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The water, ethanol, and methanol extracts of Vaccinium Bracteatum Thunb. leaves (VBTL) were investigated for their potential antioxidant activity. The total phenolic content was determined, and the antioxidant activity of the extracts was assessed by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging analysis. Five phenolic compounds including quercetin, kaempferol, luteolin, apigenin, and chrysin, were identified in the ethanol extract by high pressure liquid chromatography (HPLC).

The defatted rice endosperm protein (REP) was, respectively, digested by five different protease treatments (Alcalase, Chymotrypsin, Neutrase, Papain and Flavorase), and Neutrase appears to be the most desirable for producing high quality antioxidant peptides from REP. Specially, the DPPH and hydroxyl radical scavenging activities of NHREP were higher than its superoxide radical scavenging activity, and the percentage inhibition of autooxidation of NHREP (80.09%) was similar to that of α-tocopherol (86.59%) on day 5. Furthermore, NHREP was purified consecutively, and the antioxidant peptides were identified to be Phe-Arg-Asp-Glu-His-Lys-Lys (FRDEHKK, 959.5 Da) and Lys-His-Asp-Arg-Gly-Asp-Glu-Phe (1002.5 Da) by MALDI-TOF/TOF MS/MS. Lastly, FRDEHKK was chemically synthesised. It significantly inhibited lipid peroxidation in an linoleic acid emulsion system more effectively than α-tocopherol, and enhanced the viability of t-BHP induced cytotoxicity up to 74.38% (for MRC-5) and 78.39% (for RAW264.7) at 80 μg/ml. Conclusively, it was feasible to produce natural antioxidants from REP.

A novel method for the continuous production of γ-aminobutyric acid (GABA) using immobilized rice bran was developed. Calcium alginate gel was used to entrap rice bran directly and orthogonal array design was used to obtain the optimal conditions for immobilization. Under these conditions, the preservation of glutamate decarboxylase (GAD) activity was 48.94%. The optimum temperature for immobilized rice bran GAD activity was found to be 45°C with the optimum pH at 5.5. The thermostability, pH stability, operation and storage stability of GAD were improved by immobilization on rice bran. Based on these characteristics, a column reactor of immobilized rice bran was applied to produce GABA continuously. The GABA produced in 60 h by this method was 88.11% of the GABA produced by the free rice bran method, while the protein and sugar contents of the product were greatly reduced. The high output and purity of the product permit its biotechnological potential to be exploited in food applications.

The defatted rice endosperm protein (REP) was digested using five different proteases (Alcalase, Chymotrypsin, Neutrase, Papain, and Flavorase) to produce the antioxidative peptide. The degree of hydrolysis of REP by Neutrase (20.00%) was slightly lower than that of Chymotrypsin, but higher than those of other enzymes. The Neutrase hydrolysate from rice endosperm protein (NHREP) took on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity similar to α-tocopherol. Also, the reaction condition of Neutrase hydrolysis was moderate (pH of 7.0 and temperature of 37 °C). Therefore, Neutrase was chosen to be the optimum enzyme for producing the antioxidative peptide from REP. In succession, the antioxidant activities of NHREP were further evaluated. The median effective concentration (EC50) value of NHREP for hydroxyl radical scavenging activity was 2.0 mg/mL, while its superoxide radical scavenging activity did not surpassed 50% even at 6 mg/mL. The percentage inhibition of autooxidation in linoleic acid system by NHREP was 82.09%, similar to that of α-tocopherol (86.59%) on day 5 at the same concentration. NHREP displayed 89.15% chelating effect on ferrous ion at a concentration of 1000 μg/mL, and a high correlation was also observed between the reducing power and antioxidant activity of NHREP (r2 = 0.99678). Consequently, NHREP was purified and identified, and the sequence determination by MALDI-TOF/TOF MS/MS revealed that the active constituent contained eight amino acids in its sequence (Lys-His-Asn-Arg-Gly-Asp-Glu-Phe), with the molecular mass of 1002.5217 Da. After sequence interpretation and database searching, the MS/MS spectrum was matched to glutelin protein f (460–465).

