Supercritical carbon dioxide extraction of colchicine and related alkaloids from seeds of Colchicum autumnale L

A method for the extraction of the alkaloids colchicine, 3-demethylcolchicine and colchicoside from seeds of Colchicum autumnale by supercritical carbon dioxide has been established. Several parameters such as pressure, temperature, percentage of modifier and extraction time have been examined. Two extraction steps with constant carbon dioxide density (0.90 g/mL) and flux (1.5 mL/min) were required to extract the alkaloids in 110 min using 3% methanol as modifier. The quantitative determination of the alkaloids was performed by HPLC; the percentages of recovery were higher than 98% for the three alkaloids. This extraction procedure was compared with a conventional method involving maceration and sonication, and the same levels of alkaloids were obtained in each case. The supercritical carbon dioxide method is, however, very efficient, more rapid and more environmentally friendly than conventional methods.     

FINE STRUCTURE OF A TERRESTRIAL CYANOBACTERIAL MAT FROM ANTARCTICA1

The fine structure of a cyanobacterial mat collected from the fellfield ecosystems of Signy Island, Antarctica, was examined using some novel light and scanning electron microscope techniques. The mat was up to 5 mm thick and was distinctly layered. The surface of the mat consisted of nonliving material above a zone of Phormidium autumnale (Ag.) Gom. filaments. We suggest that the surface layer protects the cyanobacterium from the effects of desiccation or high irradiance. Lower layers were less structured than the upper layer and included other taxa of cynobacteria and eukaryotic algae, although still dominated by Phormidium. The lowest layers consisted of dead organic material. The mat bound large amounts of inorganic material within and between the subsurface layers.     

秋水仙花生物碱

从云南昭通引种欧洲秋水仙花中分离出6个生物碱:秋水仙碱(Ⅰ),2-去甲秋水仙碱(Ⅱ),2-去甲脱羰秋水仙碱(Ⅲ),2-去甲-17-羟基秋水仙碱(Ⅳ),2-去甲-β-光秋水仙碱(Ⅴ),β-光秋水仙碱(Ⅵ)。     

Clogging of groundwater recharge basins by cyanobacterial mats

Abstract Cyanobacterial mats, which develop on the surface of groundwater recharge basins in the Dan Region Wastewater Reclamation Project in Israel, tend to reduce the rate of effluent infiltration into the ground. The purpose of this work was to study the cyanobacterial populations found in the basins and to elucidate their contribution to the clogging process.
Three cyanobacterial types were isolated and their clogging capacity was determined in a simulation system. Simulation experiments were also used to study the effects of various flooding regimes on mat development and permeability.
In the recharge basins, clogging events have occurred in the autumn, winter or spring. During these seasons, Phormidium autumnale was found to be one of the dominant cyanobacterial types in the mat. This organism is capable of rapid gliding, forms raft-like structures, produces an extracellular sheath, and secretes copious amounts of mucus. The remarkable clogging capacity of P. autumnale is thought to be related to these features. Another cyanobacterium, which predominates in the mats during the summer, does not express this combination of features and its clogging capacity is much lower.
The recharge basins are normally flooded with effluent for 24 h and dried for 48 h. In a simulation experiment clogging was enhanced when cyanobacterial mats were not allowed to dry thoroughly between floodings. Alteration of the recharge regime to 10 h of flooding during the night only, followed by 38 h of drying, enabled temporal separation of light availability and water availability. Under this regime the development of cyanobacterial mats was significantly retarded. It is concluded that night-flooding can alleviate the operational problems associated with clogging of the recharge basins by cyanobacterial mats.     

秋水仙花的化学成分Ⅱ.非生物碱成分

从云南昭通种植的秋水仙（Ｃｏｌｃｈｉｃｕｍ ａｕｔｕｍｎａｌｅ）花中分离到５个非生物碱,分别是５,７,３’,４’－四羟基黄酮,５,７,４’－三羟基黄酮,正三十一烷,正三十醇和β－谷甾醇。     

中国北部地区一些针叶树生斑痣盘菌

本文报道我国北部地区针叶树生斑痣盘菌目(Rhytismatales)真菌6属13种。其中哈尔滨散斑壳(Lophodermium harbinense Y.R.Lin)是新种,秋散斑壳(L.autumnale Darker)和雪松散斑壳(L.cedrinum Maire)为中国新记录种,其余诸种国内曾有过记录。对新种作了拉丁文、汉文描述及图解,对新记录种进行了简要记述,并记载了已知种的寄主新记录和地理新分布。