects of health. In the present review, the evidence from clinical trials for benefits from probiotics and prebiotics to elderly populations is presented and discussed, specifically in respect of three common conditions found in the elderly. Both probiotics and prebiotics may be helpful in malnutrition, particularly in lactose intolerance and calcium absorption, and in constipation. Probiotics have been shown clearly to boost immunity in the elderly, but the clinical significance of this remains to be clarified. These results are encouraging, and further large scale studies seem justified to establish the place of probiotic and prebiotic supplements in elderly subjects. PMID:15299153

The role of condensed tannins in the nutritional value of Lotus pedunculatus for sheep. 2. Quantitative digestion of carbohydrates and proteins.

PubMed

Barry, T N; Manley, T R

1984-05-01

Primary growth vegetative Lotus pedunculatus containing 46 and 106 g/kg dry matter (DM) of total condensed tannin and 3 and 14 g/kg DM of free condensed tannin, was cut and fed fresh at hourly intervals (750 g DM/d) to sheep fitted with permanent cannulas into the rumen and duodenum. Low- and high-tannin lotus contained respectively 41.3 and 31.6 g total nitrogen/kg DM and 132 and 152 g lignin/kg DM. The two forms of lotus were similar in carbohydrate composition. Nutrient intake was recorded and faecal output measured by direct collection. Digesta flow to the duodenum was estimated by measuring dilution at the duodenum of inert ruthenium phenanthroline (Ru-P) and chromium-EDTA markers continuously infused into the rumen. Effects attributable to condensed tannins were assessed by comparing the digestion of the two diets, and by comparing the digestion of each with predicted values for non-tannin-containing fresh forages fed at similar intakes. Apparent digestibility of all nutrients measured was less for high- than for low-tannin lotus (P less than 0.01). The levels of cellulose digested ruminally and post- ruminally in both forms of lotus were similar to predicted values. However, less hemicellulose and readily fermentable carbohydrate (RFC; soluble carbohydrate + pectin) was digested in the rumen in sheep given both forms of lotus than would be predicted for non-tannin-containing fresh forage diets, but this was compensated for by greater post-ruminal absorption of both nutrients. Total N gains across the rumen (duodenal N flow--total N intake) were 1.8 and 10.5 g/d for low- and high-tannin lotus v. predicted losses of 3.7 and 2.1 g/d for non-tannin-containing fresh forages given at the same total N intakes. Post-ruminal digestion of non- amonia -N (NAN; proportion NAN flowing at duodenum) was 0.71 and 0.67 for low- and high-tannin lotus respectively v. 0.76 for comparable non-tannin-containing fresh forages. Energy absorbed as amino acids from the small

Healthy carbohydrates

USDA-ARS?s Scientific Manuscript database

Functional foods include dietary fiber consisting of health-promoting carbohydrates. We have produced novel prebiotics from orange peel and observed that they extend the shelf life of probiotic bacteria in synbiotics. Some pectic-oligosaccharides and xyloglucan-oligosaccharides also have anti-adhesi...

Antihypertensive Properties of Plant-Based Prebiotics

PubMed Central

Yeo, Siok-Koon; Ooi, Lay-Gaik; Lim, Ting-Jin; Liong, Min-Tze

2009-01-01

Hypertension is one of the major risk factors for cardiovascular disease. Although various drugs for its treatment have been synthesized, the occurring side effects have generated the need for natural interventions for the treatment and prevention of hypertension. Dietary intervention such as the administration of prebiotics has been seen as a highly acceptable approach. Prebiotics are indigestible food ingredients that bypass digestion and reach the lower gut as substrates for indigenous microflora. Most of the prebiotics used as food adjuncts, such as inulin, fructooligosaccharides, dietary fiber and gums, are derived from plants. Experimental evidence from recent studies has suggested that prebiotics are capable of reducing and preventing hypertension. This paper will discuss some of the mechanisms involved, the evidence generated from both in-vitro experiments and in-vivo trials and some controversial findings that are raised. PMID:20111692

An Introduction to the Avian Gut Microbiota and the Effects of Yeast-Based Prebiotic-Type Compounds as Potential Feed Additives

PubMed Central

Roto, Stephanie M.; Rubinelli, Peter M.; Ricke, Steven C.

2015-01-01

The poultry industry has been searching for a replacement for antibiotic growth promoters in poultry feed as public concerns over the use of antibiotics and the appearance of antibiotic resistance has become more intense. An ideal replacement would be feed amendments that could eliminate pathogens and disease while retaining economic value via improvements on body weight and feed conversion ratios. Establishing a healthy gut microbiota can have a positive impact on growth and development of both body weight and the immune system of poultry while reducing pathogen invasion and disease. The addition of prebiotics to poultry feed represents one such recognized way to establish a healthy gut microbiota. Prebiotics are feed additives, mainly in the form of specific types of carbohydrates that are indigestible to the host while serving as substrates to select beneficial bacteria and altering the gut microbiota. Beneficial bacteria in the ceca easily ferment commonly studied prebiotics, producing short-chain fatty acids, while pathogenic bacteria and the host are unable to digest their molecular bonds. Prebiotic-like substances are less commonly studied, but show promise in their effects on the prevention of pathogen colonization, improvements on the immune system, and host growth. Inclusion of yeast and yeast derivatives as probiotic and prebiotic-like substances, respectively, in animal feed has demonstrated positive associations with growth performance and modification of gut morphology. This review will aim to link together how such prebiotics and prebiotic-like substances function to influence the native and beneficial microorganisms that result in a diverse and well-developed gut microbiota. PMID:26664957

Expert consensus document: The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of prebiotics.

PubMed

Gibson, Glenn R; Hutkins, Robert; Sanders, Mary Ellen; Prescott, Susan L; Reimer, Raylene A; Salminen, Seppo J; Scott, Karen; Stanton, Catherine; Swanson, Kelly S; Cani, Patrice D; Verbeke, Kristin; Reid, Gregor

2017-08-01

In December 2016, a panel of experts in microbiology, nutrition and clinical research was convened by the International Scientific Association for Probiotics and Prebiotics to review the definition and scope of prebiotics. Consistent with the original embodiment of prebiotics, but aware of the latest scientific and clinical developments, the panel updated the definition of a prebiotic: a substrate that is selectively utilized by host microorganisms conferring a health benefit. This definition expands the concept of prebiotics to possibly include non-carbohydrate substances, applications to body sites other than the gastrointestinal tract, and diverse categories other than food. The requirement for selective microbiota-mediated mechanisms was retained. Beneficial health effects must be documented for a substance to be considered a prebiotic. The consensus definition applies also to prebiotics for use by animals, in which microbiota-focused strategies to maintain health and prevent disease is as relevant as for humans. Ultimately, the goal of this Consensus Statement is to engender appropriate use of the term 'prebiotic' by relevant stakeholders so that consistency and clarity can be achieved in research reports, product marketing and regulatory oversight of the category. To this end, we have reviewed several aspects of prebiotic science including its development, health benefits and legislation.

Net energy value of two low-digestible carbohydrates, Lycasin HBC and the hydrogenated polysaccharide fraction of Lycasin HBC in healthy human subjects and their impact on nutrient digestive utilization.

PubMed

Sinau, S; Montaunier, C; Wils, D; Verne, J; Brandolini, M; Bouteloup-Demange, C; Vermorel, M

2002-02-01

The metabolizable energy content of low-digestible carbohydrates does not correspond with their true energy value. The aim of the present study was to determine the tolerance and effects of two polyols on digestion and energy expenditure in healthy men, as well as their digestible, metabolizable and net energy values. Nine healthy men were fed for 32 d periods a maintenance diet supplemented either with dextrose, Lycasin HBC (Roquette Frères, Lestrem, France), or the hydrogenated polysaccharide fraction of Lycasin HBC, at a level of 100 g DM/d in six equal doses per d according to a 3 x 3 Latin square design with three repetitions. After a 20 d progressive adaptation period, food intake was determined for 12d using the duplicate meal method and faeces and urine were collected for 10 d for further analyses. Subjects spent 36 h in one of two open-circuit whole-body calorimeters with measurements during the last 24h. Ingestion of the polyols did not cause severe digestive disorders, except excessive gas emission, and flatulence and gurgling in some subjects. The polyols induced significant increases in wet (+45 and +66% respectively, P<0.01) and dry (+53 and +75 % respectively, P<0.002) stool weight, resulting in a 2% decrease in dietary energy digestibility (P<0.001). They resulted also in significant increases in sleeping (+4.1%, P<0.03) and daily energy expenditure (+2.7 and +2.9% respectively, P<0.02) compared with dextrose ingestion. The apparent energy digestibility of the two polyols was 0.82 and 0.79 respectively, their metabolizable energy value averaged 14.1 kJ/g DM, and their net energy value averaged 10.8 kJ/g DM, that is, 35 % less than those of sucrose and starch.

Prebiotics and gut microbiota in chickens.

PubMed

Pourabedin, Mohsen; Zhao, Xin

2015-08-01

Prebiotics are non-digestible feed ingredients that are metabolized by specific members of intestinal microbiota and provide health benefits for the host. Fermentable oligosaccharides are best known prebiotics that have received increasing attention in poultry production. They act through diverse mechanisms, such as providing nutrients, preventing pathogen adhesion to host cells, interacting with host immune systems and affecting gut morphological structure, all presumably through modulation of intestinal microbiota. Currently, fructooligosaccharides, inulin and mannanoligosaccharides have shown promising results while other prebiotic candidates such as xylooligosaccharides are still at an early development stage. Despite a growing body of evidence reporting health benefits of prebiotics in chickens, very limited studies have been conducted to directly link health improvements to prebiotic-dependent changes in the gut microbiota. This article visits the current knowledge of the chicken gastrointestinal microbiota and reviews most recent publications related to the roles played by prebiotics in modulation of the gut microbiota and immune functions. Progress in this field will help us better understand how the gut microbiota contributes to poultry health and productivity, and support the development of new prebiotic products as an alternative to in-feed antibiotics. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Mechanisms of Prebiotic Impact on Health

NASA Astrophysics Data System (ADS)

Steed, H.; Macfarlane, S.

Prebiotics were originally defined as non-digestible food ingredients that beneficially affect the host by selectively stimulating the growth and/or activities of one or a limited number of bacteria in the colon, thereby improving host health (Gibson and Roberfroid, 1995). However, a more recent definition is that “A prebiotic is a selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microbiota that confers benefits upon host wellbeing and health” (Gibson et al., 2004). The principal concept associated with both of these definitions is that the prebiotic has a selective effect on the microbiota that results in an improvement in the health of the host. Common prebiotics in use include inulins, fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), soya-oligosaccharides, xylo-oligosaccharides, pyrodextrins, isomalto-oligosaccharides and lactulose. The majority of studies carried out to date have focused on inulin, FOS and GOS (Macfarlane et al., 2008).

Prebiotic index evaluation of crude laminaran of Sargassum sp. using feces of wistar rats

NASA Astrophysics Data System (ADS)

Chamidah, A.

2018-03-01

Today, prebiotics are often added to food. This compound is a food substance which could not be digested, yet benefiting the host by selectively stimulating the growth or activity of one or more bacteria in the colon to improve the health of the host. One of the foodstuffs derived from algae, which could not be digested is laminaran (β-Glucan). The relationship between microflora with the added prebiotics was tested by measuring their prebiotic index, which is supported by total sugars and laminaran levels. The results showed that total sugar content of Laminaran Acid Extract (LAE) (9.075 %) was higher than that of Laminaran Modified Extract (LME) (7.355 %), while the laminaran level of LME (42.23 %) was higher than that of LAE (30.92 %). HPLC test result confirmed the presence of laminaran. The obtained prebiotic index values of LAE and LME were 1.29 and 2.10, respectively, with a negative index score for LAE prebiotic, yet positive one for LME in terms of probiotic from Lactobacillus group. Laminaran extract, especially LME, deserves to be regarded as a prebiotic candidate.

Low-Fat Versus Low-Carbohydrate Weight Reduction Diets

PubMed Central

Bradley, Una; Spence, Michelle; Courtney, C. Hamish; McKinley, Michelle C.; Ennis, Cieran N.; McCance, David R.; McEneny, Jane; Bell, Patrick M.; Young, Ian S.; Hunter, Steven J.

2009-01-01

OBJECTIVE Low-fat hypocaloric diets reduce insulin resistance and prevent type 2 diabetes in those at risk. Low-carbohydrate, high-fat diets are advocated as an alternative, but reciprocal increases in dietary fat may have detrimental effects on insulin resistance and offset the benefits of weight reduction. RESEARCH DESIGN AND METHODS We investigated a low-fat (20% fat, 60% carbohydrate) versus a low-carbohydrate (60% fat, 20% carbohydrate) weight reduction diet in 24 overweight/obese subjects ([mean ± SD] BMI 33.6 ± 3.7 kg/m2, aged 39 ± 10 years) in an 8-week randomized controlled trial. All food was weighed and distributed, and intake was calculated to produce a 500 kcal/day energy deficit. Insulin action was assessed by the euglycemic clamp and insulin secretion by meal tolerance test. Body composition, adipokine levels, and vascular compliance by pulse-wave analysis were also measured. RESULTS Significant weight loss occurred in both groups (P < 0.01), with no difference between groups (P = 0.40). Peripheral glucose uptake increased, but there was no difference between groups (P = 0.28), and suppression of endogenous glucose production was also similar between groups. Meal tolerance–related insulin secretion decreased with weight loss with no difference between groups (P = 0.71). The change in overall systemic arterial stiffness was, however, significantly different between diets (P = 0.04); this reflected a significant decrease in augmentation index following the low-fat diet, compared with a nonsignificant increase within the low-carbohydrate group. CONCLUSIONS This study demonstrates comparable effects on insulin resistance of low-fat and low-carbohydrate diets independent of macronutrient content. The difference in augmentation index may imply a negative effect of low-carbohydrate diets on vascular risk. PMID:19720791

Prebiotic stereoselective synthesis of purine and noncanonical pyrimidine nucleotide from nucleobases and phosphorylated carbohydrates.

PubMed

Kim, Hyo-Joong; Benner, Steven A

2017-10-24

According to a current "RNA first" model for the origin of life, RNA emerged in some form on early Earth to become the first biopolymer to support Darwinism here. Threose nucleic acid (TNA) and other polyelectrolytes are also considered as the possible first Darwinian biopolymer(s). This model is being developed by research pursuing a "Discontinuous Synthesis Model" (DSM) for the formation of RNA and/or TNA from precursor molecules that might have been available on early Earth from prebiotic reactions, with the goal of making the model less discontinuous. In general, this is done by examining the reactivity of isolated products from proposed steps that generate those products, with increasing complexity of the reaction mixtures in the proposed mineralogical environments. Here, we report that adenine, diaminopurine, and hypoxanthine nucleoside phosphates and a noncanonical pyrimidine nucleoside (zebularine) phosphate can be formed from the direct coupling reaction of cyclic carbohydrate phosphates with the free nucleobases. The reaction is stereoselective, giving only the β-anomer of the nucleotides within detectable limits. For purines, the coupling is also regioselective, giving the N -9 nucleotide for adenine as a major product. In the DSM, phosphorylated carbohydrates are presumed to have been available via reactions explored previously [Krishnamurthy R, Guntha S, Eschenmoser A (2000) Angew Chem Int Ed 39:2281-2285], while nucleobases are presumed to have been available from hydrogen cyanide and other nitrogenous species formed in Earth's primitive atmosphere. Published under the PNAS license.

Oligomannan Prebiotic Attenuates Immunological, Clinical and Behavioral Symptoms in Mouse Model of Inflammatory Bowel Disease

PubMed Central

Ferenczi, Szilamér; Szegi, Krisztián; Winkler, Zsuzsanna; Barna, Teréz; Kovács, Krisztina J.

2016-01-01

Inflammatory bowel disease shows increasing prevalence, however its pathomechanism and treatment is not fully resolved. Prebiotics are non-digestible carbohydrates which might provide an alternative to treat inflammatory conditions in the gut due to their positive effects either on the microbiome or through their direct effect on macrophages and mucosa. To test the protective effects of an oligomannan prebiotic, yeast cell wall mannooligosaccharide (MOS) was administered in dextran-sulphate-sodium (DSS)-induced mouse model of acute colitis. MOS reduced DSS-induced clinical- (weight loss, diarrhea) and histological scores (mucosal damage) as well as sickness-related anxiety. DSS treatment resulted in changes in colon microbiome with selective increase of Coliform bacteria. MOS administration attenuated colitis-related increase of Coliforms, normalized colonic muc2 expression and attenuated local expression of proinflammatory cytokines IL-1a, IL1b, IL6, KC, G-CSF and MCP1 as well as toll-like receptor TLR4 and NLRP3 inflammasome. Some of the protective effects of MOS were likely be mediated directly through local macrophages because MOS dose-dependently inhibited IL-1b and G-CSF induction following in vitro DSS challenge and IL1a, IL1b, G-SCF-, and IL6 increases after LPS treatment in mouse macrophage cell line RAW264.7. These results highlight oligomannan prebiotics as therapeutic functional food for testing in clinical trials. PMID:27658624

Manufacture of Prebiotics from Biomass Sources

NASA Astrophysics Data System (ADS)

Gullón, Patricia; Gullón, Beatriz; Moure, Andrés; Alonso, José Luis; Domínguez, Herminia; Parajó, Juan Carlos

Biomass from plant material is the most abundant and widespread renewable raw material for sustainable development, and can be employed as a source of polymeric and oligomeric carbohydrates. When ingested as a part of the diet, some biomass polysaccharides and/or their oligomeric hydrolysis products are selectively fermented in the colon, causing prebiotic effects.

Prebiotics from Marine Macroalgae for Human and Animal Health Applications

PubMed Central

O’Sullivan, Laurie; Murphy, Brian; McLoughlin, Peter; Duggan, Patrick; Lawlor, Peadar G.; Hughes, Helen; Gardiner, Gillian E.

2010-01-01

The marine environment is an untapped source of bioactive compounds. Specifically, marine macroalgae (seaweeds) are rich in polysaccharides that could potentially be exploited as prebiotic functional ingredients for both human and animal health applications. Prebiotics are non-digestible, selectively fermented compounds that stimulate the growth and/or activity of beneficial gut microbiota which, in turn, confer health benefits on the host. This review will introduce the concept and potential applications of prebiotics, followed by an outline of the chemistry of seaweed polysaccharides. Their potential for use as prebiotics for both humans and animals will be highlighted by reviewing data from both in vitro and in vivo studies conducted to date. PMID:20714423

Effect of evening exposure to dim or bright light on the digestion of carbohydrate in the supper meal.

PubMed

Hirota, Naoko; Sone, Yoshiaki; Tokura, Hiromi

2003-09-01

In a previous study we found that daytime exposure to bright as compared to dim light exerted a beneficial effect on the digestion of the evening meal. This finding prompted us to examine whether the digestion of the evening meal is also affected by evening light intensity. Subjects lived in light of 200 lux during the daytime (08:00-17:00 h) and took their evening meal at 17:00 h under 20 lux (evening dim-light condition: 17:00-02:00 h) or 2000 lux (evening bright-light condition: 17:00-02:00 h) until retiring at 02:00 h. Assessment of carbohydrate digestion of the evening meal was accomplished by a breath hydrogen test that is indicative of the malabsorption of dietary carbohydrate. Hydrogen excretion in the breath in the evening under the dim-light condition was significantly less than under the bright-light condition (p < 0.05). This finding is the opposite to that obtained in previous experiments in which subjects were exposed to the different intensities of light during the daytime, and indicates that the exposure to dim light in the evening exerts a better effect on carbohydrate digestion in the evening meal than does the exposure to bright light.

Quantification of prebiotics in commercial infant formulas.

PubMed

Sabater, Carlos; Prodanov, Marin; Olano, Agustín; Corzo, Nieves; Montilla, Antonia

2016-03-01

Since breastfeeding is not always possible, infant formulas (IFs) are supplemented with prebiotic oligosaccharides, such as galactooligosaccharides (GOS) and/or fructooligosaccharides (FOS) to exert similar effects to those of the breast milk. Nowadays, a great number of infant formulas enriched with prebiotics are disposal in the market, however there are scarce data about their composition. In this study, the combined use of two chromatographic methods (GC-FID and HPLC-RID) for the quantification of carbohydrates present in commercial infant formulas have been used. According to the results obtained by GC-FID for products containing prebiotics, the content of FOS, GOS and GOS/FOS was in the ranges of 1.6-5.0, 1.7-3.2, and 0.08-0.25/2.3-3.8g/100g of product, respectively. HPLC-RID analysis allowed quantification of maltodextrins with degree of polymerization (DP) up to 19. The methodology proposed here may be used for routine quality control of infant formula and other food ingredients containing prebiotics. Copyright © 2015 Elsevier Ltd. All rights reserved.

Slowly Digestible Carbohydrate for Balanced Energy: In Vitro and In Vivo Evidence

PubMed Central

Gourineni, Vishnupriya; Stewart, Maria L.; Skorge, Rob; Sekula, Bernard C.

2017-01-01

There is growing interest among consumers in foods for sustained energy management, and an increasing number of ingredients are emerging to address this demand. The SUSTRA™ 2434 slowly digestible carbohydrate is a blend of tapioca flour and corn starch, with the potential to provide balanced energy after a meal. The aim of the study was to characterize this starch’s digestion profile in vitro (modified Englyst assay) and in vivo (intact and cecectomized rooster study), and to determine its effects on available energy, by measuring post-prandial glycemia in healthy adults (n = 14), in a randomized, double-blind, placebo-controlled, cross-over study, with two food forms: cold-pressed bar and pudding. The in vitro starch digestion yielded a high slowly digestible fraction (51%) compared to maltodextrin (9%). In the rooster digestibility model, the starch was highly digestible (94%). Consumption of slowly digestible starch (SDS), in an instant pudding or bar, yielded a significantly lower glycemic index compared to a control. At individual time points, the SDS bar and pudding yielded blood glucose levels with significantly lower values at 30–60 min and significantly higher values at 120–240 min, demonstrating a balanced energy release. This is the first study to comprehensively characterize the physiological responses to slowly digestible starch (tapioca and corn blend) in in vitro and in vivo studies. PMID:29125542

Effects of Low-Carbohydrate and Low-Fat Diets

PubMed Central

Bazzano, Lydia A.; Hu, Tian; Reynolds, Kristi; Yao, Lu; Bunol, Calynn; Liu, Yanxi; Chen, Chung-Shiuan; Klag, Michael J.; Whelton, Paul K.; He, Jiang

2015-01-01

Background Low-carbohydrate diets are popular for weight loss, but their cardiovascular effects have not been well-studied, particularly in diverse populations. Objective To examine the effects of a low-carbohydrate diet compared with a low-fat diet on body weight and cardiovascular risk factors. Design A randomized, parallel-group trial. (ClinicalTrials.gov: NCT00609271) Setting A large academic medical center. Participants 148 men and women without clinical cardiovascular disease and diabetes. Intervention A low-carbohydrate (<40 g/d) or low-fat diet (<30% fat; <7% saturated fat). Both groups received dietary counseling at regular intervals throughout the trial. Measurements Data on weight, cardiovascular risk factors, and dietary composition were collected at 0, 3, 6, and 12 months. Results Sixty participants (82%) in the low-fat group and 59 (79%) in the low-carbohydrate group completed the intervention. At 12 months, participants on the low-carbohydrate diet had greater decreases in weight (mean difference in change, −3.5 kg [95% CI, −5.6 to −1.4 kg]; P < 0.001), fat mass (mean difference in change, −1.5% [CI, −2.6% to −0.4%]; P = 0.011), ratio of total to high-density lipoprotein (HDL) cholesterol (mean difference in change, −0.44 [CI, −0.71 to −0.16]; P = 0.002), and triglyceride level (mean difference in change, −0.16 mmol/L [−14.1 mg/dL] [CI, −0.31 to −0.01 mmol/L {−27.4 to −0.8 mg/dL}]; P = 0.038) and greater increases in HDL cholesterol level (mean difference in change, 0.18 mmol/L [7.0 mg/dL] [CI, 0.08 to 0.28 mmol/L {3.0 to 11.0 mg/dL}]; P< 0.001) than those on the low-fat diet. Limitation Lack of clinical cardiovascular disease end points. Conclusion The low-carbohydrate diet was more effective for weight loss and cardiovascular risk factor reduction than the low-fat diet. Restricting carbohydrate may be an option for persons seeking to lose weight and reduce cardiovascular risk factors. Primary Funding Source National

One strike against low-carbohydrate diets

USDA-ARS?s Scientific Manuscript database

There is intense controversy over whether low-carbohydrate or low-fat diets are more efficacious for weight management. Using precise methodology, Hall et al. (2015) demonstrated that a low-carbohydrate diet promoted greater fat oxidation than an isocaloric low-fat diet but, in contrast to popular s...

Carbohydrates and Endothelial Function: Is a Low-Carbohydrate Diet or a Low-Glycemic Index Diet Favourable for Vascular Health?

PubMed Central

Jovanovski, Elena; Zurbau, Andreea

2015-01-01

Low-carbohydrate diets have become increasingly popular in both media and clinical research settings. Although they may improve some metabolic markers, their effects on arterial function remain unclear. Endothelial dysfunction is the well-established response to cardiovascular risk factors and a pivotal feature that precedes atherosclerotic diseases. It has been demonstrated that a high carbohydrate-induced hyperglycemia and subsequent oxidative stress acutely worsen the efficacy of the endothelial vasodilatory system. Thus, in theory, a carbohydrate restricted diet may preserve the integrity of the arterial system. This review attempts to provide insight on whether low-carbohydrate diets have a favorable or detrimental impact on vascular function, or it is perhaps the quality of carbohydrate that should direct dietary recommendations. Research to date suggests that diets low in carbohydrate amount may negatively impact vascular endothelial function. Conversely, it appears that maintaining recommended carbohydrate intake with utilization of low glycemic index foods generates a more favorable vascular profile. Understanding these relationships will aid in deciphering the diverging role of modulating quantity and quality of carbohydrates on cardiovascular risk. PMID:25954727

Carbohydrates and endothelial function: is a low-carbohydrate diet or a low-glycemic index diet favourable for vascular health?

PubMed

Jovanovski, Elena; Zurbau, Andreea; Vuksan, Vladimir

2015-04-01

Low-carbohydrate diets have become increasingly popular in both media and clinical research settings. Although they may improve some metabolic markers, their effects on arterial function remain unclear. Endothelial dysfunction is the well-established response to cardiovascular risk factors and a pivotal feature that precedes atherosclerotic diseases. It has been demonstrated that a high carbohydrate-induced hyperglycemia and subsequent oxidative stress acutely worsen the efficacy of the endothelial vasodilatory system. Thus, in theory, a carbohydrate restricted diet may preserve the integrity of the arterial system. This review attempts to provide insight on whether low-carbohydrate diets have a favorable or detrimental impact on vascular function, or it is perhaps the quality of carbohydrate that should direct dietary recommendations. Research to date suggests that diets low in carbohydrate amount may negatively impact vascular endothelial function. Conversely, it appears that maintaining recommended carbohydrate intake with utilization of low glycemic index foods generates a more favorable vascular profile. Understanding these relationships will aid in deciphering the diverging role of modulating quantity and quality of carbohydrates on cardiovascular risk.

Wholeness and primary and secondary food structure effects on in vitro digestion patterns determine nutritionally distinct carbohydrate fractions in cereal foods.

PubMed

Mishra, Suman; Monro, John

2012-12-01

Starchy foods of differing structure, including bakery products, breakfast cereals, pastas, and pulses were digested in vitro. Bakery products and processed breakfast cereals with little resilient structure yielded large amounts of rapidly available carbohydrate (RAC), less slowly digested starch (SDS) and little inaccessible digestible starch (IDS) (70:22:8%). Partially processed grains, such as rolled oats contained an increased proportion of SDS (55:38:7%). Pastas, being dense starch structures digested more gradually to completion by superficial erosion, yielding approximately equal proportions of RAC and SDS but little IDS (43:52:4%). Pulses, which retained their cellular morphology, digested more linearly yielding a lower proportion of RAC, a larger proportion of SDS and more IDS (9:69:22%). Preservation of native "primary" structure, and use of processing to create "secondary" structure, are both means by which wholeness, in the sense of intactness, can be used to influence carbohydrate digestion to make foods of lower glycaemic impact. Copyright © 2012 Elsevier Ltd. All rights reserved.

Clinical Effects of Prebiotics in Pediatric Population.

PubMed

Orel, Rok; Reberšak, Lea Vodušek

2016-12-15

Prebiotics are non-digestible components of food that in a selective manner trigger the expansion of microbes in the gut with valuable effects for the health of the host. In our document, current literature pertaining to the clinical effects of the use of prebiotics for the treatment and prevention of some common pediatric pathology such as infantile colic, constipation, absorption of minerals, weight gain, diarrhea, respiratory infections, and eczema is reviewed. Data was collected through search of the MEDLINE, PubMed, UpToDate, Cochrane Database of Systemic Reviews, and the Cochrane Controlled Trials Register database as well as through references from relevant articles, all until September 2015. However, only the results of publications with adequate methodological quality were included. Prebiotics seem to be very appealing in treatment of many clinical conditions, explicitly in the fight against constipation, poor weight gain in preterm infants, and eczema in atopic children. In contrast to probiotics, the evidence of true clinical efficacy of prebiotics, supported with exact type and dose information are rather sparse, and there are a limited number of randomized controlled trials concerning prebiotics in children, especially beyond the age of infancy. Large well-designed, controlled, confirmatory clinical trials are required, using commercially available products, to help healthcare providers in making an appropriate decision concerning the appropriate use of prebiotics in different conditions.

GUT MICROBIOTA, PREBIOTICS, PROBIOTICS, AND SYNBIOTICS IN MANAGEMENT OF OBESITY AND PREDIABETES: REVIEW OF RANDOMIZED CONTROLLED TRIALS.

PubMed

Barengolts, Elena

2016-10-01

To review the data from randomized controlled trials (RCTs) for the roles of microbiota, pre-, pro- and synbiotics in metabolic conditions (obesity, prediabetes, and diabetes mellitus type 2 [DM2]). Primary literature was reviewed on the topics including RCTs of pre-, pro- and synbiotics use for metabolic disease. Gut bacteria (microbiota) benefit digestion and have multiple other functions. Microbiota could increase harvesting of energy from the food and cause subclinical inflammation seen in metabolic disorders. Diet-related interventions including prebiotics, probiotics, and synbiotics (combining pre-and probiotics) may benefit metabolic conditions. Prebiotics are complex carbohydrates (i.e., dietary fiber). Results of RCTs of prebiotics suggested a neutral effect on body weight, decreased fasting and postprandial glucose, and improved insulin sensitivity and lipid profile. Some inflammation markers were reduced, sometimes substantially (20-30%). RCTs for probiotics demonstrated significant but small effects on body weight (<3%) and metabolic parameters. The effect was seen mostly with fermented milk or yogurt compared to capsule form, consumption for at least 8 weeks, and use of multiple rather than a single bacterial strain. Changes in microbiota were seen at times with both pre- and probiotics. Pickled and fermented foods, particularly vegetables and beans, could serve as a dietary source of pre-, pro-, and synbiotics. These foods showed possible benefits for morbidity and mortality in prospective cohort studies. Pre-, pro-, and synbiotics could prove useful, but further research is needed to clarify their clinical relevance for the prevention and management of metabolic disease. A1c = glycohemoglobin A1c CI = confidence interval CVD = cardiovascular disease GMB = gut (large bowel) microbiota DM2 = diabetes mellitus type 2 HOMA-IR = homeostatic model assessment of insulin resistance LDL = low-density lipoprotein LPS = lipopolysaccharide NAFLD = nonalcoholic

Sterilization in a liquid of a specific starch makes it slowly digestible in vitro and low glycemic in rats.

PubMed

Severijnen, Chantal; Abrahamse, Evan; van der Beek, Eline M; Buco, Amra; van de Heijning, Bert J M; van Laere, Katrien; Bouritius, Hetty

2007-10-01

Diabetics are recommended to eat a balanced diet containing normal amounts of carbohydrates, preferably those with a low glycemic index. For solid foods, this can be achieved by choosing whole-grain, fiber-rich products. For (sterilized) liquid products, such as meal replacers, the choices for carbohydrate sources are restricted due to technological limitations. Starches usually have a high glycemic index after sterilization in liquids, whereas low glycemic sugars and sugar replacers can only be used in limited amounts. Using an in vitro digestion assay, we identified a resistant starch (RS) source [modified high amylose starch (mHAS)] that might enable the production of a sterilized liquid product with a low glycemic index. Heating mHAS for 4-5 min in liquid increased the slowly digestible starch (SDS) fraction at the expense of the RS portion. The effect was temperature dependent and reached its maximum above 120 degrees C. Heating at 130 degrees C significantly reduced the RS fraction from 49 to 22%. The product remained stable for at least several months when stored at 4 degrees C. To investigate whether a higher SDS fraction would result in a lower postprandial glycemic response, the sterilized mHAS solution was compared with rapidly digestible maltodextrin. Male Wistar rats received an i.g. bolus of 2.0 g available carbohydrate/kg body weight. Ingestion of heat-treated mHAS resulted in a significant attenuation of the postprandial plasma glucose and insulin responses compared with maltodextrin. mHAS appears to be a starch source which, after sterilization in a liquid product, acquires slow-release properties. The long-term stability of mHAS solutions indicates that this may provide a suitable carbohydrate source for low glycemic index liquid products for inclusion in a diabetes-specific diet.

Dietary intakes, attitudes toward carbohydrates of postmenopausal women following low carbohydrate diets.

PubMed

Winham, Donna M; Collins, Courtney B; Hutchins, Andrea M

2009-01-01

Middle-aged women have the highest levels of obesity and comprise the largest group of dieters. Few investigators have examined how women apply weight-loss diet principles in an unsupervised setting. Dietary intakes and attitudes toward carbohydrates were examined in women who were self-reported low carbohydrate dieters (SRLCDs); these intakes and attitudes were compared with those of women who were following their normal diet (non-dieters [NDs]). A convenience sample of 29 postmenopausal women aged 45 to 65 was recruited. Data were obtained by interview, questionnaire, and direct anthropometric measurement. Descriptive statistics, chi-square analysis, and analysis of variance were used to compare groups. Although total energy and protein intakes were similar, SRLCDs consumed significantly more fat and less carbohydrate (expressed as a percentage of total energy) and more cholesterol and less fibre than did NDs. Both groups had unfavourable attitudes toward carbohydrates. The SRLCDs ate more fat than recommended. Women who are considering following a low carbohydrate diet need to know the nutritional risks of unbalanced self-designed low carbohydrate diets. Negative attitudes toward carbohydrates were not confined to dieters. Nutrition education is necessary to help consumers understand basic nutrition principles and to be more skeptical of fad diets.

Carbohydrate catabolic diversity of bifidobacteria and lactobacilli of human origin.

PubMed

McLaughlin, Heather P; Motherway, Mary O'Connell; Lakshminarayanan, Bhuvaneswari; Stanton, Catherine; Paul Ross, R; Brulc, Jennifer; Menon, Ravi; O'Toole, Paul W; van Sinderen, Douwe

2015-06-16

Because increased proportions of particular commensal bacteria such as bifidobacteria and lactobacilli have been linked to human health through a variety of mechanisms, there is corresponding interest in identifying carbohydrates that promote growth and metabolic activity of these bacteria. We evaluated the ability of 20 carbohydrates, including several commercially available carbohydrates that are sold as prebiotic ingredients, to support growth of 32 human-derived isolates belonging to the genera Bifidobacterium and Lactobacillus, including those isolated from healthy elderly subjects. In general, bifidobacterial strains were shown to display more diverse carbohydrate utilization profiles compared to the tested Lactobacillus species, with several bifidobacterial strains capable of metabolizing xylo-oligosaccharide (XOS), arabinoxylan, maltodextrin, galactan and carbohydrates containing fructo-oligosaccharide (FOS) components. In contrast, maltodextrin, galactan, arabinogalactan and galactomannan did not support robust growth (≥0.8 OD600 nm) of any of the Lactobacillus strains assessed. Carbohydrate fermentation was variable among strains tested of the same species for both genera. This study advances our knowledge of polysaccharide utilization by human gut commensals, and provides information for the rational design of selective prebiotic food ingredients. Copyright © 2015 Elsevier B.V. All rights reserved.

Evaluation of the Effect of Low Dietary Fermentable Carbohydrate Content on Growth Performance, Nutrient Digestibility, Blood Characteristics, and Meat Quality in Finishing Pigs

PubMed Central

Hong, S. M.; Hwang, J. H.; Kim, I. H.

2012-01-01

A total of 96 pigs (49.23±3.20 kg) were used in an 11 wk growth trial to evaluate the effect of fermentable carbohydrate (FC) content on growth performance, apparent total tract digestibility (ATTD) of nutrient, blood profile, and meat quality. The dietary treatments were: i) negative control (NC), basal diet, ii) positive control (PC), NC+antibiotics (positive control diet with 5 ppm flavomycin), iii) PCL, PC-13% lower FC, and iv) NCL, NC-13% lower FC. The growth performance (average daily gain, average daily feed intake, and gain/feed) didn’t differ among treatments through the whole experiment. These pigs fed the PCL diet had the greater (p<0.05) apparent total tract digestibility (ATTD) of dry matter than those from PC and NC treatment at the end of the experiment. No differences were observed in white blood cell (WBC), red blood cell (RBC), and lymphocyte concentration among different treatments. After the feeding period, meat samples were collected from the pigs at slaughter. The pigs in NCL and PCL treatments had greater (p<0.05) backfat thickness and lower lean percentage. The color value of loin was higher (p<0.05) in NCL treatment compared to PCL treatment. Also, the NCL treatment had higher (p<0.05) marbling value than PC treatment. The drip loss was depressed by PCL and NCL treatment comapared to NC treatments. The water holding capacity (WHC) was higher (p<0.05) in NC and PCL treatment. In conclusion, the low FC can improve digestibility and meat quality of finishing pigs. PMID:25049693

The Influence of Prebiotics on Neurobiology and Behavior.

PubMed

Kao, A C C; Harty, S; Burnet, P W J

2016-01-01

Manipulating the intestinal microbiota for the benefit of the brain is a concept that has become widely acknowledged. Prebiotics are nondigestible nutrients (i.e., fibers, carbohydrates, or various saccharides) that proliferate intrinsic, beneficial gut bacteria, and so provide an alternative strategy for effectively altering the enteric ecosystem, and thence brain function. Rodent studies demonstrating neurobiological changes following prebiotic intake are slowly emerging, and have thus far revealed significant benefits in disease models, including antiinflammatory and neuroprotective actions. There are also compelling data showing the robust and favorable effects of prebiotics on several behavioral paradigms including, anxiety, learning, and memory. At present, studies in humans are limited, though there is strong evidence for prebiotics modulating emotional processes and the neuroendocrine stress response that may underlie the pathophysiology of anxiety. While the mechanistic details linking the enteric microbiota to the central nervous system remain to be elucidated, there are a number of considerations that can guide future studies. These include the modulation of intestinal endocrine systems and inflammatory cascades, as well as direct interaction with the enteric nervous system and gut mucosa. Our knowledge of gut microbiome-brain communication is steadily progressing, and thorough investigations validating the use of prebiotics in the treatment of neuropsychiatric disorders would be highly valued and are encouraged. © 2016 Elsevier Inc. All rights reserved.

Complex carbohydrates as a possible source of high energy to formulate functional feeds.

PubMed

Ochoa, Leonel; Paniagua Michel, José de Jesús; Olmos-Soto, Jorge

2014-01-01

Carbohydrates (CHOs) are the most abundant organic compounds found in living organisms and are a great source of metabolic energy, both for plants and animals. Besides of CHOs great potential to solve animal's energy requirements and diminishing high feed cost, we first must to understand its digestibility and assimilation to avoid several inconvenients. Today, CHOs feed animal inclusions are of great concern about cost-benefits, animal's health status, and environmental pollution. In this chapter, we make a brief description about sugars (DP1-2), oligosaccharides (DP3-9), polysaccharides (DP ≥10), and their essential characteristics to understand the role of marine and terrestrial CHOs in animal nutrition. Subsequently, we talk about basic concepts, CHOs functional benefits, suggestions about their application and successful cases. This information will contribute to produce a new generation of high-quality and energetic functional feed formulations for livestock and aquaculture farms; which must be of low cost, healthy, and environmentally friendly, with the inclusion of prebiotics and probiotics. © 2014 Elsevier Inc. All rights reserved.

Effect of partitioning the nonfiber carbohydrate fraction and neutral detergent fiber method on digestibility of carbohydrates by dairy cows.

PubMed

Tebbe, A W; Faulkner, M J; Weiss, W P

2017-08-01

Many nutrition models rely on summative equations to estimate feed and diet energy concentrations. These models partition feed into nutrient fractions and multiply the fractions by their estimated true digestibility, and the digestible mass provided by each fraction is then summed and converted to an energy value. Nonfiber carbohydrate (NFC) is used in many models. Although it behaves as a nutritionally uniform fraction, it is a heterogeneous mixture of components. To reduce the heterogeneity, we partitioned NFC into starch and residual organic matter (ROM), which is calculated as 100 - CP - LCFA - ash - starch - NDF, where crude protein (CP), long-chain fatty acids (LCFA), ash, starch, and neutral detergent fiber (NDF) are a percentage of DM. However, the true digestibility of ROM is unknown, and because NDF is contaminated with both ash and CP, those components are subtracted twice. The effect of ash and CP contamination of NDF on in vivo digestibility of NDF and ROM was evaluated using data from 2 total-collection digestibility experiments using lactating dairy cows. Digestibility of NDF was greater when it was corrected for ash and CP than without correction. Conversely, ROM apparent digestibility decreased when NDF was corrected for contamination. Although correcting for contamination statistically increased NDF digestibility, the effect was small; the average increase was 3.4%. The decrease in ROM digestibility was 7.4%. True digestibility of ROM is needed to incorporate ROM into summative equations. Data from multiple digestibility experiments (38 diets) using dairy cows were collated, and ROM concentrations were regressed on concentration of digestible ROM (ROM was calculated without adjusting for ash and CP contamination). The estimated true digestibility coefficient of ROM was 0.96 (SE = 0.021), and metabolic fecal ROM was 3.43 g/100 g of dry matter intake (SE = 0.30). Using a smaller data set (7 diets), estimated true digestibility of ROM when calculated

Focus on Nutrition: Cats and carbohydrates: implications for health and disease.

PubMed

Laflammme, Dottie

2010-01-01

It has been suggested that high-carbohydrate diets contribute to the development of feline diabetes and obesity. The evidence does not support this. Healthy cats efficiently digest and metabolize properly processed starches and complex carbohydrates. Dietary carbohydrate can efficiently meet cats' cellular requirement for carbohydrate (glucose), sparing protein that would otherwise be needed for gluconeogenesis. Excess calories, regardless of source, contribute to obesity and obesity-related problems, but low-carbohydrate, high-fat diets pose a greater risk for obesity. The increasing prevalence of feline diabetes appears to be due to obesity and aging rather than to dietary carbohydrates. However, once cats become diabetic, consumption of a high-protein, low-carbohydrate diet may be beneficial.

Energy efficiency of digestible protein, fat and carbohydrate utilisation for growth in rainbow trout and Nile tilapia.

PubMed

Schrama, Johan W; Haidar, Mahmoud N; Geurden, Inge; Heinsbroek, Leon T N; Kaushik, Sachi J

2018-04-01

Currently, energy evaluation of fish feeds is performed on a digestible energy basis. In contrast to net energy (NE) evaluation systems, digestible energy evaluation systems do not differentiate between the different types of digested nutrients regarding their potential for growth. The aim was to develop an NE evaluation for fish by estimating the energy efficiency of digestible nutrients (protein, fat and carbohydrates) and to assess whether these efficiencies differed between Nile tilapia and rainbow trout. Two data sets were constructed. The tilapia and rainbow data set contained, respectively, eight and nine experiments in which the digestibility of protein, fat and energy and the complete energy balances for twenty-three and forty-five diets was measured. The digestible protein (dCP), digestible fat (dFat) and digestible carbohydrate intakes (dCarb) were calculated. By multiple regression analysis, retained energy (RE) was related to dCP, dFat and dCarb. In tilapia, all digestible nutrients were linearly related to RE (P<0·001). In trout, RE was quadratically related to dCarb (P<0·01) and linearly to dCP and dFat (P<0·001). The NE formula was NE=11·5×dCP+35·8×dFAT+11·3×dCarb for tilapia and NE=13·5×dCP+33·0×dFAT+34·0×dCarb-3·64×(dCarb)2 for trout (NE in kJ/(kg0·8×d); dCP, dFat and dCarb in g/(kg0·8×d)). In tilapia, the energetic efficiency of dCP, dFat and dCarb was 49, 91 and 66 %, respectively, showing large similarity with pigs. Tilapia and trout had similar energy efficiencies of dCP (49 v. 57 %) and dFat (91 v. 84 %), but differed regarding dCarb.

Digestion, absorption, and fermentation of carbohydrates in the newborn.

PubMed

Kien, C L

1996-06-01

In the newborn, sugars present in human milk and formulas are assimilated by both small intestinal digestion and, especially in the case of lactose, colonic bacterial fermentation. Colonic fermentation of carbohydrate serves three major functions: (1) conservation of a fraction of the metabolizable energy of dietary carbohydrate that is not absorbed in the small intestine; (2) prevention of osmotic diarrhea; and (3) production of short-chain fatty acids that stimulate sodium and water absorption, serve as fuel for colonocytes, and stimulate cell replication in colon and small intestine. Diarrhea produced in association with small bowel malabsorption of sugar may be caused by three, potentially overlapping mechanisms: (1) osmotic effects of unfermented sugar, which may cause secondary disruption of fermentation by purging the bacteria or diluting the bacteria mass; (2) damage to the colon mucosa from excessive fermentation leading to SCFA malabsorption and osmotic diarrhea on this basis; and (3) excessive fermentation leading to lowering of luminal pH and inhibition of bacterial enzymes. Therapy aimed at reducing diarrhea associated with sugar malabsorption might involve either slowing of motility to facilitate fermentation or stimulation of fermentative activity, but such interventions would depend on greater understanding of the mechanisms for colonic dysfunction in this condition.

[Specific problems posed by carbohydrate utilization in the rainbow trout].

PubMed

Bergot, F

1979-01-01

Carbohydrate incorporation in trout diets arises problems both at digestive and metabolic levels. Digestive utilization of carbohydrate closely depends on their molecular weight. In addition, in the case of complex carbohydrates (starches), different factors such as the level of incorporation, the amount consumed and the physical state of starch influence the digestibility. The measurement of digestibility in itself is confronted with methodological difficulties. The way the feces are collected can affect the digestion coefficient. Dietary carbohydrates actually serve as a source of energy. Nevertheless, above a certain level in the diet, intolerance phenomena may appear. The question that arises now is to establish the optimal part that carbohydrates can take in the metabolizable energy of a given diet.

Food preferences and weight change during low-fat and low-carbohydrate diets

PubMed Central

McVay, Megan A.; Voils, Corrine I.; Geiselman, Paula J.; Smith, Valerie A.; Coffman, Cynthia J.; Mayer, Stephanie; Yancy, William S.

2016-01-01

Understanding associations between food preferences and weight loss during various effective diets could inform efforts to personalize dietary recommendations and provide insight into weight loss mechanisms. We conducted a secondary analysis of data from a clinical trial in which participants were randomized to either a ‘choice’ arm, in which they were allowed to select between a low-fat diet (n=44) or low-carbohydrate diet (n=61), or to a ‘no choice’ arm, in which they were randomly assigned to a low-fat diet (n=49) or low-carbohydrate diet (n=53). All participants were provided 48 weeks of lifestyle counseling. Food preferences were measured at baseline and every 12 weeks thereafter with the Geiselman Food Preference Questionnaire. Participants were 73% male and 51% African American, with a mean age of 55. Baseline food preferences, including congruency of food preferences with diet, were not associated with weight outcomes. In the low-fat diet group, no associations were found between changes in food preferences and weight over time. In the low-carbohydrate diet group, increased preference for low-carbohydrate diet congruent foods from baseline to 12 weeks was associated with weight loss from 12 to 24 weeks. Additionally, weight loss from baseline to 12 weeks was associated with increased preference for low-carbohydrate diet congruent foods from 12 to 24 weeks. Results suggest that basing selection of low-carbohydrate diet or low-fat diet on food preferences is unlikely to influence weight loss. Congruency of food preferences and weight loss may influence each other early during a low-carbohydrate diet but not low-fat diet, possibly due to different features of these diets. PMID:27133551

Perceived hunger is lower and weight loss is greater in overweight premenopausal women consuming a low-carbohydrate/high-protein vs high-carbohydrate/low-fat diet.

PubMed

Nickols-Richardson, Sharon M; Coleman, Mary Dean; Volpe, Joanne J; Hosig, Kathy W

2005-09-01

The impact of a low-carbohydrate/high-protein diet compared with a high-carbohydrate/low-fat diet on ratings of hunger and cognitive eating restraint were examined. Overweight premenopausal women consumed a low-carbohydrate/high-protein (n=13) or high-carbohydrate/low-fat diet (n=15) for 6 weeks. Fasting body weight (BW) was measured and the Eating Inventory was completed at baseline, weeks 1 to 4, and week 6. All women experienced a reduction in BW (P<.01), although relative BW loss was greater in the low-carbohydrate/high-protein vs high-carbohydrate/low-fat group at week 6 (P<.05). Based on Eating Inventory scores, self-rated hunger decreased (P<.03) in women in the low-carbohydrate/high-protein but not in the high-carbohydrate/low-fat group from baseline to week 6. In both groups, self-rated cognitive eating restraint increased (P<.01) from baseline to week 1 and remained constant to week 6. Both diet groups reported increased cognitive eating restraint, facilitating short-term weight loss; however, the decrease in hunger perception in the low-carbohydrate/high-protein group may have contributed to a greater percentage of BW loss.

Dietary non-digestible carbohydrates promote L-cell differentiation in the proximal colon of rats.

PubMed

Cani, Patrice D; Hoste, Sophie; Guiot, Yves; Delzenne, Nathalie M

2007-07-01

One of the challenges in type 2 diabetes treatment is to ensure pancreas functionality with gut peptides such as glucagon-like peptide-1 (GLP-1). We have recently shown that the endogenous GLP-1 production is promoted by dietary non-digestible carbohydrates (oligofructose), the higher GLP-1 secretion could participate in the control of obesity and associated disorders. This experimental study was designed to highlight the mechanisms of endogenous increase of GLP-1 following non-digestible carbohydrate feeding. Male Wistar rats were fed a standard diet (70.4 g/100 g total carbohydrates; controls) or the same diet supplemented with oligofructose (10 g/100 g diet) for 4 weeks. GLP-1-producing L-cells of the colon were quantified by immunohistochemistry. GLP-1 was quantified by ELISA, and proglucagon, neurogenin 3 and NeuroD mRNA were measured in the colon by quantitative RT-PCR. The number of GLP-1-expressing cells was doubled in the proximal colon of oligofructose-treated rats, a phenomenon correlated with the increase in proglucagon mRNA and peptide content in the tissue. Moreover, oligofructose increased the number of enteroendocrine L-cells in the proximal colon by a mechanism involving up-regulation of two differentiation factors: neurogenin 3 and NeuroD. It is the first demonstration that nutrients fermented in the gut may promote L-cell differentiation in the proximal colon, a phenomenon contributing to a higher endogenous GLP-1 production. These results suggest a new mechanism by which dietary fibres may lower food intake and fat mass development.

Nutritional Evaluation of Young Bulls on Tropical Pasture Receiving Supplements with Different Protein:Carbohydrate Ratios

PubMed Central

Valente, E. E. L.; Paulino, M. F.; Barros, L. V.; Almeida, D. M.; Martins, L. S.; Cabral, C. H. A.

2014-01-01

The objective of this work was to evaluate the nutritional parameters of young bulls supplemented with different ratios of protein: carbohydrate on tropical pastures from 4 until 18 months old. Fifty-five non-castrated beef calves (138.3±3.4 kg, 90 to 150 d of age) were used. The calves (young bulls) were subjected to a 430-d experimental period encompassing 4 seasons. The treatments were as follows: control, only mineral mixture; HPHC, high protein and high carbohydrate supplement; HPLC, high protein and low carbohydrate supplement; LPHC, low protein and high carbohydrate supplement; and LPLC, low protein and low carbohydrate supplement. The amount of supplement was adjusted every 28 d. Dry matter (DM) intake was higher in the dry-to-rainy transition and rainy seasons for all nutritional plans. Non-supplemented animals had lower intakes of DM and total digestible nutrients (TDN) than supplemented young bulls in all seasons. Although differences in DM intake were not observed between supplemented animals, the supplements with high carbohydrate (HPHC and LPHC) had lower forage intake during suckling (rainy-to-dry transition season) and in the rainy season. However, the HPHC treatment animals had higher intake and digestibility of neutral detergent fiber. It can be concluded that supplementation with high protein levels (supplying 50% of the crude protein requirement) provide the best nutritional parameters for grazing young bulls in most seasons, increasing intake and digestibility of diet, and these effects are more intense when associated with high carbohydrate levels level (supplying 30% TDN requirement). PMID:25178297

Biopolymer-prebiotic carbohydrate blends and their effects on the retention of bioactive compounds and maintenance of antioxidant activity.

PubMed

Silva, Eric Keven; Zabot, Giovani L; Cazarin, Cinthia B B; Maróstica, Mário R; Meireles, M Angela A

2016-06-25

The objective of this study was to evaluate the use of inulin (IN), a prebiotic carbohydrate without superficial activity, as an encapsulating matrix of lipophilic bioactive compounds. For achieving the encapsulation, IN was associated with biopolymers that present superficial activity: modified starch (HiCap), whey protein isolate (WPI) and gum acacia (GA). Encapsulation was performed through emulsification assisted by ultrasound followed by freeze-drying (FD) process to dry the emulsions. All blends retained geranylgeraniol. GA-IN blend yielded the highest geranylgeraniol retention (96±2wt.%) and entrapment efficiency (94±3wt.%), whilst WPI-IN blend yielded the highest encapsulation efficiency (88±2wt.%). After encapsulation, composition of geranylgeraniol in the annatto seed oil was maintained (23.0±0.5g/100g of oil). Such findings indicate that the method of encapsulation preserved the active compound. All blends were also effective for maintaining the antioxidant activity of the oil through ORAC and DPPH analyses. Copyright © 2016 Elsevier Ltd. All rights reserved.

Potential Health Benefits of Combining Yogurt and Fruits Based on Their Probiotic and Prebiotic Properties.

PubMed

Fernandez, Melissa Anne; Marette, André

2017-01-01

Fruit and yogurt have been identified individually as indicators of healthy dietary patterns. Fruits are relatively low in energy density and are an excellent source of antioxidants and prebiotic fibers and polyphenols, which can promote digestive health. Yogurt, on the other hand, is a nutrient-dense food that is a good source of dairy protein, calcium, magnesium, vitamin B-12, conjugated linoleic acid, and other key fatty acids. In addition, it contains beneficial bacterial cultures, making it a potential source of probiotics. Yogurt's unique fermented food matrix provides added health benefits by enhancing nutrient absorption and digestion. Combining the intake of yogurt and fruit could provide probiotics, prebiotics, high-quality protein, important fatty acids, and a mixture of vitamins and minerals that have the potential to exert synergistic effects on health. Yogurt consumption has been associated with reduced weight gain and a lower incidence of type 2 diabetes, whereas fruits have established effects on reducing the risk of cardiovascular disease. Yogurt and fruits can be eaten together and may exert combined health benefits through potential prebiotic and probiotic effects. Furthermore, substituting high-energy, nutrient-deficient snacks with fruit and yogurt could reduce the intake of high-calorie obesogenic foods. In light of the positive cardiometabolic impacts of fruit and yogurt and their association with healthy dietary patterns, there is sufficient evidence to warrant further exploration into the potential synergistic health benefits of a combined intake of fruit and yogurt. © 2017 American Society for Nutrition.

Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet.

PubMed

Shai, Iris; Schwarzfuchs, Dan; Henkin, Yaakov; Shahar, Danit R; Witkow, Shula; Greenberg, Ilana; Golan, Rachel; Fraser, Drora; Bolotin, Arkady; Vardi, Hilel; Tangi-Rozental, Osnat; Zuk-Ramot, Rachel; Sarusi, Benjamin; Brickner, Dov; Schwartz, Ziva; Sheiner, Einat; Marko, Rachel; Katorza, Esther; Thiery, Joachim; Fiedler, Georg Martin; Blüher, Matthias; Stumvoll, Michael; Stampfer, Meir J

2008-07-17

Trials comparing the effectiveness and safety of weight-loss diets are frequently limited by short follow-up times and high dropout rates. In this 2-year trial, we randomly assigned 322 moderately obese subjects (mean age, 52 years; mean body-mass index [the weight in kilograms divided by the square of the height in meters], 31; male sex, 86%) to one of three diets: low-fat, restricted-calorie; Mediterranean, restricted-calorie; or low-carbohydrate, non-restricted-calorie. The rate of adherence to a study diet was 95.4% at 1 year and 84.6% at 2 years. The Mediterranean-diet group consumed the largest amounts of dietary fiber and had the highest ratio of monounsaturated to saturated fat (P<0.05 for all comparisons among treatment groups). The low-carbohydrate group consumed the smallest amount of carbohydrates and the largest amounts of fat, protein, and cholesterol and had the highest percentage of participants with detectable urinary ketones (P<0.05 for all comparisons among treatment groups). The mean weight loss was 2.9 kg for the low-fat group, 4.4 kg for the Mediterranean-diet group, and 4.7 kg for the low-carbohydrate group (P<0.001 for the interaction between diet group and time); among the 272 participants who completed the intervention, the mean weight losses were 3.3 kg, 4.6 kg, and 5.5 kg, respectively. The relative reduction in the ratio of total cholesterol to high-density lipoprotein cholesterol was 20% in the low-carbohydrate group and 12% in the low-fat group (P=0.01). Among the 36 subjects with diabetes, changes in fasting plasma glucose and insulin levels were more favorable among those assigned to the Mediterranean diet than among those assigned to the low-fat diet (P<0.001 for the interaction among diabetes and Mediterranean diet and time with respect to fasting glucose levels). Mediterranean and low-carbohydrate diets may be effective alternatives to low-fat diets. The more favorable effects on lipids (with the low-carbohydrate diet) and on

The role of condensed tannins in the nutritional value of Lotus pedunculatus for sheep. 4. Sites of carbohydrate and protein digestion as influenced by dietary reactive tannin concentration.

PubMed

Barry, T N; Manley, T R; Duncan, S J

1986-01-01

1. Vegetative secondary growth Lotus pedunculatus was cut daily, and fed fresh at hourly intervals (600 g dry matter (DM)/d) to three groups each of three sheep fitted with permanent cannulas into the rumen and duodenum. Lotus fed to two of the groups was sprayed with low and high rates of polyethylene glycol (PEG; molecular weight 3350), which specifically binds the condensed tannins (CT). Nutrient intake and faecal excretion were measured directly, duodenal flows estimated from continuous intraruminal infusion of inert ruthenium phenanthroline (Ru-P) and CrEDTA markers, and rumen pool sizes measured at slaughter. 2. Dietary concentrations of total reactive CT (i.e. that not bound to PEG) were 95, 45 and 14 g/kg DM, whilst the corresponding values for free CT were 15, 5 and 2 g/kg DM. 3. Increasing dietary reactive CT concentration linearly increased duodenal flows of non-ammonia nitrogen, but linearly decreased the apparent digestibility of energy and organic matter, and rumen digestion of hemicellulose but not of cellulose. Rumen digestion as a proportion of total digestion was increased by the higher PEG rate for organic matter, energy, pectin and lignin. 4. High dietary CT concentration was associated with increased N retention. Rumen ammonia concentration and pool size showed only a slight decline on this diet, indicating that there must have been increased recycling of N into the rumen. 5. Increasing dietary reactive CT concentration had no effect on the rate at which carbohydrate constituents were degraded in the rumen per unit time (FDR), but increased the rate at which their undegraded residues (FOR) left the rumen per unit time. The latter appeared to be the principal mechanism by which rumen digestion as a proportion of total digestion was reduced at high dietary CT concentrations. From a comparison of FDR and FOR of carbohydrate components in lotus and Brassica oleracea diets, it was concluded that hemicellulose digestion was rate-limiting for rumen

Flux analysis of the human proximal colon using anaerobic digestion model 1.

PubMed

Motelica-Wagenaar, Anne Marieke; Nauta, Arjen; van den Heuvel, Ellen G H M; Kleerebezem, Robbert

2014-08-01

The colon can be regarded as an anaerobic digestive compartment within the gastro intestinal tract (GIT). An in silico model simulating the fluxes in the human proximal colon was developed on basis of the anaerobic digestion model 1 (ADM1), which is traditionally used to model waste conversion to biogas. Model calibration was conducted using data from in vitro fermentation of the proximal colon (TIM-2), and, amongst others, supplemented with the bio kinetics of prebiotic galactooligosaccharides (GOS) fermentation. The impact of water and solutes absorption by the host was also included. Hydrolysis constants of carbohydrates and proteins were estimated based on total short chain fatty acids (SCFA) and ammonia production in vitro. Model validation was established using an independent dataset of a different in vitro model: an in vitro three-stage continuous culture system. The in silico model was shown to provide quantitative insight in the microbial community structure in terms of functional groups, and the substrate and product fluxes between these groups as well as the host, as a function of the substrate composition, pH and the solids residence time (SRT). The model confirms the experimental observation that methanogens are washed out at low pH or low SRT-values. The in silico model is proposed as useful tool in the design of experimental setups for in vitro experiments by giving insight in fermentation processes in the proximal human colon. Copyright © 2014. Published by Elsevier Ltd.

Health Effects of Low-Carbohydrate Diets: Where Should New Research Go?

PubMed Central

Wylie-Rosett, Judith; Aebersold, Karin; Conlon, Beth; Isasi, Carmen R.; Ostrovsky, Natania W.

2013-01-01

There has been considerable debate about the metabolic effects of restricting carbohydrate intake in weight and diabetes management. However, the American Diabetes Association has noted that weight and metabolic improvements can be achieved with low carbohydrate, low fat (implicitly higher carbohydrate), or a Mediterranean style diet (usually an intermediate level of carbohydrate). Our paper addresses variability in the definition for low or restricted carbohydrate, the effects of carbohydrate restriction on diabetes-related health outcomes, strategies for restricting carbohydrate intake, and potential genetic variability in response to dietary carbohydrate restriction. Issues for future research are also addressed. PMID:23266565

High Antioxidant Action and Prebiotic Activity of Hydrolyzed Spent Coffee Grounds (HSCG) in a Simulated Digestion-Fermentation Model: Toward the Development of a Novel Food Supplement.

PubMed

Panzella, Lucia; Pérez-Burillo, Sergio; Pastoriza, Silvia; Martín, María Ángeles; Cerruti, Pierfrancesco; Goya, Luis; Ramos, Sonia; Rufián-Henares, José Ángel; Napolitano, Alessandra; d'Ischia, Marco

2017-08-09

Spent coffee grounds are a byproduct with a large production all over the world. The aim of this study was to explore the effects of a simulated digestion-fermentation treatment on hydrolyzed spent coffee grounds (HSCG) and to investigate the antioxidant properties of the digestion and fermentation products in the human hepatocellular carcinoma HepG2 cell line. The potentially bioaccessible (soluble) fractions exhibited high chemoprotective activity in HepG2 cells against oxidative stress. Structural analysis of both the indigestible (insoluble) and soluble material revealed partial hydrolysis and release of the lignin components in the potentially bioaccessible fraction following simulated digestion-fermentation. A high prebiotic activity as determined from the increase in Lactobacillus spp. and Bifidobacterium spp. and the production of short-chain fatty acids (SCFAs) following microbial fermentation of HSCG was also observed. These results pave the way toward the use of HSCG as a food supplement.

Potential Health Benefits of Combining Yogurt and Fruits Based on Their Probiotic and Prebiotic Properties123

PubMed Central

2017-01-01

Fruit and yogurt have been identified individually as indicators of healthy dietary patterns. Fruits are relatively low in energy density and are an excellent source of antioxidants and prebiotic fibers and polyphenols, which can promote digestive health. Yogurt, on the other hand, is a nutrient-dense food that is a good source of dairy protein, calcium, magnesium, vitamin B-12, conjugated linoleic acid, and other key fatty acids. In addition, it contains beneficial bacterial cultures, making it a potential source of probiotics. Yogurt’s unique fermented food matrix provides added health benefits by enhancing nutrient absorption and digestion. Combining the intake of yogurt and fruit could provide probiotics, prebiotics, high-quality protein, important fatty acids, and a mixture of vitamins and minerals that have the potential to exert synergistic effects on health. Yogurt consumption has been associated with reduced weight gain and a lower incidence of type 2 diabetes, whereas fruits have established effects on reducing the risk of cardiovascular disease. Yogurt and fruits can be eaten together and may exert combined health benefits through potential prebiotic and probiotic effects. Furthermore, substituting high-energy, nutrient-deficient snacks with fruit and yogurt could reduce the intake of high-calorie obesogenic foods. In light of the positive cardiometabolic impacts of fruit and yogurt and their association with healthy dietary patterns, there is sufficient evidence to warrant further exploration into the potential synergistic health benefits of a combined intake of fruit and yogurt. PMID:28096139

Probiotics, prebiotics and child health: where are we going?

