茵陈蒿的三种不同溶剂提取物对赤拟谷盗作用方式和作用效果的研究

用茵陈蒿三种不同溶剂(丙酮、乙醇和乙酸乙酯)提取物对赤拟谷盗进行生物活性测定，结果表明，茵陈蒿乙醇提取物对试虫的触杀作用和驱避作用较好，其5倍液在处理后72小时，对赤拟谷盗成虫校正死亡率和驱避率分别为57．8％和91．6％。     

Soil Microbial Biomass Under the Canopy of Coastal Sand Dune Shrubs

Coastal sand dunes are affected by seasonal fluctuations in salinity due to seawater spray and precipitation. Salinity was found to be very high in summer soil samples and was about 15-20 times lower in the preceding rainy winter. High microbial biomass values of 234.6 and 173.1 mugC g-1 dry soil were found under Artemisia monosperma and Retama raetam, respectively, even at elevated salinity. The metabolic quotient for CO2, which may serve as an indicator for changes in microbial diversity or environmental stress, was unexpectedly high (58.5 and 48.8 mug mg-1 d-1 under A. monosperma and R. raetam, respectively) in low-saline samples from the winter when compared to the summer (a maximal value of 20 mug mg-1 d-1), probably indicating a shift in community structure. It may be concluded that even under hostile conditions in poor sandy soils and with high salinity the presence of perennial shrubs creates favorable niches for microorganisms and affects their activity.     

U.l.v. Application of Bioresmethrin by Helicopter for Musca Control in Saudi Arabia

Abstract

A six hundred hectare township in Saudi Arabia was sprayed by a Micronair equipped helicopter with approximately 11 g of bioresmethrin in 550 ml solvent per hectare, applied in the early morning, on one occasion only, in order to evaluate the technique for fly control. The kill of caged wild flies (Musca domestica nebulo F.) in the open was complete. However, sticky traps and Scudder grill counts indoors indicated only 69% and 72% reduction of fly density. Although coverage by aerial application was found to be accurate, penetration into such areas as covered markets was poor, and therefore the method can only be recommended as an adjunct to ground based operations.     

Effects of Topographic Factors of the Site on the Essential Oil Compounds of Artemisia aucheri Aerial Parts Grown in a Mountainous Region

In this study, the chemical compositions of the essential oils from the aerial parts of Artemisia aucheri, grown in a mountainous region in Ghamsar Province, central Iran, have been analyzed by using gas chromatography (GC)–mass spectroscopy (MS) to determine how they are affected by topographic factors (site direction and elevation). Plants were sampled at random in full flowering stage in a completely randomized (CR) design with three replications. The essential oil was extracted by a modified Likens–Nickerson's simultaneous distillation–extraction (SDE) technique. Analysis of the plant oils on the sites [in two directions, north–south (N/S) and east–west (E/W)] and five elevations resulted in 30 identified compounds. Of the oil samples collected, the 99.94% of the components at the N/S site and 99.89% at the E/W site were identified. The main component in the two directions (N/S and E/W) was α-thujone with 19.5% and 18%, respectively. Other significant components in the two directions include α-pinene, davanone, camphor, and camphene. The percentages of all these main compounds on the N/S site were more than on the E/W site. Also, the main compounds increased with increasing altitude and at all five elevations. Among all the oil compounds, the percentages of α-thujone, α-pinene, and camphor were the greatest. Finally, at all the elevations, the percentage of the α-thujone was the greatest among the different oil compounds.     

炭化温度对沙蒿生物炭形貌特征和化学性质的影响

沙蒿是半灌木典型沙生植物,作为制炭物料具有其特殊性,而炭化温度决定生物炭形貌特征和化学性质。通过无氧炭化法制备了不同温度(300~900℃)的沙蒿生物炭,研究了炭化温度对沙蒿生物炭形貌特征、表面官能团种类、产率变化和有机组分含量的影响。结果表明:生物炭孔径随着炭化温度的升高而增大,700℃以后生物炭结构有一定程度的破坏;生物质炭化后C–O–C、–COOH、–CH3、–CH2、–OH和C=O逐渐消失;生物炭产率随着炭化温度的升高而降低,尤其是从300℃升高至400℃产率降低最为明显,这与纤维素及半纤维素的分解有直接关系;生物炭中有机组分的C元素含量增加,由701.7 g/kg增加到899.3 g/kg,增加了197.6 g/kg;而H、O和N元素含量则逐渐降低,分别降低了21.4、171.8和6.6 g/kg;生物炭中有机组分的原子比H/C、O/C和(N+O)/C都逐渐减小。总之,生物质升温炭化过程中,炭化温度与生物炭孔径及有机组分的C元素含量呈正相关关系而与生物炭产率、生物炭中有机组分的H、O和N元素含量呈负相关关系,低温和中温炭化时生物炭保留原有的骨架结构,而高温时对其有一定程度的破坏作用,沙蒿生物质含有丰富的官能团,升温裂解过程中多数官能团消失,无机组分Si–O–Si得以保留,此外,生物质升温裂解是一个芳香性逐渐增强,亲水性和极性逐渐减弱的过程。     

