The link between dietary fibre and human health

Consumption of the Soluble Dietary Fibre Complex PolyGlycopleX(®) Reduces Glycaemia and Increases Satiety of a Standard Meal Postprandially

The effect of consumption of PolyGlycopleX^® (PGX^®) was compared to wheat dextrin (WD) in combination with a standard meal, on postprandial satiety and glycaemia in a double-blind, randomised crossover trial, of 14 healthy subjects trained as a satiety panel. At each of six two-hour satiety sessions, subjects consumed one of three different test meals on two separate occasions. The test meals were: a standard meal plus 5 g PGX; a standard meal plus 4.5 g of PGX as softgels; and a standard meal plus 5 g of WD. Subjects recorded fullness using a labelled magnitude scale at 0, 15, 30, 45, 60, 90, and 120 min and the total area under the curve (AUC), mean fullness vs. time was calculated. The meals with PGX (in granular and softgel form) gave higher satiety (AUC) (477 ± 121 and 454 ± 242 cm·min), than the meal with WD (215 ± 261 cm·min) (p < 0.001). Subjects had blood glucose levels measured after the meals with PGX (granules) and WD. Glucose response (AUC) was significantly lower (p < 0.001) after the PGX meal than for the WD meal.  The high viscosity reported for PGX is a likely mechanism behind the significant satiety and blood glucose modulating effects observed in this study.

Molecular structure, chemical properties and biological activities of Pinto bean pod polysaccharide

Pinto bean pod polysaccharide (PBPP) was successfully extracted with yield of 38.5g/100g and the PBPP gave total carbohydrate and uronic acid contents of 286.2mg maltose equivalent/g and 374.3mgGal/g, respectively. The Mw of PBPP was 270.6kDa with intrinsic viscosity of 0.262dm(3)/g, which composed of mannose (2.5%), galacturonic acid (15.0%), rhamnose (4.0%), glucose (9.0%), galactose (62.2%), xylose (2.9%) and arabinose (4.3%) with trace amount of ribose and fucose. The result suggested that PBPP has a spherical conformation with a highly branched structure. Fourier Transform Infrared analysis showed that PBPP has a similar structure as commercial pectin with an esterification degree of 59.9%, whereas scanning electron microscopy study showed that the crude polysaccharide formed a thin layer of film that was made of multiple micro strands of fibre. PBPP exhibited substantial free radical scavenging activity (7.7%), metal reducing capability (2.04mmol/dm(3)) and α-amylase inhibitory activity (97.6%) at a total amount of 1mg. PBPP also exhibited high water- and oil-holding capacities (3.6g/g and 2.8g/g, respectively). At a low concentration, PBPP exhibited emulsifying activity of 39.6% with stability of 38.6%. Apart from that, PBPP was able to show thickening capability at low concentration (0.005kg/dm(3)).

Looking Beyond the Terrestrial: The Potential of Seaweed Derived Bioactives to Treat Non-Communicable Diseases

Seaweeds are a large and diverse group of marine organisms that are commonly found in the maritime regions of the world. They are an excellent source of biologically active secondary metabolites and have been shown to exhibit a wide range of therapeutic properties, including anti-cancer, anti-oxidant, anti-inflammatory and anti-diabetic activities. Several Asian cultures have a strong tradition of using different varieties of seaweed extensively in cooking as well as in herbal medicines preparations. As such, seaweeds have been used to treat a wide variety of health conditions such as cancer, digestive problems, and renal disorders. Today, increasing numbers of people are adopting a "westernised lifestyle" characterised by low levels of physical exercise and excessive calorific and saturated fat intake. This has led to an increase in numbers of chronic Non-communicable diseases (NCDs) such as cancer, cardiovascular disease, and diabetes mellitus, being reported. Recently, NCDs have replaced communicable infectious diseases as the number one cause of human mortality. Current medical treatments for NCDs rely mainly on drugs that have been obtained from the terrestrial regions of the world, with the oceans and seas remaining largely an untapped reservoir for exploration. This review focuses on the potential of using seaweed derived bioactives including polysaccharides, antioxidants and fatty acids, amongst others, to treat chronic NCDs such as cancer, cardiovascular disease and diabetes mellitus.

