Gene Discovery in Gelsemium Highlights Conserved Gene Clusters in Monoterpene Indole Alkaloid Biosynthesis

Genome mining is a routine technique in microbes for discovering biosynthetic pathways. In plants, however, genomic information is not commonly used to identify novel biosynthesis genes. Here, we present the genome of the medicinal plant and oxindole monoterpene indole alkaloid (MIA) producer Gelsemium sempervirens (Gelsemiaceae). A gene cluster from Catharanthus roseus, which is utilized at least six enzymatic steps downstream from the last common intermediate shared between the two plant alkaloid types, is found in G. sempervirens, although the corresponding enzymes act on entirely different substrates. This study provides insights into the common genomic context of MIA pathways and is an important milestone in the further elucidation of the Gelsemium oxindole alkaloid pathway.     

Simultaneous Microwave Extraction and Separation of Volatile and Non-Volatile Organic Compounds of Boldo Leaves. From Lab to Industrial Scale

Microwave extraction and separation has been used to increase the concentration of the extract compared to the conventional method with the same solid/liquid ratio, reducing extraction time and separate at the same time Volatile Organic Compounds (VOC) from non-Volatile Organic Compounds (NVOC) of boldo leaves. As preliminary study, a response surface method has been used to optimize the extraction of soluble material and the separation of VOC from the plant in laboratory scale. The results from the statistical analysis revealed that the optimized conditions were: microwave power 200 W, extraction time 56 min and solid liquid ratio of 7.5% of plants in water. Lab scale optimized microwave method is compared to conventional distillation, and requires a power/mass ratio of 0.4 W/g of water engaged. This power/mass ratio is kept in order to upscale from lab to pilot plant.     

响应面优化荷叶生物碱盐提取工艺

在单因素试验的基础上,利用响应面分析法对荷叶生物碱盐的提取工艺进行优化。研究加热回流法的提取温度、提取时间、料液比、磷酸体积分数对荷叶生物碱盐提取效果的影响。结果表明,提取最佳工艺条件为提取温度92.7℃、提取时间2.28h、料液比1:24.4(g/mL)、磷酸体积分数0.27%,在此条件下,荷叶生物碱盐的提取率可达5.313mg/g,与理论预测值5.372mg/g的相对误差为1.11%,说明该模型具有较好的分析能力。     

番荔枝宁合成工艺

以3,4-二甲氧基苯乙腈为起始原料,分别由水解和氢化还原制备3,4-二甲氧基苯乙酸和3,4-二甲氧基苯乙胺,二者经酰化、Bischler-Napieralski环化、硼氢化钾还原制得中间体四氢罂粟碱,后同甲醛经Pictet-Spengler反应制得(±)-番荔枝宁。该法合成番荔枝宁的总收率为47%。     

Discovery and development of synthetic tricyclic pyrroloquinone (TPQ) alkaloid analogs for human cancer therapy

Natural products and their derivatives represent a rich source for the discovery and development of new cancer therapeutic drugs. Bioactive components derived from natural sources including marine compounds have been shown to be effective agents in the clinic or in preclinical settings. In the present review, we present a story of discovery, synthesis and evaluation of three synthetic tricyclic pyrroloquinone (TPQ) alkaloid analogs as cancer therapeutic agents. Chemical synthesis of these compounds (BA-TPQ, TBA-TPQ, and TCBA-TPQ) has been accomplished and the mechanisms of action (MOA) and structure-activity relationships (SAR) have been investigated. In the past, the complexity of chemical synthesis and the lack of well-defined MOA have dampened the enthusiasm for the development of some makaluvamines. Recent discovery of novel molecular targets for these alkaloids (unrelated to inhibition of Topoisomerase II) warrant further consideration as clinical candidates in the future. In addition to the establishment of novel synthetic approaches and demonstration of in vitro and in vivo anticancer activities, we have successfully demonstrated that these makaluvamines attack several key molecular targets, including the MDM2-p53 pathway, providing ample opportunities of modulating the compound structure based on SAR and the use of such compounds in combination therapy in the future.

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白肋烟烟碱转化及烟草特有亚硝胺形成

从烟草特有亚硝胺形成的化学,烟草特有亚硝胺与前体物的关系,调制过程、贮藏过程中烟草特有亚硝胺的形成,遗传改良降低烟碱转化和烟草特有亚硝胺,生物技术抑制烟碱转化降低烟草特有亚硝胺等方面综述了最新研究进展.     

沙棘籽粕生物碱的提取分离及对乳鼠心肌细胞损伤的保护作用

目的：研究沙棘籽粕中生物碱的提取分离及其对乳鼠心肌细胞缺血/ 再灌注损伤的保护作用。方法：用乙醇提取、利用多种柱层析分离手段从沙棘籽粕中分离单体化合物,采用质谱、核磁共振法鉴定其结构;采用乳鼠心肌细胞缺血/ 再灌注损伤模型,利用MTT 法测定心肌细胞存活率,检测乳酸脱氢酶(LDH)、肌酸激酶(CK)含量以反映心肌细胞受损的程度。结果：从沙棘籽粕分离得到SJ-A- Ⅰ组分,经鉴定为生物碱5,11- 二羟基色胺;该物质能有效维持心肌细胞活力,减少培养心肌细胞缺血/ 再灌注损伤所致心肌酶(LDH、CK)的释放。结论：沙棘籽粕中的生物碱5,11-二羟基色胺对乳鼠心肌细胞缺血/再灌注损伤具有明显的保护作用,其最佳质量浓度为150mg/L。     

荷叶生物碱柱分离纯化技术研究

以荷叶干叶为原料,经30%乙醇提取后,通过对聚酰胺、D101、HP-20三种大孔树脂对荷叶生物碱静态吸附与解吸的比较,在筛选出一种具有较高吸附率与解吸量树脂的基础上,比较研究了不同洗脱流速下不同乙醇浓度梯度洗脱对生物碱洗脱量、纯度和得率的影响以及最优流速下不同乙醇浓度等梯度洗脱对生物碱洗脱量、纯度和得率的影响。结果表明,树脂D101是三种树脂中分离纯化荷叶生物碱的最佳树脂,利用树脂D101分离纯化荷叶生物碱时,以流速为1.50BV/h依次经3BV的20%、40%、60%和80%乙醇进行梯度洗脱的技术参数较好,其生物碱总量、总得率和总纯度最高,分别达到10.8226mg、62.9%和4.86%,当单独收集80%乙醇浓度以上的洗脱液时,荷叶生物碱的纯度可达32.56%,可以制备较高纯度的荷叶生物碱。     

酸性醇回流法提取魔芋中的总生物碱研究

研究了用酸性醇回流法提取魔芋中总生物碱的方法和条件。结果表明,提取魔芋中总生物碱较佳的工艺条件是:在pH值为2～3的酸性醇溶液中,回流提取3h,总生物碱的含量可达0.39%。