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1.
高活性α生育酚(dα生育酚)具有迄今所知的最大的维生素E活性。采用直接甲基化法进行了实验,得到高活性α生育酚产品。制备后的α生育酚含量为98.91%,浓度为0.34mg/mL。比旋光度为31.52°。甲基化反应前后维生素E的生理活性大多数得以保留。经用核磁共振碳谱作进一步确认,并与标准谱图进行比较。结果十分吻合,特别是三个手性碳的位移值均未发生变化,因此进一步确认甲基化过程中构型未受到破坏。  相似文献   

2.
低热量葡聚糖是水溶性食物纤维的一种。由于其中含有难消化成分,因而热量低。本文介绍了低热量葡聚糖制备的工艺条件,研究了该产品的一般性质,并测试了产品的粘度性质、比旋光度和颗粒形貌。  相似文献   

3.
目的建立一种硅胶柱层析纯化黑莓种籽油中天然VE的方法。方法采用单因素实验的方法,以维生素E的含量为考察指标,对洗脱剂种类、洗脱剂配比、硅胶用量、洗脱剂用量进行优化。结果黑莓天然VE的最优纯化工艺参数为:硅胶与维生素E粗提物的质量比3?1;乙醇?正己烷(8?1,V/V)为洗脱剂,洗脱剂用量为粗提物的15倍。在此条件下,纯化物中维生素E的含量可以达到(51.5±0.530)%。结论采用硅胶柱层析方法可以有效纯化黑莓天然维生素E。  相似文献   

4.
本试验以天然维生素E为基本原料,采用有机溶剂进行纯化浓缩,探讨了各试验因素对纯化结果的影响。正交结果显示:以15mL/g(VЕ原料)丙酮为纯化溶剂,结晶温度-16℃,结晶时间48h,浓缩效果最好。该条件下,维生素E含量由50%提高到62.97%;比旋光度由23.67°升至23.79°,维生素E活性成分几乎没有损失且有所提高。  相似文献   

5.
介绍了多环芳烃(PAHs)的性质、来源和危害,详述了油、污水、土壤中多环芳烃的脱除方法:物理法(包括萃取法、吸附法、层析法及人造纤维富集法等)、化学反应法、生物反应法、化学-生物降解法等,比较了各种脱除方法的优缺点。分析了维生素E油中的PAHs的来源。实验结果显示,硅胶柱层析法、微波萃取法、人造纤维bluerayon吸附等方法对维生素E油中PAHs的脱除有较好的效果。  相似文献   

6.
研究吸附脱色工艺条件(吸附剂种类、吸附剂用量、吸附脱色温度、吸附脱色时间)对米糠油吸附脱色综合效果(脱色率及谷维素、甾醇、维生素E等营养成分保留率和反式脂肪酸生成量)的影响。通过单因素试验和正交试验全概率分析得到最佳吸附脱色工艺条件:吸附脱色剂为活性白土,添加量为油重的3%,吸附脱色温度120℃,吸附脱色时间25 min。在此条件下得到脱色米糠油的色泽为Y20 R2.1(罗维朋比色槽25.4 mm),谷维素保留率为96.74%,甾醇保留率为90.60%,维生素E保留率为78.68%,反式脂肪酸未检出。脱色米糠油中营养成分得到了很好的保留。  相似文献   

7.
硅胶柱层析法纯化天然维生素E   总被引:2,自引:0,他引:2  
以粗孔硅胶做吸附剂,确定硅胶柱层析对天然维生素E浓缩液进行纯化的工艺条件。考察不同展开剂的层析效果,确定最优洗脱剂为环己烷:乙酸乙酯为80:20(V/V);以天然维生素E的含量和回收率为评价指标,考察了洗脱速度、上样量与层析柱再生条件对层析分离的影响。实验结果表明,硅胶柱纯化天然维生素E的最佳操作条件为流速0.5cm/min,上样量为90mg/mL柱体积,甲醇再生2倍床层体积。天然维生E含量可由原来的35%提高到85%以上,回收率达到80%以上。  相似文献   

8.
天然维生素E作为一种抗氧化剂,广泛应用在食品、保健品、化妆品、饲料产品等生产领域,此外,还作为医药产品,用于预防动脉硬化、心肌梗塞、脑溢血、糖尿病等疾病。天然维生素E主要存在于油料作物种子及植物油脂中,油脂脱臭馏出物是提取天然维生素E的主要原料。根据目前国内外科研和生产领域天然维生素E的发展现状,对以油脂脱臭馏出物为原料提取天然维生素E的主要提取工艺进行综述,分析了不同方法的优缺点,旨在为天然维生素E的提取研究提出新的发展方向。  相似文献   

