三棕榈酸甘油酯 、 维生素 C 在
Lipozyme TL IM 作用下,
以
2-甲基-2-丁醇 为溶剂,
以50%的产率得到[(2S)-2-[(2R)-4,5-二羟基-3-氧代呋喃-2-基]-2-羟基乙基](Z)-十八碳-9-烯酸酯
参考文献:
名称:
甘油三酸酯为酰基供体的Lipozyme TL IM催化合成抗坏血酸酯
摘要:
AbstractEsters of l‐ascorbic acid with long‐chain fatty acids (E‐304) are employed as antioxidants in foods rich in lipids. Although their enzymatic synthesis offers some advantages compared with the current chemical processes, most of the reported methods employ the immobilized lipase from Candida antarctica as biocatalyst and free fatty acids or activated esters as acyl donors. In order to diminish the cost of the process, we have investigated the synthesis of ascorbyl oleate and ascorbyl palmitate esters with the immobilized Thermomyces lanuginosus lipase Lipozyme TL IM—which is significantly less expensive than Novozym 435—and triglycerides as source of fatty acids. Lipozyme TL IM gave rise to a lower yield of 6‐O‐ascorbyl oleate than Novozym 435 when using triolein (64 vs. 84%) and olive oil (27 vs. 33%) as acyl donors. Both 6‐O‐ascorbyl oleate and 6‐O‐ascorbyl palmitate displayed excellent surfactant and antioxidant properties. The Trolox Equivalent Antioxidant Capability values for the oleate and palmitate were 71 and 84%, respectively, of those obtained with l‐ascorbic acid; however, both derivatives were able to stabilize soybean oil towards peroxide formation.
Enzymatic synthesis and anti-oxidative activities of plant oil-based ascorbyl esters in 2-methyltetrahydrofuran-containing mixtures
作者:Ying-Dan Hu、Min-Hua Zong、Ning Li
DOI:10.1080/10242422.2016.1247820
日期:2016.7.3
Abstract Ascorbyl fatty acid esters are commercially interesting fat-soluble antioxidants. In this work, enzymaticsynthesis of ascorbylesters from less expensive and readily available plant oils, and their anti-oxidative activities are described. Among the immobilized lipases tested, Candida antarctica lipase B was the best for the synthesis of plant oil-based ascorbylesters. The enzyme showed much
AbstractSaturated acyl (6‐O‐caproyl, lauroyl, and myristoyl) and unsaturated acyl (6‐O‐oleoyl, linoleoyl, and arachidonoyl) l‐ascorbates were continuously synthesized at 50°C using a system where a column packed with ascorbic acid powder and a packed‐bed reactor with an immobilized lipase from Candida antarctica were connected in series. A productivity of 1.6–1.9 kg/L reactor·d was achieved for at least 11 d. The surface tension of the caproyl or lauroyl l‐ascorbate in aqueous solution was measured at various temperatures and pH to estimate the critical micelle concentration (CMC) of the acyl l‐ascorbate. The CMC values were independent of temperature but dependent on the pH. The value of the caproyl ascorbate increased with an increase in pH.
Antioxidative properties and enzymatic synthesis of ascorbyl FA esters
作者:Fredrik Viklund、Jari Alander、Karl Hult
DOI:10.1007/s11746-003-0774-1
日期:2003.8
AbstractEfficient synthesis of unsaturated FA esters of ascorbic acid is possible with only a small excess of one of the reactants in t‐amyl alcohol using Candida antarctica lipase as biocatalyst. Using free acids, we obtained yields that were comparable to yields reached using vinyl‐activated acyl donors (71, 80, and 86% yields of esters with FA excesses of 1∶1, 1∶1.5, and 1∶2, respectively). As very low water activity is needed to achieve sufficiently high yields of product, molecular sieves were used to improve the ascorbyl ester yields. Ascorbyl oleate is more amorphous and has a much lower m.p. and lower enthalpy of fusion than ascorbyl palmitate. This leads to a higher solubility of ascorbyl oleate in oil, resulting in an increased antioxidant effect compared to that of the palmitate. In an accelerated storage test using deodorized rapeseed oil, samples incubated with ascorbyl palmitate showed noticeable oxidation after 1 wk of storage, whereas samples incubated with ascorbyl oleate displayed negligible oxidation for 9 and 4 wk at 30 and 40°C, respectively.
CONVENIENTLY INJECTABLE OR IMPLANTABLE SUSTAINED-RELEASE ANTIOXIDANT FORMULATIONS FOR THERAPIES OF OCULAR MALADIES OR CANCER
申请人:Ramscor, Inc.
公开号:EP2717866A2
公开(公告)日:2014-04-16
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