Dietary Fiber Fractions Research Articles

Effects of acid, alkaline and enzymatic extraction methods on functional, structural and antioxidant properties of dietary fiber fractions from quince (Cydonia oblonga Miller)

In this study, quince soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) were obtained by acid extraction, enzyme extraction and alkaline extraction methods. The acid extracted DF displayed higher results compared to enzyme and alkaline extraction methods in terms of water holding capacity (15.97 g/g SDF), oil holding capacity (1.05 g/g SDF) and nitrite ion adsorption capacity (92.83 mg/g SDF). The antioxidant activity and phenolic content of acid extracted IDF were significantly higher than the other quince DFs. In addition, quince DFs exhibited in vitro hypoglycaemic activity, exhibiting high glucose adsorption capacity (237 mg/g) and α-amylase inhibition activity (82 %). Similarly, acid extracted SDF of quince showed in vitro hypolipidemic activity, with cholesterol adsorption capacity of 155 mg/g and lipase inhibition activity of 36 %. The structures and thermal properties of quince DFs were characterized by FT-IR and TGA. Quince DFs with high functional properties might be suitable agents for functional food formulations, such as meat products, low-calorie fruit bars, flour mixtures, etc.

PSII-27 Dietary fiber fractions supplementation modulates pro-inflammatory cytokines, hindgut ammonia-nitrogen concentration, and diarrhea severity of nursery pigs

Abstract Dietary fiber may functionally modulate the intestinal health of pigs depending on the content of dietary fiber fraction (DFF). The objective of this study was to investigate the effects of DFF based on soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) ratio on growth performance, blood parameters, hindgut ammonia-nitrogen concentrations, and diarrhea severity (fecal consistency score, FCS) of nursery pigs. Mixed-sex pigs (n = 200) with an average body weight (BW) of 7.56 ± 0.86 kg were randomly assigned to 1 of 5 dietary treatments in a randomized complete block design, with 5 pigs per pen and 8 pens per treatment. Pigs were fed a basal diet (BD, containing 8.80% IDF and 0.70% SDF), or the BD diet supplemented with dietary fiber to provide an additional 2% DFF to provide SDF and IDF, from inulin and lignocellulose, respectively, in ratios of 1:1 (DFF1), 1:3 (DFF2), 1:5 (DFF3), and 1:7 (DFF4) for 28 d. Overall, there were no dietary effects on ADFI, ADG, and F:G (P > 0.05). Compared with the BD diet, there was no overall effect of DFF on blood parameters, except for reduced plasma interleukin (IL) -6 and IL-1β concentrations (P < 0.05). Plasma IL-6 was reduced in DFF1 by 20.1%, while plasma IL-1β was reduced in DFF2, DFF3, and DFF4 by average 20% (P < 0.05). Decreasing SDF:IDF ratio increased plasma urea nitrogen (P < 0.05) and tended to decrease plasma myeloperoxidase (P < 0.10) in a quadratic manner. Amongst all treatments, pigs fed DFF1 or DFF2 diet had the least plasma content of superoxide dismutase while pigs fed DFF3 had the greatest (P < 0.05). Pigs fed DFF, regardless of SDF:IDF ratio, had reduced cecal and colonic ammonia-nitrogen compared with BD (P < 0.01). Overall, FCS was reduced by DFF compared with BD (P < 0.001). Decreasing SDF:IDF ratio reduced FCS in a quadratic manner (P < 0.05). The results indicate that 2% DFF supplementation with inulin and lignocellulose, regardless of the SDF:IDF, modulated pro-inflammatory cytokines, hindgut ammonia-nitrogen concentration, and diarrhea severity in nursery pigs.

Effect of Carbohydrase Treatment on the Dietary Fibers and Bioactive Compounds of Cocoa Bean Shells (CBSs).