The study investigated enzymatic pretreatment of oat bran, using Viscozyme L to enhance protein extraction. Response surface methodology (RSM) was used to study the effects of pretreatment variables of Viscozyme L concentration (6–30 FBG), pH (3.0–5.0), incubation time (0.5–2.5 h) and temperature (35–55 °C) on protein extraction from oat bran. The results indicated that the generated regression model represented the relationship between the independent variables and the responses. Protein extraction from oat bran was mainly affected by pH and incubation temperature. From the RSM-generated model, the optimum conditions of enzymatic pretreatment were identified as Viscozyme L concentration 30 FBG/10 g of oat bran, pH 4.6, incubation time 2.8 h and temperature 44 °C. Under the optimum conditions, the predicted protein extracted from oat bran was 55.7%, whereas, the experimental extracted protein was 56.2%. The RSM-predicted and experimental extracted proteins were not significantly different from each other. The enzymatic pretreatment method under the optimum conditions extracted significantly more protein (56.2%) than did the alkaline (pH 9.5) method (14.76%). Viscozyme L pretreatment of oat bran improved protein extraction.

A growth-promoting medium was developed to enhance the production of a hydroxyl radical inhibitory water-soluble protein from germinated millet. The single factor test indicated that H2O2 plays a key role in the inhibition activity. An optimal medium composition, consisted of H2O2, gibberellin, Protamex and Tween-40, was achieved using statistical experimental designs. A fractional factorial design was applied to determine the key factors that affected the hydroxyl radical scavenging activity, and a central composite experimental design and response surface methodology were used to optimize those factors, respectively. A second-order polynomial prediction equation was obtained, that could determine the effects of H2O2 and Protamex on the response. It was found that a low concentration of H2O2 and Protamex could enhance the inhibition of hydroxyl radicals. The optimal medium composition for growth-promoting was as follows: H2O2 1.56 mL/100 mL, gibberellin 0.2595 mg/L, Protamex 0.25 mg/mL and Tween-40 0.7 mL/100 mL. With the optimal medium, the highest hydroxyl radical inhibition (58.16%) was achieved.

A novel antitumor protein, coded as TBWSP31, was isolated from tartary buckwheat water-soluble extracts and purified by DEAE-Sepharose Fast Flow anion exchange, Sephadex G-100 gel filtration, and Sephacryl S-200 gel filtration column chromatography. TBWSP31 was identified to a homogeneous fraction by native PAGE. The antitumor effect of TBWSP31 against human mammary cancer cell Bcap37 was measured by an MTT assay. TBWSP31 showed higher antitumor activity, and time- and concentration-dependent effects were observed. SDS-PAGE analysis showed that TBWSP31 is composed of a single polypeptide with an approximate molecular weight of 57 kDa. TBWSP31 was rich in Glx (Gln+Glu), Arg, and Asx (Asp+Asn) according to amino acid analysis. Secondary structural analysis by CD spectroscopy revealed that TBWSP31 has the following: alpha-helix (33.9%), beta-sheet (22.8%), beta-turn (11.3%), and random coil (32.0%).

The antioxidant activities of different polarity solvents extracts from barley were evaluated by various antioxidant assays, including reducing power, free radical scavenging and lipid oxidation inhibition. Those various antioxidant activities were compared to standard antioxidants, butylated hydroxyluene (BHT) and ascorbic acid (Vit. C). The properties of the extracting solvents significantly affected the total phenolics, proanthocyanidins and antioxidant activities of barley extract. The highest contents of total phenolics and proanthocyanidins were obtained from extraction with 70% acetone. For three different solvent extracts, the antioxidant activities were in this order: 70% acetone extract > 70% ethanol extract ⩾ 70% methanol extract. Reducing powers of three extracts and their scavenging effects on 2, 2-diphenyl-1-picrylhydrazyl radicals were effective at amount of 200 μg. The 70% acetone extract of barley exhibited high antioxidant activity in linoleic acid system, which was not significantly ( P

