水溶剂红花油合成共轭亚油酸研究——(I) 工艺优化研究

传统油脂共轭反应制备共轭亚油酸多采用有机溶剂,这种工艺存在溶剂残留等潜在问题。研究了红花油以水为溶剂的碱性异构化合成共轭亚油酸反应,考察了反应温度、时间、水油比、油碱比对共轭反应的影响,得到工艺条件的数学模型。反应的最佳条件为反应温度214℃,反应时间4.9h,水油比=4.3,油碱比=1.3。在此条件下,反应转化率可达到97.64%。     

Profiling of the Molecular Weight and Structural Isomer Abundance of Macroalgae-Derived Phlorotannins

Phlorotannins are a group of complex polymers of phloroglucinol (1,3,5-trihydroxybenzene) unique to macroalgae. These phenolic compounds are integral structural components of the cell wall in brown algae, but also play many secondary ecological roles such as protection from UV radiation and defense against grazing. This study employed Ultra Performance Liquid Chromatography (UPLC) with tandem mass spectrometry to investigate isomeric complexity and observed differences in phlorotannins derived from macroalgae harvested off the Irish coast (Fucus serratus, Fucus vesiculosus, Himanthalia elongata and Cystoseira nodicaulis). Antioxidant activity and total phenolic content assays were used as an index for producing phlorotannin fractions, enriched using molecular weight cut-off dialysis with subsequent flash chromatography to profile phlorotannin isomers in these macroalgae. These fractions were profiled using UPLC-MS with multiple reaction monitoring (MRM) and the level of isomerization for specific molecular weight phlorotannins between 3 and 16 monomers were determined. The majority of the low molecular weight (LMW) phlorotannins were found to have a molecular weight range equivalent to 4–12 monomers of phloroglucinol. The level of isomerization within the individual macroalgal species differed, resulting in substantially different numbers of phlorotannin isomers for particular molecular weights. F. vesiculosus had the highest number of isomers of 61 at one specific molecular mass, corresponding to 12 phloroglucinol units (PGUs). These results highlight the complex nature of these extracts and emphasize the challenges involved in structural elucidation of these compounds.     

水溶剂红花油合成共轭亚油酸研究--(Ⅰ)工艺优化研究

传统油脂共轭反应制备共轭亚油酸多采用有机溶剂,这种工艺存在溶剂残留等潜在问题。研究了红花油以水为溶剂的碱性异构化合成共轭亚油酸反应,考察了反应温度、时间、水油比、油碱比对共轭反应的影响,得到工艺条件的数学模型。反应的最佳条件为:反应温度214℃,反应时间4.9h,水油比=4.3,油碱比=1.3。在此条件下,反应转化率可达到97.64%。     

异龙脑常压催化异构化反应的研究

研究异龙脑在常压下被含锌或含铜催化剂催化的液相和气相异构化反应,讨论了反应条件对产物分布的影响。     

Alterations in lycopene concentration and Z‐isomer content in egg yolk of hens fed all‐E‐isomer‐rich and Z‐isomer‐rich lycopene

Effects of feeding lycopene isomers to laying hens on egg qualities such as lycopene concentration and color of the yolk were investigated. Firstly, to evaluate the dietary transfer of lycopene to egg yolk, (all‐E)‐lycopene–rich diets (lycopene content, 100, 200, or 300 mg/kg diet) were fed to hens for 21 days. Lycopene in egg yolk could be detected after 4 days or more from the start of feeding, and the lycopene concentration increased according to the feed amount and period. Even though most of the dietary lycopene was the all‐E‐isomer, more than 65% of lycopene in egg yolk was present as Z‐isomers. Thus, the effect of lycopene Z‐isomer content in the diet (lycopene content, 200 mg/kg diet; lycopene Z‐isomer content, 35.1% or 61.3%) on egg qualities was investigated. As the Z‐isomer content increased, the lycopene concentration in the egg yolk increased, for example, when fed a diet rich in Z‐isomers (61.3%), the lycopene concentration in the egg yolk was approximately three times higher than when fed the (all‐E)‐lycopene–rich diet for 21 days. The results indicated that Z‐isomers of lycopene had higher bioavailability and/or higher transfer efficiency to the egg yolk than the all‐E‐isomer.     

八面沸石在精细有机合成中的催化作用--DUSY 催化α-蒎烯异构的动力学特征

研究了脱铝超稳Y沸石催化α 蒎烯异构化反应的动力学特征。考察了催化剂硅铝比及反应条件对转化率、产物分布的影响。动力学研究表明 ,以四氢呋喃作溶剂 ,α 蒎烯在DUSY 1(SiO2 /Al2 O3=7.4 1)催化剂上的异构化服从准一级动力学模型 ,并经最小二乘法处理数据得反应的表观活化能为 144 .3kJ/mol。     

松香中枞酸型树脂酸在酸作用下变化规律的研究

选用湿地松松香和马尾松松香,不同种类的酸作用不同时间,分析了酸作用对枞酸型树脂酸和去氢枞酸含量变化的影响,研究了枞酸型树脂酸在酸作用下的变化规律。结果表明：在酸处理过程中,长叶松酸、枞酸、新枞酸之间发生相互异构,同时还有脱氢反应和脱羧等裂解反应发生,异构速度、脱氢速度和脱羧速度都与酸的种类、酸强度和反应时间有关。酸强度越大,异构速度、脱氢速度和脱羧速度越快。     

顺式菊酸的异构化反应

顺反混合菊酸(顺/反=43/57),用氢氧化钠-乙二醇处理,反应产物经~1HNMR 测定表明:反式异构体的含量可达95%,反应收率为86%。     

戊内酯/水体系中磷钨酸铝催化葡萄糖转化制备5-HMF

利用离子交换技术制备了催化剂磷钨酸铝(AlPW12O40),采用FT-IR、XRD、电位滴定和ICP技术对催化剂AlPW12O40进行了系统表征.在水热条件下,对AlPW12O40催化葡萄糖转化制备5-羟甲基糠醛(5-HMF)进行了研究,考察了反应温度、时间、催化剂用量和溶剂配比对5-HMF得率的影响.研究结果表明:在...     

多聚磷酸催化罗汉柏木烯异构化反应工艺

以柏木油为原料,对柏木油中罗汉柏木烯异构化生成Olefin B的催化剂种类及影响因素进行了对比研究。结果表明,以多聚磷酸为催化剂,质量比为柏木油∶冰醋酸∶多聚磷酸=45∶18∶8,反应温度为50℃,反应时间为3 h,Olefin B含量可达10.3%,产率25.8%。