Cocoa bean shells (CBSs) are a byproduct of the chocolate production process, representing the external layer of the cocoa bean. CBSs exhibit many interesting chemical and nutritional characteristics resulting in a very rich content of dietary fiber (DF) and antioxidant compounds such as phenolic acids and flavan-3-ols. The DF fraction of CBSs is notably rich in soluble dietary fibers (SDFs), which may be associated with fermentability and prebiotic properties. The objective of this study was the valorization of CBSs through enzymatic treatments, thereby increasing the solubility of DF and potentially augmenting fermentability. CBSs were treated both raw and defatted. Three sets of carbohydrases were used in order to impact the dietary fiber profile. Cellulase, xylanase, pectinase and their combinations were used to perform enzymatic treatments. The application of cellulase, xylanase and a combination of both enzymes proved effective in achieving a high SDF destructuring of the insoluble dietary fiber (IDF) fraction in both defatted and raw CBSs. Notably, the SDF/IDF ratio was significantly elevated in the enzymatically hydrolyzed samples (1.13-1.33) compared to the untreated CBSs (0.33). Furthermore, the various treatments did not affect the antioxidant activity or the content of the main bioactive compounds. These results provide a foundation for new opportunities in the biovalorization of CBSs through green techniques for a range of potential industrial applications in the food and nutraceutical sectors.

Chemical Composition and Nutritive Value of Sea Buckthorn Leaves.

Sea buckthorn leaves (SBT_LVs) form notable by-product during harvesting and post-harvest management of the berries. It is already known that sea buckthorn berries are important for their chemical composition and based on this, they occupy a wide field in nutrition. SBT_LVs also have a rich chemical composition, like the berries. The aim of this study was to describe these by-products in the context of protein and complex carbohydrates-dietary fiber fractions, including qualitative and quantitative composition of amino acids. Proximate composition, amino acids, nutritional values of the protein, and dietary fiber fractions of SBT_LVs of four cultivars (cvs.) Ascola, Habego, Hergo, and Leikora were assessed. SBT_LVs from different years of the study had statistically different levels of crude protein, ether extract, crude ash, and nitrogen-free extract (NFE), confirming that the quality of the raw material (leaves) can be significantly modified by habitat conditions. The largest fraction of dietary fiber was neutral detergent fiber (NDF), including the sum of hemicellulose, cellulose, and lignin, followed by the acid detergent fiber fraction (ADF), consisting of lignin and cellulose. The content of essential amino acids in SBT_LV protein was high. Overall, this study confirms that SBT_LVs hold promise as a valuable resource for use as a food ingredient, functional food, and dietary supplement for both humans and animals.

Impact of Malting and Moist-steaming on Carbohydrate and Dietary Fibre Quotient of Millets and its Utilization in the Preparation of Low Estimated Glycemic Index and High Fibre Pizza Base

Background: The Carbohydrate and dietary fibre quotients (CQ and DFQ) are an indication of total carbohydrate, dietary fibre and its fractions viz. soluble and insoluble. Malting is a nutrition transition natural method having many benefits. Further, a resistant starch (RS) is called a fraction of dietary fibre which forms on heating starch rich foods. Millets were malted and moist steamed in order to improve CQ and DFQ and used in preparation of pizza base. Methods: The moist steamed millets (MSM) malt was analyzed under Scanned Electronic Microscopic (SEM) to detect RS. The developed pizza base was analyzed for proximate composition, in-vitro digestibility and Estimated Glycemic Index (EGI) etc. Result: The SEM of moist steamed malt showed the retrograded starch molecules as an effect of moist steaming and cooling process. The proximate composition of pizza base showed a significant change in all parameter on fortification. The microbial parameters were slightly affected on fortification. The total starch, rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) content were too reduced on fortification. The Hydrolysis Index (HI) and Estimated Glycemic Index (EGI) were too decreased from 45.06 to 31.74 and 64.45 to 53.14 respectively on fortification. Hence, it is concluded that the MSM malt utilization in pizza base has impact on overall quality of pizza base including physico-chemical properties, microbial and EGI. The high fibre and RS millets malt could be utilized in the preparation of high fibre and low EGI pizza base.

