Wheat Bran Extract Research Articles

Enhancement of Penicillium echinulatum glycoside hydrolase enzyme complex

The enhancement of enzyme complex produced by Penicillium echinulatum grown in several culture media components (bagasse sugarcane pretreated by various methods, soybean meal, wheat bran, sucrose, and yeast extract) was studied to increment FPase, xylanase, pectinase, and β-glucosidase enzyme activities. The present results indicated that culture media composed with 10 g/L of the various bagasse pretreatment methods did not have any substantial influence with respect to the FPase, xylanase, and β-glucosidase attained maximum values of, respectively, 2.68 FPU/mL, 2.04, and 115.4 IU/mL. On the other hand, proposed culture media to enhance β-glucosidase production composed of 10 g/L steam-exploded bagasse supplemented with soybean flour 5.0 g/L, yeast extract 1.0 g/L, and sucrose 10.0 g/L attained, respectively, 3.19 FPU/mL and 3.06 IU/mL while xylanase was maintained at the same level. The proteomes obtained from the optimized culture media for enhanced FPase, xylanase, pectinase, and β-glucosidase production were analyzed using mass spectrometry and a panel of GH enzyme activities against 16 different substrates. Culture medium designed to enhance β-glucosidase activity achieved higher enzymatic activities values (13 measured activities), compared to the culture media for FPase/pectinase (9 measured activities) and xylanase (7 measured activities), when tested against the 16 substrates. Mass spectrometry analyses of secretome showed a consistent result and the greatest number of spectral counts of Cazy family enzymes was found in designed β-glucosidase culture medium, followed by FPase/pectinase and xylanase. Most of the Cazy identified protein was cellobiohydrolase (GH6 and GH7), endoglucanase (GH5), and endo-1,4-β-xylanase (GH10). Enzymatic hydrolysis of hydrothermally pretreated sugarcane bagasse performed with β-glucosidase enhanced cocktail achieved 51.4 % glucose yield with 10 % w/v insoluble solids at enzyme load of 15 FPU/g material. Collectively the results demonstrated that it was possible to rationally modulate the GH activity of the enzymatic complex secreted by P. echinulatum using adjustment of the culture medium composition. The proposed strategy may contribute to increase enzymatic hydrolysis of lignocellulosic materials.

Process optimization for hyper production of xylanase via statistical methodology from isolated Bacillus pumilus 3GAH using lignocellulosic waste

Abstract Xylanases hold immense importance in many of the industrial applications for which their economic production at large scale is desired. Isolated xylanolytic strain Bacillus pumilus 3GAH with potential of high titre productivity was selected for subsequent optimization using wheat bran as a substrate. For this, Plackett Burman design was constructed with 11 process variables including media components (wheat bran, peptone, xylose, KNO3 and yeast extract), incubation conditions (shaking conditions, incubation temperature and incubation time), pH, inoculum age and inoculum size. As soon as the most significant factors were identified, they were used to construct Central Composite Design (CCD) within the range of xylose (0.01–0.32 g/50 ml), incubation time (12–26 h), yeast extract (0.01–0.32 g/50 ml), peptone (0.01–0.32 g/50 ml) and temperature (19.7–55.3 °C). CCD predicted the maximum xylanase activity (IU/ml) at the optimum conditions of xylose (0.1 g/50 ml), incubation time (22 h), yeast extract (0.1 g/50 ml), peptone (0.1 g/50 ml) and temperature (30 °C) while the fixed variables were wheat bran (0.3 g/50 ml), KNO3 (0.1 g/50 ml), inoculum size (0.5 ml), inoculum age (16 h) and shaking at 120 rpm. These statistical designs altogether resulted in approximately 1430 IU/ml xylanase activity translating to around 200,200 IU/gds (per gram dry substrate) with 24 fold increase as compared to unoptimised 8310 IU/gds; hence proving its utility.

Rye and Wheat Bran Extracts Isolated with Pressurized Solvents Increase Oxidative Stability and Antioxidant Potential of Beef Meat Hamburgers.

