Dietary fibre content and nutrient claims relative to the faecal bulking efficacy of breakfast cereals

Fiber levels in laying quail diets

The objective of this work was to determine the effect of inclusion levels of dietary fiber in the Japanese quail diets. 480 Japanese quail were distributed in a completely randomized design, with 5 treatments and 12 replicates composed of 8 birds each. The treatments were constituted by five increasing levels of fiber in the diet: 2.78; 3.08; 3.38; 3.68; 3.98%. The parameters of productive performance, water consumption, egg quality, total lipids in the egg, excreta humidity, weight of digestive organs and intestinal morphology were evaluated. There was no significant effect of the use of different fiber levels on feed intake, egg production, viability, live weight, relative and absolute weight of gizzard, small intestine and cecum, and in excreta moisture of Japanese quais. Higher dietary fiber levels resulted in improvements in feed conversion per mass and per dozen eggs and higher water consumption. There was no significant difference for egg quality, except fot the color of the yolk where it was observed higher pigmentation of this structure with higher levels of fiber inclusion, and the lipid concentration in the buds was influenced in a quadratic manner. The inclusion of fiber promoted improvement in the villi of the duodenum and cecum.

Bacterial Cellulose Relieves Diphenoxylate-Induced Constipation in Rats

This study was to probe the effects of bacterial cellulose (BC) on diphenoxylate-induced constipation in rats. Administration with BC at 500 mg/kg of body weight in diphenoxylate-induced constipation rats distinctly improved the carmine propulsion rate (83.5 ± 5.2%), shortened the defecating time of the first red feces (249.0 ± 23.3 min), and increased the weight of carmine red feces within 5 h (2.7 ± 1.3 g). The levels of aquaporins (AQP-2, AQP-3, and AQP-4) and inhibitory neurotransmitters (nitric oxide, nitric oxide synthetase, vasoactive intestinal peptide, and arginine vasopressin) in the BC-treated groups reduced by 31.9-40.0% ( p < 0.01) and 21.1-67.7% ( p < 0.01) compared to those in the constipation group, respectively. However, the secretion of excitability neurotransmitters (substance P and motilin) in the BC-treated groups was increased by 20.0-39.9% ( p < 0.01). The activities of ATPases in the colon of constipation rats were significantly weakened by BC administration ( p < 0.01). Histological morphology of the colon showed that BC supplementation could effectively increase the length of villus cells and the thickness of colonic mucosa and muscle ( p < 0.01). Moreover, BC supplementation could protect colonic smooth muscle cells against apoptosis. All of the findings suggest that BC supplementation effectively relieves constipation in rats and BC would be used as a great promising dietary fiber for alleviating constipation.

Bioactivity of food peptides: biological response of rats to bovine milk whey peptides following acute exercise

Background: Several physiologically beneficial effects of consuming a whey protein hydrolysate (WPH) have been attributed to the greater availability of bioactive peptides.

Aims: The aim was to investigate the effect of four branched-chain amino acid- (BCAA-)containing dipeptides, present in WPH, on immune modulation, stimulation of HSP expression, muscle protein synthesis, glycogen content, satiety signals and the impact of these peptides on the plasma free amino acid profiles.

Methods: The animals were divided in groups: control (rest, without gavage), vehicle (water), L-isoleucyl-L-leucine (lle-Leu), L-leucyl-L-isoleucine (Leu-lle), L-valyl-Lleucine (Val-Leu), L-leucyl-L-valine (Leu-Val) and WPH. All animals were submitted to acute exercise, except for control.

Results: lle-Leu stimulated immune response, hepatic and muscle glycogen and HSP60 expression, whereas Leu-Val enhanced HSP90 expression. All dipeptides reduced glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide, no changes were observed on leptin. All peptides inhibited NF-kB expression. The plasma amino acid time-course showed peptide-specific and isomer-specific metabolic features, including increases of the BCAAs.