Glutamate decarboxylase (EC 4.1.1.15, GAD) is a pyridoxal 5′-phosphate (PLP) dependent enzyme, which catalyses the irreversible α-decarboxylation of l -glutamic acid to γ-aminobutyric acid. GAD was purified 186-fold from rice germ using a combination of ammonium sulfate fractionation, DEAE-Sepharose FF ion exchange chromatography, Superdex-200 gel filtration chromatography, and Glu-Sepharose CL 4B affinity chromatography. The purified preparation showed a single peak on SE-HPLC with an approximate molecular mass of 78 kDa and a single band on SDS–PAGE with a subunit Mr of 40 kDa. This indicated that the GAD from rice germ existed as a dimer of homological subunits. Rice germ GAD has an optimum pH range between 5.5 and 5.8, and an optimum temperature at 40 °C. Km values for glutamic acid and PLP were determined at 32.3 mM and 1.7 μM, respectively. Chemicals reagents such as HgCl2, KI and AgNO3 decreased the enzyme activity by 68.5%, 44.9% and 32.4%, respectively, but 500 μM of CaCl2 at the optimum pH could increase the activity by 145%.

Protein fractions (albumin, globulin, prolamin and glutelin) were extracted from defatted tartary buckwheat flour. The in vitro pepsin digestibilities of the four protein fractions were different, and albumin was more susceptible to pepsin hydrolysis. The native structure of the four protein fractions may be destroyed by heat treatment, and the digestibilities were all improved significantly (P

Glutamate decarboxylase (EC 4.1.1.15, GAD) is a pyridoxal 5′-phosphate (PLP) dependent enzyme, which catalyses the irreversible α-decarboxylation of l -glutamic acid to γ-aminobutyric acid (GABA). GAD was purified 186-fold from rice germ. Ultraviolet–visible spectra showed that the rice germ holoGAD presented a weak peak at 420 nm, but the inactivated apoGAD did not. The holoGAD also exhibited a strong peak at 308 nm and a weak peak at 336 nm in its fluorescence emission spectrum. The apoGAD led to a 20% increase in the fluorescence emission at 308 nm. The contents of the secondary structure elements of the holoGAD and apoGAD were estimated from the values of the mean residue ellipticity based on the CD spectra. The holoGAD had a greater β-sheet content than the apoGAD (39% versus 27%), whereas both had a similar α-helix content (13% versus 14%). These findings confirmed that a slight conformational change had occurred when PLP bound to the apoGAD to form the holoGAD. Chemical modifications of the GAD by some selected reagents indicated that histidine residue(s) might be involved in the enzymatic functions, but were not essential for the enzyme activity. The study also suggested there was one arginine residue in the GAD active site, and most likely at the substrate-binding site.

Oat bran protein concentrate (OBPC) was prepared from oat bran, and hydrolyzed using trypsin. Protein hydrolysates of three different degrees of hydrolysis (4.1%, 6.4% and 8.3% respectively) were obtained. SDS-PAGE analysis demonstrated that oat globulin was the major protein component in OBPC. After trypsin treatment, acidic polypeptides were partly degraded into large peptides ( M r = 29,000–33,000) and small peptides ( M r

Antioxidant capacities of the essential oil extracted from parsley (Petroselinum crispum) were evaluated by three different in vitro assays: β-carotene bleaching assay, DPPH free radical scavenging assay and Fe2+-metal chelating assay. Results showed that the parsley oil (PO) possessed a certain degree of antioxidant activities in terms of β-carotene bleaching capacity and free radical scavenging activity, but its metal chelating capacity was negligible. The antioxidant EC50 values of the β-carotene bleaching assay and DPPH free radical scavenging assay of the crude PO dissolved in methanol were measured in about 5.12 and 80.21 mg/mL, respectively. However, these values were much weaker than those of BHT in 0.01 and 0.58 mg/mL, and of α-tocopherol in 0.01 and 0.10 mg/mL. Isolation and identification of the inherent antioxidants in PO involved using various chromatographic techniques including silica gel open column chromatography, normal phase-HPLC and GC–MS. Myristicin in PO was found as a dominant compound (32.75%) that exhibited a moderate antioxidant activity. Apiol was the second dominant compound (17.54%), but it might be the major contributor to the antioxidant activity of PO. These results suggest that the PO and its two major components can be potential alternative natural antioxidants.

