响应面优化葡萄籽中原花青素的双水相萃取条件

采用聚乙二醇-硫酸铵双水相体系分离纯化葡萄籽中原花青素,确定其双水相体系组成为20%PEG4000-10%(NH4)2SO4,并通过单因素实验和响应面分析实验探讨粗提液质量分数、pH和NaCl质量分数对萃取效果的影响。最佳萃取条件为:粗提液质量分数17.2%、pH4.8、NaCl质量分数0.7%。在此条件下,葡萄籽原花青素主要分布在上相,原花青素的萃取率可达96.66%。     

壳聚糖絮凝—盐诱导双水相萃取分离红葡萄籽中原花青素

以原花青素回收率为主要考察指标,通过正交试验确定壳聚糖絮凝纯化的最佳条件;通过研究盐诱导(盐的种类和浓度)双水相体系对红葡萄籽中原花青素萃取效果,建立盐诱导双水相萃取最佳条件。结果表明:在20mL原花青素提取液中,壳聚糖的加入量2 mL、絮凝温度35℃、提取液pH 4时,葡萄籽原花青素回收率为95.62%;盐诱导双水相萃取分离絮凝后原花青素提取液结果表明,加入K_2HPO_4诱导双水相萃取原花青素效果较好,在2 mL絮凝后原花青素提取液中,K_2HPO_4加入量为0.5g时,原花青素萃取率和分配系数分别为87.2%和1.97。     

乙醇/硫酸铵双水相体系分离纯化葡萄籽总黄酮

利用乙醇-硫酸铵双水相体系分离纯化葡萄籽中总黄酮,首先对无水乙醇、(NH4)2SO4、黄酮粗提取液质量分数、pH值、NaCl质量分数进行单因素研究,确定双水相体系组成为23%无水乙醇-17%(NH4)2SO4。然后利用Box-Benhnken Design实验,对黄酮粗提取液质量分数、pH值、NaCl质量分数进行了优化,结果表明:黄酮粗提取液质量分数21.3%、pH 7.2、NaCl质量分数1.97%,此条件下葡萄籽总黄酮的萃取率可达到98.8%;与预测值96.437 2%接近。     

响应面法优化黑胡萝卜红色素双水相萃取工艺

采用聚乙二醇（PEG）/硫酸铵双水相体系萃取纯化黑胡萝中的花青素。通过单因素实验考察了硫酸铵、PEG6000、粗提液的质量分数对花青素选择性系数和萃取率的影响,并以花青素的萃取率为响应值,结合响应面试验优化萃取工艺。结果表明,各因素对萃取率的影响程度由大到小依次为硫酸铵质量分数>粗提液质量分数>PEG6000质量分数。以双水相体系的总质量为基准,实验最佳萃取条件为:硫酸铵质量分数为20.0%、粗提液质量分数为12.0%、PEG6000质量分数为14.0%,黑胡萝卜红色素的平均萃取率为94.17%。此萃取方法得到的黑胡萝卜红色素具有一定的抗氧化活性,对DPPH自由基清除能力的IC₅₀值为30.51 mg/L。     

葡萄籽中原花青素提取工艺

以发酵后葡萄籽为原料,研究微波、纤维素酶和超声波辅助提取葡萄籽中原花青素的工艺条件,对影响原花青素提取率的因素进行考察,通过正交试验确定葡萄籽中原花青素的最佳提取工艺。结果表明最佳方法为微波辅助提取,其最佳工艺条件：料液比1:25(g/mL)、乙醇体积分数80%、微波时间40s、微波功率115W,原花青素的提取率为10.70%。     

TritonX-100-硫酸铵双水相体系分离地榆根总黄酮

目的:研究利用双水相体系萃取地榆根总黄酮提取的最佳工艺条件。方法:探讨了Triton X-100质量分数,硫酸铵质量分数,黄酮粗提液质量分数、Na Cl质量分数和p H等因素对总黄酮萃取率的影响,并采用Box-Benhnken实验确定了最佳实验条件。结果:双水相萃取黄酮最佳条件为,确定双水相体系组成15%Triton X-100/15%硫酸铵,黄酮粗提液质量分数12%、Na Cl质量分数0.5%、p H6,地榆根总黄酮前萃取率达到80.02%;反萃取的最佳条件:取1.5m L黄酮萃取上相和2m L乙酸丁酯混合,反萃取率为80.03%。结论:采用双水相萃取地榆根总黄酮简单、易行,生产成本低,在中药提取中具有良好应用前景。     