Conclusion: The data indicate that lle-Leu was effective to attenuate immune-suppression exercise-induced, promoted glycogen content and stimulated anti-stress effect (HSP). Furthermore, Leu-Val increased HSP90, p-4EBP1, p-mTOR and p-AMPK expression. The data suggest the involvement of these peptides in various beneficial functions of WPH consumption.

Virtual food components: functional food effects expressed as food components

BACKGROUND

The ability to communicate food benefits is essential for the successful development of functional foods and their role in improving public health. However, the functional efficacy of foods often cannot be represented by food composition. The concept of virtual food components (VFCs)-food data that express health-related effects, properties or functions of foods in the format of food components-is therefore proposed.

OBJECTIVE

To develop protocols for designing VFC data sets that communicate functional efficacies of foods to end users, in order to facilitate evidence-based food choice, and allow data management systems to provide a more complete description of nutritional effects of foods than has been possible with values for actual food components alone.

METHOD

A framework within which to develop VFCs was constructed, linking food choice to health end points. It involves scientific validation, generation of relative indices, their translation into a meaningful language based on equivalents to known and understood reference foods, followed by data consolidation and ecological validation. Criteria used to evaluate VFCs were importance, independence, validity, accuracy, robustness, sensitivity, linearity/additivity, relevance, comprehensiveness, acquirability, completeness, meaningfulness, acceptability and safety. The developmental framework and evaluative criteria were applied to glycaemic glucose equivalents (GGE), a VFC representing postprandial glycaemia, and to wheat bran equivalents for faecal bulk (WBE(fb)), a VFC representing faecal bulking efficacy.

RESULTS

VFCs were used to identify foods according to health-related effects that cannot be accurately predicted from food composition data, and were used in a nutrition management system to concurrently show nutrient intake and physiological effects in the same units. The proposed evaluative criteria identified points requiring further research, and showed that lack of integrity-tested VFC data is an immediate challenge.

CONCLUSION

VFCs are a means of communicating relative functional efficacy of foods as a continuous variable, and provide end users with a more accurate and complete view of the health effects of foods than can be provided by health claims or food composition data alone.

Adequate intake values for dietary fibre based on faecal bulking indexes of 66 foods

OBJECTIVE

To determine an adequate daily intake value for dietary fibre (AIdf) based on faecal bulking indexes (FBIs) for 66 foods of known total dietary fibre (TDF) content.

DESIGN

FBIs of 66 foods were measured and expressed as wheat bran equivalents (WBEfb) per 100 g of food. A daily WBEfb requirement for humans was calculated from faecal bulk generated per gram of wheat bran TDF in humans, using a critical faecal mass of 200 g/day for protection against large bowel disease. TDF content was regressed against WBEfb content for all 66 foods assayed, and an AIdf value obtained by substituting the calculated human WBEfb requirement into the regression equation.

METHOD

FBI was measured using a validated rat assay, with eight large (400+/-50 g) rats per group, preadapted to dietary fibre, and fed adequate restricted diets containing test foods at inclusion rates consistent with human intakes. The critical faecal mass was based on epidemiological studies, and the faecal bulk generated per gram of wheat bran TDF was the mean of 27 published values.

RESULTS

WBEfb requirements for humans were calculated to be 90 g/day, corresponding to a faecal output of 200 g/day. The regression equation relating WBEfb measured in the FBI assay to TDF in all 66 foods was TDF=0.491WBEfb + 3.19, R2=0.81 Substituting the human WBEfb requirement of 90 g into the regression equation gave an AIdf value of 40.9 g TDF/day.

CONCLUSION

The AIdf value of 40.9 g TDF/day based on faecal bulking supports the AIdf of 38 g TDF/day recently set by the Institute of Medicine (USA), for young men, based on protection against heart disease. The AIdf value is obtained from the relation between the effects of foods and their content of mixed function, plant cell wall dietary fibres within the food matrices, and should not be used to guide intakes of extrinsic functional polysaccharides.