The accumulation of gamma-aminobutyric acid (GABA) in the rice germ by using protease was investigated. After the proteolytic hydrolysis of germ protein by trypsin, the amount of GABA reached about 2.26 g per 100 g of germ. This demonstrates that the GABA yield could be significantly increased by protease. Our method is efficient and safe for manufacturing health food enriched with GABA.

Feruloyl oligosaccharides production from wheat bran insoluble dietary fibre was carried out using xylanases from Bacillus subtilis . Response surface methodology (RSM), based on a five level, five variable central composite rotatable design (CCRD), was employed to obtain the best possible combination of reaction temperature, pH, time, enzyme concentration and substrate (wheat bran insoluble dietary fibre) concentration for maximum feruloyl oligosaccharides production. The optimum reaction conditions were as follows:temperature, 42 °C; pH, 5.2; reaction time, 35 h; enzyme concentration, 4.8 g/l and substrate concentration, 120 g/l. Under these conditions, the experimental yield was 1.55 mM, which is well matched with the predictive yield.

Protein fractions (albumin, globulin, prolamin and glutelin) were extracted from defatted tartary buckwheat flour. Albumin was the predominant protein fraction (43.8%) followed by glutelin (14.6%), prolamin (10.5%), and globulin (7.82%). Albumin was relatively rich in histidine, threonine, valine, phenylalanine, isoleucine, leucine and lysine. Globulin had high levels of methionine and lysine. Prolamin was high in histidine, threonine, valine, isoleucine, and leucine. Glutelin was rich in histidine, threonine, valine, isoleucine, and leucine. SDS–PAGE analysis, under non-reductive and reductive conditions, showed that disulfide bonds existed in the four fractions. Non-reduced albumin showed major bands at 64, 57, 41, and 38 kDa, and globulin at 57, 28, 23, 19 and 15 kDa. Reduced albumin and globulin shared two common bands at 41 and 38 kDa. Reduced prolamin showed major bands at 29, 26, 17 and 15 kDa. In vitro pepsin digestibility of the four fractions (from high to low) was: albumin > globulin > prolamin and glutelin.

Water-soluble feruloyl oligosaccharides, which were released from wheat bran insoluble dietary fiber treated with xylanase from Bacillus subtilis and further purified with Amberlite XAD-2, were evaluated for their 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and their capacity in inhibition of rat erythrocyte hemolysis mediated by 2,2′-azobis-2-amidinopropane dihydrochloride (AAPH) under in vitro conditions. The EC 50 value of the water-soluble feruloyl oligosaccharides against the DPPH radical was 0.52 mg/ml. The oxidative hemolysis of rat erythrocytes induced by AAPH was suppressed by the water-soluble feruloyl oligosaccharides in a concentration- and time-dependent manner. The water-soluble feruloyl oligosaccharides, at a concentration of 4 mg/ml, showed 91.7% of inhibition of rat erythrocytes hemolysis, and the erythrocyte hemolysis could be retarded for more than 120 min. These data indicated that the water-soluble feruloyl oligosaccharides from wheat bran insoluble dietary fiber might have potential as natural antioxidants.

Insoluble dietary fiber from wheat bran contains some feruloyl groups linked to the arabinose residues in the cell wall arabinoxylan. Treatment of wheat bran insoluble dietary fiber with xylanase from Bacillus subtilis yielded feruloyl oligosacchairdes, which were purified with Amberlite XAD-2. Saponification of the feruloyl oligosaccharides released ferulic acid and arabinoxylan oligosaccharides which consist of arabinose and xylose. The effect of the feruloyl oligosacchairdes on the growth of Bifidobacterium bifidum F-35 was investigated in vitro. The B. bifidum produced acid when cultivated anaerobically in TPY broth with 0.5% feruloyl oligosacchairdes as the carbohydrate source. The biomass yield of the B. bifidum increased with increasing the concentration of feruloyl oligosaccharides in TPY broth. The maximum cell growth was increased by 50% in TPY broth supplemented with 0.1% feruloyl oligosaccharides compared to TPY broth. These results indicated that the growth of B. bifidum F-35 was promoted by the feruloyl oligosaccharides from wheat bran insoluble dietary fiber, and not suppressed by the ferulic acid moiety of them.

