超临界CO2萃取红景天中红景天苷、苷元酪醇的研究

采用超临界CO₂ 萃取法和乙醇常温浸提法相比较, 研究从红景天中提取红景天苷、苷元酪醇的工艺条件, 结论是:采用超临界CO₂ 萃取法能萃取出红景天生药中红景天苷的1.2%, 提取率不高, 但该方法能萃取出80%的苷元酪醇, 萃取液中苷元酪醇的相对含量可达45.68%;乙醇常温浸提法能将红景天苷、苷元酪醇同时有效萃取, 且得率较高, 但是萃取液中两物质相对含量较低, 进一步分离纯化将有难度。本研究结果表明, 将超临界CO₂ 萃取法和乙醇常温浸提法有效结合, 可实现两物质的有效分离, 推进红景天有效成分的产业化进程。     

Turkana Basin-Middle Awash Valley correlations and the age of the Sagantole and Hadar Formations

The Moiti, Lomogol and Wargolo Tuffs of the Turkana Basin correlate with similar layers in the Sagantole Formation exposed in the Middle Awash Valley, Ethiopia. These correlations demonstrate that the tephrostratigraphy of the Turkana Basin can be applied to the Middle Awash Valley. Consideration of our analyses together with previous analyses shows that more volcanic ash layers are present in the Sagantole Formation than have been reported and also that the proposed correlation of VT-2 between Bodo and Belohdelie is incorrect. In addition, the correlations suggest that the age of the Cindery Tuff of the Sagntole Formation is about 3·8 Ma, at the young end of the range proposed earlier (3·8–4·0 Ma). This implies that the hominid skull fragments from the Sagantole Formation are 3·8–3·9 Ma. The upper part of the Sagantole Formation contains the Lomogol Tuff (ca. 3·6 Ma). Because the Sagantole Formation underlies the Hadar Formation, the base of the Hadar Formation can be no older than 3·8 Ma and is probably younger than 3·6 Ma, in agreement with correlation of the Tulu Bor (ca. 3·35 Ma) and Sidi Hakoma Tuffs. As all hominid fossils presently known from the Hadar Formation are younger than the Sidi Hakoma Tuff, they must be younger than 3·35 Ma. This estimate agrees with faunal evidence from the lower part of the Hadar Formation, and allows placement of hominids from Laetoli, the Middle Awash Valley and the Turkana Basin in temporal order.     

高山红景天对肝纤维化大鼠PDGF-BB mRNA表达的影响

目的:观察单方生药高山红景天对实验性肝纤维化大鼠的疗效,探讨其可能的作用机制。方法:将实验动物随机分为正常对照组(A)、模型组(B)、秋水仙碱组(C)、红景天高剂量组(D)、红景天低剂量组(E)。除正常对照组外,其余4组均用四氯化碳诱发肝纤维化。各组于造模第8周末处死动物,分别用放射免疫法检测血清层粘连蛋白(LN)、Ⅲ型前胶原(PCⅢ)、透明质酸(HA)及Ⅳ型胶原(CⅣ);RT-PCR检测肝组织PDGF-BB mRNA的表达。结果:与模型组大鼠比较,经该中药治疗,大鼠血清中LN、PCⅢ、HA、CⅣ水平明显降低(P<0.01);大鼠肝组织内PDGF-BBmRNA表达明显下降(P<0.01);大鼠肝组织病理学检测改善显著。结论:单方生药高山红景天能有效地抑制肝纤维化的发展,其机制可能是通过下调肝组织内PDGF-BB mRNA表达,降低ECM的分泌而达到的。     

红景天苷对运动后自由基和能量代谢改变的影响

目的:探讨红景天苷在运动过程中对自由基和能量代谢相关指标的作用,从抗氧化系统、能量代谢系统等方面研究红景天苷抗运动性疲劳的机制。方法:本研究采用小鼠运动模型,40只雄性小鼠随机取分为4组(n=10):红景天苷运动组,红景天苷安静组,运动对照组,安静对照组。红景天苷运动组和安静组两组以150 mg/(kg.d)的红景天苷灌胃给药,运动和安静对照组两组以同样体积蒸馏水灌胃,连续给药2周;末次灌胃30 min后,运动组进行无负重游泳120 min,然后测定与运动性疲劳相关的生化指标。结果:研究结果表明,红景天苷能够提高运动小鼠肝脏内超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)等抗氧化酶活性,降低丙二醛(MDA)含量;红景天苷具有稳定运动小鼠血糖,增加肝、肌糖原储备,防止长时间运动后血糖和肝、肌糖原水平降低的作用;红景天苷可提高运动小鼠血浆总胆固醇(TC)、甘油三酯(TG)及游离脂肪酸(FFA)的水平,有影响不同状态下的脂肪代谢,促进脂肪利用的作用。结论:红景天苷对运动过程中自由基和能量代谢改变的影响是其抗运动性疲劳的机制之一。     

