Free radical-scavenging capacity and inhibitory activity on rat erythrocyte hemolysis of feruloyl oligosaccharides from wheat bran insoluble dietary fiber

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 EC₅₀ 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.     

草酸蒸煮处理和表面活性剂对酶法制备低聚糖阿魏酸酯的影响

低聚糖阿魏酸酯兼具低聚糖的益生菌增殖活性和阿魏酸的抗氧化活性,可通过水解阿拉伯木聚糖获得。本文采用阿魏酸含量最高的玉米皮为原料,研究草酸蒸煮处理和添加表面活性剂对酶解玉米皮制备低聚糖阿魏酸酯的影响。研究结果显示:草酸含量0.6%,料液比1:10(W:V),0.1MPa蒸煮20min后,采用木聚糖酶酶解可获得阿魏酸含量为14.10mg/g的低聚糖阿魏酸酯,并将玉米皮中52.2%的阿魏酸游离出来。酶解过程中,添加表面活性剂Tween-80、Tween-20和Span-80,能显著提高玉米皮的酶解效率。当3者添加量分别为4%、3%和2%时,低聚糖阿魏酸酯中阿魏酸含量分别提高到190%、128%和152%。使用Span-20可降低阿魏酸酯产量。     

发酵麦麸阿魏酰低聚糖的纯化工艺及其心脏保护作用研究

以发酵麦麸阿魏酰低聚糖( Feruloylated oligosaccharides, FOs)粗提液为原料,研究Amberlite XAD-2 大孔吸附树脂结合Sephadex LH-20 葡聚糖凝胶对发酵麦麸FOs的纯化工艺和效果,同时考察分离纯化后发酵麦麸 FOs对斑马鱼心脏损伤的保护作用。结果表明：Amberlite XAD-2 大孔吸附树脂分离发酵麦麸FOs的最佳吸附条件为：上样液浓度4.0 mg /mL,上样液pH 4.0,上样体积40 mL,在此条件下吸附率可达83.76%;最佳的解吸条件为：乙醇浓度50%、洗脱体积15 mL,在此条件下解吸率可达94.80%。Sephadex LH-20 葡聚糖凝胶进一步纯化发酵麦麸FOs的最佳条件为：洗脱剂乙醇浓度25%,上样量1.25 mL,洗脱流速 0.3 mL/min,在此条件下,分离出的组分最多;紫外光谱分析表明纯化发酵麦麸 FOs中有阿魏酸的存在;纯化后发酵麦麸 FOs含量由粗提液的（1107.796 ± 52.18）nmol/g提高到（2217.38 ± 25.36 ）nmol/g,提高了2倍,纯化效果较佳;此外,经分离纯化后发酵麦麸FOs能有效缓解特非那定诱导的斑马鱼心率和降低斑马鱼心脏SV-BA间距,表明分离纯化后发酵麦麸 FOs具有良好的心脏保护作用。     

低聚糖阿魏酸酯含量的快速测定方法

分别以麦麸、玉米芯、玉米麸皮为原料,采用酶法制备低聚糖阿魏酸酯,探讨其快速检测方法,并通过高效液相色谱法验证该法的准确性。结果表明,采用Amberlite 树脂分离纯化可除去样品中的低聚糖(不含结合态的阿魏酸)、双波长分光光度法(345nm 和375nm)结合还原糖法可用于对低聚糖阿魏酸酯进行准确定量。     

酸解制备低聚糖阿魏酸酯的优化工艺研究

采用稀盐酸水解玉米麸皮制备低聚糖阿魏酸酯(FOs),以FOs的量为指标,研究了液料比、酸浓度、温度、时间和提取次数5个因素对酸解效果的影响,并在此基础上,通过中心组合试验对工艺进行了优化。结果表明,稀盐酸水解玉米麸皮提取FOs的最佳工艺条件是液料比为15∶1(mL/g),酸浓度为0.05 mol/L,温度为100℃,时间为4 h,提取次数为2次,在此条件下,FOs平均含量可达每克麸皮4.66×10-5mol。     

对香豆酸、阿魏酸和低聚糖阿魏酸酯对酪氨酸酶的抑制效果

通过测定酶的稳态活力、迟滞时间和动力学参数,研究对香豆酸、阿魏酸及低聚糖阿魏酸酯对酪氨酸酶的抑制效果。结果表明,3种物质对酪氨酸酶单酚酶活性均有抑制作用,其中对香豆酸的抑制作用最强,其次为低聚糖阿魏酸酯和阿魏酸。对香豆酸、低聚糖阿魏酸酯和阿魏酸对单酚酶的IC_(50)值分别为0.75,3.20,9.30 mmol/L。对香豆酸和阿魏酸抑制二酚酶活性,IC_(50)值分别为4.3,12.7mmol/L;但低聚糖阿魏酸酯对二酚酶活力没有影响。对香豆酸能明显延长单酚酶反应的迟滞时间,阿魏酸影响很小,而低聚糖阿魏酸酯则缩短迟滞时间。动力学研究结果显示,阿魏酸和低聚糖阿魏酸酯对单酚酶的抑制作用表现为混合性抑制,而对香豆酸为竞争性抑制。     

