离子交换树脂法提纯维生素C磷酰化反应液

采用D301大孔弱碱阴离子交换树脂分离提纯维生素C磷酰化反应液.测定了室温下D301树脂吸附维生素C磷酸酯钠的动力学曲线和吸附等温线,考察了溶液pH值、温度、盐酸洗脱液浓度等因素对吸附的影响.最后用D301树脂对磷酰化反应液进行梯度洗脱,并用HPLC进行分析.结果表明D301树脂吸附维生素C磷酸酯钠约60 min达到平衡,Freundlich方程可以较好地描述树脂对维生素C磷酸酯钠的吸附.在室温下将磷酰化反应液调节pH至1～2后上柱吸附,依次用0.05 mol/L、0.2 mol/L、2.0 mol/L的盐酸溶液洗脱,收集0.2 mol/L盐酸洗脱液,用HPLC分析,结果其维生素C磷酸酯含量大于97%.     

维生素D在炎症性肠病中的作用

维生素D是一种影响肠道内稳态的免疫调节因子。最近有证据支持这种微量营养素在炎症性肠病(IBD)发展中的重要作用。本综述旨在概述维生素D可能的生物学作用机制(在免疫系统中的作用)及其对IBD的治疗意义。根据体外和动物研究表明，维生素D可改善上皮屏障的完整性，调节炎症反应，并影响免疫反应。最近的研究还表明，维生素D缺乏在IBD患者中非常普遍。越来越多的证据表明维生素D在IBD的病理生理学中起一定作用，维生素D通过调节先天免疫和适应性免疫在IBD中起到保护作用。因此，探讨维生素D作为治疗剂的在IBD中的潜在作用极为重要。     

青霉素和柠檬酸废菌丝体的综合利用

1产品介绍1.1麦角固醇和维生素D2麦角固醇以一种重要的医药化工原料,可用于“考的松”和“激素黄体酮”等药物和农药的生产。同时麦角固醇又是维生素D2生产的主要原料。维生素D2可提高人体和动物的钙磷吸收,促进骨骼的形成。若摄入量不足,会引起严重的缺乏病,如儿童的佝偻病,老年人的骨质疏松病等。我国人口众多,儿童佝偻病发病率很高,尤其在北方,高达50%。我国老年骨质疏松病患者达6000多万,以人口比例计算,高于发达国家2倍以上。许多发达国家,如美国和日本自20世纪70年代推出了许多维生素D强化食品,如VD奶、VD软饮料等。美国RDA(Reco…     

光化学合成维生素D

本文报道了维生素D的发现以及它们的光化学合成与进展。中国科学院理化技术研究所开发了一条从胆固醇合成 7 DHC的新路线,提出了一条光化学合成维生素D3 的创新技术路线,并已经转让实施。同时还提出一条光化学合成维生素D2 的创新技术路线。     

杭州投产全球最大维生素D3项目

11月11日，位于杭州下沙经济技术开发区的杭州下沙生物科技有限公司正式开工，标志着一个总投资2亿元、年产500吨维生素D3油剂和2000吨维生素D3饲料添加剂的全球最大维生素D3项目正式投产。     

食品中维生素D3测试的探讨

当维生素D3被人体完全吸收以后,前维生素D3能够转化成维生素D3照样被人体吸收,而且它们之间可以相互转换,从而被人体吸收,现在的奶粉等很多的国家标准中,没有把前维生素D3的含量计算在内。     

气相色谱法测定维生素D2中残留有机溶剂

建立了维生素D2中残留有机溶剂的气相色谱测定方法。使用DB-wax毛细管柱,FID检测器,能快速测定(20min)甲醇、乙醇、乙酸乙酯等有机溶剂残留量。乙醇检测限为0．3μg／mL(信噪比为2),精密度试验的RSD均小于3％(n=6),重现性试验的RSD均小于2％(n=5),回收率为99．86％100．6％。该方法可以作为维生素D2产品中有机溶剂残留量的限度检测方法。     

高单位维生素D3油脱色技术的研究

研究用粉状活性炭对颜色较深的维生素D3油进行脱色处理,以达到国际交易市场之标准。针对维生素D3油颜色较深之因素进行分析,借鉴油脂脱色处理方法,选择脱色吸附剂,比较脱色剂用量、脱色溶剂、脱色温度、脱色时间等因素的影响,确定用粉状活性炭对维生素D3油进行二次脱色,即用环己烷为脱色溶剂,第一次用5%活性炭（w/w维生素D3油）,第二次用3%活性炭（w/w维生素D3油）,脱色温度50℃,恒温回流脱色时间1小时。使脱色后的维生素D3油品质达到国际先进水平。     