Impact of dietary fiber fraction of chia seed supplementation on hepatic steatosis and other metabolic disturbances in a high-fat diet model

Metabolic dysfunction-associated steatotic liver disease (MASLD), characterized by hepatic triglyceride elevation is prevalent globally and often leads to significant consequences such as steatosis and hepatocarcinoma. In association with insulin resistance, oxidative stress, and inflammation, effective interventions are essential. Dietary fiber plays a crucial role in regulating these metabolic parameters. Chia (Salvia hispanica L.), a fiber-rich oilseed, is known for its high fiber content. This study assessed the impact of the fiber-rich fraction of partially defatted chia seeds (FFC) on hepatic steatosis and metabolic disturbances induced by a high-fat diet (HFD) in mice. Male C57BL/6J mice were fed either a control diet (CD) or HFD for 10 weeks, followed by FFC or oatmeal supplementation for an additional 4 weeks. FFC intake significantly reduced hepatic steatosis, lowered triglyceride and cholesterol levels, normalized plasma triglycerides, decreased oxidative stress, and attenuated inflammation. FFC has emerged as a promising candidate for managing hepatic steatosis.

Effects of wheat bran dietary fiber fractions on markers of intestinal health

Effects of wheat bran dietary fiber fractions on markers of intestinal health

Colonic fermentation of enzymatically treated cocoa bean shells (CBSs) and short chain fatty acids (SCFAs) production.

Cocoa bean shells (CBSs) are a by-product of the cocoa production chain characterized by a substantial dietary fiber (DF) content. The aim of this work was the evaluation of the prebiotic activity of DF from raw CBSs as well as defatted and dephenolized CBSs (polyphenols in their free form) treated with different enzymes mixtures to increase the fermentable fiber portion. Fermentability was tested through an in vitro model of colon fermentation using microbiota selectively adapted to more proximal and most distal compartments of the colon. Results showed a significant amount of short chain fatty acids (SCFAs) produced, particularly acetate, from fermentation of the lipid- and polyphenols-free CBS treated with the cellulase mixture. In both colonic regions, this sample boosted the production of SCFAs, suggesting the potential usefulness of this enzyme-driven processing to improve the prebiotic effect of CBS. Despite these findings, there was not a change in the DF content of the enzymatically treated samples, especially regarding the soluble dietary fiber (SDF) fraction. This outcome suggests that a structural change may have occurred in the fiber fraction increasing its fermentability. These outcomes open a new scenario in the bio-valorization of CBSs, in accordance with the concept of circular economy.

Development of a protocol for fractionating and characterising fibres from lignocellulosic food waste

This study aims to explore an advanced protocol for characterising dietary fibre (DF) fractions to meet the growing demand for accurate and reliable data. Although current enzymatic-gravimetric approaches, e.g., AOAC and Van Soest analysis, provide information about soluble and insoluble DF quantification, they present limitations related to the lack of fractions characterisation. To overcome these limitations, the proposed protocol integrates the official AOAC 991.43 method with the sequential fibre fractionation by exploiting the different resistance of the fibre fractions to acid hydrolysis treatments (TFA and H2SO4), utilising hazelnut shells as a case-study. Each hydrolysed fraction was quantified and characterised through GC–MS analysis of monosaccharides. The data obtained for hemicellulose, cellulose, and lignin fractions were then discussed and compared with the Van Soest method. This approach yields a comprehensive procedure applicable to different food and nutraceutical products, emphasising the importance of DF characterisation for a deeper understanding of their bio-functional properties.

