超声波辅助提取小麦麸皮酚基木聚糖的研究

以小麦麸皮为原料,研究了超声波超声功率、超声时间、碱液质量分数、碱提时间、碱提温度对小麦麸皮中水溶性酚基木聚糖和总酚基木聚糖得率的影响,同时分析了小麦麸皮水溶性酚基木聚糖的抗氧化特性和总酚含量.结果表明,小麦麸皮中酚基木聚糖提取的最佳工艺条件是超声功率300 W,超声时间30 min,碱液质量分数2％,碱提时间2h,碱提温度55℃,在此条件下,酚基木聚糖得率为38.73％,水溶性酚基木聚糖得率为29.05％.对提取的麸皮水溶性酚基木聚糖的抗氧化性的研究表明,水溶性酚基木聚糖对羟自由基有明显的清除作用,并呈现明显的量效关系.水溶性酚基木聚糖的总酚含量为12.27mg/g.     

小麦麸皮木聚糖制备方法的研究

研究了小麦麸皮木聚糖的制备,借助高速粉碎处理的方法分离麸皮中淀粉,再采用胶体磨与纤维素酶处理及碱浸泡处理,回收蛋白质,最后通过优化确定最佳低聚糖的最佳工艺。试验结果显示粉碎时间2 min,试验原料的粒径范围为125μm,淀粉得率72.43%;纤维素酶和碱处理的最佳工艺条件为:加酶量1.0 m L/hg,碱处理温度为60℃,碱处理p H为9.5,在此条件下木聚糖质量分数为35.5%,蛋白质提取率为74.9%,水洗的最佳水洗次数为4次,此时木聚糖质量分数为36.5%。     

超声波对小麦麸皮木聚糖的提取效果影响

麸皮是小麦加工过程中的副产品,含有丰富的具有生物活性的木聚糖。为了充分提高小麦麸皮的附加值,采用超声波法萃取其中的木聚糖。讨论了碱液浓度、液固比、超声功率、超声时间和温度对木聚糖提取率的影响,在此基础上进行正交试验分析。结果表明:在液固比25∶1(m L/g),Na OH溶液浓度0.5 mol/L,超声功率240 W,超声时间35 min和超声温度50℃条件下,可以获得提取率高达44.8%的麸皮木聚糖。利用超声波法提取小麦麸皮木聚糖成低、能耗小和效率高,具有重要的应用价值。     

高温蒸煮法与微波法处理玉米芯制备低聚木糖比较

通过对高温蒸煮法和微波法处理玉米芯制备低聚木糖的比较，碍出：高温蒸煮法产物复杂，玉米芯经稀酸浸泡后再高温蒸煮，木聚糖提取率和水解液中还原糖含量均较高，但产物主要是单糖；微波法产物较单一，玉米芯经稀碱液浸泡后再微波处理，木聚糖提取率和水解液中还原糖含量均高，且其主要成分是木二糖，糠醛含量少。比较2种预处理方法，微波处理玉米芯制备低聚木糖更理想。     

小麦麸皮木聚糖理化性质及抗氧化活性研究

小麦麸皮是天然可再生的农业副产品,其中木聚糖是小麦麸皮中非淀粉多糖的主要成分,具有优良的理化特性和生理活性;但小麦麸皮多作为醋、酱油或饲料等其他廉价产品的原料,造成了资源浪费.通过对小麦麸皮高温蒸煮液进行乙醇分级沉淀,得到4种木聚糖组分(EXy40、EXy60、EXy80、EXy90),对各组分进行单糖组成分析、相对分子质量测定、红外光谱分析;考察了酶解对4种木聚糖组分体外抗氧化活性的影响.结果表明:4种木聚糖组分的相对分子质量分布较窄,多分散性系数较小;经改性后,体外抗氧化活性均有显著增强,其中EXy40、EXy80和EXy90三种组分的羟自由基清除率达到97％以上.研究以期为小麦麸皮的综合开发利用及深入探索小麦麸皮木聚糖的构效关系,提供一定的理论依据.     