黑小麦功能性低聚糖的分离与组成分析

研究黑小麦麸皮功能性低聚糖的分离制备方法,并对其组成进行分析。采用木聚糖酶酶解黑小麦麸皮不溶性膳食纤维,所得酶解液经活性炭柱层析进行分离,并利用液相色谱和离子色谱对分离组分的单糖组成、低聚糖组成以及阿魏酰基团进行检测。结果表明,活性炭柱层析的水洗组分(WO)、不同浓度醇洗组分(EO)的低聚糖均主要由阿拉伯糖和木糖组成,为阿拉伯低聚木糖。其中,WO含有结合态阿魏酸,为阿魏酰低聚糖。WO的低聚糖聚合度较高,为DP 4~7;醇洗组分EO的低聚糖聚合度较低,为DP 2~4。     

玉米皮阿拉伯糖阿魏酸酯体外抗氧化活性的研究

本文采用稀盐酸水解玉米麸皮得到低聚糖阿魏酸酯（FOs）,经D301大孔树脂的除杂和聚酰胺柱层析的分离获得FOs中的F-Ara组分,在分析结构后,对该组分进行了体外清除DPPH和超氧阴离子自由基的能力测定和还原力测定。结果表明,与标准物阿魏酸（FA）、BHA和维生素C相比,F-Ara均表现出良好的体外清除自由基活性,其活性随浓度的增加而增大;在试验浓度为0.6 mmol/L时,与标准物阿魏酸和维生素C相比,F-Ara显示出最高的还原值,说明F-Ara具有较强的还原力。以上结果揭示F-Ara可成为一种能应用到食品、药品和化妆品的天然高效的抗氧化剂。     

微波处理对小麦麸皮酶法制取低聚木糖的影响

研究一种高效、无污染、低成本的以小麦麸皮为原料酶法制备低聚木糖的方法.分别考察酸法、碱法、双氧水法处理小麦麸皮,比较经微波处理与不经微波处理的小麦麸皮中木聚糖的得率.结果表明:不经微波处理的麸皮的木聚糖提取率最高的是双氧水法处理;经微波处理后木聚糖提取率最高的是碱法处理;TLC(薄层色谱)结果显示小麦麸皮酶解液的主要成分为木二糖.     

An Attempt to Identify the Low Molecular Feruloylated Oligosaccharides in Beer

Ferulic acid (4‐hydroxy‐3‐methoxycinnamic acid), predominantly in ester form in arabinoxylan chains, is the main phenolic acid present in barley and malt. Only about 1% of the total ferulic acid in barley is present in the free form. A number of previous works concerned the contents of free and esterified ferulic acid in a broad range of popular beers, but there is little information about the possible composition of feruloylated oligosaccharides in beers. The aim of this preliminary work was to purify the feruloylated oligosaccharides from lager beers (by the means of preparative chromatography) followed by composition elucidation using TLC, HPLC with RI or UV detection and ¹H‐NMR. Indeed, the qualitative analyses of isolated fractions from beer revealed that the fractions contained ferulic acid in the ester form (as proven after mild alkaline hydrolysis). It was also shown that molecular masses of oligosaccharides present in the purified beer fractions were similar to the masses of arabinose and xylooligosaccharides in the range of xylose to xylohexaose. Although a number of purified beer samples contained oligosaccharides of higher molecular masses, these were not further characterized. Taking under consideration the presented results, it can be concluded that beer can be a good source of feruloylated oligosaccharides, significant in the context of human health benefits.     

麦麸阿魏酸糖酯微生物发酵工艺优化及体外抗氧化和益生活性评价

以麦麸为原料,对固态发酵制备麦麸阿魏酸糖酯（Feruloylated glycosides,FGs）的工艺进行优化,并对其体外抗氧化及益生活性进行评价。以植物乳杆菌、枯草芽孢杆菌、地衣芽孢杆菌、酿酒酵母为发酵菌种,采取单菌发酵和混菌发酵筛选最优菌种组合,考察接种量、发酵温度、发酵时间、料水比对麦麸FGs产量的影响,通过响应面试验设计优化发酵工艺。结果表明:以枯草芽孢杆菌:地衣芽孢杆菌:酿酒酵母=1:1:1发酵麦麸时,FGs产量最高;最佳固态发酵工艺条件为发酵温度42.5℃,发酵时间58.5 h,接种量10.7%,料水比1:1.16（g/mL）,在此条件下FGs产量为1273.18 nmol/g;抗氧化实验结果表明,DPPH自由基清除率高达87.42%（1 mg/mL）,羟基自由基清除率为33.68%（4 mg/mL）,还原力为1.078（4 mg/mL）。发酵麦麸FGs可有效促进嗜热链球菌和植物乳杆菌的增殖。综上所述,以枯草芽孢杆菌、地衣芽孢杆菌和酿酒酵母混菌发酵制备的麦麸FGs有一定的抗氧化和益生活性。     