Influence of Dehulled African Breadfruit Substitution on Starch Digestibility, Dietary Fibre and Glycemic Index of High-Fibre Snack Bars from Maize and Coconut Flour Blends

In this article, African breadfruit seeds were dehulled and made into flour alongside maize and coconut, and the flours were analyzed for their particle sizes and nutritive value. Snack bars were prepared by substituting different levels of dehulled African breadfruit (Treculia africana) seed flour with maize flour at a constant level of coconut grits viz., 0:95:5=T0, 20:75:5=T1, 25:70:5=T2, 30:65:5=T3, 35:60:5=T4, 95:0:5=T5. The snack bars were analyzed for their starch fractions, in vitro starch digestibility, glycemic index and dietary fibre fractions. Rapidly digestible starches (RDS) ranged from 26.32 – 34.62 %, slowly digestible starches (SDS) ranged from 34.46 – 38.71 %, and resistant starch (RS) content was from 3.15 to 9.24 %, while total starch content (TS) was 62.44 – 72.42 %. In vitro starch digestibility (IVSD) and glycemic index (IVGI) ranged from 34.29 – 57.48 % and 47.32 – 57.34 % respectively. Dietary fibre content showed 3.46 – 5.18%, 6.66 – 13.72% and 10.72 – 17.18 % for soluble dietary fibre (SDF), insoluble dietary fibre (IDF) and total dietary fibre (TDF) respectively. SDS and SDF increased, while IVSD and IVGI decreased significantly (p<0.05) with increase in dehulled African breadfruit flour substitution. The higher the TDF, the lower the glycemic index (GI) of the snack bars. All snack bars prepared showed high fibre content and low – medium GI, indicating that they could be useful for consumers interested in weight management or battling diabetes.

Techno-functional characteristics, mineral composition and antioxidant potential of dietary fiber extracted by sonication from different oat cultivars (Avena sativa)

Metabolic disorders including hypertension, diabetes and cardiovascular disease etc. are the major threats to public health and economy. Management and prevention of alarmingly increased aforementioned disorders has attracted researchers to explore their natural remedies. The objective of this study was to explore ultrasonically extracted dietary fibers from indigenous oat cultivars (SGD2011, Avon, SGD81, PD2LV65, and S2000) for their techno-functional characteristics, mineral composition and phytochemicals. These characteristics will find the way to ultimately use oats in food and feed industries to address consumer demand. Extraction of dietary fibers from oat cultivars was optimized by response surface methodology. These cultivars varied significantly (p < 0.05) for oil holding capacity, water saturation and water holding capacity. The SGD81 cultivar showed the highest oil holding capacity, water holding capacity and water saturation due to its highest fraction of dietary fiber. The highest values of total phenolic contents, total flavonoid contents, total flavonol contents, 2,2-Diphenyl-1-picrylhydrazyl radical scavenging activity, and anthocyanins were shown by SGD81, and SGD2011. All cultivars varied significantly (p < 0.05) with respect to phytochemical quantification. The cultivars SGD81 and SGD2011 showed the best phenolic acid profile and can be effectively used as source of nutraceutical. Beyond well-established nutritional properties of oat, these may also contribute dietary fibers for their nutraceutical properties. This approach can protect people from metabolic disorders. Moreover, extraction of dietary fibers through sonication can be considered an eco-friendly strategy.

Fabrication of textured functional ingredient based on apple: Sesame by-product

The search for new sources of fortified components from low-cost and sustainable sources has become a trend in the last decade. Food byproducts containing valuable bioactive compounds such as dietary fiber, protein, and phytochemicals are being used as substrates for obtaining beneficial components that can promote health. Extrusion is an efficient technology for converting food by-products into nutrient-rich food ingredients. The objective of this work was to optimize the extrusion process to obtain the best combination of moisture content (14, 18 and 22%) and screw speed (SS) (120,150 and180 rpm), apple pomace (AP): semi-defatted sesame cake (SDSC) blends (25:75, 50:50 and 75:25 w/w) to fabricate textured functional ingredients (TFI) with high values of expansion ratio (ER), water absorption index (WAI), brightness level, total phenolic compounds (TPC) and antioxidant activity (AA) and lower hardness based on a central composite design. The optimal treatment was determined at 176 rpm SS, 18% moisture content and a ratio of (75:25) AP: SDSC. The desirability value has indicated an appropriate match between the predicted and the observed response. TFI exhibited higher soluble dietary fiber fraction (WAI) values and lower plate count values during 30 days of storage compared to the unprocessed by-product, suggesting that TFI could be successfully used for the manufacture of innovative, high quality products such as porridge, beverages, cookies, soups and others that could provide health benefits based on the values obtained.