小麦制粉产物中阿糖基木聚糖的制备及其分子特性研究

以小麦为原料,研究了小麦麸皮、小麦次粉和小麦粉中阿糖基木聚糖的得率、单糖组成、阿拉伯糖与木糖质量比、分子量和分子量分布等性质。结果表明:小麦麸皮、小麦次粉和小麦粉的阿糖基木聚糖得率分别为8.99%、7.28%和1.12%,其单糖组成主要为阿拉伯糖和木糖。小麦麸皮中的阿糖基木聚糖具有较低的阿拉伯糖与木糖比,表明其直链较少。HPSEC分析结果表明小麦粉阿糖基木聚糖分子量最高,而麸皮阿糖基木聚糖分子量最低。动态光散射分析得出三种阿糖基木聚糖水溶液的粒度大于其碱性溶液粒度,表明阿糖基木聚糖在不同的溶液中具有不同的聚合度。对三种阿糖基木聚糖进行回收率分析显示,1.0 M NaOH溶液可作为阿糖基木聚糖的良好溶剂,而水作为溶剂效果较差。综上所述,小麦麸皮、小麦次粉可作为阿糖基木聚糖的有效资源。     

响应面法优化稻壳中木聚糖的提取工艺

为提高稻壳中木聚糖的提取率,稻壳经3％的硫酸预处理后再用碱法进行木聚糖的提取,采用响应面法优化工艺条件,先对提取温度、NaOH浓度、固液比、提取时间4个因素进行单因素试验.根据单因素试验结果设计中心组合试验,以木聚糖提取率为考察指标,采用响应面分析法确定最优工艺参数.结果表明:提取温度69.8℃、NaOH浓度10.7％、固液比1∶13(m∶V)、提取时间5.1h.该条件下,木聚糖提取率可达76.57％.     

小麦麸皮阿拉伯木聚糖/豌豆分离蛋白复合物的乳化性能研究

通过碱溶醇沉法从小麦麸皮中提取小麦麸皮阿拉伯木聚糖(wheat bran arabinoxylan,WBAX).为扩大WBAX在乳液中的应用,向WBAX中添加豌豆分离蛋白(pea protein isolate,PPI),并对WBAX及添加PPI后的WBAX进行热处理(90℃,3 h),分别得到4种乳化剂.其中WBAX...     

响应面法优化黑小麦麸皮蛋白提取工艺研究

以黑小麦麸皮为原料,将超声波应用于碱法提取黑小麦麸皮蛋白中,提高黑小麦的深入开发水平.采用考马斯亮蓝法考察超声波功率、温度、pH以及时间等因素对黑小麦麸皮蛋白提取率的影响.通过单因素和响应面试验得出提取黑小麦麸皮蛋白的最佳条件:超声波功率350 W、温度55 ℃、pH 9.3、时间80 min.在此条件下,蛋白质提取率...     

木聚糖提取优化及对木聚糖酶活性的影响

以小米糠为试验原料,研究小米糠中木聚糖的提取工艺及对肠道木聚糖酶活力的影响。在单因素的基础上,采用正交试验优化小米糠木聚糖提取工艺,研究料液比、碱提温度、碱液浓度、碱提时间4个因素对提取木聚糖提取率的影响。并采用着色木聚糖标记法测定木聚糖酶活力,研究小米糠木聚糖对大鼠肠道粪便及消化道木聚糖酶活力的影响。结果表明,小米糠木聚糖的最佳提取工艺:料液比为1∶25(g/mL),碱处理温度为100℃,碱液浓度为10%,碱处理时间为2 h,在此条件下木聚糖提取率为21.71%。     

不同麦类麸中无机元素的含量分析

建立电感耦合等离子体发射光谱(inductively coupled plasma-optical emission spectrometry,ICP-OES)法测定荞麦麸皮、燕麦麸皮和黑麦麸皮中14种无机元素的分析方法。选择硝酸+过氧化氢为消解溶剂,麦类麸皮经微波密闭消解后直接分析。通过优化ICP-OES工作条件以及选择待测元素分析波长,确保仪器处于最佳工作状态,研究共存元素的光谱干扰及其消除。方法的检出限在0.26~52.66μg/L范围内;各元素的线性相关系数在0.999 5~0.999 9之间;通过测定国家标准物质小麦(GBW10011),表明方法具有良好的准确性和较高的精密度。     

Utilisation of corn (Zea mays) bran and corn fiber in the production of food components

