氧化石墨烯杂化分子印迹复合膜制备及性能研究

采用改进的Hummers法,通过冷冻干燥制备了氧化石墨烯(GO)。以辛弗林盐酸盐为模板分子,水溶性的丙烯酰胺为功能单体,离子液体(溴代1-丁基-3-甲基咪唑)为致孔剂,把GO加入聚合液中,制备了GO杂化的分子印迹复合膜(GO-MIM)。利用透射电镜、扫描电镜、X射线衍射和红外光谱等方法对GO及GO-MIM进行了表征。通过将分子印迹膜技术与GO相结合,明显提高了分子印迹膜的力学性能。吸附及渗透实验表明,GO-MIM可在纯水溶剂体系,对辛弗林盐酸盐具有很好的选择性吸附能力和优先透过能力,体现了明显的分子印迹效果。     

枳实中橙皮苷与辛弗林的工业化联产工艺研究

为了提高枳实的综合利用价值,在已有的枳实中橙皮苷提取工艺的基础上,研究枳实中辛弗林与橙皮苷联产工艺。采用高效液相色谱法测定橙皮苷和辛弗林含量,枳实原料经粉碎后pH 0.3盐酸溶液浸提,滤液采用Dowex 50(H+)强酸阳离子交换、真空浓缩得到辛弗林;滤渣采用碱提酸沉的方法制得橙皮苷,对联产工艺关键参数进行优化,重复16批次联产中试。联产工艺获得的橙皮苷纯度95.0%~98.0%,提取率为24.0%~28.0%;辛弗林纯度20.0%以上,辛弗林工业化提取率3.0‰以上。与传统工艺相比,产品质量得到提高,联产工艺收益明显上升。     

Phytochemical Profile and Antioxidant Activity of Physiological Drop of Citrus Fruits

Abstract: The phytochemical content and the antioxidant activity (AA) of physiological drop of the main citrus species grown in China were investigated. Among the flavonoids, hesperidin was found mostly in mandarin and sweet orange, naringin was found mostly in sour orange, pummelo, grapefruit and a hybrid (Gaocheng), narirutin was found in most varieties, neohesperidin was found in Gaocheng and Huyou, and nobiletin and tangeretin were found in most varieties. Hydroxycinnamic acids were the main phenolic acids present, ferulic acid and caffeic acid were the dominant in most cases. There was a greater amount of free (extractable) than bound (insoluble) phenolic acids. Levels of limonoids were higher in Foyou, Eureka lemon, and Gaocheng than those in the other cultivars. The highest level of synephrine was found in Ponkan and Weizhang Satsuma. AA was highest in Ponkan and Weizhang Satsuma and lowest in Huyou, pummel, and lemon. These results suggest that physiological drop of citrus fruits have good potential as sources of different bioactive compounds and antioxidants. Practical Application: Physiological drop of citrus fruits may be a good resource of bioactive compounds including flavonoids, phenolic acids, limonoids, synephrine, and a good material of nutraceuticals.     

微波强化提取枳实中辛弗林的工艺研究

用水提取枳实中的辛弗林,结果表明,采用微波破壁在以水为溶剂,料液比为1∶8,微波破壁3次,30 s/次,pH为5.5时,辛弗林的相对提取率可达98.1%。微波破壁与传统的煎煮法相比较,具有成本低、产物收率高、可显著降低提取液中杂质含量的优点。     

Synthesis and Evaluation of Uniformly Sized Synephrine-Imprinted Microparticles Prepared by Precipitation Polymerization

Uniformly sized synephrine molecularly imprinted polymer (MIP) microparticles were prepared via precipitation polymerization. The presence of the template, the amount of monomer, crosslinker, and porogenic solvent could affect the size distribution and morphology of the polymers. The pseudo-second-order kinetic model could provide a better correlation for the adsorption than the pseudo-first-order model. The intraparticle diffusion study showed that the sorption involved intraparticle diffusion, but that was not the only rate-controlling step. The equilibrium data better fit the Freundlich model than the Langmuir model. The Scatchard plot of MIPs revealed MIPs had two groups of sites with different affinities. Subsequent recognition selectivity experiments demonstrated preferential structural selectivity for synephrine with respect to other structurally similar compounds (i.e., octopamine and tyramine). Compared with the bulk MIP of SYN, the SYN MIP microparticles in this work had higher adsorption selectivity and capacity due to their smaller particle sizes; moreover, the precipitation polymerization was time-saving due to not using a crash-and-sieve process.     

响应面法优化枳实中辛弗林的超声辅助提取工艺

在单因素试验的基础上,采用响应面法对超声波辅助提取枳实中生物碱辛弗林的工艺进行优化,预测得到最实验佳条件。结果表明：超声波法提取枳实中生物碱辛弗林的最佳工艺条件为枳实颗粒度30目、乙醇体积分数67.90%、液固比12:1(mL/g)、提取时间16min、超声功率420W,在此条件下,辛弗林的提取量达到5.87mg/g。该工艺提取结果与理论预测值5.77mg/g基本吻合,说明该优化方法可行。