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1.
Sesame(Sesamum indicum L.) is a significantly lucrative cash crop for millions of small-holder farmers. Its seeds are an important source of a highly appreciated vegetable oil globally and two clinically essential antioxidant lignans, sesamin and sesamolin. Accordingly, many countries import millions of tons of sesame seed every year. The demand for lignan-rich sesame seeds has been increasing in recent years due to the continuous discovery of several pharmacological attributes of sesamin and se...  相似文献   
2.
草莓在采收和贮运中易受损伤和病原微生物侵染而腐烂变质,影响其商品价值。为研究南五味子木脂素复合涂膜液对草莓保鲜效果的影响,以南五味子为材料,采用超声辅助乙醇浸提法提取其木脂素。以抑菌圈直径为指标,南五味子木脂素对3种供试菌的抑菌效果从强到弱为大肠埃希氏菌>沙门氏菌>金黄色葡萄球菌。考察南五味子木脂素、叶绿素铜钠、魔芋葡甘聚糖、氯化钙4个组分对草莓失重率、可溶性固形物含量、Vc含量的影响。在单因素实验基础上进行响应面优化实验,得到南五味子木脂素复合涂膜液的最优配方为0.32%木脂素+0.0021%叶绿素铜钠+0.27%魔芋葡甘聚糖+1.0%氯化钙,将制备的复合涂膜液应用于草莓贮藏实验,使用复合涂膜液的草莓的失重率下降73.86%,可溶性固形物含量提高67.55%,Vc含量提高21.80%,与对照组相比保鲜效果显著提高,可以作为草莓保鲜的技术参考。  相似文献   
3.
    采用高效液相色谱-二极管阵列检测-电喷雾质谱(HPLC-PAD-ESI-MS)法对开环异落叶松树脂酚二葡萄糖苷(SDG)进行定性和定量检测,研究方法的精密度、稳定性、定量检测限及加样回收率,并考察样品制备方法对定量检测结果的影响.采用Sephadex LH-20柱色谱分离制备SDG对照品,并用1H-NMR与13C-NMR对其进行表征.HPLC-PAD-ESI-MS检测所得紫外及电喷雾质谱信息与SDG结构相符.以自制的SDG(纯度96.6%)为对照,采用HPLC绘制定量标准曲线,方法精密度较高(RSD为1.36%),稳定性好(1周后RSD为1.21%),定量检测限较低(LOQ为3.4 mg·L-1),加样回收率达(99.7±3.2)%.此外,制样时采用碱法水解与混合溶剂提取,不仅节省时间,还更充分地提取了SDG.说明用HPLC-PAD-ESI-MS法栓测亚麻籽中的SDG方便省时,准确可靠.  相似文献   
4.
Thymelaeaceae plants produce dextrorotatory dibenzylbutyrolactone lignans, which are opposite enantiomers to the lignans isolated from other plants (e.g.,Forsythia spp.). In our previous paper, (–)-pinoresinol (74% enantiomer excess), (+)-matairesinol (optically pure), and (+)-wikstromol (optically pure) were isolated fromWikstroemia sikokiana (Thymelaeaceae). In the present investigation, a survey of lignans and the determination of their enantiomeric compositions were continued. Four lignans, (–)-lariciresinol, (–)-secoisolariciresinol, (+)-kusunokinin, and (+)-methyltrachelogenin, were isolated from MeOH extracts ofW. sikokiana stem. To our knowledge, we have isolated (+)-methyltrachelogenin from plants for the first time. Chiral high-performance liquid chromatographic analysis showed that (+)-kusunokinin and (+)-methyltrachelogenin were optically pure, whereas (–)-lariciresinol and (–)-secoisolariciresinol were not (39% and 45% enantiomer excess, respectively). Feeding experiments with deuterium-labeled substrates demonstrated conversion of coniferyl alcohol to the lignans and interconversion of lignans. These reaction sequences are similar to the sequence catalyzed byForsythia enzymes. However, predominant enantiomers of the lignans, except for secoisolariciresinol isolated fromW. sikokiana, have absolute configurations opposite to those of the corresponding lignans isolated fromForsythia spp. Based on the results of the isolation and the feeding experiments, several differences betweenW. sikokiana andForsythia spp. are pointed out regarding stereochemical mechanisms for lignan biosynthesis.Parts of this report were presented at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 1996; and the 47th annual meeting of the Japan Wood Research Society, Kochi, April 1997  相似文献   
5.