麦角固醇光解生产维生素D2新工艺

本工艺采用紫外光照法用麦角固醇生产维生素D2(简称VD2)，并对其生产的条件进行了优化和比较，进行了工业化实验，得到了较好的结果。最终麦角固醇转化率为50％以上，维生素D2选择性得率为40％以上．达到了工业化的要求。     

合成丁醛乙二醇缩醛的催化剂研究进展

综述了氯化铁、硫酸铁、硫酸铁铵、SnO、硫酸铜、磺化聚氯乙烯、聚氯乙烯 三氯化铁、D61和D72离子交换树脂、维生素C、固体超强酸TiO2/SO42-、固体超强酸SO42-/TiO2 MoO3、钨硅酸、固载杂多酸盐TiSiW12O40/TiO2以及HY分子筛等14种催化剂催化合成丁醛乙二醇缩醛的实验结果。结果表明:磺化聚氯乙烯、聚氯乙烯 三氯化铁、D61和D72离子交换树脂和TiSiW12O40/TiO2等4种催化剂对合成丁醛乙二醇缩醛的收率较高,具有实际应用价值。     

SeO2对维生素D衍生物烯丙位氧化的概述

维生素D 及其衍生物不仅可以作为治疗疾病的药物,而且也可以成为化学合成的原料.大多数维生素D 衍生物的合成都需要经过烯丙位的氧化,然而维生素D 衍生物烯丙位氧化产率很低,这对维生素D 衍生物的开发和研究带来了困难.因此对近年来以二氧化硒为氧化剂对维生素D 衍生物进行烯丙位氧化—环氧法和Riley 氧化法进行了总结,并对此近年来研究成果进行了分析总结.     

Influence of Vitamin D on the Vasoactive Effect of Estradiol in a Rat Model of Polycystic Ovary Syndrome

We examined the vasoactive effect of estradiol in a rat model of early PCOS and the influence of vitamin D deficiency (VDD). We created a model of chronic hyperandrogenism and VDD in adolescent female Wistar rats (N = 46) with four experimental groups: vitamin D supplemented (T-D+), VDD (T-D-), hyperandrogenic and vitamin D supplemented (T+D+), and hyperandrogenic and VDD (T+D-). T+ groups received an 8-week-long transdermal Androgel treatment, D-animals were on vitamin D-reduced diet and D+ rats were supplemented orally with vitamin D3. Estrogen-induced vasorelaxation of thoracic aorta segments were measured with a wire myograph system with or without the inhibition of endothelial nitric oxide synthase (eNOS) or cyclooxygenase-2 (COX-2). The distribution of estrogen receptor (ER), eNOS and COX-2 in the aortic wall was assessed by immunohistochemistry. VDD aortas showed significantly lower estradiol-induced relaxation independently of androgenic status that was further decreased by COX-2 inhibition. COX-2 inhibition failed to alter vessel function in D+ rats. Inhibition of eNOS abolished the estradiol-induced relaxation in all groups. Changes in vascular function in VDD were accompanied by significantly decreased ER and eNOS staining. Short-term chronic hyperandrogenism failed to, but VDD induced vascular dysfunction, compromised estrogen-dependent vasodilatation and changes in ER and eNOS immunostaining.     

高效液相色谱法测定化妆品中VD2及VD3

采用高效液相色谱法对VD2及VD3进行测定,以甲醇/乙腈(90∶10)为流动相,流速为1.0 mL/min,DAD检测器,C18柱,检测波长260 nm,得到在0.50～50.0 mg/L浓度范围内有较好的线性关系,相关系数分别为rVD2=0.999 4和rVD3=0.999 5,回收率为96.9%～100.6%,方法检出限VD2为0.13 mg/L,VD3为0.06 mg/L。该方法快速方便,可用于化妆品VD2及VD3的检测。     

维生素D衍生物的临床应用及合成方法

维生素D及其衍生物不仅可以作为治疗疾病的药物,而且也可以成为化学合成的原料。现在有些维生素D及其衍生物已经作为商品投放在市场上,并对临床研究和工业合成做出了巨大的贡献。对目前临床做出贡献的维生素D衍生物马沙骨化醇、度骨化醇、帕立骨化醇、骨化三醇、卡泊三醇和他卡西醇在临床方面的应用及合成路线进行了介绍,对药物的开发提供参考,并进一步提出未来药物开发的前景。     

The determination of vitamin d in margarine by high performance liquid chromatography

Margarine manufactured in South Africa contains vitamin D added at a level of 1-3 international units per gram. Because of the high ratio of lipid to vitamin D, it is difficult to determine the vitamin content for control purposes. A high performance liquid Chro-matographic method for the determination of vitamin D in mar-garine is proposed. The unsaponifiable fraction of a margarine sample is chromatographed twice on an adsorption system. The vitamin D fraction collected from this column is finally injected onto a reverse phase system where vitamins D₂ and D₃ are separated and quantitated with an ultraviolet detector. Vitamin D₂ is used as an internal standard for vitamin D₃ or vice-versa, depending on the form of the vitamin added to margarine. The recovery of 100 ng/g vitamin D₃ added to a margarine mix was 100.1% (coefficient of variation 13.2% for 12 replicates) as calculated from the ratio of peak areas. The detection limit is 1 ng vitamin D. Results for 3 samples of margarine and one sample of butter are given.     