PubMed

Salvini, F; Granieri, L; Gemmellaro, L; Giovannini, M

2004-01-01

Changes in gastrointestinal (GI) bacteria caused by diet, antibiotics or other factors could alter enteric and systemic immune functions; changing the gut microflora composition by diet supplementation with specific live microbiota (probiotics) may be beneficial. The 'natural' target of ingested probiotics is the intestine, its microflora and associated immune system. Most published data concern use of probiotics to prevent and treat GI infections. Evidence for possible beneficial effects on mucosal barrier dysfunctions, including food allergy, inflammatory bowel disease, and respiratory and urinary tract infections, is emerging. The role of prebiotics (non-digestible oligosaccharides that reduce the growth or virulence of pathogens and induce systemic effects) is being investigated. Preliminary studies indicate that prebiotics may be useful dietary adjuncts for managing GI infections. Prebiotic and probiotic use in infants is attempting to modify a complex microbial ecosystem. Better understanding of the long-term effects of these interventions on infant gut microflora is an important goal.

Characteristics of Metroxylon sagu resistant starch type III as prebiotic substance.

PubMed

Zi-Ni, Tan; Rosma, Ahmad; Napisah, Hussin; Karim, Alias A; Liong, Min-Tze

2015-04-01

Resistant starch type III (RS3 ) was produced from sago (Metroxylon sagu) and evaluated for its characteristics as a prebiotic. Two RS3 samples designated sago RS and HCl-sago RS contained 35.71% and 68.30% RS, respectively, were subjected to hydrolyses by gastric juice and digestive enzymes and to absorption. Both sago RS and HCl-sago RS were resistant to 180 min hydrolysis by gastric acidity at pH 1 to 4 with less than 0.85% hydrolyzed. Both samples were also resistant toward hydrolysis by gastrointestinal tract enzymes and intestinal absorption with 96.75% and 98.69% of RS3 were recovered respectively after 3.5 h digestion and overnight dialysis at 37 °C. Sago RS3 supported the growth of both beneficial (lactobacilli and Bifidobacteria) and pathogenic microbes (Escherichia coli, Campylobacter coli, and Clostridium perfringens) in the range of 2.60 to 3.91 log10 CFU/mL. Hence, prebiotic activity score was applied to describe the extent to which sago RS3 supports selective growth of the lactobacilli and bifidobacteria strains over pathogenic bacteria. The highest scores were obtained from Bifidobacterium sp. FTDC8943 grown on sago RS (+0.26) and HCl-sago RS (+0.24) followed by L. bulgaricus FTDC1511 grown on sago RS (+0.21). The findings had suggested that sago RS3 has the prebiotic partial characteristics and it is suggested to further assess the suitability of sago RS3 as a prebiotic material. © 2015 Institute of Food Technologists®

Microbial Populations in Naked Neck Chicken Ceca Raised on Pasture Flock Fed with Commercial Yeast Cell Wall Prebiotics via an Illumina MiSeq Platform

PubMed Central

Park, Si Hong; Lee, Sang In; Ricke, Steven C.

2016-01-01

Prebiotics are non-digestible carbohydrate dietary supplements that selectively stimulate the growth of one or more beneficial bacteria in the gastrointestinal tract of the host. These bacteria can inhibit colonization of pathogenic bacteria by producing antimicrobial substances such as short chain fatty acids (SCFAs) and competing for niches with pathogens within the gut. Pasture flock chickens are generally raised outdoors with fresh grass, sunlight and air, which represents different environmental growth conditions compared to conventionally raised chickens. The purpose of this study was to evaluate the difference in microbial populations from naked neck chicken ceca fed with commercial prebiotics derived from brewer’s yeast cell wall via an Illumina MiSeq platform. A total of 147 day-of-hatch naked neck chickens were distributed into 3 groups consisted of 1) C: control (no prebiotic), 2) T1: Biolex® MB40 with 0.2%, and 3) T2: Leiber® ExCel with 0.2%, consistently supplemented prebiotics during the experimental period. At 8 weeks, a total of 15 birds from each group were randomly selected and ceca removed for DNA extraction. The Illumina Miseq platform based on V4 region of 16S rRNA gene was applied for microbiome analysis. Both treatments exhibited limited impact on the microbial populations at the phylum level, with no significant differences in the OTU number of Bacteroidetes among groups and an increase of Proteobacteria OTUs for the T1 (Biolex® MB40) group. In addition there was a significant increase of genus Faecalibacterium OTU, phylum Firmicutes. According to the development of next generation sequencing (NGS), microbiome analysis based on 16S rRNA gene proved to be informative on the prebiotic impact on poultry gut microbiota in pasture-raised naked neck birds. PMID:26992104

Microbial Populations in Naked Neck Chicken Ceca Raised on Pasture Flock Fed with Commercial Yeast Cell Wall Prebiotics via an Illumina MiSeq Platform.

PubMed

Park, Si Hong; Lee, Sang In; Ricke, Steven C

2016-01-01

Prebiotics are non-digestible carbohydrate dietary supplements that selectively stimulate the growth of one or more beneficial bacteria in the gastrointestinal tract of the host. These bacteria can inhibit colonization of pathogenic bacteria by producing antimicrobial substances such as short chain fatty acids (SCFAs) and competing for niches with pathogens within the gut. Pasture flock chickens are generally raised outdoors with fresh grass, sunlight and air, which represents different environmental growth conditions compared to conventionally raised chickens. The purpose of this study was to evaluate the difference in microbial populations from naked neck chicken ceca fed with commercial prebiotics derived from brewer's yeast cell wall via an Illumina MiSeq platform. A total of 147 day-of-hatch naked neck chickens were distributed into 3 groups consisted of 1) C: control (no prebiotic), 2) T1: Biolex® MB40 with 0.2%, and 3) T2: Leiber® ExCel with 0.2%, consistently supplemented prebiotics during the experimental period. At 8 weeks, a total of 15 birds from each group were randomly selected and ceca removed for DNA extraction. The Illumina Miseq platform based on V4 region of 16S rRNA gene was applied for microbiome analysis. Both treatments exhibited limited impact on the microbial populations at the phylum level, with no significant differences in the OTU number of Bacteroidetes among groups and an increase of Proteobacteria OTUs for the T1 (Biolex® MB40) group. In addition there was a significant increase of genus Faecalibacterium OTU, phylum Firmicutes. According to the development of next generation sequencing (NGS), microbiome analysis based on 16S rRNA gene proved to be informative on the prebiotic impact on poultry gut microbiota in pasture-raised naked neck birds.

Prebiotics: A Potential Treatment Strategy for the Chemotherapy-damaged Gut?

PubMed

Wang, Hanru; Geier, Mark S; Howarth, Gordon S

2016-01-01

Mucositis, characterized by ulcerative lesions along the alimentary tract, is a common consequence of many chemotherapy regimens. Chemotherapy negatively disrupts the intestinal microbiota, resulting in increased numbers of potentially pathogenic bacteria, such as Clostridia and Enterobacteriaceae, and decreased numbers of "beneficial" bacteria, such as Lactobacilli and Bifidobacteria. Agents capable of restoring homeostasis in the bowel microbiota could, therefore, be applicable to mucositis. Prebiotics are indigestible compounds, commonly oligosaccharides, that seek to reverse chemotherapy-induced intestinal dysbiosis through selective colonization of the intestinal microbiota by probiotic bacteria. In addition, evidence is emerging that certain prebiotics contribute to nutrient digestibility and absorption, modulate intestinal barrier function through effects on mucin expression, and also modify mucosal immune responses, possibly via inflammasome-mediated processes. This review examines the known mechanisms of prebiotic action, and explores their potential for reducing the severity of chemotherapy-induced mucositis in the intestine.

Prebiotic inulin: Useful dietary adjuncts to manipulate the livestock gut microflora

PubMed Central

Samanta, A.K.; Jayapal, Natasha; Senani, S.; Kolte, A.P.; Sridhar, Manpal

2013-01-01

In recent years, there has been a growing appreciation on the relevance of gastrointestinal microflora in both ruminants and non-ruminants owing to revelation of their role in several physiological functions including digestion, nutrient utilization, pathogen exclusion, gastrointestinal development, immunity system, gut gene expression and quality of animal products. The ban imposed on the use of antibiotics and hormones in feed has compelled animal researchers in finding an alternative which could overcome the issues of conventional feed additives. Though the concept of prebiotic was evolved keeping in mind the gastrointestinal flora of human beings, presently animal researchers are exploring the efficiency of prebiotic (inulin) for modulating the gut ecosystem of both ruminants and non-ruminants. It was revealed that prebiotic inulin is found to exhibit desirable changes in the gut of non-ruminants like poultry, swine, rabbit etc for augmenting gut health and improvement of product quality. Similarly, in ruminants the prebiotic reduces rumen ammonia nitrogen, methane production, increase microbial protein synthesis and live weight gains in calves. Unlike other feed additives, prebiotic exhibits its effect in multipronged ways for overall increase in the performances of the animals. In coming days, it is expected that prebiotics could be the part of diets in both ruminants and non-ruminants for enabling modulation of gut microflora vis a vis animals productivity in ecological ways. PMID:24159277

Probiotics, Prebiotics and Immunomodulation of Gut Mucosal Defences: Homeostasis and Immunopathology

PubMed Central

Hardy, Holly; Harris, Jennifer; Lyon, Eleanor; Beal, Jane; Foey, Andrew D.

2013-01-01

Probiotics are beneficial microbes that confer a realistic health benefit on the host, which in combination with prebiotics, (indigestible dietary fibre/carbohydrate), also confer a health benefit on the host via products resulting from anaerobic fermentation. There is a growing body of evidence documenting the immune-modulatory ability of probiotic bacteria, it is therefore reasonable to suggest that this is potentiated via a combination of prebiotics and probiotics as a symbiotic mix. The need for probiotic formulations has been appreciated for the health benefits in “topping up your good bacteria” or indeed in an attempt to normalise the dysbiotic microbiota associated with immunopathology. This review will focus on the immunomodulatory role of probiotics and prebiotics on the cells, molecules and immune responses in the gut mucosae, from epithelial barrier to priming of adaptive responses by antigen presenting cells: immune fate decision—tolerance or activation? Modulation of normal homeostatic mechanisms, coupled with findings from probiotic and prebiotic delivery in pathological studies, will highlight the role for these xenobiotics in dysbiosis associated with immunopathology in the context of inflammatory bowel disease, colorectal cancer and hypersensitivity. PMID:23760057

Potential of fructooligosaccharide prebiotics in alternative and nonconventional poultry production systems.

PubMed

Ricke, S C

2015-06-01

Fructooligosaccharide and inulin prebiotics are carbohydrate-based polymers derived from natural sources that can be utilized by certain gastrointestinal tract bacteria but not by the host animal. They are attractive as feed additives for nonconventional poultry production systems because they select for beneficial microorganisms that are thought to promote nutritional benefits to the bird and potentially limit foodborne pathogen establishment. There have been numerous studies conducted with prebiotic supplements to assess their impact in humans, animals, and conventionally raised poultry but only limited research has been conducted with birds grown under nonconventional production conditions. Much remains unknown about the specific mechanism(s) associated with their impact on the host as well as the gastrointestinal tract microflora. Utilization of several recently developed approaches such as microbiome and metabolomic analyses should offer more insight on how dietary prebiotic additives influence the development of the gastrointestinal tract microbiota and these subsequent changes correspond with alterations in a bird's physiology as it matures. As more detailed and precise studies are done with nonconventional poultry, it is likely that structurally distinct prebiotics will influence not only the gastrointestinal tract microbiota differently, but potentially interact directly and/or indirectly with the bird host in distinguishable patterns as well. These functions will be important to delineate if further applications are to be developed for specific prebiotics in nonconventional poultry production systems. © 2015 Poultry Science Association Inc.

A randomized trial of a low-carbohydrate diet for obesity.

PubMed

Foster, Gary D; Wyatt, Holly R; Hill, James O; McGuckin, Brian G; Brill, Carrie; Mohammed, B Selma; Szapary, Philippe O; Rader, Daniel J; Edman, Joel S; Klein, Samuel

2003-05-22

Despite the popularity of the low-carbohydrate, high-protein, high-fat (Atkins) diet, no randomized, controlled trials have evaluated its efficacy. We conducted a one-year, multicenter, controlled trial involving 63 obese men and women who were randomly assigned to either a low-carbohydrate, high-protein, high-fat diet or a low-calorie, high-carbohydrate, low-fat (conventional) diet. Professional contact was minimal to replicate the approach used by most dieters. Subjects on the low-carbohydrate diet had lost more weight than subjects on the conventional diet at 3 months (mean [+/-SD], -6.8+/-5.0 vs. -2.7+/-3.7 percent of body weight; P=0.001) and 6 months (-7.0+/-6.5 vs. -3.2+/-5.6 percent of body weight, P=0.02), but the difference at 12 months was not significant (-4.4+/-6.7 vs. -2.5+/-6.3 percent of body weight, P=0.26). After three months, no significant differences were found between the groups in total or low-density lipoprotein cholesterol concentrations. The increase in high-density lipoprotein cholesterol concentrations and the decrease in triglyceride concentrations were greater among subjects on the low-carbohydrate diet than among those on the conventional diet throughout most of the study. Both diets significantly decreased diastolic blood pressure and the insulin response to an oral glucose load. The low-carbohydrate diet produced a greater weight loss (absolute difference, approximately 4 percent) than did the conventional diet for the first six months, but the differences were not significant at one year. The low-carbohydrate diet was associated with a greater improvement in some risk factors for coronary heart disease. Adherence was poor and attrition was high in both groups. Longer and larger studies are required to determine the long-term safety and efficacy of low-carbohydrate, high-protein, high-fat diets. Copyright 2003 Massachusetts Medical Society

Co-digestion of municipal sewage sludge and solid waste: modelling of carbohydrate, lipid and protein content influence.

PubMed

Nielfa, A; Cano, R; Pérez, A; Fdez-Polanco, M

2015-03-01

Solid wastes from industrial, commercial and community activities are of growing concern as the total volume of waste produced continues to increase. The knowledge of the specific composition and characteristics of the waste is an important tool in the correct development of the anaerobic digestion process. The problems derived from the anaerobic digestion of sole substrates with high lipid, carbohydrate or protein content lead to the co-digestion of these substrates with another disposed waste, such as sewage sludge. The kinetic of the anaerobic digestion is especially difficult to explain adequately, although some mathematical models are able to represent the main aspects of a biological system, thus improving understanding of the parameters involved in the process. The aim of this work is to evaluate the experimental biochemical methane potential on the co-digestion of sewage sludge with different solid wastes (grease; spent grain and cow manure) through the implementation of four kinetic models. The co-digestion of grease waste and mixed sludge obtained the best improvements from the sole substrates, with additional positive synergistic effects. The Gompertz model fits the experimental biochemical methane potential to an accuracy of 99%, showing a correlation between the percentage of lipid in the substrates and co-digestions and the period of lag phase. © The Author(s) 2015.

The case for low carbohydrate diets in diabetes management.

PubMed

Arora, Surender K; McFarlane, Samy I

2005-07-14

A low fat, high carbohydrate diet in combination with regular exercise is the traditional recommendation for treating diabetes. Compliance with these lifestyle modifications is less than satisfactory, however, and a high carbohydrate diet raises postprandial plasma glucose and insulin secretion, thereby increasing risk of CVD, hypertension, dyslipidemia, obesity and diabetes. Moreover, the current epidemic of diabetes and obesity has been, over the past three decades, accompanied by a significant decrease in fat consumption and an increase in carbohydrate consumption. This apparent failure of the traditional diet, from a public health point of view, indicates that alternative dietary approaches are needed. Because carbohydrate is the major secretagogue of insulin, some form of carbohydrate restriction is a prima facie candidate for dietary control of diabetes. Evidence from various randomized controlled trials in recent years has convinced us that such diets are safe and effective, at least in short-term. These data show low carbohydrate diets to be comparable or better than traditional low fat high carbohydrate diets for weight reduction, improvement in the dyslipidemia of diabetes and metabolic syndrome as well as control of blood pressure, postprandial glycemia and insulin secretion. Furthermore, the ability of low carbohydrate diets to reduce triglycerides and to increase HDL is of particular importance. Resistance to such strategies has been due, in part, to equating it with the popular Atkins diet. However, there are many variations and room for individual physician planning. Some form of low carbohydrate diet, in combination with exercise, is a viable option for patients with diabetes. However, the extreme reduction of carbohydrate of popular diets (<30 g/day) cannot be recommended for a diabetic population at this time without further study. On the other hand, the dire objections continually raised in the literature appear to have very little scientific

Evidence supporting oral sensitivity to complex carbohydrates independent of sweet taste sensitivity in humans.

PubMed

Low, Julia Y Q; Lacy, Kathleen E; McBride, Robert L; Keast, Russell S J

2017-01-01

Compared to simple sugars, complex carbohydrates have been assumed invisible to taste. However, two recent studies proposed that there may be a perceivable taste quality elicited by complex carbohydrates independent of sweet taste. There is precedent with behavioural studies demonstrating that rats are very attracted to complex carbohydrates, and that complex carbohydrates are preferred to simple sugars at low concentrations. This suggests that rats may have independent taste sensors for simple sugars and complex carbohydrates. The aim of this paper is to investigate oral sensitivities of two different classes of complex carbohydrates (a soluble digestible and a soluble non-digestible complex carbohydrate), and to compare these to other caloric and non-nutritive sweeteners in addition to the prototypical tastes using two commonly used psychophysical measures. There were strong correlations between the detection thresholds and mean intensity ratings for complex carbohydrates (maltodextrin, oligofructose) (r = 0.94, P < 0.001). There were no significant correlations between the detection thresholds of the complex carbohydrates (maltodextrin, oligofructose) and the sweeteners (glucose, fructose, sucralose, Rebaudioside A, erythritol) (all P > 0.05). However, moderate correlations were observed between perceived intensities of complex carbohydrates and sweeteners (r = 0.48-0.61, P < 0.05). These data provide evidence that complex carbohydrates can be sensed in the oral cavity over a range of concentrations independent of sweet taste sensitivity at low concentrations, but with partial overlap with sweet taste intensity at higher concentrations.

Evidence supporting oral sensitivity to complex carbohydrates independent of sweet taste sensitivity in humans

PubMed Central

Lacy, Kathleen E.; Keast, Russell S. J.

2017-01-01

Compared to simple sugars, complex carbohydrates have been assumed invisible to taste. However, two recent studies proposed that there may be a perceivable taste quality elicited by complex carbohydrates independent of sweet taste. There is precedent with behavioural studies demonstrating that rats are very attracted to complex carbohydrates, and that complex carbohydrates are preferred to simple sugars at low concentrations. This suggests that rats may have independent taste sensors for simple sugars and complex carbohydrates. The aim of this paper is to investigate oral sensitivities of two different classes of complex carbohydrates (a soluble digestible and a soluble non-digestible complex carbohydrate), and to compare these to other caloric and non-nutritive sweeteners in addition to the prototypical tastes using two commonly used psychophysical measures. There were strong correlations between the detection thresholds and mean intensity ratings for complex carbohydrates (maltodextrin, oligofructose) (r = 0.94, P < 0.001). There were no significant correlations between the detection thresholds of the complex carbohydrates (maltodextrin, oligofructose) and the sweeteners (glucose, fructose, sucralose, Rebaudioside A, erythritol) (all P > 0.05). However, moderate correlations were observed between perceived intensities of complex carbohydrates and sweeteners (r = 0.48–0.61, P < 0.05). These data provide evidence that complex carbohydrates can be sensed in the oral cavity over a range of concentrations independent of sweet taste sensitivity at low concentrations, but with partial overlap with sweet taste intensity at higher concentrations. PMID:29281655

Preload of slowly digestible carbohydrate microspheres decreases gastric emptying rate of subsequent meal in humans.

PubMed

Cisse, Fatimata; Pletsch, Elizabeth A; Erickson, Daniel P; Chegeni, Mohammad; Hayes, Anna M R; Hamaker, Bruce R

2017-09-01

Gastric emptying rate influences how fast the nutrients of a meal are delivered to the body, and when slow, it moderates glycemic response and may impact satiety. Carbohydrates are one of the macronutrients that trigger the ileal brake, and we hypothesized that slowly digestible carbohydrate (SDC) administered in a premeal load would delay gastric emptying. A crossover design study was conducted with 10 healthy adults using fabricated SDC-microspheres (cooked) that were given 20 minutes before a non-nutritive viscous paste meal. There were 4 treatment arms, each separated by a 1-week washout period, consisting of (1) the paste alone, (2) a rapidly digesting maltodextrin (Polycose) preload followed by the paste 20 minutes later, (3) an SDC-microsphere preload followed by the paste, and (4) a comparably slower SDC-microsphere preload followed by the paste. A 13 C-labeled octanoic acid breath test method was used to measure gastric emptying, with the label incorporated into the non-nutritive paste. The microspheres were less than 1 mm in diameter (a size that does not require breakdown in the stomach before emptying) and, after cooking, were of the same density value. Compared with the paste alone, both of the SDC-microsphere preloads (slow and comparably slower digesting) decreased gastric emptying rate of the paste, with the latter having the most effect (half-emptying times of 1.7, 2.3, and 2.8 hours, respectively [each different at P<.05]). In conclusion, SDCs decreased gastric emptying rate, and this was suggested to be due to a triggering of the ileal brake. Copyright © 2017 Elsevier Inc. All rights reserved.

Prebiotic Low Sugar Chocolate Dairy Desserts: Physical and Optical Characteristics and Performance of PARAFAC and PCA Preference Map.

PubMed

Morais, E C; Esmerino, E A; Monteiro, R A; Pinheiro, C M; Nunes, C A; Cruz, A G; Bolini, Helena M A

2016-01-01

The addition of prebiotic and sweeteners in chocolate dairy desserts opens up new opportunities to develop dairy desserts that besides having a lower calorie intake still has functional properties. In this study, prebiotic low sugar dairy desserts were evaluated by 120 consumers using a 9-point hedonic scale, in relation to the attributes of appearance, aroma, flavor, texture, and overall liking. Internal preference map using parallel factor analysis (PARAFAC) and principal component analysis (PCA) was performed using the consumer data. In addition, physical (texture profile) and optical (instrumental color) analyses were also performed. Prebiotic dairy desserts containing sucrose and sucralose were equally liked by the consumers. These samples were characterized by firmness and gumminess, which can be considered drivers of liking by the consumers. Optimization of the prebiotic low sugar dessert formulation should take in account the choice of ingredients that contribute in a positive manner for these parameters. PARAFAC allowed the extraction of more relevant information in relation to PCA, demonstrating that consumer acceptance analysis can be evaluated by simultaneously considering several attributes. Multiple factor analysis reported Rv value of 0.964, suggesting excellent concordance for both methods. © 2015 Institute of Food Technologists®

Factorial effects of salinity, dietary carbohydrate and moult cycle on digestive carbohydrases and hexokinases in Litopenaeus vannamei (Boone, 1931).

PubMed

Gaxiola, Gabriela; Cuzon, Gerard; García, Tomás; Taboada, Gabriel; Brito, Roberto; Chimal, María Eugenia; Paredes, Adriana; Soto, Luis; Rosas, Carlos; van Wormhoudt, Alain

2005-01-01

Litopenaeus vannamei were reared in close cycle over seven generations and tested for their capacity to digest starch and to metabolise glucose at different stages of the moulting cycle. After acclimation with 42.3% of carbohydrates (HCBH) or 2.3% carbohydrates (LCBH) diets and at high salinity (40 g kg(-1)) or low salinity (15 g kg(-1)), shrimp were sampled and hepatopancreas (HP) were stored. Total soluble protein in HP was affected by the interaction between salinity and moult stages (p<0.05). Specific activity of alpha-amylase ranged from 44 to 241 U mg protein(-1) and a significant interaction between salinity and moult stages was observed (p<0.05), resulting in highest values at stage C for low salinity (mean value 196.4 U mg protein(-1)), and at D0 in high salinity (mean value 175.7 U mg protein(-1)). Specific activity of alpha-glucosidase ranged between 0.09 and 0.63 U mg protein(-1), an interaction between dietary CBH and salinity was observed for the alpha-glucosidase (p<0.05) and highest mean value was found in low salinity-LCBH diet treatment (0.329 U mg protein(-1)). Hexokinase specific activity (range 9-113 mU mg protein(-1)) showed no significant differences when measured at 5 mM glucose (p>0.05). Total hexokinase specific activity (range 17-215 mU mg protein(-1)) showed a significant interaction between dietary CBH and salinity (p<0.05) with highest value (mean value 78.5 mU mg protein(-1)) found in HCBH-high salinity treatment, whereas in the other treatments the activity was not significantly different (mean value 35.93 mU mg protein(-1)). A synergistic effect of dietary CBH, salinity and moult stages over hexokinase IV-like specific activity was also observed (p<0.05). As result of this interaction, the highest value (135.5+/-81 mU mg protein(-1)) was observed in HCBH, high salinity at D0 moult stage. Digestive enzymes activity is enhanced in the presence of high starch diet (HCBH) and hexokinase can be induced at certain moulting stages under

Weight and Metabolic Outcomes After 2 Years on a Low-Carbohydrate Versus Low-Fat Diet

PubMed Central

Foster, Gary D.; Wyatt, Holly R.; Hill, James O.; Makris, Angela P.; Rosenbaum, Diane L.; Brill, Carrie; Stein, Richard I.; Mohammed, B. Selma; Miller, Bernard; Rader, Daniel J.; Zemel, Babette; Wadden, Thomas A.; Tenhave, Thomas; Newcomb, Craig W.; Klein, Samuel

2010-01-01

Background Previous studies comparing low-carbohydrate and low-fat diets have not included a comprehensive behavioral treatment, resulting in suboptimal weight loss. Objective To evaluate the effects of 2-year treatment with a low-carbohydrate or low-fat diet, each of which was combined with a comprehensive lifestyle modification program. Design Randomized parallel-group trial. (ClinicalTrials.gov registration number: NCT00143936) Setting 3 academic medical centers. Patients 307 participants with a mean age of 45.5 years (SD, 9.7 years) and mean body mass index of 36.1 kg/m2 (SD, 3.5 kg/m2). Intervention A low-carbohydrate diet, which consisted of limited carbohydrate intake (20 g/d for 3 months) in the form of low–glycemic index vegetables with unrestricted consumption of fat and protein. After 3 months, participants in the low-carbohydrate diet group increased their carbohydrate intake (5 g/d per wk) until a stable and desired weight was achieved. A low-fat diet consisted of limited energy intake (1200 to 1800 kcal/d; ≤30% calories from fat). Both diets were combined with comprehensive behavioral treatment. Measurements Weight at 2 years was the primary outcome. Secondary measures included weight at 3, 6, and 12 months and serum lipid concentrations, blood pressure, urinary ketones, symptoms, bone mineral density, and body composition throughout the study. Results Weight loss was approximately 11 kg (11%) at 1 year and 7 kg (7%) at 2 years. There were no differences in weight, body composition, or bone mineral density between the groups at any time point. During the first 6 months, the low-carbohydrate diet group had greater reductions in diastolic blood pressure, triglyceride levels, and very-low-density lipoprotein cholesterol levels, lesser reductions in low-density lipoprotein cholesterol levels, and more adverse symptoms than did the low-fat diet group. The low-carbohydrate diet group had greater increases in high-density lipoprotein cholesterol levels

Aerobic sludge digestion under low dissolved oxygen concentrations.

PubMed

Arunachalam, RaviSankar; Shah, Hemant K; Ju, Lu-Kwang

2004-01-01

Low dissolved oxygen (DO) concentrations occur commonly in aerobic digesters treating thickened sludge, with benefits of smaller digester size, much reduced aeration cost, and higher digestion temperature (especially important for plants in colder areas). The effects of low DO concentrations on digestion kinetics were studied using the sludge from municipal wastewater treatment plants in Akron, Ohio, and Los Lunas, New Mexico. The experiments were conducted in both batch digestion and a mixed mode of continuous, fed-batch, and batch operations. The low DO condition was clearly advantageous in eliminating the need for pH control because of the simultaneous occurrence of nitrification and denitrification. However, when compared with fully aerobic (high DO) systems under constant pH control (rare in full-scale plants), low DO concentrations and a higher solids loading had a negative effect on the specific volatile solids (VS) digestion kinetics. Nonetheless, the overall (volumetric) digestion performance depends not only on the specific digestion kinetics, but also the solids concentration, pH, and digester temperature. All of the latter factors favor the low DO digestion of thickened sludge. The significant effect of temperature on low DO digestion was confirmed in the mixed-mode study with the Akron sludge. When compared with the well-known empirical correlation between VS reduction and the product (temperature x solids retention time), the experimental data followed the same trend, but were lower than the correlation predictions. The latter was attributed to the lower digestible VS in the Akron sludge, the slower digestion at low DO concentrations, or both. Through model simulation, the first-order decay constant (kd) was estimated as 0.004 h(-1) in the mixed-mode operations, much lower than those (0.011 to 0.029 h(-1)) obtained in batch digestion. The findings suggested that the interactions among sludges with different treatment ages may have a substantially

A low-carbohydrate as compared with a low-fat diet in severe obesity.

PubMed

Samaha, Frederick F; Iqbal, Nayyar; Seshadri, Prakash; Chicano, Kathryn L; Daily, Denise A; McGrory, Joyce; Williams, Terrence; Williams, Monica; Gracely, Edward J; Stern, Linda

2003-05-22

The effects of a carbohydrate-restricted diet on weight loss and risk factors for atherosclerosis have been incompletely assessed. We randomly assigned 132 severely obese subjects (including 77 blacks and 23 women) with a mean body-mass index of 43 and a high prevalence of diabetes (39 percent) or the metabolic syndrome (43 percent) to a carbohydrate-restricted (low-carbohydrate) diet or a calorie- and fat-restricted (low-fat) diet. Seventy-nine subjects completed the six-month study. An analysis including all subjects, with the last observation carried forward for those who dropped out, showed that subjects on the low-carbohydrate diet lost more weight than those on the low-fat diet (mean [+/-SD], -5.8+/-8.6 kg vs. -1.9+/-4.2 kg; P=0.002) and had greater decreases in triglyceride levels (mean, -20+/-43 percent vs. -4+/-31 percent; P=0.001), irrespective of the use or nonuse of hypoglycemic or lipid-lowering medications. Insulin sensitivity, measured only in subjects without diabetes, also improved more among subjects on the low-carbohydrate diet (6+/-9 percent vs. -3+/-8 percent, P=0.01). The amount of weight lost (P<0.001) and assignment to the low-carbohydrate diet (P=0.01) were independent predictors of improvement in triglyceride levels and insulin sensitivity. Severely obese subjects with a high prevalence of diabetes or the metabolic syndrome lost more weight during six months on a carbohydrate-restricted diet than on a calorie- and fat-restricted diet, with a relative improvement in insulin sensitivity and triglyceride levels, even after adjustment for the amount of weight lost. This finding should be interpreted with caution, given the small magnitude of overall and between-group differences in weight loss in these markedly obese subjects and the short duration of the study. Future studies evaluating long-term cardiovascular outcomes are needed before a carbohydrate-restricted diet can be endorsed. Copyright 2003 Massachusetts Medical Society

Fad diets and obesity--Part IV: Low-carbohydrate vs. low-fat diets.

PubMed

Moyad, Mark A

2005-02-01

The first three parts of this series of articles covered the basics of some of the more popular low-carbohydrate diets, and the theories behind them. In the fourth and final part of this series, some of the more popular low-fat and low-calorie diets, such as the Ornish diet and Weight Watchers, are covered briefly. Recently, several clinical trials of longer duration that compared low-carbohydrate versus low-fat diets have been published. These studies demonstrate that some of the low-carbohydrate diets result in reduced weight in the short-term, but their ability to reduce weight long-term any better than low-fat or other diets has been questioned. Most popular or fad diets have some positive messages contained within them and some preliminary positive short-term results, but overall the compliance rates with any fad diet are very poor over the long-term. The decision to go on any diet should be made with a health professional who can monitor the patient closely.

Low-carbohydrate diet induces metabolic depression: a possible mechanism to conserve glycogen.

PubMed

Winwood-Smith, Hugh S; Franklin, Craig E; White, Craig R

2017-10-01

Long-term studies have found that low-carbohydrate diets are more effective for weight loss than calorie-restricted diets in the short term but equally or only marginally more effective in the long term. Low-carbohydrate diets have been linked to reduced glycogen stores and increased feelings of fatigue. We propose that reduced physical activity in response to lowered glycogen explains the diminishing weight loss advantage of low-carbohydrate compared with low-calorie diets over longer time periods. We explored this possibility by feeding adult Drosophila melanogaster a standard or a low-carbohydrate diet for 9 days and measured changes in metabolic rate, glycogen stores, activity, and body mass. We hypothesized that a low-carbohydrate diet would cause a reduction in glycogen stores, which recover over time, a reduction in physical activity, and an increase in resting metabolic rate. The low-carbohydrate diet reduced glycogen stores, which recovered over time. Activity was unaffected by diet, but metabolic rate was reduced, in the low-carbohydrate group. We conclude that metabolic depression could explain the decreased effectiveness of low-carbohydrate diets over time and recommend further investigation of long-term metabolic effects of dietary interventions and a greater focus on physiological plasticity within the study of human nutrition. Copyright © 2017 the American Physiological Society.

Testing low cost anaerobic digestion (AD) systems

USDA-ARS?s Scientific Manuscript database

To evaluate the potential for low technology and low cost digesters for small dairies, BARC and researchers from the University of Maryland installed six modified Taiwanese-model field-scale (FS) digesters near the original dairy manure digester. The FS units receive the same post-separated liquid ...

Separate influence of dietary carbohydrate and fibre on the metabolic control in diabetes.

PubMed

Riccardi, G; Rivellese, A; Pacioni, D; Genovese, S; Mastranzo, P; Mancini, M

1984-02-01

To clarify the separate influences of digestible carbohydrate and of dietary fibre on blood glucose control and serum lipoproteins, 14 diabetic patients (six Type 1 and eight Type 2) were submitted to three weight-maintaining diets for 10 days each: (1) low carbohydrate/low fibre diet with 42% carbohydrate and 20 g fibre; (2) high carbohydrate/low fibre diet (carbohydrate 53%, fibre 16 g); (3) high carbohydrate/ high fibre diet (carbohydrate 53%, fibre 54 g). In comparison with the low carbohydrate/low fibre diet, the 2-h post-prandial blood glucose and the daily blood glucose profile decreased significantly on the high carbohydrate/high fibre diet, without significant changes during the high carbohydrate/low fibre diet. The diet-induced modifications of blood glucose control were similar in both types of diabetic patients (two-way analysis of variance: F = 5.86, p less than 0.02 for dietary treatment and F = 2.09, NS for type of diabetes). Total and low-density lipoprotein cholesterol were also decreased after the high carbohydrate/high fibre diet in comparison with the low carbohydrate/low fibre diet (p less than 0.001 for both), while they were not significantly modified after the high carbohydrate/low fibre diet. Again the modifications of low density lipoprotein cholesterol induced by diet were similar in both types of diabetic patients (F = 10.02, p less than 0.005 for dietary treatment and F = 0.14 for type of diabetes, NS). High-density lipoprotein cholesterol was lower after the two test diets than after the low carbohydrate/low fibre diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Varying type of forage, concentration of metabolizable protein, and source of carbohydrate affects nutrient digestibility and production by dairy cows.

PubMed

Weiss, W P; St-Pierre, N R; Willett, L B

2009-11-01

The effects of forage source, concentration of metabolizable protein (MP), type of carbohydrate, and their interactions on nutrient digestibility and production were evaluated using a central composite treatment design. All diets (dry basis) contained 50% forage that ranged from 25:75 to 75:25 alfalfa silage:corn silage. Rumen-degradable protein comprised 10.7% of the dry matter (DM) in all diets, but undegradable protein ranged from 4.1 to 7.1%, resulting in dietary MP concentrations of 8.8 to 12.0% of the DM. Dietary starch ranged from 22 to 30% of the DM with a concomitant decrease in neutral detergent fiber concentrations. A total of 15 diets were fed to 36 Holstein cows grouped in 6 blocks. Each block consisted of three 21-d periods, and each cow was assigned a unique sequence of 3 diets, resulting in 108 observations. Milk production and composition, feed intake, and digestibility of major nutrients (via total collection of feces and urine) were measured. Few significant interactions between main effects were observed. Starch concentration had only minor effects on digestibility and production. Replacing corn silage with alfalfa decreased digestibility of N but increased digestibility of neutral detergent fiber. Increasing the concentration of MP increased N digestibility. The concentration (Mcal/kg) of dietary digestible energy (DE) increased linearly as starch concentration increased (very small effect) and was affected by a forage by MP interaction. At low MP, high alfalfa reduced DE concentration, but at high MP, increasing alfalfa increased DE concentration. Increasing alfalfa increased DM and DE intakes, which increased yields of energy-corrected milk, protein, and fat. Increasing MP increased yields of energy-corrected milk and protein. The response in milk protein to changes in MP was much less than predicted using the National Research Council (2001) model.

Top-down systems biology integration of conditional prebiotic modulated transgenomic interactions in a humanized microbiome mouse model

PubMed Central

Martin, Francois-Pierre J; Wang, Yulan; Sprenger, Norbert; Yap, Ivan K S; Rezzi, Serge; Ramadan, Ziad; Peré-Trepat, Emma; Rochat, Florence; Cherbut, Christine; van Bladeren, Peter; Fay, Laurent B; Kochhar, Sunil; Lindon, John C; Holmes, Elaine; Nicholson, Jeremy K

2008-01-01

Gut microbiome–host metabolic interactions affect human health and can be modified by probiotic and prebiotic supplementation. Here, we have assessed the effects of consumption of a combination of probiotics (Lactobacillus paracasei or L. rhamnosus) and two galactosyl-oligosaccharide prebiotics on the symbiotic microbiome–mammalian supersystem using integrative metabolic profiling and modeling of multiple compartments in germ-free mice inoculated with a model of human baby microbiota. We have shown specific impacts of two prebiotics on the microbial populations of HBM mice when co-administered with two probiotics. We observed an increase in the populations of Bifidobacterium longum and B. breve, and a reduction in Clostridium perfringens, which were more marked when combining prebiotics with L. rhamnosus. In turn, these microbial effects were associated with modulation of a range of host metabolic pathways observed via changes in lipid profiles, gluconeogenesis, and amino-acid and methylamine metabolism associated to fermentation of carbohydrates by different bacterial strains. These results provide evidence for the potential use of prebiotics for beneficially modifying the gut microbial balance as well as host energy and lipid homeostasis. PMID:18628745

Prebiotic potential of L-sorbose and xylitol in promoting the growth and metabolic activity of specific butyrate-producing bacteria in human fecal culture.

PubMed

Sato, Tadashi; Kusuhara, Shiro; Yokoi, Wakae; Ito, Masahiko; Miyazaki, Kouji

2017-01-01

Dietary low-digestible carbohydrates (LDCs) affect gut microbial metabolism, including the production of short-chain fatty acids. The ability of various LDCs to promote butyrate production was evaluated in in vitro human fecal cultures. Fecal suspensions from five healthy males were anaerobically incubated with various LDCs. L-Sorbose and xylitol markedly promoted butyrate formation in cultures. Bacterial 16S rRNA gene-based denaturing gradient gel electrophoresis analyses of these fecal cultures revealed a marked increase in the abundance of bacteria closely related to the species Anaerostipes hadrus or A. caccae or both, during enhanced butyrate formation from L-sorbose or xylitol. By using an agar plate culture, two strains of A. hadrus that produced butyrate from each substrate were isolated from the feces of two donors. Furthermore, of 12 species of representative colonic butyrate producers, only A. hadrus and A. caccae demonstrated augmented butyrate production from L-sorbose or xylitol. These findings suggest that L-sorbose and xylitol cause prebiotic stimulation of the growth and metabolic activity of Anaerostipes spp. in the human colon. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The prebiotic inulin as a functional food - a review.

PubMed

Fan, C-H; Cao, J-H; Zhang, F-C

2016-07-01

The newborn digestive tract is rapidly colonized right after birth. The type of feeding could significantly influence this colonization process. Infant formulas like inulin try to mimic the bifidogenic effects of human milk by addition of prebiotics. Moreover, studies in the recent past have evidenced important effects of inulin during early infant life. The present review article will highlight recent updates about the use of inulin in the pediatric clinical setting.

Interference of age and supplementation of direct-fed microbial and essential oil in the activity of digestive enzymes and expression of genes related to transport and digestion of carbohydrates and proteins in the small intestine of broilers.

PubMed

Fernandez-Alarcon, M F; Trottier, N; Steibel, J P; Lunedo, R; Campos, D M B; Santana, A M; Pizauro, J M; Furlan, R L; Furlan, L R

2017-08-01

The objectives of this study were to describe alterations that age and dietary inclusion of direct-fed microbial (DFM) Bacillus subtilis (BS) and a specific essential oil (EO) blend (carvacrol, cinnamaldehyde, cineol, and pepper extract) causes in the activity of digestive enzymes (maltase: MALT; aminopeptidase-N: APN; intestinal alkaline phosphate: IAP) and expression patterns of genes related to transport (oligopeptide transporter gene: SLC15A1; Na+-dependent glucose and galactose transporter gene: SLC5A1; Na+-independent glucose, galactose, and fructose transporter gene: SLC2A2; ATPase, Na+/K+ transporting gene: ATP1A1) and digestion (aminopeptidase-N gene: ANPEP; maltase-glucoamylase gene: MGAM; Sucrase-isomaltase gene: SI) of carbohydrates and proteins in the small intestine of broilers. Also, the objective was to analyze if growth performance of broilers is affected by supplementation (BS and EO blend). Day-old male broiler chicks (n = 1,320) were assigned to 5 treatments. Diets included a basal diet (BD) as a negative control (CON); experimental diets were BD + BS; BD + BS + EO; BD + EO; BD + antibiotic growth promoter (AGP) avilamycin was the positive control. Performance was evaluated between 1 to 42 d. Transcript abundance of transport-related genes and digestion-related genes were assayed by RT-qPCR and determined at d 7, 21, and 42. MALT-, APN-, and IAP-specific activities were determined at d 7, 21, and 42. Broilers fed BS had greater SLC15A1 mRNA abundance compared to CON, while EO and AGP were related to higher activities of IAP and APN. Analysis over time revealed higher abundance of MGAM, SLC2A2, SLC15A1, SLC5A1 and SI mRNA at d 42 when compared to d 7. Activity of IAP decreased after d 7 and activity of MALT increased with age. The current study suggests that age had effect over carbohydrate and protein transport and carbohydrate digestion. The supplementation of BS DFM hade evident effect over protein transport and that the use of EO in the diet

Carbohydrate terminology and classification.

PubMed

Cummings, J H; Stephen, A M

2007-12-01

Dietary carbohydrates are a group of chemically defined substances with a range of physical and physiological properties and health benefits. As with other macronutrients, the primary classification of dietary carbohydrate is based on chemistry, that is character of individual monomers, degree of polymerization (DP) and type of linkage (alpha or beta), as agreed at the Food and Agriculture Organization/World Health Organization Expert Consultation in 1997. This divides carbohydrates into three main groups, sugars (DP 1-2), oligosaccharides (short-chain carbohydrates) (DP 3-9) and polysaccharides (DP> or =10). Within this classification, a number of terms are used such as mono- and disaccharides, polyols, oligosaccharides, starch, modified starch, non-starch polysaccharides, total carbohydrate, sugars, etc. While effects of carbohydrates are ultimately related to their primary chemistry, they are modified by their physical properties. These include water solubility, hydration, gel formation, crystalline state, association with other molecules such as protein, lipid and divalent cations and aggregation into complex structures in cell walls and other specialized plant tissues. A classification based on chemistry is essential for a system of measurement, predication of properties and estimation of intakes, but does not allow a simple translation into nutritional effects since each class of carbohydrate has overlapping physiological properties and effects on health. This dichotomy has led to the use of a number of terms to describe carbohydrate in foods, for example intrinsic and extrinsic sugars, prebiotic, resistant starch, dietary fibre, available and unavailable carbohydrate, complex carbohydrate, glycaemic and whole grain. This paper reviews these terms and suggests that some are more useful than others. A clearer understanding of what is meant by any particular word used to describe carbohydrate is essential to progress in translating the growing knowledge of the

Probiotics and prebiotics--perspectives and challenges.

PubMed

Figueroa-González, Ivonne; Quijano, Guillermo; Ramírez, Gerardo; Cruz-Guerrero, Alma

2011-06-01

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed. Copyright © 2011 Society of Chemical Industry.

Carbohydrate Analysis

NASA Astrophysics Data System (ADS)

Bemiller, James N.

Carbohydrates are important in foods as a major source of energy, to impart crucial textural properties, and as dietary fiber which influences physiological processes. Digestible carbohydrates, which are converted into monosaccharides, which are absorbed, provide metabolic energy. Worldwide, carbohydrates account for more than 70% of the caloric value of the human diet. It is recommended that all persons should limit calories from fat (the other significant source) to not more than 30% and that most of the carbohydrate calories should come from starch. Nondigestible polysaccharides (all those other than starch) comprise the major portion of dietary fiber (Sect. 10.5). Carbohydrates also contribute other attributes, including bulk, body, viscosity, stability to emulsions and foams, water-holding capacity, freeze-thaw stability, browning, flavors, aromas, and a range of desirable textures (from crispness to smooth, soft gels). They also provide satiety. Basic carbohydrate structures, chemistry, and terminology can be found in references (1, 2).

Carbohydrate composition and in vitro digestibility of dry matter and nonstarch polysaccharides in corn, sorghum, and wheat and coproducts from these grains.

PubMed

Jaworski, N W; Lærke, H N; Bach Knudsen, K E; Stein, H H

2015-03-01

The objectives of this work were to determine carbohydrate composition and in vitro digestibility of DM and nonstarch polysaccharides (NSP) in corn, wheat, and sorghum and coproducts from these grains. In the initial part of this work, the carbohydrate composition of 12 feed ingredients was determined. The 12 ingredients included 3 grains (corn, sorghum, and wheat), 3 coproducts from the dry grind industry (corn distillers dried grains with solubles [DDGS] and 2 sources of sorghum DDGS), 4 coproducts from the wet milling industry (corn gluten meal, corn gluten feed, corn germ meal, and corn bran), and 2 coproducts from the flour milling industry (wheat middlings and wheat bran). Results indicated that grains contained more starch and less NSP compared with grain coproducts. The concentration of soluble NSP was low in all ingredients. Cellulose, arabinoxylans, and other hemicelluloses made up approximately 22, 49, and 29% (DM basis), respectively, of the NSP in corn and corn coproducts and approximately 25, 43, and 32% (DM basis), respectively, of the NSP in sorghum and sorghum DDGS. Cellulose, arabinoxylans, and other hemicelluloses made up approximately 16, 64, and 20% (DM basis), respectively, of the NSP in wheat and wheat coproducts. The concentration of lignin in grains was between 0.8 and 1.8% (DM basis), whereas coproducts contained between 2.2 and 11.5% lignin (DM basis). The in vitro ileal digestibility of NSP was close to zero or negative for all feed ingredients, indicating that pepsin and pancreas enzymes have no effect on in vitro degradation of NSP. A strong negative correlation ( = 0.97) between in vitro ileal digestibility of DM and the concentration of NSP in feed ingredients was observed. In vitro total tract digestibility of NSP ranged from 6.5% in corn bran to 57.3% in corn gluten meal. In conclusion, grains and grain coproducts contain mostly insoluble NSP and arabinoxylans make up the majority of the total NSP fraction. The in vitro

Regulation of low-density lipoprotein subfractions by carbohydrates.

PubMed

Gerber, Philipp A; Berneis, Kaspar

2012-07-01

This article aims at reviewing the recent findings that have been made concerning the crosstalk of carbohydrate metabolism with the generation of small, dense low-density lipoprotein (LDL) particles, which are known to be associated with an adverse cardiovascular risk profile. Studies conducted during the past few years have quite unanimously shown that the quantity of carbohydrates ingested is associated with a decrease of LDL particle size and an increase in its density. Conversely, diets that aim at a reduction of carbohydrate intake are able to improve LDL quality. Furthermore, a reduction of the glycaemic index without changing the amount of carbohydrates ingested has similar effects. Diseases with altered carbohydrate metabolism, for example, type 2 diabetes, are associated with small, dense LDL particles. Finally, even the kind of monosaccharide the carbohydrate intake consists of is important concerning LDL particle size: fructose has been shown to alter the LDL particle subclass profile more adversely than glucose in many recent studies. LDL particle quality, rather than its quantity, is affected by carbohydrate metabolism, which is of clinical importance, in particular, in the light of increased carbohydrate consumption in today's world.

Beneficial effect of low carbohydrate in low calorie diets on visceral fat reduction in type 2 diabetic patients with obesity.

PubMed

Miyashita, Yoh; Koide, Nobukiyo; Ohtsuka, Masaki; Ozaki, Hiroshi; Itoh, Yoshiaki; Oyama, Tomokazu; Uetake, Takako; Ariga, Kiyoko; Shirai, Kohji

2004-09-01

The adequate composition of carbohydrate and fat in low calorie diets for type 2 diabetes mellitus patients with obesity is not fully established. The aim of this study was to investigate the effects of low carbohydrate diet on glucose and lipid metabolism, especially on visceral fat accumulation, and comparing that of a high carbohydrate diet. Obese subjects with type 2 diabetes mellitus were randomly assigned to take a low calorie and low carbohydrate diet (n = 11, 1000 kcal per day, protein:carbohydrate:fat = 25:40:35) or a low calorie and high carbohydrate diet (n = 11, 1000 kcal per day, protein:carbohydrate:fat = 25:65:10) for 4 weeks. Similar decreases in body weight and serum glucose levels were observed in both groups. Fasting serum insulin levels were reduced in the low carbohydrate diet group compared to the high carbohydrate diet group (-30% versus -10%, P < 0.05). Total serum cholesterol and triglyceride levels decreased in both groups, but were not significantly different from each other. High-density lipoprotein-cholesterol (HDL-C) increased in the low carbohydrate diet group but not in the high carbohydrate diet group (+15% versus 0%, P < 0.01). There was a larger decrease in visceral fat area measured by computed tomography in the low carbohydrate diet group compared to the high carbohydrate diet group (-40 cm(2) versus -10 cm(2), P < 0.05). The ratio of visceral fat area to subcutaneous fat area did not change in the high carbohydrate diet group (from 0.70 to 0.68), but it decreased significantly in the low carbohydrate diet group (from 0.69 to 0.47, P < 0.005). These results suggest that, when restrict diet was made isocaloric, a low calorie/low carbohydrate diet might be more effective treatment for a reduction of visceral fat, improved insulin sensitivity and increased in HDL-C levels than low calorie/high carbohydrate diet in obese subjects with type 2 diabetes mellitus.

Gut feedback mechanisms and food intake: a physiological approach to slow carbohydrate bioavailability.

PubMed

Zhang, Genyi; Hasek, Like Y; Lee, Byung-Hoo; Hamaker, Bruce R

2015-04-01

Glycemic carbohydrates in foods are an important macronutrient providing the biological fuel of glucose for a variety of physiological processes. A classification of glycemic carbohydrates into rapidly digestible carbohydrate (RDC) and slowly digestible carbohydrate (SDC) has been used to specify their nutritional quality related to glucose homeostasis that is essential to normal functioning of the brain and critical to life. Although there have been many studies and reviews on slowly digestible starch (SDS) and SDC, the mechanisms of their slow digestion and absorption were mostly investigated from the material side without considering the physiological processes of their in vivo digestion, absorption, and most importantly interactions with other food components and the gastrointestinal tract. In this article, the physiological processes modulating the bioavailability of carbohydrates, specifically the rate and extent of their digestion and absorption as well as the related locations, in a whole food context, will be discussed by focusing on the activities of the gastrointestinal tract including glycolytic enzymes and glucose release, sugar sensing, gut hormones, and neurohormonal negative feedback mechanisms. It is hoped that a deep understanding of these physiological processes will facilitate the development of innovative dietary approaches to achieve desired carbohydrate or glucose bioavailability for improved health.

Endothelial Function and Weight Loss: Comparison of Low-Carbohydrate and Low-Fat Diets

PubMed Central

Mohler, Emile R.; Sibley, Alexandra A.; Stein, Richard; Davila-Roman, Victor; Wyatt, Holly; Badellino, Karen; Rader, Daniel J.; Klein, Samuel; Foster, Gary D.

2012-01-01

The effect of weight loss on obesity-associated endothelial dysfunction is not clear because of conflicting data, demonstrating both improvement and no change in endothelial function after weight loss in obese subjects. A two-year prospective study (n=121) was conducted to examine: 1) the effect of obesity and weight loss (either a low-carbohydrate or and low-fat diet) on flow mediated vasodilatation (FMD), a measure of endothelial function. Participants reduced body weight by 7.1±4.4%, 8.7±6.8% 7.1±7.8% and 4.1±7.7% at 3, 6, 12 and 24 months, respectively with no significant differences between the low-fat and low-carbohydrate groups. Endothelial function was inversely correlated with waist circumference, triglyceride level, and directly correlated with leptin in obese persons prior to weight loss. These weight losses did not confer any improvements in FMD. There were no differences between the low-fat and low-carbohydrate diets in FMD at any time point. At 6 months (r = 0.26, p = 0.04) and one year (r = 0.28, p = 0.03), there were positive correlations between change in FMD and change in leptin but not at two years. There was no significant improvement in endothelial function after 7.1±7.8% weight loss at one year and 4.1±7.7% at two years, achieved by either a low carbohydrate or a low fat diet. PMID:23404949

A comparison of low-carbohydrate vs. high-carbohydrate diets: energy restriction, nutrient quality and correlation to body mass index.

PubMed

Bowman, Shanthy A; Spence, Joseph T

2002-06-01

To evaluate free-living adults' diets that ranged from very low to high amounts of carbohydrate for their energy content, nutritional quality and correlation to Body Mass Index. Adults ages 19 years and older, who had complete dietary intake data on day-1 of the USDA's 1994 to 1996 Continuing Survey of Food Intakes by Individuals (CSFII 1994-1996), were divided into four groups--very low, low, moderate and high carbohydrate--based on the percent total energy from carbohydrate. Mean energy, nutrient, food intakes and Body Mass Index values were compared among the groups. SUDAAN software package was used for the data analysis and pair-wise mean comparisons (p < 0.05). The high-carbohydrate diet was lower in energy and energy density (number of kilocalories per gram of total amount of food consumed) than the other three diets. Macronutrient composition varied significantly among all the four groups. Nutrient density (amount of nutrient per 1,000 kilocalories of energy consumed) of vitamin A, carotene, vitamin C, folate, calcium, magnesium and iron increased and that of vitamin B12 and zinc decreased with an increase in the percent total energy from carbohydrate. The high-carbohydrate group ate more of low-fat foods, grain products and fruits. This group also had the lowest sodium intake. Adults eating a high-carbohydrate diet are more likely to have Body Mass Index values below 25. A study of diets of free-living adults in the U.S. showed that diets high in carbohydrate were both energy restrictive and nutritious and may be adopted for successful weight management.

A food additive with prebiotic properties of an α-d-glucan from lactobacillus plantarum DM5.

PubMed

Das, Deeplina; Baruah, Rwivoo; Goyal, Arun

2014-08-01

An α-d-glucan produced by Lactobacillus plantarum DM5 was explored for in vitro prebiotic activities. Glucan-DM5 demonstrated 21.6% solubility, 316.9% water holding capacity, 86.2% flocculation activity, 71.4% emulsification activity and a degradation temperature (Td) of 292.2°C. Glucan-DM5 exhibited lowest digestibility of 0.54% by artificial gastric juice, 0.21% by intestinal fluid and 0.32% by α-amylase whereas the standard prebiotic inulin, showed 25.23%, 5.97% and 19.13%, hydrolysis, respectively. Prebiotic activity assay of glucan-DM5 displayed increased growth of probiotic bacteria such as Bifidobacterium infantis and Lactobacillus acidophilus, but did not support the growth of non-probiotic bacteria such as Escherichia coli and Enterobacter aerogenes. The overall findings indicated that glucan from L. plantarum DM5 can serve as a potential prebiotic additive for food products. Copyright © 2014 Elsevier B.V. All rights reserved.

A low-carbohydrate, ketogenic diet versus a low-fat diet to treat obesity and hyperlipidemia: a randomized, controlled trial.

PubMed

Yancy, William S; Olsen, Maren K; Guyton, John R; Bakst, Ronna P; Westman, Eric C

2004-05-18

Low-carbohydrate diets remain popular despite a paucity of scientific evidence on their effectiveness. To compare the effects of a low-carbohydrate, ketogenic diet program with those of a low-fat, low-cholesterol, reduced-calorie diet. Randomized, controlled trial. Outpatient research clinic. 120 overweight, hyperlipidemic volunteers from the community. Low-carbohydrate diet (initially, <20 g of carbohydrate daily) plus nutritional supplementation, exercise recommendation, and group meetings, or low-fat diet (<30% energy from fat, <300 mg of cholesterol daily, and deficit of 500 to 1000 kcal/d) plus exercise recommendation and group meetings. Body weight, body composition, fasting serum lipid levels, and tolerability. A greater proportion of the low-carbohydrate diet group than the low-fat diet group completed the study (76% vs. 57%; P = 0.02). At 24 weeks, weight loss was greater in the low-carbohydrate diet group than in the low-fat diet group (mean change, -12.9% vs. -6.7%; P < 0.001). Patients in both groups lost substantially more fat mass (change, -9.4 kg with the low-carbohydrate diet vs. -4.8 kg with the low-fat diet) than fat-free mass (change, -3.3 kg vs. -2.4 kg, respectively). Compared with recipients of the low-fat diet, recipients of the low-carbohydrate diet had greater decreases in serum triglyceride levels (change, -0.84 mmol/L vs. -0.31 mmol/L [-74.2 mg/dL vs. -27.9 mg/dL]; P = 0.004) and greater increases in high-density lipoprotein cholesterol levels (0.14 mmol/L vs. -0.04 mmol/L [5.5 mg/dL vs. -1.6 mg/dL]; P < 0.001). Changes in low-density lipoprotein cholesterol level did not differ statistically (0.04 mmol/L [1.6 mg/dL] with the low-carbohydrate diet and -0.19 mmol/L [-7.4 mg/dL] with the low-fat diet; P = 0.2). Minor adverse effects were more frequent in the low-carbohydrate diet group. We could not definitively distinguish effects of the low-carbohydrate diet and those of the nutritional supplements provided only to that group. In addition

Early low volume oral synbiotic/prebiotic supplemented enteral stimulation of the gut in patients with severe acute pancreatitis: a prospective feasibility study.

PubMed

Plaudis, H; Pupelis, G; Zeiza, K; Boka, V

2012-01-01

Experience with administration of synbiotics (prebiotics/probiotics) in patients with severe acute pancreatitis (SAP) has demonstrated immunomodulatory capacity. The aim of this trial was evaluation of the feasibility and perspective of early clinical application of oral synbiotic/prebiotic supplements in patients with SAP. 90 SAP patients were enrolled during the period from 2005-2008. Patients were stratified according to the feeding mode. CONTROL (n = 32) group received standard whole protein feeding formula. SYNBIO (n = 30) and FIBRE groups (n = 28) received early (within first 24-48 hours) synbiotic or prebiotic supplements. Oral administration of synbiotics or prebiotics was commenced when patients were able to sip water. Daily provided average volume and calories of synbiotic/prebiotic blends were smaller compared to the CONTROL, p = 0.001. Oral administration of synbiotic/prebiotic supplements was associated with lower infection rate (pancreatic and peripancreatic necrosis) compared to the CONTROL, (p = 0.03; p = 0.001), lower rate of surgical interventions, p = 0.005, shorter ICU (p = 0.05) and hospital stay (p = 0.03). Synbiotic supplemented enteral stimulation of the gut resulted in reduced mortality rate compared to the CONTROL, p = 0.02. Early low volume oral synbiotic/prebiotic supplemented enteral stimulation of the gut seems to be a potentially valuable complement to the routine treatment protocol of SAP.

Systematic review of randomized controlled trials of low-carbohydrate vs. low-fat/low-calorie diets in the management of obesity and its comorbidities.

PubMed

Hession, M; Rolland, C; Kulkarni, U; Wise, A; Broom, J

2009-01-01

There are few studies comparing the effects of low-carbohydrate/high-protein diets with low-fat/high-carbohydrate diets for obesity and cardiovascular disease risk. This systematic review focuses on randomized controlled trials of low-carbohydrate diets compared with low-fat/low-calorie diets. Studies conducted in adult populations with mean or median body mass index of > or =28 kg m(-2) were included. Thirteen electronic databases were searched and randomized controlled trials from January 2000 to March 2007 were evaluated. Trials were included if they lasted at least 6 months and assessed the weight-loss effects of low-carbohydrate diets against low-fat/low-calorie diets. For each study, data were abstracted and checked by two researchers prior to electronic data entry. The computer program Review Manager 4.2.2 was used for the data analysis. Thirteen articles met the inclusion criteria. There were significant differences between the groups for weight, high-density lipoprotein cholesterol, triacylglycerols and systolic blood pressure, favouring the low-carbohydrate diet. There was a higher attrition rate in the low-fat compared with the low-carbohydrate groups suggesting a patient preference for a low-carbohydrate/high-protein approach as opposed to the Public Health preference of a low-fat/high-carbohydrate diet. Evidence from this systematic review demonstrates that low-carbohydrate/high-protein diets are more effective at 6 months and are as effective, if not more, as low-fat diets in reducing weight and cardiovascular disease risk up to 1 year. More evidence and longer-term studies are needed to assess the long-term cardiovascular benefits from the weight loss achieved using these diets.

Prebiotics Modulate the Effects of Antibiotics on Gut Microbial Diversity and Functioning in Vitro.

PubMed

Johnson, Laura P; Walton, Gemma E; Psichas, Arianna; Frost, Gary S; Gibson, Glenn R; Barraclough, Timothy G

2015-06-04

Intestinal bacteria carry out many fundamental roles, such as the fermentation of non-digestible dietary carbohydrates to produce short chain fatty acids (SCFAs), which can affect host energy levels and gut hormone regulation. Understanding how to manage this ecosystem to improve human health is an important but challenging goal. Antibiotics are the front line of defence against pathogens, but in turn they have adverse effects on indigenous microbial diversity and function. Here, we have investigated whether dietary supplementation--another method used to modulate gut composition and function--could be used to ameliorate the side effects of antibiotics. We perturbed gut bacterial communities with gentamicin and ampicillin in anaerobic batch cultures in vitro. Cultures were supplemented with either pectin (a non-fermentable fibre), inulin (a commonly used prebiotic that promotes the growth of beneficial bacteria) or neither. Although antibiotics often negated the beneficial effects of dietary supplementation, in some treatment combinations, notably ampicillin and inulin, dietary supplementation ameliorated the effects of antibiotics. There is therefore potential for using supplements to lessen the adverse effects of antibiotics. Further knowledge of such mechanisms could lead to better therapeutic manipulation of the human gut microbiota.

Impact of feed carbohydrates and nitrogen source on the production of soluble microbial products (SMPs) in anaerobic digestion.

PubMed

Le, Chencheng; Stuckey, David C

2017-10-01

Six stirred fill-and-draw batch reactors with a range of carbohydrate feeds (glucose, fructose and sucrose), and nitrogen sources (NH 4 Cl, urea) at various concentrations were used to investigate the effect of feed composition on the production of soluble microbial products (SMPs) during anaerobic digestion (AD). To gain greater insights into the SMPs produced, the composition of various fractions was analyzed, while the low molecular weight (MW) SMPs generated with different feeds and nutrients were collected and chemically analyzed using GC-MS. Other organic solutes such as free amino acids were determined using HPLC, and this level of chemical analysis has never been carried out in past work because of analytical limitations. It was found that the presence of ammonium salts rather than urea at 200 mg/L stimulated the production of not only volatile fatty acids, but also SMPs of different MW fractions, and reduced the production of biogas significantly. The study also revealed that the type of SMP that dominates in a particular system depends on the chemical characteristics of the feed, and this insight has implications on the composition of the effluent from anaerobic digesters (and their potential chlorination by-products), and membrane fouling in membrane bioreactors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Renal function following long-term weight loss in individuals with abdominal obesity on a very-low-carbohydrate diet vs high-carbohydrate diet.