Association of non-starch polysaccharides and ferulic acid in grain amaranth (Amaranthus caudatus L.) dietary fiber

The association of ferulic acid, an alkali-extractable phenolic acid in amaranth (Amaranthus caudatus L., Amaranthaceae) insoluble fiber (trans-ferulic acid: 620 microg.g-1, cis-ferulic acid: 203 microg.g-1), and non-starch polysaccharides was investigated. Enzymatic hydrolysis of insoluble amaranth fiber released several feruloylated oligosaccharides that were separated using Sephadex LH-20-chromatography and reversed phase-high performance liquid chromatography (RP-HPLC). Three compounds were unambiguously identified: O-(6-O-trans-feruloyl-beta-D-galactopyranosyl)-(1-->4)-D-galactopyranose, O-(2-O-trans-feruloyl-alpha-L-arabinofuranosyl)-(1-->5)-L-arabinofuranose, and O-alpha-L-arabinofuranosyl-(1-->3)-O-(2-O-trans-feruloyl-alpha-L-arabinofuranosyl)-(1-->5)-L-arabinofuranose. These feruloylated oligosaccharides show that ferulic acid is predominantly bound to pectic arabinans and galactans in amaranth insoluble fiber. 5-O-trans-Feruloyl-L-arabinofuranose was the only compound isolated in pure form from an acid hydrolyzate. This compound may have its origin from pectic arabinans but also from arabinoxylans.     

On-line separation and structural characterisation of feruloylated oligosaccharides from wheat bran using HPLC-ESI-MS

Water-soluble feruloylated oligosaccharides (FOs) from wheat bran, ferulic acid esters of arabinoxylan oligosaccharides, have been reported as natural antioxidants. In this study, structure features of FOs were studied by FT-IR spectroscopy, and high-performance liquid chromatography (HPLC) coupled to electrospray ionisation (ESI) mass spectrometry (MS) was used for separation and characterisation of FOs. Four components of FOs were resolved on a Dikma Technologies Diamonsil™ C₁₈ column eluted with water/acetonitrite (90:10) containing 0.5% HCOOH (V/V) and further analysed by ESI-MSⁿ. In ESI-MSⁿ, a predominant [M+NH₄]⁺ ion in positive mode and [M−H]⁻ ion in negative mode were observed for molecular mass information. The ESI-MSⁿ spectra of the deprotonated molecular [M−H]⁻ ion were used for structural elucidation. The structures of four isolated compounds were confirmed for the first time by on-line HPLC-ESI-MSⁿ.     

麦麸阿魏酸低聚糖酯组分的结构表征及其对美拉德反应产物抑制作用研究

对麦麸中阿魏酸低聚糖酯组分（F3）进行结构表征及其对美拉德反应产物抑制作用研究。分别采用紫外可见光谱法、高效液相色谱法（HPLC）、气相色谱法（GC）、红外光谱法（IR）进行结构表征,结合平均相对分子质量法分析组分F3的组成;HPLC法检测组分F3对美拉德反应中间产物α-二羰基化合物的抑制作用。结构分析可知组分F3为阿魏酸通过酯键连接在阿拉伯木糖糖体上的糖酯结构;相对平均分子质量为781.429 ± 13.774 u,可能为阿魏酰阿拉伯糖基木三糖（FA-ara-(xly)3）;组分F3可有效抑制美拉德反应中间产物丙酮醛（MGO）、乙二醛（GO）和2, 3-丁二酮（2, 3-BD）的生成,并呈浓度依赖关系。在50 mg/mL浓度时其抑制率分别为（81.46 ± 4.69）%、（68.24 ± 0.16）%和（54.89 ± 2.25）%,均优于FA的抑制效果。因此,组分F3具有良好的抑制美拉德反应中间产物作用。     

采用浓硝酸和酶处理后麦麸成分的变化规律研究

麦麸是一种典型的木质纤维素类生物质.本文研究了应用85%的浓硝酸和酶对麦麸进行前期处理和糖化处理之后的成分变化规律.结果表明,在50℃以下温度和60 min的处理时间之内,提高浓硝酸处理温度或者延长处理时间均有利于原料水溶部分质量比例的提高;有利于水溶部分中木糖,阿拉伯糖、葡萄糖等糖类成分含量的增加;有利于高分子量的碳...     