Rye and wheat bran extracts containing phenolic compounds and demonstrating high DPPH• (2,2-diphenyl-1-picrylhydrazyl), ABTS(•+) (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) scavenging and oxygen radical absorbance capacities (ORAC) were tested in beef hamburgers as possible functional ingredients. Bran extracts significantly increased the indicators of antioxidant potential of meat products and their global antioxidant response (GAR) during physiological in vitro digestion. The extracts also inhibited the formation of oxidation products, hexanal and malondialdehyde, of hamburgers during their storage; however, they did not have significant effect on the growth of microorganisms. Hamburgers with 0.8% wheat bran extract demonstrated the highest antioxidant potential. Some effects of bran extracts on other quality characteristics such as pH, color, formation of metmyoglobin were also observed, however, these effects did not have negative influence on the overall sensory evaluation score of hamburgers. Consequently, the use of bran extracts in meat products may be considered as promising means of increasing oxidative product stability and enriching with functional ingredients which might possess health benefits.

Effects of wheat bran extract rich in arabinoxylan oligosaccharides and resistant starch on overnight glucose tolerance and markers of gut fermentation in healthy young adults.

Specific combinations of dietary fiber (DF) have been observed to result in improved glucose tolerance at a subsequent standardized breakfast. Arabinoxylan oligosaccharides (AXOS) are considered as DF with prebiotic potential, but so far no studies have investigated their metabolic effects in humans. This randomized cross-over study evaluated the overnight impact of breads containing AXOS-rich wheat bran extract and resistant starch (RS, Hi-Maize), separately or combined, on glucose tolerance, related metabolic parameters and markers of gut fermentation in healthy subjects. Evening reference and test products were: (1) reference white wheat flour bread (WWB), WWB supplemented with (2) AXOS and RS (WWB+AXOS+RS), (3) an increased content of either AXOS (WWB+hiAXOS) or (4) RS (WWB+hiRS). At the subsequent standardized breakfast, blood was sampled for 3h to monitor glucose, insulin, nonesterified fatty acids, glucagon-like peptide (GLP)-1 and GLP-2. Breath hydrogen (H2) and short chain fatty acids (SCFA) were measured as markers of gut fermentation, and subjective appetite was rated using visual analog scales. Dose-dependent decreases in glucose responses were observed with increased AXOS over the duration of 3h. Insulin sensitivity index was improved in the morning after the WWB+hiAXOS evening meal. An increase in breath H2 concentration and circulating SCFA was observed in the morning after both evening meals containing AXOS. The present study indicates that AXOS have the potential of improving glucose tolerance in an overnight perspective and suggested mechanisms are improved insulin sensitivity and increased gut fermentation.

Protective Effect of Wheat Bran Extract against β-Amyloid-induced Cell Death and Memory Impairment

Objectives : The aim of this study is to examine the neuroprotective effect of wheat bran extract (WBE) against β-amyloid (Aβ)-induced apoptotic cell death in SH-SY5Y human neuroblastoma cells and memory impairment in triple transgenic animal model's of Alzheimer's disease (3xTg AD mice). Methods : In SH-SY5Y cells, MTT assay and TUNEL staining were conducted to evaluate the protective effect of WBE against Aβ25-35-induced neurotoxicity and apoptosis. Alterations in mitochondrial transmembrane potential (MMP), expression of proapoptotic Bax and antiapoptotic Bcl-2 proteins, cleavage of PARP, and brain-derived neurotrophic factor (BDNF) levels were analyzed to elucidate the neuroprotective mechanism of WBE. To further investigate the memory enhancing effect of WBE, Morris water maze test was performed in 3xTg AD mice. Results : In SH-SY5Y cells, WBE protected against Aβ25-35–caused cytotoxicity and apoptosis as shown by the restoration of cell viability in MTT assay and inhibition of DNA fragmentation in TUNEL staining. Aβ25-35– induced apoptotic signals such as dissipation of MMP, decreased Bcl-2/Bax ratio, and cleavage of PARP were suppressed by WBE. Moreover, WBE up-regulated the protein levels of BDNF, which seemed to be mediated by activation of cAMP response element-binding protein (CREB). In 3xTg AD mice, oral administration of WBE attenuated learning and memory deficit as verified by reduced mean escape latency in water maze test. Conclusions : WBE protects neuronal cells from Aβ25-35–induced apoptotic cell death and restores learning and memory impairments in 3xTg AD mice. These findings suggest that WBE exhibit neuroprotective potential for the management of AD.