Comprehensive Evaluation of the Nutritional Properties of Different Germplasms of Polygonatum cyrtonema Hua.

Polygonatum cyrtonema Hua, an edible resource and medical material, is mainly consumed as a food in China. However, few published studies have comprehensively assessed its nutritional components. In this study, the proximate, carbohydrate, and dietary fiber contents as well as the mineral, vitamin, and amino acid compositions of five sources of P. cyrtomena grown in Yuhang district, Hangzhou city, Zhejiang province, were investigated. The nutritional profile of the five germplasms was investigated using analytical chemistry methods. All germplasms had a low starch content and contained greater amounts of carbohydrates (23.25-34.29%), protein (2.96-5.40%), Ca (195.08-282.08 mg/100 g), Fe (29.68-59.37 mg/100 g), and vitamin C (60.49-149.86 mg/100 g) in comparison to ginger, yam, and potatoes. The polysaccharide content ranged from 16.92% to 28.48%, representing the main source of carbohydrates. Fructose, a desirable sweetener, was the most abundant monosaccharide, representing 1.06% to 4.88% of the content. P. cyrtonema was found to be high in dietary fiber, with pectin and resistant starch being the major soluble components and hemicellulose being the dominant insoluble dietary fiber. A correlation analysis (CA) revealed significant correlations for the carbohydrate components and dietary fiber fractions with other nutrients. A principal component analysis (PCA) identified significant differences between the nutritional characteristics of the five germplasms, with Huanggang having the highest comprehensive quality scores. Moreover, ten nutrient components were selected as potential indicators that could be used to further evaluate the nutritional quality of P. cyrtomena. Our results demonstrate the rich nutrient composition and characteristics of P. cyrtonema and provide a valuable reference for the future development and utilization of Polygonatum.

Influence of Dietary Fibre and Protein Fractions on the Trace Element Bioaccessibility of Turnip Tops (Brassica rapa) Growing under Mediterranean Conditions

The objective of this work was to study the influence of three dietary fibre fractions (pectin, gum arabic and cellulose) and three protein fractions (casein, lactalbumin and soy) on the trace element bioaccessibility (Fe, Mn, Ni, Se and Zn) of turnip tops (B. rapa subsp. Rapa) growing under Mediterranean conditions. Then, it aimed to promote the use of this vegetable not only for direct fresh consumption but also as a main ingredient in the development of food mixtures. The results showed that soluble fibre fractions, such as pectin and gum arabic, can enhance the bioaccessibility of trace elements, such as Fe, Mn, Se and Zn. This effect was not proved for cellulose (an insoluble fibre fraction), in which, at best, no bioaccessibility effect was observed. Regarding the protein fractions, with the exception of Se, caseins and lactalbumin had a neutral effect on improving the trace element bioaccessibility. This did not hold true for soy protein, in which a considerable improvement in the bioaccessibility of Fe, Mn, Se and Zn was determined.

Identification and structural characterization of key prebiotic fraction of soluble dietary fiber from grapefruit peel sponge layer and its regulation effect on gut microbiota