PubMed

Brinkworth, Grant D; Buckley, Jonathan D; Noakes, Manny; Clifton, Peter M

2010-04-01

A frequently cited concern of very-low-carbohydrate diets is the potential for increased risk of renal disease associated with a higher protein intake. However, to date, no well-controlled randomized studies have evaluated the long-term effects of very-low-carbohydrate diets on renal function. To study this issue, renal function was assessed in 68 men and women with abdominal obesity (age 51.5+/-7.7 years, body mass index [calculated as kg/m(2)] 33.6+/-4.0) without preexisting renal dysfunction who were randomized to consume either an energy-restricted ( approximately 1,433 to 1,672 kcal/day), planned isocaloric very-low-carbohydrate (4% total energy as carbohydrate [14 g], 35% protein [124 g], 61% fat [99 g]), or high-carbohydrate diet (46% total energy as carbohydrate [162 g], 24% protein [85 g], 30% fat [49 g]) for 1 year. Body weight, serum creatinine, estimated glomerular filtration rate and urinary albumin excretion were assessed before and after 1 year (April 2006-July 2007). Repeated measures analysis of variance was conducted. Weight loss was similar in both groups (very-low-carbohydrate: -14.5+/-9.7 kg, high-carbohydrate: -11.6+/-7.3 kg; P=0.16). By 1 year, there were no changes in either group in serum creatinine levels (very-low-carbohydrate: 72.4+/-15.1 to 71.3+/-13.8 mumol/L, high-carbohydrate: 78.0+/-16.0 to 77.2+/-13.2 mumol/L; P=0.93 time x diet effect) or estimated glomerular filtration rate (very-low-carbohydrate: 90.0+/-17.0 to 91.2+/-17.8 mL/min/1.73 m(2), high-carbohydrate: 83.8+/-13.8 to 83.6+/-11.8 mL/min/1.73 m(2); P=0.53 time x diet effect). All but one participant was classified as having normoalbuminuria at baseline, and for these participants, urinary albumin excretion values remained in the normoalbuminuria range at 1 year. One participant in high-carbohydrate had microalbuminuria (41.8 microg/min) at baseline, which decreased to a value of 3.1 microg/min (classified as normoalbuminuria) at 1 year. This study provides preliminary

Low-carbohydrate diets: what are the potential short- and long-term health implications?

PubMed

Bilsborough, Shane A; Crowe, Timothy C

2003-01-01

Low-carbohydrate diets for weight loss are receiving a lot of attention of late. Reasons for this interest include a plethora of low-carbohydrate diet books, the over-sensationalism of these diets in the media and by celebrities, and the promotion of these diets in fitness centres and health clubs. The re-emergence of low-carbohydrate diets into the spotlight has lead many people in the general public to question whether carbohydrates are inherently 'bad' and should be limited in the diet. Although low-carbohydrate diets were popular in the 1970s they have resurged again yet little scientific fact into the true nature of how these diets work or, more importantly, any potential for serious long-term health risks in adopting this dieting practice appear to have reached the mainstream literature. Evidence abounds that low-carbohydrate diets present no significant advantage over more traditional energy-restricted, nutritionally balanced diets both in terms of weight loss and weight maintenance. Studies examining the efficacy of using low-carbohydrate diets for long-term weight loss are few in number, however few positive benefits exist to promote the adoption of carbohydrate restriction as a realistic, and more importantly, safe means of dieting. While short-term carbohydrate restriction over a period of a week can result in a significant loss of weight (albeit mostly from water and glycogen stores), of serious concern is what potential exists for the following of this type of eating plan for longer periods of months to years. Complications such as heart arrhythmias, cardiac contractile function impairment, sudden death, osteoporosis, kidney damage, increased cancer risk, impairment of physical activity and lipid abnormalities can all be linked to long-term restriction of carbohydrates in the diet. The need to further explore and communicate the untoward side-effects of low-carbohydrate diets should be an important public health message from nutrition professionals.

Psychrophilic anaerobic digestion of guinea pig manure in low-cost tubular digesters at high altitude.

PubMed

Garfí, Marianna; Ferrer-Martí, Laia; Villegas, Vidal; Ferrer, Ivet

2011-05-01

Guinea pig is one of the most common livestock in rural communities of the Andes. The aim of this research was to study the anaerobic digestion of guinea pig manure in low-cost unheated tubular digesters at high altitude. To this end, the performance of two pilot digesters was monitored during 7 months; and two greenhouse designs were compared. In the dome roof digester the temperature and biogas production were significantly higher than in the shed roof digester. However, the biogas production rate was low (0.04 m(biogas)(3)m(digester)(-3) d(-1)), which is attributed to the low organic loading rate (0.6 kg(VS)m(digester)(-3)d(-1)) and temperature (23°C) of the system, among other factors. In a preliminary fertilization study, the potato yield per hectare was increased by 100% using the effluent as biofertilizer. Improving manure management techniques, increasing the organic loading rate and co digesting other substrates may be considered to enhance the process. Copyright © 2011 Elsevier Ltd. All rights reserved.

Potential Prebiotic Properties of Almond (Amygdalus communis L.) Seeds▿

PubMed Central

Mandalari, G.; Nueno-Palop, C.; Bisignano, G.; Wickham, M. S. J.; Narbad, A.

2008-01-01

Almonds are known to have a number of nutritional benefits, including cholesterol-lowering effects and protection against diabetes. They are also a good source of minerals and vitamin E, associated with promoting health and reducing the risk for chronic disease. For this study we investigated the potential prebiotic effect of almond seeds in vitro by using mixed fecal bacterial cultures. Two almond products, finely ground almonds (FG) and defatted finely ground almonds (DG), were subjected to a combined model of the gastrointestinal tract which included in vitro gastric and duodenal digestion, and the resulting fractions were subsequently used as substrates for the colonic model to assess their influence on the composition and metabolic activity of gut bacteria populations. FG significantly increased the populations of bifidobacteria and Eubacterium rectale, resulting in a higher prebiotic index (4.43) than was found for the commercial prebiotic fructooligosaccharides (4.08) at 24 h of incubation. No significant differences in the proportions of gut bacteria groups were detected in response to DG. The increase in the numbers of Eubacterium rectale during fermentation of FG correlated with increased butyrate production. In conclusion, we have shown that the addition of FG altered the composition of gut bacteria by stimulating the growth of bifidobacteria and Eubacterium rectale. PMID:18502914

Prebiotic Synthesis of Diaminopyrimidine and Thiocytosine

NASA Technical Reports Server (NTRS)

Robertson, Michael P.; Levy, Matthew; Miller, Stanley L.

1996-01-01

The reaction of guanidine hydrochloride with cyanoacetaldehyde gives high yields (40-85%) of 2,4-diaminopyrimidine under the concentrated conditions of a drying lagoon model of prebiotic synthesis, in contrast to the low yields previously obtained under more dilute conditions. The prebiotic source of cyanoacetaldehyde, cyanoacetylene, is produced from electric discharges under reducing conditions. The effect of pH and concentration of guanidine hydrochloride on the rate of synthesis and yield of diaminopyrimidine were investigated, as well as the hydrolysis of diaminopyrimidine to cytosine, isocytosine, and uracil. Thiourea also reacts with cyanoacetaldehyde to give 2-thiocytosine, but the pyrimidine yields are much lower than with guanidine hydrochloride or urea. Thiocytosine hydrolyzes to thiouracil and cytosine and then to uracil. This synthesis would have been a significant prebiotic source of 2-thiopyrimidines and 5-substituted derivatives of thiouracil, many of which occur in tRNA. The applicability of these results to the drying lagoon model of prebiotic synthesis was tested by dry-down experiments where dilute solutions of cyanoacetaldehyde, guanidine hydrochloride, and 0.5 M NaCl were evaporated over varying periods of time. The yields of diaminopyrimidine varied from 1 to 7%. These results show that drying lagoons and beaches may have been major sites of prebiotic syntheses.

Common Prairie feeds with different soluble and insoluble fractions used for CPM diet formulation in dairy cattle: Impact of carbohydrate-protein matrix structure on protein and other primary nutrient digestion

NASA Astrophysics Data System (ADS)

Peng, Quanhui; Wang, Zhisheng; Zhang, Xuewei; Yu, Peiqiang

2014-03-01

An experiment was conducted to investigate the relationship of carbohydrates molecular spectral characteristics to rumen degradability of primary nutrients in Prairie feeds in dairy cattle. In total, 12 different types of feeds were selected, each type of feed was from three different source with total 37 samples. Six types of them were energy-sourced feeds and the others were protein-sourced feeds. The carbohydrates molecular spectral intensity of various functional groups were collected using Fourier transform infrared attenuated total reflectance (ATR-FT/IR) spectroscopy. In the in situ study, the results showed that the rumen digestibility and digestible fractions of primary nutrients (DM, OM, NCP, and CP) were significantly different (P < 0.05) among the feeds. The spectral bands features were significantly different (P < 0.05) among the feeds. Spectral intensities of A_Cell, H_1415 and H_1370 were weakly positively correlated with in situ rumen digestibility and digestible fractions of DM, OM and NCP. Spectral intensities of H_1150, H_1015, A_1, and A_3 were weakly negatively associated with in situ rumen degradation of CP. Spectral intensities of A_1240 and H_1240, mainly associated with cellulosic compounds, were correlated with rumen CP degradation. The multiple regression analysis demonstrated that the spectral intensities of A_3 and H_1415 played the most important role and could be used as a potential tool to predict rumen protein degradation of feeds in dairy cattle. In conclusion, this study showed that the carbohydrates as a whole have an effect on protein rumen degradation, rather than cellulose alone, indicating carbohydrate-protein matrix structure impact protein utilization in dairy cattle. The non-invasive molecular spectral technique (ATR-FT/IR) could be used as a rapid potential tool to predict rumen protein degradation of feedstuffs by using molecular spectral bands intensities in carbohydrate fingerprint region.

The impact of pollen consumption on honey bee (Apis mellifera) digestive physiology and carbohydrate metabolism.

PubMed

Ricigliano, Vincent A; Fitz, William; Copeland, Duan C; Mott, Brendon M; Maes, Patrick; Floyd, Amy S; Dockstader, Arnold; Anderson, Kirk E

2017-10-01

Carbohydrate-active enzymes play an important role in the honey bee (Apis mellifera) due to its dietary specialization on plant-based nutrition. Secretory glycoside hydrolases (GHs) produced in worker head glands aid in the processing of floral nectar into honey and are expressed in accordance with age-based division of labor. Pollen utilization by the honey bee has been investigated in considerable detail, but little is known about the metabolic fate of indigestible carbohydrates and glycosides in pollen biomass. Here, we demonstrate that pollen consumption stimulates the hydrolysis of sugars that are toxic to the bee (xylose, arabinose, mannose). GHs produced in the head accumulate in the midgut and persist in the hindgut that harbors a core microbial community composed of approximately 10 8 bacterial cells. Pollen consumption significantly impacted total and specific bacterial abundance in the digestive tract. Bacterial isolates representing major fermentative gut phylotypes exhibited primarily membrane-bound GH activities that may function in tandem with soluble host enzymes retained in the hindgut. Additionally, we found that plant-originating β-galactosidase activity in pollen may be sufficient, in some cases, for probable physiological activity in the gut. These findings emphasize the potential relative contributions of host, bacteria, and pollen enzyme activities to carbohydrate breakdown, which may be tied to gut microbiome dynamics and associated host nutrition. © 2017 Wiley Periodicals, Inc.

Prebiotics: why definitions matter

PubMed Central

Hutkins, Robert W; Krumbeck, Janina A; Bindels, Laure B; Cani, Patrice D; Fahey, George; Goh, Yong Jun; Hamaker, Bruce; Martens, Eric C; Mills, David A; Rastal, Robert A; Vaughan, Elaine; Sanders, Mary Ellen

2015-01-01

The prebiotic concept was introduced twenty years ago, and despite several revisions to the original definition, the scientific community has continued to debate what it means to be a prebiotic. How prebiotics are defined is important not only for the scientific community, but also for regulatory agencies, the food industry, consumers and healthcare professionals. Recent developments in community-wide sequencing and glycomics have revealed that more complex interactions occur between putative prebiotic substrates and the gut microbiota than previously considered. A consensus among scientists on the most appropriate definition of a prebiotic is necessary to enable continued use of the term. PMID:26431716

Very low-carbohydrate versus isocaloric high-carbohydrate diet in dietary obese rats.

PubMed

Axen, Kathleen V; Axen, Kenneth

2006-08-01

The effects of a very low-carbohydrate (VLC), high-fat (HF) dietary regimen on metabolic syndrome were compared with those of an isocaloric high-carbohydrate (HC), low-fat (LF) regimen in dietary obese rats. Male Sprague-Dawley rats, made obese by 8 weeks ad libitum consumption of an HF diet, developed features of the metabolic syndrome vs. lean control (C) rats, including greater visceral, subcutaneous, and hepatic fat masses, elevated plasma cholesterol levels, impaired glucose tolerance, and fasting and post-load insulin resistance. Half of the obese rats (VLC) were then fed a popular VLC-HF diet (Weeks 9 and 10 at 5% and Weeks 11 to 14 at 15% carbohydrate), and one-half (HC) were pair-fed an HC-LF diet (Weeks 9 to 14 at 60% carbohydrate). Energy intakes of pair-fed VLC and HC rats were less than C rats throughout Weeks 9 to 14. Compared with HC rats, VLC rats exhibited impaired insulin and glycemic responses to an intraperitoneal glucose load at Week 10 and lower plasma triacylglycerol levels but retarded loss of hepatic, retroperitoneal, and total body fat at Week 14. VLC, HC, and C rats no longer differed in body weight, plasma cholesterol, glucose tolerance, or fasting insulin resistance at Week 14. Progressive decreases in fasting insulin resistance in obese groups paralleled concomitant reductions in hepatic, retroperitoneal, and total body fat. When energy intake was matched, the VLC-HF diet provided no advantage in weight loss or in improving those components of the metabolic syndrome induced by dietary obesity and may delay loss of hepatic and visceral fat as compared with an HC-LF diet.

The low-carbohydrate diet and cardiovascular risk factors: Evidence from epidemiologic studies

PubMed Central

Hu, T.; Bazzano, L. A.

2015-01-01

Aims Obesity is an important public health issue because of its high prevalence and concomitant increase in risk of cardiovascular diseases. Low carbohydrate diets are popular for weight loss and weight management but are not recommended in leading guidelines due to the perception that increases in dietary fat intake may lead to an adverse cardiovascular risk profile. To clarify the effects of a low-carbohydrate diet for weight loss on cardiovascular disease risk factors as compared to a low fat diet for weight loss, we systematically reviewed data from randomized controlled clinical trials and large observational studies. Data synthesis We searched the MEDLINE database (Jan 1966–Nov 2013) to identify studies that examined a low-carbohydrate diet as compared to a low-fat diet for weight loss or the improvement of cardiovascular disease risk factors. Conclusions Recent randomized controlled trials document that low-carbohydrate diets not only decrease body weight but also improve cardiovascular risk factors. In light of this evidence from randomized controlled trials, dietary guidelines should be re-visited advocating a healthy low carbohydrate dietary pattern as an alternative dietary strategy for the prevention of obesity and cardiovascular disease risk factors. PMID:24613757

Change in food cravings, food preferences, and appetite during a low-carbohydrate and low-fat diet

PubMed Central

Martin, C. K.; Rosenbaum, D.; Han, H.; Geiselman, P.; Wyatt, H.; Hill, J.; Brill, C.; Bailer, B.; Miller, B. V.; Stein, R.; Klein, S.; Foster, Gard D.

2011-01-01

The study objective was to evaluate the effect of prescribing a low-carbohydrate diet (LCD) and a low-fat diet (LFD) on food cravings, food preferences, and appetite. Obese adults were randomly assigned to a LCD (n=134) or a LFD (n=136) for two years. Cravings for specific types of foods (sweets, high-fats, fast-food fats, carbohydrates/starches); preferences for high-sugar, high-carbohydrate, and low-carbohydrate/high-protein foods; and appetite were measured during the trial and evaluated during this secondary analysis of trial data. Differences between the LCD and LFD on change in outcome variables were examined with mixed linear models. Compared to the LFD, the LCD had significantly larger decreases in cravings for carbohydrates/starches and preferences for high-carbohydrate and high-sugar foods. The LCD group reported being less bothered by hunger compared to the LFD group. Compared to the LCD group, the LFD group had significantly larger decreases in cravings for high-fat foods and preference for low-carbohydrate/high-protein foods. Men had larger decreases in appetite ratings compared to women. Prescription of diets that promoted restriction of specific types of foods resulted in decreased cravings and preferences for the foods that were targeted for restriction. The results also indicate that the LCD group was less bothered by hunger compared to the LFD group and that men had larger reductions in appetite compared to women. PMID:21494226

Manipulation of Muscle Glycogen Concentrations Using High and Low Carbohydrate Diets and Exercise

DTIC Science & Technology

1987-08-01

high in carbohydrates in the form of simple sugars (i.e., sucrose, fructose , lactose) and complex carbohydrates (i.e., starches, dietary fiber...AD-A 187 732 REPORT NO T32-87 MANIPULATION OF MUSCLE GLYCOGEN CONCENTRATIONS USING HIGH AND LOW CARBOHYDRATE DIETS AND EXERCISE U S ARMY RESEARCH...Muscle Glycogen Concentrations Using High and Low Carbohydrate Diets and Exercise 12. PERSONAL AUTHOR(S) Buchbinder, J., Pocost, J., Hodgess, L., Roche

Effect of DHA supplementation on digestible starch utilization by rainbow trout.

PubMed

Tapia-Salazar, M; Bureau, W; Panserat, S; Corraze, G; Bureau, D P

2006-01-01

Rainbow trout has a limited ability to utilize digestible carbohydrates efficiently. Trout feeds generally contain high levels of DHA, a fatty acid known to inhibit a number of glycolytic and lipogenic enzymes in animals. A study was conducted to determine whether carbohydrate utilization by rainbow trout might be affected by dietary DHA level. Two low-carbohydrate (<4 % digestible carbohydrate) basal diets were formulated to contain 1 (adequate) or 4 (excess) g/100 g DHA diet respectively. The two basal diets were diluted with increasing levels of digestible starch (0 %, 10 %, 20 % and 30 %, respectively) to produce eight diets. These diets were fed to fish for 12 weeks at 15 degrees C according to a pair-fed protocol that consisted of feeding the same amount of basal diet but different amounts of starch. Live weight, N and lipid gains, hepatic glycogen and plasma glucose values significantly increased, whereas feed efficiency (gain:feed) significantly decreased, with increasing starch intake (P<0.05). The retention efficiency of N (N gain/digestible N intake) improved with starch supplementation but was not affected by DHA level (P>0.05). Starch increased the activity of glucokinase, pyruvate kinase, glucose 6-phosphate dehydrogenase and fatty acid synthase (P<0.05) but did not affect hexokinase and malic enzyme activity. DHA had no effect on growth but increased plasma glucose and reduced carcass lipid and liver glycogen contents (P<0.05). Glycolytic and lipogenic enzymes were not affected by DHA level, except for pyruvate kinase, which was reduced by increasing DHA level. These results suggest only a marginal effect of dietary DHA on the ability of fish to utilize carbohydrate.

Potential of probiotics, prebiotics and synbiotics for management of colorectal cancer

PubMed Central

Raman, Maya; Ambalam, Padma; Kondepudi, Kanthi Kiran; Pithva, Sheetal; Kothari, Charmy; Patel, Arti T.; Purama, Ravi Kiran; Dave, J.M.; Vyas, B.R.M.

2013-01-01

Colorectal Cancer (CRC) is the second leading cause of cancer-related mortality and is the fourth most common malignant neoplasm in USA. Escaping apoptosis and cell mutation are the prime hallmarks of cancer. It is apparent that balancing the network between DNA damage and DNA repair is critical in preventing carcinogenesis. One-third of cancers might be prevented by nutritious healthy diet, maintaining healthy weight and physical activity. In this review, an attempt is made to abridge the role of carcinogen in colorectal cancer establishment and prognosis, where special attention has been paid to food-borne mutagens and functional role of beneficial human gut microbiome in evading cancer. Further the significance of tailor-made prebiotics, probiotics and synbiotics in cancer management by bio-antimutagenic and desmutagenic activity has been elaborated. Probiotic bacteria are live microorganisms that, when administered in adequate amounts, confer a healthy benefit on the host. Prebiotics are a selectively fermentable non-digestible oligosaccharide or ingredient that brings specific changes, both in the composition and/or activity of the gastrointestinal microflora, conferring health benefits. Synbiotics are a combination of probiotic bacteria and the growth promoting prebiotic ingredients that purport “synergism.” PMID:23511582

Transcriptional Analysis of Prebiotic Uptake and Catabolism by Lactobacillus acidophilus NCFM

PubMed Central

Andersen, Joakim Mark; Barrangou, Rodolphe; Hachem, Maher Abou; Lahtinen, Sampo J.; Goh, Yong-Jun; Svensson, Birte; Klaenhammer, Todd R.

2012-01-01

The human gastrointestinal tract can be positively modulated by dietary supplementation of probiotic bacteria in combination with prebiotic carbohydrates. Here differential transcriptomics and functional genomics were used to identify genes in Lactobacillus acidophilus NCFM involved in the uptake and catabolism of 11 potential prebiotic compounds consisting of α- and β- linked galactosides and glucosides. These oligosaccharides induced genes encoding phosphoenolpyruvate-dependent sugar phosphotransferase systems (PTS), galactoside pentose hexuronide (GPH) permease, and ATP-binding cassette (ABC) transporters. PTS systems were upregulated primarily by di- and tri-saccharides such as cellobiose, isomaltose, isomaltulose, panose and gentiobiose, while ABC transporters were upregulated by raffinose, Polydextrose, and stachyose. A single GPH transporter was induced by lactitol and galactooligosaccharides (GOS). The various transporters were associated with a number of glycoside hydrolases from families 1, 2, 4, 13, 32, 36, 42, and 65, involved in the catabolism of various α- and β-linked glucosides and galactosides. Further subfamily specialization was also observed for different PTS-associated GH1 6-phospho-β-glucosidases implicated in the catabolism of gentiobiose and cellobiose. These findings highlight the broad oligosaccharide metabolic repertoire of L. acidophilus NCFM and establish a platform for selection and screening of both probiotic bacteria and prebiotic compounds that may positively influence the gastrointestinal microbiota. PMID:23028535

Energy utilization of a low carbohydrate diet fed genetically obese rats and mice.

PubMed

Thenen, S W; Mayer, J

1977-02-01

Genetically obese Zucker rats, ob/ob mice and non-obese littermates were fed low carbohydrate (2%, 48%, and 50% of energy as carbohydrate, protein, and fat, respectively) and control (60%, 19%, and 21%, as carobhydrate, protein, and fat) diets. The oxidation of the energy components of these diets was measured by adding D-[U-14C]glucose, L-[U-14C]glutamic acid, and glyceryl tri-[1-14C]oleate to test meals given intragastrically and collecting respiratory CO2 for 4 hours. The animals responded to the low carbohydrate diet by oxidizing less glucose and more glutamic acid, but these amounts were proportional to dietary carbohydrate and protein composition, In contrast, the animals oxidized both higher amounts and percentages of glyceryl trioleate when fed the low carbohydrate diet. Obese Zucker rats oxidized less fat than non-obese rats when fed both diets, while obese mice oxidized fat to the same extent as non-obese mice. Feeding the low carbohydrate diet significantly increased body weight in the obese mice, but not in obese rats and non-obese mice and rats. The effect of obesity and the low carbohydrate diet on food intake, serum glucose and lipid values and CO2 production are also reported.

Comparative nutrient digestibility of arctic foxes (Alopex lagopus) on Svalbard and farm-raised blue foxes (Alopex lagopus).

PubMed

Ahlstrøm, Øystein; Fuglei, Eva; Mydland, Liv Torunn

2003-01-01

Arctic foxes from Svalbard (n=4) and farmed blue foxes (n=4) was used in a digestibility experiment with a high-carbohydrate feed to add more information to the nutritional physiology of the arctic fox, and to compare its digestive capacity with that of the farmed blue fox. The arctic fox has a diet containing mainly protein and fat from mammals and birds, while farmed blue foxes have been exposed to an omnivorous dietary regime for more than 80 generations. The experiment showed in general no difference in digestive capacity for protein and fat between the foxes (P>0.05), but for carbohydrates, including starch and glucose, the blue fox revealed higher digestibility values. The superior digestive capacity for carbohydrates in blue fox might be a result of a long-term selection of animals digesting dietary carbohydrates more efficiently, or that an early age exposition to dietary carbohydrates has given permanent improvement of the carbohydrate digestion in the gut.

The effect of free and protected oils on the digestion of dietary carbohydrates between the mouth and duodenum of sheep.

PubMed

McAllan, A B; Knight, R; Sutton, J D

1983-05-01

Sheep fitted with rumen and re-entrant duodenal cannulas were given diets of approximately 200 g hay and 400 g concentrate mixture alone, or supplemented daily with 40 g linseed or coconut oils free or protected with formaldehyde-casein in a 5 x 5 Latin-square arrangement. Chromic oxide paper was given as a marker at feeding time and passage to the duodenum of neutral-detergent fibre (NDF) and different sugars were estimated from the values for constituent:marker at the duodenum. Contributions of microbial carbohydrates to these flows were estimated from amounts of RNA present. The carbohydrate composition of mixed rumen bacteria from sheep rumen digesta were similar regardless of diet. Of the sugars entering the duodenum all the rhamnose and ribose and 0.51, 0.24 and 0.35 of the mannose, galactose and starch-glucose respectively, were contributed by the microbes. Virtually all the arabinose, xylose and cellulose-glucose were contributed by the diet. For sheep receiving the basal ration, coefficients of digestibility between mouth and duodenum, corrected where necessary for microbial contribution, were 0.95, 0.66, 0.67, 0.62, 0.45 and 0.51 for starch-glucose, mannose, arabinose, galactose, xylose and cellulose-glucose respectively. Corresponding values when free-oil-supplemented diets were given were 0.95, 0.55, 0.38, 0.55, 0.01 and -0.02 respectively. Values for diets supplemented with linseed oil or coconut oil did not differ significantly. Addition of protected oils to the basal feed also resulted in depressed digestibilities of dietary structural sugars but to a far lesser extent than those observed with the free oils. Apparent digestibility of NDF was altered in the same direction as those of the main structural sugars, averaging 0.50, 0.17 and 0.29 in animals receiving the basal, free-oil-supplemented or protected-oil-supplemented diets respectively. The reasons for the difference between NDF and discrete carbohydrate analytical totals are discussed.

Chili Peppers, Curcumins, and Prebiotics in Gastrointestinal Health and Disease.

PubMed

Patcharatrakul, Tanisa; Gonlachanvit, Sutep

2016-04-01

There is growing evidence for the role of several natural products as either useful agents or adjuncts in the management of functional GI disorders (FGIDs). In this review, we examine the medical evidence for three such compounds: chili, a culinary spice; curcumin, another spice and active derivative of a root bark; and prebiotics, which are nondigestible food products. Chili may affect the pathogenesis of abdominal pain especially in functional dyspepsia and cause other symptoms. It may have a therapeutic role in FGIDs through desensitization of transient receptor potential vanilloid-1 receptor. Curcumin, the active ingredient of turmeric rhizome, has been shown in several preclinical studies and uncontrolled clinical trials as having effects on gut inflammation, gut permeability and the brain-gut axis, especially in FGIDs. Prebiotics, the non-digestible food ingredients in dietary fiber, may serve as nutrients and selectively stimulate the growth and/or activity of certain colonic bacteria. The net effect of this change on colonic microbiota may lead to the production of acidic metabolites and other compounds that help to reduce the production of toxins and suppress the growth of harmful or disease-causing enteric pathogens. Although some clinical benefit in IBS has been shown, high dose intake of prebiotics may cause more bloating from bacterial fermentation.

Comparative Effects of Low-Carbohydrate High-Protein Versus Low-Fat Diets on the Kidney

PubMed Central

Ogden, Lorraine G.; Foster, Gary D.; Klein, Samuel; Stein, Richard; Miller, Bernard; Hill, James O.; Brill, Carrie; Bailer, Brooke; Rosenbaum, Diane R.; Wyatt, Holly R.

2012-01-01

Summary Background and objectives Concerns exist about deleterious renal effects of low-carbohydrate high-protein weight loss diets. This issue was addressed in a secondary analysis of a parallel randomized, controlled long-term trial. Design, setting, participants, and measurements Between 2003 and 2007, 307 obese adults without serious medical illnesses at three United States academic centers were randomly assigned to a low-carbohydrate high-protein or a low-fat weight-loss diet for 24 months. Main outcomes included renal filtration (GFR) indices (serum creatinine, cystatin C, creatinine clearance); 24-hour urinary volume; albumin; calcium excretion; and serum solutes at 3, 12, and 24 months. Results Compared with the low-fat diet, low-carbohydrate high-protein consumption was associated with minor reductions in serum creatinine (relative difference, −4.2%) and cystatin C (−8.4%) at 3 months and relative increases in creatinine clearance at 3 (15.8 ml/min) and 12 (20.8 ml/min) months; serum urea at 3 (14.4%), 12 (9.0%), and 24 (8.2%) months; and 24-hour urinary volume at 12 (438 ml) and 24 (268 ml) months. Urinary calcium excretion increased at 3 (36.1%) and 12 (35.7%) months without changes in bone density or clinical presentations of new kidney stones. Conclusions In healthy obese individuals, a low-carbohydrate high-protein weight-loss diet over 2 years was not associated with noticeably harmful effects on GFR, albuminuria, or fluid and electrolyte balance compared with a low-fat diet. Further follow-up is needed to determine even longer-term effects on kidney function. PMID:22653255

Effects of low carbohydrate diets on energy and nitrogen balance and body composition in rats depend on dietary protein-to-energy ratio.

PubMed

Frommelt, Lena; Bielohuby, Maximilian; Menhofer, Dominik; Stoehr, Barbara J M; Bidlingmaier, Martin; Kienzle, Ellen

2014-01-01

Truly ketogenic rodent diets are low in carbohydrates but also low in protein. The aim of this study was to differentiate effects of ketosis, low carbohydrate (LC) and/or low-protein intake on energy and nitrogen metabolism. We studied the nitrogen balance of rats fed LC diets with varying protein contents: LC diets consisted of 75/10, 65/20 and 55/30 percent of fat to protein (dry matter), respectively, and were iso-energetically pair-fed to a control (chow) diet to 12-wk-old male Wistar rats (n = 6 per diet). Previous studies demonstrated only LC75/10 was truly ketogenic. Food, fecal, and urine samples, as well as carcasses were collected and analyzed for heat of combustion and nitrogen (Kjeldahl method). Blood samples were analyzed for plasma protein, albumin, and triacylglycerol. All LC groups displayed less body weight gain, and the degree of reduction was inversely related to digestible crude protein intake (daily weight gain compared with chow: LC75/10: -50%; LC55/30: -20%). Nitrogen excretion by urine was related to digestible protein intake (chow: 0.23 ± 0.02 g nitrogen/d; LC75/10: 0.05 ± 0.01 g nitrogen/d). Renal energy excretion was closely associated with intake of digestible crude protein (r = 0.697) and renal nitrogen excretion (r = 0.769). Energy-to-nitrogen ratio in urine was nearly doubled with LC75/10 compared with all other groups. Total body protein was highest with chow and lowest with LC75/10. Rats fed with LC75/10 displayed features of protein deficiency (reduced growth and nitrogen balance, hypoproteinemia, depletion of body protein, and increased body and liver fat), whereas the effects with the non-ketogenic diets LC65/20 and LC55/30 were less pronounced. These results suggest that truly ketogenic LC diets in growing rats are LC diets that are also deficient in protein for growth. Copyright © 2014 Elsevier Inc. All rights reserved.

Carbohydrate catabolic flexibility in the mammalian intestinal commensal Lactobacillus ruminis revealed by fermentation studies aligned to genome annotations

PubMed Central

2011-01-01

Background Lactobacillus ruminis is a poorly characterized member of the Lactobacillus salivarius clade that is part of the intestinal microbiota of pigs, humans and other mammals. Its variable abundance in human and animals may be linked to historical changes over time and geographical differences in dietary intake of complex carbohydrates. Results In this study, we investigated the ability of nine L. ruminis strains of human and bovine origin to utilize fifty carbohydrates including simple sugars, oligosaccharides, and prebiotic polysaccharides. The growth patterns were compared with metabolic pathways predicted by annotation of a high quality draft genome sequence of ATCC 25644 (human isolate) and the complete genome of ATCC 27782 (bovine isolate). All of the strains tested utilized prebiotics including fructooligosaccharides (FOS), soybean-oligosaccharides (SOS) and 1,3:1,4-β-D-gluco-oligosaccharides to varying degrees. Six strains isolated from humans utilized FOS-enriched inulin, as well as FOS. In contrast, three strains isolated from cows grew poorly in FOS-supplemented medium. In general, carbohydrate utilisation patterns were strain-dependent and also varied depending on the degree of polymerisation or complexity of structure. Six putative operons were identified in the genome of the human isolate ATCC 25644 for the transport and utilisation of the prebiotics FOS, galacto-oligosaccharides (GOS), SOS, and 1,3:1,4-β-D-Gluco-oligosaccharides. One of these comprised a novel FOS utilisation operon with predicted capacity to degrade chicory-derived FOS. However, only three of these operons were identified in the ATCC 27782 genome that might account for the utilisation of only SOS and 1,3:1,4-β-D-Gluco-oligosaccharides. Conclusions This study has provided definitive genome-based evidence to support the fermentation patterns of nine strains of Lactobacillus ruminis, and has linked it to gene distribution patterns in strains from different sources. Furthermore

Atkins and other low-carbohydrate diets: hoax or an effective tool for weight loss?

PubMed

Astrup, Arne; Meinert Larsen, Thomas; Harper, Angela

The Atkins diet books have sold more than 45 million copies over 40 years, and in the obesity epidemic this diet and accompanying Atkins food products are popular. The diet claims to be effective at producing weight loss despite ad-libitum consumption of fatty meat, butter, and other high-fat dairy products, restricting only the intake of carbohydrates to under 30 g a day. Low-carbohydrate diets have been regarded as fad diets, but recent research questions this view. A systematic review of low-carbohydrate diets found that the weight loss achieved is associated with the duration of the diet and restriction of energy intake, but not with restriction of carbohydrates. Two groups have reported longer-term randomised studies that compared instruction in the low-carbohydrate diet with a low-fat calorie-reduced diet in obese patients (N Engl J Med 2003; 348: 2082-90; Ann Intern Med 2004; 140: 778-85). Both trials showed better weight loss on the low-carbohydrate diet after 6 months, but no difference after 12 months. WHERE NEXT?: The apparent paradox that ad-libitum intake of high-fat foods produces weight loss might be due to severe restriction of carbohydrate depleting glycogen stores, leading to excretion of bound water, the ketogenic nature of the diet being appetite suppressing, the high protein-content being highly satiating and reducing spontaneous food intake, or limited food choices leading to decreased energy intake. Long-term studies are needed to measure changes in nutritional status and body composition during the low-carbohydrate diet, and to assess fasting and postprandial cardiovascular risk factors and adverse effects. Without that information, low-carbohydrate diets cannot be recommended.

Dietary Intervention for Overweight and Obese Adults: Comparison of Low-Carbohydrate and Low-Fat Diets. A Meta-Analysis

PubMed Central

Sackner-Bernstein, Jonathan; Kanter, David; Kaul, Sanjay

2015-01-01

Background Reduced calorie, low fat diet is currently recommended diet for overweight and obese adults. Prior data suggest that low carbohydrate diets may also be a viable option for those who are overweight and obese. Purpose Compare the effects of low carbohydrate versus low fats diet on weight and atherosclerotic cardiovascular disease risk in overweight and obese patients. Data Sources Systematic literature review via PubMed (1966–2014). Study Selection Randomized controlled trials with ≥8 weeks follow up, comparing low carbohydrate (≤120gm carbohydrates/day) and low fat diet (≤30% energy from fat/day). Data Extraction Data were extracted and prepared for analysis using double data entry. Prior to identification of candidate publications, the outcomes of change in weight and metabolic factors were selected as defined by Cochrane Collaboration. Assessment of the effects of diets on predicted risk of atherosclerotic cardiovascular disease risk was added during the data collection phase. Data Synthesis 1797 patients were included from 17 trials with <1 year follow up in 12. Compared with low fat diet, low carbohydrate was associated with significantly greater reduction in weight (Δ = -2.0 kg, 95% CI: -3.1, -0.9) and significantly lower predicted risk of atherosclerotic cardiovascular disease events (p<0.03). Frequentist and Bayesian results were concordant. The probability of greater weight loss associated with low carbohydrate was >99% while the reduction in predicted risk favoring low carbohydrate was >98%. Limitations Lack of patient-level data and heterogeneity in dropout rates and outcomes reported. Conclusions This trial-level meta-analysis of randomized controlled trials comparing LoCHO diets with LoFAT diets in strictly adherent populations demonstrates that each diet was associated with significant weight loss and reduction in predicted risk of ASCVD events. However, LoCHO diet was associated with modest but significantly greater improvements in

Common Prairie feeds with different soluble and insoluble fractions used for CPM diet formulation in dairy cattle: impact of carbohydrate-protein matrix structure on protein and other primary nutrient digestion.

PubMed

Peng, Quanhui; Wang, Zhisheng; Zhang, Xuewei; Yu, Peiqiang

2014-01-01

An experiment was conducted to investigate the relationship of carbohydrates molecular spectral characteristics to rumen degradability of primary nutrients in Prairie feeds in dairy cattle. In total, 12 different types of feeds were selected, each type of feed was from three different source with total 37 samples. Six types of them were energy-sourced feeds and the others were protein-sourced feeds. The carbohydrates molecular spectral intensity of various functional groups were collected using Fourier transform infrared attenuated total reflectance (ATR-FT/IR) spectroscopy. In the in situ study, the results showed that the rumen digestibility and digestible fractions of primary nutrients (DM, OM, NCP, and CP) were significantly different (P<0.05) among the feeds. The spectral bands features were significantly different (P<0.05) among the feeds. Spectral intensities of A_Cell, H_1415 and H_1370 were weakly positively correlated with in situ rumen digestibility and digestible fractions of DM, OM and NCP. Spectral intensities of H_1150, H_1015, A_1, and A_3 were weakly negatively associated with in situ rumen degradation of CP. Spectral intensities of A_1240 and H_1240, mainly associated with cellulosic compounds, were correlated with rumen CP degradation. The multiple regression analysis demonstrated that the spectral intensities of A_3 and H_1415 played the most important role and could be used as a potential tool to predict rumen protein degradation of feeds in dairy cattle. In conclusion, this study showed that the carbohydrates as a whole have an effect on protein rumen degradation, rather than cellulose alone, indicating carbohydrate-protein matrix structure impact protein utilization in dairy cattle. The non-invasive molecular spectral technique (ATR-FT/IR) could be used as a rapid potential tool to predict rumen protein degradation of feedstuffs by using molecular spectral bands intensities in carbohydrate fingerprint region. Copyright © 2013 Elsevier B

Differential effects of low-carbohydrate and low-fat diets on inflammation and endothelial function in diabetes.

PubMed

Davis, Nichola J; Crandall, Jill P; Gajavelli, Srikanth; Berman, Joan W; Tomuta, Nora; Wylie-Rosett, Judith; Katz, Stuart D

2011-01-01

To characterize acute (postprandial) and chronic (after a 6-month period of weight loss) effects of a low-carbohydrate vs. a low-fat diet on subclinical markers of cardiovascular disease (CVD) in adults with type 2 diabetes. At baseline and 6 months, measures of C-reactive protein (CRP), interleukin-6 (IL-6), soluble intercellular adhesion molecule (sICAM) and soluble E-selectin were obtained from archived samples (n = 51) of participants randomized in a clinical trial comparing a low-carbohydrate and a low-fat diet. In a subset of participants (n = 27), postprandial measures of these markers were obtained 3 h after a low-carbohydrate or low-fat liquid meal. Endothelial function was also measured by reactive hyperemic peripheral arterial tonometry during the meal test. Paired t tests and unpaired t tests compared within- and between-group changes. There were no significant differences observed in postprandial measures of inflammation or endothelial function. After 6 months, CRP (mean ± S.E.) decreased in the low-fat arm from 4.0 ± 0.77 to 3.0 ± 0.77 (P = .01). In the low-carbohydrate arm, sICAM decreased from 234 ± 22 to 199 ± 23 (P = .001), and soluble E-selectin decreased from 93 ± 10 to 82 ± 10 (P = .05.) A significant correlation between change in high-density lipoprotein and change in soluble E-selectin (r = -0.33, P = .04) and with the change in ICAM (r = -0.43, P = .01) was observed. Low-carbohydrate and low-fat diets both have beneficial effects on CVD markers. There may be different mechanisms through which weight loss with these diets potentially reduces CVD risk. Copyright © 2011 Elsevier Inc. All rights reserved.

Glycemic index and glycemic load of carbohydrates in the diabetes diet.

PubMed

Marsh, Kate; Barclay, Alan; Colagiuri, Stephen; Brand-Miller, Jennie

2011-04-01

Medical nutrition therapy is the first line of treatment for the prevention and management of type 2 diabetes and plays an essential part in the management of type 1 diabetes. Although traditionally advice was focused on carbohydrate quantification, it is now clear that both the amount and type of carbohydrate are important in predicting an individual's glycemic response to a meal. Diets based on carbohydrate foods that are more slowly digested, absorbed, and metabolized (i.e., low glycemic index [GI] diets) have been associated with a reduced risk of type 2 diabetes and cardiovascular disease, whereas intervention studies have shown improvements in insulin sensitivity and glycated hemoglobin concentrations in people with diabetes following a low GI diet. Research also suggests that low GI diets may assist with weight management through effects on satiety and fuel partitioning. These findings, together with the fact that there are no demonstrated negative effects of a low GI diet, suggest that the GI should be an important consideration in the dietary management and prevention of diabetes.

Metabolic response to high-carbohydrate and low-carbohydrate meals in a nonhuman primate model.

PubMed

Fabbrini, Elisa; Higgins, Paul B; Magkos, Faidon; Bastarrachea, Raul A; Voruganti, V Saroja; Comuzzie, Anthony G; Shade, Robert E; Gastaldelli, Amalia; Horton, Jay D; Omodei, Daniela; Patterson, Bruce W; Klein, Samuel

2013-02-15

We established a model of chronic portal vein catheterization in an awake nonhuman primate to provide a comprehensive evaluation of the metabolic response to low-carbohydrate/high-fat (LCHF; 20% carbohydrate and 65% fat) and high-carbohydrate/low-fat (HCLF; 65% carbohydrate and 20% fat) meal ingestion. Each meal was given 1 wk apart to five young adult (7.8 ± 1.3 yr old) male baboons. A [U-¹³C]glucose tracer was added to the meal, and a [6,6-²H₂]glucose tracer was infused systemically to assess glucose kinetics. Plasma areas under the curve (AUCs) of glucose, insulin, and C-peptide in the femoral artery and of glucose and insulin in the portal vein were higher (P ≤ 0.05) after ingestion of the HCLF compared with the LCHF meal. Compared with the LCHF meal, the rate of appearance of ingested glucose into the portal vein and the systemic circulation was greater after the HCLF meal (P < 0.05). Endogenous glucose production decreased by ∼40% after ingestion of the HCLF meal but was not affected by the LCHF meal (P < 0.05). Portal vein blood flow increased (P < 0.001) to a similar extent after consumption of either meal. In conclusion, a LCHF diet causes minimal changes in the rate of glucose appearance in both portal and systemic circulations, does not affect the rate of endogenous glucose production, and causes minimal stimulation of C-peptide and insulin. These observations demonstrate that LCHF diets cause minimal perturbations in glucose homeostasis and pancreatic β-cell activity.

Asphalt, water, and the prebiotic synthesis of ribose, ribonucleosides, and RNA.

PubMed

Benner, Steven A; Kim, Hyo-Joong; Carrigan, Matthew A

2012-12-18

RNA has been called a "prebiotic chemist's nightmare" because of its combination of large size, carbohydrate building blocks, bonds that are thermodynamically unstable in water, and overall intrinsic instability. However, a discontinuous synthesis model is well-supported by experimental work that might produce RNA from atmospheric CO(2), H(2)O, and N(2). For example, electrical discharge in such atmospheres gives formaldehyde (HCHO) in large amounts and glycolaldehyde (HOCH(2)CHO) in small amounts. When rained into alkaline aquifers generated by serpentinizing rocks, these substances were undoubtedly converted to carbohydrates including ribose. Likewise, atmospherically generated HCN was undoubtedly converted in these aquifers to formamide and ammonium formate, precursors for RNA nucleobases. Finally, high reduction potentials maintained by mantle-derived rocks and minerals would allow phosphite to be present in equilibrium with phosphate, mobilizing otherwise insoluble phosphorus for the prebiotic synthesis of phosphite and phosphate esters after oxidation. So why does the community not view this discontinuous synthesis model as compelling evidence for the RNA-first hypothesis for the origin of life? In part, the model is deficient because no experiments have joined together those steps without human intervention. Further, many steps in the model have problems. Some are successful only if reactive compounds are presented in a specific order in large amounts. Failing controlled addition, the result produces complex mixtures that are inauspicious precursors for biology, a situation described as the "asphalt problem". Many bonds in RNA are thermodynamically unstable with respect to hydrolysis in water, creating a "water problem". Finally, some bonds in RNA appear to be "impossible" to form under any conditions considered plausible for early Earth. To get a community-acceptable "RNA first" model for the origin of life, the discontinuous synthesis model must be

Probiotics, prebiotics infant formula use in preterm or low birth weight infants: a systematic review

PubMed Central

2012-01-01

Background Previous reviews (2005 to 2009) on preterm infants given probiotics or prebiotics with breast milk or mixed feeds focused on prevention of Necrotizing Enterocolitis, sepsis and diarrhea. This review assessed if probiotics, prebiotics led to improved growth and clinical outcomes in formula fed preterm infants. Methods Cochrane methodology was followed using randomized controlled trials (RCTs) which compared preterm formula containing probiotic(s) or prebiotic(s) to conventional preterm formula in preterm infants. The mean difference (MD) and corresponding 95% confidence intervals (CI) were reported for continuous outcomes, risk ratio (RR) and corresponding 95% CI for dichotomous outcomes. Heterogeneity was assessed by visual inspection of forest plots and a chi2 test. An I2 test assessed inconsistencies across studies. I2> 50% represented substantial heterogeneity. Results Four probiotics studies (N=212), 4 prebiotics studies (N=126) were included. Probiotics: There were no significant differences in weight gain (MD 1.96, 95% CI: -2.64 to 6.56, 2 studies, n=34) or in maximal enteral feed (MD 35.20, 95% CI: -7.61 to 78.02, 2 studies, n=34), number of stools per day increased significantly in probiotic group (MD 1.60, 95% CI: 1.20 to 2.00, 1 study, n=20). Prebiotics: Galacto-oligosaccharide / Fructo-oligosaccharide (GOS/FOS) yielded no significant difference in weight gain (MD 0.04, 95% CI: -2.65 to 2.73, 2 studies, n=50), GOS/FOS yielded no significant differences in length gain (MD 0.01, 95% CI: -0.03 to 0.04, 2 studies, n=50). There were no significant differences in head growth (MD −0.01, 95% CI: -0.02 to 0.00, 2 studies, n=76) or age at full enteral feed (MD −0.79, 95% CI: -2.20 to 0.61, 2 studies, n=86). Stool frequency increased significantly in prebiotic group (MD 0.80, 95% CI: 0.48 to 1.1, 2 studies, n=86). GOS/FOS and FOS yielded higher bifidobacteria counts in prebiotics group (MD 2.10, 95% CI: 0.96 to 3.24, n=27) and (MD 0.48, 95% CI: 0

Comparison of efficacy of low-carbohydrate and low-fat diet education programs in non-alcoholic fatty liver disease: A randomized controlled study.

PubMed

Jang, Eun Chul; Jun, Dae Won; Lee, Seung Min; Cho, Yong Kyun; Ahn, Sang Bong

2018-02-01

Composition of macronutrients is important in non-alcoholic fatty liver disease (NAFLD). Diet education programs that mainly emphasize reducing fat consumption have been used for NAFLD patients. We compared the efficacy of conventional low-fat diet education with low-carbohydrate diet education in Korean NAFLD patients. One hundred and six NAFLD patients were randomly allocated to low-fat diet education or low-carbohydrate education groups for 8 weeks. Liver chemistry, liver / spleen ratio, and visceral fat using abdominal tomography were measured. Intrahepatic fat accumulation decreased significantly in the low-carbohydrate group compared to low-fat group (liver/spleen 0.85 vs. 0.92, P < 0.05). Normalization of ALT activity at week 8 was 38.5% for the low-carbohydrate and 16.7% for the low-fat group (P = 0.016). Not only liver enzyme, but also low density lipoprotein cholesterol and blood pressure levels significantly decreased in the low-carbohydrate group. Total energy intake was also further decreased in the low-carbohydrate group compared to the low-fat group. Although body weight changes were not different between the two groups, the carbohydrate group had a lower total abdominal fat amount. A low-carbohydrate diet program is more realistic and effective in reducing total energy intake and hepatic fat content in Korean NAFLD patients. This trial is registered with the National Research Institute of Health: KCT0000970 (https://cris.nih.go.kr/cris/index.jsp). © 2017 The Japan Society of Hepatology.

Overweight and diabetes prevention: is a low-carbohydrate-high-fat diet recommendable?

PubMed

Brouns, Fred

2018-03-14

In the past, different types of diet with a generally low-carbohydrate content (< 50-< 20 g/day) have been promoted, for weight loss and diabetes, and the effectiveness of a very low dietary carbohydrate content has always been a matter of debate. A significant reduction in the amount of carbohydrates in the diet is usually accompanied by an increase in the amount of fat and to a lesser extent, also protein. Accordingly, using the term "low carb-high fat" (LCHF) diet is most appropriate. Low/very low intakes of carbohydrate food sources may impact on overall diet quality and long-term effects of such drastic diet changes remain at present unknown. This narrative review highlights recent metabolic and clinical outcomes of studies as well as practical feasibility of low LCHF diets. A few relevant observations are as follows: (1) any diet type resulting in reduced energy intake will result in weight loss and related favorable metabolic and functional changes; (2) short-term LCHF studies show both favorable and less desirable effects; (3) sustained adherence to a ketogenic LCHF diet appears to be difficult. A non-ketogenic diet supplying 100-150 g carbohydrate/day, under good control, may be more practical. (4) There is lack of data supporting long-term efficacy, safety and health benefits of LCHF diets. Any recommendation should be judged in this light. (5) Lifestyle intervention in people at high risk of developing type 2 diabetes, while maintaining a relative carbohydrate-rich diet, results in long-term prevention of progression to type 2 diabetes and is generally seen as safe.

Effects of different sources of carbohydrates on intake, digestibility, chewing, and performance of Holstein dairy cows

PubMed Central

2014-01-01

To investigate the effects of different sources of carbohydrates on intake, digestibility, chewing, and performance, nine lactating Holstein dairy cows (day in milk= 100±21 d; body weight=645.7 ± 26.5 kg) were allotted to a 3 × 3 Latin square design at three 23-d periods. The three treatments included 34.91% (B), 18.87% (BC), and 18.86% (BB) barley that in treatment B was partially replaced with only corn or corn plus beet pulp in treatments BC and BB, respectively. The concentration of starch and neutral detergent soluble carbohydrate varied (22.2, 20.2, and 14.5; 13.6, 15.9, and 20.1% of DM in treatments B, BC, and BB, respectively). Cows in treatment BB showed a higher DMI and improved digestibility of DM, NDF, and EE compared with treatments B or BC. Ruminal pH was higher in cows fed on BB (6.83) compared with those that received B or BC treatments (6.62 and 6.73, respectively). A lower proportion of propionate accompanied the higher pH in the BB group; however, a greater proportion of acetate and acetate: propionate ratio was observed compared with cows fed either on the B or BC diet. Moreover, cows fed on the BB diet showed the lowest ruminal passage rate and longest ruminal and total retention time. Eating time did not differ among treatments, rumination time was greater among cows fed on the BB diet compared with the others, whereas total chewing activity was greater than those fed on BC, but similar to those fed on B. The treatments showed no effect on milk yield. Partially replacing barley with corn or beet pulp resulted in an increase in milk fat and a lower protein concentration. Changing dietary NFC with that of a different degradability thus altered intake, chewing activity, ruminal environment, retention time or passage rate, and lactation performance. The results of this study showed that beet pulp with a higher NDF and a detergent-soluble carbohydrate or pectin established a more consistent ruminal mat than barley and corn, thus resulting in

Adherence to low-carbohydrate and low-fat diets in relation to weight loss and cardiovascular risk factors.

PubMed

Hu, Tian; Yao, Lu; Reynolds, Kristi; Niu, Tianhua; Li, Shengxu; Whelton, Paul K; He, Jiang; Steffen, Lyn M; Bazzano, Lydia A

2016-03-01

A low-carbohydrate diet can reduce body weight and some cardiovascular disease (CVD) risk factors more than a low-fat diet, but differential adherence may play a role in these effects. Data were used from 148 adults who participated in a 12-month clinical trial examining the effect of a low-carbohydrate diet (<40 g/day) and a low-fat diet (<30% fat, <7% saturated fat) on weight and CVD risk factors. We compared attendance at counseling sessions, deviation from nutrient goals, urinary ketone presence, and composite scores representing the overall adherence based on the distribution of these individual indicators between two interventions. Composite scores were similar between the two groups. A one-interquartile-range increase in composite score representing better adherence to a low-carbohydrate diet was associated with 2.2 kg or 2.3 % greater weight loss, 1.1 greater reduction in percent fat mass, and 1.3 greater increase in proportion of lean mass. Indicators of adherence to a low-fat diet was not associated with changes in weight, fat mass or lean mass. Despite comparable adherence between groups, a low-carbohydrate diet was associated with greater reductions in body weight and improvement in body composition, while a low-fat diet was not associated with weight loss.

The role of lipid and carbohydrate digestive enzyme inhibitors in the management of obesity: a review of current and emerging therapeutic agents

PubMed Central

Tucci, Sonia A; Boyland, Emma J; Halford, Jason CG

2010-01-01

Obesity is a global epidemic associated with significant morbidity and mortality in adults and ill health in children. A proven successful approach in weight management has been the disruption of nutrient digestion, with orlistat having been used to treat obesity for the last 10 years. Although orlistat-induced weight loss remains modest, it produces meaningful reductions in risk factors for obesity-related conditions such as diabetes and cardiovascular disease. Moreover, this lipase inhibitor is free of the serious side effects that have dogged appetite-suppressing drugs. This success had driven investigation into new generation nutraceuticals, supplements and pharmaceutical agents that inhibit the breakdown of complex carbohydrates and fats within the gut. This review focuses on agents purported to inhibit intestinal enzymes responsible for macronutrient digestion. Except for some synthetic products, the majority of agents reviewed are either botanical extracts or bacterial products. Currently, carbohydrate digestion inhibitors are under development to improve glycemic control and these may also induce some weight loss. However, colonic fermentation induced side effects, such as excess gas production, remain an issue for these compounds. The α-glucosidase inhibitor acarbose, and the α-amylase inhibitor phaseolamine, have been used in humans with some promising results relating to weight loss. Nonetheless, few of these agents have made it into clinical studies and without any clinical proof of concept or proven efficacy it is unlikely any will enter the market soon. PMID:21437083

Effects of small peptides, probiotics, prebiotics, and synbiotics on growth performance, digestive enzymes, and oxidative stress in orange-spotted grouper, Epinephelus coioides, juveniles reared in artificial seawater

NASA Astrophysics Data System (ADS)

Wang, Tao; Cheng, Yongzhou; Chen, Xiaoyan; Liu, Zhaopu; Long, Xiaohua

2017-01-01

Aquaculture production efficiency may increase by using feed additives. This study investigated the effects of different dietary additives [w/w: 2% small peptides, 0.01% probiotics ( Bacillus licheniformis) and 0.2% prebiotics (inulin)] on growth performance, digestive enzyme activities, and oxidative stress in juvenile Epinephelus coioides reared in artificial seawater of two salt concentrations (13.5 vs. 28.5). Weight gain rate was significantly higher in fish fed the diet supplemented with small peptides, B. licheniformis, inulin, or synbiotics than that in fish fed the basal diet; the greatest weight gain rate was found in fish fed the small peptide treatment [56.0% higher than basal diet]. Higher feed efficiency was detected in fish fed the diet supplemented with small peptides than that of fish in the other dietary treatments. Total protease activity in the stomach and intestines was highest in fish fed the small peptide-treated diet, whereas lipase activity was highest in those fed synbiotics (combination of Bacillus licheniformis and inulin) than that in fish fed the other treatments. Antioxidant enzyme (total superoxide dismutase and catalase) activities and hepatic malondialdehyde content were higher in fish receiving the dietary supplements and maintained in artificial seawater containing 13.5 salinity compared with those in the control (28.5). Hepatic catalase activity in grouper fed the diets with small peptides or synbiotics decreased significantly compared with that in control fish. Overall, the three types of additives improved growth rate of juvenile grouper and digestive enzymes activities to varying degrees but did not effectively improve antioxidant capacity under low-salinity stress conditions.

Prebiotics and Bone.

PubMed

Whisner, Corrie M; Weaver, Connie M

2017-01-01

Recent advancements in food science have resulted in the extraction and synthesis of novel dietary fibers or prebiotics. Subsequently, great interest has emerged in developing strategies to improve metabolic conditions like osteoporosis by modulating the intestinal microbiome with fiber. Prebiotics have been shown to increase calcium absorption in the lower gut of both animals and humans as well as improve measures of bone mineral density and strength in rodent models. Fewer data are available in humans, but data from growing children and postmenopausal women suggest that prebiotics have both short- and long-term effects that beneficially affect bone turnover and mineral accretion in the skeleton. Currently, the exact mechanism by which these products elicit their effects on bone is poorly understood, but emerging data suggest that the gut microbiota may be involved in one or more direct and indirect pathways. The most well-accepted mechanism is through microbial fermentation of prebiotics which results in the production of short-chain fatty acids and a concomitant decrease in pH which increases the bioavailability of calcium in the colon. While other mechanisms may be eliciting a prebiotic effect on bone, the current data suggest that novel dietary fibers may be an affordable and effective method of maximizing mineral accretion in growing children and preventing bone loss in later years when osteoporosis is a greater risk. This chapter will discuss the dynamic role of prebiotics in bone health by discussing the current state of the art, addressing gaps in knowledge and their role in public health.

Antigenotoxic activity of lactic acid bacteria, prebiotics, and products of their fermentation against selected mutagens.

PubMed

Nowak, Adriana; Śliżewska, Katarzyna; Otlewska, Anna

2015-12-01

Dietary components such as lactic acid bacteria (LAB) and prebiotics can modulate the intestinal microbiota and are thought to be involved in the reduction of colorectal cancer risk. The presented study measured, using the comet assay, the antigenotoxic activity of both probiotic and non-probiotic LAB, as well as some prebiotics and the end-products of their fermentation, against fecal water (FW). The production of short chain fatty acids by the bacteria was quantified using HPLC. Seven out of the ten tested viable strains significantly decreased DNA damage induced by FW. The most effective of them were Lactobacillus mucosae 0988 and Bifidobacterium animalis ssp. lactis Bb-12, leading to a 76% and 80% decrease in genotoxicity, respectively. The end-products of fermentation of seven prebiotics by Lactobacillus casei DN 114-001 exhibited the strongest antigenotoxic activity against FW, with fermented inulin reducing genotoxicity by 75%. Among the tested bacteria, this strain produced the highest amounts of butyrate in the process of prebiotic fermentation, and especially from resistant dextrin (4.09 μM/mL). Fermented resistant dextrin improved DNA repair by 78% in cells pre-treated with 6.8 μM methylnitronitrosoguanidine (MNNG). Fermented inulin induced stronger DNA repair in cells pre-treated with mutagens (FW, 25 μM hydrogen peroxide, or MNNG) than non-fermented inulin, and the efficiency of DNA repair after 120 min of incubation decreased by 71%, 50% and 70%, respectively. The different degrees of genotoxicity inhibition observed for the various combinations of bacteria and prebiotics suggest that this effect may be attributable to carbohydrate type, SCFA yield, and the ratio of the end-products of prebiotic fermentation. Copyright © 2015 Elsevier Inc. All rights reserved.

The Effects of a Low-Carbohydrate Diet on Appetite: A Randomized Controlled Trial

PubMed Central

Hu, T; Yao, L; Reynolds, K; Niu, T; Li, S; Whelton, P; He, J; Bazzano, L

2015-01-01

Background and aims The relationship between dietary macronutrient composition and appetite is controversial. We examined the effects of a yearlong low-carbohydrate diet compared to a low-fat diet on appetite-related hormones and self-reported change in appetite. Methods and results A total of 148 adults with a body mass index 30–45 kg/m2, who were free of diabetes, cardiovascular disease and chronic kidney disease at baseline were randomly assigned to either a low-carbohydrate diet (carbohydrate [excluding dietary fiber]<40 g/day; N=75) or a low-fat diet (<30% energy from fat, <7% from saturated fat; N=73). Participants in both groups attended individual and group dietary counseling sessions where they were provided the same behavioral curriculum and advised to maintain baseline levels of physical activity. Appetite and appetite-related hormones were measured at 0, 3, 6 and 12 months of intervention. At 12 months, mean changes (95% CI) in peptide YY were −34.8 pg/mL (−41.0 to −28.6) and in the low-carbohydrate group and −44.2 pg/mL (−50.4 to −38.0) in the low-fat group (net change: 9.4 pg/mL [0.6 to 18.2 pg/mL]; p=0.036). Approximately 99% of dietary effects on peptide YY are explained by differences in dietary macronutrient content. There was no difference in change in ghrelin or self-reported change in appetite between the groups. Conclusions A low-fat diet reduced peptide YY more than a low-carbohydrate diet. These findings suggest that satiety may be better preserved on a low-carbohydrate diet, as compared to a low fat diet. PMID:26803589

Prebiotic mechanisms, functions and application

USDA-ARS?s Scientific Manuscript database

In October 2012, a group of scientists met at the 10th Meeting of the International Scientific Association of Probiotics and Prebiotics (ISAPP) in Cork, Ireland to discuss issues surrounding prebiotics and their development. This article summarises outputs from the meeting. Various prebiotic defin...

A randomized controlled trial of low carbohydrate and low fat/high fiber diets for weight loss.

PubMed Central

Baron, J A; Schori, A; Crow, B; Carter, R; Mann, J I

1986-01-01

Among 135 overweight subjects, we conducted a three-month randomized controlled trial of two sets of dietary advice, each providing approximately 1,000 calories per day but differing in fiber, carbohydrate, and fat content. Information on weight and eating habits, as well as measures of lipoprotein and glucose metabolism were obtained at entry and one and three months later. We found that dieters given low carbohydrate/low fiber dietary advice tended to lose more weight than those given a higher carbohydrate/higher fiber regimen (5.0 vs 3.7 kg on average at three months). This pattern was particularly marked among women, and among participants who were under age 40 or of lower social class. There were no differences between the diet groups in the proportion complaining of hunger but, in general, members of the low carbohydrate group complained of more problems in dieting. There were only minor differences in the serum lipoprotein patterns during the diet period. In view of these results, we believe previous claims of the benefits of fiber for weight loss may have been overstated. PMID:3021006

IMMUNO-MODULATORY PROPERTIES OF PREBIOTICS EXTRACTED FROM vernonia amygdalina.

PubMed

Im, Ezeonu; Ae, Asuquo; Bn, Ukwah; Po, Ukoha

2016-01-01

Vernonia amygdalina , commonly called bitter-leaf, is widely consumed in many parts of Africa, and Nigeria, in particular. The leaf extract has been reported to have antimicrobial, anti-plasmodial, anti-helminthic, as well as prebiotic properties, but its immuno-modulatory effects have not been well-studied, neither have the prebiotics been identified. This study evaluated the immuno-modulatory properties of the aqueous leaf extract and identified the prebiotic components. The immuno-modulatory potential was evaluated by monitoring the effects of oral administration of the extract on immunological, haematological and lipid profiles of Rattus norvegicus , while the prebiotic components were identified by thin layer chromatography (TLC), following liquid-liquid fractionation of the extract. Consumption of the extract caused significant increases in CD4+-, white blood cell-, total lymphocyte- and high density lipid (HDL) counts; decreases in low density lipid (LDL) and triglycerides and no significant effect on haemoglobin (Hb) and packed cell volume (PCV) in the blood of test animals. The water-soluble fraction of the extract contained most of the phyto-constituents of the extract and Thin Layer Chromatographic analysis of the fraction revealed the presence of fructo-oligosaccharide and galacto-oligosaccharide prebiotics. The results from this study have shown that the aqueous leaf extract of V. amygdalina has positive immune-modulatory and haematologic effects and contains some important prebiotic compounds.

