酶法提取杜仲叶活性成分的研究

本研究以杜仲叶为原料,通过添加复合酶制剂来提取活性成分,运用正交试验找出复合酶制剂的最佳配比。结果表明:杜仲叶粉碎为40～80目是活性成分提取效果和过滤难度间的平衡点;正交试验表明影响提取效果的因素主次为蛋白酶纤维素酶单宁酶果胶酶;添加蛋白酶0.18%、果胶酶0.03%,纤维素酶0.20%、单宁酶0.05%时,杜仲叶绿原酸浸出量为41.28 mg/g,是对照组的1.69倍。复合酶处理后的杜仲叶提取液为黄绿色,有杜仲叶特有的清香味、无青味,口感柔和无涩味,为杜仲叶的深加工提供理论基础。     

酶技术对红枣汁提取效果的影响

以红枣为原料,采用酶解浸提的方法制备红枣汁.主要研究酶解条件对红枣汁提取效果的影响,通过试验比较采用果胶酶、果胶酶与纤维素酶的复合酶、果胶酶与酸性蛋白酶的复合酶分别进行酶解浸提对红枣汁黏度和提取率的影响.试验表明:采用果胶酶与纤维素酶的复合酶时提取效果较好,在加酶量为果胶酶0.20%、纤维素酶0.15%;酶解温度T=50℃;浸提时间为t=3 h;料水比为1:5(g/mL)的条件下,提取率为60.2%,黏度为1.50mPa·s,所得汁液枣香浓郁、无苦味、颜色为枣红色,具有较好的稳定性.     

不同酶处理对小麦胚芽油提取率的影响

研究不同酶处理对小麦胚芽油提取率的影响,确定最佳水酶法提取小麦胚芽油工艺。选用纤维素酶、半纤维酶、酸性蛋白酶、淀粉酶、果胶酶作为提取酶,对小麦胚芽进行酶解,研究了不同酶处理对提油率的影响。单一酶处理试验中,分别用纤维素酶和酸性蛋白酶处理的提油率较高;复合酶处理试验中,酸性蛋白酶和纤维素酶组合处理的提油率最高;且复合酶处理比单一酶处理的提油率高。经过正交试验得出小麦胚芽油水酶法最优提取工艺为:复合酶(酸性蛋白酶∶纤维素酶=5∶1),酶解pH=5,酶解温度45℃。经验证试验小麦胚芽提油率可达到65.53%。试验提取的小麦胚芽油不饱和脂肪酸含量高达82%以上,营养品质较好。     

水酶法提取棕榈油的工艺研究

从纤维素酶、半纤维素酶、果胶酶、酸性蛋白酶等7种常用水解酶中,筛选出最适水解酶后,利用单因素实验和正交实验确定该酶提取棕榈油的最佳工艺参数,并对所得油脂中的酸价进行测定。结果表明:纤维素酶是提取棕榈油的最佳用酶,pH和酶解温度对棕榈油提取率的影响不显著;纤维素酶提取棕榈油的最佳工艺为pH4.5、酶解温度45℃、酶解时间2.5h、料液比1∶2 g/mL、酶用量2%。该条件下棕榈油提取率可达46.90%,所得油脂的酸价为6.01 mg/g KOH,可为水酶法制备棕榈油的工业化提供参考。     

正交试验优化杜仲叶中绿原酸酶法提取工艺研究

探索利用酶法提取杜仲叶中绿原酸的最佳工艺,通过酶种类的选择试验,确定纤维素酶是提取杜仲叶中绿原酸的一种有效酶制剂,并且通过单因素试验分析和正交试验优化,确定出最佳的绿原酸提取工艺。试验结果表明:酶法提取杜仲叶中绿原酸的最佳工艺参数为:提取pH为4.5、提取温度为40℃、加酶量为0.4%,提取时间为90min,得率可达52.24 mg/g。     

玉米胚芽分步酶解法提油工艺研究

研究低水分分步酶解提取玉米胚芽油工艺实验条件,确定最佳提取参数：料液比为1：0．78,玉米胚芽颗粒大小为105目,纤维素酶添加量为6,936 u/g,蛋白酶添加量为1,670 u/g,纤维素酶酶解时间为4.3小时,蛋白酶酶解时间为2．8小时,总提油率可达98.3%。     

酶解法提取葵花粕绿原酸工艺研究

为了优化葵花粕中绿原酸的提取工艺,采用纤维素酶、蛋白酶以及纤维素酶和蛋白酶联合作用于葵花粕提取绿原酸,探讨酶解时间、酶用量对绿原酸提取率的影响.结果表明,纤维素酶和蛋白酶联合作用能显著提高绿原酸的提取率,鉴于各影响因子之间的相互作用,在单因素试验的基础上,设计了正交试验,分析试验结果,得出最合适的工艺参数:酶解温度50℃,酶解时间1h,纤维素酶用量6ml,蛋白酶用量1.5ml,绿原酸提取率达到1.90%.     