Effect of the particle size of cellulose from sweet potato residues on lipid metabolism and cecal conditions in ovariectomized rats

This study aims to examine the effect of the particle size of cellulose from sweet potato residues on lipid metabolism and cecal conditions in ovariectomized rats. Forty mature female Wistar rats were divided into five groups. The sham-operated group was used as the sham control. The other four groups were double-ovariectomized and assigned to the model, ordinary cellulose (100 g kg(-1) diet), microcrystalline cellulose (100 g kg(-1) diet), and cellulose nanocrystal (100 g kg(-1) diet) groups. As the cellulose particle size decreased, the body weight gain and food intake were decreased. The plasma lipids and hepatic lipids were decreased. In addition, the mRNA levels of cholesterol 7α-hydroxylase, farnesoid X receptor, and 3-hydroxy-3-methylglutaryl coenzyme A reductase were decreased, whereas those of ileal apical sodium-dependent bile acid transporter and intestinal bile acid binding protein were increased. The cecum weight, cecum content, and short-chain fatty acid concentration and the amount of total bile acids in the small intestinal content, as well as the bile acids and neutral steroids in fecal excretion, were increased. These results indicate that as the particle size decreased, cellulose was more effective in preventing ovarian hormone deficiency-induced hyperlipidemia and in improving intestinal health.

Glycemic index and microstructure analysis of a newly developed fiber enriched cookie

A diet with a high glycemic index (GI) is associated with an elevated risk for obesity or type 2 diabetes.

Physicochemical properties of cookies enriched with xylooligosaccharides

The growing commercial importance of xylooligosaccharides is based on their beneficial health properties, particularly their ability to stimulate the growth and activity of intestinal bacteria such as Bifidobacterium and Lactobacillus species. Xylooligosaccharides are less sweet, acid, and heat stable, with low recommended levels of intake compared to other oligosaccharides. In view of the consumer demand for foods with low sugar, low fat, and high fiber contents, they are suitable for incorporation into bakery products. In this study, we have developed wheat-based cookies incorporated with xylooligosaccharides at 5%, 10%, and 15% levels. The nutritive value and physicochemical properties of the cookies changed with xylooligosaccharides incorporation; both crude fiber and dietary fiber contents increased by 14% and 35%, respectively, in the enriched cookies. The moisture levels increased with increase in the percentage of xylooligosaccharides incorporated. Cookies with 5% xylooligosaccharides were found most acceptable, although the color was slightly darker compared to the control, while cookies with 10% and 15% xylooligosaccharides were softer and darker and therefore less acceptable. Enrichment with xylooligosaccharides at 5% provided a product stable for 21 days at room temperature (25 ± 2℃). The storage stability of cookies with higher levels of xylooligosaccharides was less than the 5% xylooligosaccharides cookies and control. The retention of the prebiotic xylooligosaccharides in the products was relatively high (74%).

Bioactive Compounds Found in Brazilian Cerrado Fruits

Functional foods include any natural product that presents health-promoting effects, thereby reducing the risk of chronic diseases. Cerrado fruits are considered a source of bioactive substances, mainly phenolic compounds, making them important functional foods. Despite this, the losses of natural vegetation in the Cerrado are progressive. Hence, the knowledge propagation about the importance of the species found in Cerrado could contribute to the preservation of this biome. This review provides information about Cerrado fruits and highlights the structures and pharmacologic potential of functional compounds found in these fruits. Compounds detected in Caryocar brasiliense Camb. (pequi), Dipteryx alata Vog. (baru), Eugenia dysenterica DC. (cagaita), Eugenia uniflora L. (pitanga), Genipa americana L. (jenipapo), Hancornia speciosa Gomes (mangaba), Mauritia flexuosa L.f. (buriti), Myrciaria cauliflora (DC) Berg (jabuticaba), Psidiumguajava L. (goiaba), Psidium spp. (araçá), Solanum lycocarpum St. Hill (lobeira), Spondias mombin L. (cajá), Annona crassiflora Mart. (araticum), among others are reported here.