Prebiotics in infant formula

PubMed Central

Vandenplas, Yvan; Greef, Elisabeth De; Veereman, Gigi

2014-01-01

The gastrointestinal microbiota of breast-fed babies differ from classic standard formula fed infants. While mother's milk is rich in prebiotic oligosaccharides and contains small amounts of probiotics, standard infant formula doesn’t. Different prebiotic oligosaccharides are added to infant formula: galacto-oligosaccharides, fructo-oligosaccharide, polydextrose, and mixtures of these. There is evidence that addition of prebiotics in infant formula alters the gastrointestinal (GI) microbiota resembling that of breastfed infants. They are added to infant formula because of their presence in breast milk. Infants on these supplemented formula have a lower stool pH, a better stool consistency and frequency and a higher concentration of bifidobacteria in their intestine compared to infants on a non-supplemented standard formula. Since most studies suggest a trend for beneficial clinical effects, and since these ingredients are very safe, prebiotics bring infant formula one step closer to breastmilk, the golden standard. However, despite the fact that adverse events are rare, the evidence on prebiotics of a significant health benefit throughout the alteration of the gut microbiota is limited. PMID:25535999

Prebiotics in infant formula.

PubMed

Vandenplas, Yvan; De Greef, Elisabeth; Veereman, Gigi

2014-01-01

The gastrointestinal microbiota of breast-fed babies differ from classic standard formula fed infants. While mother's milk is rich in prebiotic oligosaccharides and contains small amounts of probiotics, standard infant formula doesn't. Different prebiotic oligosaccharides are added to infant formula: galacto-oligosaccharides, fructo-oligosaccharide, polydextrose, and mixtures of these. There is evidence that addition of prebiotics in infant formula alters the gastrointestinal (GI) microbiota resembling that of breastfed infants. They are added to infant formula because of their presence in breast milk. Infants on these supplemented formula have a lower stool pH, a better stool consistency and frequency and a higher concentration of bifidobacteria in their intestine compared to infants on a non-supplemented standard formula. Since most studies suggest a trend for beneficial clinical effects, and since these ingredients are very safe, prebiotics bring infant formula one step closer to breastmilk, the golden standard. However, despite the fact that adverse events are rare, the evidence on prebiotics of a significant health benefit throughout the alteration of the gut microbiota is limited.

Effects of Low-Carbohydrate Diets Versus Low-Fat Diets on Metabolic Risk Factors: A Meta-Analysis of Randomized Controlled Clinical Trials

PubMed Central

Hu, Tian; Mills, Katherine T.; Yao, Lu; Demanelis, Kathryn; Eloustaz, Mohamed; Yancy, William S.; Kelly, Tanika N.; He, Jiang; Bazzano, Lydia A.

2012-01-01

The effects of low-carbohydrate diets (≤45% of energy from carbohydrates) versus low-fat diets (≤30% of energy from fat) on metabolic risk factors were compared in a meta-analysis of randomized controlled trials. Twenty-three trials from multiple countries with a total of 2,788 participants met the predetermined eligibility criteria (from January 1, 1966 to June 20, 2011) and were included in the analyses. Data abstraction was conducted in duplicate by independent investigators. Both low-carbohydrate and low-fat diets lowered weight and improved metabolic risk factors. Compared with participants on low-fat diets, persons on low-carbohydrate diets experienced a slightly but statistically significantly lower reduction in total cholesterol (2.7 mg/dL; 95% confidence interval: 0.8, 4.6), and low density lipoprotein cholesterol (3.7 mg/dL; 95% confidence interval: 1.0, 6.4), but a greater increase in high density lipoprotein cholesterol (3.3 mg/dL; 95% confidence interval: 1.9, 4.7) and a greater decrease in triglycerides (−14.0 mg/dL; 95% confidence interval: −19.4, −8.7). Reductions in body weight, waist circumference and other metabolic risk factors were not significantly different between the 2 diets. These findings suggest that low-carbohydrate diets are at least as effective as low-fat diets at reducing weight and improving metabolic risk factors. Low-carbohydrate diets could be recommended to obese persons with abnormal metabolic risk factors for the purpose of weight loss. Studies demonstrating long-term effects of low-carbohydrate diets on cardiovascular events were warranted. PMID:23035144

Motivating Low Performing Adolescent Readers. ERIC Digest.

ERIC Educational Resources Information Center

Collins, Norma Decker

This Digest focuses on motivating the low performing adolescent in a remedial reading or subject area classroom--the idea is that students who are disengaged from their own learning processes are not likely to perform well in school. The Digest points out that such adolescents are often caught in a cycle of failure and that secondary teachers must…

Complex carbohydrates in the dietary management of patients with glycogenosis caused by glucose-6-phosphatase deficiency.

PubMed

Smit, G P; Ververs, M T; Belderok, B; Van Rijn, M; Berger, R; Fernandes, J

1988-07-01

Carbohydrates with digestion characteristics between those of lente uncooked starches and rapidly digestible oligosaccharides were administered in a dose of 1.5 g/kg body weight to five patients with glycogenosis from glucose-6-phosphatase deficiency. Postprandial duration of normoglycemia and concentrations of blood insulin and lactate were determined. Uncooked barley groats in water, or incorporated in a meal turned out to behave as lente carbohydrates. Uncooked couscous in water, couscous incorporated in a meal, and partially cooked macaroni given as a meal behaved as semilente carbohydrates as compared with uncooked cornstarch and glucose. The in vitro determination of the digestibility index along with the in vivo tolerance test enables us to choose and incorporate semilente carbohydrates in the day-time treatment of patients.

Dietary carbohydrates and glucose metabolism in diabetic patients.

PubMed

Parillo, M; Riccardi, G

1995-12-01

Dietary carbohydrates represent one of the major sources of energy for the human body. However, the main (if not the only) therapy for diabetes since ancient times has been based on reducing dietary carbohydrates drastically because of their effects on blood glucose levels. The introduction of insulin in the 1920s and then of oral hypoglycaemic drugs led to various studies evaluating the biochemical characteristics of carbohydrates and their effects on glucose metabolism in diabetic patients. This review considers the role of dietary carbohydrates in the diet of diabetic patients in the light of the most recent studies and provides a short summary of the biochemistry of carbohydrates and the physiology of carbohydrate digestion.

Effects of a low-fat versus a low-carbohydrate diet on adipocytokines in obese adults.

PubMed

de Luis, D A; Aller, R; Izaola, O; Gonzalez Sagrado, M; Bellioo, D; Conde, R

2007-01-01

There are few studies addressing the effect of weight loss on circulating levels of adipocytokines. The aim of our study was to determine whether different diets would have different weight loss effects and to examine the changes in adipocytokine levels. A population of 90 obesity non-diabetic outpatients was analyzed in a prospective way. The patients were randomly allocated to two groups: (a) diet I (low-fat diet), and (b) diet II (low-carbohydrate diet). At baseline and after 3 months on the diet, adipocytokines were evaluated. 43 patients were randomized to group I and 47 patients to diet group II. No differences were detected between weight loss in either group (3.3 +/- 0.51 vs. 4.4 +/- 0.6 kg; n.s.). In group I, a significant decrease in leptin levels was found. In group II, leptin and C-reactive protein (CRP) levels also decreased. The decrease in leptin levels was lower with diet I than II (16.4 vs. 22.8%; p < 0.05). The serum leptin concentration decreased due to the 3-month intervention with low-fat and low-carbohydrate diets, without changes in other adipocytokines. The decrease in leptin and CRP levels were higher with a low-carbohydrate diet than a low-fat diet. Copyright 2007 S. Karger AG, Basel.

[Probiotics and prebiotics as a bioactive component of functional food].

PubMed

Kapka-Skrzypczak, Lucyna; Niedźwiecka, Joanna; Wojtyła, Andrzej; Kruszewski, Marcin

2012-01-01

The results of food science investigations have confirmed the relationship between the type of eaten food and health. Simultaneously, consumers are paying more and more attention to the kind of food they eat, as their awareness concerning the influence of proper food on health is increasing. On that base the conception of functional food has been created. This kind of food, besides being a source of essential macro- and micronutrients, exerts an additional positive influence on health. Probiotics and prebiotics containing products are a good example of functional food. These products provide not only essential nutrients but also microorganisms and polysaccharides, which are indigestible in the human alimentary tract, but exert a positive effect on human health. It may be a therapeutic or prophylactic effect due to specific affliction or may improve health in general. The paper - based on available literature - shows a positive influence of probiotics and prebiotics on human health, especially in the immunomodulation effect, an advantageous effect on the digestive system, antitumor activity and a possible therapeutic and prophylactic effect on cardiovascular diseases and obesity.

Low carbohydrate diets may increase risk of neural tube defects.

PubMed

Desrosiers, Tania A; Siega-Riz, Anna Maria; Mosley, Bridget S; Meyer, Robert E

2018-01-25

Folic acid fortification significantly reduced the prevalence of neural tube defects (NTDs) in the United States. The popularity of "low carb" diets raises concern that women who intentionally avoid carbohydrates, thereby consuming fewer fortified foods, may not have adequate dietary intake of folic acid. To assess the association between carbohydrate intake and NTDs, we analyzed data from the National Birth Defects Prevention Study from 1,740 mothers of infants, stillbirths, and terminations with anencephaly or spina bifida (cases), and 9,545 mothers of live born infants without a birth defect (controls) conceived between 1998 and 2011. Carbohydrate and folic acid intake before conception were estimated from food frequency questionnaire responses. Restricted carbohydrate intake was defined as ≤5th percentile among controls. Odds ratios were estimated with logistic regression and adjusted for maternal race/ethnicity, education, alcohol use, folic acid supplement use, study center, and caloric intake. Mean dietary intake of folic acid among women with restricted carbohydrate intake was less than half that of other women (p < .01), and women with restricted carbohydrate intake were slightly more likely to have an infant with an NTD (AOR = 1.30, 95% CI: 1.02, 1.67). This is the first study to examine the association between carbohydrate intake and NTDs among pregnancies conceived postfortification. We found that women with restricted carbohydrate intake were 30% more likely to have an infant with anencephaly or spina bifida. However, more research is needed to understand the pathways by which restricted carbohydrate intake might increase the risk of NTDs. © 2018 Wiley Periodicals, Inc.

Theoretical investigation of low detection sensitivity for underivatized carbohydrates in ESI and MALDI.

PubMed

Chen, Jien-Lian; Lee, Chuping; Lu, I-Chung; Chien, Chia-Lung; Lee, Yuan-Tseh; Hu, Wei-Ping; Ni, Chi-Kung

2016-12-01

Electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) mainly generate protonated ions from peptides and proteins but sodiated (or potassiated) ions from carbohydrates. The ion intensities of sodiated (or potassiated) carbohydrates generated by ESI and MALDI are generally lower than those of protonated peptides and proteins. Ab initio calculations and transition state theory were used to investigate the reasons for the low detection sensitivity for underivatized carbohydrates. We used glucose and cellobiose as examples and showed that the low detection sensitivity is partly attributable to the following factors. First, glucose exhibits a low proton affinity. Most protons generated by ESI or MALDI attach to water clusters and matrix molecules. Second, protonated glucose and cellobiose can easily undergo dehydration reactions. Third, the sodiation affinities of glucose and cellobiose are small. Some sodiated glucose and cellobiose dissociate into the sodium cations and neutral carbohydrates during ESI or MALDI process. The increase of detection sensitivity of carbohydrates in mass spectrometry by various methods can be rationalized according to these factors. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Detection of Inulin, a Prebiotic Polysaccharide, in Maple Syrup.

PubMed

Sun, Jiadong; Ma, Hang; Seeram, Navindra P; Rowley, David C

2016-09-28

Maple syrup is a widely consumed plant-derived natural sweetener produced by concentrating xylem sap collected from certain maple (Acer) species. During thermal evaporation of water, natural phytochemical components are concentrated in maple syrup. The polymeric components from maple syrup were isolated by ethanol precipitation, dialysis, and anion exchange chromatography and structurally characterized by glycosyl composition analysis, glycosyl linkage analysis, and nuclear magnetic resonance spectroscopy. Among the maple syrup polysaccharides, one neutral polysaccharide was characterized as inulin with a broad molecular weight distribution, representing the first isolation of this prebiotic carbohydrate from a xylem sap. In addition, two acidic polysaccharides with structural similarity were identified as arabinogalactans derived from rhamnogalacturonan type I pectic polysaccharides.

Postprandial Glucose Surges after Extremely Low Carbohydrate Diet in Healthy Adults.

PubMed

Kanamori, Koji; Ihana-Sugiyama, Noriko; Yamamoto-Honda, Ritsuko; Nakamura, Tomoka; Sobe, Chie; Kamiya, Shigemi; Kishimoto, Miyako; Kajio, Hiroshi; Kawano, Kimiko; Noda, Mitsuhiko

2017-09-01

Carbohydrate-restricted diets are prevalent not only in obese people but also in the general population to maintain appropriate body weight. Here, we report that extreme carbohydrate restriction for one day affects the subsequent blood glucose levels in healthy adults. Ten subjects (median age 30.5 years, BMI 21.1 kg/m 2 , and HbA1c 5.5%), wearing with a continuous glucose monitoring device, were given isoenergetic test meals for 4 consecutive days. On day 1, day 2 (D2), and day 4 (D4), they consumed normal-carbohydrate (63-66% carbohydrate) diet, while on day 3, they took low-carbohydrate/high-fat (5% carbohydrate) diet. The daily energy intake was 2,200 kcal for males and 1,700 kcal for females. On D2 and D4, we calculated the mean 24-hr blood glucose level (MEAN/24h) and its standard deviation (SD/24h), the area under the curve (AUC) for glucose over 140 mg/dL within 4 hours after each meal (AUC/4h/140), the mean amplitude of the glycemic excursions (MAGE), the incremental AUC of 24-hr blood glucose level above the mean plus one standard deviation (iAUC/MEAN+SD). Indexes for glucose fluctuation on D4 were significantly greater than those on D2 (SD/24h; p = 0.009, MAGE; p = 0.013, AUC/4h/140 after breakfast and dinner; p = 0.006 and 0.005, and iAUC/MEAN+SD; p = 0.007). The value of MEAN/24h and AUC/4h/140 after lunch on D4 were greater than those on D2, but those differences were not statistically significant. In conclusion, consumption of low-carbohydrate/high-fat diet appears to cause higher postprandial blood glucose on subsequent normal-carbohydrate diet particularly after breakfast and dinner in healthy adults.

Phytochemical Properties and Nutrigenomic Implications of Yacon as a Potential Source of Prebiotic: Current Evidence and Future Directions

PubMed Central

Cao, Yang; Zhang, Hongxia; Jin, Yifan; Zhang, Yihe; Hayford, Frank

2018-01-01

The human gut is densely populated with diverse microbial communities that are essential to health. Prebiotics and fiber have been shown to possess the ability to modulate the gut microbiota. One of the plants being considered as a potential source of prebiotic is yacon. Yacon is an underutilized plant consumed as a traditional root-based fruit in South America. Yacon mainly contains fructooligosaccharides (FOS) and inulin. Therefore, it has bifidogenic benefits for gut health, because FOS are not easily broken down by digestive enzymes. Bioactive chemical compounds and extracts isolated from yacon have been studied for their various nutrigenomic properties, including as a prebiotic for intestinal health and their antimicrobial and antioxidant effects. This article reviewed scientific studies regarding the bioactive chemical compounds and nutrigenomic properties of extracts and isolated compounds from yacon. These findings may help in further research to investigate yacon-based nutritional products. Yacon can be considered a potential prebiotic source and a novel functional food. However, more detailed epidemiological, animal, and human clinical studies, particularly mechanism-based and phytopharmacological studies, are lacking for the development of evidence-based functional food products. PMID:29649123

Phytochemical Properties and Nutrigenomic Implications of Yacon as a Potential Source of Prebiotic: Current Evidence and Future Directions.

PubMed

Cao, Yang; Ma, Zheng Feei; Zhang, Hongxia; Jin, Yifan; Zhang, Yihe; Hayford, Frank

2018-04-12

The human gut is densely populated with diverse microbial communities that are essential to health. Prebiotics and fiber have been shown to possess the ability to modulate the gut microbiota. One of the plants being considered as a potential source of prebiotic is yacon. Yacon is an underutilized plant consumed as a traditional root-based fruit in South America. Yacon mainly contains fructooligosaccharides (FOS) and inulin. Therefore, it has bifidogenic benefits for gut health, because FOS are not easily broken down by digestive enzymes. Bioactive chemical compounds and extracts isolated from yacon have been studied for their various nutrigenomic properties, including as a prebiotic for intestinal health and their antimicrobial and antioxidant effects. This article reviewed scientific studies regarding the bioactive chemical compounds and nutrigenomic properties of extracts and isolated compounds from yacon. These findings may help in further research to investigate yacon-based nutritional products. Yacon can be considered a potential prebiotic source and a novel functional food. However, more detailed epidemiological, animal, and human clinical studies, particularly mechanism-based and phytopharmacological studies, are lacking for the development of evidence-based functional food products.

Prebiotic chemistry: chemical evolution of organics on the primitive Earth under simulated prebiotic conditions.

PubMed

Dondi, Daniele; Merli, Daniele; Pretali, Luca; Fagnoni, Maurizio; Albini, Angelo; Serpone, Nick

2007-11-01

A series of prebiotic mixtures of simple molecules, sources of C, H, N, and O, were examined under conditions that may have prevailed during the Hadean eon (4.6-3.8 billion years), namely an oxygen-free atmosphere and a significant UV radiation flux over a large wavelength range due to the absence of an ozone layer. Mixtures contained a C source (methanol, acetone or other ketones), a N source (ammonia or methylamine), and an O source (water) at various molar ratios of C : H : N : O. When subjected to UV light or heated for periods of 7 to 45 days under an argon atmosphere, they yielded a narrow product distribution of a few principal compounds. Different initial conditions produced different distributions. The nature of the products was ascertained by gas chromatographic-mass spectral analysis (GC-MS). UVC irradiation of an aqueous methanol-ammonia-water prebiotic mixture for 14 days under low UV dose (6 x 10(-2) Einstein) produced methylisourea, hexamethylenetetramine (HMT), methyl-HMT and hydroxy-HMT, whereas under high UV dose (45 days; 1.9 x 10(-1) Einstein) yielded only HMT. By contrast, the prebiotic mixture composed of acetone-ammonia-water produced five principal species with acetamide as the major component; thermally the same mixture produced a different product distribution of four principal species. UVC irradiation of the CH(3)CN-NH(3)-H(2)O prebiotic mixture for 7 days gave mostly trimethyl-s-triazine, whereas in the presence of two metal oxides (TiO(2) or Fe(2)O(3)) also produced some HMT; the thermal process yielded only acetamide.

Low-fat versus low-carbohydrate weight reduction diets: effects on weight loss, insulin resistance, and cardiovascular risk: a randomized control trial.

PubMed

Bradley, Una; Spence, Michelle; Courtney, C Hamish; McKinley, Michelle C; Ennis, Cieran N; McCance, David R; McEneny, Jane; Bell, Patrick M; Young, Ian S; Hunter, Steven J

2009-12-01

Low-fat hypocaloric diets reduce insulin resistance and prevent type 2 diabetes in those at risk. Low-carbohydrate, high-fat diets are advocated as an alternative, but reciprocal increases in dietary fat may have detrimental effects on insulin resistance and offset the benefits of weight reduction. We investigated a low-fat (20% fat, 60% carbohydrate) versus a low-carbohydrate (60% fat, 20% carbohydrate) weight reduction diet in 24 overweight/obese subjects ([mean +/- SD] BMI 33.6 +/- 3.7 kg/m(2), aged 39 +/- 10 years) in an 8-week randomized controlled trial. All food was weighed and distributed, and intake was calculated to produce a 500 kcal/day energy deficit. Insulin action was assessed by the euglycemic clamp and insulin secretion by meal tolerance test. Body composition, adipokine levels, and vascular compliance by pulse-wave analysis were also measured. Significant weight loss occurred in both groups (P < 0.01), with no difference between groups (P = 0.40). Peripheral glucose uptake increased, but there was no difference between groups (P = 0.28), and suppression of endogenous glucose production was also similar between groups. Meal tolerance-related insulin secretion decreased with weight loss with no difference between groups (P = 0.71). The change in overall systemic arterial stiffness was, however, significantly different between diets (P = 0.04); this reflected a significant decrease in augmentation index following the low-fat diet, compared with a nonsignificant increase within the low-carbohydrate group. This study demonstrates comparable effects on insulin resistance of low-fat and low-carbohydrate diets independent of macronutrient content. The difference in augmentation index may imply a negative effect of low-carbohydrate diets on vascular risk.

Effect of acarbose on postprandial blood glucose concentrations in healthy cats fed low and high carbohydrate diets.

PubMed

Singh, Ranee; Rand, Jacquie S; Coradini, Marcia; Morton, John M

2015-10-01

Feeding a low carbohydrate diet is recommended for diabetic cats; however, some cats may require diets containing moderate-to-high carbohydrate and may benefit from the use of therapeutic agents to improve glycemic control. The aim of the study was to determine the effect of the α-glucosidase inhibitor acarbose on postprandial plasma glucose concentration when combined with commercially available feline diets high and low in carbohydrate. Twelve healthy, adult, non-obese, neutered cats were enrolled. Plasma glucose concentrations were assessed over 24 h after feeding high and low carbohydrate diets, with and without acarbose, during single and multiple meal tests, in a crossover study. Commercially available feline diets were used, which were high and low in carbohydrate (providing 51% and 7% of metabolizable energy, respectively). In cats fed the high carbohydrate diet as a single meal, mean 24 h glucose concentrations were lower when acarbose was administered. Mean glucose concentrations were lower in the first 12 h when acarbose was given once daily, whereas no significant difference was observed in mean results from 12-24 h. Acarbose had little effect in cats eating multiple meals. Compared with consumption of the high carbohydrate diet with acarbose, lower mean 24 h and peak glucose concentrations were achieved by feeding the low carbohydrate diet alone. In healthy cats meal-fed diets of similar composition to the diets used in this study, acarbose has minimal effect when a low carbohydrate diet is fed but reduces postprandial glucose concentrations over 24 h when a high carbohydrate diet is fed. However, mean glucose concentrations over 24 h are still higher when a high carbohydrate diet with acarbose is fed relative to the low carbohydrate diet without acarbose. Future studies in diabetic cats are warranted to confirm these findings. © ISFM and AAFP 2014.

Prebiotic Potential of Herbal Medicines Used in Digestive Health and Disease.

PubMed

Peterson, Christine Tara; Sharma, Vandana; Uchitel, Sasha; Denniston, Kate; Chopra, Deepak; Mills, Paul J; Peterson, Scott N

2018-03-22

The prebiotic potential of herbal medicines has been scarcely studied. The authors therefore used anaerobic human fecal cultivation to investigate whether three herbal medicines commonly used in gastrointestinal health and disease in Ayurveda alter the growth and abundance of specific bacterial species. Profiling of cultures supplemented with Glycyrrhiza glabra, Ulmus rubra, or triphala formulation by 16S rDNA sequencing revealed profound changes in diverse taxa in human gut microbiota. Principal coordinate analysis highlights that each herbal medicine drives the formation of unique microbial communities. The relative abundance of approximately one-third of the 299 species profiled was altered by all 3 medicines, whereas additional species displayed herb-specific alterations. Herb supplementation increased the abundance of many bacteria known to promote human health, including Bifidobacterium spp., Lactobacillus spp., and Bacteroides spp. Herb supplementation resulted in the reduced relative abundance of many species, including potential pathogens such as Citrobacter freundii and Klebsiella pneumoniae. Herbal medicines induced blooms of butyrate- and propionate-producing species. U. rubra and triphala significantly increased the relative abundance of butyrate-producing bacteria, whereas G. glabra induced the largest increase in propionate-producing species. To achieve greater insight into the mechanisms through which herbal medicines alter microbial communities, the authors assessed the shifts in abundance of glycosyl hydrolase families induced by each herbal medicine. Herb supplementation, particularly G. glabra, significantly increased the representation and potential expression of several glycosyl hydrolase families. These studies are novel in highlighting the significant prebiotic potential of medicinal herbs and suggest that the health benefits of these herbs are due, at least in part, to their ability to modulate the gut microbiota in a manner predicted to

Factors associated with choice of a low-fat or low-carbohydrate diet during a behavioral weight loss intervention.

PubMed

McVay, Megan A; Voils, Corrine I; Coffman, Cynthia J; Geiselman, Paula J; Kolotkin, Ronette L; Mayer, Stephanie B; Smith, Valerie A; Gaillard, Leslie; Turner, Marsha J; Yancy, William S

2014-12-01

Individuals undertaking a weight loss effort have a choice among proven dietary approaches. Factors contributing to choice of either a low-fat/low-calorie diet or a low-carbohydrate diet, two of the most studied and popular dietary approaches, are unknown. The current study used data from participants randomized to the 'choice' arm of a trial examining whether being able to choose a diet regimen yields higher weight loss than being randomly assigned to a diet. At study entry, participants attended a group session during which they were provided tailored feedback indicating which diet was most consistent with their food preferences using the Geiselman Food Preference Questionnaire (FPQ), information about both diets, and example meals for each diet. One week later, they indicated which diet they chose to follow during the 48-week study, with the option of switching diets after 12 weeks. Of 105 choice arm participants, 44 (42%) chose the low-fat/low-calorie diet and 61 (58%) chose the low-carbohydrate diet. In bivariate analyses, diet choice was not associated with age, race, sex, education, BMI, or diabetes (all p > 0.05). Low-carbohydrate diet choice was associated with baseline higher percent fat intake (p = 0.007), lower percent carbohydrate intake (p = 0.02), and food preferences consistent with a low-carbohydrate diet according to FPQ (p < 0.0001). In a multivariable logistic regression model, only FPQ diet preference was associated with diet choice (p = 0.001). Reported reasons for diet choice were generally similar for those choosing either diet; however, concerns about negative health effects of the unselected diet was rated as more influential among participants selecting the low-fat diet. Only three low-carbohydrate and two low-fat diet participants switched diets at 12 weeks. Results suggest that when provided a choice between two popular weight loss dietary approaches, an individual's selection is likely influenced by baseline dietary

Quantitative analysis of total proteins and carbohydrates in the digestive gland-gonad complex (DGG) and hemolymph of the freshwater prosobranch snail Lanistes carinatus.

PubMed

Hassan, Amaal Hassan M; Mahmoud, Salim; El-Hamidy, A

2010-08-01

Laboratory investigations were carried out to quantify the amount of total proteins, carbohydrates and reducing sugar in the hemolymph and Digestive Gland Gonad- complex (DGG) of infected and uinfected lanistes arinatus. Snails were naturally infected with two different types of trematode la:val stages (rediae of gymnocepahalus cercaria and sporocyst of xiphidiocercaria), collected from the River Nile at Sohag governorate, Egypt. Analysis was carried out using an extraction of the DGGs tissue with buffer solution, while snails' hemolymph was applied directly. The results revealed that snail infection by rediae of gymnocephalus cercariae led to non significant increasing in both total carbohydrates and protein in hemolymph. However, infection by sporocysts of xiphidiocercariae caused a significant increasing only in hemolymph total protein. On the other hand, the amount of both reducing sugar and total proteins in DGG did not increase significantly whenever the infection caused by both types of trematode larvae. However, total carbohydrates in DGG increased significantly.

Prepregnancy low-carbohydrate dietary pattern and risk of gestational diabetes mellitus: a prospective cohort study1234

PubMed Central

Bao, Wei; Bowers, Katherine; Tobias, Deirdre K; Olsen, Sjurdur F; Chavarro, Jorge; Vaag, Allan; Kiely, Michele; Zhang, Cuilin

2014-01-01

Background: Low-carbohydrate diets (LCDs) have been vastly popular for weight loss. The association between a low-carbohydrate dietary pattern and risk of gestational diabetes mellitus (GDM) remains unknown. Objective: We aimed to prospectively examine the association of 3 prepregnancy low-carbohydrate dietary patterns with risk of GDM. Design: We included 21,411 singleton pregnancies in the Nurses’ Health Study II. Prepregnancy LCD scores were calculated from validated food-frequency questionnaires, including an overall LCD score on the basis of intakes of carbohydrate, total protein, and total fat; an animal LCD score on the basis of intakes of carbohydrate, animal protein, and animal fat; and a vegetable LCD score on the basis of intakes of carbohydrate, vegetable protein, and vegetable fat. A higher score reflected a higher intake of fat and protein and a lower intake of carbohydrate, and it indicated closer adherence to a low-carbohydrate dietary pattern. RRs and 95% CIs were estimated by using generalized estimating equations with log-binomial models. Results: We documented 867 incident GDM pregnancies during 10 y follow-up. Multivariable-adjusted RRs (95% CIs) of GDM for comparisons of highest with lowest quartiles were 1.27 (1.06, 1.51) for the overall LCD score (P-trend = 0.03), 1.36 (1.13, 1.64) for the animal LCD score (P-trend = 0.003), and 0.84 (0.69, 1.03) for the vegetable LCD score (P-trend = 0.08). Associations between LCD scores and GDM risk were not significantly modified by age, parity, family history of diabetes, physical activity, or overweight status. Conclusions: A prepregnancy low-carbohydrate dietary pattern with high protein and fat from animal-food sources is positively associated with GDM risk, whereas a prepregnancy low-carbohydrate dietary pattern with high protein and fat from vegetable food sources is not associated with the risk. Women of reproductive age who follow a low-carbohydrate dietary pattern may consider consuming

Prebiotics and Inflammatory Bowel Disease.

PubMed

Rasmussen, Heather E; Hamaker, Bruce R

2017-12-01

Dietary fiber, specifically prebiotics, is the primary source of energy for the gut microbiota and thus has the potential to beneficially modify microbiota composition. Prebiotics have been used in both in vitro studies and with animal models of colitis with largely positive results. Human studies are few and have been conducted with only a few select prebiotics, primarily fructan-containing fibers. Although disease activity and inflammatory markers have improved, more needs to be learned about the specific prebiotic compounds and how they can be used to best improve the gut microbiota to counter changes induced by inflammatory bowel disease. Copyright © 2017 Elsevier Inc. All rights reserved.

Carbohydrate-active enzymes from the zygomycete fungus Rhizopus oryzae: a highly specialized approach to carbohydrate degradation depicted at genome level

PubMed Central

2011-01-01

Background Rhizopus oryzae is a zygomycete filamentous fungus, well-known as a saprobe ubiquitous in soil and as a pathogenic/spoilage fungus, causing Rhizopus rot and mucomycoses. Results Carbohydrate Active enzyme (CAZy) annotation of the R. oryzae identified, in contrast to other filamentous fungi, a low number of glycoside hydrolases (GHs) and a high number of glycosyl transferases (GTs) and carbohydrate esterases (CEs). A detailed analysis of CAZy families, supported by growth data, demonstrates highly specialized plant and fungal cell wall degrading abilities distinct from ascomycetes and basidiomycetes. The specific genomic and growth features for degradation of easily digestible plant cell wall mono- and polysaccharides (starch, galactomannan, unbranched pectin, hexose sugars), chitin, chitosan, β-1,3-glucan and fungal cell wall fractions suggest specific adaptations of R. oryzae to its environment. Conclusions CAZy analyses of the genome of the zygomycete fungus R. oryzae and comparison to ascomycetes and basidiomycete species revealed how evolution has shaped its genetic content with respect to carbohydrate degradation, after divergence from the Ascomycota and Basidiomycota. PMID:21241472

Influence of dietary supplementation of prebiotics (mannanoligosaccharide) on the performance of crossbred calves.

PubMed

Ghosh, Sudipta; Mehla, Ram Kumar

2012-03-01

Thirty-six Holstein cross calves 5 days of age in their preruminant stage were used to study the effect of feeding prebiotic (mannanoligosaccharide) on their performance up to the age of 2 months. Treatment and control groups consisted of 18 calves each. Treatment group was supplemented with 4 g prebiotic (mannanoligosaccharide)/calf/day. Performance was evaluated by measuring average body weight (BW) gain, feed intake [dry matter (DM), total digestible nutrient (TDN) and crude protein(CP)], feed conversion efficiency (DM, TDN, and CP), fecal score, fecal coliform count and feeding cost. Body weight measured weekly, feed intake measured twice daily, proximate analysis of feeds and fodders analyzed weekly, fecal score monitored daily and fecal coliform count done weekly. There was a significant increase in average body weight gain, feed intake and feed conversion efficiency; and a significant decrease in severity of scours as measured by fecal score and fecal coliform count in the treatment group compared with control group (P < 0.01). Feed cost/kg BW gain was significantly lower in the treatment group compared to control group (P < 0.01). The results suggest that prebiotic (mannanoligosaccharide) can be supplemented to the calves for better performance.

Carbohydrate maldigestion induces necrotizing enterocolitis in preterm pigs

PubMed Central

Thymann, Thomas; Møller, Hanne K.; Stoll, Barbara; Støy, Ann Cathrine F.; Buddington, Randal K.; Bering, Stine B.; Jensen, Bent B.; Olutoye, Oluyinka O.; Siggers, Richard H.; Mølbak, Lars; Sangild, Per T.

2009-01-01

Necrotizing enterocolitis (NEC) remains the most severe gastrointestinal disorder in preterm infants. It is associated with the initiation of enteral nutrition and may be related to immature carbohydrate digestive capacity. We tested the hypothesis that a formula containing maltodextrin vs. a formula containing lactose as the principal source of carbohydrate would predispose preterm pigs to a higher NEC incidence. Cesarean-derived preterm pigs were given total parenteral nutrition for 48 h followed by total enteral nutrition with a lactose-based (n = 11) or maltodextrin-based (n = 11) formula for 36 h. A higher incidence (91% vs. 27%) and severity (score of 3.3 vs. 1.8) of NEC were observed in the maltodextrin than in the lactose group. This higher incidence of NEC in the maltodextrin group was associated with significantly lower activities of lactase, maltase, and aminopeptidase; reduced villus height; transiently reduced in vivo aldohexose uptake; and reduced ex vivo aldohexose uptake capacity in the middle region of the small intestine. Bacterial diversity was low for both diets, but alterations in bacterial composition and luminal concentrations of short-chain fatty acids were observed in the maltodextrin group. In a second study, we quantified net portal absorption of aldohexoses (glucose and galactose) during acute jejunal infusion of a maltodextrin- or a lactose-based formula (n = 8) into preterm pigs. We found lower net portal aldohexose absorption (4% vs. 42%) and greater intestinal recovery of undigested carbohydrate (68% vs. 27%) in pigs acutely perfused with the maltodextrin-based formula than those perfused with the lactose-based formula. The higher digestibility of the lactose than the maltodextrin in the formulas can be attributed to a 5- to 20-fold higher hydrolytic activity of tissue-specific lactase than maltases. We conclude that carbohydrate maldigestion is sufficient to increase the incidence and severity of NEC in preterm pigs. PMID:19808655

Non-digestible oligosaccharides directly regulate host kinome to modulate host inflammatory responses without alterations in the gut microbiota.

PubMed

Wu, Richard Y; Määttänen, Pekka; Napper, Scott; Scruten, Erin; Li, Bo; Koike, Yuhki; Johnson-Henry, Kathene C; Pierro, Agostino; Rossi, Laura; Botts, Steven R; Surette, Michael G; Sherman, Philip M

2017-10-10

Prebiotics are non-digestible food ingredients that enhance the growth of certain microbes within the gut microbiota. Prebiotic consumption generates immune-modulatory effects that are traditionally thought to reflect microbial interactions within the gut. However, recent evidence suggests they may also impart direct microbe-independent effects on the host, though the mechanisms of which are currently unclear. Kinome arrays were used to profile the host intestinal signaling responses to prebiotic exposures in the absence of microbes. Identified pathways were functionally validated in Caco-2Bbe1 intestinal cell line and in vivo model of murine endotoxemia. We found that prebiotics directly regulate host mucosal signaling to alter response to bacterial infection. Intestinal epithelial cells (IECs) exposed to prebiotics are hyporesponsive to pathogen-induced mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) activations, and have a kinome profile distinct from non-treated cells pertaining to multiple innate immune signaling pathways. Consistent with this finding, mice orally gavaged with prebiotics showed dampened inflammatory response to lipopolysaccharide (LPS) without alterations in the gut microbiota. These findings provide molecular mechanisms of direct host-prebiotic interactions to support prebiotics as potent modulators of host inflammation.

Electron-induced origins of prebiotic building blocks of sugars: mechanism of self-reactions of a methanol anion dimer

NASA Astrophysics Data System (ADS)

Karsili, Tolga N. V.; Fennimore, Mark A.; Matsika, Spiridoula

The elementary synthesis of prebiotic molecules has attracted vast attention in recent years. Due to their rich surface chemistry and lack of suitable atmosphere, comets represent an important host for such synthesis, especially since they are routinely irradiated with short wavelength electromagnetic radiation and energetic cosmological electrons. Using high-level electronic structure theory, we present the details of the reactivity associated with the electron-impact induced prebiotic synthesis of ethylene glycol (a carbohydrate building block) from elementary methanol. The results suggest that the experimentally observed intermediates and fragment products can be viably formed by both neutral excited-state chemistry and by dissociative electron attachment - highlighting the importance of a theoretical mapping of the relevant potential energy surfaces that ultimately act as an important guide to the experimental results.

Prebiotics: application in bakery and pasta products.

PubMed

Padma Ishwarya, S; Prabhasankar, P

2014-01-01

The concept of functional foods has markedly moved toward gastrointestinal health. The prebiotic approach aims at achieving favorable milieu in the human gut by stimulating beneficial bacteria. Several food products act as substrates for the application of prebiotic substances and bakery products are one such category. The trend of increasing consumption of bakery products justifies the choice of using them as vehicles for delivering the prebiotic compounds. Apart from the health benefits, the prebiotic compounds also have nutritional and technological effects in the food matrix. In addition to increasing the fiber content, the candidate prebiotics also affect the rheology and final quality of bakery products. The prebiotic compounds are selected accordingly to confer desirable properties in the final product. The health advantages of prebiotics being well established, the technological advantages in bakery products such as bread and biscuits and extruded product such as pasta are discussed elaborately.

Dietary glucose stimulus at larval stage modifies the carbohydrate metabolic pathway in gilthead seabream (Sparus aurata) juveniles: An in vivo approach using (14)C-starch.

PubMed

Rocha, Filipa; Dias, Jorge; Geurden, Inge; Dinis, Maria Teresa; Panserat, Stephane; Engrola, Sofia

2016-11-01

The concept of nutritional programming was investigated in order to enhance the use of dietary carbohydrates in gilthead seabream juveniles. We assessed the long-term effects of high-glucose stimuli, exerted at the larval stage, on the growth performance, nutrient digestibility and metabolic utilization and gene expression of seabream juveniles, challenged with a high-carbohydrate intake. During early development, a group of larvae (control, CTRL) were kept under a rich-protein-lipid feeding regime whereas another group (GLU) was subjected to high-glucose stimuli, delivered intermittently over time. At juvenile stage, triplicate groups (IBW: 2.5g) from each fish nutritional background were fed a high-protein (59.4%) low-carbohydrate (2.0%) diet before being subjected to a low-protein (43.0%) high-carbohydrate (33.0%) dietary challenge for 36-days. Fish from both treatments increased by 8-fold their initial body weight, but neither growth rate, feed intake, feed and protein efficiency, nutrient retention (except lipids) nor whole-body composition were affected (P˃0.05) by fish early nutritional history. Nutrient digestibility was also similar among both groups. The metabolic fate of (14)C-starch and (14)C-amino acids tracers was estimated; GLU juveniles showed higher absorption of starch-derived glucose in the gut, suggesting an enhanced digestion of carbohydrates, while amino acid use was not affected. Moreover, glucose was less used for de novo synthesis of hepatic proteins and muscle glycogen from GLU fish (P<0.05). Our metabolic data suggests that the early glucose stimuli may alter carbohydrate utilization in seabream juveniles. Copyright © 2016 Elsevier Inc. All rights reserved.

High carbohydrate-low protein consumption maximizes Drosophila lifespan

PubMed Central

Bruce, Kimberley D.; Hoxha, Sany; Carvalho, Gil B.; Yamada, Ryuichi; Wang, Horng-Dar; Karayan, Paul; He, Shan; Brummel, Ted; Kapahi, Pankaj; Ja, William W.

2013-01-01

Dietary restriction extends lifespan in a variety of organisms, but the key nutritional components driving this process and how they interact remain uncertain. In Drosophila, while a substantial body of research suggests that protein is the major dietary component affecting longevity, recent studies claim that carbohydrates also play a central role. To clarify how nutritional factors influence longevity, nutrient consumption and lifespan were measured on a series of diets with varying yeast and sugar content. We show that optimal lifespan requires both high carbohydrate and low protein consumption, but neither nutrient by itself entirely predicts lifespan. Increased dietary carbohydrate or protein concentration does not always result in reduced feeding—the regulation of food consumption is best described by a constant daily caloric intake target. Moreover, due to differences in food intake, increased concentration of a nutrient within the diet does not necessarily result in increased consumption of that particular nutrient. Our results shed light on the issue of dietary effects on lifespan and highlight the need for accurate measures of nutrient intake in dietary manipulation studies. PMID:23403040

The role of energy expenditure in the differential weight loss in obese women on low-fat and low-carbohydrate diets.

PubMed

Brehm, Bonnie J; Spang, Suzanne E; Lattin, Barbara L; Seeley, Randy J; Daniels, Stephen R; D'Alessio, David A

2005-03-01

We have recently reported that obese women randomized to a low-carbohydrate diet lost more than twice as much weight as those following a low-fat diet over 6 months. The difference in weight loss was not explained by differences in energy intake because women on the two diets reported similar daily energy consumption. We hypothesized that chronic ingestion of a low-carbohydrate diet increases energy expenditure relative to a low-fat diet and that this accounts for the differential weight loss. To study this question, 50 healthy, moderately obese (body mass index, 33.2 +/- 0.28 kg/m(2)) women were randomized to 4 months of an ad libitum low-carbohydrate diet or an energy-restricted, low-fat diet. Resting energy expenditure (REE) was measured by indirect calorimetry at baseline, 2 months, and 4 months. Physical activity was estimated by pedometers. The thermic effect of food (TEF) in response to low-fat and low-carbohydrate breakfasts was assessed over 5 h in a subset of subjects. Forty women completed the trial. The low-carbohydrate group lost more weight (9.79 +/- 0.71 vs. 6.14 +/- 0.91 kg; P < 0.05) and more body fat (6.20 +/- 0.67 vs. 3.23 +/- 0.67 kg; P < 0.05) than the low-fat group. There were no differences in energy intake between the diet groups as reported on 3-d food records at the conclusion of the study (1422 +/- 73 vs. 1530 +/- 102 kcal; 5954 +/- 306 vs. 6406 +/- 427 kJ). Mean REE in the two groups was comparable at baseline, decreased with weight loss, and did not differ at 2 or 4 months. The low-fat meal caused a greater 5-h increase in TEF than did the low-carbohydrate meal (53 +/- 9 vs. 31 +/- 5 kcal; 222 +/- 38 vs. 130 +/- 21 kJ; P = 0.017). Estimates of physical activity were stable in the dieters during the study and did not differ between groups. These results confirm that short-term weight loss is greater in obese women on a low-carbohydrate diet than in those on a low-fat diet even when reported food intake is similar. The differential weight

Prebiotics in Companion and Livestock Animal Nutrition

NASA Astrophysics Data System (ADS)

Barry, Kathleen A.; Vester, Brittany M.; Fahey, George C.

Prebiotic supplementation of animal diets began in an attempt to increase concentrations of beneficial intestinal microbiota. It was understood that prebiotics inhibited growth of intestinal pathogens and decreased concentrations of stool odor-causing metabolites. Since the use of prebiotics began, several countries have banned the use of antimicrobials in livestock animal feeds, and several more have placed restrictions on the quantity of antimicrobials that can be used. Prebiotic supplementation has become increasingly popular as the body of evidence supporting its use continues to grow. As this literature expands, the number of potential prebiotic substances has grown beyond those that are naturally occurring, such as those found in chicory and yeast products, to include a large number of synthetic or chemically/enzymatically manufactured prebiotics.

Application of high rate, high temperature anaerobic digestion to fungal thermozyme hydrolysates from carbohydrate wastes.

PubMed

Forbes, C; O'Reilly, C; McLaughlin, L; Gilleran, G; Tuohy, M; Colleran, E

2009-05-01

The objective of this study was to examine the feasibility of using a two-step, fully biological and sustainable strategy for the treatment of carbohydrate rich wastes. The primary step in this strategy involves the application of thermostable enzymes produced by the thermophilic, aerobic fungus, Talaromyces emersonii, to carbohydrate wastes producing a liquid hydrolysate discharged at elevated temperatures. To assess the potential of thermophilic treatment of this hydrolysate, a comparative study of thermophilic and mesophilic digestion of four sugar rich thermozyme hydrolysate waste streams was conducted by operating two high rate upflow anaerobic hybrid reactors (UAHR) at 37 degrees C (R1) and 55 degrees C (R2). The operational performance of both reactors was monitored from start-up by assessing COD removal efficiencies, volatile fatty acid (VFA) discharge and % methane of the biogas produced. Rapid start-up of both R1 and R2 was achieved on an influent composed of the typical sugar components of the organic fraction of municipal solid waste (OFMSW). Both reactors were subsequently challenged in terms of volumetric loading rate (VLR) and it was found that a VLR of 9 gCOD l(-1)d(-1) at a hydraulic retention time (HRT) of 1 day severely affected the thermophilic reactor with instability characterised by a build up of volatile fatty acid (VFA) intermediates in the effluent. The influent to both reactors was changed to a simple glucose and sucrose-based influent supplied at a VLR of 4.5 gCOD l(-1)d(-1) and HRT of 2 days prior to the introduction of thermozyme hydrolysates. Four unique thermozyme hydrolysates were subsequently supplied to the reactors, each for a period of 10 HRTs. The applied hydrolysates were derived from apple pulp, bread, carob powder and cardboard, all of which were successfully and comparably converted by both reactors. The % total carbohydrate removal by both reactors was monitored during the application of the sugar rich thermozyme

Hepatic glucose metabolic responses to digestible dietary carbohydrates in two isogenic lines of rainbow trout.

PubMed

Song, Xuerong; Marandel, Lucie; Dupont-Nivet, Mathilde; Quillet, Edwige; Geurden, Inge; Panserat, Stephane

2018-06-05

Rainbow trout ( Oncorhynchus mykiss ) was recognized as a typical 'glucose-intolerant' fish and poor dietary carbohydrate user. Our first objective was to test the effect of dietary carbohydrates themselves (without modification of dietary protein intake) on hepatic glucose gene expression (taking into account the paralogs). The second aim was to research if two isogenic trout lines had different responses to carbohydrate intake, showing one with a better use dietary carbohydrates. Thus, we used two isogenic lines of rainbow trout (named A32h and AB1h) fed with either a high carbohydrate diet or a low carbohydrate diet for 12 weeks. We analysed the zootechnical parameters, the plasma metabolites, the hepatic glucose metabolism at the molecular level and the hormonal-nutrient sensing pathway. Globally, dietary carbohydrate intake was associated with hyperglycaemia and down regulation of the energy sensor Ampk, but also with atypical regulation of glycolysis and gluconeogenesis in the liver. Indeed, the first steps of glycolysis and gluconeogenesis catalysed by the glucokinase and the phospenolpyruvate carboxykinase are regulated at the molecular level by dietary carbohydrates as expected (i.e. induction of the glycolytic gck and repression of the gluconeogenic pck ); by contrast, and surprisingly, for two other key glycolytic enzymes (phosphofructokinase enzyme - pfk l and pyruvate kinase - p k ) some of the paralogs ( pfklb and pklr ) are inhibited by carbohydrates whereas some of the genes coding gluconeogenic enzymes (the glucose-6-phosphatase enzyme g6pcb1b and g6pcb2a gene and the fructose1-6 biphosphatase paralog fbp1a ) are induced. On the other hand, some differences for the zootechnical parameters and metabolic genes were also found between the two isogenic lines, confirming the existence of genetic polymorphisms for nutritional regulation of intermediary metabolism in rainbow trout. In conclusion, our study determines some new and unexpected molecular

(1)H NMR spectroscopy for profiling complex carbohydrate mixtures in non-fractionated beer.

PubMed

Petersen, Bent O; Nilsson, Mathias; Bøjstrup, Marie; Hindsgaul, Ole; Meier, Sebastian

2014-05-01

A plethora of biological and biotechnological processes involve the enzymatic remodelling of carbohydrates in complex mixtures whose compositions affect both the processes and products. In the current study, we employed high-resolution (1)H NMR spectroscopy for the analysis of cereal-derived carbohydrate mixtures as exemplified on six beer samples of different styles. Structural assignments of more than 50 carbohydrate moieties were obtained using (1)H1-(1)H2 groups as structural reporters. Spectroscopically resolved carbohydrates include more than ''20 different'' small carbohydrates with more than 38 isomeric forms in addition to cereal polysaccharide fragments with suspected organoleptic and prebiotic function. Structural motifs at the cleavage sites of starch, β-glucan and arabinoxylan fragments were identified, showing different extent and specificity of enzymatic polysaccharide cleavage during the production of different beer samples. Diffusion ordered spectroscopy supplied independent size information for the characterisation and identification of polysaccharide fragments, indicating the presence especially of high molecular weight arabinoxylan fragments in the final beer. Copyright © 2013 Elsevier Ltd. All rights reserved.

Mucin- and carbohydrate-stimulated adhesion and subproteome changes of the probiotic bacterium Lactobacillus acidophilus NCFM.

PubMed

Celebioglu, Hasan Ufuk; Olesen, Sita Vaag; Prehn, Kennie; Lahtinen, Sampo J; Brix, Susanne; Abou Hachem, Maher; Svensson, Birte

2017-06-23

important for intestinal health and food components, especially non-digestible carbohydrates can beneficially modify the microbiota. In the present study, effects of emerging and established prebiotic carbohydrates on the probiotic potential of Lactobacillus acidophilus NCFM were investigated by testing adhesion to a mucin layer and intestinal cells, and comparing this with changes in abundancy of surface proteins thought to be important for host interactions. Increased adhesion was observed following culturing of the bacterium with fructooligosaccharides, cellobiose or polydextrose, as well as mucin-supplemented glucose as carbon source. Enhanced adhesion ability can prolong bacterial residence in GIT yielding positive health effects. Higher relative abundance of certain surface proteins under various conditions (i.e. grown on cellobiose or mucin-supplemented glucose) suggested involvement of these proteins in adhesion, as confirmed by competition in case of two recombinantly produced moonlighting proteins. Combination of Lactobacillus acidophilus NCFM with different carbohydrates revealed potential bacterial determinants of synbiotic interactions, including stimulation of adhesion. Copyright © 2017 Elsevier B.V. All rights reserved.

Quantum entanglement in photoactive prebiotic systems.

PubMed

Tamulis, Arvydas; Grigalavicius, Mantas

2014-06-01

This paper contains the review of quantum entanglement investigations in living systems, and in the quantum mechanically modelled photoactive prebiotic kernel systems. We define our modelled self-assembled supramolecular photoactive centres, composed of one or more sensitizer molecules, precursors of fatty acids and a number of water molecules, as a photoactive prebiotic kernel systems. We propose that life first emerged in the form of such minimal photoactive prebiotic kernel systems and later in the process of evolution these photoactive prebiotic kernel systems would have produced fatty acids and covered themselves with fatty acid envelopes to become the minimal cells of the Fatty Acid World. Specifically, we model self-assembling of photoactive prebiotic systems with observed quantum entanglement phenomena. We address the idea that quantum entanglement was important in the first stages of origins of life and evolution of the biospheres because simultaneously excite two prebiotic kernels in the system by appearance of two additional quantum entangled excited states, leading to faster growth and self-replication of minimal living cells. The quantum mechanically modelled possibility of synthesizing artificial self-reproducing quantum entangled prebiotic kernel systems and minimal cells also impacts the possibility of the most probable path of emergence of protocells on the Earth or elsewhere. We also examine the quantum entangled logic gates discovered in the modelled systems composed of two prebiotic kernels. Such logic gates may have application in the destruction of cancer cells or becoming building blocks of new forms of artificial cells including magnetically active ones.

Was Ferrocyanide a Prebiotic Reagent?

NASA Technical Reports Server (NTRS)

Keefe, Anthony D.; Miller, Stanley L.

1996-01-01

Hydrogen cyanide is the starting material for a diverse array of prebiotic syntheses, including those of amino acids and purines. Hydrogen cyanide also reacts with ferrous ions to give ferrocyanide, and so it is possible that ferrocyanide was common in the early ocean. This can only be true if the hydrogen cyanide concentration was high enough and the rate of reaction of cyanide with ferrous ions was fast enough. We show experimentally that the rate of formation of ferrocyanide is rapid even at low concentrations of hydrogen cyanide in the pH range 6-8, and therefore an equilibrium calculation is valid. The equilibrium concentrations of ferrocyanide are calculated as a function of hydrogen cyanide concentration, pH and temperature. The steady state concentration of hydrogen cyanide depends on the rate of synthesis by electric discharges and ultraviolet light and the rate of hydrolysis, which depends on pH and temperature. Our conclusions show that ferrocyanide was a major species in the prebiotic ocean only at the highest production rates of hydrogen cyanide in a strongly reducing atmosphere and at temperatures of 0 C or less, although small amounts would have been present at lower hydrogen cyanide production rates. The prebiotic application of ferrocyanide as a source of hydrated electrons, as a photochemical replication process, and in semi-permeable membranes is discussed.

Cashew juice containing prebiotic oligosaccharides.

PubMed

da Silva, Isabel Moreira; Rabelo, Maria Cristiane; Rodrigues, Sueli

2014-09-01

The enzyme dextransucrase in a medium containing sucrose and an acceptor as substrate synthesizes prebiotics oligosaccharides. The cashew apple juice works as a source of acceptors because it is rich in glucose and fructose (enzyme acceptors). The use of cashew apple juice becomes interesting because it aims at harnessing the peduncle of the cashew that is wasted during the nut processing, which is the product of greater economic expression. The production of dextransucrase enzyme was done by fermentative process by inoculating the bacterium Leuconostoc mesenteroides NRRL B512F into a culture medium containing sucrose as the only carbon source. Thus, the aim of this work was the production of prebiotic oligosaccharides by enzymatic process with addition of the dextransucrase enzyme to the clarified cashew apple juice. Dextran yield was favored by the combination of low concentrations of sucrose and reducing sugars. The formation of oligosaccharides was favored by increasing the concentration of reducing sugars and by the combination of high concentrations of sucrose and reducing sugars, the highest concentration of oligosaccharides obtained was 104.73 g/L and the qualitative analysis showed that at concentrations of 25 g/L and 75 g/L of sucrose and reducing sugar, respectively, it is possible to obtain oligosaccharides of degree of polymerization up to 12. The juice containing prebiotic oligosaccharide is a potential new functional beverage.

Weight Loss at a Cost: Implications of High-Protein, Low- Carbohydrate Diets.

ERIC Educational Resources Information Center

Gabel, Kathe A.; Lund, Robin J.

2002-01-01

Addresses three claims of high-protein, low-carbohydrate diets: weight loss is attributed to the composition of the diet; insulin promotes the storage of fat, thereby, by limiting carbohydrates, dieters will decrease levels of insulin and body fat; and weight loss is the result of fat loss. The paper examines relevant scientific reports and notes…

Facilitating the enzymatic saccharification of pulped bamboo residues by degrading the remained xylan and lignin-carbohydrates complexes.

PubMed

Huang, Caoxing; He, Juan; Li, Xin; Min, Douyong; Yong, Qiang

2015-09-01

Kraft pulping was performed on bamboo residues and its impact on the chemical compositions and the enzymatic digestibility of the samples were investigated. To improve the digestibility of sample by degrading the xylan and lignin-carbohydrates complexes (LCCs), xylanase and α-L-arabinofuranosidase (AF) were supplemented with cellulase. The results showed more carbohydrates were remained in the samples pulped with low effective alkali (EA) charge, compared to conventional kraft pulping. When 120 IU/g xylanase and 15 IU/g AF were supplemented with 20 FPU/g cellulase, the xylan degradation yield of the sample pulped with 12% EA charge increased from 68.20% to 88.35%, resulting in an increased enzymatic saccharification efficiency from 58.98% to 83.23%. The amount of LCCs in this sample decreased from 8.63/100C9 to 2.99/100C9 after saccharification with these enzymes. The results indicated that degrading the remained xylan and LCCs in the pulp could improve its enzymatic digestibility. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of xylitol on carbohydrate digesting enzymes activity, intestinal glucose absorption and muscle glucose uptake: a multi-mode study.

PubMed

Chukwuma, Chika Ifeanyi; Islam, Md Shahidul

2015-03-01

The present study investigated the possible mechanism(s) behind the effects of xylitol on carbohydrate digesting enzymes activity, muscle glucose uptake and intestinal glucose absorption using in vitro, ex vivo and in vivo experimental models. The effects of increasing concentrations of xylitol (2.5%-40% or 164.31 mM-2628.99 mM) on alpha amylase and alpha glucosidase activity in vitro and intestinal glucose absorption and muscle glucose uptake were investigated under ex vivo conditions. Additionally, the effects of an oral bolus dose of xylitol (1 g per kg BW) on gastric emptying and intestinal glucose absorption and digesta transit in the different segments of the intestinal tract were investigated in normal and type 2 diabetic rats at 1 hour after dose administration, when phenol red was used as a recovery marker. Xylitol exhibited concentration-dependent inhibition of alpha amylase (IC₅₀ = 1364.04 mM) and alpha glucosidase (IC₅₀ = 1127.52 mM) activity in vitro and small intestinal glucose absorption under ex vivo condition. Xylitol also increased dose dependent muscle glucose uptake with and without insulin, although the uptake was not significantly affected by the addition of insulin. Oral single bolus dose of xylitol significantly delayed gastric emptying, inhibited intestinal glucose absorption but increased the intestinal digesta transit rate in both normal and diabetic rats compared to their respective controls. The data of this study suggest that xylitol reduces intestinal glucose absorption via inhibiting major carbohydrate digesting enzymes, slowing gastric emptying and fastening the intestinal transit rate, but increases muscle glucose uptake in normal and type 2 diabetic rats.

Prebiotic chemistry in clouds

NASA Technical Reports Server (NTRS)

Oberbeck, Verne R.; Marshall, John; Shen, Thomas

1991-01-01

The chemical evolution hypothesis of Woese (1979), according to which prebiotic reactions occurred rapidly in droplets in giant atmospheric reflux columns was criticized by Scherer (1985). This paper proposes a mechanism for prebiotic chemistry in clouds that answers Scherer's concerns and supports Woese's hypothesis. According to this mechanism, rapid prebiotic chemical evolution was facilitated on the primordial earth by cycles of condensation and evaporation of cloud drops containing clay condensation nuclei and nonvolatile monomers. For example, amino acids supplied by, or synthesized during entry of meteorites, comets, and interplanetary dust, would have been scavenged by cloud drops containing clay condensation nuclei and would be polymerized within cloud systems during cycles of condensation, freezing, melting, and evaporation of cloud drops.

Japanese traditional dietary fungus koji Aspergillus oryzae functions as a prebiotic for Blautia coccoides through glycosylceramide: Japanese dietary fungus koji is a new prebiotic.

PubMed

Hamajima, Hiroshi; Matsunaga, Haruka; Fujikawa, Ayami; Sato, Tomoya; Mitsutake, Susumu; Yanagita, Teruyoshi; Nagao, Koji; Nakayama, Jiro; Kitagaki, Hiroshi

2016-01-01

The Japanese traditional cuisine, Washoku, considered to be responsible for increased longevity among the Japanese, comprises various foods fermented with the non-pathogenic fungus Aspergillus oryzae (koji). We have recently revealed that koji contains an abundant amount of glycosylceramide. Intestinal microbes have significant effect on health. However, the effects of koji glycosylceramide on intestinal microbes have not been studied. Glycosylceramide was extracted and purified from koji. C57BL/6N mice were fed a diet containing 1 % purified koji glycosylceramide for 1 week. Nutritional parameters and faecal lipid constituents were analyzed. The intestinal microbial flora of mice on this diet was investigated. Ingested koji glycosylceramide was neither digested by intestinal enzymes nor was it detected in the faeces, suggesting that koji glycosylceramide was digested by the intestinal microbial flora. Intestinal microbial flora that digested koji glycosylceramide had an increased ratio of Blautia coccoides. Stimulation of B. coccoides growth by pure koji glycosylceramide was confirmed in vitro. Koji functions as a prebiotic for B. coccoides through glycosylceramide. Since there are many reports of the effects of B. coccoides on health, an increase in intestinal B. coccoides by koji glycosylceramide might be the connection between Japanese cuisine, intestinal microbial flora, and longevity.

Factors associated with choice of a low-fat or low-carbohydrate diet during a behavioral weight loss intervention☆, ☆☆

PubMed Central

McVay, Megan A.; Voils, Corrine I.; Coffman, Cynthia J.; Geiselman, Paula J.; Kolotkin, Ronette L.; Mayer, Stephanie B.; Smith, Valerie A.; Gaillard, Leslie; Turner, Marsha J.; Yancy, William S.

2016-01-01

Individuals undertaking a weight loss effort have a choice among proven dietary approaches. Factors contributing to choice of either a low-fat/low-calorie diet or a low-carbohydrate diet, two of the most studied and popular dietary approaches, are unknown. The current study used data from participants randomized to the ‘choice’ arm of a trial examining whether being able to choose a diet regimen yields higher weight loss than being randomly assigned to a diet. At study entry, participants attended a group session during which they were provided tailored feedback indicating which diet was most consistent with their food preferences using the Geiselman Food Preference Questionnaire (FPQ), information about both diets, and example meals for each diet. One week later, they indicated which diet they chose to follow during the 48-week study, with the option of switching diets after 12 weeks. Of 105 choice arm participants, 44 (42%) chose the low-fat/low-calorie diet and 61 (58%) chose the low-carbohydrate diet. In bivariate analyses, diet choice was not associated with age, race, sex, education, BMI, or diabetes (all p > 0.05). Low-carbohydrate diet choice was associated with baseline higher percent fat intake (p = 0.007), lower percent carbohydrate intake (p = 0.02), and food preferences consistent with a low-carbohydrate diet according to FPQ (p < 0.0001). In a multivariable logistic regression model, only FPQ diet preference was associated with diet choice (p = 0.001). Reported reasons for diet choice were generally similar for those choosing either diet; however, concerns about negative health effects of the unselected diet was rated as more influential among participants selecting the low-fat diet. Only three low-carbohydrate and two low-fat diet participants switched diets at 12 weeks. Results suggest that when provided a choice between two popular weight loss dietary approaches, an individual's selection is likely influenced by baseline dietary intake pattern

Chemical digestion of low level nuclear solid waste material

DOEpatents

Cooley, Carl R.; Lerch, Ronald E.

1976-01-01

A chemical digestion for treatment of low level combustible nuclear solid waste material is provided and comprises reacting the solid waste material with concentrated sulfuric acid at a temperature within the range of 230.degree.-300.degree.C and simultaneously and/or thereafter contacting the reacting mixture with concentrated nitric acid or nitrogen dioxide. In a special embodiment spent ion exchange resins are converted by this chemical digestion to noncombustible gases and a low volume noncombustible residue.

Intrinsic and extrinsic carbohydrates in the vagina: A short review on vaginal glycogen.

PubMed

Tester, Richard; Al-Ghazzewi, Farage H

2018-06-01

The reasons for (i) the presence and (ii) mechanisms of utilisation of glycogen by the lactic acid bacteria in the human vaginal tract are not well understood. It is probable that the vaginal epithelia produce both glycogen and α-amylase where the enzyme depolymerises the polysaccharide within the vagina itself. Only these depolymerised residues are then utilised for growth by the lactic acid bacteria. The lactic acid bacteria cannot metabolise the glycogen directly due to their incapacity to produce the α-amylase enzyme. These bacteria may, however, metabolise exogenous carbohydrates (such as prebiotics) selectively for growth effectively. These carbohydrate utilisation issues within the vagina are considered in this short review. Copyright © 2018 Elsevier B.V. All rights reserved.