베타아밀로이드로 유도된 신경세포 사멸과 기억력 손상에 대한 밀기울추출물의 보호효과

Objectives : The aim of this study is to examine the neuroprotective effect of wheat bran extract (WBE) against <TEX>${\beta}$</TEX>-amyloid (<TEX>$A{\beta}$</TEX>)-induced apoptotic cell death in SH-SY5Y human neuroblastoma cells and memory impairment in triple transgenic animal model's of Alzheimer's disease (3xTg AD mice). Methods : In SH-SY5Y cells, MTT assay and TUNEL staining were conducted to evaluate the protective effect of WBE against <TEX>$A{\beta}_{25-35}$</TEX>-induced neurotoxicity and apoptosis. Alterations in mitochondrial transmembrane potential (MMP), expression of proapoptotic Bax and antiapoptotic Bcl-2 proteins, cleavage of PARP, and brain-derived neurotrophic factor (BDNF) levels were analyzed to elucidate the neuroprotective mechanism of WBE. To further investigate the memory enhancing effect of WBE, Morris water maze test was performed in 3xTg AD mice. Results : In SH-SY5Y cells, WBE protected against <TEX>$A{\</TEX><TEX>beta}_{25-35}$</TEX>-caused cytotoxicity and apoptosis as shown by the restoration of cell viability in MTT assay and inhibition of DNA fragmentation in TUNEL staining. <TEX>$A{\beta}_{25-35}$</TEX>-induced apoptotic signals such as dissipation of MMP, decreased Bcl-2/Bax ratio, and cleavage of PARP were suppressed by WBE. Moreover, WBE up-regulated the protein levels of BDNF, which seemed to be mediated by activation of cAMP response element-binding protein (CREB). In 3xTg AD mice, oral administration of WBE attenuated learning and memory deficit as verified by reduced mean escape latency in water maze test. Conclusions : WBE protects neuronal cells from <TEX>$A{\beta}_{25-35}$</TEX>-induced apoptotic cell death and restores learning and memory impairments in 3xTg AD mice. These findings suggest that WBE exhibit neuroprotective potential for the management of AD.

High dose of prebiotics reduces fecal water cytotoxicity in healthy subjects.

In vitro and animal studies have shown differential colonic fermentation of structurally different prebiotics. We evaluated the impact of two structurally different prebiotics (wheat bran extract (WBE, containing arabinoxylan-oligosaccharides) and oligofructose) on colonic fermentation and markers of bowel health in healthy volunteers. Nineteen healthy subjects completed a double-blind, cross-over randomized controlled trial. Interventions with WBE, oligofructose or placebo for 2 wk (week 1: 15 g/day; week 2: 30 g/day) were separated by 2-wk wash-out periods. At the end of each study period, colonic fermentation was characterized through a metabolomics approach. Fecal water genotoxicity and cytotoxicity were determined using the comet and WST-1 assay, respectively, as parameters of gut health. Cluster analysis revealed differences in effects of WBE and oligofructose on colonic fermentation. WBE, but not oligofructose, reduced fecal p-cresol (p = 0.009) and isovaleric acid concentrations (p = 0.022), markers of protein fermentation. Fecal water cytotoxicity was significantly lower after intake of WBE (p = 0.015). Both WBE- and oligofructose-intake tended to reduce fecal water genotoxicity compared to placebo (WBE: p = 0.060; oligofructose: p = 0.057). Changes in fermentation were not related to changes in fecal water toxicity. Structurally different prebiotics affect colonic fermentation and gut health in a different way.

Hot water extract of wheat bran attenuates white matter injury in a rat model of vascular dementia.

Vascular dementia is characterized by white matter lesions involving the demyelination and activation of astrocytes and microglia. In a previous study, we showed that the supernatant of a laboratory-scale, hot water extract of ground whole wheat (TALE) attenuated white matter injury and astrocytic activation in a rat model of bilateral common carotid artery occlusion (BCCAO). In the present study, we made several modifications to the hot water extraction process to remove starch and enable large-scale production. We used wheat bran (WB), which contains less starch, instead of ground whole wheat. In addition, we removed starch granules with a decanter before hot water extraction. The final product, wheat bran extract (WBE), contained 2.42% arabinose, a surrogate marker of arabinoxylan, which is an active constituent of WBE. Supplementation of the rat model of BCCAO with WBE (400 mg/kg/day) for 33 days attenuated white matter injury, which was assessed by Luxol Fast Blue staining, in the corpus callosum (cc) and optic tract (opt) regions. Attenuation of white matter injury in the opt region was accompanied by improvement of the pupillary light reflex. Immunochemical staining revealed that supplementation with WBE reduced astrocytic activation in the cc and opt regions and reduced microglial activation in the opt region. These findings indicate that supplementation with WBE is effective at attenuating white matter injury accompanied by the inhibition of astrocytic and microglial activation. Therefore, extracts from WB, a cheap by-product of wheat milling, can be developed as a nutraceutical to prevent vascular dementia, a disease for which there is no approved pharmaceutical treatment.