玉米胚芽分步酶解法提油工艺的研究

研究了分步酶解法提取玉米胚芽油工艺的实验室条件,确定最佳提取参数为料液比1∶0.77,玉米胚芽颗粒大小为105目,纤维素酶添加量6870 U/g,蛋白酶添加量1648 U/g,纤维素酶酶解时间7.4 h,蛋白酶酶解时间2.8 h。在最佳条件下,清油提取率可达75.38%。     

酶法辅助聚二乙醇-200提取杜仲叶中绿原酸的工艺

采用Box-Behnken中心组合实验和响应面分析法,在单因素试验基础上,以酶用量、料液比、pH和酶解时间为影响因素,绿原酸提取率为响应值,对酶法辅助聚乙二醇(PEG)-200提取杜仲叶绿原酸的工艺进行优化。结果表明,其最佳工艺为:酶用量0.8%、料液比1︰20(g/mL),pH 4.4,酶解时间1.6 h。在此工艺条件下杜仲叶绿原酸提取率可达3.15%。该工艺条件温和、易于控制、提取效率高,可为杜仲叶中绿原酸的进一步开发研究提供工艺参考。     

葵花籽绿原酸酶法提取工艺研究

为了优化葵花籽中绿原酸的提取工艺。用纤维素酶和果胶酶分别和联合作用于葵花籽,探讨酶解的时间、酶解的温度以及各种酶的用量对提取葵花籽仁中绿原酸的影响。结果表明纤维素酶能够显著提高绿原酸的去除率,酶处理的最佳时间为1h,酶处理温度范围为40～50℃。通过正交实验,并用SAS统计分析软件分析实验结果,得出最合适的酶解参数,可以使绿原酸提取率达到1.36%,几乎能够完全提取葵花仁中的绿原酸。     

超声波辅助复合酶提取菊糖工艺优化

以菊芋块茎为原料,采用超声波辅助复合酶酶解法进行菊糖提取工艺研究。首先通过单因素试验和Plackett-Burman筛选试验确定菊糖提取工艺中影响显著的3 个因素--超声温度、超声时间和加酶量,再利用Box-Behnken试验及响应面分析法优化最佳提取工艺条件。结果表明：最佳提取工艺条件为料液比1∶20（g/mL）、超声温度51 ℃、加酶量120 μg/g（m（果胶酶）∶m（纤维素酶）=1∶4）、超声时间25 min、pH 5.5,优化后菊糖得率为72.2%。     

酶法提取茶树修剪叶中的蛋白及其性质研究

以蛋白的提取率为指标,利用Alcalace、果胶酶和纤维素酶在缓冲液条件下对茶树修剪叶中蛋白的提取进行了研究,发现这三种酶均能有效提高蛋白质的提取率,利用果胶酶和纤维素酶分别与Alcalace合用发现,纤维素酶和Alcalace合用能够很明显提高蛋白质的提取率,比单用Alcalace或纤维素酶分别提高了近35%和近50%。对利用Alcalace和纤维素酶协同作用得到的茶叶蛋白进行分析发现,利用碱法和酶法提取对于蛋白质的氨基酸组成基本没有影响,除吸水性和起泡稳定性略差于碱提茶叶蛋白外,酶法提取茶叶蛋白的其它指标如吸油性、乳化性、乳化稳定性以及起泡性均优于碱提茶叶蛋白。     