BACKGROUND: In a search for plant extracts with potent in vivo antifungal activity against various plant diseases, we found that treatment with a methanol extract of Myristica fragrans Houttyn (nutmeg) seeds reduced the development of various plant diseases. The objectives of the present study were to isolate and determine antifungal substances from My. fragrans and to evaluate their antifungal activities. RESULTS: Three antifungal lignans were isolated from the methanol extract of My. fragrans seeds and identified as erythro-austrobailignan-6 (EA6), meso-dihydroguaiaretic acid (MDA) and nectandrin-B (NB). In vitro antimicrobial activity of the three lignans varied according to compound and target species. Alternaria alternata, Colletotrichum coccodes, C. gloeosporioides, Magnaporthe grisea, Agrobacterium tumefaciens, Acidovorax konjaci and Burkholderia glumae were relatively sensitive to the three lignans. In vivo, all three compounds effectively suppressed the development of rice blast and wheat leaf rust. In addition, EA6 and NB were highly active against the development of barley powdery mildew and tomato late blight, respectively. Both MDA and NB also moderately inhibited the development of rice sheath blight. CONCLUSION: This is the first study to demonstrate the in vitro and in vivo antifungal activities of the three lignans from My. fragrans against plant pathogenic fungi.  相似文献   
6.
五味子属药用植物木脂素的研究现状与展望   总被引:1,自引:0,他引:1  
木脂素是五味子属药用植物的主要生物活性成分,其成分、含量与植物器官、部位、产地、生长季节、提取工艺及测定方法等有很大关系,本文中就其研究现状及展望进行探讨,为五味子属药用植物的木脂素类化合物开发利用及质量标准的制定提供参考。  相似文献   
7.
 【目的】研究中国新育油用亚麻品种(系)木酚素含量与基因型和地点的关系。【方法】用高效液相色谱(HPLC)测定11个油用亚麻品种(系)2005、2006年在4个代表性试点的木酚素含量。【结果】11个亚麻品种(系)88点次木酚素含量变幅为6.487~13.127 mg?g-1,以97047平均含量最高,伊04的最低;4个地点中以河北坝上点最高,新疆伊犁点最低。方差分析表明,基因型、地点以及基因型×地点互作效应对木酚素含量的影响均达到1%显著水平。不同品种(系)木酚素含量的稳定性存在明显差异,以97047和伊04的稳定性好。【结论】基因型是影响木酚素含量的首要因子,品种选育是提高木酚素含量的首选措施。不同品种有不同的适种地区,参试品种(系)中97047为木酚素含量高且适应性广泛的品种(系)。  相似文献   
8.
亚麻籽木脂素研究进展   总被引:8,自引:0,他引:8  
广泛存在于植物界的木脂素类化合物,能通过动物机体内微生物转化成动物木脂素,具有雌激素样和抗雌激素样生物活性.大量研究表明,动物木脂素及其在植物中的前体物质具有抗癌、抗氧化、抗心血管系统疾病等临床应用价值,且能通过与性激素受体结合等途径发挥其他生理作用,因而在动物生产领域有着重要的应用价值.很多学者就木脂素的检测方法、代谢转化、保健和生理学功能进行了研究.在各种植物籽实中,亚麻籽中的木脂素含量最高,而亚麻是我国北方广泛种植的经济作物,开发和利用亚麻籽木脂素将带来良好的经济和社会效益.  相似文献   
9.
【目的】研究乙醇体积分数、超声时间、液固比及其交互作用对五味子种子木脂素提取率的影响,并优化其提取工艺。【方法】以木脂素提取率为考察指标,选取乙醇体积分数、超声波提取时间和液固比为因素,进行单因素试验;然后在单因素试验基础上确定因素和水平进行中心组合设计试验,应用SAS 9.1软件和响应面分析相结合的方法,模拟木脂素提取率回归方程的预测模型,验证优化得到的最佳提取条件。【结果】五味子种子木脂素的优化提取工艺为:乙醇体积分数73%,超声时间32min,液固比299mL/g。在此条件下,经过多次验证试验,发现木脂素提取率为2.47%,与理论值(2.59%)十分接近。【结论】利用中心组合设计试验优化获得了五味子种子木脂素的超声提取工艺,为其工业化提取提供了参考。  相似文献   
10.
为优化油用亚麻营养品质检测方法,提高育种效率,利用无损近红外光谱分析法定量分析亚麻籽粒蛋白质、亚麻酸和木酚素含量,初步探讨蛋白质、亚麻酸和木酚素含量相关性.以具有代表性的200份亚麻籽为研究对象,采集近红外光谱,使用偏最小二乘法和净分析信号光谱预处理建立了蛋白质、亚麻酸和木酚素含量近红外模型.结果表明:亚麻籽蛋白质、亚...  相似文献   
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