A novel and convenient method based on native polyacrylamide gel electrophoresis (PAGE) and homogenization extraction was used for the purification of xylanase from crude enzymes. Two xylanases were purified by this method from the crude enzyme preparation from the selected strain of Bacillus subtilis. Subsequent analysis with thin layer chromatography and high pressure liquid chromatography (HPLC) indicated that these two xylanases were endo-acting enzymes, designated xyl I and xyl II. Both enzymes showed their activities in the pH range from 5.0 to 9.0 at 50 °C and had similar optimum activities at pH 7.0 and at 50 °C. Mn2+ ions enhanced their xylanolytic activities to 2.7-fold whereas Fe3+ completely inhibited them. The action of endoxylanase xyl II on wheat bran insoluble dietary fibre was also studied. The hydrolysis products were shown to contain feruloyl oligosaccharides by paper chromatography.

Ferulic acid, the main phenolic acid in wheat bran, is esterified to arabinose residues in the cell wall arabinoxylan. Treatment of wheat bran insoluble dietary fibre with xylanases from Bacillus subtilis released feruloylated oligosaccharides, which were purified with Amberlite XAD-2. The antioxidant activity of such oligosaccharides was evaluated using the assay system for erythrocyte hemolysis mediated by peroxyl free radicals generated from 2,2 ′ -azobis-2-amidinopropane dihydrochloride (AAPH) under in vitro conditions. The feruloylated oligosaccharides inhibited hemolysis of erythrocytes in a dose-dependent manner with 91.7% inhibition of erythrocyte hemolysis at 4 mg/ml.

The effects of enzymatic treatment of corn gluten on the extraction of lutein and zeaxanthin (non-provitamin A carotenoids), which have multiple bio-functional properties in human beings, were studied. They were extracted from corn gluten meal (CGM) after pretreatment by protease (neutrase 0.5 L) under the following conditions: enzyme content 214 (U/g protein), solid content 15%, and hydrolysis time of 2 h. The yields of crude lutein, crude zeaxanthin, and total carotenoids were increased from 74.1, 77.1, and 393.6 to 113.5, 140.1, and 599.1 (µg/g, CGM on moisture-free basis), respectively.

TBWSP31 is a novel antitumor protein that was isolated from tartary buckwheat water-soluble extracts. The objective of this paper was to investigate the anti-proliferative effects of TBWSP31 on breast cancer Bcap37cells and to explore its possible mechanism. After treatment of Bcap37 cells with TBWSP31, typical apoptotic morphological changes were observed by inverted microscopy and scanning electron microscopy (SEM), such as detachment from the culture plate, change to a round shape, cell shrinkage, the absence of obvious microvilli, plasma membrane blebbing, and formation of apoptotic bodies. Cell-cycle analysis revealed that treatment with TBWSP31 resulted in a G(0)/G(1) arrest and prevented the cells from growing from G(0)/G(1) phase to S phase, which was most prominent at 48 h. The expression of bcl-2 and Fas were detected quantitatively by FCM, which showed that TBWSP31 induced-apoptosis may be involved with the participation of Fas and bcl-2. These results suggest that TBWSP31 is a potential antitumor compound and that apoptosis induced by TBWSP31 is a key antitumor mechanism.