赤霞珠葡萄梗黄酮、原花青素和多酚的提取工艺优化

研究赤霞珠葡萄梗中黄酮、原花青素和多酚的提取工艺。以葡萄梗中黄酮、原花青素和多酚含量的综合评分为评价指标,采用正交设计优化赤霞珠葡萄梗黄酮、原花青素和多酚超声辅助双水相提取的条件。结果表明:超声辅助双水相提取的最优工艺条件为:料液比为1:40(g/mL)、超声时间为50 min、乙醇质量分数为24%、硫酸铵质量分数为20%。在此提取条件下,放大8倍赤霞珠葡萄梗中黄酮、多酚和原花青素的含量分别为72.85、122.21、87.67 mg/g,相对标准偏差在3%以内,说明该工艺具有可行性。     

均匀设计优化超临界CO2提取含原花青素的葡萄籽油

以原花青素的提取率和葡萄籽的出油率为考察指标,利用均匀设计法对超临界CO2萃取时间、萃取压力、萃取温度进行了优化,得到最佳工艺条件为:萃取压力15 MPa,萃取时间3 h,萃取温度50 ℃;在最佳条件下葡萄籽出油率为(10.92±0.25)%,原花青素提取率为(23.4±7.2)mg/100 g.在加入无水乙醇夹带剂的前提下,利用超临界CO2萃取葡萄籽油,可以使油中含有原花青素,提高葡萄籽油的品质.     

双水相法提取油菜籽粕中原花青素

采用双水相法对油菜籽粕中原花青素进行提取。在单因素实验基础上,选取乙醇体积分数、硫酸铵质量分数、p H和提取温度为自变量,以原花青素得率为响应值,利用Box-Benhnken中心组合设计原理和响应面分析法,研究各自变量的交互作用对原花青素得率的影响,建立油菜籽粕原花青素提取得率的二次回归方程。结果表明,双水相法提取油菜籽粕原花青素的最佳工艺条件:乙醇体积分数26%,硫酸铵质量分数18%,p H2.40,提取温度39℃,在此最优条件下原花青素得率为7.78 mg/g。该研究为油菜籽粕中原花青素合理开发利用提供一定的数据基础。     

超声微波双辅助提取葡萄籽低聚原花青素的研究

以新疆吐鲁番的赤霞珠葡萄籽为研究对象,利用超声微波双辅助法提取其中的低聚原花青素.以低聚原花青素提取率为考察指标,研究固液比、微波功率、微波辐照时间、作用次数、乙醇体积分数5个单因素对葡萄籽低聚原花青素提取率的影响.并采用响应面分析法对提取结果进行优化.结果表明,采用超声微波双辅助萃取技术得到的低聚原花青素提取率较单独采用超声或微波辅助得到的原花青素提取率高.在以70.3％vol的乙醇为提取溶剂、固液比为1∶14.6 (g∶mL)、超声处理30min、微波功率400W、微波时间30s的条件下,得到的低聚原花青素提取率最大为7.62mg/g.     

采用微波辅助法提取葡萄籽中的原花青素

以葡萄籽为原料 ,研究了微波对葡萄籽原花青素的浸出和结构的影响。结果表明 ,以乙醇为介质 ,微波处理有利于葡萄籽中原花青素的浸出 ,葡萄籽整粒用料液比 (g∶mL) 1∶11的体积分数 70 %乙醇溶液 ,微波处理10s,在 5 0℃水浴浸提 30min ,原花青素浸提量为 4 10 9mg/g ,较不用微波处理同等水浴条件浸提量增加 1 715mg/g。通过对微波联合水浴浸提和单纯水浴浸提的原花青素的紫外图谱显示 ,短时微波处理对原花青素的分子结构没有破坏作用。     

Optimization of Ultrasonic‐Assisted Aqueous Two‐Phase Extraction of Phloridzin from Malus Micromalus Makino with Ethanol/Ammonia Sulfate System