Efficient Anaerobic Digestion of Microalgae Biomass: Proteins as a Key Macromolecule.

PubMed

Magdalena, Jose Antonio; Ballesteros, Mercedes; González-Fernandez, Cristina

2018-05-06

Biogas generation is the least complex technology to transform microalgae biomass into bioenergy. Since hydrolysis has been pointed out as the rate limiting stage of anaerobic digestion, the main challenge for an efficient biogas production is the optimization of cell wall disruption/hydrolysis. Among all tested pretreatments, enzymatic treatments were demonstrated not only very effective in disruption/hydrolysis but they also revealed the impact of microalgae macromolecular composition in the anaerobic process. Although carbohydrates have been traditionally recognized as the polymers responsible for the low microalgae digestibility, protease addition resulted in the highest organic matter solubilization and the highest methane production. However, protein solubilization during the pretreatment can result in anaerobic digestion inhibition due to the release of large amounts of ammonium nitrogen. The possible solutions to overcome these negative effects include the reduction of protein biomass levels by culturing the microalgae in low nitrogen media and the use of ammonia tolerant anaerobic inocula. Overall, this review is intended to evidence the relevance of microalgae proteins in different stages of anaerobic digestion, namely hydrolysis and methanogenesis.

Dietary prebiotics: Current status and new definition

USDA-ARS?s Scientific Manuscript database

In November 2008, a group of scientists met at the 6th Meeting of the International Scientific Association of Probiotics and Prebiotics (ISAPP) in London, Ontario. The aim was to discuss the functionality of prebiotics. As a result of this, it was decided that the prebiotic field as it stands is dom...

[Lipid profile of healthy persons with low-carbohydrate diet].

PubMed

Baumann, Monica; Espeland, Martine Z; Kværner, Ane Sørlie; Bogsrud, Martin Prøven; Retterstøl, Kjetil

2013-06-11

Many Norwegians have embraced the low-carb trend and choose butter and bacon instead of brown bread and carrots. This entails a dramatic change in the total intake of fat and the intake of saturated fat. We have investigated how a low-carb diet can affect the lipid profile in healthy adults with a normal bodyweight. Seven healthy female participants with normal bodyweight underwent a four-week trial of a low-carb diet (< 20-25 grams of carbohydrates/day). Daily diet registrations were made during the trial period, and diet data for three randomly selected days were included in the estimates. Blood samples and weight data were collected as fasting values prior to and after the intervention. Standardised diet data were available for six participants. On a low-carb diet, the energy intake from carbohydrates accounted for a median of 3 (spread: 2-5) per cent of the total energy intake. The intake of fat accounted for 71 (67-78) per cent of total energy, while protein accounted for 26 (19-31) of total energy intake. At baseline, the median value of total cholesterol was 4.1 mmol/L (dispersion: 3.3-5.7) and LDL cholesterol was 2.2 (1.8-3.4) mmol/L. The values increased to 5.2 (3.7-8.8) mmol/L and 3.1 (1.9-6.2) mmol/L for total and LDL cholesterol respectively. The absolute changes correspond to a percentage increase in total cholesterol of 33 (14-71)% and in LDL cholesterol of 41 (9-84)%. Median weight change amounted to -1.2 kg (-2.8-0.6). A diet with little carbohydrate and a great deal of protein and fat resulted in a considerably heightened level of total cholesterol and LDL cholesterol in young, healthy women with a normal bodyweight. The findings indicate that a low-carb diet may have a negative impact on individual risk profiles. However, the study is small-scale and the results must be interpreted with caution.

Effect of weight loss by a low-fat diet and a low-carbohydrate diet on peptide YY levels.

PubMed

Essah, P A; Levy, J R; Sistrun, S N; Kelly, S M; Nestler, J E

2010-08-01

To compare the effects of weight loss by an energy-restricted low-fat diet vs low-carbohydrate diet on serum peptide YY (PYY) levels. 8-Week prospective study of 30 obese adults (mean age: 42.8+/-2.0 years, mean body mass index 35.5+/-0.6 kg m(-2)). After 8 weeks, subjects on the low-carbohydrate diet lost substantially more weight than those on the low-fat diet (5.8 vs 0.99 kg, P<0.001). Weight loss by either diet resulted in a 9% reduction in both mean fasting serum PYY levels (baseline: 103.5+/-8.8 pg ml(-1), after weight loss: 94.1+/-6.5 pg ml(-1), P<0.01) and postprandial area under the curve (AUC) PYY (baseline: (20.5+/-1.5) x 10(3) pg h(-1) ml(-1), after weight loss: mean AUC PYY (18.8+/-1.4) x 10(3) pg h(-1) ml(-1), P<0.001). There was a trend towards lower levels of PYY with greater degrees of weight loss. Reduced PYY levels after weight loss by an energy-restricted low-fat or low-carbohydrate diet likely represents a compensatory response to maintain energy homeostasis and contributes to difficulty in weight loss during energy-restricted diets.

Effect of weight loss by a low-fat diet and a low-carbohydrate diet on peptide YY levels

PubMed Central

Essah, P. A.; Levy, J. R.; Sistrun, S. N.; Kelly, S. M.; Nestler, J. E.

2010-01-01

Objective To compare the effects of weight loss by an energy-restricted low-fat diet versus low-carbohydrate diet on serum peptide YY (PYY) levels. Design 8-week prospective study of 30 obese adults (mean age: 42.8 ± 2.0 years, mean BMI 35.5 ± 0.6 kg/m2). Results After 8 weeks, subjects on the low-carbohydrate diet lost substantially more weight than those on the low-fat diet (5.8 kg vs. 0.99 kg, p<0.001). Weight loss by either diet resulted in a 9% reduction in both mean fasting serum PYY levels (baseline: 103.5 ± 8.8 pg/ml, after weight loss: 94.1 ± 6.5 pg/ml, p<0.01) and postprandial AUC PYY (baseline: (20.5 ± 1.5) × 103 pg·hr−1ml−1, after weight loss: mean AUC PYY (18.8 ± 1.4) × 103 pg·hr−1ml−1 p<0.001). There was a trend towards lower levels of PYY with greater degrees of weight loss. Conclusions Reduced PYY levels after weight loss by an energy-restricted low-fat or low-carbohydrate diet likely represents a compensatory response to maintain energy homeostasis and contributes to difficulty in weight loss during energy-restricted diets. PMID:20351741

Three-year weight change in successful weight losers who lost weight on a low-carbohydrate diet.

PubMed

Phelan, Suzanne; Wyatt, Holly; Nassery, Shirine; Dibello, Julia; Fava, Joseph L; Hill, James O; Wing, Rena R

2007-10-01

The purpose of this study was to evaluate long-term weight loss and eating and exercise behaviors of successful weight losers who lost weight using a low-carbohydrate diet. This study examined 3-year changes in weight, diet, and physical activity in 891 subjects (96 low-carbohydrate dieters and 795 others) who enrolled in the National Weight Control Registry between 1998 and 2001 and reported >or=30-lb weight loss and >or=1 year weight loss maintenance. Only 10.8% of participants reported losing weight after a low-carbohydrate diet. At entry into the study, low-carbohydrate diet users reported consuming more kcal/d (mean +/- SD, 1,895 +/- 452 vs. 1,398 +/- 574); fewer calories in weekly physical activity (1,595 +/- 2,499 vs. 2,542 +/- 2,301); more calories from fat (64.0 +/- 7.9% vs. 30.9 +/- 13.1%), saturated fat (23.8 +/- 4.1 vs. 10.5 +/- 5.2), monounsaturated fat (24.4 +/- 3.7 vs. 11.0 +/- 5.1), and polyunsaturated fat (8.6 +/- 2.7 vs. 5.5 +/- 2.9); and less dietary restraint (10.8 +/- 2.9 vs. 14.9 +/- 3.9) compared with other Registry members. These differences persisted over time. No differences in 3-year weight regain were observed between low-carbohydrate dieters and other Registry members in intent-to-treat analyses (7.0 +/- 7.1 vs. 5.7 +/- 8.7 kg). It is possible to achieve and maintain long-term weight loss using a low-carbohydrate diet. The long-term health effects of weight loss associated with a high-fat diet and low activity level merits further investigation.

Low-carbohydrate diets for type 1 diabetes mellitus: A systematic review.

PubMed

Turton, Jessica L; Raab, Ron; Rooney, Kieron B

2018-01-01

Type 1 diabetes is an autoimmune condition characterised by pancreatic beta cell destruction and absolute insulin deficiency. The strongest predictor of diabetes complications is glycaemic control and achieving HbA1c ≤ 7.0% is the primary management target. However, standard treatment appears to be lacking and adjunctive strategies require consideration. A systematic review was conducted to examine the effect of low-carbohydrate diets on type 1 diabetes management. Four databases were searched from inception until 28 March 2017: MEDLINE; CINAHL; Cochrane Library; and EMBASE. All primary studies containing a methods section (excluding cross-sectional) were included. Reports had to quantitatively measure the effect(s) of a dietary intervention or observed intake over at least two weeks where carbohydrate is below 45% total energy in adults and/or children with type 1 diabetes. The primary outcome was HbA1c and secondary outcomes were severe hypoglycaemia, total daily insulin, BMI, quality of life and mean daily glucose. Seventy-nine full-text articles were assessed for eligibility and nine were included (two randomised controlled trials, four pre-post interventions, two case-series, one case-report). Eight studies reported a mean change in HbA1c with a low-carbohydrate diet. Of these, four reported a non-significant change (P ≥ 0.05) and three reported statistically significant reductions (P < 0.05). Two studies reported severe hypoglycaemia, five reported total insulin, three reported BMI, and one reported blood glucose. Due to the significant heterogeneity of included studies, an overall effect could not be determined. This review presents all available evidence on low-carbohydrate diets for type 1 diabetes and suggests an urgent need for more primary studies.

Probiotics and prebiotics in dermatology.

PubMed

Baquerizo Nole, Katherine L; Yim, Elizabeth; Keri, Jonette E

2014-10-01

The rapid increase in the medical use of probiotics and prebiotics in recent years has confirmed their excellent safety profile. As immune modulators, they have been used in inflammatory skin conditions, such as atopic dermatitis. We review the literature regarding the use of probiotics and prebiotics in dermatology. Probiotics and prebiotics appear to be effective in reducing the incidence of atopic dermatitis in infants, but their role in atopic dermatitis treatment is controversial. Their role in acne, wound healing, and photoprotection is promising, but larger trials are needed before a final recommendation can be made. Copyright © 2014 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Prebiotic effects: metabolic and health benefits.

PubMed

Roberfroid, Marcel; Gibson, Glenn R; Hoyles, Lesley; McCartney, Anne L; Rastall, Robert; Rowland, Ian; Wolvers, Danielle; Watzl, Bernhard; Szajewska, Hania; Stahl, Bernd; Guarner, Francisco; Respondek, Frederique; Whelan, Kevin; Coxam, Veronique; Davicco, Marie-Jeanne; Léotoing, Laurent; Wittrant, Yohann; Delzenne, Nathalie M; Cani, Patrice D; Neyrinck, Audrey M; Meheust, Agnes

2010-08-01

The different compartments of the gastrointestinal tract are inhabited by populations of micro-organisms. By far the most important predominant populations are in the colon where a true symbiosis with the host exists that is a key for well-being and health. For such a microbiota, 'normobiosis' characterises a composition of the gut 'ecosystem' in which micro-organisms with potential health benefits predominate in number over potentially harmful ones, in contrast to 'dysbiosis', in which one or a few potentially harmful micro-organisms are dominant, thus creating a disease-prone situation. The present document has been written by a group of both academic and industry experts (in the ILSI Europe Prebiotic Expert Group and Prebiotic Task Force, respectively). It does not aim to propose a new definition of a prebiotic nor to identify which food products are classified as prebiotic but rather to validate and expand the original idea of the prebiotic concept (that can be translated in 'prebiotic effects'), defined as: 'The selective stimulation of growth and/or activity(ies) of one or a limited number of microbial genus(era)/species in the gut microbiota that confer(s) health benefits to the host.' Thanks to the methodological and fundamental research of microbiologists, immense progress has very recently been made in our understanding of the gut microbiota. A large number of human intervention studies have been performed that have demonstrated that dietary consumption of certain food products can result in statistically significant changes in the composition of the gut microbiota in line with the prebiotic concept. Thus the prebiotic effect is now a well-established scientific fact. The more data are accumulating, the more it will be recognised that such changes in the microbiota's composition, especially increase in bifidobacteria, can be regarded as a marker of intestinal health. The review is divided in chapters that cover the major areas of nutrition research where

Prebiotic synthesis of histidine

NASA Technical Reports Server (NTRS)

Shen, C.; Yang, L.; Miller, S. L.; Oro, J.

1990-01-01

The prebiotic formation of histidine (His) has been accomplished experimentally by the reaction of erythrose with formamidine followed by a Strecker synthesis. In the first step of this reaction sequence, the formation of imidazole-4-acetaldehyde took place by the condensation of erythrose and formamidine, two compounds that are known to be formed under prebiotic conditions. In a second step, the imidazole-4-acetaldehyde was converted to His, without isolation of the reaction products by adding HCN and ammonia to the reaction mixture. LC, HPLC, thermospray liquid chromatography-mass spectrometry, and tandem mass spectrometry were used to identify the product, which was obtained in a yield of 3.5% based on the ratio of His/erythrose. This is a new chemical synthesis of one of the basic amino acids which had not been synthesized prebiotically until now.

Prebiotic evaluation of red seaweed (Kappaphycus alvarezii) using in vitro colon model.

PubMed

Bajury, Dayang Marshitah; Rawi, Muhamad Hanif; Sazali, Iqbal Hakim; Abdullah, Aminah; Sarbini, Shahrul Razid

2017-11-01

Red seaweed (Kappaphycus alvarezii) cultivated from Sabah (RSS) and Langkawi (RSL) were digested using in vitro mouth, gastric and duodenal model. The digested seaweed then fermented in a pH-controlled batch culture system inoculated with human faeces to mimic the distal colon. Bacterial enumeration were monitored using fluorescent in situ hybridisation, and the fermentation end products, the short chain fatty acids (SCFA), were analysed using HPLC. Both RSS and RSL showed significant increase of Bifidobacterium sp.; from log 10 7.96 at 0 h to log 10 8.72 at 24 h, and from log 10 7.96 at 0 h to log 10 8.60 at 24 h, respectively, and shows no significant difference when compared to the Bifidobacterium sp. count at 24 h of inulin fermentation. Both seaweeds also showed significant increase in total SCFA production, particularly acetate and propionate. Overall, this data suggested that K. alvarezii might have the potential as a prebiotic ingredient.

The Effects of a Low-Carbohydrate Diet vs. a Low-Fat Diet on Novel Cardiovascular Risk Factors: A Randomized Controlled Trial

PubMed Central

Hu, Tian; Yao, Lu; Reynolds, Kristi; Whelton, Paul K.; Niu, Tianhua; Li, Shengxu; He, Jiang; Bazzano, Lydia A.

2015-01-01

Increasing evidence supports a low-carbohydrate diet for weight loss and improvement in traditional cardiovascular disease (CVD) markers. Effects on novel CVD markers remain unclear. We examined the effects of a low-carbohydrate diet (<40 g/day; n = 75) versus a low-fat diet (<30% kcal/day from total fat, <7% saturated fat; n = 73) on biomarkers representing inflammation, adipocyte dysfunction, and endothelial dysfunction in a 12 month clinical trial among 148 obese adults free of diabetes and CVD. Participants met with a study dietitian on a periodic basis and each diet group received the same behavioral curriculum which included dietary instruction and supportive counseling. Eighty percent of participants completed the intervention. At 12 months, participants on the low-carbohydrate diet had significantly greater increases in adiponectin (mean difference in change, 1336 ng/mL (95% CI, 342 to 2330 ng/mL); p = 0.009) and greater decreases in intercellular adhesion molecule-1 concentrations (−16.8 ng/mL (−32.0 to −1.6 ng/mL); p = 0.031) than those on the low-fat diet. Changes in other novel CVD markers were not significantly different between groups. In conclusion, despite the differences in weight changes on diets, a low-carbohydrate diet resulted in similar or greater improvement in inflammation, adipocyte dysfunction, and endothelial dysfunction than a standard low-fat diet among obese persons. PMID:26393645

The Effects of a Low-Carbohydrate Diet vs. a Low-Fat Diet on Novel Cardiovascular Risk Factors: A Randomized Controlled Trial.

PubMed

Hu, Tian; Yao, Lu; Reynolds, Kristi; Whelton, Paul K; Niu, Tianhua; Li, Shengxu; He, Jiang; Bazzano, Lydia A

2015-09-17

Increasing evidence supports a low-carbohydrate diet for weight loss and improvement in traditional cardiovascular disease (CVD) markers. Effects on novel CVD markers remain unclear. We examined the effects of a low-carbohydrate diet (<40 g/day; n = 75) versus a low-fat diet (<30% kcal/day from total fat, <7% saturated fat; n = 73) on biomarkers representing inflammation, adipocyte dysfunction, and endothelial dysfunction in a 12 month clinical trial among 148 obese adults free of diabetes and CVD. Participants met with a study dietitian on a periodic basis and each diet group received the same behavioral curriculum which included dietary instruction and supportive counseling. Eighty percent of participants completed the intervention. At 12 months, participants on the low-carbohydrate diet had significantly greater increases in adiponectin (mean difference in change, 1336 ng/mL (95% CI, 342 to 2330 ng/mL); p = 0.009) and greater decreases in intercellular adhesion molecule-1 concentrations (-16.8 ng/mL (-32.0 to -1.6 ng/mL); p = 0.031) than those on the low-fat diet. Changes in other novel CVD markers were not significantly different between groups. In conclusion, despite the differences in weight changes on diets, a low-carbohydrate diet resulted in similar or greater improvement in inflammation, adipocyte dysfunction, and endothelial dysfunction than a standard low-fat diet among obese persons.

Chemical characterization and prebiotic activity of fructo-oligosaccharides from Stevia rebaudiana (Bertoni) roots and in vitro adventitious root cultures.

PubMed

Sanches Lopes, Sheila Mara; Francisco, Mariane Grigio; Higashi, Bruna; de Almeida, Rafaela Takako Ribeiro; Krausová, Gabriela; Pilau, Eduardo Jorge; Gonçalves, José Eduardo; Gonçalves, Regina Aparecida Correia; Oliveira, Arildo José Braz de

2016-11-05

Stevia rebaudiana (Bertoni) is widely studied because of its foliar steviol glycosides. Fructan-type polysaccharides were recently isolated from its roots. Fructans are reserve carbohydrates that have important positive health effects and technological applications in the food industry. The objective of the present study was to isolate and characterize fructo-oligosaccharides (FOSs) from S. rebaudiana roots and in vitro adventitious root cultures and evaluate the potential prebiotic effect of these molecules. The in vitro adventitious root cultures were obtained using a roller bottle system. Chemical analyses (gas chromatography-mass spectrometry, (1)H nuclear magnetic resonance, and off-line electrospray ionization-mass spectrometry) revealed similar chemical properties of FOSs that were obtained from the different sources. The potential prebiotic effects of FOSs that were isolated from S. rebaudiana roots enhanced the growth of both bifidobacteria and lactobacilli, with strains specificity in their fermentation ability. Copyright © 2016 Elsevier Ltd. All rights reserved.

Proximal composition and in vitro digestibility of starch in lima bean (Phaseolus lunatus) varieties.

PubMed

Bello-Pérez, Luis A; Sáyago-Ayerdi, Sonia G; Chávez-Murillo, Carolina E; Agama-Acevedo, Edith; Tovar, Juscelino

2007-11-01

Beans are rich and inexpensive sources of proteins and carbohydrates around the world, but particularly in developing countries. However, many legume varieties are still underutilized. In this study, physical characteristics of the seeds of three Phaseolus lunatus cultivars were characterized. Also, the chemical composition and starch digestibility in the cooked beans were assessed. 'Comba floja' variety exhibited the highest thousand-kernel weight whereas the lowest was found in 'comba violenta'. This agrees with seed dimensions: 'comba floja' had the Longest seeds (16.36 mm) and 'comba violenta' the shortest ones (13.98 mm). All samples exhibited high protein content, but levels in 'comba blanca' variety (216 g kg(-1)) were lower than the in other two cultivars. Total starch (370-380 g kg(-1)) and potentially available starch content (330-340 g kg(-1)) were similar in the three varieties. Resistant starch level in the cooked seeds ranged between 38 and 45 g kg(-1). Low enzymatic hydrolysis indices (HI) were recorded (30.2-35%), indicating a low digestion rate for Phaseolus lunatus starch. HI-based predicted glycemic indices ranged between 34% and 39%, which suggests a 'slow carbohydrate' feature for this legume. Phaseolus lunatus beans appear to be a good source of protein and slow-release carbohydrates with potential benefits for human health. Copyright © 2007 Society of Chemical Industry.

Carbohydrate maldigestion induces necrotizing enterocolitis in preterm pigs

USDA-ARS?s Scientific Manuscript database

Necrotizing enterocolitis (NEC) remains the most severe gastrointestinal disorder in preterm infants. It is associated with the initiation of enteral nutrition and may be related to immature carbohydrate digestive capacity. We tested the hypothesis that a formula containing maltodextrin vs. lactose ...

Carbohydrate maldigestion induces necrotizing enterocolitis in preterm pigs

USDA-ARS?s Scientific Manuscript database

Necrotizing enterocolitis (NEC) is a major gastrointestinal disorder in preterm infants. Key risk factors for NEC are enteral feeding and microbial colonization. Maldigestion of carbohydrate secondary to immature digestive function has been suspected to cause bacterial overgrowth and NEC. We investi...

Applications of prebiotics in food industry: A review.

PubMed

Singla, Vinti; Chakkaravarthi, S

2017-12-01

Benefits of prebiotics for stimulating a healthy intestinal tract are well known. From suppression of pathogens to proliferation of indigenous bacteria of intestines, prebiotics have it all. Since the research on the scope of prebiotics is expanding, new applications are coming up every day thus upgrading the choices consumer has for a healthy living. Incorporation of prebiotics in a wide range of products that food industry offers on shelf is an innovative way to replace fat and sugars along with enhancing the mouthfeel by providing better tongue lubrication. In some cases, the thermal stability of the product is improved along with other sensory, textural and physiological benefits. This paper gives an overview of the various prebiotics available from different sources and their applications in various segments of food industry, notably dairy, beverage, processed fruit-vegetable, bakery, confectionary, extruded snack, sweetener, infant formula, pet food and livestock industry. The effects observed on addition of various prebiotics are also elaborated.

Potentially Prebiotic Syntheses of Condensed Phosphates

NASA Technical Reports Server (NTRS)

Keefe, Anthony D.; Miller, Stanley L.

1996-01-01

In view of the importance of a prebiotic source of high energy phosphates, we have investigated a number of potentially prebiotic processes to produce condensed phosphates from orthophosphate and cyclic trimetaphosphate from tripolyphosphate. The reagents investigated include polymerizing nitriles, acid anhydrides, lactones, hexamethylene tetramine and carbon suboxide. A number of these processes give substantial yields of pyrophosphate from orthophosphate and trimetaphosphate from tripolyphosphate. Although these reactions may have been applicable in local areas, they are not sufficiently robust to have been of importance in the prebiotic open ocean.

Developmental and Digestive Flexibilities in the Midgut of a Polyphagous Pest, the Cotton Bollworm, Helicoverpa armigera

PubMed Central

Sarate, P.J.; Tamhane, V.A.; Kotkar, H.M.; Ratnakaran, N.; Susan, N.; Gupta, V.S.; Giri, A.P.

2012-01-01

Developmental patterns and survival of the cotton bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), a polyphagous insect pest, have been studied with reference to the effect of diet on major gut digestive enzymes (amylases, proteases, and lipases). Significant correlations between nutritional quality of the diet and larval and pupal mass were observed when H. armigera larvae were fed on various host plants viz. legumes (chickpea and pigeonpea), vegetables (tomato and okra), flowers (rose and marigold), and cereals (sorghum and maize). Larvae fed on diets rich in proteins and/or carbohydrates (pigeonpea, chickpea, maize, and sorghum) showed higher larval mass and developed more rapidly than larvae fed on diets with low protein and carbohydrate content (rose, marigold, okra, and tomato). Low calorific value diets like rose and marigold resulted in higher mortality (25–35%) of H. armigera. Even with highly varying development efficiency and larval/pupal survival rates, H. armigera populations feeding on different diets completed their life cycles. Digestive enzymes of H. armigera displayed variable expression levels and were found to be regulated on the basis of macromolecular composition of the diet. Post—ingestive adaptations operating at the gut level, in the form of controlled release of digestive enzymes, might be a key factor contributing to the physiological plasticity in H. armigera. PMID:22954360

Identification of synergistic impacts during anaerobic co-digestion of organic wastes.

PubMed

Astals, S; Batstone, D J; Mata-Alvarez, J; Jensen, P D

2014-10-01

Anaerobic co-digestion has been widely investigated, but there is limited analysis of interaction between substrates. The objective of this work was to assess the role of carbohydrates, protein and lipids in co-digestion behaviour separately, and together. Two sets of batch tests were done, each set consisting of the mono-digestion of three substrates, and the co-digestion of seven mixtures. The first was done with pure substrates--cellulose, casein and olive oil--while in the second slaughterhouse waste--paunch, blood and fat--were used as carbohydrate, protein and lipid sources, respectively. Synergistic effects were mainly improvement of process kinetics without a significant change in biodegradability. Kinetics improvement was linked to the mitigation of inhibitory compounds, particularly fats dilution. The exception was co-digestion of paunch with lipids, which resulted in an improved final yield with model based analysis indicating the presence of paunch improved degradability of the fatty feed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Dietary fiber content influences soluble carbohydrate levels in ruminal fluids.

PubMed

Pinder, R S; Patterson, J A; O'Bryan, C A; Crandall, P G; Ricke, S C

2012-01-01

The soluble carbohydrate concentration of ruminal fluid, as affected by dietary forage content (DFC) and/or ruminally undegradable intake protein content (UIPC), was determined. Four ruminally cannulated steers, in a 4 × 4 Latin square design, were offered diets containing high (75 % of DM) or low (25 % of DM) DFC and high (6 % of DM) or low (5 % of DM) UIPC, in a 2 × 2 factorial arrangement. Zinc-treated SBM was the primary UIP source. Soluble hexose concentration (145.1 μM) in ruminal fluid (RF) of steers fed low DFC diets exhibited a higher trend (P = 0.08) than that (124.5 μM) of steers fed high DFC diets. UIPC did not modulate (P = 0.54) ruminal soluble hexose concentrations. Regardless of diet, soluble hexose concentration declined immediately after feeding and did not rise until 3 h after feeding (P < 0.0001). Cellobiose (≈90 %) and glucose (≈10 %) were the major soluble hexoses present in RF. Maltose was not detected. Soluble glucose concentration (13.0 μM) was not modified by either UIPC (P = 0.40) nor DFC (P = 0.61). However, a DFC by post-prandial time interaction was detected (P = 0.02). Pentose concentrations were greater (P = 0.02) in RF of steers fed high DFC (100.2 μM) than steers fed low DFC (177.0 μM). UIPC did not influence (P = 0.35) soluble pentose concentration. The identity of soluble pentoses in ruminal fluid could not be determined. However, unsubstituted xylose and arabinose were excluded. These data indicate that: (i) soluble carbohydrate concentrations remain in ruminal fluid during digestion and fermentation; (ii) slight diurnal changes began after feeding; (iii) DFC influences the soluble carbohydrate concentration in RF; and (iv) UIPC of these diets does not affect the soluble carbohydrate concentration of RF.

Effects of a low-intensity intervention that prescribed a low-carbohydrate vs. a low-fat diet in obese, diabetic participants.

PubMed

Iqbal, Nayyar; Vetter, Marion L; Moore, Reneé H; Chittams, Jesse L; Dalton-Bakes, Cornelia V; Dowd, Monique; Williams-Smith, Catherine; Cardillo, Serena; Wadden, Thomas A

2010-09-01

Low-carbohydrate diets have been associated with significant reductions in weight and HbA(1c) in obese, diabetic participants who received high-intensity lifestyle modification for 6 or 12 months. This investigation sought to determine whether comparable results to those of short-term, intensive interventions could be achieved over a 24-month study period using a low-intensity intervention that approximates what is feasible in outpatient practice. A total of 144 obese, diabetic participants were randomly assigned to a low-carbohydrate diet (<30 g/day) or to a low fat diet (low-intensity intervention resulted in modest weight loss in both groups at month 24. At this time, participants in the low-carbohydrate group lost 1.5 kg, compared to 0.2 kg in the low-fat group (P = 0.147). Lipids, glycemic indexes, and dietary intake did not differ between groups at month 24 (or at months 6 or 12) (ClinicalTrials.gov number, NCT00108459).

Effects of prebiotics on immune system and cytokine expression.

PubMed

Shokryazdan, Parisa; Faseleh Jahromi, Mohammad; Navidshad, Bahman; Liang, Juan Boo

2017-02-01

Nowadays, use of prebiotics as feed and food additives has received increasing interest because of the beneficial effects of prebiotics on the health of animals and humans. One of the beneficial effects of prebiotics is stimulation of immune system, which can be direct or indirect through increasing population of beneficial microbes or probiotics, especially lactic acid bacteria and bifidobacteria, in the gut. An important mechanism of action of probiotics and prebiotics, by which they can affect the immune system, is changing the expression of cytokines. The present review tried to summarize the findings of studies that investigated the effects of prebiotics on immune system with focusing on their effects on cytokine expression. Generally, most of reviewed studies indicated beneficial effects for prebiotics in terms of improving immune system, by increasing the expression of anti-inflammatory cytokines, while reducing the expressions of proinflammatory cytokines. However, most of studies mainly considered the indirect effects of prebiotics on the immune system (through changing the composition and population of gut microbiota), and their direct effects still need to be further studied using prebiotics with different degree of polymerization in different hosts.

Low-carbohydrate, high-protein score and mortality in a northern Swedish population-based cohort.

PubMed

Nilsson, L M; Winkvist, A; Eliasson, M; Jansson, J-H; Hallmans, G; Johansson, I; Lindahl, B; Lenner, P; Van Guelpen, B

2012-06-01

Long-term effects of carbohydrate-restricted diets are unclear. We examined a low-carbohydrate, high-protein (LCHP) score in relation to mortality. This is a population-based cohort study on adults in the northern Swedish county of Västerbotten. In 37,639 men (1460 deaths) and 39,680 women (923 deaths) from the population-based Västerbotten Intervention Program, deciles of energy-adjusted carbohydrate (descending) and protein (ascending) intake were added to create an LCHP score (2-20 points). Sex-specific hazard ratios (HR) were calculated by Cox regression. Median intakes of carbohydrates, protein and fat in subjects with LCHP scores 2-20 ranged from 61.0% to 38.6%, 11.3% to 19.2% and 26.6% to 41.5% of total energy intake, respectively. High LCHP score (14-20 points) did not predict all-cause mortality compared with low LCHP score (2-8 points), after accounting for saturated fat intake and established risk factors (men: HR for high vs low 1.03 (95% confidence interval (CI) 0.88-1.20), P for continuous = 0.721; women: HR for high vs low 1.10 (95% CI 0.91-1.32), P for continuous = 0.229). For cancer and cardiovascular disease, no clear associations were found. Carbohydrate intake was inversely associated with all-cause mortality, though only statistically significant in women (multivariate HR per decile increase 0.95 (95% CI 0.91-0.99), P = 0.010). Our results do not support a clear, general association between LCHP score and mortality. Studies encompassing a wider range of macronutrient consumption may be necessary to detect such an association.

A global survey of low-molecular weight carbohydrates in lentils

USDA-ARS?s Scientific Manuscript database

Lentils contain a range of low-molecular weight carbohydrates (LMWC); however, they have not been well characterized. The objectives of this study were to (1) determine the concentrations of LMWC in lentils grown in different environments and (2) identify any genetic and environmental effects on tho...

A global survey of low-molecular weight carbohydrates in lentils

USDA-ARS?s Scientific Manuscript database

Lentils contain a range of low-molecular weight carbohydrates (LMWC); however, those have not been well characterized. The objectives of this study were to (1) determine the concentrations of LMWC in lentils grown in six locations, and (2) identify any genetic and environmental effects on those LMWC...

[Specific features of digestive function development in larvae of some salmonid fish].

PubMed

Ershova, T S; Volkova, I V; Zaĭtseva, V F

2004-01-01

We studied the activities of digestive enzymes responsible for the digestion of food carbohydrate and protein components in plant-eating fish at various stages of larval development. The activities of all digestive enzymes tend to rise during larval development. Species specific features of the alimentary canal functioning have been described.

Toward a Personalized Approach in Prebiotics Research.

PubMed

Dey, Moul

2017-01-26

Recent characterization of the human microbiome and its influences on health have led to dramatic conceptual shifts in dietary bioactives research. Prebiotic foods that include many dietary fibers and resistant starches are perceived as beneficial for maintaining a healthy gut microbiota. This article brings forward some current perspectives in prebiotic research to discuss why reporting of individual variations in response to interventions will be important to discern suitability of prebiotics as a disease prevention tool.

Low-protein diets affect ileal amino acid digestibility and gene expression of digestive enzymes in growing and finishing pigs.

PubMed

He, Liuqin; Wu, Li; Xu, Zhiqi; Li, Tiejun; Yao, Kang; Cui, Zhijie; Yin, Yulong; Wu, Guoyao

2016-01-01

The objective of this study was to evaluate effects of dietary crude protein (CP) intake on ileal amino acid digestibilities and expression of genes for digestive enzymes in growing and finishing pigs. In Experiment 1, 18 growing pigs (average initial BW = 36.5 kg) were assigned randomly into one of three treatments (n = 6/treatment group) representing normal (18 % CP), low (15 % CP), and very low (12 % CP) protein intake. In Experiment 2, 18 finishing pigs (average initial BW = 62.3 kg) were allotted randomly into one of three treatments (n = 6/treatment group), representing normal (16 % CP), low (13 % CP) and very low (10 % CP) protein intake. In both experiments, diets with low and very low CP were supplemented with crystalline amino acids to achieve equal content of standardized ileal digestible Lys, Met, Thr, and Trp, and were provided to pigs ad libitum. Daily feed intake, BW, and feed/gain ratios were determined. At the end of each experiment, all pigs were slaughtered to collect pancreas, small-intestine samples, and terminal ileal chymes. Samples were used for determining expression of genes for digestive enzymes and ileal amino acid digestibilities. Growing pigs fed the 12 % CP and 15 % CP diets had lower final body weight (P < 0.01) and ADG (P < 0.0001) when compared with pigs fed the 18 % dietary CP diet. Growing pigs fed with the 12 % CP diet showed higher digestibilities for CP (P < 0.05), DM (P < 0.05), Lys (P < 0.0001), Met (P < 0.01), Cys (P < 0.01), Thr (P < 0.01), Trp (P < 0.05), Val (P < 0.05), Phe (P < 0.05), Ala (P < 0.05), Cys (P < 0.01), and Gly (P < 0.05) than those fed the 18 % CP diet. Finishing pigs fed the 16 % CP diet had a higher (P < 0.01) final body weight than those fed the 10 % CP diet. mRNA levels for digestive enzymes (trypsinogen, chymotrypsin B, and dipeptidases-II and III) differed among the three groups of pigs (P < 0.05), and no difference was noted in the genes expression between control group and lower CP group. These

Effect of low-carbohydrate claims on consumer perceptions about food products' healthfulness and helpfulness for weight management.

PubMed

Labiner-Wolfe, Judith; Jordan Lin, Chung-Tung; Verrill, Linda

2010-01-01

Evaluate effect of low-carbohydrate claims on consumer perceptions about food products' healthfulness and helpfulness for weight management. Experiment in which participants were randomly assigned 1 of 12 front-of-package claim conditions on bread or a frozen dinner. Seven of the 12 conditions also included Nutrition Facts (NF) information. Internet. 4,320 members of a national on-line consumer panel. Exposure to images of a food package. Ratings on Likert scales about perceived healthfulness, helpfulness for weight management, and caloric content. Mean ratings by outcome measure, condition, and product were calculated. Ratings were also used as the dependent measure in analysis of variance models. Participants who saw front-of-package-only conditions rated products bearing low-carbohydrate claims as more helpful for weight management and lower in calories than the same products without a claim. Those who saw the bread with low-carbohydrate claims also rated it as more healthful than those who saw no claim. When the NF label was available and products had the same nutrition profile, participants rated products with low-carbohydrate claims the same as those with no claim. Consumers who do not use the NF panel may interpret low-carbohydrate claims to have meaning beyond the scope of the claim itself. Published by Elsevier Inc.

Inquiry-Based Approach to a Carbohydrate Analysis Experiment

NASA Astrophysics Data System (ADS)

Senkbeil, Edward G.

1999-01-01

The analysis of an unknown carbohydrate in an inquiry-based learning format has proven to be a valuable and interesting undergraduate biochemistry laboratory experiment. Students are given a list of carbohydrates and a list of references for carbohydrate analysis. The references contain a variety of well-characterized wet chemistry and instrumental techniques for carbohydrate identification, but the students must develop an appropriate sequential protocol for unknown identification. The students are required to provide a list of chemicals and procedures and a flow chart for identification before the lab. During the 3-hour laboratory period, they utilize their accumulated information and knowledge to classify and identify their unknown. Advantages of the inquiry-based format are (i) students must be well prepared in advance to be successful in the laboratory, (ii) students feel a sense of accomplishment in both designing and carrying out a successful experiment, and (iii) the carbohydrate background information digested by the students significantly decreases the amount of lecture time required for this topic.

Analysis of Carbohydrate-Carbohydrate Interactions Using Sugar-Functionalized Silicon Nanoparticles for Cell Imaging.

PubMed

Lai, Chian-Hui; Hütter, Julia; Hsu, Chien-Wei; Tanaka, Hidenori; Varela-Aramburu, Silvia; De Cola, Luisa; Lepenies, Bernd; Seeberger, Peter H

2016-01-13

Protein-carbohydrate binding depends on multivalent ligand display that is even more important for low affinity carbohydrate-carbohydrate interactions. Detection and analysis of these low affinity multivalent binding events are technically challenging. We describe the synthesis of dual-fluorescent sugar-capped silicon nanoparticles that proved to be an attractive tool for the analysis of low affinity interactions. These ultrasmall NPs with sizes of around 4 nm can be used for NMR quantification of coupled sugars. The silicon nanoparticles are employed to measure the interaction between the cancer-associated glycosphingolipids GM3 and Gg3 and the associated kD value by surface plasmon resonance experiments. Cell binding studies, to investigate the biological relevance of these carbohydrate-carbohydrate interactions, also benefit from these fluorescent sugar-capped nanoparticles.

The effect of a plant-based low-carbohydrate ("Eco-Atkins") diet on body weight and blood lipid concentrations in hyperlipidemic subjects.

PubMed

Jenkins, David J A; Wong, Julia M W; Kendall, Cyril W C; Esfahani, Amin; Ng, Vivian W Y; Leong, Tracy C K; Faulkner, Dorothea A; Vidgen, Ed; Greaves, Kathryn A; Paul, Gregory; Singer, William

2009-06-08

Low-carbohydrate, high-animal protein diets, which are advocated for weight loss, may not promote the desired reduction in low-density lipoprotein cholesterol (LDL-C) concentration. The effect of exchanging the animal proteins and fats for those of vegetable origin has not been tested. Our objective was to determine the effect on weight loss and LDL-C concentration of a low-carbohydrate diet high in vegetable proteins from gluten, soy, nuts, fruits, vegetables, cereals, and vegetable oils compared with a high-carbohydrate diet based on low-fat dairy and whole grain products. A total of 47 overweight hyperlipidemic men and women consumed either (1) a low-carbohydrate (26% of total calories), high-vegetable protein (31% from gluten, soy, nuts, fruit, vegetables, and cereals), and vegetable oil (43%) plant-based diet or (2) a high-carbohydrate lacto-ovo vegetarian diet (58% carbohydrate, 16% protein, and 25% fat) for 4 weeks each in a parallel study design. The study food was provided at 60% of calorie requirements. Of the 47 subjects, 44 (94%) (test, n = 22 [92%]; control, n = 22 [96%]) completed the study. Weight loss was similar for both diets (approximately 4.0 kg). However, reductions in LDL-C concentration and total cholesterol-HDL-C and apolipoprotein B-apolipoprotein AI ratios were greater for the low-carbohydrate compared with the high-carbohydrate diet (-8.1% [P = .002], -8.7% [P = .004], and -9.6% [P = .001], respectively). Reductions in systolic and diastolic blood pressure were also seen (-1.9% [P = .052] and -2.4% [P = .02], respectively). A low-carbohydrate plant-based diet has lipid-lowering advantages over a high-carbohydrate, low-fat weight-loss diet in improving heart disease risk factors not seen with conventional low-fat diets with animal products.

Low-temperature carbonization and more effective degradation of carbohydrates induced by ferric trichloride.

PubMed

Xia, Juan; Song, Le Xin; Dang, Zheng

2012-07-05

The present work is devoted to an attempt to understand the effect of an inorganic salt such as ferric trichloride (FeCl(3)) on the carbonization and degradation of carbohydrates such as β-cyclodextrin (CD), amylose, and cellulose. Our data revealed two important observations. First, the presence of FeCl(3) led to the occurrence of a low carbonization temperature of 373 K. This is a rare phenomenon, in which carbonization improvement is present even if a small amount of FeCl(3) was added. Experimental results had provided evidence for the fact that a redox process was started during the low-temperature carbonization of β-CD, causing the reduction of FeCl(3) to ferrous chloride (FeCl(2)) by carbon materials formed in the carbonization process in air. However, the reduction process of FeCl(3) produced the in situ composite nanomaterial of Fe-FeCl(2) combination in nitrogen. Second, a molecule-ion interaction emerged between FeCl(3) and the carbohydrates in aqueous solution, resulting in a more effective degradation of the carbohydrates. Moreover, our results demonstrated that FeCl(3) played the role of a catalyst during the degradation of the carbohydrates in solution. We believe that the current work not only has a significant potential application in disposal of waste carbohydrates but also could be helpful in many fields such as environmental protection, biomass energy development, and inorganic composite nanomaterials.

Effects of low-carbohydrate vs low-fat diets on weight loss and cardiovascular risk factors: a meta-analysis of randomized controlled trials.

PubMed

Nordmann, Alain J; Nordmann, Abigail; Briel, Matthias; Keller, Ulrich; Yancy, William S; Brehm, Bonnie J; Bucher, Heiner C

2006-02-13

Low-carbohydrate diets have become increasingly popular for weight loss. However, evidence from individual trials about benefits and risks of these diets to achieve weight loss and modify cardiovascular risk factors is preliminary. We used the Cochrane Collaboration search strategy to identify trials comparing the effects of low-carbohydrate diets without restriction of energy intake vs low-fat diets in individuals with a body mass index (calculated as weight in kilograms divided by the square of height in meters) of at least 25. Included trials had to report changes in body weight in intention-to-treat analysis and to have a follow-up of at least 6 months. Two reviewers independently assessed trial eligibility and quality of randomized controlled trials. Five trials including a total of 447 individuals fulfilled our inclusion criteria. After 6 months, individuals assigned to low-carbohydrate diets had lost more weight than individuals randomized to low-fat diets (weighted mean difference, -3.3 kg; 95% confidence interval [CI], -5.3 to -1.4 kg). This difference was no longer obvious after 12 months (weighted mean difference, -1.0 kg; 95% CI, -3.5 to 1.5 kg). There were no differences in blood pressure. Triglyceride and high-density lipoprotein cholesterol values changed more favorably in individuals assigned to low-carbohydrate diets (after 6 months, for triglycerides, weighted mean difference, -22.1 mg/dL [-0.25 mmol/L]; 95% CI, -38.1 to -5.3 mg/dL [-0.43 to -0.06 mmol/L]; and for high-density lipoprotein cholesterol, weighted mean difference, 4.6 mg/dL [0.12 mmol/L]; 95% CI, 1.5-8.1 mg/dL [0.04-0.21 mmol/L]), but total cholesterol and low-density lipoprotein cholesterol values changed more favorably in individuals assigned to low-fat diets (weighted mean difference in low-density lipoprotein cholesterol after 6 months, 5.4 mg/dL [0.14 mmol/L]; 95% CI, 1.2-10.1 mg/dL [0.03-0.26 mmol/L]). Low-carbohydrate, non-energy-restricted diets appear to be at least as

Toward a Personalized Approach in Prebiotics Research

PubMed Central

Dey, Moul

2017-01-01

Recent characterization of the human microbiome and its influences on health have led to dramatic conceptual shifts in dietary bioactives research. Prebiotic foods that include many dietary fibers and resistant starches are perceived as beneficial for maintaining a healthy gut microbiota. This article brings forward some current perspectives in prebiotic research to discuss why reporting of individual variations in response to interventions will be important to discern suitability of prebiotics as a disease prevention tool. PMID:28134778

Saccharification of bamboo carbohydrates for the production of ethanol

DOE Office of Scientific and Technical Information (OSTI.GOV)

De Menezes, T.J.B.; Azzini, A.; Dos Santos, C.L.M.

1983-04-01

Bamboo carbohydrates were hydrolyzed with commercial amylases and a mixture of fungal culture broths containing cellulolytic and hemicellulolytic enzymes. The effects of cooking temperature and the size of fiber particles were also investigated. It was found that the higher the cooking temperature, the higher the rate of sugar formation and the lower the viscosity of the slurry. Additions of cellulose and hemicellulose digesting enzymes increased the sugar yield and decreased the viscosity of both the cooked and noncooked slurries. A smaller size of particle appeared to favor the average saccharification rate. Although glucose, xylose, and cellobiose were present in themore » hydrolysates, only 50% of the total carbohydrate was digested, and 78.9% of this was converted to reducing sugars. The alcohol efficiency for the fermentation of cooked and noncooked mashes by Saccharomyces was about 85%.« less

Probiotics, prebiotics and colorectal cancer prevention.

PubMed

Ambalam, Padma; Raman, Maya; Purama, Ravi Kiran; Doble, Mukesh

2016-02-01

Colorectal cancer (CRC), the third major cause of mortality among various cancer types in United States, has been increasing in developing countries due to varying diet and dietary habits and occupational hazards. Recent evidences showed that composition of gut microbiota could be associated with the development of CRC and other gut dysbiosis. Modulation of gut microbiota by probiotics and prebiotics, either alone or in combination could positively influence the cross-talk between immune system and microbiota, would be beneficial in preventing inflammation and CRC. In this review, role of probiotics and prebiotics in the prevention of CRC has been discussed. Various epidemiological and experimental studies, specifically gut microbiome research has effectively improved the understanding about the role of probiotics and microbial treatment as anticarcinogenic agents. A few human studies support the beneficial effect of probiotics and prebiotics; hence, comprehensive understanding is urgent to realize the clinical applications of probiotics and prebiotics in CRC prevention. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fad diets and obesity--Part II: An introduction to the theory behind low-carbohydrate diets.

PubMed

Moyad, Mark A

2004-06-01

Low-carbohydrate diets are not only highly popular but also controversial. The theory or general concept behind the low-carbohydrate dietary approach needs to receive more attention to provide more objectivity to this discussion. The theory or concept that actually has some evidence currently lies in the values of the glycemic index (GI) and glycemic load (GL). Basically, the higher the GI, the greater the glucose response. However, the GI system that was originally proffered in 1981 comes with one apparent limitation in that some foods or beverages need to be obtained in enormous amounts in order to observe such a glucose change. Therefore, the newer concept of GL (derived from the GI) is based on a more moderate-portion size and the resultant glucose change with some of the higher GI foods or beverages actually demonstrating a low GL. These and other limitations and some advantages of low-carbohydrate diets with an emphasis of what an actual GI or GL means are discussed.

Hypolipidemic Effect of Red Gram (Cajanus cajan L.) Prebiotic Oligosaccharides in Wistar NIN Rats.

PubMed

Shakappa, Devindra; Talari, Aruna; Rajkumar, Hemalatha; Shujauddin, Mohammed

2017-08-24

The hypolipidemic effect of red gram prebiotics of raffinose family oligosaccharides was studied in Wistar National Institute of Nutrition male rat strain. The study consisted of 36 rats randomly divided into three groups of 12 rats each. For 16 weeks, Group I was fed with the control diet; Group II was fed with a diet containing 3% standard raffinose as the reference group; Group III received the diet containing 3% red gram prebiotics. The results showed that the gain in body weight was low in the red gram prebiotics-supplemented group followed by the control group; highest increase of body weight was seen in the raffinose standard-fed group. Serum glucose levels of the red gram prebiotic-fed group decreased 14.92% compared to the control group and increased 2.07% compared to the reference group. The decrease in serum triglycerides (TG) levels of the red gram prebiotic-fed groups was 32.76% compared to the control group and 33.64% compared to the reference group. Decrease in the serum TC of the red gram-fed animals was 18.51% and 4.63% compared to the control group and the reference group, respectively. Increase in the level of serum high-density lipoprotein cholesterol (HDL-C) in the red gram-fed animals was 18.51% compared to the control group and 4.63% compared to the reference group. The present study can be a proof for the use of prebiotics as a preventive measure for overweight and obesity in humans, and legume prebiotics can be explored as a novel prebiotic product in the consumer market.

Pistachio hull water-soluble polysaccharides as a novel prebiotic agent.

PubMed

Akbari-Alavijeh, Safoura; Soleimanian-Zad, Sabihe; Sheikh-Zeinoddin, Mahmoud; Hashmi, Sarwar

2018-02-01

We isolated and characterized pistachio hull polysaccharides (PHP). The PHP was a heteropolysaccharide mainly contained 75.50% (w/w) total sugar and 9.51% (w/w) uronic acid. As determined by GPC analysis, the polysaccharide with a molecular weight of 3.71×10 6 D (83.2%) was the most dominant fraction. Moreover, HPLC analysis indicated that PHP was predominantly composed of xylose, glucose, arabinose, and fructose with a molar ratio of 1.00:2.50:19.67:28.81. FT-IR and NMR analysis also confirmed the results obtained by HPLC and characterized preliminary structure features of the PHP. Functional properties of the PHP including water holding capacity (WHC: 2.44±0.05g water/g DM), and oil holding capacity (OHC: 11.53±0.04g oil/g DM) were significant compared to inulin used as reference prebiotic (p<0.01). Furthermore, the PHP remained 94.37% undigested in the simulated digestion process and stimulated the growth of L. plantarum PTCC 1896 and L. rhamnosus GG and increased the acetate, propionate and butyrate production over inulin in vitro. Totally, the PHP showed a considerable prebiotic capability and high WHC, OHC suggesting that the PHP is a potent pharmaceutical with good technological properties which can be used in food and drug industries. Copyright © 2017 Elsevier B.V. All rights reserved.

Benefits and hazards of dietary carbohydrate.

PubMed

Connor, William E; Duell, P Barton; Connor, Sonja L

2005-11-01

Since the dawn of civilization, carbohydrate has comprised the largest source of energy in the diet for most populations. The source of the carbohydrate has been from plants in the form of complex carbohydrate high in fiber. Only in affluent cultures has sugar contributed so much of the total energy. When carbohydrate is consumed as a major component of a plant-based diet, a high-carbohydrate, low-fat diet is associated with low plasma levels of total and low-density lipoprotein cholesterol, less coronary heart disease, less diabetes, and less obesity. Very low-carbohydrate (ketogenic) diets may provide short-term solutions but do not lead to a long-term solution for most people.

Effects of disintegration on anaerobic degradation of sewage excess sludge in downflow stationary fixed film digesters.

PubMed

Engelhart, M; Krüger, M; Kopp, J; Dichtl, N

2000-01-01

The effects of mechanical disintegration on anaerobic digestibility of sewage excess sludge in downflow stationary fixed film (DSFF) digesters were investigated on laboratory scale. Mechanical pretreatment using a high pressure homogenizer led to significantly enhanced concentrations of soluble proteins and carbohydrates in the feed sludge. Using DSFF digesters with two different tubular plastic media as support material it was shown that a stable digestion process could be achieved at hydraulic retention times (HRT) down to 5 days. Compared to conventional digesters at 10 d and 15 d HRT respectively, the degradation of volatile solids was enhanced up to 25%, also resulting in a higher specific biogas production. Further investigations on degradation of soluble proteins and carbohydrates showed that a slowly degradable fraction of carbohydrates was released via disintegration. Using the distribution of chain length and the concentrations of volatile fatty acids as process parameters, the dependability on the HRT and the degree of disintegration (the release of soluble COD) predominated the effects of specific surface area of the support media.

Performance of methanogenic reactors in temperature phased two-stage anaerobic digestion of swine wastewater.

PubMed

Kim, Woong; Shin, Seung Gu; Cho, Kyungjin; Lee, Changsoo; Hwang, Seokhwan

2012-12-01

The present study investigated the shifts in the chemical profiles of a two-phase anaerobic digestion system in methanogenic and acidogenic reactors for the treatment of swine wastewater. Acidogenic and methanogenic digesters were used with overall HRTs ranging from 27 to 6 d. In the optimized thermophilic/acidogenic phase throughout the entire experimental period, VS was reduced by 13.8% (1.6%); however, COD hardly decreased because of the thermophilic hydrolysis of organic materials, such as carbohydrates, proteins, and lipids, without any significant consumption of volatile fatty acids. In the methanogenic/mesophilic phase, COD was reduced by 65.8 (1.1)% compared to a 47.4 (2.9)% reduction in VS reduction efficiency with the gradual increase in methane production during a methanogenic HRT between 25 and 10 d. A high protein degradation rate was observed in the optimized acidogenic phase, which is assumed to be due to the low content of carbohydrates in raw swine wastewater as well as the readily thermophilic hydrolysis of proteins. Two-phase systems of anaerobic digestion consisting of optimized thermophilic and mesophilic methanogenic digesters showed a stable performance with respect to VS reduction efficiency with OLRs less than 3 g VS/L·d, in other words, more than 10 days of methanogenic HRT in this study. Copyright © 2012 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

[The participation of ethanol in induction of carbohydrates metabolism disturbances].

PubMed

Orywal, Karolina; Jelski, Wojciech; Szmitkowski, Maciej

2009-07-01

Alcohol and products of its metabolism lead to impairment of many organs functions, what cause systemic and local carbohydrates metabolism disturbances. Abusing of alcohol induces changes in pancreatic digestive enzymes secretion, what contributes to development of chronic alcoholic pancreatitis. Alcohol can cause secondary diabetes, what is result of pancreatic beta-cells damage and is a risk factor for type 2 diabetes. Alcohol cause liver cells degeneration and induction of many metabolic disturbances especially carbohydrates.

Potential Prebiotic Oligosaccharide Mixtures from Acidic Hydrolysis of Rice Bran and Cassava Pulp.

PubMed

Hansawasdi, Chanida; Kurdi, Peter

2017-12-01

Two agricultural wastes, rice bran and cassava pulp were subjected to acidic hydrolysis by 2 M sulfuric acid which resulted in hemicellulosic oligosaccharide mixtures. Monosaccharide component analysis of these mixtures revealed that the oligosaccharides of rice bran acid hydrolysate (RAHF) composed of glucose and arabinose while cassava pulp acid hydrolysate (CAHF) was found to be comprised of glucose, galactose and arabinose. Both RAHF and CAHF were able to fuel all of the tested three Lactobacillus, five Bifidobacterium and three Bacteroides strains indicating the prebiotic potential of these oligosaccharide mixtures. Moreover, Lb. gasseri grew significantly better on RAHF than on inulin, a benchmark prebiotic oligo- and polysaccharide mixture. When the digestibility of RAHF and CAHF were tested it was found that these oligosaccharide mixtures were only slightly hydrolyzed upon exposure to simulated human gastric (by less than 8%) and pancreatic juices (by less than 3%). Additionally, most sensory attributes of the above obtained oligosaccharide mixtures supplemented two model cereal drink formulations were generally not different from those of the control, while the overall acceptance was not affected significantly in one cereal drink formulation.

The prebiotic concept and human health: a changing landscape with riboflavin as a novel prebiotic candidate?

PubMed

Steinert, R E; Sadaghian Sadabad, M; Harmsen, H J M; Weber, P

2016-12-01

Emerging evidence suggests that the gut microbiota has a critical role in both the maintenance of human health and the pathogenesis of many diseases. Modifying the colonic microbiota using functional foods has attracted significant research effort and product development. The pioneering concept of prebiotics, as introduced by Gibson and Roberfroid in the 1990s, emphasized the importance of diet in the modulation of the gut microbiota and its relationships to human health. Increasing knowledge of the intestinal microbiota now suggests a more comprehensive definition. This paper briefly reviews the basics of the prebiotic concept with a discussion of recent attempts to refine the concept to open the door for novel prebiotic food ingredients, such as polyphenols, minerals and vitamins.

The preliminary study of prebiotic potential of Polish wild mushroom polysaccharides: the stimulation effect on Lactobacillus strains growth.

PubMed

Nowak, Renata; Nowacka-Jechalke, Natalia; Juda, Marek; Malm, Anna

2018-06-01

According to the vast body of evidence demonstrating that the intestinal microbiota is undoubtedly linked with overall health, including cancer risk, searching for functional foods and novel prebiotic influencing on beneficial bacteria is necessary. The present study aimed to investigate the potential of polysaccharides from 53 wild-growing mushrooms to stimulate the growth of Lactobacillus acidophilus and Lactobacillus rhamnosus and to determine the digestibility of polysaccharide fractions. Mushroom polysaccharides were precipitated with ethanol from aqueous extracts. Determination of growth promoting activity of polysaccharides was performed in U-shaped 96-plates in an ELISA reader in relation to the reference strain of L. acidophilus and two clinical strains of L. rhamnosus. The digestibility of mushroom polysaccharides was investigated in vitro by exposing them to artificial human gastric juice. Obtained results revealed that fungal polysaccharides stimulate the growth of Lactobacillus strains stronger than commercially available prebiotics like inulin or fructooligosaccharides. Moreover, selected polysaccharides were subjected to artificial human gastric juice and remain undigested in more than 90%. Obtained results indicate that mushroom polysaccharides are able to pass through the stomach unchanged, reaching the colon and stimulating the growth of beneficial bacteria. Majority of 53 polysaccharide fractions were analysed for the first time in our study. Overall, our findings suggest that polysaccharide fractions from edible mushrooms might be useful in producing functional foods and nutraceuticals.

Effects of a plant-based high-carbohydrate/high-fiber diet versus high-monounsaturated fat/low-carbohydrate diet on postprandial lipids in type 2 diabetic patients.

PubMed

De Natale, Claudia; Annuzzi, Giovanni; Bozzetto, Lutgarda; Mazzarella, Raffaella; Costabile, Giuseppina; Ciano, Ornella; Riccardi, Gabriele; Rivellese, Angela A

2009-12-01

To search for a better dietary approach to treat postprandial lipid abnormalities and improve glucose control in type 2 diabetic patients. According to a randomized crossover design, 18 type 2 diabetic patients (aged 59 +/- 5 years; BMI 27 +/- 3 kg/m(2)) (means +/- SD) in satisfactory blood glucose control on diet or diet plus metformin followed a diet relatively rich in carbohydrates (52% total energy), rich in fiber (28 g/1,000 kcal), and with a low glycemic index (58%) (high-carbohydrate/high-fiber diet) or a diet relatively low in carbohydrate (45%) and rich in monounsaturated fat (23%) (low-carbohydrate/high-monounsaturated fat diet) for 4 weeks. Thereafter, they shifted to the other diet for 4 more weeks. At the end of each period, plasma glucose, insulin, lipids, and lipoprotein fractions (separated by discontinuous density gradient ultracentrifugation) were determined on blood samples taken at fasting and over 6 h after a test meal having a similar composition as the corresponding diet. In addition to a significant decrease in postprandial plasma glucose, insulin responses, and glycemic variability, the high-carbohydrate/high-fiber diet also significantly improved the primary end point, since it reduced the postprandial incremental areas under the curve (IAUCs) of triglyceride-rich lipoproteins, in particular, chylomicrons (cholesterol IAUC: 0.05 +/- 0.01 vs. 0.08 +/- 0.02 mmol/l per 6 h; triglycerides IAUC: 0.71 +/- 0.35 vs. 1.03 +/- 0.58 mmol/l per 6 h, P < 0.05). A diet rich in carbohydrate and fiber, essentially based on legumes, vegetables, fruits, and whole cereals, may be particularly useful for treating diabetic patients because of its multiple effects on different cardiovascular risk factors, including postprandial lipids abnormalities.

"Most people are simply not designed to eat pasta": evolutionary explanations for obesity in the low-carbohydrate diet movement.

PubMed

Knight, Christine

2011-09-01

Low-carbohydrate diets, notably the Atkins Diet, were particularly popular in Britain and North America in the late 1990s and early 2000s. On the basis of a discourse analysis of bestselling low-carbohydrate diet books, I examine and critique genetic and evolutionary explanations for obesity and diabetes as they feature in the low-carbohydrate literature. Low-carbohydrate diet books present two distinct neo-Darwinian explanations of health and body-weight. First, evolutionary nutrition is based on the premise that the human body has adapted to function best on the diet eaten in the Paleolithic era. Second, the thrifty gene theory suggests that feast-or-famine conditions during human evolutionary development naturally selected for people who could store excess energy as body fat for later use. However, the historical narratives and scientific arguments presented in the low-carbohydrate literature are beset with generalisations, inconsistencies and errors. These result, I argue, from the use of the primitive as a discursive "blank slate" onto which to project ideals perceived to be lacking in contemporary industrialised life.

Enrichment of pasta with faba bean does not impact glycemic or insulin response but can enhance satiety feeling and digestive comfort when dried at very high temperature.

PubMed

Greffeuille, Valérie; Marsset-Baglieri, Agnès; Molinari, Nicolas; Cassan, Denis; Sutra, Thibault; Avignon, Antoine; Micard, Valérie

2015-09-01

Enrichment of durum wheat pasta with legume flour enhances their protein and essential amino acid content, especially lysine content. However, despite its nutritional potential, the addition of a legume alters the rheological properties of pasta. High temperature drying of pasta reduces this negative effect by strengthening its protein network. The aim of our study was to determine if these changes in the pasta structure alter its in vitro carbohydrate digestibility, in vivo glycemic, insulin and satiety responses. We also investigated if high temperature drying of pasta can reduce the well-known digestive discomfort associated with the consumption of legume grains. Fifteen healthy volunteers consumed three test meals: durum wheat pasta dried at a low temperature (control), and pasta enriched with 35% faba bean dried at a low and at a very high temperature. When enriched with 35% legume flour, pasta maintained its nutritionally valuable low glycemic and insulin index, despite its weaker protein network. Drying 35% faba bean pasta at a high temperature strengthened its protein network, and decreased its in vitro carbohydrate digestion with no further decrease in its in vivo glycemic or insulin index. Drying pasta at a very high temperature reduced digestive discomfort and enhanced self-reported satiety, and was not associated with a modification of energy intake in the following meal.

Source of carbohydrate and metabolizable lysine and methionine in the diet of recently weaned dairy calves on digestion and growth.

PubMed

Hill, T M; Quigley, J D; Bateman, H G; Aldrich, J M; Schlotterbeck, R L

2016-04-01

Two 56-d trials with weaned Holstein dairy calves (initially 72 ± 1.8 kg of body weight, 58 to 60 d of age) fed 95% concentrate and 5% chopped grass hay diets were conducted. Each trial used 96 calves (4 calves/pen). During 15 of the last 21 d of the first trial and 10 of 14 d of the second and third week of the second trial, fecal samples were taken to estimate digestibility using acid-insoluble ash as an internal marker. Digestibility estimates along with 56-d average daily gain (ADG), hip width change, body condition score, and fecal score were analyzed with pen as the experimental unit. In trial 1, a textured diet (19% crude protein) with high starch [52% starch, 13% neutral detergent fiber (NDF)] based on whole corn and oats or a pelleted low-starch (20% starch, 35% NDF), high-digestible fiber diet were used. Within starch level, diets were formulated from supplemental soybean meal or soybean meal with blood meal and Alimet (Novus International Inc., St. Charles, MO) to provide 2 metabolizable protein levels (1 and 1.07% metabolizable lysine plus methionine). The 4 treatments were analyzed as a completely randomized design with a 2 by 2 factorial arrangement (6 pens/diet). In trial 2, all pelleted diets (19% crude protein) were fed. Diets were based on soybean hulls, wheat middlings, or corn, which contained increasing concentrations of starch (13, 27, and 42% starch and 42, 23, and 16% NDF, respectively; 8 pens/diet). Contrast statements were constructed to separate differences in the means (soybean hulls plus wheat middlings vs. corn; soybean hulls vs. wheat middlings). In trial 1, intake of organic matter (OM) did not differ. Digestibility of OM was greater in calves fed high- versus low starch-diets. Digestibility of NDF and starch were less in calves fed the high- versus low-starch diets. Calf ADG and hip width change were greater for high- versus low-starch diets. Source of protein did not influence digestibility or ADG. In trial 2, intake of OM was not

Prebiotics for the prevention of allergies: A systematic review and meta-analysis of randomized controlled trials.

