Purification and characterisation of antioxidant and nitric oxide inhibitory peptides from Tilapia (Oreochromis niloticus) protein hydrolysate

Nitric oxide (NO)‐inhibitory and antioxidative activities of tilapia hydrolysates were prepared using ultrasound pretreatment at 70 W for 30 and 45 min, respectively, followed by Flavourzyme hydrolysis for 1 h. Both hydrolysates were fractionated using size exclusion chromatography on Sephadex G‐25 column and purified by RP‐HPLC. The amino acid sequence of the most potent and purified fractions was determined using LC/MS/MS. The antioxidant peptide (KAFAVIDQDKSGFIEEDELKLFLQNFSAGARAGDSDGDGKIGVDEFAALVK, MW: 6334.49 KDa) and NO‐inhibitory peptide (AFAVIDQDKSGFIEEDELKLFLQNFSAGARAGDSDGDGKIGVDEFAALVK, MW: 6309.49 Da) produced no cytotoxicity in RAW264.7 macrophage cell lines at the concentration of 100 mg mL^?1. The purified peptides at the concentration 100 μg mL^?1 possessed antioxidative and NO‐inhibitory activities 83.0 ± 1.1% and 40.9 ± 0.2%, respectively, which were about 100 times those of their counterpart crude hydrolysates.     

Optimization of Arabinoxylan Isolation from Rye Bran by Adapting Extraction Solvent and Use of Enzymes

Physicochemical and functional properties of arabinoxylans (AXs) can be significantly influenced by their isolation method. Finding balanced process conditions that allow optimal extraction yields while preserving AXs functionality is a challenge. The aim of this study was to determine the effect of different chemical solvents with neutral and alkaline pH on the intrinsic properties and extraction yield of AXs isolated from rye bran. Additionally, the application of xylanases and other cell wall degrading enzymes (Pentopan Mono BG, Deltazym XL‐VR, Viscoflow BG) to solubilize bound AXs was investigated. Results show that the use of Ca(OH)₂ for isolation was superior to water and Na₂CO₃, as it selectively solubilized AXs and delivered isolates with a purity of up to 43.92% AX and a moderate ferulic acid (FA) content (209.35 ± 16.79 mg FA/100 g AX). Application of xylanases was further able to duplicate these achieved AX yields (7.50 to 9.85g AX/100 g bran). Additionally, isolates displayed highest ferulic acid contents (445.18 to 616.71 mg FA/100 g AX) and lowest impurities in comparison to chemical extracted AXs. Rheological characterization of the isolates showed a pronounced shear thinning behavior which fitted well to the power‐law model (R² > 0.989). Differences in pseudoplasticity of the isolates suggested that structural and chemical properties might have been responsible for this behavior.     

Effects of pineapple pomace fibre on physicochemical properties of composite flour and dough,and consumer acceptance of fibre‐enriched wheat bread

Pineapple pomace fibre (PF, containing 70.2% total dietary fibre) can be added to increase dietary fibre of wheat bread. This study was performed to evaluate effects of PF added at 0, 5 or 10% (wheat flour‐basis) on physicochemical properties of the composite flour (wheat flour as the control, CPF‐5 and CPF‐10, respectively) and its dough, to evaluate consumer acceptance of CPF breads and to identify factors affecting willingness to purchase of CPF breads. Incorporating PF affected rheological and pasting properties of CPF. Water‐ and oil‐holding capacity of CPF increased (P < 0.05) as PF levels increased. Bread made with CPF‐5 was more acceptable than that with CPF‐10; however, it was not significantly different from the control, having similar specific volume and texture, but having about three times higher total dietary fibre than the control (4.4% vs. 1.5%). Product label and health benefit information potentially affected consumers' willingness to purchase of fibre‐enriched bread.     

The Effects of Whole Grain High‐Amylose Maize Flour as a Source of Resistant Starch on Blood Glucose,Satiety, and Food Intake in Young Men