Application of an aqueous two‐phase system (ATPS) coupled with ultrasonic technology for the extraction of phloridzin from Malus micromalus Makino was evaluated and optimized by response surface methodology (RSM). The ethanol/ammonium sulfate ATPS was selected for detailed investigation, including the phase diagram, effect of phase composition and extract conditions on the partition of phloridzin, and the recycling of ammonium sulfate. In addition, the evaluation of extraction efficiency and the identification of phloridzin were investigated. The optimal partition coefficient (6.55) and recovery (92.86%) of phloridzin were obtained in a system composed of 35% ethanol (w/w) and 16% (NH₄)₂SO₄ (w/w), 51:1 liquid‐to‐solid ratio, and extraction temperature of 36 °C. Comparing with the traditional solvent extraction with respective 35% and 80% ethanol, ultrasonic‐assisted aqueous two‐phase extraction (UAATPE) strategy had significant advantages with lower ethanol consumption, less impurity of sugar and protein, and higher extracting efficiency of phloridzin. Our result indicated that UAATPE was a valuable method for the extraction and preliminary purification of phloridzin from the fruit of Malus micromalus Makino, which has great potential in the deep processing of Malus micromalus Makino industry to increase these fruits’ additional value and drive the local economic development.     

混合溶剂一步法提取葡萄籽油和原花青素的工艺研究

研究了混合溶剂一步法提取葡萄籽油和原花青素的工艺,试验结果显示最优工艺为料液比1：7、混合溶剂正己烷／95％乙醇比例4：6,提取温度65℃、提取时间3．5h,在此条件下葡萄籽油提取率为92．62％±3．74％,原花青素提取率为56．18％±4．12％。     

Influence of solvent and temperature on extraction of phenolic compounds from grape seed,antioxidant activity and colour of extract

This study was aimed to investigate the influence of solvent (water and ethanol in concentration: 50%, 70% and 96%) and extraction temperature (25–80) °C on polyphenols extraction of grape seed (Vitis vinifera L. cv. “Frankovka”) cultivated in Eastern Croatia. The best results were reached using 50% ethanol at 80 °C. The most abundant individual polyphenolic compound was catechin which makes the average of 45.11% of the total phenolic content followed by epicatechin (34.45%), procyanidin B₂ (12.90%), gallic acid (5.34%), gallocatechin (1.58%), epicatechin gallate (1.01%). The antioxidant activity of extracts was determined by DPPH‐method and it was highly dependent on extraction solvent and temperature. The total extractable proanthocyanidins content of extract had the highest positive correlation (r = 0.994) with antioxidant activity, which indicated that these compounds might be the most important antioxidant in examined grape seed extracts. Relationship between phenolic content and colour of extracts was observed.     

Partition Behaviors of Different Polar Anthocyanins in Aqueous Two-Phase Systems and Extraction of Anthocyanins from <Emphasis Type="Italic">Nitraria tangutorun</Emphasis> Bobr. and <Emphasis Type="Italic">Lycium ruthenicum</Emphasis> Murr.

This study aimed to investigate the partition behaviors of various polar anthocyanins in NaH₂PO₄/(NH₄)₂SO₄-ethanol aqueous two-phase systems (ATPS) and to extract anthocyanins from Nitraria tangutorun Bobr. and Lycium ruthenicum Murr. Anthocyanins in Hibiscus sabdariffa L., Morus atropurpurea Roxb., N. tangutorun, and L. ruthenicum were profiled using HPLC-ESI-MS/MS and HPLC-DAD, and the partition behaviors of total anthocyanins and main anthocyanins were studied. The partition coefficient of anthocyanins increased with increased hydrophobicity, and low-polarity anthocyanins exhibited a higher preference for the top phase in NaH₂PO₄/(NH₄)₂SO₄-ethanol ATPS. Additionally, the NaH₂PO₄-ethanol ATPS gave higher selectivity and total anthocyanin yield than the (NH₄)₂SO₄-ethanol system. Extraction at 65 °C for 45 min and at 45.5 °C for 45 min using 28% NaH₂PO₄ and 26% ethanol (w/w) led to the recovery of 98.91 ± 0.03% of N. tangutorun anthocyanins (3.62 ± 0.05 mg/g) and 99.84 ± 0.01% of L. ruthenicum anthocyanins (13.16 ± 0.29 mg/g) from raw material; more than 70% of total sugars were removed in a single step. NaH₂PO₄-ethanol aqueous two-phase extraction is a promising method for extracting anthocyanins from N. tangutorun and L. ruthenicum.     