高山红景天营养器官解剖学的研究

利用光学显微镜和扫描电镜对高山红景天营养器官进行了详细观察 ,结果表明 :高山红景天营养器官结构与双子叶多年生草本植物解剖结构相似。其地下部分的根茎和根较发达。营养器官储藏物质分布有一定规律 ,其含量依次为根茎 >根 >茎>叶 ,这与药用部位相吻合。并对高山红景天生存环境与其结构相关性进行了讨论     

高山红景天细胞悬浮培养中红景天甙生物合成代谢调控Ⅱ:真菌诱导物的影响

考察了6种真菌诱导物对高山红景天(Rhodiola sachalinensis A. Bor)细胞生长与红景天甙积累的影响。其中以黑曲霉诱导物效果最好。在细胞培养初期添加浓度为10mg(carbohydrate)/L的黑曲霉诱导物能使培养细胞中红景天甙含量提高到0.995％。前体与诱导物调控组合运用最终使红景天甙产量达到167.4mg/L,是对照培养的3.5倍。另外,对真菌诱导物的作用机理也进行了探讨,真菌诱导物添加促进红景天甙的积累应该与激活培养细胞中的苯丙烷类代谢途径有关。     

高山红景天细胞悬浮培养中红景天甙生物合成代谢的调控 Ⅰ:前体的影响

探索了高山红景天(Rhodiola sachalinensis A.Bor)细胞培养中红景天甙生物合成的途径,认为甙元酪醇是经由莽草酸途径生成的。在此基础上研究了酪醇、L-酪氨酸与L-苯丙氨酸三种前体加入对红景天甙生物合成的调控作用。结果表明,酪醇、酪氨酸等前体易被多酚氧化酶氧化成褐色,用与前体浓度为1:1的V。来防止褐化效果显著;浓度为0.5mmol/L的酪醇,酪氨酸及苯丙氨酸在细胞培养15d时添加,使红景天甙含量由0.336％分别提高到1.43％、1.11％、0.85％。     

Living on the Edge: Attitudes of Rural Communities toward Bengal Tigers (Panthera tigris) in Central India

To date, most studies of the Bengal tiger (Panthera tigris) are of biological research, techniques, conservation, population modeling, or tiger– human conflicts. Few studies have attempted to understand the rural population that share a region with the tigers, and some of the villages are even displaced in the name of conservation. Hence, we undertook a survey of 10 villages that are located in the buffer zone of the Bor Tiger Reserve (BTR). Most of the villagers interviewed had encountered tigers, most considered them a boon and beneficial to their livelihood, and almost all displayed environmental awareness and stressed the necessity to conserve tigers in order to ensure their own continued survival. Some stressed the religious connotation and significance because the tiger is the animal of transport of the Goddess Durga. A minority expressed a negative attitude that resulted not from damages incurred by the tigers, but from discontent following inept handling of property losses by the authorities, who did not provide compensation in time, or paid only a small part of the original value of the loss. We conclude that in order to ensure the continued goodwill of the local stakeholders, it is important that the state and national governments react in a timely manner and ensure that the farmer is compensated in full. Support of the villagers who cohabit with tigers will ensure the continued survival of the two entities.     

滇西香茅挥发油的化学成分

滇西香茅(Cymbopogon khasiamus(Hack.)Stapf ex Bor)为禾本科植物,分布于印度及缅甸,该植物过去在中国无分布记载,作者在云南首次发现。其挥发油为主要有效成分,当地与芸香草(Cymbopogon distans(Steud)Wats.)混用。为合理开发和利用该种植物,对挥发油的化学成分进行了分析。     

高山红景天愈伤颗粒组织悬浮培养动力学及工艺的研究

研究了高山红景天愈伤组织颗粒悬浮培养过程的生长及红景天甙合成的规律,发现红景天甙合成与细胞生长偶联,两者之间的关系表示为q=5．38×10^-3μ。其产率系数Yx/s及维持系数m分别为0．66g·g^-1和0．033g·(g·d)^-1。在3.5L气升式反应器中研究了培养过程的操作特性,发现“发泡”现象几乎不存在,氧传递系数K1a的变化不同常规植物细胞的悬浮培养．愈伤组织颗粒在培养过程中经历一个由小变大,后叉变小的过程。