纤维素酶和果胶酶对番茄红素提取的影响

以番茄组织为材料,用含体积分数2%二氯甲烷的石油醚为提取溶剂,研究添加果胶酶和纤维素酶提取番茄红素的实验。结果表明,果胶酶和纤维素酶混合使用比单一酶的提取效率高,且果胶酶的提取效果比纤维素酶要好。在果胶酶和纤维素酶混合质量比为2:1时,提取番茄红素的最佳条件为A3B2C2D4,即混合酶用量0.6g/100g、酶解温度35℃、pH5.0、酶解时间5h,然后2%二氯甲烷的石油醚提取20min,4000r/min离心10min。因此,添加果胶酶和纤维素酶,用2%二氯甲烷的石油醚提取,可以提高番茄红素的提取率。     

高效液相色谱法测定青梅花、枝、叶中绿原酸类化合物

目的：建立反相高效液相色谱法同时测定青梅非果部位(花、枝、叶)中新绿原酸(NCA)、绿原酸(CA)及隐绿原酸(CCA)3 种绿原酸异构体的含量。方法：采用高效液相色谱法梯度洗脱,使用Luna C18 色谱柱,以体积分数2% 乙酸溶液和乙腈为流动相,二极管阵列检测器在波长328nm 处进行检测。结果：该方法线性范围宽,3种绿原酸异构体的线性范围均为5～200μg/mL,NCA、CA、CCA 的检出限分别为0.21、0.16、0.29μg/mL,定量限分别为0.76、0.50、0.98μg/mL,测得青梅花、枝、叶的30% 乙醇提取物中3 种绿原酸异构体的总含量分别为(48.26 ± 0.11)、(10.82 ± 0.04)、(21.33 ± 0.08)μg/g。结论：该方法简便、快速、准确,青梅花、枝、叶是优良的绿原酸类化合物天然资源。     

翻白草中7 种黄酮和有机酸的超声提取及含量测定

目的：建立高效液相色谱法分离测定翻白草中绿原酸、咖啡酸、金丝桃苷、槲皮素、柚皮素、山柰酚和芹菜素7 种成分的方法。方法：采用Phenomenex C18色谱柱（150 mm×4.6 mm,5 μm）分离7 种成分;流动相为甲醇和pH 3的乙酸溶液,梯度洗脱;流速1.0 mL/min,紫外检测波长350 nm,柱温40 ℃。结果：7 种成分在20 min内均达到基线分离,线性关系良好（r＞0.999 5）,平均回收率为84.61%～104.06%（相对标准偏差小于4.77%,n=3）。结论：翻白草中7 种活性成分的最佳提取条件为80%甲醇溶液、固液比1∶50（g/mL）、超声功率160 W、超声时间20 min。实际样品的测定结果表明,翻白草中7 种活性成分的含量为：绿原酸121.5 μg/g、咖啡酸60.5 μg/g、金丝桃苷127.2 μg/g、槲皮素108.6 μg/g、柚皮素294.0 μg/g、山柰酚61.1 μg/g和芹菜素114.0 μg/g。     

Enzymatic hydrolysis of carrot for extraction of a cloud-stable juice

The influence of various enzymes on the cell wall structure of carrots (Daucus carrota) was examined and related to changes in the juice extracted from the pulp with respect to volume, solids content, pH and viscosity. Crude preparations of cellulase (EC 3.2.1.4), hemicellulase, pectinase (EC 3.2.1.15), pectinesterase (EC 3.1.1.11) and an industrial grade pectinase/cellulase preparation (Rohament PC), all exhibiting cellulolytic as well as pectinolytic action, were used either singly or in combinations. Polarizing microscopy revealed a gradual loss of birefringence from the cell walls indicating degradation of ordered structure by all of the enzymes. The time for loss of birefringence was significantly correlated with the pectinase activity but not with the cellulase activity, suggesting that the presence of pectic substances is important in maintaining the ordered structure of the cell wall in carrot. Alterations to cell wall structure by pectinase were confirmed by scanning electon microscopy. Hydrolytic activity against carrots as measured by the increase in yield of juice could be predicted from the pectinase and cellulase activities through a linear regression equation (R = +0.72; P < 0.01) but the pectinolytic action was the most important factor. The yield of juice from the control carrot was 50.5% of the wet pulp mass with a total solids content of 7.9%, viscosity of 2.9 centistokes and a pH value of 5.65. Application of the enzyme preparations to the pulp (268–455 mg/kg) increased the volume of juice extracted, with the industrial grade preparation (440 mg/kg) yielding 50% more juice than the control for a 30-min incubation at 50 °C.     