Inhibitory effect of wheat bran feruloyl oligosaccharides on oxidative DNA damage in human lymphocytes

The present work assessed the protective effect of feruloyl oligosaccharides (FOs), the ferulic acid ester of oligosaccharides from wheat bran, against oxidative DNA damage in normal human peripheral blood lymphocytes induced by hydrogen peroxide (H₂O₂). The DNA damage was measured by using the single cell gel electrophoresis assay (comet assay). Lymphocytes were subjected to DNA damage by exposure to a range of H₂O₂ concentrations (10–200 μmol/l). H₂O₂, at a concentration of 200 μmol/l, resulted in nearly all cells being highly damaged. FOs showed no cytotoxicity and genotoxicity to normal human lymphocytes at the tested concentrations (10–500 μmol/l). In addition, DNA damage in human lymphocytes induced by 100 μmol/l H₂O₂ was inhibited by FOs in a concentration-dependent fashion with 91.1% inhibition of lymphocyte DNA damage at 500 μmol/l as compared with the control. The results suggest that water-soluble FOs from wheat bran are able to enhance the ability of human lymphocytes to resist H₂O₂ induced oxidative damage.     

黑小麦麸皮酚酸物质的定性分析与阿魏酸含量测定

对黑小麦麸皮中的主要酚酸物质进行制备和定性分析,并测定阿魏酸含量。采用乙醇和氢氧化钠溶液处理黑小麦麸皮,提取样品中的游离态酚酸(free phenolic acids,FPA)和结合态酚酸(conjugated phenolic acids,CPA)。通过液质联用(LC/MS)和紫外光谱(UV)等方法对提取的酚酸物质进行定性分析。紫外光谱显示,游离态和结合态酚酸具有与阿魏酸相似的分子结构。LC/MS检测结果显示,游离态和结合态酚酸的相对分子质量分别为224和194。由此判断黑小麦麸皮中的游离态酚酸FPA主要为芥子酸,结合态酚酸CPA主要为阿魏酸。采用高效液相色谱(HPLC)对黑小麦麸皮中的结合态阿魏酸含量进行测定。结果表明,紫粒黑小麦麸皮的阿魏酸含量为2.07 mg/g,与蓝粒黑小麦麸皮的阿魏酸含量(2.12 mg/g)相近,其含量高于当地种植的普通小麦麸皮的阿魏酸含量(1.17 mg/g)。     

阿魏酸低聚糖的体外抗氧化性质的研究

采用羟基自由基、超氧阴离子、DPPH自由基、还原力、脂质体氧化反应体系，检测了阿魏酸低聚糖的体外抗氧化海洼。结果表明阿魏酸低聚糖有较强的抗氧化活性，是一种良好的天然抗氧化剂。     

Aleurone cells are the primary contributor to arabinoxylan oligosaccharide production from wheat bran after treatment with cell wall-degrading enzymes

Arabinoxylans and in particular arabinoxylan oligosaccharides (AXOS) from wheat are recognised for their prebiotic potential. A high-yield, non-chemical production of AXOS is therefore of interest when producing functional foods. This study investigated the enzymatic production of AXOS from wheat bran with the aim of establishing the main fraction contributing to production of AXOS. Fractions of wheat bran, outer pericarp and aleurone with two different purities were treated with the cell wall-degrading enzymes: xylanase, cellulase and β-glucanase. The yield of solubilised arabinoxylans upon treatment was greatest in the most pure aleurone fraction (164 g kg⁻¹) and lowest in the outer pericarp fraction (15 g kg⁻¹). The yield was mainly recovered as AXOS rather than soluble arabinoxylans and was negatively related to the arabinose/xylose ratio found in the raw material. In conclusion, wheat aleurone cell walls are the main contributor to the production of AXOS from wheat bran and this seems to depend on the A/X ratio of the raw material.     

诱导物对出芽短梗霉木聚糖酶活力和阿魏酰低聚糖合成的调控影响

以麦麸为原料诱变选育的不产黑色素出芽短梗霉为发酵菌株,利用其发酵过程中合成的木聚糖酶水解麦麸纤维,制备阿魏酰低聚糖(FOs)。研究碳源、氮源、金属离子和表面活性剂等诱导物对出芽短梗霉木聚糖酶活力和FOs合成的影响,以探明各物质对出芽短梗霉木聚糖酶活力和FOs合成的影响;利用正交试验设计方法研究各物质添加量对出芽短梗霉产酶和FOs的影响,确定芽短梗霉发酵制备FOs的最佳培养基。结果表明:50g/L麦麸处理液中添加15g/L葡萄糖、1g/L蛋白胨和1g/L玉米浆,FOs产量和木聚糖酶活力最高分别达到627nmol/L和52.66IU/mL。