Decursin Safety from Root of Angelica gigas in Rats

The subacute intraperitoneal toxicity of decursin was investigated in Spargue-Dawly（SD） rats. The rats were treated with decursin at a dose of 125 and 250 mg·kg-1·day-1for 4 weeks. All animals were observed daily for clinical signs. Their body weights were recorded weekly, no mortality was observed in two doses of 125 and 250 mg·kg-1of decursin. There were no significant differences in the clinical observations, body weight, food and water consumption, hematology, blood chemistry, gross pathological examination or organ weight between control and treated animals of both sexes. In conclusion, no evidence of a subacute toxic potential was observed in this study and no indication for adverse effects was noted at a dose level of 250 mg·kg-1·day-1.     

In vitro and in vivo antifungal activities of decursin and decursinol angelate isolated from Angelica gigas against Magnaporthe oryzae, the causal agent of rice blast

Blast is considered the most important fungal disease of rice due to its wide distribution and destructiveness under favorable conditions. Development of new effective and environmentally benign agents against the causal pathogen, Magnaporthe oryzae, is of great interest. In the course of a search for natural antifungal compounds in medicinal plants, we found that the methanol extract of Angelica gigas roots showed a potent control efficacy against rice blast caused by M. oryzae. We isolated antifungal coumarins from the extract, and they were identified as decursin and decursinol angelate. Antifungal activities of these compounds, along with kasugamycin, were tested on M. oryzae in vivo and in vitro. In an in vivo assay, the three compounds effectively suppressed the development of rice blast at concentrations more than 100 μg/mL. Coumarins showed relatively weak inhibitory effect on fungal mycelial growth when compared to kasugamycin. However, they strongly inhibited M. oryzae spore germination, which was not observed in kasugamycin treatments. This is the first report demonstrating that decursinol angelate can provide control against rice blast and that the two coumarins inhibit M. oryzae spore germination. In addition, the wettable powder formulation of the crude extract of A. gigas prohibited the development of blast symptoms on rice plants more effectively than liquid concentrate formulation of kasugamin, a commercial fungicide. Based on our study, we propose that coumarin compounds as well as the A. gigas root crude extract can be used as natural, benign fungicides for controlling rice blast.     

虾蛄蛋白浆对河蟹摄食和生长影响的研究

分别用虾蛄蛋白浆替代饲料中2%和4%的鱼粉,并以乌贼膏为对照,研究其对河蟹摄食和生长的影响。结果表明,饲料中添加虾蛄蛋白浆对河蟹的诱食作用与乌贼膏相当,但摄食量显著高于乌贼膏组。此外,虾蛄蛋白浆还具有明显的促进河蟹脱壳生长的作用,其作用机制可能与其中氨基酸、小肽、胆固醇等含量丰富有关。     

甘肃岷县不同海拔栽培当归多糖含量比较研究

目的：对甘肃岷县不同海拔区域栽培当归多糖含量进行测定,探索当归多糖含量与栽培区域海拔之间的关系。方法：加热回流提取当归多糖,苯酚-浓硫酸法比色,在490 nm处以紫外分光光度法测定其吸光度,对照标准曲线计算样品多糖含量。结果：当归多糖在2 300-2 900 m区域内随海拔升高含量逐渐增高,在海拔2 900-3 100 m区域内随海拔升高含量逐渐下降,其中2 600-2 900 m海拔区域栽培当归样品多糖含量明显高于其他海拔区域当归多糖含量。结论：本研究探讨了当归多糖含量随栽培区域海拔的变化规律,对当归最适栽培区域的选择具有一定参考价值。     

不同产地当归药材中阿魏酸含量比较研究

目的：考察不同产地当归药材中阿魏酸含量的差异。方法：采用高效液相色谱法对18批不同产地的当归药材中阿魏酸进行含量测定。结果：阿魏酸在0.24-3.12μg/mL范围内线性关系良好;平均加样回收率为100.7%,RSD 1.2%。不同产地当归药材中的阿魏酸含量差异较大,云南产最高,甘肃次之,四川较低,其中道地产区岷县处于中等水平。结论：以单一指标成分阿魏酸来评价当归药材质量不够全面,需要进一步研究多指标成分,以有效评价当归药材质量。     