PubMed

Cuello-Garcia, C; Fiocchi, A; Pawankar, R; Yepes-Nuñez, J J; Morgano, G P; Zhang, Y; Agarwal, A; Gandhi, S; Terracciano, L; Schünemann, H J; Brozek, J L

2017-11-01

Prevalence of allergic diseases in infants is approximately 10% reaching 20 to 30% in those with an allergic first-degree relative. Prebiotics are selectively fermented food ingredients that allow specific changes in composition/activity of the gastrointestinal microflora. They modulate immune responses, and their supplementation has been proposed as an intervention to prevent allergies. To assess in pregnant women, breastfeeding mothers, and infants (populations) the effect of supplementing prebiotics (intervention) versus no prebiotics (comparison) on the development of allergic diseases and to inform the World Allergy Organization guidelines. We performed a systematic review of studies assessing the effects of prebiotic supplementation with an intention to prevent the development of allergies. Of 446 unique records published until November 2016 in Cochrane, MEDLINE, and EMBASE, 22 studies fulfilled a priori specified criteria. We did not find any studies of prebiotics given to pregnant women or breastfeeding mothers. Prebiotic supplementation in infants, compared to placebo, had the following effects: risk of developing eczema (RR: 0.68, 95% CI: 0.40 to 1.15), wheezing/asthma (RR, 0.37; 95% CI: 0.17 to 0.80), and food allergy (RR: 0.28, 95% CI: 0.08 to 1.00). There was no evidence of an increased risk of any adverse effects (RR: 1.01, 95% CI: 0.92 to 1.10). Prebiotic supplementation had little influence growth rate (MD: 0.92 g per day faster with prebiotics, 95% CI: 0 to 1.84) and the final infant weight (MD: 0.10 kg higher with prebiotics, 95% CI: -0.09 to 0.29). The certainty of these estimates is very low due to risk of bias and imprecision of the results. Currently available evidence on prebiotic supplementation to reduce the risk of developing allergies is very uncertain. © 2017 John Wiley & Sons Ltd.

Simulating the UV Environment For the Synthesis of Prebiotic Molecules

NASA Astrophysics Data System (ADS)

Ranjan, S.; Sasselov, D.

2014-03-01

UV radiation plays a key role in the era of biogenesis. The young Sun was more UV-active than the modern Sun (Ribas et al. 2010), and the Earth lacked an ozone layer, implying a larger UV flux both on Earth, as well as on asteroids/comets. Ultraviolet radiation can help drive prebiotic molecule synthesis (e.g., Chyba et al. 1992; Powner et al. 2009) or destroy biologically important molecules (e.g., Johns et al. 1967). These effects are wavelength dependent: they are sensitive to ionzation, bond, and ro-vibrational transition energies of biologically relevant molecules and their precursors. When simulating the environment at biogenesis it is therefore important to ensure realistic levels of UV input, in both magnitude and spectral shape. Many laboratory simulations of biomolecule synthesis under prebiotic conditions to date have been done with atomic lamps (e.g., Powner et al. 2007). These lamps are safe, stable, and affordable UV sources, well-suited for initial studies. However, their emission spectra are a poor match to prebiotic conditions: low-pressure lamps are characterized by line emission, while higher-pressure lamps do not well-reproduce the spectrum of the young Sun. In this paper, we present spectra that are more realistic approximations to prebiotic conditions. Using published opacity lists and atmospheric models, we compute the attenuation of the flux from a young Sunanalog due to water, and from the present-day Sun due to a planetary atmosphere. We compare these spectra to those emitted by lamps used in studies today, and explore the potential biological implications of the differences. We conclude by discussing possibilities for better simulating the prebiotic UV environment in lab setups.

Evaluation of Glyceraldehyde Under Simulated Prebiotic Conditions

NASA Astrophysics Data System (ADS)

Aguilar-Ovando, E.; Buhse, T.; Negrón-Mendoza, A.

2017-07-01

The aim of this work is to compare the behavior under irradiation of solid and aqueous DL-glyceraldehyde simulating prebiotic conditions. The results show the formation of sugar-like products of prebiotic significance as function of irradiation dose.

Lignocentric analysis of a carbohydrate-producing lignocellulosic biorefinery process.

PubMed

Narron, Robert H; Han, Qiang; Park, Sunkyu; Chang, Hou-Min; Jameel, Hasan

2017-10-01

A biologically-based lignocellulosic biorefinery process for obtaining carbohydrates from raw biomass was investigated across six diverse biomasses (three hardwoods & three nonwoods) for the purpose of decoding lignin's influence on sugar production. Acknowledging that lignin could positively alter the economics of an entire process if valorized appropriately, we sought to correlate the chemical properties of lignin within the process to the traditional metrics associated with carbohydrate production-cellulolytic digestibility and total sugar recovery. Based on raw carbohydrate, enzymatic recovery ranged from 40 to 64% w/w and total recovery ranged from 70 to 87% w/w. Using nitrobenzene oxidation to quantify non-condensed lignin structures, it was found that raw hardwoods bearing increasing non-condensed S/V ratios (2.5-5.1) render increasing total carbohydrate recovery from hardwood biomasses. This finding indicates that the chemical structure of hardwood lignin influences the investigated biorefinery process' ability to generate carbohydrates from a given raw hardwood feedstock. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of High vs Low Glycemic Index of Dietary Carbohydrate on Cardiovascular Disease Risk Factors and Insulin Sensitivity

PubMed Central

Sacks, Frank M.; Carey, Vincent J.; Anderson, Cheryl A. M.; Miller, Edgar R.; Copeland, Trisha; Charleston, Jeanne; Harshfield, Benjamin J.; Laranjo, Nancy; McCarron, Phyllis; Swain, Janis; White, Karen; Yee, Karen; Appel, Lawrence J.

2015-01-01

IMPORTANCE Foods that have similar carbohydrate content can differ in the amount they raise blood glucose. The effects of this property, called the glycemic index, on risk factors for cardiovascular disease and diabetes are not well understood. OBJECTIVE To determine the effect of glycemic index and amount of total dietary carbohydrate on risk factors for cardiovascular disease and diabetes. DESIGN, SETTING, AND PARTICIPANTS Randomized crossover-controlled feeding trial conducted in research units in academic medical centers, in which 163 overweight adults (systolic blood pressure, 120–159 mm Hg) were given 4 complete diets that contained all of their meals, snacks, and calorie-containing beverages, each for 5 weeks, and completed at least 2 study diets. The first participant was enrolled April 1, 2008; the last participant finished December 22, 2010. For any pair of the 4 diets, there were 135 to 150 participants contributing at least 1 primary outcome measure. INTERVENTIONS (1) A high–glycemic index (65% on the glucose scale), high-carbohydrate diet (58% energy); (2) a low–glycemic index (40%), high-carbohydrate diet; (3) a high–glycemic index, low-carbohydrate diet (40% energy); and (4) a low–glycemic index, low-carbohydrate diet. Each diet was based on a healthful DASH-type diet. MAIN OUTCOMES AND MEASURES The 5 primary outcomes were insulin sensitivity, determined from the areas under the curves of glucose and insulin levels during an oral glucose tolerance test; levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides; and systolic blood pressure. RESULTS At high dietary carbohydrate content, the low– compared with high–glycemic index level decreased insulin sensitivity from 8.9 to 7.1 units (−20%, P = .002); increased LDL cholesterol from 139 to 147 mg/dL (6%, P ≤ .001); and did not affect levels of HDL cholesterol, triglycerides, or blood pressure. At low carbohydrate content, the

[Glycemic, insulinemic index, glycemic load of soy beverage with low and high content of carbohydrates].

PubMed

Torres y Torres, Nimbe; Palacios-González, Berenice; Noriega-López, Lilia; Tovar-Palacio, Armando R

2006-01-01

Consumption of soy has increased in Western countries due to the benefits on health and the attitude of the people to consume natural products as alternative to the use of pharmacological therapies. However, there is no evidence whether the consumption of 25 g of soy protein as recommended by the Food and Drug Administration has some effect on glucose absorption and consequently on insulin secretion. The aim of the present study was to determine glycemic index (GI), insulinemic index (InIn), and glycemic load (GL) of several soy beverages containing low or high concentration of carbohydrates, and compare them with other foods such as peanuts, whole milk, soluble fiber and a mixed meal on GI and InIn. The results showed that soy beverages had low or moderate GI, depending of the presence of other compounds like carbohydrates and fiber. Consumption of soy beverages with low concentration of carbohydrates produced the lowest insulin secretion. Therefore, these products can be recommended in obese and diabetic patients. Finally soy beverages should contain low maltodextrins concentration and be added of soluble fiber.

Prebiotic Supplementation has Only Minimal Effects on Growth Efficiency, Intestinal Health and Disease Resistance of Westslope Cutthroat Trout Oncorhynchus clarkii lewisi Fed 30% Soybean Meal.

PubMed

Sealey, Wendy M; Conley, Zachariah B; Bensley, Molly

2015-01-01

Prebiotics have successfully been used to prevent infectious diseases in aquaculture and there is an increasing amount of literature that suggests that these products can also improve alternative protein utilization and digestion. Therefore, the objective of this study was to examine whether prebiotic supplementation increased the growth efficiency, intestinal health, and disease resistance of cutthroat trout fed a high level of dietary soybean meal. To achieve this objective, juvenile Westslope cutthroat trout (Oncorhynchus clarkii lewisi) were fed a practical type formulation with 0 or 30% dietary soybean meal with or without the commercial prebiotic (Grobiotic-A) prior to experimental exposure to Flavobacterium psychrophilum. Juvenile Westslope cutthroat trout (initial weight 7.8 g/fish ±SD of 0.5 g) were stocked at 30 fish/tank in 75 L tanks with six replicate tanks per diet and fed their respective diets for 20 weeks. Final weights of Westslope cutthroat trout were affected by neither dietary soybean meal inclusion level (P = 0.9582) nor prebiotic inclusion (P = 0.9348) and no interaction was observed (P = 0.1242). Feed conversion ratios were similarly not affected by soybean meal level (P = 0.4895), prebiotic inclusion (P = 0.3258) or their interaction (P = 0.1478). Histological examination of the distal intestine of Westslope cutthroat trout demonstrated increases in inflammation due to both increased soybean meal inclusion level (P = 0.0038) and prebiotic inclusion (P = 0.0327) without significant interaction (P = 0.3370). Feeding dietary soybean meal level at 30% increased mortality of F. psychrophilum cohabitation challenged Westslope cutthroat trout (P = 0.0345) while prebiotic inclusion tended to decrease mortality (P = 0.0671). These results indicate that subclinical alterations in intestinal inflammation levels due to high dietary inclusion levels of soybean meal could predispose Westslope cutthroat

Effect of a low-carbohydrate diet on respiratory quotient of infants with chronic lung disease.

PubMed

Suteerojntrakool, Orapa; Sanguanrungsirikul, Sompol; Sritippayawan, Suchada; Jantarabenjakul, Watsamon; Sirimongkol, Pathama; Chomtho, Sirinuch

2015-01-01

To compare the respiratory quotient in infants with chronic lung disease before and after receiving a modular diet with slightly lower carbohydrate content. Infants with chronic lung disease from the King Chulalongkorn Memorial Hospital were enrolled and assessed for nutritional status, severity of chronic lung disease and dietary intake. Indirect calorimetry was performed using a custom-made airtight canopy with O2 and CO2 sensors. Respiratory quotient (RQ) was calculated from VCO2/VO2 during the period they were fed low carbohydrates (37% of total calories) for at least 24 hours vs. a standard diet (47% carbohydrate). These two formulas were similar in terms of caloric density and protein content. Each patient received at least 100-150 kcal/ kg/day during the study period. Respiratory quotients of the same patient receiving the two diets were compared by using Wilcoxon signed-rank test. A total of 14 patients (median age 7 months, range 1-26 months) were recruited. Twelve children had weight for age Z-score below-2SD. Their median weight for age Z-score, length for age Z-score and weight for length Z-score were -2.89, -3.08 and -1.24, respectively. The median RQ measured during the low carbohydrate diet was 0.96 (interquartile range 0.95-0.97), significantly lower than the median RQ during the standard diet, which was 1.04 (0.97-1.10). However, the respiratory rate revealed no significant difference. Two participants with underlying gastroesophageal reflux disease showed higher RQ after low carbohydrate formula feeding, which might be a result of hypersecretion due to its high fat content. Diet with slightly lower carbohydrate content can reduce the RQ in infants with chronic lung disease compared to the standard enteral formula. A 10-percent reduction of carbohydrate content may provide a sizeable effect in this group of patients. Nevertheless, the clinical significance of this finding requires further investigation.

A 100-year review: Carbohydrates - characterization, digestion, and utilization

USDA-ARS?s Scientific Manuscript database

Our knowledge of the role of carbohydrates in dairy cattle nutrition has advanced substantially during the 100 years in which the Journal of Dairy Science has been published. In this review, we traced the history of scientific investigation and discovery from crude fiber, nitrogen-free extract, and ...

Low-Carbohydrate-High-Fat Diet: Can it Help Exercise Performance?

PubMed

Chang, Chen-Kang; Borer, Katarina; Lin, Po-Ju

2017-02-01

Low-carbohydrate-high-fat (LCHF) diets have been used as a means of weight loss and control of symptoms in several clinical conditions. There is emerging evidence that the metabolic changes induced by LCHF diets enhance endurance performance. The aims of this review are to examine the evidence of LCHF diets in improving various aspects of athletic performance. Long-term LCHF dietary intake may help control body weight and fat mass while maintaining lean body mass in athletes in weight-sensitive sports. LCHF-adapted endurance athletes can reach the maximal fat oxidation rate of approximately 1.5 g/min, with a lower carbohydrate oxidation rate and similar muscle glycogen content and a resynthesis rate compared to their counterparts consuming high-carbohydrate-low-fat (HCLF) diets. The elevated fat oxidation rate and glycogen sparing effect may improve performance in ultra-endurance events. These metabolic changes may also prevent the decline in performance in later stages of repeated high-intensity movements, in which the aerobic metabolism becomes more important. However, elevated blood concentrations of non-esterified fatty acids and ammonia during exercise after LCHF diets may lead to early development of central fatigue. It appears that at least several months of adaptation to a LCHF diet are required for the metabolic changes and restoration of muscle glycogen to occur. Further investigations on LCHF diets are needed regarding (1) performance after weight loss in weight-categorized sports; (2) repeated high-intensity exercise performance; (3) development of central fatigue during endurance events; (4) perceptual-motor performance during prolonged intermittent sports; and (5) ideal dietary fatty acid compositions.

Probiotics and prebiotics associated with aquaculture: A review.

PubMed

Akhter, Najeeb; Wu, Bin; Memon, Aamir Mahmood; Mohsin, Muhammad

2015-08-01

There is a rapidly growing literature, indicating success of probiotics and prebiotics in immunomodulation, namely the stimulation of innate, cellular and humoral immune response. Probiotics are considered to be living microorganisms administered orally and lead to health benefits. These Probiotics are microorganisms in sufficient amount to alter the microflora (by implantation or colonization) in specific host's compartment exerting beneficial health effects at this host. Nevertheless, Prebiotics are indigestible fiber which enhances beneficial commensally gut bacteria resulting in improved health of the host. The beneficial effects of prebiotics are due to by-products derived from the fermentation of intestinal commensal bacteria. Among the many health benefits attributed to probiotics and prebiotics, the modulation of the immune system is one of the most anticipated benefits and their ability to stimulate systemic and local immunity, deserves attention. They directly enhance the innate immune response, including the activation of phagocytosis, activation of neutrophils, activation of the alternative complement system, an increase in lysozyme activity, and so on. Prebiotics acting as immunosaccharides directly impact on the innate immune system of fish and shellfish. Therefore, both probiotics and prebiotics influence the immunomodulatory activity boosting up the health benefits in aquatic animals. Copyright © 2015 Elsevier Ltd. All rights reserved.

Low-carbohydrate, high-protein, high-fat diet alters small peripheral artery reactivity in metabolic syndrome patients.

PubMed

Merino, Jordi; Kones, Richard; Ferré, Raimon; Plana, Núria; Girona, Josefa; Aragonés, Gemma; Ibarretxe, Daiana; Heras, Mercedes; Masana, Luis

2014-01-01

Low carbohydrate diets have become increasingly popular for weight loss. Although they may improve some metabolic markers, particularly in type 2 diabetes mellitus (T2D) or metabolic syndrome (MS), their net effect on vascular function remains unclear. Evaluate the relation between dietary macronutrient composition and the small artery reactive hyperaemia index (saRHI), a marker of small artery vascular function, in a cohort of MS patients. This cross-sectional study included 160 MS patients. Diet was evaluated by a 3-day food-intake register and reduced to a novel low-carbohydrate diet score (LCDS). Physical examination, demographic, biochemical and anthropometry parameters were recorded, and saRHI was measured in each patient. Individuals in the lowest LCDS quartile (Q1; 45% carbohydrate, 19% protein, 31% fat) had higher saRHI values than those in the top quartile (Q4; 30% carbohydrate, 25% protein, 43% fat) (1.84±0.42 vs. 1.55±0.25, P=.012). These results were similar in T2D patients (Q1=1.779±0.311 vs. Q4=1.618±0.352, P=.011) and also in all of the MS components, except for low HDLc. Multivariate analysis demonstrated that individuals in the highest LCDS quartile, that is, consuming less carbohydrates, had a significantly negative coefficient of saRHI which was independent of confounders (HR: -0.747; 95%CI: 0.201, 0.882; P=.029). These data suggest that a dietary pattern characterized by a low amount of carbohydrate, but reciprocally higher amounts of fat and protein, is associated with poorer vascular reactivity in patients with MS and T2D. Copyright © 2013 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

A randomized trial comparing a very low carbohydrate diet and a calorie-restricted low fat diet on body weight and cardiovascular risk factors in healthy women.

PubMed

Brehm, Bonnie J; Seeley, Randy J; Daniels, Stephen R; D'Alessio, David A

2003-04-01

Untested alternative weight loss diets, such as very low carbohydrate diets, have unsubstantiated efficacy and the potential to adversely affect cardiovascular risk factors. Therefore, we designed a randomized, controlled trial to determine the effects of a very low carbohydrate diet on body composition and cardiovascular risk factors. Subjects were randomized to 6 months of either an ad libitum very low carbohydrate diet or a calorie-restricted diet with 30% of the calories as fat. Anthropometric and metabolic measures were assessed at baseline, 3 months, and 6 months. Fifty-three healthy, obese female volunteers (mean body mass index, 33.6 +/- 0.3 kg/m(2)) were randomized; 42 (79%) completed the trial. Women on both diets reduced calorie consumption by comparable amounts at 3 and 6 months. The very low carbohydrate diet group lost more weight (8.5 +/- 1.0 vs. 3.9 +/- 1.0 kg; P < 0.001) and more body fat (4.8 +/- 0.67 vs. 2.0 +/- 0.75 kg; P < 0.01) than the low fat diet group. Mean levels of blood pressure, lipids, fasting glucose, and insulin were within normal ranges in both groups at baseline. Although all of these parameters improved over the course of the study, there were no differences observed between the two diet groups at 3 or 6 months. beta- Hydroxybutyrate increased significantly in the very low carbohydrate group at 3 months (P = 0.001). Based on these data, a very low carbohydrate diet is more effective than a low fat diet for short-term weight loss and, over 6 months, is not associated with deleterious effects on important cardiovascular risk factors in healthy women.

Chemical Characterization of Potentially Prebiotic Oligosaccharides in Brewed Coffee and Spent Coffee Grounds.

PubMed

Tian, Tian; Freeman, Samara; Corey, Mark; German, J Bruce; Barile, Daniela

2017-04-05

Oligosaccharides are indigestible carbohydrates widely present in mammalian milk and in some plants. Milk oligosaccharides are associated with positive health outcomes; however, oligosaccharides in coffee have not been extensively studied. We investigated the oligosaccharides and their monomeric composition in dark roasted coffee beans, brewed coffee, and spent coffee grounds. Oligosaccharides with a degree of polymerization ranging from 3 to 15, and their constituent monosaccharides, were characterized and quantified. The oligosaccharides identified were mainly hexoses (potentially galacto-oligosaccharides and manno-oligosaccharides) containing a heterogeneous mixture of glucose, arabinose, xylose, and rhamnose. The diversity of oligosaccharides composition found in these coffee samples suggests that they could have selective prebiotic activity toward specific bacterial strains able to deconstruct the glycosidic bonds and utilize them as a carbon source.

A Critical Look at Prebiotics Within the Dietary Fiber Concept.

PubMed

Verspreet, Joran; Damen, Bram; Broekaert, Willem F; Verbeke, Kristin; Delcour, Jan A; Courtin, Christophe M

2016-01-01

This article reviews the current knowledge of the health effects of dietary fiber and prebiotics and establishes the position of prebiotics within the broader context of dietary fiber. Although the positive health effects of specific fibers on defecation, reduction of postprandial glycemic response, and maintenance of normal blood cholesterol levels are generally accepted, other presumed health benefits of dietary fibers are still debated. There is evidence that specific dietary fibers improve the integrity of the epithelial layer of the intestines, increase the resistance against pathogenic colonization, reduce the risk of developing colorectal cancer, increase mineral absorption, and have a positive impact on the immune system, but these effects are neither generally acknowledged nor completely understood. Many of the latter effects are thought to be particularly elicited by prebiotics. Although the prebiotic concept evolved significantly during the past two decades, the line between prebiotics and nonprebiotic dietary fiber remains vague. Nevertheless, scientific evidence demonstrating the health-promoting potential of prebiotics continues to accumulate and suggests that prebiotic fibers have their rightful place in a healthy diet.

Recent Development of Prebiotic Research—Statement from an Expert Workshop

PubMed Central

La Fata, Giorgio; Rastall, Robert A.; Lacroix, Christophe; Harmsen, Hermie J. M.; Mohajeri, M. Hasan; Weber, Peter

2017-01-01

A dietary prebiotic is defined as ‘a substrate that is selectively utilized by host microorganisms conferring a health benefit’. Although this definition evolved concomitantly with the knowledge and technological developments that accrued in the last twenty years, what qualifies as prebiotic continues to be a matter of debate. In this statement, we report the outcome of a workshop where academic experts working in the field of prebiotic research met with scientists from industry. The workshop covered three main topics: (i) evolution of the prebiotic concept/definition; (ii) the gut modeling in vitro technology PolyFermS to study prebiotic effects; and (iii) the potential novel microbiome-modulating effects associated with vitamins. The future of prebiotic research is very promising. Indeed, the technological developments observed in recent years provide scientists with powerful tools to investigate the complex ecosystem of gut microbiota. Combining multiple in vitro approaches with in vivo studies is key to understanding the mechanisms of action of prebiotics consumption and their potential beneficial effects on the host. PMID:29261110

Assessment of the prebiotic effect of quinoa and amaranth in the human intestinal ecosystem.

PubMed

Gullón, Beatriz; Gullón, Patricia; Tavaria, Freni K; Yáñez, Remedios

2016-09-14

Quinoa and amaranth belong to the group of the so called "superfoods" and have a nutritional composition that confers multiple benefits. In this work, we explored the possibility of these foods exhibiting a prebiotic effect. These pseudocereals were subjected to an in vitro digestion and used as carbon sources in batch cultures with faecal human inocula. The effects on the microbiota composition and their metabolic products were determined by assessment of variations in pH, short-chain fatty acid (SCFA) production and changes in the dynamic bacterial populations by fluorescence in situ hybridization (FISH). After 48 h of incubation, the total SCFAs were 106.5 mM for quinoa and 108.83 mM for amaranth, in line with the decrease in pH. Considerable differences (p < 0.05) were found in certain microbial groups, including Bifidobacterium spp., Lactobacillus-Enterococcus, Atopobium, Bacteroides-Prevotella, Clostridium coccoides-Eubacterium rectale, Faecalibacterium prausnitzii and Roseburia intestinalis. Our research suggests that these pseudocereals can have the prebiotic potential and that their intake may improve dysbiosis or maintain the gastrointestinal health through a balanced intestinal microbiota, although additional studies are necessary.

Modulation of the human gut microbiota by dietary fibres occurs at the species level.

PubMed

Chung, Wing Sun Faith; Walker, Alan W; Louis, Petra; Parkhill, Julian; Vermeiren, Joan; Bosscher, Douwina; Duncan, Sylvia H; Flint, Harry J

2016-01-11

Dietary intake of specific non-digestible carbohydrates (including prebiotics) is increasingly seen as a highly effective approach for manipulating the composition and activities of the human gut microbiota to benefit health. Nevertheless, surprisingly little is known about the global response of the microbial community to particular carbohydrates. Recent in vivo dietary studies have demonstrated that the species composition of the human faecal microbiota is influenced by dietary intake. There is now potential to gain insights into the mechanisms involved by using in vitro systems that produce highly controlled conditions of pH and substrate supply. We supplied two alternative non-digestible polysaccharides as energy sources to three different human gut microbial communities in anaerobic, pH-controlled continuous-flow fermentors. Community analysis showed that supply of apple pectin or inulin resulted in the highly specific enrichment of particular bacterial operational taxonomic units (OTUs; based on 16S rRNA gene sequences). Of the eight most abundant Bacteroides OTUs detected, two were promoted specifically by inulin and six by pectin. Among the Firmicutes, Eubacterium eligens in particular was strongly promoted by pectin, while several species were stimulated by inulin. Responses were influenced by pH, which was stepped up, and down, between 5.5, 6.0, 6.4 and 6.9 in parallel vessels within each experiment. In particular, several experiments involving downshifts to pH 5.5 resulted in Faecalibacterium prausnitzii replacing Bacteroides spp. as the dominant sequences observed. Community diversity was greater in the pectin-fed than in the inulin-fed fermentors, presumably reflecting the differing complexity of the two substrates. We have shown that particular non-digestible dietary carbohydrates have enormous potential for modifying the gut microbiota, but these modifications occur at the level of individual strains and species and are not easily predicted a priori

Innovative analytical tools to characterize prebiotic carbohydrates of functional food interest.

PubMed

Corradini, Claudio; Lantano, Claudia; Cavazza, Antonella

2013-05-01

Functional foods are one of the most interesting areas of research and innovation in the food industry. A functional food or functional ingredient is considered to be any food or food component that provides health benefits beyond basic nutrition. Recently, consumers have shown interest in natural bioactive compounds as functional ingredients in the diet owing to their various beneficial effects for health. Water-soluble fibers and nondigestible oligosaccharides and polysaccharides can be defined as functional food ingredients. Fructooligosaccharides (FOS) and inulin are resistant to direct metabolism by the host and reach the caecocolon, where they are used by selected groups of beneficial bacteria. Furthermore, they are able to improve physical and structural properties of food, such as hydration, oil-holding capacity, viscosity, texture, sensory characteristics, and shelf-life. This article reviews major innovative analytical developments to screen and identify FOS, inulins, and the most employed nonstarch carbohydrates added or naturally present in functional food formulations. High-performance anion-exchange chromatography with pulsed electrochemical detection (HPAEC-PED) is one of the most employed analytical techniques for the characterization of those molecules. Mass spectrometry is also of great help, in particularly matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), which is able to provide extensive information regarding the molecular weight and length profiles of oligosaccharides and polysaccharides. Moreover, MALDI-TOF-MS in combination with HPAEC-PED has been shown to be of great value for the complementary information it can provide. Some other techniques, such as NMR spectroscopy, are also discussed, with relevant examples of recent applications. A number of articles have appeared in the literature in recent years regarding the analysis of inulin, FOS, and other carbohydrates of interest in the field and

The importance of dietary carbohydrates.

PubMed

Sánchez-Castillo, Claudia P; Hudson, Geoffrey J; Englyst, Hans N; Dewey, Peter; James, W Philip T

2002-12-01

Forty years ago carbohydrates (CHO) were regarded as a simple energy source whereas they are now recognized as important food components. The human diet contains a wide range of CHO, the vast majority of which are of plant origin. Modern techniques based on chemical classification of dietary CHO replaced the traditional "by difference" measurement. They provide a logical basis for grouping into categories of specific nutritional importance. The physiological effects of dietary CHO are highly dependent on the rate and extent of digestion and absorption in the small intestine and fermentation in the large intestine, interactions which promote human health. Current knowledge of the fate of dietary CHO means that the potentially undesirable properties of many modern foods could be altered by using processing techniques that yield foods with more intact plant cell wall structures. Such products would more closely resemble the foods in the pre-agriculture diet with respect to the rate of digestion and absorption of CHO in the small intestine. The potentially detrimental physiological consequences of eating sugars and starch that are rapidly digested and absorbed in the small intestine suggest that, as fibre, the form, as well as the amount of starch should be considered. Increasing consumer awareness of the relationship between diet and health has led to demands for more widespread nutrition labelling. The entry "carbohydrate" is required in most countries, and the value is usually obtained "by difference" and used in the calculation of energy content. However, the value provides no nutritional information per se. Food labels should provide values that aid consumers in selecting a healthy diet.

Fiber, prebiotics, and diarrhea: what, why, when and how.

PubMed

Generoso, Simone de Vasconcelos; Lages, Priscilla Ceci; Correia, Maria Isabel Toulsson Davisson

2016-07-15

Dietary fiber and prebiotics have been the focus of research and discussion for decades, but there are still pending concepts and definitions, in particular when addressing their use in the prevention and treatment of diarrhea. The purpose of this review is to present the latest advances in the understanding of dietary fiber and prebiotics, to review their proven role in the management of diarrhea, and to postulate the best timings and optimal doses. The use of prebiotics has encompassed not only prevention but also the treatment of distinct types of diarrhea, at different treatment moments, and with regard to various different markers of outcome. Furthermore, the description of soluble fibers claiming to be prebiotics, and vice versa, has too often been the tone in the literature, which has led to misconceptions in classification and, consequently, confusion over the interpretation of results. It remains difficult to establish a consensus about the real impact of fiber and prebiotics on the prevention and therapy of diarrhea. The review highlights the overlapping concepts of fiber and prebiotics, and supports the need for adequate individualization of their use, according to the goal - either prevention or treatment of diarrhea - as well as the optimal timing and dose to be used. Nonetheless, viscous soluble fibers seem to be the best option in treating diarrhea, whereas prebiotics are more important in preventing and avoiding recurrence.

In vitro prebiotic effects of seaweed polysaccharides

NASA Astrophysics Data System (ADS)

Chen, Xiaolin; Sun, Yuhao; Hu, Linfeng; Liu, Song; Yu, Huahua; Xing, Rong'e.; Li, Rongfeng; Wang, Xueqin; Li, Pengcheng

2017-09-01

Although prebiotic activities of alginate and agar oligosaccharides isolated from seaweeds have been reported, it remains unknown whether seaweed polysaccharides have prebiotic activity. In this study, we isolated polysaccharides from four species of seaweeds, such as Grateloupia filicina (GFP), Eucheuma spinosum (ESP), Ulva pertusa (UPP), and Ascophyllum nodosum (ANP), and characterized their structures and prebiotic effects in vitro. The results showed that these polysaccharides were different in total sugar and sulfate contents as well as monosaccharide composition. GFP and ESP significantly promoted bifidobacterium proliferation and 0.1% ESP and 0.4% GFP resulted in the highest proliferation rates of beneficial bacteria, whereas UPP and ANP inhibited the growth of beneficial bacteria at all tested concentrations (0.1%-0.5%). The different behaviors of the four seaweed-originated polysaccharides might be reflected by differences in monosaccharide composition and structure. Therefore, polysaccharides isolated from GFP and ESP could be utilized as prebiotics. However, more studies must be carried out in vivo.

Prebiotics as immunostimulants in aquaculture: a review.

PubMed

Song, Seong Kyu; Beck, Bo Ram; Kim, Daniel; Park, John; Kim, Jungjoon; Kim, Hyun Duk; Ringø, Einar

2014-09-01

Prebiotics are indigestible fibers that increase beneficial gut commensal bacteria resulting in improvements of the host's health. The beneficial effects of prebiotics are due to the byproducts generated from their fermentation by gut commensal bacteria. In this review, the direct effects of prebiotics on the innate immune system of fish are discussed. Prebiotics, such as fructooligosaccharide, mannanoligosaccharide, inulin, or β-glucan, are called immunosaccharides. They directly enhance innate immune responses including: phagocytic activation, neutrophil activation, activation of the alternative complement system, increased lysozyme activity, and more. Immunosaccharides directly activate the innate immune system by interacting with pattern recognition receptors (PRR) expressed on innate immune cells. They can also associate with microbe associated molecular patterns (MAMPs) to activate innate immune cells. However, the underlying mechanisms involved in innate immune cell activation need to be further explored. Many studies have indicated that immunosaccharides are beneficial to both finfish and shellfish. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nutrition, Health, and Regulatory Aspects of Digestible Maltodextrins

PubMed Central

Hofman, Denise L.; van Buul, Vincent J.; Brouns, Fred J. P. H.

2016-01-01

Digestible maltodextrins are low-sweet saccharide polymers consisting of D-glucose units linked primarily linearly with alpha-1,4 bonds, but can also have a branched structure through alpha-1,6 bonds. Often, maltodextrins are classified by the amount of reducing sugars present relative to the total carbohydrate content; between 3 and 20 percent in the case of digestible maltodextrins. These relatively small polymers are used as food ingredients derived by hydrolysis from crops naturally rich in starch. Through advances in production technology, the application possibilities in food products have improved during the last 20 years. However, since glucose from digested maltodextrins is rapidly absorbed in the small intestine, the increased use has raised questions about potential effects on metabolism and health. Therefore, up-to-date knowledge concerning production, digestion, absorption, and metabolism of maltodextrins, including potential effects on health, were reviewed. Exchanging unprocessed starch with maltodextrins may lead to an increased glycemic load and therefore post meal glycaemia, which are viewed as less desirable for health. Apart from beneficial food technological properties, its use should accordingly also be viewed in light of this. Finally, this review reflects on regulatory aspects, which differ significantly in Europe and the United States, and, therefore, have implications for communication and marketing. PMID:25674937

Nutrition, Health, and Regulatory Aspects of Digestible Maltodextrins.

PubMed

Hofman, Denise L; van Buul, Vincent J; Brouns, Fred J P H

2016-09-09

Digestible maltodextrins are low-sweet saccharide polymers consisting of D-glucose units linked primarily linearly with alpha-1,4 bonds, but can also have a branched structure through alpha-1,6 bonds. Often, maltodextrins are classified by the amount of reducing sugars present relative to the total carbohydrate content; between 3 and 20 percent in the case of digestible maltodextrins. These relatively small polymers are used as food ingredients derived by hydrolysis from crops naturally rich in starch. Through advances in production technology, the application possibilities in food products have improved during the last 20 years. However, since glucose from digested maltodextrins is rapidly absorbed in the small intestine, the increased use has raised questions about potential effects on metabolism and health. Therefore, up-to-date knowledge concerning production, digestion, absorption, and metabolism of maltodextrins, including potential effects on health, were reviewed. Exchanging unprocessed starch with maltodextrins may lead to an increased glycemic load and therefore post meal glycaemia, which are viewed as less desirable for health. Apart from beneficial food technological properties, its use should accordingly also be viewed in light of this. Finally, this review reflects on regulatory aspects, which differ significantly in Europe and the United States, and, therefore, have implications for communication and marketing.

The effect of wheat prebiotics on the gut bacterial population and iron status of iron deficient broiler chickens

PubMed Central

2014-01-01

Background Currently, there is a lot of interest in improving gut health, and consequently increasing Fe absorption, by managing the colonic microbial population. This is traditionally done by the consumption of probiotics, live microbial food supplements. However, an alternative, and often very effective approach, is the consumption of food ingredients known as prebiotics. Fructans and arabinoxylans are naturally occurring non-digestible oligosaccharides in wheat that exhibit prebiotic properties and may enhance intestinal iron (Fe) absorption. The aim of this study was to assess the effect of prebiotics from wheat on Fe bioavailability in vitro (Caco-2 cells) and in vivo (broiler chickens, Gallus gallus). Methods In the current study, the effect of intra-amniotic administration of wheat samples extracts at 17 d of embryonic incubation on the Fe status and possible changes in the bacterial population in intestinal content of broiler hatchlings were investigated. A group of 144 eggs were injected with the specified solution (1 ml per egg) into the amniotic fluid. Immediately after hatch (21 d) and from each treatment group, 10 chicks were euthanized and their small intestine, liver and cecum were removed for relative mRNA abundance of intestinal Fe related transporters, relative liver ferritin amounts and bacterial analysis of cecal content, respectively. Results The in vivo results are in agreement with the in vitro observations, showing no differences in the hatchling Fe status between the treatment groups, as Fe bioavailability was not increased in vitro and no significant differences were measured in the intestinal expression of DMT1, Ferroportin and DcytB in vivo. However, there was significant variation in relative amounts of bifidobacteria and lactobacilli in the intestinal content between the treatments groups, with generally more bifidobacteria being produced with increased prebiotic content. Conclusions In this study we showed that prebiotics naturally

The effect of wheat prebiotics on the gut bacterial population and iron status of iron deficient broiler chickens.

PubMed

Tako, Elad; Glahn, Raymond P; Knez, Marija; Stangoulis, James Cr

2014-06-13

Currently, there is a lot of interest in improving gut health, and consequently increasing Fe absorption, by managing the colonic microbial population. This is traditionally done by the consumption of probiotics, live microbial food supplements. However, an alternative, and often very effective approach, is the consumption of food ingredients known as prebiotics. Fructans and arabinoxylans are naturally occurring non-digestible oligosaccharides in wheat that exhibit prebiotic properties and may enhance intestinal iron (Fe) absorption. The aim of this study was to assess the effect of prebiotics from wheat on Fe bioavailability in vitro (Caco-2 cells) and in vivo (broiler chickens, Gallus gallus). In the current study, the effect of intra-amniotic administration of wheat samples extracts at 17 d of embryonic incubation on the Fe status and possible changes in the bacterial population in intestinal content of broiler hatchlings were investigated. A group of 144 eggs were injected with the specified solution (1 ml per egg) into the amniotic fluid. Immediately after hatch (21 d) and from each treatment group, 10 chicks were euthanized and their small intestine, liver and cecum were removed for relative mRNA abundance of intestinal Fe related transporters, relative liver ferritin amounts and bacterial analysis of cecal content, respectively. The in vivo results are in agreement with the in vitro observations, showing no differences in the hatchling Fe status between the treatment groups, as Fe bioavailability was not increased in vitro and no significant differences were measured in the intestinal expression of DMT1, Ferroportin and DcytB in vivo. However, there was significant variation in relative amounts of bifidobacteria and lactobacilli in the intestinal content between the treatments groups, with generally more bifidobacteria being produced with increased prebiotic content. In this study we showed that prebiotics naturally found in wheat grains/bread products

Low-Carbohydrate-High-Fat Diet: Can it Help Exercise Performance?

PubMed Central

Borer, Katarina; Lin, Po-Ju

2017-01-01

Abstract Low-carbohydrate-high-fat (LCHF) diets have been used as a means of weight loss and control of symptoms in several clinical conditions. There is emerging evidence that the metabolic changes induced by LCHF diets enhance endurance performance. The aims of this review are to examine the evidence of LCHF diets in improving various aspects of athletic performance. Long-term LCHF dietary intake may help control body weight and fat mass while maintaining lean body mass in athletes in weight-sensitive sports. LCHF-adapted endurance athletes can reach the maximal fat oxidation rate of approximately 1.5 g/min, with a lower carbohydrate oxidation rate and similar muscle glycogen content and a resynthesis rate compared to their counterparts consuming high-carbohydrate-low-fat (HCLF) diets. The elevated fat oxidation rate and glycogen sparing effect may improve performance in ultra-endurance events. These metabolic changes may also prevent the decline in performance in later stages of repeated high-intensity movements, in which the aerobic metabolism becomes more important. However, elevated blood concentrations of non-esterified fatty acids and ammonia during exercise after LCHF diets may lead to early development of central fatigue. It appears that at least several months of adaptation to a LCHF diet are required for the metabolic changes and restoration of muscle glycogen to occur. Further investigations on LCHF diets are needed regarding (1) performance after weight loss in weight-categorized sports; (2) repeated high-intensity exercise performance; (3) development of central fatigue during endurance events; (4) perceptual-motor performance during prolonged intermittent sports; and (5) ideal dietary fatty acid compositions. PMID:28469746

The microstructure of starchy food modulates its digestibility.

PubMed

Tian, Jinhu; Ogawa, Yukiharu; Shi, John; Chen, Shiguo; Zhang, Huiling; Liu, Donghong; Ye, Xingqian

2018-06-05

Starch is the main carbohydrate in human nutrition and shows a range of desired food properties. It has been demonstrated that fast digestion of starchy food can induce many health issues (e.g., hyperglycaemia, diabetes, etc.); therefore, how to modulate its digestion is an interesting topic. Previous studies have revealed that the microstructure and digestibility of starchy food of different botanical origin or from multiple processes are quite different; modulating starch digestion by retaining or altering its microstructure may be effective. In the present review, the current knowledge of the relationship between microstructural changes to starchy food and its digestibility at molecular, cell and tissue, and food processing levels is summarized. New technologies focused on microstructure studies and ways to manipulate food microstructure to modulate starch digestibility are also reviewed. In particular, some insights focusing on the future study of microstructure and the digestibility of starchy food are also suggested.

A critical review of low-carbohydrate diets in people with Type 2 diabetes.

PubMed

van Wyk, H J; Davis, R E; Davies, J S

2016-02-01

The efficacy of low-carbohydrate diets (LCD) in people with Type 2 diabetes has divided the nutrition community. This review seeks to re-examine the available data to clarify understanding. A comprehensive search of databases was used to identify meta-analyses of LCD in Type 2 diabetes. To improve the quality of the studies analysed, the following inclusion criteria were applied: randomized control trials ≥ 4 weeks in people aged > 18 years with Type 2 diabetes; a carbohydrate intake ≤ 45% of total energy intake per day; and a dietary intake assessment at the end of the study. The resulting studies were subjected to a thematic analysis. Nine meta-analyses were identified containing 153 studies. Twelve studies met our amended inclusion criteria. There were no significant differences in metabolic markers, including glycaemic control, between the two diets, although weight loss with a LCD was greater in one study. Carbohydrate intake at 1 year in very LCD (< 50 g of carbohydrates) ranged from 132 to 162 g. In some studies, the difference between diets was as little as 8 g/day of carbohydrates. Total energy intake remains the dietary predictor of body weight. A LCD appears no different from a high-carbohydrate diet in terms of metabolic markers and glycaemic control. Very LCDs may not be sustainable over a medium to longer term as carbohydrate intake in diets within studies often converged toward a more moderate level. The variable quality of studies included in earlier meta-analyses likely explains the previous inconsistent findings between meta-analyses. © 2015 The Authors. Diabetic Medicine © 2015 Diabetes UK.

Catalytic effects of glycine on prebiotic divaline and diproline formation.

PubMed

Plankensteiner, Kristof; Reiner, Hannes; Rode, Bernd M

2005-07-01

The catalytic effects of the simple amino acid glycine on the formation of diproline and divaline in the prebiotically relevant salt-induced peptide formation (SIPF) reaction was investigated in systems of different amino acid starting concentrations and using the two enantiomeric forms of the respective amino acid. Results show an improved applicability of the SIPF reaction to prebiotic conditions, especially at low amino acid concentrations, as presumably present in a primordial scenario, and indicate excellent conditions and resources for chemical evolution of peptides and proteins on the early earth. For valine, furthermore differences in catalytic yield increase are found indicating a chiral selectivity of the active copper complex of the reaction and showing a connection to previously found enantiomeric differences in complex formation constants with amino acids.

[Moderate exercise and intake of either high or low glycemic index carbohydrates in sedentary women].

PubMed

Ortiz-Rodríguez, Briseidy; De León, Lidia G; Esparza-Romero, Julián; Carrasco-Legleu, Claudia E; Candia-Luján, Ramón

2018-05-25

To analyze changes in blood glucose, insulin and triglyceride concentrations in relation to a moderate aerobic exercise in sedentary women of different body weight, exposed to either a high or low glycemic index carbohydrates diet. DISEñO: Cross-over type. SITE: Research was performed in the Exercise Physiology Laboratory at Facultad de Ciencias de la Cultura Física, Universidad Autónoma de Chihuahua, México. Twenty-six young sedentary women who did not exercise in the last year participated in the study. Four of adequate weight (AW) and 2 with obesity (OB) were excluded for not consuming the suggested carbohydrates (1gr/kg of weight) nor completed the programed exercise. There were n=10 in each group (AW/OB). Two treatments of 55minutes of aerobic exercise each were applied one day after consuming either high or low glycemic index carbohydrates. Plasmatic glucose, insulin, and triglycerides were determined before and after the scheduled exercise. Glucose, insulin, and triglycerides were higher in OB than in AW at baseline. Glucose was normalized in OB from 5.8±0.35 to 5.3±0.23 mmol/L (P=.001), only by eating foods with low glycemic index; triglycerides increased from 139.5±66.0 to 150.8±67.2mg/dl (P=.004) at the end of the exercise, after consumption of low glycemic index carbohydrates. Elevation of triglycerides secondary to exercise after consumption of low glycemic index seems to indicate an increase of lipid oxidation in OB. Copyright © 2018 The Authors. Publicado por Elsevier España, S.L.U. All rights reserved.

Fast characterization of solid organic waste content with near infrared spectroscopy in anaerobic digestion.

PubMed

Charnier, Cyrille; Latrille, Eric; Jimenez, Julie; Lemoine, Margaux; Boulet, Jean-Claude; Miroux, Jérémie; Steyer, Jean-Philippe

2017-01-01

The development of anaerobic digestion involves both co-digestion of solid wastes and optimization of the feeding recipe. Within this context, substrate characterisation is an essential issue. Although it is widely used, the biochemical methane potential is not sufficient to optimize the operation of anaerobic digestion plants. Indeed the biochemical composition in carbohydrates, lipids, proteins and the chemical oxygen demand of the inputs are key parameters for the optimisation of process performances. Here we used near infrared spectroscopy as a robust and less-time consuming tool to predict the solid waste content in carbohydrates, lipids and nitrogen, and the chemical oxygen demand. We built a Partial Least Square regression model with 295 samples and validated it with an independent set of 46 samples across a wide range of solid wastes found in anaerobic digestion units. The standard errors of cross-validation were 90mgO 2 ⋅gTS -1 carbohydrates, 2.5∗10 -2 g⋅gTS -1 lipids, 7.2∗10 -3 g⋅gTS -1 nitrogen and 99mgO 2 ⋅gTS -1 chemical oxygen demand. The standard errors of prediction were 53mgO 2 ⋅gTS -1 carbohydrates, 3.2∗10 -2 g⋅gTS -1 lipids, 8.6∗10 -3 g⋅gTS -1 nitrogen and 83mgO 2 ⋅gTS -1 chemical oxygen demand. These results show that near infrared spectroscopy is a new fast and cost-efficient way to characterize solid wastes content and improve their anaerobic digestion monitoring. Copyright © 2016 Elsevier Ltd. All rights reserved.

Carbohydrate Loading.

ERIC Educational Resources Information Center

Csernus, Marilyn

Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

Lignin and etherified ferulates impact digestibility and structural composition of three temperate perennial grasses

USDA-ARS?s Scientific Manuscript database

Breeding grasses for increased digestibility increases their value and profitability in ruminant livestock production systems. Digestibility can be improved in grasses by either increasing the concentration of soluble and readily fermentable carbohydrates or by altering the plant cell wall to create...

Low Carbohydrate and Moderately Fat-Reduced Diets Similarly Affected Early Weight Gain in Varenicline-Treated Overweight or Obese Smokers.

PubMed

Heggen, Eli; Svendsen, Mette; Klemsdal, Tor Ole; Tonstad, Serena

2016-06-01

Weight gain is common when stopping smoking. This study compared the effect of advising smokers to follow a diet low in carbohydrates versus a usual fat-reduced diet on weight gain and nicotine withdrawal. In a randomized clinical trial, 122 men and women smokers with body mass index 25-40kg/m(2) were assigned low-carbohydrate versus moderately fat-reduced diets. Within a week thereafter all participants started treatment with a 12-week course of varenicline 10 days prior to the target quit date. Brief dietary and motivational counseling was given at all visits. Self-reported abstinence was validated. Protein intake in the low-carbohydrate versus fat-reduced diets was 26.4% of total energy versus 20.0%, fat 38.2% versus 30.1%, and carbohydrates 29.0% versus 41.7% (all P < .001). Mean weight changes for the low-carbohydrate versus fat-reduced groups were -1.2 (SD 2.2) versus -0.5 (SD 2.0) kg, -0.2 (SD 3.3) versus 0.5 (SD 2.6) kg, and 2.2 (SD 4.5) versus 2.1 (SD 3.9) kg at 4, 12, and 24 weeks after the target quit date, respectively (not statistically significant). Smoking abstinence rates did not differ between diets. In the combined groups, point prevalence abstinence rates were 71.0% at 12 weeks and 46.3% at 24 weeks. The Minnesota Nicotine Withdrawal Symptoms score was lower in the fat-reduced group compared with the low-carbohydrate group at weeks 4 and 12. In overweight or obese smokers using varenicline a low-carbohydrate diet was no better than a fat-reduced diet in reducing weight gain but may result in more severe nicotine withdrawal symptoms. Compared to previous studies, cessation rates with varenicline were not impaired by dietary counseling. The study implies that a popular low-carbohydrate diet does not result in greater weight loss than a moderately fat-reduced diet in overweight and obese smokers who are attempting to quit smoking with the aid of varenicline. Dietary counseling combined with varenicline treatment did not appear to unfavorably

Cow, sheep and llama manure at psychrophilic anaerobic co-digestion with low cost tubular digesters in cold climate and high altitude.

PubMed

Martí-Herrero, J; Alvarez, R; Cespedes, R; Rojas, M R; Conde, V; Aliaga, L; Balboa, M; Danov, S

2015-04-01

The aim of this research is to evaluate the co-digestion of cow and llama manure combined with sheep manure, in psychrophilic conditions and real field low cost tubular digesters adapted to cold climate. Four digesters were monitored in cold climate conditions; one fed with cow manure, a second one with llama manure, the third one with co-digestion of cow-sheep manure and the fourth one was fed with llama-sheep manure. The slurry had a mean temperature of 16.6 °C, the organic load rate was 0.44 kgvs m(-3) d(-1) and the hydraulic retention time was 80 days. After one hundred days biogas production was stable, as was the methane content and the pH of the effluent. The co-digestion of cow-sheep manure results in a biogas production increase of 100% compared to the mono-digestion of cow manure, while co-digestion of llama-sheep manure results in a decrease of 50% in biogas production with respect to mono-digestion of llama manure. Copyright © 2015 Elsevier Ltd. All rights reserved.

Energy balance and hypothalamic effects of a high-protein/low-carbohydrate diet.

PubMed

Kinzig, Kimberly P; Hargrave, Sara L; Hyun, Jayson; Moran, Timothy H

2007-10-22

Diets high in fat or protein and extremely low in carbohydrate are frequently reported to result in weight loss in humans. We previously reported that rats maintained on a low-carbohydrate-high fat diet (LC-HF) consumed similar kcals/day as chow (CH)-fed rats and did not differ in body weight after 7 weeks. LC-HF rats had a 45% decrease in POMC expression in the ARC, decreased plasma insulin, and increased plasma leptin and ghrelin. In the present study we assessed the effects of a low-carbohydrate-high-protein diet (HP: 30% fat, 65% protein, and 5% CHO) on body weight, caloric intake, plasma hormone levels and hypothalamic gene expression. Male rats (n=16) were maintained on CH or HP for 4 weeks. HP rats gained significantly less weight than CH rats (73.4+/-9.4 and 125.0+/-8.2 g) and consumed significantly less kcals/day (94.8+/-1.5 and 123.6+/-1.1). Insulin was significantly reduced in HP rats (HP: 1.8+/-0.6 vs. CH: 4.12+/-0.8 ng/ml), there were no differences between groups in plasma leptin and plasma ghrelin was significantly elevated in HP rats (HP: 127.5+/-45 vs. CH: 76.9+/-8 pg/ml). Maintenance on HP resulted in significantly increased ARC POMC (HP: 121+/-10.0 vs. 100+/-5.9) and DMH NPY (HP: 297+/-82.1 vs. CH: 100+/-37.7) expression compared to CH controls. These data suggest that the macronutrient content of diets differentially influences hypothalamic gene expression in ways that can affect overall intake.

Digestive Enzyme Supplementation in Gastrointestinal Diseases.

PubMed

Ianiro, Gianluca; Pecere, Silvia; Giorgio, Valentina; Gasbarrini, Antonio; Cammarota, Giovanni

2016-01-01

Digestive enzymes are able to break down proteins and carbohydrates and lipids, and their supplementation may play a role in the management of digestive disorders, from lactose intolerance to cystic fibrosis. To date, several formulations of digestive enzymes are available on the market, being different each other in terms of enzyme type, source and origin, and dosage. This review, performed through a non-systematic search of the available literature, will provide an overview of the current knowledge of digestive enzyme supplementation in gastrointestinal disorders, discussion of the use of pancreatic enzymes, lactase (β-galactosidase) and conjugated bile acids, and also exploring the future perspective of digestive enzyme supplementation. Currently, the animal-derived enzymes represent an established standard of care, however the growing study of plant-based and microbe-derived enzymes offers great promise in the advancement of digestive enzyme therapy. New frontiers of enzyme replacement are being evaluated also in the treatment of diseases not specifically related to enzyme deficiency, whereas the combination of different enzymes might constitute an intriguing therapeutic option in the future.

Effect of digestible carbohydrates on glucose control in insulin-dependent diabetic patients.

PubMed

Perrotti, N; Santoro, D; Genovese, S; Giacco, A; Rivellese, A; Riccardi, G

1984-01-01

Recent studies have demonstrated that high-carbohydrate-high-fiber diets may improve the metabolic control in diabetes. To evaluate the influence of dietary carbohydrates separate from dietary fiber on blood glucose control, six insulin-dependent diabetic patients (IDD) were assigned in random order to two weight-maintaining diets for consecutive periods of 10 days. The diets differed in carbohydrate (41% in diet A and 60% in diet B) and fat content (41% and 20%, respectively) but were identical in calories, proteins, simple sugars, and fiber. After each dietary period blood glucose was continuously monitored for 24 h (Biostator GCIIS, Life Science Instruments, Miles Laboratories, Elkhart, Indiana). The M value was 48 +/- 20 after diet A and 96 +/- 27 after diet B (t = 3.83, P less than 0.025); the mean daily blood glucose was 152 +/- 5 mg/dl after diet A and 206 +/- 11 mg/dl after diet B (t = 7.50, P less than 0.001). Similarly, the blood glucose level for the 3-h period after each of the three main meals was lower after diet A than after diet B (analysis of variance: F = 5.2, P less than 0.05). No significant difference in fasting serum cholesterol, triglycerides, or serum lipoprotein composition was observed between the two diets. In order to separate the influence of dietary carbohydrate and fat on postprandial blood glucose concentration, an additional test meal experiment was performed in eight insulin-dependent diabetic patients. In random order on consecutive days they were given two standard meals that were identical in carbohydrate and protein content and differed only in the amount of olive oil added to the meals (12 g versus 36 g).(ABSTRACT TRUNCATED AT 250 WORDS)

Digestibility index and factors affecting rate of starch digestion in vitro in conventional food preparation.

PubMed

Urooj, A; Puttraj, S

1999-02-01

The rate of starch hydrolysis in ten cereal-based food preparations was studied using an in vitro dialysis system. The foods were incubated with human saliva and porcine pancreatin. The sugars released after 3 h digestion were expressed as digestibility index (DI), the percentage starch digested was determined and correlated with the degree of gelatinization (DG). Granule morphology was also investigated and related with starch availability for hydrolysis. Significant differences were observed in the in vitro starch digestibility of the 10 foods (P < 0.05). The DI ranged from 53 for chapathi to 78 for rice flakes. DI was inversely related to the protein (r = -0.79, P < 0.01), fat (r = -0.63, P < 0.05) and energy (r = -0.61, P < 0.01). Percent starch digested was inversely related to the insoluble (r = -0.49, P < 0.05) and total dietary fiber (r = -0.63, P < 0.01) content of the foods. The SEM results provided a better understanding of granular morphology on cooking and the effect of protein on limiting DG. The results suggest that carbohydrate foods of potential use in the therapeutic diets may be identified by their in vitro digestion characteristics.

Quantification of fructans, galacto-oligosacharides and other short-chain carbohydrates in processed grains and cereals.

PubMed

Biesiekierski, J R; Rosella, O; Rose, R; Liels, K; Barrett, J S; Shepherd, S J; Gibson, P R; Muir, J G

2011-04-01

Wholegrain grains and cereals contain a wide range of potentially protective factors that are relevant to gastrointestinal health. The prebiotics best studied are fructans [fructooligosaccharides (FOS), inulin] and galactooligosaccharides (GOS). These and other short-chain carbohydrates can also be poorly absorbed in the small intestine (named fermentable oligo-, di- and monosaccharides and polyols; FODMAPs) and may have important implications for the health of the gut. In the present study, FODMAPs, including fructose in excess of glucose, FOS (nystose, kestose), GOS (raffinose, stachyose) and sugar polyols (sorbitol, mannitol), were quantified using high-performance liquid chromatography with an evaporative light scattering detector. Total fructan was quantified using an enzymic hydrolysis method. Fifty-five commonly consumed grains, breakfast cereals, breads, pulses and biscuits were analysed. Total fructan were the most common short-chain carbohydrate present in cereal grain products and ranged (g per portion as eaten) from 1.12 g in couscous to 0 g in rice; 0.6 g in dark rye bread to 0.07 g in spelt bread; 0.96 g in wheat-free muesli to 0.11 g in oats; and 0.81 g in muesli fruit bar to 0.05 g in potato chips. Raffinose and stachyose were most common in pulses.   Composition tables including FODMAPs and prebiotics (FOS and GOS) that are naturally present in food will greatly assist research aimed at understanding their physiological role in the gut. © 2011 The Authors. Journal compilation © 2011 The British Dietetic Association Ltd.

Effects of freezing, freeze drying and convective drying on in vitro gastric digestion of apples.

PubMed

Dalmau, Maria Esperanza; Bornhorst, Gail M; Eim, Valeria; Rosselló, Carmen; Simal, Susana

2017-01-15

The influence of processing (freezing at -196°C in liquid N2, FN sample; freeze-drying at -50°C and 30Pa, FD sample; and convective drying at 60°C and 2m/s, CD sample) on apple (var. Granny Smith) behavior during in vitro gastric digestion was investigated. Dried apples (FD and CD samples) were rehydrated prior to digestion. Changes in carbohydrate composition, moisture, soluble solids, acidity, total polyphenol content (TPC), and antioxidant activity (AA) of apple samples were measured at different times during digestion. Processing resulted in disruption of the cellular structure during digestion, as observed by scanning electron microscopy, light microscopy, and changes in carbohydrate composition. Moisture content increased (6-11% dmo), while soluble solids (55-78% dmo), acidity (44-72% dmo), total polyphenol content (30-61% dmo), and antioxidant activity (41-87%) decreased in all samples after digestion. Mathematical models (Weibull and exponential models) were used to better evaluate the influence of processing on apple behavior during gastric digestion. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Effect of Low Carbohydrate Diets on Fertility Hormones and Outcomes in Overweight and Obese Women: A Systematic Review

PubMed Central

McGrice, Melanie; Porter, Judi

2017-01-01

(1) Background: Medical interventions including assisted reproductive technologies have improved fertility outcomes for many sub-fertile couples. Increasing research interest has investigated the effect of low carbohydrate diets, with or without energy restriction. We aimed to systematically review the published literature to determine the extent to which low carbohydrate diets can affect fertility outcomes; (2) Methods: The review protocol was registered prospectively with Prospective Register for Systematic Reviews (registration number CRD42016042669) and followed Preferred Reporting Items For Systematic Reviews and Meta-Analyses guidelines. Infertile women were the population of interest, the intervention was low carbohydrate diets (less than 45% total energy from carbohydrates), compared to usual diet (with or without co-treatments). Four databases were searched from date of commencement until April 2016; a supplementary Google scholar search was also undertaken. Title and abstract, then full text review, were undertaken independently and in duplicate. Reference lists of included studies and relevant systematic reviews were checked to ensure that all relevant studies were identified for inclusion. Quality assessment was undertaken independently by both authors using the Quality Criteria Checklist for Primary Research. Outcome measures were improved fertility outcomes defined by an improvement in reproductive hormones, ovulation rates and/or pregnancy rates; (3) Results: Seven studies fulfilled the inclusion criteria and were included in the evidence synthesis. Interventions were diverse and included a combination of low carbohydrate diets with energy deficit or other co-treatments. Study quality was rated as positive for six studies, suggesting a low risk of bias, with one study rated as neutral. Of the six studies which reported changes in reproductive hormones, five reported significant improvements post intervention; (4) Conclusion: The findings of these

Effects of dietary carbohydrate restriction versus low-fat diet on flow-mediated dilation.

PubMed

Volek, Jeff S; Ballard, Kevin D; Silvestre, Ricardo; Judelson, Daniel A; Quann, Erin E; Forsythe, Cassandra E; Fernandez, Maria Luz; Kraemer, William J

2009-12-01

We previously reported that a carbohydrate-restricted diet (CRD) ameliorated many of the traditional markers associated with metabolic syndrome and cardiovascular risk compared with a low-fat diet (LFD). There remains concern how CRD affects vascular function because acute meals high in fat have been shown to impair endothelial function. Here, we extend our work and address these concerns by measuring fasting and postprandial vascular function in 40 overweight men and women with moderate hypertriacylglycerolemia who were randomly assigned to consume hypocaloric diets (approximately 1500 kcal) restricted in carbohydrate (percentage of carbohydrate-fat-protein = 12:59:28) or LFD (56:24:20). Flow-mediated dilation of the brachial artery was assessed before and after ingestion of a high-fat meal (908 kcal, 84% fat) at baseline and after 12 weeks. Compared with the LFD, the CRD resulted in a greater decrease in postprandial triacylglycerol (-47% vs -15%, P = .007), insulin (-51% vs -6%, P = .009), and lymphocyte (-12% vs -1%, P = .050) responses. Postprandial fatty acids were significantly increased by the CRD compared with the LFD (P = .033). Serum interleukin-6 increased significantly over the postprandial period; and the response was augmented in the CRD (46%) compared with the LFD (-13%) group (P = .038). After 12 weeks, peak flow-mediated dilation at 3 hours increased from 5.1% to 6.5% in the CRD group and decreased from 7.9% to 5.2% in the LFD group (P = .004). These findings show that a 12-week low-carbohydrate diet improves postprandial vascular function more than a LFD in individuals with atherogenic dyslipidemia.

Effects of short-term very low-carbohydrate or conventional diet on strength performance.

PubMed

Meirelles, C; Candido, T; Gomes, P S

2010-06-01

Weight reduction strategies usually include diet and regular physical activity. A very low-carbohydrate and high protein diet (VLCD) may be preferred instead of a low energy conventional diet (CONV). The effects of VLCD on strength performance are yet to be understood. Aim of the study is to determine the effects of two different restrictive diets on strength performance. Sedentary women were assigned to either a VLCD (<40 g carbohydrate; n=12) or a CONV diet (500 to 800 kcal restrictive; 48%, 22% and 30% from carbohydrate, protein and fat, respectively; n=12). Knee extension isokinetic strength tests (3 yen 15 reps at 60 degrees .s-1, with 90 or 180 s rest interval between sets) were performed prior and after a one week diet period. Both groups reduced body mass (VLCD: -2.6+/-1.0% vs. CONV: -1.9+/-1.3%; P<0.05), with no between diets effect. The sum of the total work in three sets (ATW) was 4850+/-1002 J vs. 4801+/-973 J with 90 s rest interval, and 4812+/-1174 J vs. 4812+/-1210 J with 180 s rest interval, respectively, in the pre vs. post-VLCD period. For CONV, values were 4709+/-729 J vs. 4530+/-996 J with 90 s rest interval, and 4760+/-732 J vs. 4816+/-702 J with 180 s rest interval, respectively, in the pre vs. post-CONV treatment. No significant differences were detected in the ATW between groups. Short-term hypoenergetic diets, irrespective of the carbohydrate content, seem to reduce significantly body mass, but do not impair acute strength performance.

Prebiotics, probiotics, and synbiotics affect mineral absorption, bone mineral content, and bone structure.