In this study, the key prebiotic fraction of grapefruit peel sponge layer soluble dietary fiber (GSLSDF) was identified, and its structure characteristics and modulatory effect on intestinal microorganisms were investigated. Firstly, two fractions (GSLSDF-1 and GSLSDF-2) were isolated from GSLSDF, and the GSLSDF-1 showed a better prebiotic activity. Subsequently, GSLSDF-1 was found to have a low molecular weight and crystallinity, a loose and porous microstructure, and a high glucose content. Meanwhile, GSLSDF-1 was a dextran with a main chain linked by β-1, 4 glycosidic bonds and branched by a β-1, 6 glycosidic bonds. These structural characteristics were responsible for the favorable prebiotic activity of GSLSDF-1. Finally, the regulation effect of GSLSDF-1 on gut microbiota was analyzed in vitro fecal fermentation. Compared with the blank and GSLSDF groups, GSLSDF-1 could increase the relative abundances of Lactobacillus, Bacteroides, Bifidobacterium and Faecalibacterium coupled with decrease the relative abundances of Clostridium and Clostridioides. Furthermore, GSLSDF-1 promoted the production of short-chain fatty acids (SCFAs) by modulating the SCFAs synthesis pathway of intestinal microorganisms, while the NH3-N synthesis of intestinal microorganisms was inhibited by GSLSDF-1. Above results indicated that GSLSDF-1 was the key prebiotic fraction of GSLSDF, which could effectively optimize the intestinal microorganism composition.

Fractionation and physicochemical characterization of dietary fiber of kenaf (Hibiscus cannabinus L.) seed.

Kenaf seeds are underutilized kenaf plant by-products, containing essential nutrients including dietary fiber (DF), which can be potentially utilized as food ingredients. The present study aimed to evaluate the physicochemical characteristics of kenaf seed fiber fractions extracted from kenaf seed. Defatted kenaf seed powder yielded four DF fractions: alkali-soluble hemicellulose (146.4 g kg-1 ), calcium-bound pectin (10.3 g kg-1 ) and acid-soluble pectin (25.4 g kg-1 ) made up the soluble fibre fraction, whereas cellulose (202.2 g kg-1 ) comprised the insoluble fraction. All fractions were evaluated for their physicochemical properties. The DF fractions contained glucose, mannose, xylose and arabinose, and a small amount of uronic acid (1.2-2.7 g kg-1 ). The isolated pectin fractions had a low degree of esterification (14-30%). All the isolated DF fractions had high average molecular weights ranging from 0.3 to 4.3 × 106 g mol-1 . X-ray diffractogram analysis revealed that the fractions consisted mainly of an amorphous structure with a relative crystallinity ranging from 31.6% to 44.1%. The Fourier-transform infrared spectroscopy spectrum of kenaf seed and its DF fractions showed typical absorption of polysaccharides, with the presence of hydroxyl, carboxyl, acetyl and methyl groups. Scanning electron microscopy analysis demonstrated that the raw material with the rigid structure resulted in soluble and insoluble DF fractions with more fragile and fibrous appearances, respectively. The soluble DF demonstrated greater flowability and compressibility than the insoluble fractions. These findings provide novel information on the DF fractions of kenaf seeds, which could be used as a potential new DF for the food industry. © 2023 Society of Chemical Industry.

Biovalorization of mango byproduct through enzymatic extraction of dietary fiber.

Mango is considered one of the most important tropical fruits worldwide in terms of its consumption and consumer acceptability. Its processing generates huge quantities of mango byproducts, which is often discarded unscrupulously into the environment and, therefore, needs effective waste management practices. The extraction of mango peels' dietary fiber using enzymatic method can be a useful valorization strategy for management of mango by-products. In the present investigation, dietary fiber (soluble and insoluble fraction) was extracted by enzymatic hydrolysis using α-amylase, protease, and amyloglucosidase. Highest yield of dietary fiber (67.5%, w/w) was obtained at 60°C temperature using recommended enzyme concentrations including α-amylase (40 µL), protease (110 µL), and amyloglucosidase (200 µL) after a treatment time of 60min. SEM analysis indicated the increased porosity of dietary fiber samples caused due to the hydrolytic effect of enzymes on its surface structure, whereas FTIR analysis confirmed the functional groups present in dietary fiber. The coexistence of crystalline and amorphous nature of polymers present in soluble and insoluble fractions of dietary fiber was assessed by XRD analysis. Further, the analysis of functional properties including WHC, OHC, and SC revealed the suitability of using extracted mango peel's dietary fiber in the food systems.