A proteinaceous fraction of wheat bran may interfere in the attachment of enterotoxigenic E. coli K88 (F4+) to porcine epithelial cells.

Wheat bran (WB) from Triticum aestivum has many beneficial effects on human health. To the best of our knowledge, very little has been published about its ability to prevent pathogenic bacterial adhesion in the intestine. Here, a WB extract was fractionated using different strategies, and the obtained fractions were tested in different in vitro methodologies to evaluate their interference in the attachment of enterotoxigenic Escherichia coli (ETEC) K88 to intestinal porcine epithelial cells (IPEC-J2) with the aim of identifying the putative anti-adhesive molecules. It was found that a proteinaceous compound in the >300-kDa fraction mediates the recognition of ETEC K88 to IPEC-J2. Further fractionation of the >300-kDa sample by size-exclusion chromatography showed several proteins below 90 kDa, suggesting that the target protein belongs to a high-molecular-weight (MW) multi-component protein complex. The identification of some relevant excised bands was performed by mass spectrometry (MS) and mostly revealed the presence of various protease inhibitors (PIs) of low MW: Serpin-Z2B, Class II chitinase, endogenous alpha-amylase/subtilisin inhibitor and alpha-amylase/trypsin inhibitor CM3. Furthermore, an incubation of the WB extract with ETEC K88 allowed for the identification of a 7S storage protein globulin of wheat, Globulin 3 of 66 kDa, which may be one of the most firmly attached WB proteins to ETEC K88 cells. Further studies should be performed to gain an understanding of the molecular recognition of the blocking process that takes place. All gathered information can eventually pave the way for the development of novel anti-adhesion therapeutic agents to prevent bacterial pathogenesis.

Effects of Wheat Bran Extract Containing Arabinoxylan Oligosaccharides on Gastrointestinal Parameters in Healthy Preadolescent Children

We assessed whether wheat bran extract (WBE) containing arabinoxylan-oligosaccharides (AXOS) elicited a prebiotic effect and modulated gastrointestinal (GI) parameters in healthy preadolescent children upon consumption in a beverage. This double-blind randomized placebo-controlled crossover trial evaluated the effects of consuming WBE at 0 (control) or 5.0 g/day for 3 weeks in 29 healthy children (8-12 years). Fecal levels of microbiota, short-chain fatty acids, branched-chain fatty acids, ammonia, moisture, and fecal pH were assessed at the end of each treatment and at the end of a 1-week run-in (RI) period. In addition, the subjects completed questionnaires scoring distress severity of 3 surveyed GI symptoms. Finally, subjects recorded defecation frequency and stool consistency. Nominal fecal bifidobacteria levels tended to increase after 5 g/day WBE consumption (P = 0.069), whereas bifidobacteria expressed as percentage of total fecal microbiota was significantly higher upon 5 g/day WBE intake (P = 0.002). Additionally, 5 g/day WBE intake induced a significant decrease in fecal content of isobutyric acid and isovaleric acid (P < 0.01), markers of protein fermentation. WBE intake did not cause a change in distress severity of the 3 surveyed GI symptoms (flatulence, abdominal pain/cramps, and urge to vomit) (P > 0.1). WBE is well tolerated at doses up to 5 g/day in healthy preadolescent children. In addition, the intake of 5 g/day exerts beneficial effects on gut parameters, in particular an increase in fecal bifidobacteria levels relative to total fecal microbiota, and reduction of colonic protein fermentation.