The objective of this study was to determine the dose response effect of whole grain high‐amylose maize (HAM) flour as a source of resistant starch (RS) on blood glucose, appetite and short‐term food intake. In a repeated‐measures crossover trial, healthy men (n = 30, 22.9 ± 0.6 y, BMI of 22.6 ± 0.3 kg/m²) were randomly assigned to consume 1 of 3 cookies once a week for 3 wk. Cookies were control (100% wheat flour), low‐dose (63% wheat flour,37% HAM flour), and high‐dose (33% wheat flour, 67% HAM flour) providing 53.5, 43.5, and 36.3 g of available carbohydrate, respectively. Ad libitum food intake was measured 120 min at a pizza meal, blood glucose and subjective appetite were measured after consumption of the cookie (0 to 120 min) and after the pizza meal (140 to 200 min). Blood glucose concentrations were lower at 30 and 45 min after high‐dose treatment, and at 120 min after both high‐ and low‐dose treatments compared to control (P < 0.05). Blood glucose AUC before the pizza meal (0 to 120 min) was 44% and 14% lower, and higher by 43% and 41% after the pizza meal (140 to 200 min) compared with control. Yet despite the higher response following the meal, cumulative AUC (0 to 200 min) was still 22% lower after the high‐dose treatment (P < 0.05). All treatments equally suppressed subjective appetite and there was no effect on food intake. In conclusion, HAM flour as a source of RS and incorporated into a cookie was associated with better glycemic control in young men.     

Dietary Plant Sterols Supplementation Increases In Vivo Nitrite and Nitrate Production in Healthy Adults: A Randomized,Controlled Study

A randomized, double‐blinded, placebo‐controlled and crossover study was conducted to simultaneously measure the effects, 3 h after consumption and after 4‐wk daily exposure to plant sterols‐enriched food product, on in vivo nitrite and nitrate production in healthy adults. Eighteen healthy participants (67% female, 35.3 [mean] ± 9.5 [SD] years, mean body mass index 22.8 kg/m²) received 2 soy milk (20 g) treatments daily: placebo and one containing 2.0 g free plant sterols equivalent of their palmityl esters (β‐sitosterol, 55%; campesterol, 29%; and stigmasterol, 23%). Nitrite and nitrate concentrations were measured in the blood plasma and urine, using stable isotope‐labeled gas chromatography‐mass spectrometry. L‐arginine and asymmetric dimethylarginine concentrations in blood serum were measured using commercially available enzyme immunoassays. Nitrite and nitrate concentrations in blood plasma (nitrite 5.83 ± 0.50 vs. 4.52 ± 0.27; nitrate 15.78 ± 0.96 vs. 13.43 ± 0.81 μmol/L) and urine (nitrite 1.12 ± 0.22 vs. 0.92 ± 0.36, nitrate 12.23 ± 1.15 vs. 9.71 ± 2.04 μmol/L) were significantly elevated after 4‐wk plant sterols supplementation Placebo and 3‐h treatments did not affect the blood plasma and urinary concentrations of nitrite and nitrate. Circulating levels of L‐arginine and asymmetric dimethylarginine were unchanged in the placebo and treatment arms. Total plant sterols, β‐Sitosterol, campesterol, and stigmasterol concentrations were significantly elevated after 4‐wk treatments compared to the placebo and 3‐h treatments. Blood plasma nitrite and nitrate concentrations correlated significantly with the plasma total and specific plant sterol concentrations. Our results suggest that dietary plant sterols, in the combination used, can upregulate nitrite, and nitrate production in vivo.     

Effect of virgin coconut oil cake on physical,textural, microbial and sensory attributes of muffins

A study was carried out to develop muffins by substituting refined wheat flour (RWF) with virgin coconut oil (VCO) cake (0–50 g/100 g flour blend). Progressive replacement of RWF with VCO cake resulted in significant (P < 0.05) decrease in peak viscosity of flour blends (from 2527.75 cP in the control to 389.5 cP in 50 g VCO cake/100 g flour blend) and the muffins height (from 34.26 mm in the control to 26.88 mm in 50 g VCO cake/100 g flour blend). Significant colour change was observed in the crust and crumb regions. Free fatty acid and microbial analysis revealed that the quality of muffin samples was unaffected by the addition of VCO cake during 16‐day storage at both refrigerated (4 ± 2 °C) and ambient temperature (35 ± 2 °C). Incorporation of 40 g VCO cake/100 g flour blend significantly (P < 0.05) increased the overall acceptability of the muffins (with a maximum score of 8.5). Muffins with 40 g VCO cake/100 g flour blend were enriched with protein (8.49 g/100 g), fat (18.46 g/100 g), crude fibre (1.14 g/100 g) and minerals (1.15 g/100 g).     