利用微波技术提取葡萄籽粕中原花青素的研究

通过试验室专用微波装置对葡萄籽粕中原花青素提取工艺进行了研究,探讨了溶剂种类、提取浓度、提取时间、提取料液比、提取温度对提取率的影响,并对以上因素通过响应面分析,探索最佳提取工艺。结果表明:以70%乙醇为提取剂,料液比为1∶7.5,并加0.5%柠檬酸辅助提取,微波提取温度约55℃,2次提取总时间90min,原花青素含量为7.06%,提取率(69.54±3.46)%,优于传统水浴加热提取方式。     

Aqueous Two-Phase Micellar System for Nisin Extraction in the Presence of Electrolytes

Liquid–liquid extraction for aqueous two-phase micellar systems (ATPMS) is a promising technique that can either replace or be used as a complementary process to more typical chromatographic operations in order to reduce the costs of downstream processing of many biological products. This method offers attractive conditions when exploited in the extraction/purification of a target protein directly on the culture medium. Nisin, an extracellular antimicrobial peptide, is produced by Lactococcus lactis and is effective at controlling a wide range of Gram-positive bacteria, including multidrug-resistant pathogens. This study evaluates ATPMS composed by a nonionic surfactant, Triton X-114, in the presence or absence of electrolytes, to improve the extraction of nisin. The partitioning behavior of nisin showed that it can be directly extracted from the fermentation media. The partitioning coefficient (K _nis) of the commercial nisin in the presence of electrolytes showed K _nis values of 5.6 and 5.4 for MgSO₄ and (NH₄)₂SO₄, respectively. Similar behavior was observed for the produced nisin where K _nis values were 4.1 and 5.1 for MgSO₄ and (NH₄)₂SO₄. After partition, the commercial nisin activity in the micelle-rich phase, in the absence of electrolytes, was 3.3 logAU/mL, and in the presence of MgSO₄ and (NH₄)₂SO₄, the activity was 5.0 logAU/mL. The produced nisin activity with and without MgSO₄ was around 3.5 logAU/mL; however, in the presence of (NH₄)₂SO₄, nisin activity was 4.5 logAU/mL. The increase in nisin activity after partitioning with salts encourages further researches for the optimization of nisin extraction.     

Preliminary study of L‐lysine production by Bacillus species using various agricultural by‐products

The production of lysine by Bacillus megaterium SP‐14 and Bacillus circulans Tx‐22 using agricultural by‐products as carbon and nitrogen sources was assessed. Among the carbon substrates used were potato, sorghum, plantain, millet, yam, cassava, and corn starches, while the nitrogen sources include cowpea, bambara‐nut, cotton seed, groundnut, soybean, and blood meals. The effect of natural nitrogen sources (1.0% w/v) and synthetic nitrogen source (4.0% w/v (NH₄)₂SO₄) on lysine production by the Bacillus strains showed that natural nitrogen sources gave better lysine yields.     

发芽糙米多糖双水相萃取工艺优化及其抗氧化活性

以发芽糙米为原料,采用超声波辅助双水相法萃取对发芽糙米多糖的分配系数进行研究,多糖得率作为考察目标,通过正交试验确定超声波辅助双水相萃取发芽糙米多糖的最佳提取工艺条件。结果表明:发芽糙米多糖最优提取工艺为选用PEG6000、PEG6000添加量15.7%、硫酸铵添加量14.8%、萃取时间40min,该条件下多糖得率为81.07%。并采用DPPH法、邻苯三酚自氧化法和邻二氮菲法检测提取的多糖抗氧化活性。研究发现发芽糙米多糖对DPPH自由基、超氧阴离子自由基以及羟基自由基均有较强的抗氧化作用。