9.
利用催化剂固体超强酸SO_4~(2-)/A-TiO_2合成维生素E亚油酸酯,研究了亚油酸酰氯与维生素E摩尔比、反应温度、SO_4~(2-)/A-TiO_2用量、反应时间对维生素E亚油酸酯产率的影响,以单因素试验为基础,利用响应面法优化了工艺条件。结果表明,SO_4~(2-)/A-TiO_2催化合成维生素E亚油酸酯最佳工艺条件为:亚油酸酰氯与维生素E摩尔比2.9∶1,反应温度45.6℃,SO_4~(2-)/A-TiO_2用量4.8%(以维生素E质量计),反应时间3.5 h。在最佳工艺条件下,维生素E亚油酸酯产率达到93.3%。维生素E亚油酸酯与维生素E相比具有更持久的抗氧化性能。  相似文献   

10.
开展了硅胶吸附脱除注射用大豆油氢过氧化物的研究。以过氧化值为评价指标,筛选硅胶种类,优化吸附工艺参数,并对吸附脱除氢过氧化物后的注射用大豆油的其他质量指标进行评价。结果表明,最佳吸附工艺条件为:选用粒度为70~200μm的进口硅胶,硅胶添加量11%,反应温度60℃,反应时间1. 0 h。在最佳工艺条件下,注射用大豆油的过氧化值、酸价、皂化值、碱性杂质、不皂化物等指标均符合注射用大豆油国家标准。  相似文献   

11.
硅胶和硝酸银硅胶柱层析分离生育酚与生育三烯酚   总被引:3,自引:1,他引:3  
本文以乙醚正己烷混合溶液为淋洗液,探讨了硅胶柱层析和硝酸银硅胶柱层析分离生育三烯酚和生育酚的效果。结果表明:通过改变淋洗液中乙醚含量可以将生育酚和生育三烯酚大部分分离;硝酸银硅胶柱层析分离生育三烯酚和生育酚的效果明显高于硅胶柱层析,其洗脱液中生育三烯酚可占VE总量的90%以上,最高达98.47%。  相似文献   

12.
Vitamin E from palm fatty acid distillate (PFAD) was concentrated in this study by removing the extraneous matters, especially free fatty acids (FFA) and acylglycerols. Original PFAD used in this study contained 85 and 13.7% of FFA and acylglycerols, respectively. Acylglycerols in PFAD were first hydrolyzed using commercially available immobilized Candida antarctica lipase at 60C for 6 h. The fatty acids liberated, together with the existing FFA were then removed by neutralization. Hydrolysis followed by neutralization step concentrated vitamin E from an initial amount of 0.37 to 4.32%. Hydrolysis was an important step as without hydrolysis, neutralization could only concentrate vitamin E to 1.80%. Oil extracted from hydrolyzed and neutralized PFAD was then subjected to a normal-phase silica adsorption chromatography. The column was first eluted with hexane followed by isopropanol. A large amount of acylglycerols was removed during the first elution, while vitamin E was desorbed by isopropanol, with a recovery of >90%. Vitamin E concentration after hydrolysis, neutralization and adsorption chromatography was 15.2%. The method described in this study offers an alternative for the existing separation methods. It could be applied as one of a series of steps in producing high-purity vitamin E concentrates.  相似文献   

13.
Colloidal stabilisation of all malt and adjunct lager beers through selective removal of haze sensitive glycoproteins using silica gel and tannoid polyphenols using polyvinylpolypyrrolidone (PVPP) or a polyvinylpyrrolidone (PVP)‐modified silica gel has been demonstrated during full brewery production. At this scale PVPP and the PVP‐modified silica gel exhibited equivalent binding capability for tannoid polyphenols although PVPP removed additional polyphenolic species. Characterisation of proanthocyanidins following treatment at 4°C with PVPP and the PVP‐modified silica gel silica co‐product confirmed that PVPP removes a wider range of polyphenolics. Both products exhibited poorer polyphenolic binding capability at 4°C as would be expected for a physical adsorption process.  相似文献   

14.
Five adsorbents were studied for their ability to remove terpenes from cold-pressed Valencia orange oil by frontal-analysis displacement adsorption chromatography. Only the potable solvent 95% aqueous ethanol was used in the process; columns were dry-packed to eliminate the use of hexane. The most successful studies were carried out using silica gel and Florisil. Adsorptive capacities of 4.4 and 2.0g oil/g adsorbent were achieved for silica gel and Florisil, respectively. Compositions of the oil fractions were determined by gas chromatography and peaks identified by mass spectrometry. Silica gel provided products with the lowest terpene level and the highest oxygenated compound content. The terpene content of the product considered best was reduced to one fifth and one seventh of the original level for Florisil and silica gel, respectively, and had higher oxygenated compound levels than either 10-fold or 25-fold orange oil concentrates.  相似文献   