PubMed

Scholz-Ahrens, Katharina E; Ade, Peter; Marten, Berit; Weber, Petra; Timm, Wolfram; Açil, Yahya; Glüer, Claus-C; Schrezenmeir, Jürgen

2007-03-01

Several studies in animals and humans have shown positive effects of nondigestible oligosaccharides (NDO) on mineral absorption and metabolism and bone composition and architecture. These include inulin, oligofructose, fructooligosaccharides, galactooligosaccharides, soybean oligosaccharide, and also resistant starches, sugar alcohols, and difructose anhydride. A positive outcome of dietary prebiotics is promoted by a high dietary calcium content up to a threshold level and an optimum amount and composition of supplemented prebiotics. There might be an optimum composition of fructooligosaccharides with different chain lengths (synergy products). The efficacy of dietary prebiotics depends on chronological age, physiological age, menopausal status, and calcium absorption capacity. There is evidence for an independent probiotic effect on facilitating mineral absorption. Synbiotics, i.e., a combination of probiotics and prebiotics, can induce additional effects. Whether a low content of habitual NDO would augment the effect of dietary prebiotics or synbiotics remains to be studied. The underlying mechanisms are manifold: increased solubility of minerals because of increased bacterial production of short-chain fatty acids, which is promoted by the greater supply of substrate; an enlargement of the absorption surface by promoting proliferation of enterocytes mediated by bacterial fermentation products, predominantly lactate and butyrate; increased expression of calcium-binding proteins; improvement of gut health; degradation of mineral complexing phytic acid; release of bone-modulating factors such as phytoestrogens from foods; stabilization of the intestinal flora and ecology, also in the presence of antibiotics; stabilization of the intestinal mucus; and impact of modulating growth factors such as polyamines. In conclusion, prebiotics are the most promising but also best investigated substances with respect to a bone-health-promoting potential, compared with probiotics

Hepatic steatosis, inflammation, and ER stress in mice maintained long term on a very low-carbohydrate ketogenic diet

PubMed Central

Garbow, Joel R.; Doherty, Jason M.; Schugar, Rebecca C.; Travers, Sarah; Weber, Mary L.; Wentz, Anna E.; Ezenwajiaku, Nkiruka; Cotter, David G.; Brunt, Elizabeth M.

2011-01-01

Low-carbohydrate diets are used to manage obesity, seizure disorders, and malignancies of the central nervous system. These diets create a distinctive, but incompletely defined, cellular, molecular, and integrated metabolic state. Here, we determine the systemic and hepatic effects of long-term administration of a very low-carbohydrate, low-protein, and high-fat ketogenic diet, serially comparing these effects to a high-simple-carbohydrate, high-fat Western diet and a low-fat, polysaccharide-rich control chow diet in C57BL/6J mice. Longitudinal measurement of body composition, serum metabolites, and intrahepatic fat content, using in vivo magnetic resonance spectroscopy, reveals that mice fed the ketogenic diet over 12 wk remain lean, euglycemic, and hypoinsulinemic but accumulate hepatic lipid in a temporal pattern very distinct from animals fed the Western diet. Ketogenic diet-fed mice ultimately develop systemic glucose intolerance, hepatic endoplasmic reticulum stress, steatosis, cellular injury, and macrophage accumulation, but surprisingly insulin-induced hepatic Akt phosphorylation and whole-body insulin responsiveness are not impaired. Moreover, whereas hepatic Pparg mRNA abundance is augmented by both high-fat diets, each diet confers splice variant specificity. The distinctive nutrient milieu created by long-term administration of this low-carbohydrate, low-protein ketogenic diet in mice evokes unique signatures of nonalcoholic fatty liver disease and whole-body glucose homeostasis. PMID:21454445

Effect of a 6-month vegan low-carbohydrate ('Eco-Atkins') diet on cardiovascular risk factors and body weight in hyperlipidaemic adults: a randomised controlled trial.

PubMed

Jenkins, David J A; Wong, Julia M W; Kendall, Cyril W C; Esfahani, Amin; Ng, Vivian W Y; Leong, Tracy C K; Faulkner, Dorothea A; Vidgen, Ed; Paul, Gregory; Mukherjea, Ratna; Krul, Elaine S; Singer, William

2014-02-05

Low-carbohydrate diets may be useful for weight loss. Diets high in vegetable proteins and oils may reduce the risk of coronary heart disease. The main objective was to determine the longer term effect of a diet that was both low-carbohydrate and plant-based on weight loss and low-density lipoprotein cholesterol (LDL-C). A parallel design study of 39 overweight hyperlipidaemic men and postmenopausal women conducted at a Canadian university-affiliated hospital nutrition research centre from April 2005 to November 2006. Participants were advised to consume either a low-carbohydrate vegan diet or a high-carbohydrate lacto-ovo vegetarian diet for 6 months after completing 1-month metabolic (all foods provided) versions of these diets. The prescribed macronutrient intakes for the low-carbohydrate and high-carbohydrate diets were: 26% and 58% of energy from carbohydrate, 31% and 16% from protein and 43% and 25% from fat, respectively. Change in body weight. 23 participants (50% test, 68% control) completed the 6-month ad libitum study. The approximate 4 kg weight loss on the metabolic study was increased to -6.9 kg on low-carbohydrate and -5.8 kg on high-carbohydrate 6-month ad libitum treatments (treatment difference (95% CI) -1.1 kg (-2.1 to 0.0), p=0.047). The relative LDL-C and triglyceride reductions were also greater on the low-carbohydrate treatment (treatment difference (95% CI) -0.49 mmol/L (-0.70 to -0.28), p<0.001 and -0.34 mmol/L (-0.57 to -0.11), p=0.005, respectively), as were the total cholesterol:HDL-C and apolipoprotein B:A1 ratios (-0.57 (-0.83, -0.32), p<0.001 and -0.05 (-0.09, -0.02), p=0.003, respectively). A self-selected low-carbohydrate vegan diet, containing increased protein and fat from gluten and soy products, nuts and vegetable oils, had lipid lowering advantages over a high-carbohydrate, low-fat weight loss diet, thus improving heart disease risk factors. clinicaltrials.gov (http://www.clinicaltrials.gov/), #NCT00256516.

Prebiotic Supplementation has Only Minimal Effects on Growth Efficiency, Intestinal Health and Disease Resistance of Westslope Cutthroat Trout Oncorhynchus clarkii lewisi Fed 30% Soybean Meal

PubMed Central

Sealey, Wendy M.; Conley, Zachariah B.; Bensley, Molly

2015-01-01

Prebiotics have successfully been used to prevent infectious diseases in aquaculture and there is an increasing amount of literature that suggests that these products can also improve alternative protein utilization and digestion. Therefore, the objective of this study was to examine whether prebiotic supplementation increased the growth efficiency, intestinal health, and disease resistance of cutthroat trout fed a high level of dietary soybean meal. To achieve this objective, juvenile Westslope cutthroat trout (Oncorhynchus clarkii lewisi) were fed a practical type formulation with 0 or 30% dietary soybean meal with or without the commercial prebiotic (Grobiotic-A) prior to experimental exposure to Flavobacterium psychrophilum. Juvenile Westslope cutthroat trout (initial weight 7.8 g/fish ±SD of 0.5 g) were stocked at 30 fish/tank in 75 L tanks with six replicate tanks per diet and fed their respective diets for 20 weeks. Final weights of Westslope cutthroat trout were affected by neither dietary soybean meal inclusion level (P = 0.9582) nor prebiotic inclusion (P = 0.9348) and no interaction was observed (P = 0.1242). Feed conversion ratios were similarly not affected by soybean meal level (P = 0.4895), prebiotic inclusion (P = 0.3258) or their interaction (P = 0.1478). Histological examination of the distal intestine of Westslope cutthroat trout demonstrated increases in inflammation due to both increased soybean meal inclusion level (P = 0.0038) and prebiotic inclusion (P = 0.0327) without significant interaction (P = 0.3370). Feeding dietary soybean meal level at 30% increased mortality of F. psychrophilum cohabitation challenged Westslope cutthroat trout (P = 0.0345) while prebiotic inclusion tended to decrease mortality (P = 0.0671). These results indicate that subclinical alterations in intestinal inflammation levels due to high dietary inclusion levels of soybean meal could predispose Westslope cutthroat

Ruminant Nutrition Symposium: Productivity, digestion, and health responses to hindgut acidosis in ruminants.

PubMed

Gressley, T F; Hall, M B; Armentano, L E

2011-04-01

Microbial fermentation of carbohydrates in the hindgut of dairy cattle is responsible for 5 to 10% of total-tract carbohydrate digestion. When dietary, animal, or environmental factors contribute to abnormal, excessive flow of fermentable carbohydrates from the small intestine, hindgut acidosis can occur. Hindgut acidosis is characterized by increased rates of production of short-chain fatty acids including lactic acid, decreased digesta pH, and damage to gut epithelium as evidenced by the appearance of mucin casts in feces. Hindgut acidosis is more likely to occur in high-producing animals fed diets with relatively greater proportions of grains and lesser proportions of forage. In these animals, ruminal acidosis and poor selective retention of fermentable carbohydrates by the rumen will increase carbohydrate flow to the hindgut. In more severe situations, hindgut acidosis is characterized by an inflammatory response; the resulting breach of the barrier between animal and digesta may contribute to laminitis and other disorders. In a research setting, effects of increased hindgut fermentation have been evaluated using pulse-dose or continuous abomasal infusions of varying amounts of fermentable carbohydrates. Continuous small-dose abomasal infusions of 1 kg/d of pectin or fructans into lactating cows resulted in decreased diet digestibility and decreased milk fat percentage without affecting fecal pH or VFA concentrations. The decreased diet digestibility likely resulted from increased bulk in the digestive tract or from increased digesta passage rate, reducing exposure of the digesta to intestinal enzymes and epithelial absorptive surfaces. The same mechanism is proposed to explain the decreased milk fat percentage because only milk concentrations of long-chain fatty acids were decreased. Pulse-dose abomasal fructan infusions (1 g/kg of BW) into steers resulted in watery feces, decreased fecal pH, and increased fecal VFA concentrations, without causing an

In vitro fermentation and prebiotic potential of novel low molecular weight polysaccharides derived from agar and alginate seaweeds.

PubMed

Ramnani, Priya; Chitarrari, Roberto; Tuohy, Kieran; Grant, John; Hotchkiss, Sarah; Philp, Kevin; Campbell, Ross; Gill, Chris; Rowland, Ian

2012-02-01

Fermentation properties and prebiotic potential of novel low molecular weight polysaccharides (LMWPs) derived from agar and alginate bearing seaweeds was investigated. Ten LMWPs were supplemented to pH, temperature controlled anaerobic batch cultures inoculated with human feces from three donors, in triplicate. Microbiota changes were monitored using Fluorescent in-situ hybridization and short chain fatty acids, the fermentation end products were analysed using gas chromatography. Of the ten LMWPs tested, Gelidium seaweed CC2253 of molecular weight 64.64 KDa showed a significant increase in bifidobacterial populations from log(10) 8.06 at 0 h to log(10) 8.55 at 24 h (p = 0.018). For total bacterial populations, alginate powder CC2238 produced a significant increase from log(10) 9.01 at 0 h to log(10) 9.58 at 24 h (p = 0.032). No changes were observed in the other bacterial groups tested viz. Bacteroides, Lactobacilli/Enterococci, Eubacterium rectale/Clostridium coccoides and Clostridium histolyticum. The polysaccharides also showed significant increases in total SCFA production, particularly acetic and propionic acids, indicating that they were readily fermented. In conclusion, some LMWPs derived from agar and alginate bearing seaweeds were fermented by gut bacteria and exhibited potential to be used a novel source of prebiotics. Copyright © 2011 Elsevier Ltd. All rights reserved.

Small-bowel absorption of D-tagatose and related effects on carbohydrate digestibility: an ileostomy study.

PubMed

Normén, L; Laerke, H N; Jensen, B B; Langkilde, A M; Andersson, H

2001-01-01

The ketohexose D-tagatose is a new sweetener with a low energy content. This low energy content may be due to either low absorption of the D-tagatose or decreased absorption of other nutrients. The aims of this study were to measure the excretion of D-tagatose from the human small bowel, to calculate the apparent absorption of D-tagatose, and to study the effects of D-tagatose on the small-bowel excretion of other carbohydrates. A controlled diet was served for 2 periods of 2 d during 3 consecutive weeks to 6 ileostomy subjects. In one of the periods, 15 g D-tagatose was added to the diet daily. Duplicate portions of the diet and ileostomy effluents were freeze-dried and analyzed to calculate the apparent net absorption of D-tagatose and carbohydrates. Median D-tagatose excretion was 19% (range: 12-31%), which corresponded to a calculated apparent absorption of 81% (69-88%). Of the total amount of D-tagatose excreted [2.8 g (1.7-4.4 g)], 60% (8-88%) was excreted within 3 h. Between 3 and 5 h, 32% (11-82%) was excreted. Excretion of wet matter increased by 41% (24-52%) with D-tagatose ingestion. Sucrose and D-glucose excretion increased to a small extent, whereas no significant changes were found in the excretion of dry matter, energy, starch, or D-fructose. The apparent absorption of 15 g D-tagatose/d was 81%. D-Tagatose had only a minor influence on the apparent absorption of other nutrients.

A Metagenomics Investigation of Carbohydrate-Active Enzymes along the Gastrointestinal Tract of Saudi Sheep.

PubMed

Al-Masaudi, Saad; El Kaoutari, Abdessamad; Drula, Elodie; Al-Mehdar, Hussein; Redwan, Elrashdy M; Lombard, Vincent; Henrissat, Bernard

2017-01-01

The digestive microbiota of humans and of a wide range of animals has recently become amenable to in-depth studies due to the emergence of DNA-based metagenomic techniques that do not require cultivation of gut microbes. These techniques are now commonly used to explore the feces of humans and animals under the assumption that such samples are faithful proxies for the intestinal microbiota. Sheep ( Ovis aries ) are ruminant animals particularly adapted to life in arid regions and in particular Najdi, Noaimi (Awassi), and Harrei (Harri) breeds that are raised in Saudi Arabia for milk and/or meat production. Here we report a metagenomics investigation of the distal digestive tract of one animal from each breed that (i) examines the microbiota at three intestinal subsites (small intestine, mid-colon, and rectum), (ii) performs an in-depth analysis of the carbohydrate-active enzymes genes encoded by the microbiota at the three subsites, and (iii) compares the microbiota and carbohydrate-active enzyme profile at the three subsites across the different breeds. For all animals we found that the small intestine is characterized by a lower taxonomic diversity than that of the large intestine and of the rectal samples. Mirroring this observation, we also find that the spectrum of encoded carbohydrate-active enzymes of the mid-colon and rectal sites is much richer than that of the small intestine. However, the number of encoded cellulases and xylanases in the various intestinal subsites was found to be surprisingly low, indicating that the bulk of the fiber digestion is performed upstream in the rumen, and that the carbon source for the intestinal flora is probably constituted of the rumen fungi and bacteria that pass in the intestines. In consequence we argue that ruminant feces, which are often analyzed for the search of microbial genes involved in plant cell wall degradation, are probably a poor proxy for the lignocellulolytic potential of the host.

Comparison of a low carbohydrate and low fat diet for weight maintenance in overweight or obese adults enrolled in a clinical weight management program

PubMed Central

LeCheminant, James D; Gibson, Cheryl A; Sullivan, Debra K; Hall, Sandra; Washburn, Rik; Vernon, Mary C; Curry, Chelsea; Stewart, Elizabeth; Westman, Eric C; Donnelly, Joseph E

2007-01-01

Background Recent evidence suggests that a low carbohydrate (LC) diet may be equally or more effective for short-term weight loss than a traditional low fat (LF) diet; however, less is known about how they compare for weight maintenance. The purpose of this study was to compare body weight (BW) for participants in a clinical weight management program, consuming a LC or LF weight maintenance diet for 6 months following weight loss. Methods Fifty-five (29 low carbohydrate diet; 26 low fat diet) overweight/obese middle-aged adults completed a 9 month weight management program that included instruction for behavior, physical activity (PA), and nutrition. For 3 months all participants consumed an identical liquid diet (2177 kJ/day) followed by 1 month of re-feeding with solid foods either low in carbohydrate or low in fat. For the remaining 5 months, participants were prescribed a meal plan low in dietary carbohydrate (~20%) or fat (~30%). BW and carbohydrate or fat grams were collected at each group meeting. Energy and macronutrient intake were assessed at baseline, 3, 6, and 9 months. Results The LC group increased BW from 89.2 ± 14.4 kg at 3 months to 89.3 ± 16.1 kg at 9 months (P = 0.84). The LF group decreased BW from 86.3 ± 12.0 kg at 3 months to 86.0 ± 14.0 kg at 9 months (P = 0.96). BW was not different between groups during weight maintenance (P = 0.87). Fifty-five percent (16/29) and 50% (13/26) of participants for the LC and LF groups, respectively, continued to decrease their body weight during weight maintenance. Conclusion Following a 3 month liquid diet, the LC and LF diet groups were equally effective for BW maintenance over 6 months; however, there was significant variation in weight change within each group. PMID:17976244

Evaluation of the National Research Council (2001) dairy model and derivation of new prediction equations. 1. Digestibility of fiber, fat, protein, and nonfiber carbohydrate.

PubMed

White, R R; Roman-Garcia, Y; Firkins, J L; VandeHaar, M J; Armentano, L E; Weiss, W P; McGill, T; Garnett, R; Hanigan, M D

2017-05-01

Evaluation of ration balancing systems such as the National Research Council (NRC) Nutrient Requirements series is important for improving predictions of animal nutrient requirements and advancing feeding strategies. This work used a literature data set (n = 550) to evaluate predictions of total-tract digested neutral detergent fiber (NDF), fatty acid (FA), crude protein (CP), and nonfiber carbohydrate (NFC) estimated by the NRC (2001) dairy model. Mean biases suggested that the NRC (2001) lactating cow model overestimated true FA and CP digestibility by 26 and 7%, respectively, and under-predicted NDF digestibility by 16%. All NRC (2001) estimates had notable mean and slope biases and large root mean squared prediction error (RMSPE), and concordance (CCC) ranged from poor to good. Predicting NDF digestibility with independent equations for legumes, corn silage, other forages, and nonforage feeds improved CCC (0.85 vs. 0.76) compared with the re-derived NRC (2001) equation form (NRC equation with parameter estimates re-derived against this data set). Separate FA digestion coefficients were derived for different fat supplements (animal fats, oils, and other fat types) and for the basal diet. This equation returned improved (from 0.76 to 0.94) CCC compared with the re-derived NRC (2001) equation form. Unique CP digestibility equations were derived for forages, animal protein feeds, plant protein feeds, and other feeds, which improved CCC compared with the re-derived NRC (2001) equation form (0.74 to 0.85). New NFC digestibility coefficients were derived for grain-specific starch digestibilities, with residual organic matter assumed to be 98% digestible. A Monte Carlo cross-validation was performed to evaluate repeatability of model fit. In this procedure, data were randomly subsetted 500 times into derivation (60%) and evaluation (40%) data sets, and equations were derived using the derivation data and then evaluated against the independent evaluation data. Models

A very low-carbohydrate, low-saturated fat diet for type 2 diabetes management: a randomized trial.

PubMed

Tay, Jeannie; Luscombe-Marsh, Natalie D; Thompson, Campbell H; Noakes, Manny; Buckley, Jon D; Wittert, Gary A; Yancy, William S; Brinkworth, Grant D

2014-11-01

To comprehensively compare the effects of a very low-carbohydrate, high-unsaturated/low-saturated fat diet (LC) with those of a high-unrefined carbohydrate, low-fat diet (HC) on glycemic control and cardiovascular disease (CVD) risk factors in type 2 diabetes (T2DM). Obese adults (n = 115, BMI 34.4 ± 4.2 kg/m(2), age 58 ± 7 years) with T2DM were randomized to a hypocaloric LC diet (14% carbohydrate [<50 g/day], 28% protein, and 58% fat [<10% saturated fat]) or an energy-matched HC diet (53% carbohydrate, 17% protein, and 30% fat [<10% saturated fat]) combined with structured exercise for 24 weeks. The outcomes measured were as follows: glycosylated hemoglobin (HbA1c), glycemic variability (GV; assessed by 48-h continuous glucose monitoring), antiglycemic medication changes (antiglycemic medication effects score [MES]), and blood lipids and pressure. A total of 93 participants completed 24 weeks. Both groups achieved similar completion rates (LC 79%, HC 82%) and weight loss (LC -12.0 ± 6.3 kg, HC -11.5 ± 5.5 kg); P ≥ 0.50. Blood pressure (-9.8/-7.3 ± 11.6/6.8 mmHg), fasting blood glucose (-1.4 ± 2.3 mmol/L), and LDL cholesterol (-0.3 ± 0.6 mmol/L) decreased, with no diet effect (P ≥ 0.10). LC achieved greater reductions in triglycerides (-0.5 ± 0.5 vs. -0.1 ± 0.5 mmol/L), MES (-0.5 ± 0.5 vs. -0.2 ± 0.5), and GV indices; P ≤ 0.03. LC induced greater HbA1c reductions (-2.6 ± 1.0% [-28.4 ± 10.9 mmol/mol] vs. -1.9 ± 1.2% [-20.8 ± 13.1 mmol/mol]; P = 0.002) and HDL cholesterol (HDL-C) increases (0.2 ± 0.3 vs. 0.05 ± 0.2 mmol/L; P = 0.007) in participants with the respective baseline values HbA1c >7.8% (62 mmol/mol) and HDL-C <1.29 mmol/L. Both diets achieved substantial improvements for several clinical glycemic control and CVD risk markers. These improvements and reductions in GV and antiglycemic medication requirements were greatest with the LC compared with HC. This suggests an LC diet with low saturated fat may be an effective dietary approach

Thermodynamic Basis for the Emergence of Genomes during Prebiotic Evolution

DTIC Science & Technology

2012-05-01

Thermodynamic Basis for the Emergence of Genomes during Prebiotic Evolution Hyung-June Woo, Ravi Vijaya Satya, Jaques Reifman* DoD Biotechnology High...polymerases are above, near, and below a critical point, respectively. The prebiotic evolution therefore must have crossed this critical region. Over...among many potential oligomers capable of templated replication, RNAs may have evolved to form prebiotic genomes due to the value of their nonenzymatic

Antibiotics, probiotics and prebiotics in IBD.

PubMed

Bernstein, Charles N

2014-01-01

The dysbiosis theory of inflammatory bowel disease (IBD) posits that there is an alteration in the gut microbiome as an important underpinning of disease etiology. It stands to reason then, that administering agents that could impact on the balance of microbes on the gut could be impactful on the course of IBD. Herein is a review of the controlled trials undertaken to assess the use of antibiotics that would kill or suppress potentially injurious microbes, probiotics that would overpopulate the gut with potentially beneficial microbes or prebiotics that provide a metabolic substrate that enhances the growth of potentially beneficial microbes. With regard to antibiotics, the best data are for the use of nitroimadoles postoperatively in Crohn's disease (CD) to prevent disease recurrence. Otherwise, the data are limited with the regard to any lasting benefit of antibiotics sustaining remission in either CD or ulcerative colitis (UC). A recent meta-analysis concluded that antibiotics are superior to placebo at inducing remission in CD or UC, although the meta-analysis grouped a variety of antibiotics with different spectra of activity. Despite the absence of robust clinical trial data, antibiotics are widely used to treat perineal fistulizing CD and acute and chronic pouchitis. Probiotics have not been shown to have a beneficial role in CD. However, Escherichia coli Nissle 1917 has comparable effects to low doses of mesalamine in maintaining remission in UC. VSL#3, a combination of 8 microbes, has been shown to have an effect in inducing remission in UC and preventing pouchitis. Prebiotics have yet to be shown to have an effect in any form of IBD, but to date controlled trials have been small. The use of antibiotics should be balanced against the risks they pose. Even probiotics may pose some risk and should not be assumed to be innocuous especially when ingested by persons with a compromised epithelial barrier. Prebiotics may not be harmful but may cause

Initialization of metabolism in prebiotic petroleum

NASA Astrophysics Data System (ADS)

Mekki-Berrada, Ali

The theoretical and bibliographical work on the geochemical origin of life, which I present here, it works on the assumption that: "The class of more complex molecules of life that can have a geochemical and abiotic origin is the class of fatty acid with long aliphatic chain". This idea comes from the controversy over the abiotic oil industry, and the first measurements of abiotic oil at mid-ocean ridges (Charlou J.L. et al. 2002, Proskurowski G. et al. 2008). To go further and propose a comprehensive experimentation on the origin of life, I propose in this article the idea that the prebiotic soup or prebiotic petroleum would stem from the diagenesis of the gas clathrates/sediments mixture. Gas, H2S H2 N2 CH4 CO2, are produced at mid-ocean ridges, and at large-scale at the seafloor, by serpentinization. Sediments contain hydrogenophosphates as a source of phosphate and minerals to the surface catalysis. Extreme conditions experienced by some prokaryotes and pressures and temperatures of submarine oilfields of fossil petroleum are close. The hydrostatic pressure is around 1.5 kbar and the temperature is below 150 °C. This experiment I propose is quite feasible today since these conditions are used: In research and exploration of fossil petroleum; In the field of organic chemistry called "green chemistry" and where temperatures remain low and the pressure can reach 10 kbar; to study the biology of prokaryotes living in the fossil petroleum of industrial interest, these studies are quite comparable to experiment with prebiotic oil; Finally, this experiment can be based on research on abiotic CH4 on Mars and abiotic hydrocarbons on Titan. The next step in the theoretical research of the origin of life is the abiotic synthesis of liposomes. Abiotic synthesis liposomes just requires synthesis of glycerol and ethanolamine (or serine) esterifying the phosphate and fatty acid. The state of research on the abiotic synthesis of these molecules shows that synthesis of

Intake of High-Fat Yogurt, but Not of Low-Fat Yogurt or Prebiotics, Is Related to Lower Risk of Depression in Women of the SUN Cohort Study.

PubMed

Perez-Cornago, Aurora; Sanchez-Villegas, Almudena; Bes-Rastrollo, Maira; Gea, Alfredo; Molero, Patricio; Lahortiga-Ramos, Francisca; Martínez-González, Miguel Angel

2016-09-01

Yogurt and prebiotic consumption has been linked to better health. However, to our knowledge, no longitudinal study has assessed the association of yogurt and prebiotic consumption with depression risk. We longitudinally evaluated the association of yogurt and prebiotic consumption with depression risk in a Mediterranean cohort. The SUN (Seguimiento Universidad de Navarra) Project is a dynamic, prospective cohort of Spanish university graduates. A total of 14,539 men and women (mean age: 37 y) initially free of depression were assessed during a median follow-up period of 9.3 y. Validated food-frequency questionnaires at baseline and after a 10-y follow-up were used to assess prebiotic (fructans and galacto-oligosaccharide) intake and yogurt consumption (<0.5, ≥0.5 to <3, ≥3 to <7, and ≥7 servings/wk). Participants were classified as incident cases of depression when they reported a new clinical diagnosis of depression by a physician (previously validated). Multivariable Cox proportional hazards models were used to calculate HRs and 95% CIs. We identified 727 incident cases of depression during follow-up. Whole-fat yogurt intake was associated with reduced depression risk: HR for the highest [≥7 servings/wk (1 serving = 125 g)] compared with the lowest (<0.5 servings/wk) consumption: 0.78 (95% CI: 0.63, 0.98; P-trend = 0.020). When stratified by sex, this association was significant only in women (HR: 0.66; 95% CI: 0.50, 0.87; P-trend = 0.004). Low-fat yogurt consumption was associated with a higher incidence of depression (HR: 1.32; 95% CI: 1.06, 1.65; P-trend = 0.001), although this association lost significance after the exclusion of early incident cases, suggesting possible reverse causation bias. Prebiotic consumption was not significantly associated with depression risk. Our study suggests that high consumption of whole-fat yogurt was related to a lower risk of depression in women of the SUN cohort. No association was observed for prebiotics. Further

Polyimine and its potential significance for prebiotic chemistry on Titan

NASA Astrophysics Data System (ADS)

Rahm, Martin; Lunine, Jonathan I.; Usher, David; Shalloway, David

2016-10-01

Hydrogen cyanide (HCN), a key reagent in prebiotic chemistry, is being generated in large amounts in the atmosphere of Titan. Contradictions between Cassini-Huygens measurements of the atmosphere and the surface of Titan, suggest that HCN is undergoing reaction chemistry, despite the frigid temperatures of 90-94 K. We will discuss computational results [1] investigating polyimine as one potential explanation for this observation. Polyimine is a polymer identified as the major component of polymerized HCN in laboratory experiments. It is flexible, which aids low temperature mobility, and it is able to form intermolecular and intramolecular =N-H...N hydrogen bonds, allowing for different polymorphs. Polymorphs have been predicted and explored by density functional theory coupled with a structure-searching algorithm. We have calculated the thermodynamics of polymerization, and show that polyimine is capable of absorbing light in a window of relative transparency in Titan's atmosphere. Light absorption and the possible catalytic functions of polyimine are suggestive of it driving photochemistry on the surface, with potential prebiotic implications.References:[1] M. Rahm, J. I. Lunine, D. Usher, D. Shalloway, "Polymorphism and electronic structure of polyimine and its potential significance for prebiotic chemistry on Titan", PNAS, early view. doi: 10.1073/pnas.1606634113

Probiotics and prebiotics in ulcerative colitis.

PubMed

Derikx, Lauranne A A P; Dieleman, Levinus A; Hoentjen, Frank

2016-02-01

The intestinal microbiota is one of the key players in the etiology of ulcerative colitis. Manipulation of this microflora with probiotics and prebiotics is an attractive strategy in the management of ulcerative colitis. Several intervention studies for both the induction and maintenance of remission in ulcerative colitis patients have been performed. Most of these studies evaluated VSL#3 or E. Coli Nissle 1917 and in general there is evidence for efficacy of these agents for induction and maintenance of remission. However, studies are frequently underpowered, lack a control group, and are very heterogeneous investigating different probiotic strains in different study populations. The absence of well-powered robust randomized placebo-controlled trials impedes the widespread use of probiotics and prebiotics in ulcerative colitis. However, given the promising results that are currently available, probiotics and prebiotics may find their way to the treatment algorithm for ulcerative colitis in the near future. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hepatic and peripheral glucose metabolism in intensive care patients receiving continuous high- or low-carbohydrate enteral nutrition.

PubMed

Tappy, L; Berger, M; Schwarz, J M; McCamish, M; Revelly, J P; Schneiter, P; Jéquier, E; Chioléro, R

1999-01-01

The suppression of endogenous glucose production during parenteral nutrition is impaired in critically ill patients. It is, however, unknown whether enteral administration of carbohydrates, which normally promote hepatic glucose uptake, improves hepatic glucose metabolism in such patients. We studied two groups of 7 patients during a 3-day continuous isocaloric enteral nutrition. A high-carbohydrate, low-lipid (EN-C) or a high-lipid, low-carbohydrate (EN-L) nutrient mixture was administered. Endogenous glucose production assessed with [2H7]glucose was similarly increased in both groups, indicating absence of its suppression by carbohydrate feeding. Gluconeogenesis estimated from [13C]glucose synthesis during [13C]bicarbonate infusion also was not suppressed by EN-C compared with EN-L. Systemic appearance of exogenous glucose was monitored by enteral infusion of [6,6-2H]glucose and was not different from the rate of glucose equivalent administered enterally, indicating no significant hepatic uptake of glucose in both groups. Plasma glucose and insulin concentrations were slightly higher with EN-C, although not significantly, and plasma triglycerides were similar in both groups. Both nutrition formulas were well tolerated clinically. These results indicate that enteral carbohydrate administration, whatever its quantity, fails to suppress endogenous glucose production and to promote net splanchnic glucose uptake in critically ill patients.

The Prebiotic Synthesis of Ethylenediamine Monoacetic Acid, The Repeating Unit of Peptide Nucleic Acids

NASA Technical Reports Server (NTRS)

Nelson, Kevin E.; Miller, Stanley L.

1992-01-01

The polymerization of ribonucleic acids or their precursors constitutes an important event in prebiotic chemistry. The various problems using ribonucleotides to make RNA suggest that there may have been a precursor. An attractive possibility are the peptide nucleic acids (PNA). PNAs are nucleotide analogs that make use of a polymer of ethylenediamine monoacetic acid (EDMA or 2-amninoethyl glycine) with the bases attached by an acetic acid. EDMA is an especially attractive alternative to the ribose phosphate or deoxyribose phosphate backbone because it contains no chiral centers and is potentially prebiotic, but there is no reported prebiotic synthesis. We have synthesized both EDMA and ethylenediamine diacetic acid (EDDA) from the prebiotic compounds ethylenediamine, formaldehyde, and hydrogen cyanide. The yields of EDMA range from 11 to 79% along with some sEDDA and uEDDA. These reactions work with concentrations of 10(exp -1)M and as low as 10(exp -4)M, and the reaction is likely to be effective at even lower concentrations. Ethylenediamine is a likely prebiotic compound, but it has not yet been demonstrated, although compounds such as ethanolamine and cysteamine have been proven to be prebiotic. Under neutral pH and heating at l00 C, EDMA is converted to the lactam, monoketopiperazine (MKP). The cyclization occurs and has an approximate ratio of MKP/EDMA = 3 at equilibrium. We have measured the solubilities of EDMA center dot H20 as 6.4 m, EDMA center dot HCl center dot H20 as 13.7 m, and EDMA center dot 2HCl center dot H20 as 3.4 m. These syntheses together with the high solubility of EDMA suggest that EDMA would concentrate in drying lagoons and might efficiently form polymers. Given the instability of ribose and the poor polymerizability of nucleotides, the prebiotic presence of EDMA and the possibility of its polymerization raises the possibility that PNAs are the progenitors of present day nucleic acids. A pre-RNA world may have existed in which PNAs or

Correlating molecular spectroscopy and molecular chemometrics to explore carbohydrate functional groups and utilization of coproducts from biofuel and biobrewing processing.

PubMed

Chen, Limei; Zhang, Xuewei; Yu, Peiqiang

2014-06-04

Dried distillers grains with solubles (DDGS) was coproducts from bioethanol and biobrewing industry. It was an excellent resource of protein and energy feedstuff in China. Conventional studies often focus on traditional nutritional profiles. To data, there is little research on molecular structure-nutrition interaction of carbohydrate in coproducts. In this study, five kinds of corn-grain based DDGS and two kinds of barley-grain based DDGS were collected from different manufactures in the north of China. They were coded as "1, 2, 3, 4, 5, 6, and 7", respectively. The primary purposes of this project were to investigate the molecular structure-nutrition interaction of carbohydrate in coproducts, in terms of (1) carbohydrate-related chemical composition and nutrient profiles, (2) predicted values for energy in coproducts for animal, and (3) in situ digestion of dry matter. The result showed that acid detergent fiber content in corn DDGS and barley DDGS had negative correlation with structural carbohydrate peak area, cellulose compounds, and carbohydrate component peaks (first, second, and total peak area), which were measured with molecular spectroscopy. The correlation between carbohydrate peak area (second and total) and digestible fiber (tdNDF) were negative. There were no correlation between carbohydrate spectral intensities and energy values, carbohydrate subfractions partitioned by CNCPS system, and in situ rumen degradation. The results indicate that carbohydrate spectral profiles (functional groups) are associated with the carbohydrate nutritive values in coproducts from biofuel and biobrewing processing.

Low-carbohydrate diet and type 2 diabetes risk in Japanese men and women: the Japan Public Health Center-Based Prospective Study.

PubMed

Nanri, Akiko; Mizoue, Tetsuya; Kurotani, Kayo; Goto, Atsushi; Oba, Shino; Noda, Mitsuhiko; Sawada, Norie; Tsugane, Shoichiro

2015-01-01

Evidence is sparse and contradictory regarding the association between low-carbohydrate diet score and type 2 diabetes risk, and no prospective study examined the association among Asians, who consume greater amount of carbohydrate. We prospectively investigated the association of low-carbohydrate diet score with type 2 diabetes risk. Participants were 27,799 men and 36,875 women aged 45-75 years who participated in the second survey of the Japan Public Health Center-Based Prospective Study and who had no history of diabetes. Dietary intake was ascertained by using a validated food-frequency questionnaire, and low-carbohydrate diet score was calculated from total carbohydrate, fat, and protein intake. The scores for high animal protein and fat or for high plant protein and fat were also calculated. Odds ratios of self-reported, physician-diagnosed type 2 diabetes over 5-year were estimated by using logistic regression. During the 5-year period, 1191 new cases of type 2 diabetes were self-reported. Low-carbohydrate diet score for high total protein and fat was significantly associated with a decreased risk of type 2 diabetes in women (P for trend <0.001); the multivariable-adjusted odds ratio of type 2 diabetes for the highest quintile of the score were 0.63 (95% confidence interval 0.46-0.84), compared with those for the lowest quintile. Additional adjustment for dietary glycemic load attenuated the association (odds ratio 0.75, 95% confidence interval 0.45-1.25). When the score separated for animal and for plant protein and fat, the score for high animal protein and fat was inversely associated with type 2 diabetes in women, whereas the score for high plant protein and fat was not associated in both men and women. Low-carbohydrate diet was associated with decreased risk of type 2 diabetes in Japanese women and this association may be partly attributable to high intake of white rice. The association for animal-based and plant-based low-carbohydrate diet warrants

Prebiotic effects of bovine lactoferrin on specific probiotic bacteria.

PubMed

Chen, Po-Wen; Liu, Zhen-Shu; Kuo, Tai-Chen; Hsieh, Min-Chi; Li, Zhe-Wei

2017-04-01

Bovine lactoferrin (bLf) is a natural iron-binding protein and it has been suggested to be a prebiotic agent, but this finding remains inconclusive. This study explores the prebiotic potential of bLf in 14 probiotics. Initially, bLf (1-32 mg/mL) treatment showed occasional and slight prebiotic activity in several probiotics only during the late experimental period (48, 78 h) at 37 °C. We subsequently supposed that bLf exerts stronger prebiotic effects when probiotic growth has been temperately retarded. Therefore, we incubated the probiotics at different temperatures, namely 37 °C, 28 °C, room temperature (approximately 22-24 °C), and 22 °C, to retard or inhibit their growth. As expected, bLf showed more favorable prebiotic activity in several probiotics when their growth was partially retarded at room temperature. Furthermore, at 22 °C, the growth of Bifidobacterium breve, Lactobacillus coryniformis, L. delbrueckii, L. acidophilus, B. angulatum, B. catenulatum, and L. paraplantarum were completely blocked. Notably, these probiotics started regrowing in the presence of bLf (1-32 mg/mL) in a significant and dose-dependent manner. Accordingly, bLf significantly increased the growth of Pediococcus pentosaceus, L. rhamnosus, and L. paracasei (BCRC 17483; a locally isolated strain) when their growth was retarded by incubation at 22 °C. In conclusion, bLf showed inconsistent prebiotic activity in the 14 probiotics at 37 °C, but revealed strong prebiotic activity in 10 probiotic strains at 22 °C. Therefore, this study enables determining additional roles of Lf in probiotic strains, which can facilitate developing novel combinational approaches by simultaneously using Lf and specific probiotics.

Low-Carb Diet: Could It Help You Lose Weight?

MedlinePlus

... body uses carbohydrates as its main fuel source. Complex carbohydrates (starches) are broken down into simple sugars during ... known as blood sugar (glucose). In general, natural complex carbohydrates are digested more slowly and they have less ...

Energy recovery from wastewater treatment plants through sludge anaerobic digestion: effect of low-organic-content sludge.

PubMed

Zhang, Yuyao; Li, Huan

2017-09-18

During anaerobic digestion, low-organic-content sludge sometimes is used as feedstock, resulting in deteriorated digestion performance. The operational experience of conventional anaerobic digestion cannot be applied to this situation. To investigate the feature of low-organic-content sludge digestion and explain its intrinsic mechanism, batch experiments were conducted using designed feedstock having volatile solids (VS) contents that were 30-64% of total solids (TS). The results showed that the accumulative biogas yield declined proportionally from 173.7 to 64.8 ml/g VS added and organic removal rate decreased from 34.8 to 11.8% with decreasing VS/TS in the substrate. The oligotrophic environment resulting from low-organic-content substrates led to decreased microbial activity and a switch from butyric fermentation to propionic fermentation. A first-order model described the biogas production from the batch experiments very well, and the degradation coefficient decreased from 0.159 to 0.069 day -1 , exhibiting a positive relation with organic content in substrate. The results observed here corroborated with data from published literature on anaerobic digestion of low-organic-content sludge and showed that it may not be feasible to recover energy from sludge with an organic content lower than 50% through mono digestion.

No influence of high- and low-carbohydrate diet on the oral glucose tolerance test in pregnancy.

PubMed

Buhling, Kai J; Elsner, Eva; Wolf, Christiane; Harder, Thomas; Engel, Barbara; Wascher, Cornelia; Siebert, Gerda; Dudenhausen, Joachim W

2004-04-01

Our objective was to determine the influence of the carbohydrate content of the diet preceding the oral glucose tolerance test (OGTT) in pregnancy on the test results and to evaluate the necessity of the recommended preparatory high-carbohydrate diet. Thirty-four women from our outpatient clinic were enrolled in this prospective study. After giving informed consent, each women underwent a 90-min lesson (supervised by a dietary assistant) covering the carbohydrate, protein and fat content of different foods. Women were then randomized and in a crossover design started a diet with either a low or a high carbohydrate content. We were aiming at a carbohydrate intake of 40% in the low-carbohydrate week (LCH) and 50% in the high-carbohydrate week (HCH). Compliance was monitored by a detailed food diary which the women kept and which included the weight of the foods they consumed. The actual dietary intakes as calculated from the food diaries showed that the mean caloric intake was 1801 +/- 314 kcal in the LCH and 2118 +/- 312 kcal in the HCH week (<0.001). During the LCH diet, CH intake was 39 +/- 6.1% and 49 +/- 6.6% in the HCH week (P < 0.001). The carbohydrate intake per kilogram bodyweight was 30 +/- 5.3 kcal vs. 35 +/- 5.2 kcal (P < 0.001). The number of patients diagnosed with gestational diabetes was two in the LCH and three in the HCH week (not significant). The sum of the OGTT values (fasting, 1 h and 2 h) after the LCH was 18.9 +/- 2.1 mmol/l vs. 18.8 +/- 2.1 mmol/l after the HCH (P = 0.51). No differences could be found in both groups regarding the fasting, 1-h, or 2-h glucose values. Including patients with a CH difference of at least 5%, 10%, and 15% carbohydrate between the weeks, we still did not observe any differences in the OGTT sum. We also looked at a possible influence of the CH content of the diet on the day before the test and of the last meal before the OGTT results and observed there was none. This is the first study which has observed the

Comparative Study of the Effects of a 1-Year Dietary Intervention of a Low-Carbohydrate Diet Versus a Low-Fat Diet on Weight and Glycemic Control in Type 2 Diabetes

PubMed Central

Davis, Nichola J.; Tomuta, Nora; Schechter, Clyde; Isasi, Carmen R.; Segal-Isaacson, C.J.; Stein, Daniel; Zonszein, Joel; Wylie-Rosett, Judith

2009-01-01

OBJECTIVE To compare the effects of a 1-year intervention with a low-carbohydrate and a low-fat diet on weight loss and glycemic control in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS This study is a randomized clinical trial of 105 overweight adults with type 2 diabetes. Primary outcomes were weight and A1C. Secondary outcomes included blood pressure and lipids. Outcome measures were obtained at 3, 6, and 12 months. RESULTS The greatest reduction in weight and A1C occurred within the first 3 months. Weight loss occurred faster in the low-carbohydrate group than in the low-fat group (P = 0.005), but at 1 year a similar 3.4% weight reduction was seen in both dietary groups. There was no significant change in A1C in either group at 1 year. There was no change in blood pressure, but a greater increase in HDL was observed in the low-carbohydrate group (P = 0.002). CONCLUSIONS Among patients with type 2 diabetes, after 1 year a low-carbohydrate diet had effects on weight and A1C similar to those seen with a low-fat diet. There was no significant effect on blood pressure, but the low-carbohydrate diet produced a greater increase in HDL cholesterol. PMID:19366978

Binturong (Arctictis binturong) and Kinkajou (Potos flavus) Digestive Strategy: Implications for Interpreting Frugivory in Carnivora and Primates

PubMed Central

Lambert, Joanna E.; Fellner, Vivek; McKenney, Erin; Hartstone-Rose, Adam

2014-01-01

Exclusive frugivory is rare. As a food resource, fruit is temporally and spatially patchy, low in protein, and variable in terms of energy yield from different carbohydrate types. Here, we evaluate the digestive physiology of two frugivorous Carnivora species (Potos flavus, Arctictis binturong) that converge with primates in a diversity of ecological and anatomical traits related to fruit consumption. We conducted feeding trials to determine mean digestive retention times (MRT) on captive animals at the Carnivore Preservation Trust (now Carolina Tiger Rescue), Pittsboro, NC. Fecal samples were collected on study subjects for in vitro analysis to determine methane, pH, and short chain fatty acid profiles; fiber was assayed using standard neutral detergent (NDF) and acid detergent (ADF) fiber methods. Results indicate that both carnivoran species have rapid digestive passage for mammals that consume a predominantly plant-based diet: A. binturong MRT = 6.5 hrs (0.3); P. flavus MRT = 2.5 hrs (1.6). In vitro experiments revealed no fermentation of structural polysaccharides – methane levels did not shift from 0 h to either 24 or 48 hours and no short chain fatty acids were detected. In both species, however, pH declined from one incubation period to another suggesting acidification and bacterial activity of microbes using soluble carbohydrates. A comparison with primates indicates that the study species are most similar in digestive retention times to Ateles – the most frugivorous anthropoid primate taxon. PMID:25157614

Potential Role of Inorganic Confined Environments in Prebiotic Phosphorylation.

PubMed

Dass, Avinash Vicholous; Jaber, Maguy; Brack, André; Foucher, Frédéric; Kee, Terence P; Georgelin, Thomas; Westall, Frances

2018-03-05

A concise outlook on the potential role of confinement in phosphorylation and phosphate condensation pertaining to prebiotic chemistry is presented. Inorganic confinement is a relatively uncharted domain in studies concerning prebiotic chemistry, and even more so in terms of experimentation. However, molecular crowding within confined dimensions is central to the functioning of contemporary biology. There are numerous advantages to confined environments and an attempt to highlight this fact, within this article, has been undertaken, keeping in context the limitations of aqueous phase chemistry in phosphorylation and, to a certain extent, traditional approaches in prebiotic chemistry.

Prebiotics and synbiotics in ulcerative colitis.

PubMed

Laurell, Axel; Sjöberg, Klas

2017-04-01

Ulcerative colitis (UC) is a chronic inflammatory disease of the colon with unclear pathogenesis. A dysbiotic intestinal microbiota is regarded as a key component in the disease process and there has been significant interest in developing new treatments which target the microbiota. To give an overview of the studies to date investigating prebiotics and synbiotics for the treatment of UC. A literature search of PubMed and related search engines was carried out using the terms "ulcerative colitis" in combination with "prebiotic", "synbiotic" or "dietary fibre". In total 17 studies on humans examining the effect of prebiotics in UC were found. Five major groups could be distinguished. Fructo-oligosaccharides were tried in six studies (mean 35 patients included, range 9-121). One study found a clinical response while two demonstrated indirect evidence of an effect. Germinated barley foodstuff was used in 8 studies (mean 38 patients, range 10-63). One study found an endoscopic response, while four noted a clinical response and two some indirect effects. Galacto-oligosaccharides, lactulose and resveratrol were used in one study each (mean 48 patients, range 41-52). One study found an endoscopic response and one a clinical response. There is yet inadequate evidence - especially in humans - to support any particular prebiotic in the clinical management of UC. However, due to the bulk of evidence supporting the effect of the microbiota on colonic inflammation, there is enough potential to justify further high-quality clinical trials investigating this subject.

Digestibility Is Similar between Commercial Diets That Provide Ingredients with Different Perceived Glycemic Responses and the Inaccuracy of Using the Modified Atwater Calculation to Calculate Metabolizable Energy

PubMed Central

Asaro, Natalie J.; Guevara, Marcial A.; Berendt, Kimberley; Zijlstra, Ruurd; Shoveller, Anna K.

2017-01-01

Dietary starch is required for a dry, extruded kibble; the most common diet type for domesticated felines in North America. However, the amount and source of dietary starch may affect digestibility and metabolism of other macronutrients. The objectives of this study were to evaluate the effects of 3 commercial cat diets on in vivo and in vitro energy and macronutrient digestibility, and to analyze the accuracy of the modified Atwater equation. Dietary treatments differed in their perceived glycemic response (PGR) based on ingredient composition and carbohydrate content (34.1, 29.5, and 23.6% nitrogen-free extract for High, Medium, and LowPGR, respectively). A replicated 3 × 3 Latin square design was used, with 3 diets and 3 periods. In vivo apparent protein, fat, and organic matter digestibility differed among diets, while apparent dry matter digestibility did not. Cats were able to efficiently digest and absorb macronutrients from all diets. Furthermore, the modified Atwater equation underestimated measured metabolizable energy by approximately 12%. Thus, the modified Atwater equation does not accurately determine the metabolizable energy of high quality feline diets. Further research should focus on understanding carbohydrate metabolism in cats, and establishing an equation that accurately predicts the metabolizable energy of feline diets. PMID:29117110

Assessment of Maillard reaction evolution, prebiotic carbohydrates, antioxidant activity and α-amylase inhibition in pulse flours.

PubMed

Moussou, Nadia; Corzo-Martínez, Marta; Sanz, María Luz; Zaidi, Farid; Montilla, Antonia; Villamiel, Mar

2017-03-01

In this paper, the quality of bean, chickpea, fava beans, lentil and pea flours from Algeria has been evaluated. Maillard reaction (MR) indicators, modifications in the carbohydrate and protein fractions, antioxidant activity and α-amylase inhibitor of raw, toasted and stored samples were evaluated. Fava beans, beans and peas showed higher content of raffinose family oligosaccharides while chickpeas and lentils showed higher polyol content. Toasting and storage caused slightly change in pulse quality; MR showed slight losses of lysine but increased antioxidant activity. Moreover, inhibition of α-amylase was slightly augmented during processing; this could increase the undigested carbohydrates that reach the colon, modulating the glycemic response. These results point out the suitability of these flours for preparing high-quality foodstuffs intended for a wide spectrum of the population, including hyperglycemic and gluten intolerant individuals.

Prebiotic synthesis of imidazole-4-acetaldehyde and histidine

NASA Astrophysics Data System (ADS)

Shen, Chun; Yang, Lily; Miller, Stanley L.; Oró, J.

1987-09-01

The prebiotic synthesis of imidazole-4-acetaldehyde and imidazole-4-glycol from erythrose and formamidine has been demonstrated as well as the prebiotic synthesis of imidazole-4-ethanol and imidazole-4-glycol from erythrose, formaldehyde and ammonia. The products were identified by TLC, HPLC, and LC-MS by comparison with authentic samples. The maximum yields of imidazole-4-acetaldehyde, imidazole-4-ethanol, and imidazole-4-glycol obtained in these reactions are 1.6, 5.4, 6.8% respectively, based on the erythrose. Imidazole-4-acetaldehyde would have been converted to histidine on the primitive earth by a Strecker synthesis, and several prebiotic reactions would convert imidazole-4-glycol and imidazole-4-ethanol to imidazole-4-acetaldehyde.

The abundance and variety of carbohydrate-active enzymes in the human gut microbiota.

PubMed

El Kaoutari, Abdessamad; Armougom, Fabrice; Gordon, Jeffrey I; Raoult, Didier; Henrissat, Bernard

2013-07-01

Descriptions of the microbial communities that live on and in the human body have progressed at a spectacular rate over the past 5 years, fuelled primarily by highly parallel DNA-sequencing technologies and associated advances in bioinformatics, and by the expectation that understanding how to manipulate the structure and functions of our microbiota will allow us to affect health and prevent or treat diseases. Among the myriad of genes that have been identified in the human gut microbiome, those that encode carbohydrate-active enzymes (CAZymes) are of particular interest, as these enzymes are required to digest most of our complex repertoire of dietary polysaccharides. In this Analysis article, we examine the carbohydrate-digestive capacity of a simplified but representative mini-microbiome in order to highlight the abundance and variety of bacterial CAZymes that are represented in the human gut microbiota.

Are Polyphosphates or Phosphate Esters Prebiotic Reagents?

NASA Technical Reports Server (NTRS)

Keefe, Anthony D.; Miller, Stanley L.

1995-01-01

It is widely held that there was a phosphate compound in prebiotic chemistry that played the role of adenosine triphosphate and that the first living organisms had ribose-phosphate in the backbone of their genetic material. However, there are no known efficient prebiotic synthesis of high-energy phosphates or phosphate esters. We review the occurrence of phosphates in nature, the efficiency of the volcanic synthesis of P4O10, the efficiency of polyphosphate synthesis by heating phosphate minerals under geological conditions, and the use of high-energy organic compounds such as cyanamide or hydrogen cyanide. These are shown to be inefficient processes especially when the hydrolysis of the polyphosphates is taken into account. For example, if a whole atmosphere of methane or carbon monoxide were converted to cyanide which somehow synthesized polyphosphates quantitatively, the polyphosphate concentration in the ocean would still have been insignificant. We also attempted to find more efficient high-energy polymerizing agents by spark discharge syntheses, but without success. There may still be undiscovered robust prebiotic syntheses of polyphosphates, or mechanisms for concentrating them, but we conclude that phosphate esters may not have been constituents of the first genetic material. Phosphoanhydrides are also unlikely as prebiotic energy sources.

Impaired Carbohydrate Digestion and Transport and Mucosal Dysbiosis in the Intestines of Children with Autism and Gastrointestinal Disturbances

PubMed Central

Williams, Brent L.; Hornig, Mady; Buie, Timothy; Bauman, Margaret L.; Cho Paik, Myunghee; Wick, Ivan; Bennett, Ashlee; Jabado, Omar; Hirschberg, David L.; Lipkin, W. Ian

2011-01-01

Gastrointestinal disturbances are commonly reported in children with autism, complicate clinical management, and may contribute to behavioral impairment. Reports of deficiencies in disaccharidase enzymatic activity and of beneficial responses to probiotic and dietary therapies led us to survey gene expression and the mucoepithelial microbiota in intestinal biopsies from children with autism and gastrointestinal disease and children with gastrointestinal disease alone. Ileal transcripts encoding disaccharidases and hexose transporters were deficient in children with autism, indicating impairment of the primary pathway for carbohydrate digestion and transport in enterocytes. Deficient expression of these enzymes and transporters was associated with expression of the intestinal transcription factor, CDX2. Metagenomic analysis of intestinal bacteria revealed compositional dysbiosis manifest as decreases in Bacteroidetes, increases in the ratio of Firmicutes to Bacteroidetes, and increases in Betaproteobacteria. Expression levels of disaccharidases and transporters were associated with the abundance of affected bacterial phylotypes. These results indicate a relationship between human intestinal gene expression and bacterial community structure and may provide insights into the pathophysiology of gastrointestinal disturbances in children with autism. PMID:21949732

Impaired carbohydrate digestion and transport and mucosal dysbiosis in the intestines of children with autism and gastrointestinal disturbances.

PubMed

Williams, Brent L; Hornig, Mady; Buie, Timothy; Bauman, Margaret L; Cho Paik, Myunghee; Wick, Ivan; Bennett, Ashlee; Jabado, Omar; Hirschberg, David L; Lipkin, W Ian

2011-01-01

Gastrointestinal disturbances are commonly reported in children with autism, complicate clinical management, and may contribute to behavioral impairment. Reports of deficiencies in disaccharidase enzymatic activity and of beneficial responses to probiotic and dietary therapies led us to survey gene expression and the mucoepithelial microbiota in intestinal biopsies from children with autism and gastrointestinal disease and children with gastrointestinal disease alone. Ileal transcripts encoding disaccharidases and hexose transporters were deficient in children with autism, indicating impairment of the primary pathway for carbohydrate digestion and transport in enterocytes. Deficient expression of these enzymes and transporters was associated with expression of the intestinal transcription factor, CDX2. Metagenomic analysis of intestinal bacteria revealed compositional dysbiosis manifest as decreases in Bacteroidetes, increases in the ratio of Firmicutes to Bacteroidetes, and increases in Betaproteobacteria. Expression levels of disaccharidases and transporters were associated with the abundance of affected bacterial phylotypes. These results indicate a relationship between human intestinal gene expression and bacterial community structure and may provide insights into the pathophysiology of gastrointestinal disturbances in children with autism.

ILSI Brazil International Workshop on Functional Foods: a narrative review of the scientific evidence in the area of carbohydrates, microbiome, and health

PubMed Central

Meheust, Agnès; Augustin, Livia; Benton, David; Berčík, Přemysl; Birkett, Anne; Eldridge, Alison L.; Faintuch, Joel; Hoffmann, Christian; Jones, Julie Miller; Kendall, Cyril; Lajolo, Franco; Perdigon, Gabriela; Prieto, Pedro Antonio; Rastall, Robert A.; Sievenpiper, John L.; Slavin, Joanne; de Menezes, Elizabete Wenzel

2013-01-01

To stimulate discussion around the topic of ‘carbohydrates’ and health, the Brazilian branch of the International Life Sciences Institute held the 11th International Functional Foods Workshop (1–2 December 2011) in which consolidated knowledge and recent scientific advances specific to the relationship between carbohydrates and health were presented. As part of this meeting, several key points related to dietary fiber, glycemic response, fructose, and impacts on satiety, cognition, mood, and gut microbiota were realized: 1) there is a need for global harmonization of a science-based fiber definition; 2) low-glycemic index foods can be used to modulate the postprandial glycemic response and may affect diabetes and cardiovascular outcomes; 3) carbohydrate type may influence satiety and satiation; glycemic load and glycemic index show links to memory, mood, and concentration; 4) validated biomarkers are needed to demonstrate the known prebiotic effect of carbohydrates; 5) negative effects of fructose are not evident when human data are systematically reviewed; 6) new research indicates that diet strongly influences the microbiome; and 7) there is mounting evidence that the intestinal microbiota has the ability to impact the gut–brain axis. Overall, there is much promise for development of functional foods that impact the microbiome and other factors relevant to health, including glycemic response (glycemic index/glycemic load), satiety, mood, cognition, and weight management. PMID:23399638

Cost-effectiveness model for a specific mixture of prebiotics in The Netherlands.

PubMed

Lenoir-Wijnkoop, I; van Aalderen, W M C; Boehm, G; Klaassen, D; Sprikkelman, A B; Nuijten, M J C

2012-02-01

The objective of this study was to assess the cost-effectiveness of the use of prebiotics for the primary prevention of atopic dermatitis in The Netherlands. A model was constructed using decision analytical techniques. The model was developed to estimate the health economic impact of prebiotic preventive disease management of atopic dermatitis. Data sources used include published literature, clinical trials and official price/tariff lists and national population statistics. The comparator was no supplementation with prebiotics. The primary perspective for conducting the economic evaluation was based on the situation in The Netherlands in 2009. The results show that the use of prebiotics infant formula (IMMUNOFORTIS(®)) leads to an additional cost of € 51 and an increase in Quality Adjusted Life Years (QALY) of 0.108, when compared with no prebiotics. Consequently, the use of infant formula with a specific mixture of prebiotics results in an incremental cost-effectiveness ratio (ICER) of € 472. The sensitivity analyses show that the ICER remains in all analyses far below the threshold of € 20,000/QALY. This study shows that the favourable health benefit of the use of a specific mixture of prebiotics results in positive short- and long-term health economic benefits. In addition, this study demonstrates that the use of infant formula with a specific mixture of prebiotics is a highly cost-effective way of preventing atopic dermatitis in The Netherlands.

Stability of Lactobacillus rhamnosus GG in prebiotic edible films

PubMed Central

Soukoulis, Christos; Behboudi-Jobbehdar, Solmaz; Yonekura, Lina; Parmenter, Christopher; Fisk, Ian D.

2014-01-01

The concept of prebiotic edible films as effective vehicles for encapsulating probiotic living cells is presented. Four soluble fibres (inulin, polydextrose, glucose-oligosaccharides and wheat dextrin) were selected as prebiotic co-components of gelatine based matrices plasticised with glycerol and used for the immobilisation of Lactobacillusrhamnosus GG. The addition of prebiotics was associated with a more compact and uniform film structure, with no detectable interspaces or micropores; probiotic inclusion did not significantly change the structure of the films. Glucose-oligosaccharides and polydextrose significantly enhanced L. rhamnosus GG viability during air drying (by 300% and 75%, respectively), whilst a 33% and 80% reduction in viable counts was observed for inulin and wheat dextrin. Contrarily, inulin was the most effective at controlling the sub-lethal effects on L. rhamnosus GG during storage. However, in all cases the supplementation of edible films with prebiotics ameliorated the storage stability of L. rhamnosus GG. PMID:24767059

Gene expression and activity of digestive enzymes of Daphnia pulex in response to food quality differences.

PubMed

Schwarzenberger, Anke; Fink, Patrick

2018-04-01

Food quality is an important factor influencing organisms' well-being. In freshwater ecosystems, food quality has been studied extensively for the keystone herbivore genus Daphnia, as they form the critical trophic link between primary producers and higher order consumers such as fish. For Daphnia, the edible fraction of phytoplankton in lakes (consisting mostly of unicellular algae and cyanobacteria) is extraordinarily diverse. To be able to digest different food particles, Daphnia possess a set of digestive enzymes that metabolize carbohydrates, lipids and proteins. Recent studies have found a connection between gene expression and activity of single digestive enzyme types of Daphnia, i.e. lipases and proteases, and transcriptome studies have shown that a variety of genes coding for gut enzymes are differentially expressed in response to different food algae. However, never before has a set of digestive enzymes been studied simultaneously both on the gene expression and the enzyme activity level in Daphnia. Here, we investigated several digestive enzymes of Daphnia pulex in a comparison between a high-quality (green algal) and a low-quality (cyanobacterial) diet. Diet significantly affected the expression of all investigated digestive enzyme genes and enzyme activity was altered between treatments. Furthermore, we found that gene expression and enzyme activity were significantly correlated in cellulase, triacylglycerol lipase and β-glucosidase when switched from high to low-quality food. We conclude that one of the factors causing the often observed low biomass and energy transfer efficiency from cyanobacteria to Daphnia is probably the switch to a cost-effective overall increase of gene expression and activity of digestive enzymes of this herbivore. Copyright © 2018 Elsevier Inc. All rights reserved.

Randomized controlled trial of changes in dietary carbohydrate/fat ratio and simple vs complex carbohydrates on body weight and blood lipids: the CARMEN study. The Carbohydrate Ratio Management in European National diets.

PubMed

Saris, W H; Astrup, A; Prentice, A M; Zunft, H J; Formiguera, X; Verboeket-van de Venne, W P; Raben, A; Poppitt, S D; Seppelt, B; Johnston, S; Vasilaras, T H; Keogh, G F

2000-10-01

To investigate the long-term effects of changes in dietary carbohydrate/fat ratio and simple vs complex carbohydrates. Randomized controlled multicentre trial (CARMEN), in which subjects were allocated for 6 months either to a seasonal control group (no intervention) or to one of three experimental groups: a control diet group (dietary intervention typical of the average national intake); a low-fat high simple carbohydrate group; or a low-fat high complex carbohydrate group. Three hundred and ninety eight moderately obese adults. The change in body weight was the primary outcome; changes in body composition and blood lipids were secondary outcomes. Body weight loss in the low-fat high simple carbohydrate and low-fat high complex carbohydrate groups was 0.9 kg (P < 0.05) and 1.8 kg (P < 0.001), while the control diet and seasonal control groups gained weight (0.8 and 0.1 kg, NS). Fat mass changed by -1.3kg (P< 0.01), -1.8kg (P< 0.001) and +0.6kg (NS) in the low-fat high simple carbohydrate, low-fat high complex carbohydrate and control diet groups, respectively. Changes in blood lipids did not differ significantly between the dietary treatment groups. Our findings suggest that reduction of fat intake results in a modest but significant reduction in body weight and body fatness. The concomitant increase in either simple or complex carbohydrates did not indicate significant differences in weight change. No adverse effects on blood lipids were observed. These findings underline the importance of this dietary change and its potential impact on the public health implications of obesity.