Effects of ultra-fine micronization on the structure, rheological and functional properties of dietary fiber from Laminaria japonica

Laminaria japonica is known to be a rich source of dietary fiber (DF). The DF in L. japonica was extracted by combined enzymatic and chemical method in this study. The effect of ultra-fine pulverization on structural and functional properties of DF fractions were also investigated. The results displayed that the molecular weight of DF was 2.22 × 107 Da. After ultra-fine grinding, the viscosity of soluble dietary fiber (SDF) suspension increased from 4.65 ± 0.08 to 6.89 ± 0.24 mPa·s. In addition, ultra-fine grinding significantly reduced the particle size of DF with higher insoluble dietary fiber (IDF) yields. L. japonica IDF exhibited significant enhancement on absorption capacities of nitrite ion absorption, cholesterol and glucose, which could be utilized as potential ingredients in several DF intensified foods. This work could provide understanding into the influence of micronization on the structure-function relationship of food materials rich in dietary fiber.

Dietary fibre fractions rich in (poly)phenols from orange by-products and their metabolisation by in vitro digestion and colonic fermentation

Orange peel is an interesting by-product because of its composition, particularly its dietary fibre and flavanones. The aim of this work was to extract different fibre fractions from orange peel to obtain potential added-value ingredients and evaluate how the presence of fibre may interfere with (poly)phenol metabolism. Using an aqueous extraction, as a green extraction method, an insoluble fibre fraction (IFF) and a water-soluble extract (WSE) were obtained. Those fractions were analysed to determine the proximate and dietary fibre composition, hydration properties, (poly)phenol composition and antioxidant capacity, comparing the results with the orange peel (OP). The IFF presented the highest content of insoluble dietary fibre and the WSE showed the highest content of (poly)phenols, these being mainly flavanones. An in vitro faecal fermentation was carried out to evaluate the production of short-chain fatty acids (SCFAs) and lactate as prebiotic indicators; the IFF gave the highest production, derived from the greater presence of dietary fibre. Moreover, catabolites from (poly)phenol metabolism were also analysed, phenylpropanoic acids being the major ones, followed by phenylacetic acids and benzoic acids. These catabolites were found in higher quantities in WSE, because of the greater presence of (poly)phenols in its composition. IFF also showed a significant production of these catabolites, which was delayed by the greater presence of fibre. These results reveal that the new ingredients, obtained by an environmentally friendly water extraction procedure, could be used for the development of new foods with enhanced nutritional and healthy properties.

Low-molar-mass oat beta-glucan impacts autophagy and apoptosis in early stages of induced colorectal carcinogenesis in rats

Oat beta-glucan is one of the soluble dietary fibre fractions with a wide spectrum of biological activities such as anti-inflammatory and anti-tumour properties. In the present study, the effect of low-molar-mass oat beta-glucan isolate (OβGl) on the level of autophagy and apoptosis in the colorectum of rats with induced early stages of colorectal cancer was investigated. Forty-five male Sprague-Dawley rats were divided into two main groups: control and azoxymethane-induced early-stage colorectal carcinogenesis (CRC). Both groups were divided into three dietary subgroups fed standard feed without OβGl (OβGl−), with 1 % of OβGl (OβGl+1 %) or with 3 % of OβGl (OβGl+3 %). The expression of autophagy (LC3B, beclin-1) and apoptosis (caspase-3, cleaved caspase-3, BAX, BCL-2 and PARP-1) markers was determined by immunohistochemistry, Western blot and PCR analysis. The obtained results showed that the expression of LC3B, caspase-3 and cleaved caspase-3 in the CRC mucosa, and LC3B-II expression in the CRC wall were higher in the OβGl+3 % compared to the OβGl− rats. A higher BAX/BCL-2 ratio was also observed in the CRC OβGl+1 % rats compared to the other CRC animals. In summary, OβGl+3 % has a modulatory effect, stimulating autophagy and the extrinsic apoptosis pathway, while OβGl+1 % has a stimulatory effect on the intrinsic apoptosis pathway.