多功能食品添加剂棓酸烷醇酯的合成及性能研究

木立口 酸丙酯 (PG)、异丙酯 (iPG)、丁酯 (BG)、异丁酯 (iBG)及十二烷醇酯 (DG)均采用对甲苯磺酸作催化剂 ,以梯度升温法合成。PG的合成还革除了带水剂。最佳合成条件 ,PG :n(酸 )∶n(醇 )∶n(催化剂 ) =0 .0 82 5∶0 .934∶0 .0 0 5 2 4,反应温度 12 0℃ ,反应时间 2h ,收率 94.2 % ;BG和iBG :n(酸 )∶n(醇 )∶n(催化剂 ) =0 .0 5 2 2∶0 .874∶0 .0 0 394,反应温度 115～ 12 0℃ ,反应时间 5h ,收率分别为 86 .8%和 83.9% ;DG :以 1,4 二氧六环作溶剂 ,4A分子筛作吸水剂 ,n(酸 )∶n(醇 )∶n(催化剂 ) =0 .0 75∶0 .0 91∶0 .0 12 ,反应温度 12 4℃ ,反应时间 14h ,收率 93.7% ;iPG :采用干燥氯化氢作催化剂 ,n(酸 )∶n(异丙醇 ) =0 .147∶1.34,加热回流 8h ,收率 88.1%。研究了木立口 酸烷醇酯(AG)在花生油中的抗氧化性能 ,其抗氧化活性顺序为DG >BG >PG ,直链烷醇酯与支链烷醇酯的抗氧化活性无明显区别。AG对血小板聚集有对抗作用 ,药理活性与其抗氧化活性呈平行关系。

Synthesis of Polyfunctional Food Additives Alkyl Gallates and Study of Their Performance

For the synthesis of ethyl,propyl,isopropyl,butyl,isobutyl and dodecyl esters of gallic acid, p toluenesulfonic acid was used as catalyst instead of concentrated sulfuric acid and the reaction temperature was raised by a gradient style.Propyl gallate was synthesized without water carrying agent.The optimum synthetic conditions were determined.At a molar ratio of acid to alcohol to catalyst 0.0825∶0.934∶0.00524,reaction temperature 120 ℃ and reaction time 2 h,the average yield of PG was 94.2%.At molar ratio of acid to alcohol to catalyst 0.0522∶0.874∶0.00394,reacting at 115-120 ℃ for 5 h,yields of BG and i BG were 86.8% and 83.9% respectively.At molar ratio of acid to alcohol to catalyst 0.075∶0.091∶0.012,reacting at 124 ℃ for 14 h with 1,4 dioxane as solvent and 4A molecular sieve as water absorbing agent,DG was given in 93.7% yield.iPG was given in the presence of dry hydrogen chloride as catalyst in 88.1% yield under refluxing for 8 h and at molar ratio of acid to alcohol 0.147∶1.34.The antioxidative activity of alkyl gallates(AG) was studied with peanut oil.The results showed that the sequence of antioxidative activity of AG was DG>BG>PG>EG,but there was little difference between i PG and PG or i BG and BG.AG possesed the activity of antibloodplatelet aggregation.The sequence of that was parallel with the antioxidative activity of AG.