Vitamin D Deficiency Induces Chronic Pain and Microglial Phenotypic Changes in Mice

The bioactive form of vitamin D, 1,25-dihydroxyvitamin D (1,25D3), exerts immunomodulatory actions resulting in neuroprotective effects potentially useful against neurodegenerative and autoimmune diseases. In fact, vitamin D deficiency status has been correlated with painful manifestations associated with different pathological conditions. In this study, we have investigated the effects of vitamin D deficiency on microglia cells, as they represent the main immune cells responsible for early defense at central nervous system (CNS), including chronic pain states. For this purpose, we have employed a model of low vitamin D intake during gestation to evaluate possible changes in primary microglia cells obtained from postnatal day(P)2-3 pups. Afterwards, pain measurement and microglia morphological analysis in the spinal cord level and in brain regions involved in the integration of pain perception were performed in the parents subjected to vitamin D restriction. In cultured microglia, we detected a reactive—activated and proliferative—phenotype associated with intracellular reactive oxygen species (ROS) generation. Oxidative stress was closely correlated with the extent of DNA damage and increased β-galactosidase (B-gal) activity. Interestingly, the incubation with 25D3 or 1,25D3 or palmitoylethanolamide, an endogenous ligand of peroxisome proliferator-activated-receptor-alpha (PPAR-α), reduced most of these effects. Morphological analysis of ex-vivo microglia obtained from vitamin-D-deficient adult mice revealed an increased number of activated microglia in the spinal cord, while in the brain microglia appeared in a dystrophic phenotype. Remarkably, activated (spinal) or dystrophic (brain) microglia were detected in a prominent manner in females. Our data indicate that vitamin D deficiency produces profound modifications in microglia, suggesting a possible role of these cells in the sensorial dysfunctions associated with hypovitaminosis D.     

Spezielle Probleme bei der Vitamin D-Analytik in Futtermitteln mit HPLC

Special Problems of the Vitamin D-Analysis in Feedstuff by HPLC The protection of vitamin D by new coatings requires the saponification of the sample. The advantages of digestion at room temperature fail, for example the separation of unchanged vitamin A-esters. Saponification involves additional difficulties: the displacement of equilibrium vitamin D/previtamin D to more previtamin, the separation vitamin D from vitamin A-alcohols and the separation from citranaxanthin and canthaxanthin in poultry feedstuff. These substances interfere in HPLC by absorption at 265 nm, the absorption maximum of vitamin D. A special method for poultry feedstuff is described: 1. saponification and extraction, 2. Al₂O₃ column chromatography, 3. thin-layer chromatography, 4. reversed phase-HPLC, 5. straight phase-HPLC.     

High-Throughput Gene and Protein Analysis Revealed the Response of Disc Cells to Vitamin D,Depending on the VDR FokI Variants

Vitamin D showed a protective effect on intervertebral disc degeneration (IDD) although conflicting evidence is reported. An explanation could be due to the presence of the FokI functional variant in the vitamin D receptor (VDR), observed as associated with spine pathologies. The present study was aimed at investigating—through high-throughput gene and protein analysis—the response of human disc cells to vitamin D, depending on the VDR FokI variants. The presence of FokI VDR polymorphism was determined in disc cells from patients with discopathy. 1,25(OH)₂D₃ was administered to the cells with or without interleukin 1 beta (IL-1β). Microarray, protein arrays, and multiplex protein analysis were performed. In both FokI genotypes (FF and Ff), vitamin D upregulated metabolic genes of collagen. In FF cells, the hormone promoted the matrix proteins synthesis and a downregulation of enzymes involved in matrix catabolism, whereas Ff cells behaved oppositely. In FF cells, inflammation seems to hamper the synthetic activity mediated by vitamin D. Angiogenic markers were upregulated in FF cells, along with hypertrophic markers, some of them upregulated also in Ff cells after vitamin D treatment. Higher inflammatory protein modulation after vitamin D treatment was observed in inflammatory condition. These findings would help to clarify the clinical potential of vitamin D supplementation in patients affected by IDD.