New properties of wheat bran: anti‐biofilm activity and interference with bacteria quorum‐sensing systems

Some plant extracts, have been demonstrated to interfere with the microbial metabolism of several pathogenic bacteria. Within this antimicrobial properties it has been described the potential to inhibit or destroy biofilms or to interfere in quorum-sensing (QS) systems. However, to our knowledge, no study exploring this potential of wheat-bran (WB) has been published. The purpose of the present study is to evaluate the anti-biofilm activity of WB against a cow mastitis strain of Staphylococcus aureus and also its possible interference with bacterial QS systems. The potential of inhibition and destruction of the biofilm was studied by different in vitro assays. Also, we tested the ability of WB to interfere in bacterial QS by degrading acyl-homoserine lactones (AHL) as one of the most studied QS signal molecules for Gram-negative bacteria. The soluble extract of WB at 0.5% showed anti-biofilm activity, inhibiting biofilm formation and also destroying it. Similarly, the > 300 kDa fraction from WB had significant anti-biofilm activity in both in vitro assays. The WB also showed a potential to interfere with bacterial QS systems, as it was demonstrated to contain certain lactonase activity able to reduce AHL concentration in the medium. The present study reveals two additional beneficial properties of WB extract never explored before, which may be related to the presence of defence compounds in the plant extract able to interfere with microbial biofilms and also QS systems.

Tolerance and the effect of high doses of wheat bran extract, containing arabinoxylan-oligosaccharides, and oligofructose on faecal output: a double-blind, randomised, placebo-controlled, cross-over trial.

Wheat bran extract (WBE) is a food-grade soluble fibre preparation that is highly enriched in arabinoxylan-oligosaccharides. In this placebo-controlled cross-over human intervention trial, tolerance to WBE as well as the effects of WBE on faecal parameters, including faecal output and bowel habits, were studied. After a 2-week run-in period, twenty healthy volunteers consumed WBE (15g/d in the first week, 30g/d in the second week), oligofructose (15g/d in the first week, 30g/d in the second week) and placebo (for 2 weeks) in a random order, with 2-week washout periods between each treatment period. Subjects collected a 72h stool sample for analysis of faecal output, stool pH and stool moisture concentration. Additionally, the volunteers completed questionnaires scoring occurrence frequency and distress severity of eighteen gastrointestinal (GI) symptoms. An overall GI symptom measure was calculated to analyse the overall effect of WBE and oligofructose on GI symptoms. Intake of both 30g/d WBE and 30g/d oligofructose lowered stool pH, indicative of increased colonic fermentation, and increased stool moisture concentration as compared with placebo intake. Intake of 30g/d oligofructose increased the overall GI symptom measure by 1·9-fold as compared with placebo intake. Intake of WBE at doses up to 30g/d did not affect the overall GI symptom measure. WBE exerts beneficial effects on stool characteristics and is well tolerated at up to 30g/d. Oligofructose exerts comparable beneficial effects on stool characteristics. However, intake of 30g/d oligofructose appears to cause GI discomfort to some extent.

Production, characterization and applications of tannase

Tannases, tannin acylhydrolases, are an important group of biotechnologically relevant enzymes which were utilized in a number of industrial applications, including the manufacture of instant tea, beer, fruit juices, some wines and gallic acid production. Tannases are by and large produced by microorganisms including Aspergillus, Paecilomyces, Lactobacillus and Bacillus. Tannases are generally produced on tannic carbon such as tannic acid, wheat bran, tea and coffee husk extract. Microbial tannases are mostly induced extracellular enzyme and produced by submerged fermentation and solid-state fermentation. The enzyme is most commonly purified by hydrophobic interaction chromatography in addition to reverse micelle. Most tannases can act in a wide range of temperature and pH, although tannases with acidic pH optima are more common. A sequence-based classification spreads tannases in many families thus reflecting the variety of molecules. Furthermore, tannase from Lactobacillus plantarum had been characterized by three-dimensional architecture. In recent years, a novel approach, metagenomic, was developed to exploring novel tannase from natural communities.