Digestibilidade do amido in vitro e valor calórico dos grupos de farinhas de mandioca brasileiras

Resumo A preferência cultural do brasileiro originou grupos e subclassificações da farinha de mandioca em função dos processos adotados. Diferenças de processamento das farinhas de mandioca podem afetar a digestibilidade do amido, assim seu teor calórico foi investigado. Foram selecionadas cinco amostras dos três grupos de farinha de mandioca: Seca, Bijusada e D’água. O teste de digestibilidade do amido foi realizado in vitro, incubando a suspensão de farinha com amilase (alfa-1,4-glucano-4-glucanohidrolase) em condições de temperatura e pH que simulam a digestão humana. Alíquotas foram coletadas a cada 15 minutos, durante 1 hora e o teor de glicose liberado foi expresso em calorias rapidamente disponíveis. Os resultados mostraram que o valor calórico de todas as amostras de farinha de mandioca permaneceu ao redor de 300 kcal. 100 g–1. Considerando a cinética de liberação em função do tempo e do grupo, as amostras de farinha de mandioca diferiram. As farinhas de mandioca com menor granulometria, Biju Fina e Furnas (Grupo Bijusada e Seca), apresentaram rápida liberação de açúcares aos 15 minutos, variando de 110 a 215 kcal. 100 g–1, respectivamente. A farinha de mandioca Fina (Grupo Seca) teve liberação uniforme de glicose durante a avaliação. O açúcar liberado pelas farinhas de mandioca com maior granulometria, Biju Grossa e D’água (Grupo Bijusada e D’água), apresentaram dois picos de liberação: o primeiro aos 15 minutos de incubação (liberando 84,2 e 120,48 kcal. 100 g–1, respectivamente); enquanto o segundo pico para a amostra Biju Grossa ocorreu aos 45 minutos (112 kcal. 100 g–1), para a farinha D’água foi após 60 minutos (67,88 kcal. 100 g–1). Pela avaliação microscópica foi observada a presença de grânulos de amido residuais não hidrolisados, variando de 2,42 a 17,85%. Os resultados mostraram que o valor calórico das farinhas de mandioca variou em função do processamento, que afetou a granulometria da farinha, que por sua vez influenciou a gelatinização do amido, fatores esses que determinaram a intensidade da ação das enzimas na liberação de glicose.

Cost-of-illness analysis reveals potential healthcare savings with reductions in type 2 diabetes and cardiovascular disease following recommended intakes of dietary fiber in Canada

BACKGROUND

Type 2 diabetes (T2D) and cardiovascular disease (CVD) are leading causes of mortality and two of the most costly diet-related ailments worldwide. Consumption of fiber-rich diets has been repeatedly associated with favorable impacts on these co-epidemics, however, the healthcare cost-related economic value of altered dietary fiber intakes remains poorly understood. In this study, we estimated the annual cost savings accruing to the Canadian healthcare system in association with reductions in T2D and CVD rates, separately, following increased intakes of dietary fiber by adults.

METHODS

A three-step cost-of-illness analysis was conducted to identify the percentage of individuals expected to consume fiber-rich diets in Canada, estimate increased fiber intakes in relation to T2D and CVD reduction rates, and independently assess the potential annual savings in healthcare costs associated with the reductions in rates of these two epidemics. The economic model employed a sensitivity analysis of four scenarios (universal, optimistic, pessimistic, and very pessimistic) to cover a range of assumptions within each step.

RESULTS

Non-trivial healthcare and related savings of CAD$35.9-$718.8 million in T2D costs and CAD$64.8 million-$1.3 billion in CVD costs were calculated under a scenario where cereal fiber was used to increase current intakes of dietary fiber to the recommended levels of 38 g per day for men and 25 g per day for women. Each 1 g per day increase in fiber consumption resulted in annual CAD$2.6 to $51.1 million savings for T2D and $4.6 to $92.1 million savings for CVD.

CONCLUSION

Findings of this analysis shed light on the economic value of optimal dietary fiber intakes. Strategies to increase consumers' general knowledge of the recommended intakes of dietary fiber, as part of healthy diet, and to facilitate stakeholder synergy are warranted to enable better management of healthcare and related costs associated with T2D and CVD in Canada.

Apples and cardiovascular health--is the gut microbiota a core consideration?