Pretreatment eliminates throat irritation by water yam and facilitates the development of functional cookies

Water yam (Dioscoreaalata) provides sufficient nutrients in terms of protein (10.075 ± 0.02%), fibre (3.40 ± 0.03%) and minerals (potassium and phosphorous). However, due to the presence of anti-nutritional factors such as saponins, water yam causes throat irritation. Consequently, it is less preferred among consumers, and thus, the commercial importance of yam tubers has been limited. The current investigation aims to reduce the saponin content of water yam by pretreatment of yam tubers at the optimised conditions (blanching with 0.2% potassium metabisulphite, 0.5% tartaric acid and 0.5% citric acid) that rendered a 50% reduction in the saponin content (1.65% to 0.86%). The said nutritious yam flour was utilised as a replacement of refined wheat flour (13%) in the development of functional cookies. The yam cookies showed higher mineral content (phosphorous: 116.20 ± 0.80 mg/100 g; potassium: 221.11 ± 0.98 mg/100 g). Reduced water activity and incorporation of antioxidants in yam cookies decreased the peroxide value of the same during storage attesting its higher shelf-life.     

Antioxidant Extraction from Mustard (Brassica juncea) Seed Meal Using High‐Intensity Ultrasound

Brassicaceae oilseeds provide feedstocks for the biofuels industry, but value‐added coproducts are necessary to supply financial incentives for increased production. Our objective was to use high‐intensity ultrasound to optimize extraction of antioxidants from mustard (Brassica juncea) seed meal. The ultrasound‐assisted extraction (UAE) variables included temperature, solvent‐to‐material ratio, sonication duration, and EtOH concentration. Extracts were analyzed for total phenolics content (TPC), antioxidant activity, and sinapine content. Conventional extraction using water and 70% EtOH (v/v) at 80 °C for 3×30 min yielded 7.83 ± 0.07 and 8.81 ± 0.17 mg sinapic acid equivalents (SAE)/g meal, respectively. UAE extraction at 40 °C for 30 min yielded similar phenolics content (8.85 ± 0.33 mg SAE/g meal) as conventional hot ethanolic extraction, but required less time and lower temperature. The highest TPC (13.79 ± 0.38 mg SAE/g meal) was in the 7‐d aqueous extracts. Sonicated solutions of pure sinapine and sinapic acid showed 1st‐order reaction kinetics with greater degradation of isolated compounds than those present in extracts. Sinapine contained in extracts showed insignificant (P < 0.05) degradation after 30 min of sonication. Our research indicates that ultrasound treatment can assist the extraction of antioxidants from B. juncea meal by reducing both the temperature and time requirement without significant degradation of the primary antioxidants present.     

Anti-inflammatory effects of Punica granatum Linne in vitro and in vivo

Inflammation can cause various physical dysfunctions. Punica granatum Linne (pomegranate), a high phenolic content fruit, is widely used as an antipyretic analgesic in Chinese culture. Pomegranate has shown potential nitric oxide (NO) inhibition in LPS-induced RAW 264.7 macrophage cells. Moreover, pomegranate (100 mg/kg) significantly decreased carrageenan-induced mice paw edema for 1, 3, 4, and 5 h. Therefore, column chromatography combined with in vitro bioassay-guided fractionation was used to isolate the active anti-inflammatory components from the pomegranate. Punicalagin (1), punicalin (2), strictinin A (3), and granatin B (4) were obtained with yields of 0.093%, 0.015%, 0.003%, and 0.013%, respectively. All these hydrolysable tannins inhibited NO production and iNOS expression in RAW 264.7 cells. Among them, 4 showed the strongest iNOS and COX-2 inhibitory effects, and exhibited these effects in the inhibition of paw swelling and the PGE₂ level in carrageenan-induced mice. Taken together, we suggest that 4 could be used as a standard marker for the anti-inflammatory effect of pomegranate.     

Olive stone powder: A potential source of fiber and antioxidant and its effect on the rheological characteristics of biscuit dough and quality

Being waste products of olive fruits, olive stones could be used as a healthy functional food ingredient thanks to their rich antioxidant properties, nutrients and dietary fibers. In this study, wheat flour was substituted by olive stone powder at levels of 0, 5, 10 and 15%. The rheological properties of biscuit dough and proximate composition, color values, total phenolic content, antioxidant activity, textural characteristics and sensorial properties of biscuit samples were investigated. Wheat flour replacement by olive stone powder increased antioxidant activity, fat and fiber content of biscuit samples (p < 0.05). The biscuits prepared with addition of 15% olive stone powder had 30.44 ± 0.03% DPPH radical scavenging activity, 11.22 ± 0.09% crude fiber, and 26.32 ± 0.22% fat. According to results of sensory analysis, wheat flour could be substituted up to 15% by olive stone powder to prepare biscuits without causing unacceptable product in terms of sensory properties.     

