Search Results (11)

In this study, feruloylated arabinoxylans (FAXs) extracted from nixtamalized maize bran were assessed as a functional ingredient in white bread. FAXs were added at percentages of 0.15% and 0.30% to bread, and a control sample without FAXs was prepared. Regarding texture profile analysis, hardness values in bread treated with FAXs ranged from 34.32 N (T5) to 51.03 N (T3), with all values for FAXs-added bread being lower than 64.43 N obtained for the control sample (TC). With respect to color, most of the FAX-treated samples had higher overall values than the control sample, with L* values ranging from 50.49 (T4) to 59.40 (T6). The total color difference (ΔE) values ranged from 2.07 (T2) to 6.32 (T6), indicating differences between the control sample and the FAX-treated samples. In the analysis of proximate composition, all FAX-treated bread had higher levels of crude fiber content than the control sample, and water activity (aw) values were lower in the control sample than in bread treated with FAXs. Regarding total phenols, FAX-treated bread ranged from 1.57 (T6) to 1.98 (T1) mgFAE/g, being higher than the 1.24 mgFAE/g found in the control sample (TC). The antioxidant capacity levels, namely, DPPH, ABTS, and FRAP, were 9.36–17.01, 8.86–17.64, and 3.05–5.07 µmolTE/g, respectively. Thus, it is possible to conclude that adding FAXs to bread formulations improves the hardness, crude fiber content, and functional properties of bread. Full article

Cereals are among the foods rich in myo-inositol hexakisphosphate (phytic acid, IP6), lower myo-inositol phosphates (IPx), a wide range of phenolic compounds, as well as vitamins, minerals, oligosaccharides, phytosterols and para-aminobenzoic acid, and are attributed with multiple bioactivities, particularly associated with the prevention of metabolic syndrome and colon cancer. The bran fraction of wheat, maize, brown rice and other cereals contains high levels of phytate, free and total phenolics, and endogenous enzymes such as amylases, phytase, xylanase, β-glucanase and feruloyl esterase, whose activities can be increased by germination. The preliminary steps of digestion begin in the oral cavity where substrates for the action of endogenous cereal and salivary enzymes start to be released from the food matrix. IP6 released from phytate complexes with arabinoxylans, starch and protein bodies would eventually enhance the absorption of nutrients, including phenolics, by regulating tight junctions and, together with ferulic acid (FA), would maintain cell barrier integrity and epithelial antibacterial immunity. In addition, both IP6 and FA exert potent and complementary antioxidant effects, while FA together with IPx generated through advanced hydrolysis of IP6 by endogenous and microbial phytases may affect digestive enzyme activity and incretin secretion, resulting in modulated insulin and glucagon release and prevention of various diabetic complications. Contrary to widespread negative attitudes towards phytate, in this review, we present the strategy of selecting cereals with high phytate and phenolic content, as well as high endogenous phytase, feruloyl esterase and endoxylanase activities, to produce value-added health-promoting foods. The advanced hydrolysis of phytate and phenolic compounds by cereal and/or microbial enzymes would generate substantial amounts of “enzymatically generated inositol” (EGI), including IP6, IPx and myo-inositol, the compounds that, together with free FA, provide enhanced bioavailability of cereal nutrients through multiple synergistic effects not previously realised. Full article

Feruloylated arabinoxylan (AX) is a potential health-promoting fiber ingredient that can enhance nutritional properties of bread but is also known to affect dough rheology. To determine the role of feruloylation and hydrolysis of wheat bran AX on dough quality and microstructure, hydrolyzed and unhydrolyzed AX fractions with low and high ferulic acid content were produced, and their chemical composition and properties were evaluated. These fractions were then incorporated into wheat dough, and farinograph measurements, large and small deformation measurements and dough microstructure were assessed. AX was found to greatly affect both fraction properties and dough quality, and this effect was modulated by hydrolysis of AX. These results demonstrated how especially unhydrolyzed fiber fractions produced stiff doughs with poor extensibility due to weak gluten network, while hydrolyzed fractions maintained a dough quality closer to control. This suggests that hydrolysis can further improve the baking properties of feruloylated wheat bran AX. However, no clear effects from AX feruloylation on dough properties or microstructure could be detected. Based on this study, feruloylation does not appear to affect dough rheology or microstructure, and feruloylated wheat bran arabinoxylan can be used as a bakery ingredient to potentially enhance the nutritional quality of bread. Full article