There is now considerable scientific evidence that a diet rich in fruits and vegetables can improve human health and protect against chronic diseases. However, it is not clear whether different fruits and vegetables have distinct beneficial effects. Apples are among the most frequently consumed fruits and a rich source of polyphenols and fiber. A major proportion of the bioactive components in apples, including the high molecular weight polyphenols, escape absorption in the upper gastrointestinal tract and reach the large intestine relatively intact. There, they can be converted by the colonic microbiota to bioavailable and biologically active compounds with systemic effects, in addition to modulating microbial composition. Epidemiological studies have identified associations between frequent apple consumption and reduced risk of chronic diseases such as cardiovascular disease. Human and animal intervention studies demonstrate beneficial effects on lipid metabolism, vascular function and inflammation but only a few studies have attempted to link these mechanistically with the gut microbiota. This review will focus on the reciprocal interaction between apple components and the gut microbiota, the potential link to cardiovascular health and the possible mechanisms of action.

Novel trends in development of dietary fiber rich meat products-a critical review

Meat and meat products are generally recognized as good sources of high biological value proteins, fat-soluble vitamins, minerals, trace elements and bioactive compounds. Changes in socioeconomic factors in recent years have increased the consumer's preference for ready to eat foods including meat products. The processing of meat and meat products leads to generation of many functional compounds beneficial to human health but most of those foods are rich in fat, added salts but deficient in complex carbohydrates like dietary fiber and pose a health hazard that somehow is proved to be a predisposing factor for cardiovascular diseases, colon cancer, obesity including diabetes mellitus. With increasing consciousness among consumers about their nutrition and well being, there is a growing concern over nutritional diseases of affluence. Therefore an increase in dietary fiber inclusion in daily diet has been recommended. For adults, the recommended acceptable intakes of dietary fiber are 28-36 g/day, 70-80 % of which must be insoluble fiber. The insoluble fraction of dietary fiber has been related to intestinal regulation whereas soluble fiber is associated with decrease in cholesterol level and absorption of intestinal glucose. So incorporation of dietary fibers from different sources in meat products would help to enhance their desirability. Dietary fiber sources are generally agricultural byproducts that are comparatively cheap and incorporation in meat products reduces its overall cost. Whole grains and cereal brans are the rich source of insoluble fiber and pectins, gums, starch and other storage polysaccharides have high content of the soluble fraction. With this background, the effect of various dietary fibers on the quality attributes of meat and meat products with its physiological role has been reviewed here.

Effects of various fibre-rich extracts on cholesterol binding capacity during in vitro digestion of pork patties

Intake of foods containing high levels of cholesterol harms human health, and an increase in the intake of dietary fibre (DF) may mitigate these negative effects.

Correlating the structure and in vitro digestion viscosities of different pectin fibers to in vivo human satiety

The effects of a simulated in vitro digestion on the viscosity of orange juice with added high methoxyl (HM), low methoxyl (LM), and low methoxyl amidated (LMA) pectins were examined in conjunction with a human satiety study with healthy men (n=10) and women (n=15). Orange juice solutions were formulated to be either low (0.039±0.007 Pa s) or high viscosity (0.14±0.035 Pa s). The apparent viscosities after an in vitro digestion simulating the gastric and small intestinal phases in the presence of hydrolytic enzymes and bile salts were recorded at 10 and 50 s⁻¹. The viscosity induced by LM pectin increased considerably after the gastric phase whereas samples with all pectin types showed considerable reductions in viscosity, compared to initial apparent viscosity, after the small intestinal phase. For satiety testing, the orange juice solutions were consumed with a standardized breakfast meal after a 12 h overnight fast. Self-reported visual analogue scale (VAS) measurements of Hunger, Fullness, Satisfaction and Prospective Food Intake were obtained at fasting, after consumption of the breakfast and for the subsequent 3 h. The LM low and high viscosity pectin beverages were associated with the greatest effects on subjective ratings of satiety. The HM low and high viscosity pectin beverages had lower but significant effects on satiety, while LMA pectin had no effect. There was not a strong correlation between apparent viscosity of in vitro digested beverages and in vivo satiety scores. Thus, in this study, fiber-induced satiety could not be fully explained by digestate viscosity alone although gastric-phase viscosity may have played a significant role.

The effects of beta-glucan rich oat bread on serum nitric oxide and vascular endothelial function in patients with hypercholesterolemia

INTRODUCTION

Oats are high in soluble fibers and effective in reducing the risk of cardiovascular diseases (CVD). We assessed the effects of beta-glucan from oat bran on serum nitric oxide (NO) endothelial function in patients with hypercholesterolemia.