Effect of dextrans of differing molecular weights on the rheology of wheat flour doughs and the quality characteristics of pan and arabic breads

Dextrans (α-1-6-D-glucans) with weight-average molecular weights (Mw) ranging from 10 to 500 kDa were used at a rate of 20 g kg^?1 (flour basis) in order to modify doughs made from flour of the Australian hard-grained wheat cultivars Banks, Sunco and Hartog. Doughs containing dextran fractions with Mw below 100 kDa showed significant (P ± 0.01) reductions in Farinograph maximal consistency and significant increases in Farinograph development time. Additions of dextrans also resulted in significant increases in maximal resistance and significant reductions in extensibility when doughs were subjected to Extensograph testing. After addition of dextran fractions with Mw of 100 kDa or less, there were significant reductions in loaf volumes in pan bread of the cultivar Hartog manufactured by a rapid dough system and in pan bread of the cultivars Banks and Hartog made by a fermented dough system. Arabic bread supplemented with dextrans had poorer internal and keeping qualities, and reduced bread surface area, leading to significantly decreased quality scores. These observations are discussed in relation to possible interactions between neutral polysaccharides and other flour components.     

Bovine casein peptides co‐stimulate naive macrophages with lipopolysaccharide for proinflammatory cytokine production and nitric oxide release

Three bovine casein peptides, ie LLY, PGPIPN and TTMPLW, were used to investigate their effects on cytokine (TNF‐α and IL‐6) production and nitric oxide (NO) release by murine bone marrow macrophages (BMMs). The results showed that these peptides alone were incapable of stimulating cytokine production or NO release in naive or IFN‐γ‐primed BMMs. However, when BMMs were co‐incubated with the peptides at a concentration of 1.0 µM and lipopolysaccharide (LPS; 100 ng ml⁻¹), an augmentative effect on TNF‐α, IL‐6 and NO production was observed. Of the three peptides, TTMPLW had the greatest augmentative effect on NO production by LPS‐stimulated BMMs and induced the highest amount of TNF‐α production at a concentration of 1.0 µM . All the peptides at a concentration of 1.0 µM stimulated IL‐6 production by BMMs. TNF‐α was neutralised by anti‐TNF‐α monoclonal antibody and the release of NO was reduced by about 33.3% (p < 0.01). These results demonstrate that bovine casein peptides can co‐stimulate naive macrophages with LPS for proinflammatory cytokine production and NO release and may play a role in host defence against pathogens. © 2000 Society of Chemical Industry     

Optimisation of pressurised liquid extraction for antioxidative polyphenolic compound from Momordica charantia using response surface methodology

Pressurised liquid extraction (PLE) of antioxidant compounds from bitter gourd fruits (Momordica charantia) in aqueous ethanolic solvent was investigated using response surface methodology at laboratory scale to understand key impact of extraction variables. Extraction efficiency was optimised by measuring the yield of extraction, total phenolic content (TPC), total flavonoid content (TFC), ferric reducing/antioxidant power assay (FRAP) and radical scavenging activity (RSA). The optimal extraction conditions were reached at 80% ethanol concentration, 10‐min extraction time and at 160 °C. Under these extraction conditions, values of TPC (5.40 ± 0.30 g GAE per 100 g), TFC (1.50 ± 0.10 g QE per 100 g), FRAP (778.55 ± 10 μmol eq Fe (II) g^?1), yield (178.50 ± 5.50 mg g^?1 dc) and RSA (75.50 ± 4.50%) were achieved. Furthermore, statistical analysis revealed that antioxidative attributes of bitter gourd extract were strongly and positively correlated with extraction temperature and ethanol concentration rather than processing time. This study illustrated that PLE has the potential to extract antioxidant compounds from tropical fruit vegetables in an accelerated manner. Furthermore, influential parameters affecting the process could be optimised for further industrial intake.     