Enzyme, bacterial inoculant, and formic acid effects on silage composition of orchardgrass and alfalfa

We evaluated the effects of cellulase (from Trichoderma longibrachiatum) application rates on neutral detergent fiber (NDF) concentration and fermentation products of orchardgrass (Dactylis glomerata L.) and alfalfa (Medicago sativa L.) silages harvested with decreasing dry matter (DM) digestibility. Additionally, the impacts of inoculant (Lactobacillus plantarum and Pediococcus cerevisiae), pectinase (from Aspergillus niger), or formic acid on silage composition were studied. Forages wilted to a DM content of about 320 g/kg were ensiled in laboratory silos for 60 d. Cellulase, combined with inoculant, was applied at 2, 10, and 20 ml/kg of herbage (at least 2500 IU/ml). Cellulase at 10 ml/kg was also applied alone or in combination with pectinase and inoculant or formic acid. The NDF concentration of orchardgrass silage decreased with increasing cellulase up to 20 ml/kg, at which NDF content was decreased by 30%. The NDF concentration of alfalfa silage decreased with increasing cellulase application up to 10 ml/kg, at which NDF content was decreased by 13%. Immature plants were more responsive to cellulase treatment than mature plants. Cellulase at 2 ml/kg combined with inoculant improved fermentation characteristics of the silages but generally, there was no effect on silage fermentation by higher cellulase applications, resulting in an accumulation of sugar. The improved fermentation of orchardgrass treated with cellulase and inoculant was mostly related to the effect of inoculant, whereas cellulase alone improved fermentation characteristics of alfalfa silage and this effect was enhanced by addition of inoculant. Decreased NDF and increased sugar concentrations did not improve the in vitro DM digestibility of cellulase-treated silages.     

几种澄清剂对荔枝提取液中多糖含量影响

在荔枝提取液澄清过程中,分别就果胶酶、纤维素酶、101澄清剂、壳聚糖、果胶酶和纤维素酶合用及果胶酶、纤维素酶和壳聚糖联合处理时对其中多糖的影响进行了研究,结果表明,这几种澄清方法对荔枝提取液中多糖都有不同程度的影响,在各处理的最佳澄清条件下,即果胶酶用量在6mL/L时,多糖损失率为12.2%;纤维素酶用量在10mL/L时,多糖损失率在7%;101澄清剂及助剂都采用9mL/L添加量时,多糖损失率为7.3%;壳聚糖用量为15mL/L时,多糖损失率为9.9%;果胶酶和纤维素酶用量分别是4mL/L、13mL/L,多糖损失率为10.6%;果胶酶和纤维素酶使用浓度分别是4mL/L、13mL/L,壳聚糖使用浓度是15mL/L时,多糖损失率为12.8%。     

反相高效液相色谱-光电二极管阵列检测器法测定杜仲叶发酵液中绿原酸的含量

建立反相高效液相色谱(HPLC)法测定杜仲叶发酵液中绿原酸的含量。色谱条柱SymmetrySheildRP18柱(3.9×300mm,5μm),以水:甲醇:乙酸(88:12:1.2,V/V)为流动相,流速1.0ml/min,检测波长326nm,柱温25℃。绿原酸对照品在2.24～11.2μg范围内线性关系良好(r=0.9993)。本方法简便、准确,线性范围宽,可用于含绿原酸的原料及产品的质量控制。     

Effect of substrate and fermentation conditions on pectinase and cellulase production by <Emphasis Type="Italic">Aspergillus niger</Emphasis> NCIM 548 in submerged (SmF) and solid state fermentation (SSF)

The present study deals with the optimization of substrate and fermentation conditions for the production of both pectinase and cellulase by Aspergillus niger NCIM 548 under same fermentation conditions in submerged fermentation (SmF) and solid state fementation (SSF) using a central composite face centered design of response surface methodology (RSM). As per statistical design, the optimum conditions for maximum production of pectinase (1.64 U/mL in SmF and 179.83 U/g in SSF) and cellulase (0.36 U/mL in SmF and 10.81 U/g in SSF) were, time 126 h, pH 4.6, and carbon source concentration 65 g/L in SmF and were time 156 h, pH 4.80, and moisture content 65% in SSF. The response surface modeling was applied effectively to optimize the production of both pectinase and cellulase by A. niger under same fermentation conditions to make the process cost-effective in both submerged and solid state fermentation using agro industrial wastes as substrate.