METHOD

Sixty hypercholesterolemic patients were randomly divided to receive an experimental bread rich in beta-glucan from oat bran (intervention) or bread rich in wheat fiber (control) for four weeks. All subjects had the same diet for two-week baseline period and hypocaloric diet for four weeks of intervention. Serum NO concentration and flow-mediated dilation (FMD) were determined before and after the experiment.

RESULTS

Mean age of the participants was 51.1 ± 9.3 years and 65% (n = 39) were female. After intervention, serum NO concentration increased by 50.2 ± 19.8 μmol/lit in the intervention group (P = 0.017), but no change was observed in the control group (17.5 ± 27.5 μmol/lit; P = 0.530). No change of FMD was observed in the intervention (0.48 ± 0.78%; P = 0.546) or in the control group (0.59 ± 0.92%; P = 0.533).

CONCLUSION

Consumption of oat bread for four weeks increases serum NO concentration but has no effect on FMD. Further studies are warranted in this regard.

Impact of micronized starfruit (Averrhoa carambola L.) fiber concentrate on lipid metabolism in mice

The objective of this study was to evaluate the effect of micronized insoluble fiber from starfruit bagasse as an ingredient of a functional food (FF) or as micronized insoluble fiber-rich fraction (IFRF) and its effects in vivo on lipids metabolism in a murine model. Experimental animals were divided in four isoproteic (15.8%) treatments differing on the fiber and cholesterol level used. The micronized IFRF particle size ranged from 37.5 to 149 μm. Treatments with added IFRF and those including the FF lowered serum triacylglycerols, total cholesterol (TC), high-density lipoproteins (HDL), and low-density lipoproteins (LDL) concentrations (IFRF: 14.2, 25.4, 55.06, and 12.18%, respectively; FF: 30.18, 39.47, 35.11, and 43.18%, respectively). IFRF produced the overall highest serum hypolipidemic effect and prevented the development of non-alcoholic fatty liver. Both the IFRF and the FF exhibited hypolipidemic effects that suggest a potential role of starfruit insoluble fiber as a component of FFs aimed against cardiovascular diseases.

Consuming a mixed diet enriched with lupin protein beneficially affects plasma lipids in hypercholesterolemic subjects: a randomized controlled trial

BACKGROUND & AIMS

The objectives of this study were to assess whether 25 g/d lupin protein, integrated into a mixed diet, might affect cardiovascular risk factors and whether l-arginine was responsible for these effects.

METHODS

Seventy-two hypercholesterolemic subjects participated in the randomized, controlled, double-blind three-phase crossover study. They were assigned to three diets with 25 g/d lupin protein (LP), milk protein (MP) or milk protein plus 1.6 g/d arginine (MPA) each for 28 d in a random order interrupted by 6-week washout periods. Lupin protein and the comparator milk protein were incorporated into complex food products (bread, roll, sausage, and vegetarian spread). Arginine was administered via capsules. Sixty-eight subjects were included in final analyses.

RESULTS

Compared with MP, LDL cholesterol was significantly lower after LP. Compared with MP and MPA, homocysteine was significantly lower after LP. Compared with baseline, concentrations of total, LDL, and HDL cholesterol significantly decreased after LP and MPA. Triacylglycerols and uric acid significantly decreased after LP. The relative changes in total and LDL cholesterol were significantly greater for subjects with severe hypercholesterolemia (>6.6 mmol/L) than those with moderate hypercholesterolemia (5.2-6.6 mmol/L).

CONCLUSIONS

The present study showed for the first time that incorporation of 25 g/d of lupin protein into a variety of complex food products lowers total and LDL cholesterol, triacylglycerols, homocysteine, and uric acid in hypercholesterolemic subjects. The hypocholesterolemic effect is stronger in subjects with severe hypercholesterolemia. Arginine might be responsible for some, but not all of the beneficial effects of lupin protein. This trial was registered at http://clinicaltrials.gov (study ID number NCT01598649).