Influence of different diets on some biological parameters of the Mediterranean flour moth,Ephestia kuehniella Zeller (Lepidoptera: Pyralidae)

The Mediterranean flour moth, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), is one of the most important pests of stored products, especially damaging cereals. Besides pest status, its eggs and larvae are commonly used for mass rearing of many natural enemies. Different diets are suggested for the production of E. kueniella, but the influence of diet supplements, such as yeast and glycerine on the performance of E. kuehniella diets are not clearly understood. In the present study, we investigated the effects of several diet ingredients on some major biological parameters of E. kuehniella. Ten diets based on different combinations of wheat flour, cornmeal, wheat bran, glycerine and yeast were tested in the experiments. Twenty eggs of E. kuehniella were added into 5 g of each diet within separate plastic cylindrical containers (5 cm height × 3 cm diameter) and incubated in climate rooms at 25 ± 1 °C and 60 ± 10 Relative Humidity (R.H) on a 14 h light: 10 h dark photoperiod. Pupal weight, developmental period, emergence ratio, fecundity and fertility were determined. The diet containing wheat flour, wheat bran, glycerine and yeast in a percentage of 53.33, 26.67, 15 and 5%, respectively, resulted in shorter development time and higher fertility, and could be used as an alternative to the standard diets currently used in insectaries.     

Nutritional Evaluation of Cereal–Cheese Whey Mixtures

The chemical composition, amino acid content, PER, and digestibility of dehydrated sweet cheese whey, wheat flour, wheat bran, and lime-treated corn flour (nixtamal, used for making tortillas), as well as of 21 cereal-cheese whey mixtures were determined. The cheese whey was composed of 12% protein and 74% lactose. Diets containing a total of 8% protein were formulated with the cereal-cheese whey mixtures. The 50:50 (% protein) cereal-whey mixtures had the highest adjusted modified PERs, representing an increase over the cereals alone of 324% for the corn flour, 215% for wheat flour, and 177% for wheat flour, and 177% for wheat bran. The 50:50 (% protein) wheat bran mixture had the largest adjusted modified PER at 2.33 ± 0.13 (mean ± SEM) and the 50:50 wheat flour mixture, the smallest at 1.48 ± 0.21. Although the apparent digestibility was reduced from 10–14% for the latter two 50:50 cereal-whey mixtures compared to the cereals alone, this was not reflected in the PER. It was concluded that the nutritive value of all the cereals tested significantly increased with the addition of 155 25% or more (by weight) of dehydrated cheese whey.     

The Phenolic Compounds,Metabolites, and Antioxidant Activity of Propolis Extracted by Ultrasound‐Assisted Method

The influences of ultrasound‐assisted, pharmacopeia, and supercritical fluid extraction methods on bioactive compounds and biological activities of propolis were evaluated. Results showed that propolis extracted by ultrasound‐assisted method contained more phenolic compounds, and showed the highest total phenolic content (245.84 ± 6.41 mg GAE/g DW), total flavonoids content (198.82 ± 5.74 mg RE/g DW), and stronger in vitro antioxidant activity (DPPH·: 1.03 ± 0.04 mmol Trolox/g DW, ABTS+·: 2.19 ± 0.05 mmol Trolox/g DW, and FRAP: 1.48 ± 0.12 mmol FeSO₄/g DW) than those of pharmacopoeia and supercritical fluid methods. A total of 36 phenolic compounds were identified in propolis. Among them, quercetin, quercetin‐3‐methyl‐ether, kaempferol, isorhamnetin, luteolin‐methyl‐ether, and quercetin‐7‐methyl‐ether could only be found in ultrasound‐assisted and pharmacopoeia methods. Moreover, the phenolic compounds had the similar metabolic pathways in rats and were mainly metabolized by sulfation and glucuronidation pathways. Additionally, ultrasonic‐treated propolis have good in vivo antioxidant activity and could repair D‐galactose‐induced oxidative damage in rats. Therefore, ultrasound‐assisted method could replace pharmacopeia method to be considered as bioactive compounds extraction from propolis, taking into consideration of yield, short extraction time, and high antioxidant activity.     

A study of the effect of the drying process on the composition and physicochemical properties of flours obtained from durian fruits of two ripening stages

Durian cv. Monthong with two ripening stages (unripe and fully ripe) was subjected to microwave vacuum drying (MWD) at 5.49 W g^?1 and hot air drying (HAD) at 60 °C. With an increase in ripening degree, the starch content was significantly (P ≤ 0.05) decreased from 40.08–40.42% to 9.44–11.76%. X‐ray diffraction indicated that the crystalline pattern was changed from starch to sucrose. The starch granule morphology of durian flour was conserved for both drying conditions. Peak gelatinisation temperatures of MWD and HAD flours were increased significantly (P ≤ 0.05) from 56.71–57.32 to 60.71–61.23 °C. Using different drying methods, MWD flour had less a*‐value (P ≤ 0.05) than HAD flour. The peak viscosity and trough of the HAD unripe durian flour (5.92 RVU and 3.45 RVU, respectively) were significantly (P ≤ 0.05) lower than those of the MWD unripe durian flour (34.32 RVU and 11.57 RVU, respectively).     