15.
玉米胚预榨毛油和浸出毛油品质及综合脱色效果的研究   总被引:1,自引:0,他引:1  
研究了玉米胚预榨浸出生产中所得预榨毛油和浸出毛油的品质及其脱色效果和脱色过程中营养成分的保留率。结果显示,预榨毛油比浸出毛油的色泽浅、维生素E含量高、酸价也较低;添加相同量的活性白土分别对两种毛油进行吸附脱色,预榨毛油较浸出毛油脱色率平均高出约4.6%;白土用量4%时,脱色预榨毛油的色泽基本达到玉米油国标中二级油的指标,而浸出毛油即使在白土用量6%时其色泽也很难达到二级油指标;经吸附脱色,预榨毛油中植物甾醇和维生素E保留率普遍高于浸出毛油,在白土用量5%时,预榨毛油较浸出毛油甾醇保留率高出14%,不同白土用量,预榨毛油比浸出毛油甾醇保留率平均高出约10%;白土用量2%时,预榨毛油较浸出毛油维生素E保留率提高约5.6%;两种玉米毛油所含维生素E中4种生育酚及4种生育三烯酚都存在,组分齐全;吸附脱色过程中γ-生育酚和β-、γ-生育三烯酚的损失较明显,其他组分含量的损失较少。因此,合理的玉米油精炼应将预榨毛油和浸出毛油分别进行适度精炼,以提高吸附脱色效果和营养成分保留率。  相似文献   

16.
儿茶素单体分离制备方法   总被引:1,自引:0,他引:1  
茶叶中含有丰富的儿茶素类物质,占茶叶干重12%~24%,是茶叶中最具生理活性和保健功效的物质。文中对目前国内外纯化制备儿茶素的常见方法进行了综述。常见的儿茶素制备方法包括纤维素柱层析、葡聚糖凝胶(Sephadex LH—20)、硅胶柱层析、吸附树脂柱层析和高速逆流色谱等方法。通过这些方法制备的儿茶素单体纯度不高,仍需结合结晶、制备型液相色谱技术或膜分离技术进行进一步纯化,从而才能获得高纯度的儿茶素单体。在儿茶素单体的制备方法中,每种方法都有相应的优缺点。Sephadex LH—20柱层析分离的量较大,但是分离时间较长,而且Sephadex LH—20柱填料昂贵;高速逆流色谱分离效果较好,得到的儿茶素单体的纯度较高,分离时间相对要短,但是目前市场上只有分析型,分离的量相对少;硅胶材料廉价,但是分离的效果不佳,且分离过程相对繁琐,单体制备量较小;吸附树脂柱层析分离已实现EGCG单体的工业化生产,但在其他儿茶素单体的分离制备上尚不成熟。  相似文献   

17.
A simple imprinted amino-functionalized silica gel material was synthesized by combining a surface molecular imprinting technique with a sol–gel process for solid-phase extraction–high performance liquid chromatography (SPE–HPLC) determination of diethylstilbestrol (DES). Activated silica gel was used as the supporter and non-imprinted silica sorbent was synthesized without the addition of DES using the same procedure as that of DES-imprinted silica sorbent. Compared with non-imprinted polymer particles, the prepared DES-imprinted silica sorbent showed high adsorption capacity, significant selectivity, good site accessibility and fast binding kinetics for DES. The maximum static adsorption capacity of the DES-imprinted and non-imprinted silica sorbent for DES was 62.58 mg g−1 and 19.89 mg g−1, respectively. The relatively selective factor value of this DES-imprinted silica sorbent was 61.7 at the level of 50 mg L−1. And the uptake kinetics was fairly rapid so that the adsorbent equilibrium was achieved within 10 min. Furthermore, the DES-imprinted polymers were used as the sorbent in solid-phase extraction to determine DES in fish samples. The MIP–SPE–HPLC method showed higher selectivity and good recoveries higher than 87.5% (R.S.D. 11.6%).  相似文献   

18.
宋二立 《中国油脂》2021,46(4):7-10
利用PLA1脱除大豆毛油中的磷脂,再用硅胶吸附脱除大豆油中的残磷和残皂。以酶法脱胶后含磷量、硅胶吸附脱皂后的含磷量和含皂量为评价指标,研究酶法脱胶及硅胶吸附脱皂对大豆油脱胶脱皂效果的影响。结果表明:在大豆油pH 5.5~6、去离子水添加量3%、反应时间6~8 h的脱胶条件下,酶法脱胶效果随PLA1添加量的增加而提高,PLA1添加量分别为50、75、100 mg/kg时,脱胶大豆油中含磷量分别从566.36、538.02、562.76 mg/kg降至44.67、18.99、17.01 mg/kg,再添加油质量0.1%的SORBSIL R92硅胶,大豆油含磷量分别降至41.21、16.35、15.42 mg/kg,含皂量分别从37、23、14 mg/kg降至14、8、5 mg/kg。酶法脱胶后大豆油酸值和过氧化值有所升高,3个油样的酸值(KOH)平均升高0.63 mg/g,过氧化值平均升高0.007 g/100 g。硅胶吸附脱皂也造成大豆油酸值和过氧化值有所升高。  相似文献   

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