Influence of Wheat-Milled Products and Their Additive Blends on Pasta Dough Rheological, Microstructure, and Product Quality Characteristics

This study is aimed to assess the suitability of T. aestivum wheat milled products and its combinations with T. durum semolina with additives such as ascorbic acid, vital gluten and HPMC (Hydroxypropyl methyl cellulose) for pasta processing quality characteristics such as pasta dough rheology, microstructure, cooking quality, and sensory evaluation. Rheological studies showed maximum dough stability in Comb1 (T. aestivum wheat flour and semolina). Colour and cooking quality of Comb2 (T. durum semolina and T. aestivum wheat flour) and Comb3 (T. aestivum wheat semolina and T. durum semolina) were comparable with control. Pasting results indicated that T. aestivum semolina gave the lowest onset gelatinization temperature (66.9°C) but the highest peak viscosity (1.053 BU). Starch release was maximum in Comb1 (53.45%) when compared with control (44.9%) as also proved by microstructure studies. Firmness was seen to be slightly high in Comb3 (2.430 N) when compared with control (2.304 N), and sensory evaluations were also in the acceptable range for the same. The present study concludes that Comb3 comprising 50% T. durum semolina and 50% T. aestivum refined wheat flour with additives would be optimal alternate for 100% T. durum semolina for production of financially viable pasta.

Development of a freeze-dried mixture of Nile tilapia (Oreochromis niloticus) croquette using a GA-based multiobjective optimisation

BACKGROUND

The mechanically separated meat (MSM) of Nile tilapia is an example of a by-product that can be used in the development of new foods. The aim of this study was to optimise the mixture of different flours in the development of a freeze-dried mixture of fish croquette using Nile tilapia MSM. Flavour, texture and overall acceptance of seven formulations were evaluated by an acceptance test. A genetic algorithm (GA) with desirability functions was combined with a multiobjective optimisation of the response surface models.

RESULTS

The combination of flours was chosen to minimise cost and maximise overall acceptance and fibre content. Overall acceptance showed a statistically significant correlation (P ≤ 0.05) with flavour (r = 0.67) and texture (r = 0.61). The GA-based approach indicated that the highest overall acceptance was obtained when using wheat and rye flours in equal parts. This formulation had an overall acceptance of 7.52, a fibre content of 11.50 g kg⁻¹ and a cost of US$2.21/kg. After 24 h of freeze-drying, the water activity of the mixture was 0.11.

CONCLUSION

The GA-based approach was able to optimise the croquette formulation. The freeze-drying process contributed to the development of a value-added product with high quality and long shelf-life.

Solvent optimization extraction of antioxidants from foxtail millet species' insoluble fibers and their free radical scavenging properties

In this study, water and 80% of four organic solvents were employed to optimize the extraction of antioxidants from two species of foxtail millet's insoluble fibers under the same temperature, time, and solid/solvent ratio. The results showed that the acetone was able to extract the maximum amount of antioxidants (2.32 mg/g fiber for white specie and 3.86 mg/g fiber for yellow specie) followed by methanol and propanol from both samples. The neutral and the ethanol on the other hand extracted small amount of the antioxidants from the two fiber materials. While considerable level of Total Polyphenols Content (TPC) was recorded in both the water and the organic solvents' extracts, only traces of Total Flavonoid content (TFC) were observed in water, methanol and ethanol extracts. Propanol and acetone extracts was negative to the TFC test. The potency of both white and yellow foxtail millets' insoluble fibers antioxidant extracts was investigated using five different in vitro tests. It was realized that there was a variation in their capacities to quench DPPH and ABTS(+) radicals for the time running of 0-60 min. The samples from the yellow cereal exhibited high inhibition capacity against ABTS(+). No correlation was observed between TPC and radical scavenging capacities for DPPH and ABTS(+). In general, the yellow species contained more antioxidants in comparison with the white one and this accounted for its high antioxidant activity.

Plants, diet, and health

Chronic disease is a major social challenge of the twenty-first century. In this review, we examine the evidence for discordance between modern diets and those on which humankind evolved as the cause of the increasing incidence of chronic diseases, and the evidence supporting consumption of plant foods as a way to reduce the risk of chronic disease. We also examine the evidence for avoiding certain components of plant-based foods that are enriched in Western diets, and review the mechanisms by which different phytonutrients are thought to reduce the risk of chronic disease. This body of evidence strongly suggests that consuming more fruits and vegetables could contribute both to medical nutrition therapies, as part of a package of treatments for conditions like type 2 diabetes, heart disease, cancer, and obesity, and to the prevention of these diseases. Plant science should be directed toward improving the quality of plant-based foods by building on our improved understanding of the complex relationships between plants, our diet, and our health.