Influence of pressurised liquid extraction and solid–liquid extraction methods on the phenolic content and antioxidant activities of Irish macroalgae

The efficiencies of pressurised liquid extraction (PLE) and a traditional solid–liquid extraction (SLE) at extracting antioxidant polyphenols from Irish macroalgae Ascophyllum nodosum, Pelvetia canaliculata, Fucus spiralis and Ulva intestinalis were compared. PLE was more effective for extracting polyphenols with acetone/water (80:20); however, when food‐friendly solvents of ethanol/water (80:20) and water were employed, SLE resulted in higher phenolic content in brown macroalgal extracts. For example, the Fucus spiralis SLE water and ethanol/water extracts displayed total phenolic contents (TPCs) of 130.58 ± 2.78 and 142.81 ± 1.77 μg phloroglucinol equivalents (PGE) mg^?1 sample, respectively, compared with TPCs of 90.79 ± 1.16 and 124 ± 6.54 μg PGE mg^?1 sample for the corresponding PLE extracts. All SLE aqueous ethanolic macroalgal extracts possessed higher DPPH radical scavenging abilities (RSA) and ferric reducing antioxidant power (FRAP) than their PLE equivalents . This study indicates that the application of high extraction temperatures (50–200 °C) and pressures (500–3000 psi) used in PLE does not enhance the antioxidant activities of macroalgal extracts relative to SLE extraction. The ability to produce antioxidant food‐friendly macroalgal extracts using SLE could represent significant cost reductions on an industrial scale further enhancing the potential of macroalgal polyphenols to be used in functional food preparations.     

Solvent retention capacity values in relation to the Czech commercial wheat quality

Technological quality in the sets of eighty commercial wheat samples was evaluated by grain milling traits (test weight, thousand kernel weight, grain hardness as Particle Size Index, one‐stream flour yield) and common analytical parameters (wet gluten and protein contents, Zeleny test value, falling number) together with the solvent retention capacity (SRC) method (AACC 56‐11). For the commercial wheat, the latter analytical procedure (originally designed for flour quality analysis) was verified also for grain wholemeal. Within the mentioned sample group, anova revealed the strongest effect of the harvest year, both for milling and for technological parameters. For the SRC profiles, the effect of the sample form used dominated the crop year influence. The grain SRCs were correlated with the milling traits foursome, while an agreement between the flour SRC profiles and technological quality data was not so tight. However, the flour lactic acid SRC was associated with the wet gluten and protein contents (r = 0.24, P < 0.05), and the protein quality as Zeleny value with the flour water SRC (r = 0.24, P < 0.05). Relationship between Zeleny's value and flour lactic acid SCR was confirmed by nonlinear Spearman correlation (R = ?0.26, P < 0.05).     

Partial characterization of β‐ d‐xylosidase from wheat malts

Arabinoxylans (AXs) from wheat malts potentially affect beer quality and production. β‐ d ‐Xylosidase is a key enzyme that degrades the main chains of AXs to produce xylose. This study performed a partial characterization of β‐ d ‐xylosidase from wheat malts. The optimal temperature was 70 °C and the enzyme exhibited excellent thermostability, that is, residual activities were 92.6% at 60 °C for 1 h. The enzyme was stable over a pH range of 3.0–6.0 and showed optimum activity at pH 3.5 and 4.5. Kinetic parameters K_m and V_max of wheat malt β‐ d ‐xylosidase against p‐nitrophenyl‐xyloside were 1.74 mmol L⁻¹ and 0.76 m m min⁻¹, respectively. The enzyme activity was severely inhibited by Cu²⁺, moderately inhibited by Mn²⁺, Mg²⁺, Al³⁺, Ca²⁺, Ba²⁺ and Na⁺ and mildly inhibited by Fe³⁺ and Fe²⁺. The partial enzymatic characterization achieved in this study can be used as a theoretical basis for purifying β‐ d ‐xylosidase from wheat malts. Copyright © 2015 The Institute of Brewing & Distilling