Renewable Hydrogen Carrier - Carbohydrate: Constructing the Carbon-Neutral Carbohydrate Economy

DTIC Science & Technology

2011-01-31

temperature. High fructose corn syrup , low-cost sucrose replacement, is made by stabilized glucose isomerase, which can work at ~60 °C for even about two...sustainable production, high -density storage, costly infrastructure, to eliminating safety concern. The use of renewable carbohydrate as a high -density...100% selectivity of enzymes, modest reaction conditions, and high -purity of generated hydrogen, carbohydrate is a promising hydrogen carrier for end

Potential Role of Inorganic Confined Environments in Prebiotic Phosphorylation

PubMed Central

Jaber, Maguy; Brack, André; Foucher, Frédéric; Kee, Terence P.; Westall, Frances

2018-01-01

A concise outlook on the potential role of confinement in phosphorylation and phosphate condensation pertaining to prebiotic chemistry is presented. Inorganic confinement is a relatively uncharted domain in studies concerning prebiotic chemistry, and even more so in terms of experimentation. However, molecular crowding within confined dimensions is central to the functioning of contemporary biology. There are numerous advantages to confined environments and an attempt to highlight this fact, within this article, has been undertaken, keeping in context the limitations of aqueous phase chemistry in phosphorylation and, to a certain extent, traditional approaches in prebiotic chemistry. PMID:29510574

Non Digestible Oligosaccharides Modulate the Gut Microbiota to Control the Development of Leukemia and Associated Cachexia in Mice.

PubMed

Bindels, Laure B; Neyrinck, Audrey M; Salazar, Nuria; Taminiau, Bernard; Druart, Céline; Muccioli, Giulio G; François, Emmanuelle; Blecker, Christophe; Richel, Aurore; Daube, Georges; Mahillon, Jacques; de los Reyes-Gavilán, Clara G; Cani, Patrice D; Delzenne, Nathalie M

2015-01-01

We tested the hypothesis that changing the gut microbiota using pectic oligosaccharides (POS) or inulin (INU) differently modulates the progression of leukemia and related metabolic disorders. Mice were transplanted with Bcr-Abl-transfected proB lymphocytes mimicking leukemia and received either POS or INU in their diet (5%) for 2 weeks. Combination of pyrosequencing, PCR-DGGE and qPCR analyses of the 16S rRNA gene revealed that POS decreased microbial diversity and richness of caecal microbiota whereas it increased Bifidobacterium spp., Roseburia spp. and Bacteroides spp. (affecting specifically B. dorei) to a higher extent than INU. INU supplementation increased the portal SCFA propionate and butyrate, and decreased cancer cell invasion in the liver. POS treatment did not affect hepatic cancer cell invasion, but was more efficient than INU to decrease the metabolic alterations. Indeed, POS better than INU delayed anorexia linked to cancer progression. In addition, POS treatment increased acetate in the caecal content, changed the fatty acid profile inside adipose tissue and counteracted the induction of markers controlling β-oxidation, thereby hampering fat mass loss. Non digestible carbohydrates with prebiotic properties may constitute a new nutritional strategy to modulate gut microbiota with positive consequences on cancer progression and associated cachexia.

Distant Site Effects of Ingested Prebiotics

PubMed Central

Collins, Stephanie; Reid, Gregor

2016-01-01

The gut microbiome is being more widely recognized for its association with positive health outcomes, including those distant to the gastrointestinal system. This has given the ability to maintain and restore microbial homeostasis a new significance. Prebiotic compounds are appealing for this purpose as they are generally food-grade substances only degraded by microbes, such as bifidobacteria and lactobacilli, from which beneficial short-chain fatty acids are produced. Saccharides such as inulin and other fructo-oligosaccharides, galactooligosaccharides, and polydextrose have been widely used to improve gastrointestinal outcomes, but they appear to also influence distant sites. This review examined the effects of prebiotics on bone strength, neural and cognitive processes, immune functioning, skin, and serum lipid profile. The mode of action is in part affected by intestinal permeability and by fermentation products reaching target cells. As the types of prebiotics available diversify, so too will our understanding of the range of microbes able to degrade them, and the extent to which body sites can be impacted by their consumption. PMID:27571098

Distant Site Effects of Ingested Prebiotics.

PubMed

Collins, Stephanie; Reid, Gregor

2016-08-26

The gut microbiome is being more widely recognized for its association with positive health outcomes, including those distant to the gastrointestinal system. This has given the ability to maintain and restore microbial homeostasis a new significance. Prebiotic compounds are appealing for this purpose as they are generally food-grade substances only degraded by microbes, such as bifidobacteria and lactobacilli, from which beneficial short-chain fatty acids are produced. Saccharides such as inulin and other fructo-oligosaccharides, galactooligosaccharides, and polydextrose have been widely used to improve gastrointestinal outcomes, but they appear to also influence distant sites. This review examined the effects of prebiotics on bone strength, neural and cognitive processes, immune functioning, skin, and serum lipid profile. The mode of action is in part affected by intestinal permeability and by fermentation products reaching target cells. As the types of prebiotics available diversify, so too will our understanding of the range of microbes able to degrade them, and the extent to which body sites can be impacted by their consumption.

A non-calorie-restricted low-carbohydrate diet is effective as an alternative therapy for patients with type 2 diabetes.

PubMed

Yamada, Yoshifumi; Uchida, Junichi; Izumi, Hisa; Tsukamoto, Yoko; Inoue, Gaku; Watanabe, Yuichi; Irie, Junichiro; Yamada, Satoru

2014-01-01

Although caloric restriction is a widely used intervention to reduce body weight and insulin resistance, many patients are unable to comply with such dietary therapy for long periods. The clinical effectiveness of low-carbohydrate diets was recently described in a position statement of Diabetes UK and a scientific review conducted by the American Diabetes Association. However, randomised trials of dietary interventions in Japanese patients with type 2 diabetes are scarce. Therefore, the aim of this study was to examine the effects of a non-calorie-restricted, low-carbohydrate diet in Japanese patients unable to adhere to a calorie-restricted diet. The enrolled patients were randomly allocated to receive a conventional calorie-restricted diet or low-carbohydrate diet. The patients received consultations every two months from a registered dietician for six months. We compared the effects of the two dietary interventions on glycaemic control and metabolic profiles. The HbA1c levels decreased significantly from baseline to six months in the low-carbohydrate diet group (baseline 7.6±0.4%, six months 7.0±0.7%, p=0.03) but not in the calorie-restricted group (baseline 7.7±0.6%, six months 7.5±1.0%, n.s.), (between-group comparison, p=0.03). The patients in the former group also experienced improvements in their triglyceride levels, without experiencing any major adverse effects or a decline in the quality of life. Our findings suggest that a low-carbohydrate diet is effective in lowering the HbA1c and triglyceride levels in patients with type 2 diabetes who are unable to adhere to a calorie-restricted diet.

Predicting water-soluble carbohydrates and ethanol-soluble carbohydrates in cool-season grasses with near-infrared reflectance spectroscopy

USDA-ARS?s Scientific Manuscript database

Grazing animals may require a high or low total nonstructural carbohydrate diet for optimal health and production. Understanding how nonstructural carbohydrates fluctuate in Kentucky pastures and being able to quantify and monitor nonstructural carbohydrates in a timely manner will greatly aid in m...

Low-carbohydrate diet in type 2 diabetes. Stable improvement of bodyweight and glycemic control during 22 months follow-up

PubMed Central

Nielsen, Jørgen Vesti; Joensson, Eva

2006-01-01

Background Low-carbohydrate diets in the management of obese patients with type 2 diabetes seem intuitively attractive due to their potent antihyperglycemic effect. We previously reported that a 20 % carbohydrate diet was significantly superior to a 55–60 % carbohydrate diet with regard to bodyweight and glycemic control in 2 non-randomised groups of obese diabetes patients observed closely over 6 months. The effect beyond 6 months of reduced carbohydrate has not been previously reported. The objective of the present study, therefore, was to determine to what degree the changes among the 16 patients in the low-carbohydrate diet group at 6-months were preserved or changed 22 months after start, even without close follow-up. In addition, we report that, after the 6 month observation period, two thirds of the patients in the high-carbohydrate changed their diet. This group also showed improvement in bodyweight and glycemic control. Method Retrospective follow-up of previously studied subjects on a low carbohydrate diet. Results The mean bodyweight at the start of the initial study was 100.6 ± 14.7 kg. At six months it was 89.2 ± 14.3 kg. From 6 to 22 months, mean bodyweight had increased by 2.7 ± 4.2 kg to an average of 92.0 ± 14.0 kg. Seven of the 16 patients (44%) retained the same bodyweight from 6 to 22 months or reduced it further; all but one had lower weight at 22 months than at the beginning. Initial mean HbA1c was 8.0 ± 1.5 %. After 6 and 12 months it was 6.6 ± 1.0 % and 7.0 ± 1.3 %, respectively. At 22 months, it was still 6.9 ± 1.1 %. Conclusion Advice on a 20 % carbohydrate diet with some caloric restriction to obese patients with type 2 diabetes has lasting effect on bodyweight and glycemic control. PMID:16774674

Manninotriose is a major carbohydrate in red deadnettle (Lamium purpureum, Lamiaceae)

PubMed Central

dos Santos, Raquel; Vergauwen, Rudy; Pacolet, Pieter; Lescrinier, Eveline; Van den Ende, Wim

2013-01-01

Background and Aims There is a great need to search for natural compounds with superior prebiotic, antioxidant and immunostimulatory properties for use in (food) applications. Raffinose family oligosaccharides (RFOs) show such properties. Moreover, they contribute to stress tolerance in plants, acting as putative membrane stabilizers, antioxidants and signalling agents. Methods A large-scale soluble carbohydrate screening was performed within the plant kingdom. An unknown compound accumulated to a high extent in early-spring red deadnettle (Lamium purpureum) but not in other RFO plants. The compound was purified and its structure was unravelled with NMR. Organs and organ parts of red deadnettle were carefully dissected and analysed for soluble sugars. Phloem sap content was analysed by a common EDTA-based method. Key Results Early-spring red deadnettle stems and roots accumulate high concentrations of the reducing trisaccharide manninotriose (Galα1,6Galα1,6Glc), a derivative of the non-reducing RFO stachyose (Galα1,6Galα1,6Glcα1,2βFru). Detailed soluble carbohydrate analyses on dissected stem and leaf sections, together with phloem sap analyses, strongly suggest that stachyose is the main transport compound, but extensive hydrolysis of stachyose to manninotriose seems to occur along the transport path. Based on the specificities of the observed carbohydrate dynamics, the putative physiological roles of manninotriose in red deadnettle are discussed. Conclusions It is demonstrated for the first time that manninotriose is a novel and important player in the RFO metabolism of red dead deadnettle. It is proposed that manninotriose represents a temporary storage carbohydrate in early-spring deadnettle, at the same time perhaps functioning as a membrane protector and/or as an antioxidant in the vicinity of membranes, as recently suggested for other RFOs and fructans. This novel finding urges further research on this peculiar carbohydrate on a broader array of RFO

Endogenous Synthesis of Prebiotic Organic Molecules

NASA Technical Reports Server (NTRS)

Miller, Stanley L.

1996-01-01

The necessary condition for the synthesis of organic compounds on the primitive earth is the presence of reducing conditions. This means an atmosphere of CH4, CO, or CO2 + H2. The atmospheric nitrogen can be N2 with a trace of NH3, but NH4(+) is needed in the ocean at least for amino acid synthesis. Many attempts have been made to use CO2 + H2O atmospheres for prebiotic synthesis, but these give at best extremely low yields of organic compounds, except in the presence of H2. Even strong reducing agents such as FeS + H2S or the mineral assemblages of the submarine vents fail to give significant yields of organic compounds with CO2. There appears to be a high kinetic barrier to the non-biological reduction of CO2 at low temperatures using geological reducing agents. The most abundant source of energy for prebiotic synthesis is ultraviolet light followed by electric discharges, with electric discharges being more efficient, although it is not clear which was the important energy source. Photochemical process would also make significant contributions. In an atmosphere Of CO2, N2, and H2O with no H2, the production rates of HCN and H2CO would be very low, 0.001 or less than that of a relatively reducing atmosphere. The concentration of organic compounds under these non-reducing conditions would be so low that there is doubt whether the concentration mechanism would be adequate for further steps toward the origin of life. A number of workers have calculated the influx of comets and meteorites on the primitive earth as a source of organic compounds. We conclude that while some organic material was added to the earth from comets and meteorites the amount available from these sources at a given time was at best only a few percent of that from earth bases syntheses under reducing conditions.

Effects of continuous low-carbohydrate diet after long-term exercise on GLUT-4 protein content in rat skeletal muscle.

PubMed

Kubota, M; Koshinaka, K; Kawata, Y; Koike, T; Oshida, Y

2008-01-01

Stimulation of AMPK and decreased glycogen levels in skeletal muscle have a deep involvement in enhanced insulin action and GLUT-4 protein content after exercise training. The present study examined the chronic effects of a continuous low-carbohydrate diet after long-term exercise on GLUT-4 protein content, glycogen content, AMPK, and insulin signaling in skeletal muscle. Rats were divided randomly into four groups: normal chow diet sedentary (N-Sed), low carbohydrate diet sedentary (L-Sed), normal chow diet exercise (N-Ex), and low carbohydrate diet exercise (L-Ex) groups. Rats in the exercise groups (N-Ex and L-Ex) were exercised by swimming for 6 hours/day in two 3-hour bouts separated by 45 minutes of rest. The 10-day exercise training resulted in a significant increase in the GLUT-4 protein content (p<0.01). Additionally, the GLUT-4 protein content in L-Ex rats was increased by 29% above that in N-Ex rats (p<0.01). Finally, the glycogen content in skeletal muscle of L-Ex rats was decreased compared with that of N-Ex rats. Taken together, we suggest that the maintenance of glycogen depletion after exercise by continuous low carbohydrate diet results in the increment of the GLUT-4 protein content in skeletal muscle.

Novel probiotics and prebiotics: road to the market.

PubMed

Kumar, Himanshu; Salminen, Seppo; Verhagen, Hans; Rowland, Ian; Heimbach, Jim; Bañares, Silvia; Young, Tony; Nomoto, Koji; Lalonde, Mélanie

2015-04-01

Novel probiotics and prebiotics designed to manipulate the gut microbiota for improving health outcomes are in demand as the importance of the gut microbiota in human health is revealed. The regulations governing introduction of novel probiotics and prebiotics vary by geographical region. Novel foods and foods with health claims fall under specific regulations in several countries. The paper reviews the main requirements of the regulations in the EU, USA, Canada and Japan. We propose a number of areas that need to be addressed in any safety assessment of novel probiotics and prebiotics. These include publication of the genomic sequence, antibiotic resistance profiling, selection of appropriate in vivo model, toxicological studies (including toxin production) and definition of target population. Copyright © 2014 Elsevier Ltd. All rights reserved.

Towards a more comprehensive concept for prebiotics.

PubMed

Bindels, Laure B; Delzenne, Nathalie M; Cani, Patrice D; Walter, Jens

2015-05-01

The essential role of the gut microbiota for health has generated tremendous interest in modulating its composition and metabolic function. One of these strategies is prebiotics, which typically refer to selectively fermented nondigestible food ingredients or substances that specifically support the growth and/or activity of health-promoting bacteria that colonize the gastrointestinal tract. In this Perspective, we argue that advances in our understanding of diet-microbiome-host interactions challenge important aspects of the current concept of prebiotics, and especially the requirement for effects to be 'selective' or 'specific'. We propose to revise this concept in an effort to shift the focus towards ecological and functional features of the microbiota more likely to be relevant for host physiology. This revision would provide a more rational basis for the identification of prebiotic compounds, and a framework by which the therapeutic potential of modulating the gut microbiota could be more fully materialized.

Apparent low ability of liver and muscle to adapt to variation of dietary carbohydrate:protein ratio in rainbow trout (Oncorhynchus mykiss).

PubMed

Skiba-Cassy, Sandrine; Panserat, Stéphane; Larquier, Mélanie; Dias, Karine; Surget, Anne; Plagnes-Juan, Elisabeth; Kaushik, Sadasivam; Seiliez, Iban

2013-04-28

The rainbow trout (Oncorhynchus mykiss) exhibits high dietary amino acid requirements and an apparent inefficiency to use dietary carbohydrates. Using this species, we investigated the metabolic consequences of long-term high carbohydrates/low protein feeding. Fish were fed two experimental diets containing either 20% carbohydrates/50% proteins (C20P50), or high levels of carbohydrates at the expense of proteins (35% carbohydrates/35% proteins--C35P35). The expression of genes related to hepatic and muscle glycolysis (glucokinase (GK), pyruvate kinase and hexokinase) illustrates the poor utilisation of carbohydrates irrespective of their dietary levels. The increased postprandial GK activity and the absence of inhibition of the gluconeogenic enzyme glucose-6-phosphatase activity support the hypothesis of the existence of a futile cycle around glucose phosphorylation extending postprandial hyperglycaemia. After 9 weeks of feeding, the C35P35-fed trout displayed lower body weight and feed efficiency and reduced protein and fat gains than those fed C20P50. The reduced activation of eukaryotic translation initiation factor 4-E binding protein 1 (4E-BP1) in the muscle in this C35P35 group suggests a reduction in protein synthesis, possibly contributing to the reduction in N gain. An increase in the dietary carbohydrate:protein ratio decreased the expression of genes involved in amino acid catabolism (serine dehydratase and branched-chain α-keto acid dehydrogenase E1α and E1β), and increased that of carnitine palmitoyltransferase 1, suggesting a higher reliance on lipids as energy source in fish fed high-carbohydrate and low-protein diets. This probably also contributes to the lower fat gain. Together, these results show that different metabolic pathways are affected by a high-carbohydrate/low-protein diet in rainbow trout.

Determination of "net carbohydrates" using high-performance anion exchange chromatography.

PubMed

Lilla, Zach; Sullivan, Darryl; Ellefson, Wayne; Welton, Kevin; Crowley, Rick

2005-01-01

For labeling purposes, the carbohydrate content of foods has traditionally been determined by difference. This value includes sugars, starches, fiber, dextrins, sugar alcohols, polydextrose, and various other organic compounds. In some cases, the current method may lack sufficient specificity, precision, and accuracy. These are subsequently quantitated by high performance anion exchange chromatography with pulsed amperometric detection and expressed as total nonfiber saccharides or percent "net carbohydrates." In this research, a new method was developed to address this need. The method consists of enzyme digestions to convert starches, dextrins, sugars, and polysaccharides to their respective monosaccharide components. These are subsequently quantified by high-performance anion exchange chromatography with pulsed amperometric detector and expressed as total nonfiber saccharides or percent "net carbohydrates." Hydrolyzed end products of various novel fibers and similar carbohydrates have been evaluated to ensure that they do not register as false positives in the new test method. The data generated using the "net carbohydrate" method were, in many cases, significantly different than the values produced using the traditional methodology. The recoveries obtained in a fortified drink matrix ranged from 94.9 to 105%. The coefficient of variation was 3.3%.

Gene-Silencing-Induced Changes in Carbohydrate Conformation in Relation to Bioenergy Value and Carbohydrate Subfractions in Modeled Plant (Medicago sativa) with Down-Regulation of HB12 and TT8 Transcription Factors

PubMed Central

Li, Xinxin; Hannoufa, Abdelali; Zhang, Yonggen; Yu, Peiqiang

2016-01-01

Gene silencing with RNA interference (RNAi) technology may be capable of modifying internal structure at a molecular level. This structural modification could affect biofunctions in terms of biodegradation, biochemical metabolism, and bioactive compound availability. The objectives of this study were to (1) Detect gene silencing-induced changes in carbohydrate molecular structure in an alfalfa forage (Medicago sativa spp. sativa: alfalfa) with down-regulation of genes that encode transcription factors TT8 and HB12; (2) Determine gene silencing-induced changes in nutrient bioutilization and bioavailability in the alfalfa forage (Medicago sativa); and (3) Quantify the correlation between gene silencing-induced molecular structure changes and the nutrient bioutilization and bioavailability in animals of ruminants. The experimental treatments included: T1 = Non-transgenic and no-gene silenced alfalfa forage (code “NT”); T2 = HB12-RNAi forage with HB12 gene down regulation (code “HB12”); T3 = TT8-RNAi forage with TT8 gene down regulation (code “TT8”). The HB12 and TT8 gene silencing-induced molecular structure changes were determined by non-invasive and non-destructive advanced molecular spectroscopy in a middle infrared radiation region that focused on structural, non-structural and total carbohydrate compounds. The nutrient bioutilization and bioavailability of the modified forage were determined using NRC-2001 system in terms of total digestive nutrient (TDN), truly digestible fiber (tdNDF), non-fiber carbohydrate (tdNDF), fatty acid (tdFA), crude protein (tdCP) and bioenergy profiles (digestible energy, metabolizable energy, net energy) for ruminants. The carbohydrate subfractions were evaluated using the updated CNCPS 6.0 system. The results showed that gene silencing significantly affected tdNFC (42.3 (NT) vs. 38.7 (HB12) vs. 37.4% Dry Matter (TT8); p = 0.016) and tdCP (20.8 (NT) vs. 19.4 (HB12) vs. 22.3% DM (TT8); p = 0.009). The gene-silencing also

Gene-Silencing-Induced Changes in Carbohydrate Conformation in Relation to Bioenergy Value and Carbohydrate Subfractions in Modeled Plant (Medicago sativa) with Down-Regulation of HB12 and TT8 Transcription Factors.

PubMed

Li, Xinxin; Hannoufa, Abdelali; Zhang, Yonggen; Yu, Peiqiang

2016-05-13

Gene silencing with RNA interference (RNAi) technology may be capable of modifying internal structure at a molecular level. This structural modification could affect biofunctions in terms of biodegradation, biochemical metabolism, and bioactive compound availability. The objectives of this study were to (1) Detect gene silencing-induced changes in carbohydrate molecular structure in an alfalfa forage (Medicago sativa spp. sativa: alfalfa) with down-regulation of genes that encode transcription factors TT8 and HB12; (2) Determine gene silencing-induced changes in nutrient bioutilization and bioavailability in the alfalfa forage (Medicago sativa); and (3) Quantify the correlation between gene silencing-induced molecular structure changes and the nutrient bioutilization and bioavailability in animals of ruminants. The experimental treatments included: T1 = Non-transgenic and no-gene silenced alfalfa forage (code "NT"); T2 = HB12-RNAi forage with HB12 gene down regulation (code "HB12"); T3 = TT8-RNAi forage with TT8 gene down regulation (code "TT8"). The HB12 and TT8 gene silencing-induced molecular structure changes were determined by non-invasive and non-destructive advanced molecular spectroscopy in a middle infrared radiation region that focused on structural, non-structural and total carbohydrate compounds. The nutrient bioutilization and bioavailability of the modified forage were determined using NRC-2001 system in terms of total digestive nutrient (TDN), truly digestible fiber (tdNDF), non-fiber carbohydrate (tdNDF), fatty acid (tdFA), crude protein (tdCP) and bioenergy profiles (digestible energy, metabolizable energy, net energy) for ruminants. The carbohydrate subfractions were evaluated using the updated CNCPS 6.0 system. The results showed that gene silencing significantly affected tdNFC (42.3 (NT) vs. 38.7 (HB12) vs. 37.4% Dry Matter (TT8); p = 0.016) and tdCP (20.8 (NT) vs. 19.4 (HB12) vs. 22.3% DM (TT8); p = 0.009). The gene-silencing also affected

Prebiotics and Probiotics and Oral Health

NASA Astrophysics Data System (ADS)

Meurman, J. H.

The first part of this chapter describes the unique characteristics of the mouth with special emphasis on the oral microbiota. Next, the highly prevalent dental diseases are briefly described together with more rare but still important diseases and symptoms of the mouth. Prevention and treatment of oral and dental diseases are also discussed focusing on aspects considered important with respect to the potential application of prebiotics and probiotics. The second part of the chapter then concentrates on research data on prebiotics and probiotics in the oral health perspective, ending up with conclusions and visions for future research.

Microbiota and prebiotics modulation of uremic toxin generation.

PubMed

Koppe, Laetitia; Fouque, Denis

2017-06-01

Recent data have shown that the host-intestinal microbiota interaction is intrinsically linked with overall health. Chronic kidney disease (CKD) could influence intestinal microbiota and gut dysbiosis is also considered as a cause of progression of kidney disease. An increasing body of evidence indicates that dysbiosis is a key contributor of uremic retention solutes (URS) accumulating in patients with CKD. The discovery of the kidney-gut axis has created new therapeutic opportunities for nutritional intervention in order to prevent adverse outcomes. One of these strategies is prebiotics, which refers to nondigestible food ingredients or substances that beneficial affect growth and/or activity of limited health-promoting bacteria in the gastrointestinal tract. The influence of prebiotics on the production and concentration of URS have been investigated in various animal and human CKD studies. However, to date, there is still paucity of high-quality intervention trials. Randomized controlled trials and adequately powered intervention studies are needed before recommending prebiotics in clinical practice. This review will outline the interconnection between CKD progression, dysbiosis and URS production and will discuss mechanisms of action and efficacy of prebiotics as a new CKD management tool, with a particular emphasis on URS generation.

Prebiotics for the management of hyperbilirubinemia in preterm neonates.

PubMed

Armanian, Amir Mohammad; Barekatain, Behzad; Hoseinzadeh, Maryam; Salehimehr, Nima

2016-09-01

We evaluated if prebiotics have benefits for the management of hyperbilirubinemia in preterm neonates. Preterm neonates were entered into the study when enteral feeding volume met 30 mL/kg/day. They randomly received a mixture of short-chain galacto-oligosacarids/long-chain fructo-oligosacarids or distilled water (placebo) for 1 week. Total serum bilirubin level was measured by transcutaneous bilirubinometry. Stool frequency and meeting full enteral feeding during the study period were considered as secondary outcomes. Twenty-five neonates in each group completed the trial. Bilirubin level was decreased with the prebiotic (-1.3 ±  1.8 mg/dL, p = 0.004), but not placebo (-0.1 ± 3.3 mg/dL, p = 0.416). Peak bilirubin level was lower with the prebiotic than placebo (8.3 ± 1.7 versus 10.1 ± 2.2 mg/dL, p = 0.003). Stool frequency was increased with the prebiotic (0.7 ± 1.9 defecation/day, p = 0.014), but not with placebo (0.6 ±  1.5 defecation/day, p = 0.133). Average stool frequency (2.4 ±  0.4 versus 1.9 ± 0.5 defecation/day, p = 0.003) and frequently of meeting full enteral feeding (60% versus 16%, p = 0.002) were higher with the prebiotic than placebo. Prebiotic oligosaccharides increase stool frequency, improve feeding tolerance and reduce bilirubin level in preterm neonates and therefore can be efficacious for the management of neonatal hyperbilirubinemia.

Micronutrients, N-Acetyl Cysteine, Probiotics and Prebiotics, a Review of Effectiveness in Reducing HIV Progression

PubMed Central

Hummelen, Ruben; Hemsworth, Jaimie; Reid, Gregor

2010-01-01

Low serum concentrations of micronutrients, intestinal abnormalities, and an inflammatory state have been associated with HIV progression. These may be ameliorated by micronutrients, N-acetyl cysteine, probiotics, and prebiotics. This review aims to integrate the evidence from clinical trials of these interventions on the progression of HIV. Vitamin B, C, E, and folic acid have been shown to delay the progression of HIV. Supplementation with selenium, N-acetyl cysteine, probiotics, and prebiotics has considerable potential, but the evidence needs to be further substantiated. Vitamin A, iron, and zinc have been associated with adverse effects and caution is warranted for their use. PMID:22254046

Ketoacidosis due to a Low-carbohydrate Diet in an Elderly Woman with Dementia and Abnormal Eating Behavior

PubMed Central

Iwata, Hitoshi; Tsuzuki, Seiichiro; Iwata, Mitsunaga; Terasawa, Teruhiko

2017-01-01

Strict restriction of carbohydrates can induce symptomatic ketoacidosis. We herein report a 76-year-old demented woman who developed ketoacidosis after 1 month of abnormal eating behavior involving selectively eating hamburger steak (estimated carbohydrate =12.7 g/day). Laboratory tests showed high-anion-gap metabolic acidosis with elevated blood ketone levels. She was successfully treated with intravenous fluids followed by oral intake of a regular diet. She remained relapse-free after correcting her eating habits. Healthcare providers should know that abnormal eating behavior in demented people can lead to an extremely-low-carbohydrate diet and cause atypical ketoacidosis unexplained by diabetes, heavy alcohol intake, or starvation conditions. PMID:28883241

Ketoacidosis due to a Low-carbohydrate Diet in an Elderly Woman with Dementia and Abnormal Eating Behavior.

PubMed

Iwata, Hitoshi; Tsuzuki, Seiichiro; Iwata, Mitsunaga; Terasawa, Teruhiko

2017-10-01

Strict restriction of carbohydrates can induce symptomatic ketoacidosis. We herein report a 76-year-old demented woman who developed ketoacidosis after 1 month of abnormal eating behavior involving selectively eating hamburger steak (estimated carbohydrate =12.7 g/day). Laboratory tests showed high-anion-gap metabolic acidosis with elevated blood ketone levels. She was successfully treated with intravenous fluids followed by oral intake of a regular diet. She remained relapse-free after correcting her eating habits. Healthcare providers should know that abnormal eating behavior in demented people can lead to an extremely-low-carbohydrate diet and cause atypical ketoacidosis unexplained by diabetes, heavy alcohol intake, or starvation conditions.

THE IMPORTANCE OF DIETARY CARBOHYDRATE IN HUMAN EVOLUTION.

PubMed

Hardy, Karen; Brand-Miller, Jennie; Brown, Katherine D; Thomas, Mark G; Copeland, Les

2015-09-01

ABSTRACT We propose that plant foods containing high quantities of starch were essential for the evolution of the human phenotype during the Pleistocene. Although previous studies have highlighted a stone tool-mediated shift from primarily plant-based to primarily meat-based diets as critical in the development of the brain and other human traits, we argue that digestible carbohydrates were also necessary to accommodate the increased metabolic demands of a growing brain. Furthermore, we acknowledge the adaptive role cooking played in improving the digestibility and palatability of key carbohydrates. We provide evidence that cooked starch, a source of preformed glucose, greatly increased energy availability to human tissues with high glucose demands, such as the brain, red blood cells, and the developing fetus. We also highlight the auxiliary role copy number variation in the salivary amylase genes may have played in increasing the importance of starch in human evolution following the origins of cooking. Salivary amylases are largely ineffective on raw crystalline starch, but cooking substantially increases both their energy-yielding potential and glycemia. Although uncertainties remain regarding the antiquity of cooking and the origins of salivary amylase gene copy number variation, the hypothesis we present makes a testable prediction that these events are correlated.

Structural and electronic properties of barbituric acid and melamine-containing ribonucleosides as plausible components of prebiotic RNA: implications for prebiotic self-assembly.

PubMed

Kaur, Sarabjeet; Sharma, Purshotam; Wetmore, Stacey D

2017-11-22

The RNA world hypothesis assumes that RNA was the first informational polymer that originated from prebiotic chemical soup. However, since the reaction of d-ribose with canonical nucleobases (A, C, G and U) fails to yield ribonucleosides (rNs) in substantial amounts, the spontaneous origin of rNs and the subsequent synthesis of RNA remains an unsolved mystery. To this end, it has been suggested that RNA may have evolved from primitive genetic material (preRNA) composed of simpler prebiotic heterocycles that spontaneously form glycosidic bonds with ribose. As an effort toward evaluating this hypothesis, the present study uses density functional theory (DFT) to assess the suitability of barbituric acid (BA) and melamine (MM) to act as prebiotic nucleobases, both of which have recently been shown to spontaneously form a glycosidic bond with ribose and organize into supramolecular assemblies in solution. The significant strength of hydrogen bonds involving BA and MM indicates that such interactions may have played a crucial role in their preferential selection over competing heterocycles that interact solely through stacking interactions from the primordial soup during the early phase of evolution. However, the greater stability of stacked dimers involving BA or MM and the canonical nucleobases compared to those consisting solely of BA and/or MM points towards the possible evolution of intermediate informational polymers consisting of prebiotic and canonical nucleobases, which could have eventually evolved into RNA. Analysis of the associated rNs reveals an anti conformational preference for the biologically-relevant β-anomer of both BA and MM rNs, which will allow complementary WC-like hydrogen bonding that can stabilize preRNA polymers. Large calculated deglycosylation barriers suggest BA rNs containing C-C glycosidic bonds are relevant in challenging prebiotic environments such as volcanic geotherms, while lower barriers indicate the MM rNs containing C

Low cost digester monitoring under realistic conditions: Rural use of biogas and digestate quality.

PubMed

Castro, L; Escalante, H; Jaimes-Estévez, J; Díaz, L J; Vecino, K; Rojas, G; Mantilla, L

2017-09-01

The purpose of this work was to assess the behaviour of anaerobic digestion of cattle manure in a rural digester under realistic conditions, and estimate the quality and properties of the digestate. The data obtained during monitoring indicated that the digester operation was stable without risk of inhibition. It produced an average of 0.85Nm 3 biogas/d at 65.6% methane, providing an energy savings of 76%. In addition, the digestate contained high nutrient concentrations, which is an important feature of fertilizers. However, this method requires post-treatment due to the presence of pathogens. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influence of different prebiotics and mode of their administration on broiler chicken performance.

PubMed

Bednarczyk, M; Stadnicka, K; Kozłowska, I; Abiuso, C; Tavaniello, S; Dankowiakowska, A; Sławińska, A; Maiorano, G

2016-08-01

In the post-antibiotics era, prebiotics are proposed as alternatives to antibiotic growth promoters in poultry production. The goal of this study was to compare in ovo method of prebiotic delivery with in-water supplementation and with both methods combined (in ovo+in-water) in broiler chickens. Two trials were conducted. Trial 1 was carried out to optimize the doses of two prebiotics, DN (DiNovo®, extract of beta-glucans) and BI (Bi2tos, trans-galactooligosaccharides), for in ovo delivery. The estimated parameters were hatchability and bacteriological status of the newly hatched chicks. Prebiotics were dissolved in 0.2 ml of physiological saline, at the doses: 0.18, 0.88, 3.5 and 7.0 mg/embryo; control group (C) was injected in ovo with 0.2 ml of physiological saline. Trial 2 was conducted to evaluate effects of different prebiotics (DN, BI and raffinose family oligosaccharides (RFO)) delivered in ovo, in-water and in a combined way (in ovo+in-water) on broiler chickens performance. The results of the Trial 1 indicated that the optimal dose of DN and BI prebiotics delivered in ovo, that did not reduce chicks' hatchability, was 0.88 mg/embryo (DN) and 3.5 mg/embryo (BI). Both prebiotics numerically increased number of lactobacilli and bifidobacteria in chicken feces (P>0.05). In Trial 2, all prebiotics (DN, BI and RFO) significantly increased BW gain compared with the C group (P<0.05), especially during the first 21 days of life. However, feed intake and feed conversion ratio were increased upon prebiotics delivery irrespective of method used. Injection of prebiotics in ovo combined with in-water supplementation did not express synergistic effects on broilers performance compared with in ovo injection only. Taken together, those results confirm that single in ovo prebiotics injection into the chicken embryo can successfully replace prolonged in-water supplementation post hatching.

Structural analysis of N-linked carbohydrate chains of funnel web spider (Agelenopsis aperta) venom peptide isomerase.

PubMed

Shikata, Y; Ohe, H; Mano, N; Kuwada, M; Asakawa, N

1998-06-01

The structure of the N-linked carbohydrate chains of peptide isomerase from the venom of the funnel web spider (Agelenopsis aperta) has been analyzed. Carbohydrates were released from peptide isomerase by hydrazinolysis and reductively aminated with 2-aminopyridine. The fluorescent derivatives were purified by phenol/chloroform extraction, followed by size-exclusion HPLC. The structure of the purified pyridylamino (PA-) carbohydrate chains were analyzed by a combination of two-dimensional HPLC mapping, sugar composition analysis, sequential exoglycosidase digestions, and mass spectrometry. The peptide isomerase contains six kinds of N-linked carbohydrate chains of truncated high-mannose type, with a fucose alpha 1-6 linked to the reducing N-acetylglucosamine in approximately 80% of them.

In ovo validation model to assess the efficacy of commercial prebiotics on broiler performance and oxidative stability of meat.

PubMed

Maiorano, Giuseppe; Stadnicka, Katarzyna; Tavaniello, Siria; Abiuso, Cinzia; Bogucka, Joanna; Bednarczyk, Marek

2017-02-01

The purpose of this study was to examine the effect of in ovo injection of 2 different prebiotics, DiNovo (DN; Laminaria spp., extract containing laminarin and fucoidan) and Bi 2 tos (BI; non-digestive trans-galactooligosaccharides from milk lactose digested with Bifidobacterium bifidum NCIMB 41171), on growth, slaughter traits, intramuscular fat percentage (IF) and muscle fiber diameter, and lipid oxidation of meat in chickens reared under commercial conditions, following an in ovo trial protocol. On d 12 of embryonic incubation, 350,560 Ross 308 eggs were randomly divided into 3 experimental groups and automatically injected in ovo with: physiological saline (control group), BI at dose of 3.5 mg/embryo and DN at dose of 0.88 mg/embryo. Hatched chicks (males and females) were allocated dependent on treatment group into 3 poultry houses on each farm (3 farms in total) with a stocking density of 21.2 to 21.5 chicks/m 2 At 42 d of age, 14 randomly chosen birds (7 males and 7 females), per each treatment from each farm, were individually weighed and slaughtered. The results showed no significant differences of final number of chickens/chicken house, mortality, BW per treatment, stocking density (kg/m 2 ), feed intake, feed conversion rate (FCR), and European Broiler Index among 3 experimental groups. Treatments with BI and DN were associated with slight increases (P > 0.05) in average BW and a minor improvement (P > 0.05) of FCR in BI group. Slaughtered chickens from DN and BI treated groups had significantly increase of BW, carcass weight, carcass yield, and breast muscle weight compared with the control group. IF and muscle fiber diameter were similar among groups. Males had significantly higher slaughter traits compared to females, except for breast muscle yield. The prebiotic treatments led to a higher lipid oxidation in meat, even if the detected TBA reactive substances were below the critical value recognized for meat acceptability. In conclusion, in ovo

Baroreflex sensitivity in acute hypoxia and carbohydrate loading.

PubMed

Klemenc, Matjaž; Golja, Petra

2011-10-01

Hypoxia decreases baroreflex sensitivity (BRS) and can be a sufficient cause for syncope in healthy individuals. Carbohydrate loading enhances efferent sympathetic activity, which affects cardiac contractility, heart rate and vascular resistance, the main determinants of blood pressure. Thus, in both normoxia and hypoxia, carbohydrate loading may be more than simply metabolically beneficial, as it may affect blood pressure regulation. We hypothesised that carbohydrate loading will, in both normoxia and hypoxia, alter the regulation of blood pressure, as reflected in a change in baroreflex sensitivity. Fourteen subjects participated in two experiments, composed of a 15-min normoxic period, after which the subjects ingested water or an equal amount of water with carbohydrates. A 30-min rest period was then followed by a 10-min second normoxic and a 30-min hypoxic period. Blood pressure and heart rate were monitored continuously during the experiment to determine BRS. Despite an increased sympathetic activation, reflected in increased heart rate (P < 0.001) BRS was lower (P < 0.01) after carbohydrate loading, as compared to the water experiment, in both normoxic [23.7 (12.4) versus 28.8 (13.8) ms/mmHg] and hypoxic [16.8 (11.0) versus 24.3 (12.3) ms/mmHg] phases of the present study. As BRS was decreased in acute hypoxic exposure, the results confirm that hypoxia interferes with blood pressure regulation. However, although oral carbohydrate loading induced sympathoexcitation, it did not improve blood pressure regulation in hypoxia, as evident from the BRS data. Baroreflex effects of other forms of carbohydrate loading, not causing postprandial blood shifts to digestive system, should therefore be investigated.

Effect of a 6-month vegan low-carbohydrate (‘Eco-Atkins’) diet on cardiovascular risk factors and body weight in hyperlipidaemic adults: a randomised controlled trial

PubMed Central

Jenkins, David J A; Wong, Julia M W; Kendall, Cyril W C; Esfahani, Amin; Ng, Vivian W Y; Leong, Tracy C K; Faulkner, Dorothea A; Vidgen, Ed; Paul, Gregory; Mukherjea, Ratna; Krul, Elaine S; Singer, William

2014-01-01

Objective Low-carbohydrate diets may be useful for weight loss. Diets high in vegetable proteins and oils may reduce the risk of coronary heart disease. The main objective was to determine the longer term effect of a diet that was both low-carbohydrate and plant-based on weight loss and low-density lipoprotein cholesterol (LDL-C). Design, setting, participants A parallel design study of 39 overweight hyperlipidaemic men and postmenopausal women conducted at a Canadian university-affiliated hospital nutrition research centre from April 2005 to November 2006. Intervention Participants were advised to consume either a low-carbohydrate vegan diet or a high-carbohydrate lacto-ovo vegetarian diet for 6 months after completing 1-month metabolic (all foods provided) versions of these diets. The prescribed macronutrient intakes for the low-carbohydrate and high-carbohydrate diets were: 26% and 58% of energy from carbohydrate, 31% and 16% from protein and 43% and 25% from fat, respectively. Primary outcome Change in body weight. Results 23 participants (50% test, 68% control) completed the 6-month ad libitum study. The approximate 4 kg weight loss on the metabolic study was increased to −6.9 kg on low-carbohydrate and −5.8 kg on high-carbohydrate 6-month ad libitum treatments (treatment difference (95% CI) −1.1 kg (−2.1 to 0.0), p=0.047). The relative LDL-C and triglyceride reductions were also greater on the low-carbohydrate treatment (treatment difference (95% CI) −0.49 mmol/L (−0.70 to −0.28), p<0.001 and −0.34 mmol/L (−0.57 to −0.11), p=0.005, respectively), as were the total cholesterol:HDL-C and apolipoprotein B:A1 ratios (−0.57 (−0.83, −0.32), p<0.001 and −0.05 (−0.09, −0.02), p=0.003, respectively). Conclusions A self-selected low-carbohydrate vegan diet, containing increased protein and fat from gluten and soy products, nuts and vegetable oils, had lipid lowering advantages over a high-carbohydrate, low-fat weight loss

A low-carbohydrate diet is more effective in reducing body weight than healthy eating in both diabetic and non-diabetic subjects.

PubMed

Dyson, P A; Beatty, S; Matthews, D R

2007-12-01

Low-carbohydrate diets are effective for weight reduction in people without diabetes, but there is limited evidence for people with Type 2 diabetes. Aims To assess the impact of a low-carbohydrate diet on body weight, glycated haemoglobin (HbA(1c)), ketone and lipid levels in diabetic and non-diabetic subjects. Thirteen Type 2 diabetic subjects (on diet or metformin) and 13 non-diabetic subjects were randomly allocated to either a low-carbohydrate diet (< or = 40 g carbohydrate/day) or a healthy-eating diet following Diabetes UK nutritional recommendations and were seen monthly for 3 months. Subjects (25% male) were (mean +/- sd) age 52 +/- 9 years, weight 96.3 +/- 16.6 kg, body mass index 35.1 kg/m(2), HbA(1c) 6.6 +/- 1.1%, total cholesterol 5.1 +/- 1.1 mmol/l, high-density lipoprotein cholesterol 1.3 +/- 0.4 mmol/l, low-density lipoprotein cholesterol 3.1 +/- 0.9 mmol/l, triglycerides (geometric mean) 1.55 (1.10, 2.35) mmol/l and ketones range 0.0-0.2 mmol/l. Analysis was by intention to treat with last observation carried forward. Twenty-two of the participants (85%) completed the study. Weight loss was greater (6.9 vs. 2.1 kg, P = 0.003) in the low-carbohydrate group, with no difference in changes in HbA(1c), ketone or lipid levels. The diet was equally effective in those with and without diabetes.

Influence of the UV Environment on the Synthesis of Prebiotic Molecules.

PubMed

Ranjan, Sukrit; Sasselov, Dimitar D

2016-01-01

Ultraviolet radiation is common to most planetary environments and could play a key role in the chemistry of molecules relevant to abiogenesis (prebiotic chemistry). In this work, we explore the impact of UV light on prebiotic chemistry that might occur in liquid water on the surface of a planet with an atmosphere. We consider effects including atmospheric absorption, attenuation by water, and stellar variability to constrain the UV input as a function of wavelength. We conclude that the UV environment would be characterized by broadband input, and wavelengths below 204 nm and 168 nm would be shielded out by atmospheric CO2 and water, respectively. We compare this broadband prebiotic UV input to the narrowband UV sources (e.g., mercury lamps) often used in laboratory studies of prebiotic chemistry and explore the implications for the conclusions drawn from these experiments. We consider as case studies the ribonucleotide synthesis pathway of Powner et al. (2009) and the sugar synthesis pathway of Ritson and Sutherland (2012). Irradiation by narrowband UV light from a mercury lamp formed an integral component of these studies; we quantitatively explore the impact of more realistic UV input on the conclusions that can be drawn from these experiments. Finally, we explore the constraints solar UV input places on the buildup of prebiotically important feedstock gasses like CH4 and HCN. Our results demonstrate the importance of characterizing the wavelength dependence (action spectra) of prebiotic synthesis pathways to determine how pathways derived under laboratory irradiation conditions will function under planetary prebiotic conditions.

Cyclodextrins in Food Technology and Human Nutrition: Benefits and Limitations.

PubMed

Fenyvesi, É; Vikmon, M; Szente, L

2016-09-09

Cyclodextrins are tasteless, odorless, nondigestible, noncaloric, noncariogenic saccharides, which reduce the digestion of carbohydrates and lipids. They have low glycemic index and decrease the glycemic index of the food. They are either non- or only partly digestible by the enzymes of the human gastrointestinal (GI) tract and fermented by the gut microflora. Based on these properties, cyclodextrins are dietary fibers useful for controlling the body weight and blood lipid profile. They are prebiotics, improve the intestinal microflora by selective proliferation of bifidobacteria. These antiobesity and anti-diabetic effects make them bioactive food supplements and nutraceuticals. In this review, these features are evaluated for α-, β- and γ-cyclodextrins, which are the cyclodextrin variants approved by authorities for food applications. The mechanisms behind these effects are reviewed together with the applications as solubilizers, stabilizers of dietary lipids, such as unsaturated fatty acids, phytosterols, vitamins, flavonoids, carotenoids and other nutraceuticals. The recent applications of cyclodextrins for reducing unwanted components, such as trans-fats, allergens, mycotoxins, acrylamides, bitter compounds, as well as in smart active packaging of foods are also overviewed.

Effect of biochar addition on hydrogen and methane production in two-phase anaerobic digestion of aqueous carbohydrates food waste.

PubMed

Sunyoto, Nimas M S; Zhu, Mingming; Zhang, Zhezi; Zhang, Dongke

2016-11-01

Effect of biochar addition on hydrogen and methane production in two-phase anaerobic digestion of aqueous carbohydrates was studied using bench-scale bioreactors. The cultures with biochar additions were placed in 100ml reactors and incubated at 35°C and pH 5 for hydrogen production. The residual cultures were then used for methane production, incubated at 35°C and pH 7. Daily yields of hydrogen and methane and weekly yield of volatile fatty acids (VFA) were measured. The hydrogen and methane production potentials, rate and lag phases of the two phases were analysed using the Gompertz model. The results showed that biochar addition increased the maximum production rates of hydrogen by 32.5% and methane 41.6%, improved hydrogen yield by 31.0% and methane 10.0%, and shortened the lag phases in the two phases by 36.0% and 41.0%, respectively. Biochar addition also enhanced VFA generation during hydrogen production and VFA degradation in methane production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prebiotics and probiotics: the prevention and reduction in severity of atopic dermatitis in children.

PubMed

Foolad, N; Armstrong, A W

2014-06-01

The purpose of this review was to identify whether supplementation with prebiotics and/or probiotics help prevent the development or reduce the severity of atopic dermatitis in children less than three years of age. Since 1997, immunostimulatory supplements, such as prebiotics and probiotics, have been investigated. Various supplementations include probiotics (single strain or mix), probiotics with formula, probiotics mix with prebiotics, and prebiotics. In this narrative review, we examined 13 key articles on prebiotics and/or probiotics, and their effects on infant atopic dermatitis. Among the selected studies, a total of 3,023 participants received supplements or placebo. Eight out of the 13 (61.5%) studies reported a significant effect on the prevention of atopic dermatitis after supplementation with probiotics and/or prebiotics. Five out of the 13 (38.5%) studies indicated significant reduction in the severity of atopic dermatitis after supplementation. Based on the available studies, supplementation with certain probiotics (Lactobacillus rhamnosus GG) appears to be an effective approach for the prevention and reduction in severity of atopic dermatitis. A mix of specific probiotic strains prevented atopic dermatitis among infants. Based on studies with prebiotics, there was a long-term reduction in the incidence of atopic dermatitis. Supplementation with prebiotics and probiotics appears useful for the reduction in the severity of atopic dermatitis. Additional interventional studies exploring prebiotics and probiotics are imperative before recommendations can be made.

Oligosaccharides in infant formula: more evidence to validate the role of prebiotics.

PubMed

Vandenplas, Yvan; Zakharova, Irina; Dmitrieva, Yulia

2015-05-14

The gastrointestinal (GI) microbiota differs between breast-fed and classic infant formula-fed infants. Breast milk is rich in prebiotic oligosaccharides (OS) and may also contain some probiotics, but scientific societies do not recommend the addition of prebiotic OS or probiotics to standard infant formula. Nevertheless, many infant formula companies often add one or the other or both. Different types of prebiotic OS are used in infant formula, including galacto-oligosaccharide, fructo-oligosaccharide, polydextrose and mixtures of these OS, but none adds human milk OS. There is evidence that the addition of prebiotics to infant formula brings the GI microbiota of formula-fed infants closer to that of breast-fed infants. Prebiotics change gut metabolic activity (by decreasing stool pH and increasing SCFA), have a bifidogenic effect and bring stool consistency and defecation frequency closer to those of breast-fed infants. Although there is only limited evidence that these changes in GI microbiota induce a significant clinical benefit for the immune system, interesting positive trends have been observed in some markers. Additionally, adverse effects are extremely seldom. Prebiotics are added to infant formula because breast milk contains human milk OS. Because most studies suggest a trend of beneficial effects and because these ingredients are very safe, prebiotics bring infant formula one step closer to the golden standard of breast milk.

Physiological Changes of Surface Membrane in Lactobacillus with Prebiotics.

PubMed

Pan, Mingfang; Kumaree, Kishore K; Shah, Nagendra P

2017-03-01

Synbiotics are always considered to be beneficial in healthy manipulation of gut environment; however, the purpose of this research was to investigate the dominance of synbiotic over the individual potential of probiotics and prebiotics. Four different types of prebiotics, fructo-oligosaccharides, raffinose, inulin, and cellobiose, were evaluated based on their varying degree of polymerization, combined each with 2 different Lactobacilli strains, including Lactobacillus paracasei 276 and Lactobacillus plantarum WCFS1. The effects of synbiotics combination on the surface structure were evaluated by analyzing auto-aggregation, membrane hydrophobicity, and adhesion to Caco-2 cells. Our results showed that both Lactobacilli exhibited significantly greater degree of attachment to Caco-2 cells (23.31% and 16.85%, respectively) when using cellobiose as a substrate than with other prebiotics (P < 0.05). Intestinal adhesion ability was in correlation with the percent of auto-aggregation, both Lactobacillus exhibited higher percent of auto-aggregation in cellobiose compared to other prebiotics. These behavioral changes in terms of attachment and auto-aggregation were further supported with the changes noticed from infrared spectra (FT-IR). © 2017 Institute of Food Technologists®.

Atmospheric production of glycolaldehyde under hazy prebiotic conditions.

PubMed

Harman, Chester E; Kasting, James F; Wolf, Eric T

2013-04-01

The early Earth's atmosphere, with extremely low levels of molecular oxygen and an appreciable abiotic flux of methane, could have been a source of organic compounds necessary for prebiotic chemistry. Here, we investigate the formation of a key RNA precursor, glycolaldehyde (2-hydroxyacetaldehyde, or GA) using a 1-dimensional photochemical model. Maximum atmospheric production of GA occurs when the CH4:CO2 ratio is close to 0.02. The total atmospheric production rate of GA remains small, only 1 × 10(7) mol yr(-1). Somewhat greater amounts of GA production, up to 2 × 10(8) mol yr(-1), could have been provided by the formose reaction or by direct delivery from space. Even with these additional production mechanisms, open ocean GA concentrations would have remained at or below ~1 μM, much smaller than the 1-2 M concentrations required for prebiotic synthesis routes like those proposed by Powner et al. (Nature 459:239-242, 2009). Additional production or concentration mechanisms for GA, or alternative formation mechanisms for RNA, are needed, if this was indeed how life originated on the early Earth.

Emergent Sources of Prebiotics: Seaweeds and Microalgae.

PubMed

de Jesus Raposo, Maria Filomena; de Morais, Alcina Maria Miranda Bernardo; de Morais, Rui Manuel Santos Costa

2016-01-28

In recent years, scientists have become aware that human microbiota, in general, and gut microbiota, in particular, play a major role in human health and diseases, such as obesity and diabetes, among others. A large number of evidence has come to light regarding the beneficial effects, either for the host or the gut microbiota, of some foods and food ingredients or biochemical compounds. Among these, the most promising seem to be polysaccharides (PS) or their derivatives, and they include the dietary fibers. Some of these PS can be found in seaweeds and microalgae, some being soluble fibers, such as alginates, fucoidans, carrageenans and exopolysaccharides, that are not fermented, at least not completely, by colonic microbiota. This review gives an overview of the importance of the dietary fibers, as well as the benefits of prebiotics, to human health. The potential of the PS from marine macro- and microalgae to act as prebiotics is discussed, and the different techniques to obtain oligosaccharides from PS are presented. The mechanisms of the benefits of fiber, in general, and the types and benefits of algal fibers in human health are highlighted. The findings of some recent studies that present the potential effects of prebiotics on animal models of algal biomass and their extracts, as well as oligo- and polysaccharides, are presented. In the future, the possibility of using prebiotics to modulate the microbiome, and, consequently, prevent certain human diseases is foreseen.

Emergent Sources of Prebiotics: Seaweeds and Microalgae

PubMed Central

de Jesus Raposo, Maria Filomena; de Morais, Alcina Maria Miranda Bernardo; de Morais, Rui Manuel Santos Costa

2016-01-01

In recent years, scientists have become aware that human microbiota, in general, and gut microbiota, in particular, play a major role in human health and diseases, such as obesity and diabetes, among others. A large number of evidence has come to light regarding the beneficial effects, either for the host or the gut microbiota, of some foods and food ingredients or biochemical compounds. Among these, the most promising seem to be polysaccharides (PS) or their derivatives, and they include the dietary fibers. Some of these PS can be found in seaweeds and microalgae, some being soluble fibers, such as alginates, fucoidans, carrageenans and exopolysaccharides, that are not fermented, at least not completely, by colonic microbiota. This review gives an overview of the importance of the dietary fibers, as well as the benefits of prebiotics, to human health. The potential of the PS from marine macro- and microalgae to act as prebiotics is discussed, and the different techniques to obtain oligosaccharides from PS are presented. The mechanisms of the benefits of fiber, in general, and the types and benefits of algal fibers in human health are highlighted. The findings of some recent studies that present the potential effects of prebiotics on animal models of algal biomass and their extracts, as well as oligo- and polysaccharides, are presented. In the future, the possibility of using prebiotics to modulate the microbiome, and, consequently, prevent certain human diseases is foreseen. PMID:26828501

The effect of prebiotics on production of antimicrobial compounds, resistance to growth at low pH and in the presence of bile, and adhesion of probiotic cells to intestinal mucus.

PubMed

Brink, M; Todorov, S D; Martin, J H; Senekal, M; Dicks, L M T

2006-04-01

Screening of five bile salt-resistant and low pH-tolerant lactic acid bacteria for inhibitory activity against lactic acid bacteria and bacterial strains isolated from the faeces of children with HIV/AIDS. Determining the effect of prebiotics and soy milk-base on cell viability and adhesion of cells to intestinal mucus. Lactobacillus plantarum 423, Lactobacillus casei LHS, Lactobacillus salivarius 241, Lactobacillus curvatus DF 38 and Pediococcus pentosaceus 34 produced the highest level of antimicrobial activity (12,800 AU ml(-1)) when grown in MRS broth supplemented with 2% (m/v) dextrose. Growth in the presence of Raftilose Synergy1, Raftilose L95 and Raftiline GR did not lead to increased levels of antimicrobial activity. Cells grown in the presence of Raftilose Synergy1 took longer to adhere to intestinal mucus, whilst cells grown in the absence of prebiotics showed a linear rate of binding. A broad range of gram-positive and gram-negative bacteria were inhibited. Dextrose stimulated the production of antimicrobial compounds. Adhesion to intestinal mucus did not increase with the addition of prebiotics. The strains may be incorporated in food supplements for HIV/AIDS patients suffering from gastro-intestinal disorders.

A low-carbohydrate/high-fat diet reduces blood pressure in spontaneously hypertensive rats without deleterious changes in insulin resistance.

PubMed

Bosse, John D; Lin, Han Yi; Sloan, Crystal; Zhang, Quan-Jiang; Abel, E Dale; Pereira, Troy J; Dolinsky, Vernon W; Symons, J David; Jalili, Thunder

2013-06-15

Previous studies reported that diets high in simple carbohydrates could increase blood pressure in rodents. We hypothesized that the converse, a low-carbohydrate/high-fat diet, might reduce blood pressure. Six-week-old spontaneously hypertensive rats (SHR; n = 54) and Wistar-Kyoto rats (WKY; n = 53, normotensive control) were fed either a control diet (C; 10% fat, 70% carbohydrate, 20% protein) or a low-carbohydrate/high-fat diet (HF; 20% carbohydrate, 60% fat, 20% protein). After 10 wk, SHR-HF had lower (P < 0.05) mean arterial pressure than SHR-C (148 ± 3 vs. 159 ± 3 mmHg) but a similar degree of cardiac hypertrophy (33.4 ± 0.4 vs. 33.1 ± 0.4 heart weight/tibia length, mg/mm). Mesenteric arteries and the entire aorta were used to assess vascular function and endothelial nitric oxide synthase (eNOS) signaling, respectively. Endothelium-dependent (acetylcholine) relaxation of mesenteric arteries was improved (P < 0.05) in SHR-HF vs. SHR-C, whereas contraction (potassium chloride, phenylephrine) was reduced (P < 0.05). Phosphorylation of eNOSSer1177 increased (P < 0.05) in arteries from SHR-HF vs. SHR-C. Plasma glucose, insulin, and homoeostatic model of insulin assessment were lower (P < 0.05) in SHR-HF vs. SHR-C, whereas peripheral insulin sensitivity (insulin tolerance test) was similar. After a 10-h fast, insulin stimulation (2 U/kg ip) increased (P < 0.05) phosphorylation of AktSer473 and S6 in heart and gastrocnemius similarly in SHR-C vs. SHR-HF. In conclusion, a low-carbohydrate/high-fat diet reduced blood pressure and improved arterial function in SHR without producing signs of insulin resistance or altering insulin-mediated signaling in the heart, skeletal muscle, or vasculature.

A low-carbohydrate/high-fat diet reduces blood pressure in spontaneously hypertensive rats without deleterious changes in insulin resistance

PubMed Central

Bosse, John D.; Lin, Han Yi; Sloan, Crystal; Zhang, Quan-Jiang; Abel, E. Dale; Pereira, Troy J.; Dolinsky, Vernon W.; Symons, J. David

2013-01-01

Previous studies reported that diets high in simple carbohydrates could increase blood pressure in rodents. We hypothesized that the converse, a low-carbohydrate/high-fat diet, might reduce blood pressure. Six-week-old spontaneously hypertensive rats (SHR; n = 54) and Wistar-Kyoto rats (WKY; n = 53, normotensive control) were fed either a control diet (C; 10% fat, 70% carbohydrate, 20% protein) or a low-carbohydrate/high-fat diet (HF; 20% carbohydrate, 60% fat, 20% protein). After 10 wk, SHR-HF had lower (P < 0.05) mean arterial pressure than SHR-C (148 ± 3 vs. 159 ± 3 mmHg) but a similar degree of cardiac hypertrophy (33.4 ± 0.4 vs. 33.1 ± 0.4 heart weight/tibia length, mg/mm). Mesenteric arteries and the entire aorta were used to assess vascular function and endothelial nitric oxide synthase (eNOS) signaling, respectively. Endothelium-dependent (acetylcholine) relaxation of mesenteric arteries was improved (P < 0.05) in SHR-HF vs. SHR-C, whereas contraction (potassium chloride, phenylephrine) was reduced (P < 0.05). Phosphorylation of eNOSSer1177 increased (P < 0.05) in arteries from SHR-HF vs. SHR-C. Plasma glucose, insulin, and homoeostatic model of insulin assessment were lower (P < 0.05) in SHR-HF vs. SHR-C, whereas peripheral insulin sensitivity (insulin tolerance test) was similar. After a 10-h fast, insulin stimulation (2 U/kg ip) increased (P < 0.05) phosphorylation of AktSer473 and S6 in heart and gastrocnemius similarly in SHR-C vs. SHR-HF. In conclusion, a low-carbohydrate/high-fat diet reduced blood pressure and improved arterial function in SHR without producing signs of insulin resistance or altering insulin-mediated signaling in the heart, skeletal muscle, or vasculature. PMID:23604708

Food-derived carbohydrates--structural complexity and functional diversity.

PubMed

Tharanathan, Rudrapatnam N

2002-01-01

Carbohydrates are biomolecules abundantly available in nature. They are found in bewildering types ranging from simple sugars through oligo- and polysaccharides to glycoconjugates and saccharide complexes, each exhibiting characteristic bio-physiological and/or nutritional functions both in in vivo and in vitro systems. For example, their presence or inclusion in food dictates the texture (body) and gives desirable customer appeal (satisfaction), or their inclusion in the diet offers beneficial effects of great therapeutic value. Thus, carbohydrates are integrally involved in a multitude of biological functions such as regulation of the immune system, cellular signaling (communication), cell malignancy, antiinfection responses, host-pathogen interactions, etc. If starch is considered the major energy storage carbohydrate, the gums/mucilages and other non-starch carbohydrates are of structural significance. The most investigated properties of starch are its gelatinization and melting behavior, especially during food processing. This has led to the development of the food polymer science approach, which has enabled a new interpretive and experimental frame work for the study of the plasticizing influence of simple molecules such as water, sugars, etc. on food systems that are kinetically constrained. Starch, although considered fully digestible, has been challenged, and starch is found to be partly indigestible in the GI tract of humans. This fraction of starch-resisting digestion in vivo is known as resistant starch (RS). The latter, due to its excellent fermentative capacity in the gut, especially yielding butyric acid is considered a new tool for the creation of fiber-rich foods, which are of nutraceutical importance. By a careful control of the processing conditions the content of RS, a man-made fiber, can be increased to as high as 30%. Arabinoxylans are the major endospermic cell wall polysaccharides of cereals. In wheat they are found complexed with ferulic

A randomized pilot trial of a moderate carbohydrate diet compared to a very low carbohydrate diet in overweight or obese individuals with type 2 diabetes mellitus or prediabetes.

PubMed

Saslow, Laura R; Kim, Sarah; Daubenmier, Jennifer J; Moskowitz, Judith T; Phinney, Stephen D; Goldman, Veronica; Murphy, Elizabeth J; Cox, Rachel M; Moran, Patricia; Hecht, Fredrick M

2014-01-01

We compared the effects of two diets on glycated hemoglobin (HbA1c) and other health-related outcomes in overweight or obese adults with type 2 diabetes or prediabetes (HbA1c>6%). We randomized participants to either a medium carbohydrate, low fat, calorie-restricted, carbohydrate counting diet (MCCR) consistent with guidelines from the American Diabetes Association (n = 18) or a very low carbohydrate, high fat, non calorie-restricted diet whose goal was to induce nutritional ketosis (LCK, n = 16). We excluded participants receiving insulin; 74% were taking oral diabetes medications. Groups met for 13 sessions over 3 months and were taught diet information and psychological skills to promote behavior change and maintenance. At 3 months, mean HbA1c level was unchanged from baseline in the MCCR diet group, while it decreased 0.6% in the LCK group; there was a significant between group difference in HbA1c change favoring the LCK group (-0.6%, 95% CI, -1.1% to -0.03%, p = 0.04). Forty-four percent of the LCK group discontinued one or more diabetes medications, compared to 11% of the MCCR group (p = 0.03); 31% discontinued sulfonylureas in the LCK group, compared to 5% in the MCCR group (p = 0.05). The LCK group lost 5.5 kg vs. 2.6 kg lost in MCCR group (p = 0.09). Our results suggest that a very low carbohydrate diet coupled with skills to promote behavior change may improve glycemic control in type 2 diabetes while allowing decreases in diabetes medications. This clinical trial was registered with ClinicalTrials.gov, number NCT01713764.