广西青蒿资源研究现状

青蒿是我国传统中药,常用于消暑、明目、止汗等,其提取物青蒿素还可有效地治疗脑型疟疾。青蒿是一年生菊花科草本喜光植物,主要分布在海拔400m以下地区。广西青蒿资源丰富,全区40余个县市均有分布,为中国青蒿生产地的主要省份;2005年广西种植青蒿约670公顷,靖西县就达340公顷,且该地的青蒿提取物青蒿素含量可达1.2%。近年来,通过对青蒿野生资源的收集、筛选、生物学特性、组织培养、繁殖及栽培技术的深入研究,为建立稳定高产的青蒿生产提供了科学依据,促进了广西青蒿产业的发展。今后在青蒿生产过程中,实行中药材生产质量管理规范,保护其生物资源多样性,并利用现代生物技术,可确保青蒿生产达到高产、优质、安全和标准化,获得更多优质的青蒿,从而满足市场对青蒿素的需求。     

河北卢龙地区青蒿挥发性化学成分的气相色谱-质谱分析

采用同时蒸馏萃取法提取产自河北卢龙地区青蒿中的挥发油,测得青蒿挥发油含量为8.8%;并用气相色谱-质谱联用技术进行分离鉴定和计算机质谱图库检索,鉴定出了23种化学组分,占总挥发性物质总含量76.56%;应用峰面积归一化法确定了各成分的相对含量。结果表明:同时蒸馏萃取法提取的挥发油中主要含有N,N'-双(2,6-二甲基-6-亚硝基)庚-2-烯-4-酮(37.16%)、桉叶油素(11.20%)、3,3,6-三甲基-1,5-庚二烯-4-醇(4.49%)、石竹烯(4.43%)、大根香叶烯D(3.35%)等。     

天水地区药用蕲艾引种试验

为丰富天水中药材种植种类,从湖北黄冈引进蕲艾品种,以天水艾草为对照开展品种比较试验。结果表明,九尖蕲艾在生物学特征、产量、茎叶比、有效成分含量等方面表现均优于天水艾草,其平均株高为161.5 cm,平均株幅为24.8 cm,裂片数5片,叶色深绿。鲜重产量29 571.4 kg/hm2,较对照品种天水艾草增产290.6%;干重产量12 809.5 kg/hm2,较对照品种天水艾草增产273.6%。茎叶比0.86。经陇西数字本草检测中心检测,九尖蕲艾桉油精含量3.39 mg/g、龙脑1.12 mg/g、总灰分102 g/kg、酸不溶性灰分19 g/kg ;其中主要成分桉油精、龙脑含量均超过《中国药典》桉油精不得少于0.50 mg/g 、龙脑不得少于0.20 mg/g 的标准。九尖蕲艾植株高大、茎叶比小、产量高、药效成分高,适宜于天水地区种植。     

艾蒿提取物及其不同柱层析馏分对甜菜夜蛾产卵行为的影响

利用Syntech触角电位仪,测定了甜菜夜蛾雌成虫对艾蒿提取物和4种溶剂(苯、乙酸乙酯、丙酮和乙醇)柱层析馏分的触角反应;利用涂纸法,测定了艾蒿提取物和4种馏分对甜菜夜蛾产卵的忌避特性和抑制特性。结果表明:甜菜夜蛾雌成虫对相同浓度(10 mg/mL)提取物和馏分的触角反应存在很大差异,对丙酮馏分的反应最强烈,电位值为9.632±1.054 mV,其次为乙酸乙酯和苯馏分,以乙醇馏分的反应最弱。提取物和不同馏分对甜菜夜蛾的产卵忌避作用存在很大差异,丙酮馏分、乙酸乙酯馏分和提取物都具有一定的忌避作用,而且随浓度上升而增强,其中以丙酮馏分的忌避作用最强,10 mg/mL的忌避率达到49.0%。不同浓度处理时,都以丙酮馏分和乙酸乙酯馏分的产卵抑制作用最强,且随浓度上升而增强,10 mg/mL的抑制率分别达到72.16%和68.95%;较高浓度(5 mg/mL和10 mg/mL)时,提取物、苯馏分和乙醇馏分也具有一定的产卵抑制作用。