Rice bran, rich in feruloyl arabinoxylan, is a good source of feruloyl oligosaccharides (FOs). To prepare FOs, bran was often hydrolyzed by amylase and protease to remove starch and protein and then hydrolyzed by xylanase, which was time-consuming and had a low yield. To solve the above problems, enzymatic extrusion was used to treat rice bran, and the effects of traditional hydrolysis, a combination of traditional extrusion and hydrolysis (extrusion-hydrolysis) and enzymatic extrusion on the yield of FOs were investigated and compared in this study. It was found that traditional extrusion and enzymatic extrusion significantly increased the yield of FOs. Particularly, the yield of FOs resulting from enzymatic extrusion was increased to 5.78%, while the yield from traditional hydrolysis was 4.23%. Microscopy analysis showed that extrusion damaged the cell wall of bran, which might increase the accessibility of xylanase to arabinoxylan and the yield of FOs. Spectroscopy analysis suggested that FOs obtained by different pretreatments had similar structures. It was obvious that enzymatic extrusion saved the time for removal of starch and protein and increased the yield of FOs. In addition, the highest yield of FOs was found at the moisture content of 30% and the screw speed of 50 rpm. This study provided an efficient method for the preparation of FOs that is suitable for industrial production. Full article

This article summarizes evolving concepts and scientific findings on cell wall feruloylation and ferulate oxidative coupling processes in grasses, and the effects these have on the wide range of cell wall properties and consequent plant responses to biotic and abiotic stress and tissue degradability. Updates of the different strategies that have been applied to genetically modifying cell wall feruloylation are presented. Special emphasis is given to the modification of cell wall feruloylation by heterologous expression of cell wall ferulic acid esterase, as this strategy has provided insights into the impact of feruloylation on the changes in the physicochemical properties of the cell wall with consequent effects on different plant processes. Emerging feruloyl transferase candidate genes codifying enzymes accounting for ferulate incorporation into grass arabinoxylans are also highlighted. Full article

A series of polymers, including chitosan (CS), carboxymethylcellulose (CMC) and a chitosan–gelatin (CS–GEL) hybrid polymer, were functionalized with ferulic acid (FA) derived from the enzymatic treatment of arabinoxylan through the synergistic action of two enzymes, namely, xylanase and feruloyl esterase. Subsequently, the ferulic acid served as the substrate for laccase from Agaricus bisporus (AbL) in order to enzymatically functionalize the above-mentioned polymers. The successful grafting of the oxidized ferulic acid products onto the different polymers was confirmed through ultraviolet–visible (UV–Vis) spectroscopy, attenuated total reflectance (ATR) spectroscopy, scanning electron microscopy (SEM) and nuclear magnetic resonance (NMR) spectroscopy. Additionally, an enhancement of the antioxidant properties of the functionalized polymers was observed according to the DDPH and ABTS protocols. Finally, the modified polymers exhibited strong antimicrobial activity against bacterial populations of Escherichia coli BL21DE3 strain, suggesting their potential application in pharmaceutical, cosmeceutical and food industries. Full article

This study aimed to investigate the effect of arabinoxylans (AX) partial de-esterification with feruloyl esterase on the polysaccharide conformational behavior, topographical features, and antioxidant activity. After enzyme treatment, the ferulic acid (FA) content in AX was reduced from 7.30 to 5.48 µg FA/mg polysaccharide, and the molecule registered a small reduction in radius of gyration (RG), hydrodynamic radius (Rh), characteristic ratio (C∞), and persistence length (q). A slight decrease in α and a small increase in K constants in the Mark–Houwink–Sakurada equation for partially de-esterified AX (FAX) suggested a reduction in molecule structural rigidity and a more expanded coil conformation, respectively, in relation to AX. Fourier transform infrared spectroscopy spectra of AX and FAX presented a pattern characteristic for this polysaccharide. Atomic force microscopy topographic analysis of FAX showed a more regular surface without larger hollows in relation to AX. The antioxidant activity of FAX, compared to AX, was reduced by 30 and 41% using both 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS⁺) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) methods, respectively. These results suggest that feruloyl esterase treatment of AX could offer a strategy to tailor AX chains conformation, morphological features, and antioxidant activity, impacting the development of advanced biomaterials for biomedical and pharmaceutical applications. Full article

Agricultural residues are considered the most promising option as a renewable feedstock for biofuel and high valued-added chemical production due to their availability and low cost. The efficient enzymatic hydrolysis of agricultural residues into value-added products such as sugars and hydroxycinnamic acids is a challenge because of the recalcitrant properties of the native biomass. Development of synergistic enzyme cocktails is required to overcome biomass residue recalcitrance, and achieve high yields of potential value-added products. In this study, the synergistic action of two termite metagenome-derived feruloyl esterases (FAE5 and FAE6), and an endo-xylanase (Xyn11) from Thermomyces lanuginosus, was optimized using 0.5% (w/v) insoluble wheat arabinoxylan (a model substrate) and then applied to 1% (w/v) corn cobs for the efficient production of xylo-oligosaccharides (XOS) and hydroxycinnamic acids. The enzyme combination of 66% Xyn11 and 33% FAE5 or FAE6 (protein loading) produced the highest amounts of XOS, ferulic acid, and p-coumaric acid from untreated, hydrothermal, and acid pre-treated corn cobs. The combination of 66% Xyn11 and 33% FAE6 displayed an improvement in reducing sugars of approximately 1.9-fold and 3.4-fold for hydrothermal and acid pre-treated corn cobs (compared to Xyn11 alone), respectively. The hydrolysis product profiles revealed that xylobiose was the dominant XOS produced from untreated and pre-treated corn cobs. These results demonstrated that the efficient production of hydroxycinnamic acids and XOS from agricultural residues for industrial applications can be achieved through the synergistic action of FAE5 or FAE6 and Xyn11. Full article