Medium optimization using mathematical statistics for production of β-Carotene by Blakeslea trispora and fermenting process regulation

Optimization of medium components for enhancement of β-carotene production by Blakeslea trispora was achieved using mathematical statistics. Optimum concentrations of components using Plackett-Burman design and response surface methodology (RSM) were d-glucose 7.16%, wheat bran extract 4.08%, MgSO4 0.04%, soybean oil 3%, thiamine 0.01%, soybean meal 1%, and KH2PO4 0.2%. Maximum production of β-carotene using optimized medium was 643 mg/L in a shake flask. A predicted value of 669 mg/L was based on results of an RSM regression. The optimum aeration rate of 1.5 vvm produced 866 mg/L and the optimum agitation speed of 100 rpm produced 975 mg/L of β-carotene. The t of a quadratic model using regression derived coefficients was significant. Maximum production of β-carotene using the optimized medium in a stirred tank reactor (10 L) at an optimal aeration rate and an optimum agitation speed with addition of 0.1%(v/v) β-ionone was 1,357 mg/L.

Determination of Deoxynivalenol in Wheat Bran and Whole-Wheat Flour by Fluorescence Polarization Immunoassay

A rapid and accurate fluorescence polarization (FP) immunoassay has been optimized for the determination of deoxynivalenol (DON) in wheat bran and whole-wheat flour. A preliminary treatment with activated charcoal was used to eliminate the strong matrix effect due to highly colored interfering compounds present in raw wheat bran extracts. In particular, matrix effect was removed by adding activated charcoal to the wheat bran extract (3.5 mg/mL) and mixing for 3 min of incubation time prior to the FP immunoassay analysis. No preliminary treatment was necessary for whole-wheat flour. Average recoveries from samples spiked with DON at levels of 500, 1,000, and 1,500 μg/kg were 95 % for wheat bran and 94 % for whole-wheat flour, with relative standard deviation generally lower than 13 %. Limits of quantification of the optimized FP immunoassay were 120 μg/kg for both matrices. The overall time of analysis was lower than 15 min for wheat bran and 10 min for whole-wheat flour. Good correlations (r > 0.971) were observed between DON contents obtained by both FP immunoassay and high-performance liquid chromatography with immunoaffinity cleanup for 37 and 23 samples of naturally contaminated wheat bran and whole-wheat flour, respectively. These results show that the FP immunoassay is suitable for high-throughput screening as well as for quantitative determination of DON in wheat bran and whole-wheat flour.

Wheat Bran for Colon Cancer Prevention: Phytochemicals vs. Fiber

Many studies have found that dietary cereal fibers protect against colon cancer, however, not all cereal fibers are equally effective. Wheat bran is the only cereal bran that shows consistent protection against colon cancer in laboratory animal models, and corn and oat bran may enhance colon tumorigenesis. It is still unclear whether the active components are phytochemicals or fibers. We and others have found that phytochemicals in wheat bran instead of fiber are the major active components for colon cancer prevention. The inhibitory effect of wheat bran extract on tumorigenesis was observed in our studies in the Apcmin/+ mouse model. Using human colon cancer cells (HCT‐116 and HT‐29) as the guiding assay, we identified 5‐n‐alkylresorcinols (ARs) as the major components in wheat bran for colon cancer prevention. To further study the structure‐activity relationship of ARs, we synthesized more than 20 ARs derivatives. The effects of the length of the alkyl side chain, the substitution pattern of the functional groups on alkyl side chain, the substitution pattern on the benzene ring as well as the underlying molecular mechanism were also studied. The effects of other components in wheat bran, such as sphingolipids and steroids, will also be discussed.

Structure Elucidation and Chemical Profile of Sphingolipids in Wheat Bran and Their Cytotoxic Effects against Human Colon Cancer Cells

Sphingolipids are known to have diverse properties and physiological functions. These distinctive lipids have been identified in wheat bran, a food well-known for its chemopreventive activity. However, the complete profile of sphingolipids in wheat bran and their contributions to the cancer preventive effect of wheat bran have not been fully explored until this study. Twelve sphingolipids (1-12) were purified from wheat bran extract and characterized by analyzing their 1D and 2D NMR spectra, and seven sphingolipids (13-19) were characterized based on their tandem mass spectra (MS(n): n = 2-4). To the best of our knowledge, this is the first report of sphingolipids 1, 6-9, 11-14, and 16-19 in wheat bran. In particular, 2-N-(2'-hydroxy-15'-tricosenoyl)-4-hydroxysphinganine (peak 17) is a novel compound. Additionally, compounds 2-4 were reported with complete NMR data for the first time. Sphingolipids (1-12) showed little growth inhibition against human colon cancer cell lines (HCT-116 and HT-29) in vitro.