The milling of corn for the production of food constituents results in a number of low‐value co‐products. Two of the major co‐products produced by this operation are corn bran and corn fiber, which currently have low commercial value. This review focuses on current and prospective research surrounding the utilization of corn fiber and corn bran in the production of potentially higher‐value food components. Corn bran and corn fiber contain potentially useful components that may be harvested through physical, chemical or enzymatic means for the production of food ingredients or additives, including corn fiber oil, corn fiber gum, cellulosic fiber gels, xylo‐oligosaccharides and ferulic acid. Components of corn bran and corn fiber may also be converted to food chemicals such as vanillin and xylitol. Commercialization of processes for the isolation or production of food products from corn bran or corn fiber has been met with numerous technical challenges, therefore further research that improves the production of these components from corn bran or corn fiber is needed. Published 2010 by John Wiley & Sons, Ltd.     

干酪乳杆菌(HN-2)固态发酵培养基的优化

该研究选择一株具有水质净化能力的干酪乳杆菌(Lactobacillus casei HN-2),以麸皮及米糠为主要基质对其开展了固态发酵研究。通过部分因子析因试验设计及响应面分析,获得了最佳的固体培养基组合,包括:麸皮6.87g、米糠9.84g、葡萄糖0.26g、大豆蛋白胨0.10g、MgSO4.7H2O 0.05g、CaCO30.25g、K2HPO4.3H2O 0.10g。当初始湿度为65%、初始pH值为6.0时,在37℃经过48h的固态发酵,干酪乳杆菌HN-2的菌体密度最大可达2.47×1010cfu/g。     

Antioxidant activity of feruloylated oligosaccharides from wheat bran

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.     

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。     

Phytate Hydrolysis by Phytase in Cereals; Effects on In Vitro Estimation of Iron Availability

Phytate (inositol hexaphosphate) hydrolysis by endogenous and exogenous phytases was studied for their effect on increasing iron availability in cereals. Wheat bran and whole meal flours of rye and oats were soaked at optimal conditions for phytase activity (55°C, pH 5) for different time intervals. Phytate and its degradation products were determined by HPLC and related to iron solubility under simulated physiological conditions. Small amounts of phytate (< lμmol/g) had a strong negative effect on iron solubility. When inositol hexa- and pentaphosphates of wheat bran and rye flour were completely hydrolyzed by activating endogenous phytase, iron solubility under simulated physiological conditions increased from 3 to 53% (wheat) and 5 to 21% (rye). Addition of wheat phytase to uncooked oatmeal increased iron solubility from 4 to 11 and in precooked to 18%, while endogenous phytase of uncooked oatmeal had less effect on phytate digestion and iron solubility.     

微波联合酶法对小麦麸皮品质改良及结构特性影响

本研究以小麦麸皮为原料,采用正交实验优化微波联合酶解对小麦麸皮品质改良工艺参数,并对比分析微波、酶解、微波联合酶解三种处理方式对小麦麸皮结构和性质的影响。研究发现:小麦麸皮微波联合酶解的最佳工艺参数为:微波功率700 W,时间15 min,料水比1:4,木聚糖酶添加量0.4 g,纤维素酶添加量0.4 g,酶解时间4 h,酶解温度60 ℃,此时小麦麸皮中还原糖含量为25.15 mg/mL。小麦麸皮经微波联合酶解处理后,持水性增加了30.18%,植酸含量降低了70.46%,持油性降低了26.69%,脂肪酶(LA)残余酶活降低至6.13%,粗纤维含量降低至2.79%,还原糖含量上升至25.15 mg/mL。傅里叶变换红外光谱分析结果表明微波联合酶解可以破坏分子间的糖苷键,使小麦麸皮细胞壁中纤维素、半纤维素降解,生成小分子的还原糖。扫描电子显微镜观察结果显示微波联合酶解破坏了小麦麸皮结构,使得麸皮表面变粗糙,结构疏松多孔。通过本实验改性的麦麸中脂肪酶残余酶活显著下降,麦麸食用品质明显改善。     

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。     

小麦麸皮酶法制备低聚糖的研究

以小麦麸皮为原料采用生物技术制备新型低聚糖,低聚糖含量可达８０％,对双歧杆菌增殖效果明显,具有多功能特性,生产成本低,工业化经济效益十分明显。     

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.