Distiller’s dried grains with solubles (DDGS) are co-products of the maize ethanol industry. DDGS contains feruloylated arabinoxylans (AXs), which can present gelling, antioxidant, and health-promoting effects. However, AXs presenting high ferulic acid (FA) content can exhibit delayed fermentation by the colonic microbiota. Therefore, partial deferuloylation of AXs from DDGS while preserving the polysaccharide gelling and antioxidant properties could add value and favor the sustainable development of bioethanol plants. The aim of this work was to partially deferuloylated AXs from DDGS using feruloyl esterase and to evaluate the polysaccharide macromolecular characteristics, gelling, and antioxidant properties. The AXs presented FA and FA dimer contents of 3.27 and 0.30 µg/mg polysaccharide, respectively, which decreased to 1.26 and 0.20 µg/mg polysaccharide, respectively, in feruloyl esterase-treated AXs (FAXs). The molecular weight and intrinsic viscosity of FAXs were slightly less than those of AXs. The Fourier transform infrared spectroscopy data of AXs and FAXs were similar, confirming that the enzyme did not modify the polysaccharide molecular identity. FAX gels (2% w/v) exhibited a decrease in elasticity by 43% in relation to that of AXs gels. The antioxidant capacity of FAXs was reduced by 32% and 43% (DPPH and ABTS method, respectively), compared with that of AXs. The FAX gelling and antioxidant properties were -comparable to those reported for other AXs in the literature. Feruloyl esterase may offer an interesting approach for the design of functional FAXs as value-added products recovered from DDGS. Full article

Feruloylated arabinoxylans obtained from nixtamalized maize bran were evaluated in terms of physicochemical characteristics and antioxidant capacity when incorporated in frankfurter sausages. Concentrations of 0.15% and 0.30% of feruloylated arabinoxylans were incorporated in frankfurter sausages formulations and a control without feruloylated arabinoxylans was also prepared. Shear force, hardness, color measurement, proximate analysis, pH, titratable acidity, water-holding capacity, total phenols, and antioxidant capacity were evaluated. Phenolic content and antioxidant capacity were significantly higher (P < 0.0001) in all treatments, sausages containing feruloylated arabinoxylans compared to the control. The results showed that there was a significant difference (P < 0.0001) in total phenolic content and antioxidant capacity with all feruloylated arabinoxylans sausages treatments higher than control. Additionally, significant differences (P < 0.0001) were obtained in the physicochemical parameters. Full article

Whole grain rice is a rich source of fiber, nutrients, and phytochemicals that may promote gastrointestinal health, but such beneficial components are typically removed with the bran during polishing. Soluble feruloylated arabinoxylan oligosaccharides (FAXO) and polyphenols (RBPP) isolated from rice bran are hypothesized to have positive impacts on human gut microbiota through a prebiotic function. Using an in vitro human fecal fermentation bioassay, FAXO and RBPP treatments were assessed for short-chain fatty acids (SCFA) production patterns and by evaluating their impacts on the phylogentic composition of human gut microbiota by 16S rRNA gene sequencing. Fresh fecal samples collected from healthy adults (n = 10, 5 males, 5 females) were diluted with anaerobic medium. Each sample received five treatments: CTRL (no substrates), FOS (fructooligosaccharides), FAXO, RBPP, and MIX (FAXO with RBPP). Samples were incubated at 37 °C and an aliquot was withdrawn at 0, 4, 8, 12, and 24 h Results showed that SCFA production was significantly increased with FAXO and was comparable to fermentation with FOS, a well-established prebiotic. RBPP did not increase SCFA productions, and no significant differences in total SCFA production were observed between FAXO and MIX, indicating that RBPP does not modify FAXO fermentation. Changes in microbiota population were found in FAXO treatment, especially in Bacteroides, Prevotella, and Dorea populations, indicating that FAXO might modulate microbiota profiles. RBPP and MIX increased Faecalibacterium, specifically F. prausnitzii. Combined FAXO and RBPP fermentation increased abundance of butyrogenic bacteria, Coprococcus and Roseburia, suggesting some interactive activity. Results from this study support the potential for FAXO and RBPP from rice bran to promote colon health through a prebiotic function. Full article