Production of tyrosinase by Auricularia auricula using low cost fermentation medium

Low cost fermentation media using agricultural by-products (wheat bran extract, rice bran extract and soybean meal extract) as a major nutrient source, were evaluated for the production of tyrosinase from the fungus Auricularia auricula in submerged culture. In single-factor experiments, three components (wheat bran extract, casein and CuSO4) were chosen to further optimize medium composition using response surface methodology (RSM). The central composite experimental results showed the following optimum medium composition: wheat bran extract 36.0 %, casein 1.1 g/l and CuSO4 0.13 g/l. Under these conditions, the highest tyrosinase activity was 17.22 U/ml, which was 2.1 fold higher than that obtained using the non-optimized medium. The present study is the first to report the statistical optimization of medium composition for production of tyrosinase by A. auricula using cheaper wheat bran extract as a major nutrient source. These results might provide a reference for the development of a cost-effective medium for commercial production of tyrosinase.

Digestive and physiologic effects of a wheat bran extract, arabino-xylan-oligosaccharide, in breakfast cereal

ObjectiveWe assessed whether a wheat bran extract containing arabino-xylan-oligosaccharide (AXOS) elicited a prebiotic effect and influenced other physiologic parameters when consumed in ready-to-eat cereal at two dose levels. MethodsThis double-blind, randomized, controlled, crossover trial evaluated the effects of consuming AXOS at 0 (control), 2.2, or 4.8 g/d as part of ready-to-eat cereal for 3 wk in 55 healthy men and women. Fecal microbial levels, postprandial serum ferulic acid concentrations, and other physiologic parameters were assessed at the beginning and end of each condition. ResultsThe median bifidobacteria content of stool samples (log10/grams of dry weight [DW]) was found to be higher in the subjects consuming the 4.8-g/d dose (10.03) than in those consuming 2.2 g/d (9.93) and control (9.84, P < 0.001). No significant changes in the populations of other fecal microbes were observed, indicating a selective increase in fecal bifidobacteria. Postprandial ferulic acid was measured at 120 min at the start and end of each 3-wk treatment period in subjects at least 50 y old (n = 37) and increased in a dose-dependent manner (end-of-treatment values 0.007, 0.050, and 0.069 μg/mL for the control, AXOS 2.2 g/d, and AXOS 4.8 g/d conditions, respectively, P for trend < 0.001). ConclusionThese results indicate that AXOS has prebiotic properties, selectively increasing fecal bifidobacteria, and increases postprandial ferulic acid concentrations in a dose-dependent manner in healthy men and women.

Effects of a wheat bran extract containing arabinoxylan oligosaccharides on gastrointestinal health parameters in healthy adult human volunteers: a double-blind, randomised, placebo-controlled, cross-over trial

Wheat bran extract (WBE) is a food-grade soluble fibre preparation that is highly enriched in arabinoxylan oligosaccharides. In this placebo-controlled cross-over human intervention trial, tolerance and effects on colonic protein and carbohydrate fermentation were studied. After a 1-week run-in period, sixty-three healthy adult volunteers consumed 3, 10 and 0g WBE/d for 3 weeks in a random order, with 2 weeks' washout between each treatment period. Fasting blood samples were collected at the end of the run-in period and at the end of each treatment period for analysis of haematological and clinical chemistry parameters. Additionally, subjects collected a stool sample for analysis of microbiota, SCFA and pH. A urine sample, collected over 48h, was used for analysis of p-cresol and phenol content. Finally, the subjects completed questionnaires scoring occurrence frequency and distress severity of eighteen gastrointestinal symptoms. Urinary p-cresol excretion was significantly decreased after WBE consumption at 10g/d. Faecal bifidobacteria levels were significantly increased after daily intake of 10g WBE. Additionally, WBE intake at 10g/d increased faecal SCFA concentrations and lowered faecal pH, indicating increased colonic fermentation of WBE into desired metabolites. At 10g/d, WBE caused a mild increase in flatulence occurrence frequency and distress severity and a tendency for a mild decrease in constipation occurrence frequency. In conclusion, WBE is well tolerated at doses up to 10g/d in healthy adults volunteers. Intake of 10g WBE/d exerts beneficial effects on gut health parameters.