高寒区轮作模式对当归田土壤特性及药材产量的影响

连作重茬造成当归产量逐年下降。采用药用植物秦艽(QJ)、羌活(QH)轮作当归(DG),以当归连作为对照,通过测定土壤和药材产量指标,利用主成分分析确定各指标权重,并结合隶属综合因子分析和聚类分析,旨在揭示不同药用作物轮作当归对土壤环境与药材产量的影响,为筛选适宜当归栽培的轮作模式提供科学依据。结果表明,不同作物轮作对当归田土壤特性和药材产量均具有显著影响,秦艽轮作当归可有效改善土壤特性,使当归成药期土壤磷和钾含量处于较低水平,而有机质维持在较高水平,对土壤水分的季节调控作用更为显著,与当归连作相比较,当归成药率提高94.10%,药材单根鲜重和药材鲜产量分别提高53.46%和125.56%,而羌活轮作当归土壤pH最高,有机质含量最低,当归连作土壤有机质含量虽高,但土壤富集磷和钾,对土壤水分季节性调控作用最小,当归成药率和药材产量均低。不同轮作模式当归成药率和药材产量依次为秦艽-当归>当归-当归>羌活-当归,综合指数大小依次为秦艽-当归(0.8132)>羌活-当归(0.3315)>当归连作(0.2051)。聚类分析将3种轮作模式分为三大类,重复小区亚类间距离均小,说明不同作物轮作对土壤的调控作用不同,高寒产区秦艽轮作当归是优化调控土壤环境,提高当归产出性能的有效轮作模式。     

白芷黑斑病病原菌鉴定及病害发生规律研究

对四川白芷黑斑病的症状、病原菌致病性和形态特征等进行了研究,确定病原菌为当归叶点霉(PhyllostictaangelicaeSaccardo)。经两年的田间病害发生动态调查,该病在四川始发期为3月上旬,高峰期为6月份,病株率达100%,病叶率达74.51%。病害的初侵染源主要是留种株的病叶和田间病残体。病菌分生孢子借雨滴飞溅的方式传播,并在白芷生长期中不断引起再侵染。     

施氮水平对青海中华羊茅产量和营养成分含量的影响

在高寒地区旱作条件下种植青海中华羊茅最适施氮量为N60kg/hm^2,施肥后三年内产草量比对照提高23.62%,其增产值是施肥成本的2.37倍,产籽量提高12.38%,其增产值是施肥成本的4.97倍。青海中华羊茅的产量随着施氮量的增加而增加,施氮后第二年的增产量高于施肥当年的增产量。粗蛋白质含量随着施氮量的增加而增加,但其增加速度随着施氮量的增加而减少,无氮浸出物的含量则随着施氮量的增加而急剧减少,而减少的速度随着施氮量的增加而减小。     

当归根中扑草净残留分析

针对当归栽培过程中筛选出的适宜除草剂扑草净进行残留分析和测定,以确定当归栽培过程中使用化学除草剂的可行性,确立当归地化学除草造成除草剂残留的分析方法,为建立规范化(SOP)当归生产体系提供标准和依据.结果表明,当归干燥根中存在扑草净残留,剂量约为0.42 mg/kg.     

岷县当归产地鉴别与利用前景

由于地理环境影响,岷县当归与其他产地当归在主要成分及其含量上存在差异,道地药材岷县当归的鉴别方法有性状鉴别、组织鉴别、显微结构鉴别、指纹图谱鉴别和rRNA鉴别等。近年研究表明,当归有效成分在血液系统、免疫系统、神经系统等方面具有广泛药理作用,为其临床运用提供了依据。超临界CO2萃取当归有效成分克服了以往的提取法固有的弱点,从当归提取剩余物提取膳食纤维在理论和现实上的可能性为膳食纤维开辟了新的来源．