A new multi-residue methodology using liquid chromatography-time-of-flight mass spectrometry (LC-TOF-MS) for the quantitative analysis of pesticides has been developed. The analytical performance of the method was evaluated by screening herbicide and insecticide residues in 10 kinds of imported soybeans. The accurate mass was obtained in different spiking levels (from 0.05 to 0.10 mg/kg) and the accuracy error was lower than 3 x 10(-6), which is well within the accepted limits for target confirmation. The linearity of response ranged from 0.03 mg/kg to 1.0 mg/kg and the correlation coefficient was greater than 0.99. The average recoveries of herbicides and insecticides ranged from 60% to 120% of the fortified herbicides and insecticides in soybeans at 0.05 - 0.10 mg/kg levels for the majority of herbicides and insecticides, and the relative standard deviations (RSD) were between 2.17% and 13.54%. The limits of detection (LOD) were between 0.002 and 0.026 mg/kg. The results indicated that the method developed is easier, faster, and more sensitive. It also demonstrated that this method can meet the requirements for simultaneous determination of herbicides and insecticides in soybeans. This study provides valuable evidence for that LC-TOF-MS method has the potential in screening multi pesticide residues in soybeans.

Wheat-bran ( Triticum aestivum L.) antifreeze protein ( TaAFP) was purified 323-fold to electrophoretic homogeneity with an overall yield of 1.64% from wheat-bran protein by a specific three-step procedure. The three-step procedure was quicker, cheaper, and more effective than the five-step procedure we used earlier. First, TaAFP was concentrated by a phosphate buffer, on the basis of its strong hydrophilicity that was validated by thermal gravimetric analyses and a surface hydrophobicity analysis. Second, TaAFP was trapped in ice crystals for its specific ice-binding capacity, which was proved by ice-binding protocols. Remarkably, the ice-binding step was the most effective step, and the purification factor of this step was up to 270-fold. Finally, TaAFP was purified by HPLC purification, a complementary step for the specific ice-binding protocol, to electrophoretic homogeneity. Our protocols provide peers a novel and effective way for the search and purification of potential AFPs.

The antifreeze ability of glutathione was evaluated on the basis of its thermodynamic characteristics and protection of baker's yeast during cryopreservation at −30 °C. The thermodynamic characteristics and protection of baker's yeast of glutathione were similar to those of known antifreeze proteins, such as carrot antifreeze protein and holly antifreeze protein. These properties included lowering the freezing point at about 0.20 °C non-colligatively, decreasing freezable water content, controlling the movement of free water for its strong hydrophilicity, and improving baker's yeast survival during the simulated processing of frozen dough. Therefore, glutathione was viewed to be an antifreeze protein like substance on the basis of its unique thermodynamic characteristics and protection of baker's yeast. The method combining thermodynamic characteristic analysis and protection evaluation is a new and simple way to screen new antifreeze proteins. Keywords: Antifreeze protein; glutathione; thermodynamic char...

Lutein and zeaxanthin have various activities such as anti-age-related macular degeneration, anticataract, anticancer and cardiovascular diseases risk lowering, etc.; however, few studies have been reported on the role of free hydroxyl groups in the antitumor effects of lutein and zeaxanthin. The structure-activity relationship (SAR) of lutein and zeaxanthin di-acetylation derivatives has been investigated. The lutein and zeaxanthin were purified from corn protein residues and structurally modified by di-acetylation, which was characterized with UV/visible and HPLC/MS spectroscopy. The anti-proliferative effects of di-acetylated lutein or zeaxanthin on the human mouth epithelial cancer line KB cell were compared with controls of their original counterparts. Results showed that the anti-tumor activities of the di-acetylation of lutein and di-acetylation of zeaxanthin decreased significantly (p0.05) at 50 micromol/L. Also the related IC50 dose was increased after di-acetylation. It was suggested that the hydroxyl groups contribute to the anti-tumor activity of lutein and zeaxanthin.

This paper presents to make use of visualization technique to study the process of extrusion and extrusion assembly, the visual phenomena indicate that material transportation underlying the extrusion course is a combination of two transportations, one is positive displacement pumping transportation in the intermeshing region, and the other is partially filled transportation in the translation region. Virtual assembly technique is used to design the extrusion assembly, and interference is checked, and animations are created to demonstrate assembly sequence and path. This product has been designed successfully by computer in virtual environment.

Hypoglycemic polypeptide (PA) was extracted from Momordica charantia seeds with organic acid and ethanol and purified with Sephadex G-50 gel filtration and RP-HPLC. PA was judged as plant insulin on the base of the analysis of its SDS-PAGE electrophoresis and amino acid composition.