致命鹅膏菌毒素对DMBA/巴豆油诱导小鼠皮肤肿瘤的治疗作用

研究了致命鹅膏中的毒素在安全剂量下抑制小鼠皮肤肿瘤的效果,并对此毒素的药用安全性进行初步评价。采用经典的DMBA/巴豆油诱导小鼠皮肤乳头状瘤形成的二阶段致癌模型,观察和评价致命鹅膏毒素在不同剂量下抑制肿瘤的效果,并且通过测定血清中氨基己糖的含量来判断对肝损伤的情况。结果表明,致命鹅膏毒素在某一低剂量下对DMBA/巴豆油诱导小鼠皮肤乳头状瘤有较好的治愈效果,且对小鼠肝脏无损伤,证明了致命鹅膏毒素可以较好地治疗皮肤癌。     

气升式液体培养假褐云斑鹅膏菌丝及毒素检测分析

采集并组织分离到假褐云斑鹅膏Amanita pseudoporphyria的纯培养菌丝。培养发现其在琼脂培养基上生长形态与一般蕈菌有差别。摇瓶液体培养条件下,假褐云斑鹅膏菌丝体干重为0.626g/L,在气升式反应器内假褐云斑鹅膏菌丝体干重可达到1.629g/L。反应器培养的菌丝体毒素的HPLC分析表明菌丝体内含有鹅膏毒肽,而不含有鬼笔毒肽。结果表明可以通过液体培养鹅膏菌丝体来生产鹅膏毒素。     

二羟鬼笔毒肽(PHD)的制备及其毒理研究

利用反相高效液相色谱技术从灰花纹鹅膏菌Amanitafuliginea中分离纯化出二羟鬼笔毒肽(PHD),纯度达到98%。毒理表明二羟鬼笔毒肽(PHD)能引起植物细胞坏死,对小白鼠的半致死量(LD₅₀)为2mg/kg。     

Population genetic structure of an ectomycorrhizal fungus Amanita manginiana in a subtropical forest over two years

The population genetic structure of the late-stage fungus Amanita manginiana in a natural forest in Dujiangyan, southwest China was examined over two years using inter-simple sequence repeat (ISSR) markers. Seven ISSR primers were used and 170 bands were obtained in this population: 134/160 and 135/153 bands were polymorphic for sporocarps of 2001 and 2002, respectively. Each sporocarp represented a single genet in 2001 and 2002, and no identical genets were found between the two years. The results of genetic similarity comparison, using unweighted pair group method with arithmetic means, and analysis of molecular variance, indicated that although genetic variances were mainly within individuals of the same year the genetic variance between years was statistically significant (P<0.001). Relationships between genetic similarity and spatial distance of pairwise sporocarps were also found to be different in the two years. The differences in genetic structure and genetic similarity between individuals of the two years implied that the sporocarps were not likely to be derived from continuous generations, i.e., the sporocarps collected in 2002 were not developed from sexual spores dispersed by sporocarps of 2001. We suggest that the life-cycle traits of ectomycorrhizal (ECM) fungi should be considered in genetic studies on ECM fungal populations.     

Small genets of Lactarius xanthogalactus, Russula cremoricolor and Amanita francheti in late-stage ectomycorrhizal successions

We determined the size of genets of late-stage ectomycorrhizal fungi in field sites in coastal Northern California. Basidiocarps were collected, mapped and subjected to genetic fingerprinting using amplified fragment length polymorphisms (AFLPs). The minimum size estimates for the largest genets of Amanita francheti, Lactarius xanthogalactus and Russula cremoricolor were 1.5, 9.3 and 1.1 m2, respectively. The molecular markers also showed that R. cremoricolor is dimorphic, with red- and white-capped morphotypes of this species forming a continuous population. Our results suggest that spore propagation plays a much more important role in the life history of the Russulaceae in undisturbed forest settings than previously recognized. Fungi appearing late in the succession sequence and systems without obvious disturbance therefore do not necessarily colonize primarily by mycelium.     

Vanadium in biology—the case of the Amanita toadstools

Abstract

The studies relative to the presence, state and combined form of vanadium in Amanita toadstools are reviewed critically. A possible role for the vanadium containing compound “amavadine” is suggested on the basis of the present knowledge of its structure, thermodynamic stability and oxidation-reduction behaviour.     

红黄鹅膏子实体不同极性部位及粗多糖对B16细胞活力的影响

为探讨红黄鹅膏子实体不同极性部位和粗多糖对鼠黑色素瘤细胞B16活力的影响,采用MTT法检测红黄鹅膏子实体醇提物石油醚、乙酸乙酯、正丁醇萃取部位和水层及水提醇沉得到的粗多糖对B16细胞的抑制活性。结果表明:红黄鹅膏子实体不同极性部位及粗多糖(100⁴00 mg/mL)处理24 h后,其石油醚部位、乙酸乙酯部位和子实体粗多糖对B16细胞活力有明显的抑制作用。红黄鹅膏子实体不同极性部位和粗多糖在一定时间内对B16细胞活力的抑制呈浓度依赖性。     

我国鹅膏菌新发现种--致命鹅膏(Amanita exitialis)的肽类毒素分析

采用高效液相色谱(HPLC)技术对在广州发现的鹅膏菌新种——致命鹅膏(Amanita exitialis)不同组织部位的肽类毒素(鹅膏毒肽和鬼笔毒肽)的含量进行了分析,结果表明,致命鹅膏是一种剧毒蘑菇,其毒素含量相当高,子实体中组织部位不同,毒素含量以及鹅膏毒肽和鬼笔毒肽在其中的分布也不一样,菌盖中的毒素含量最高,达8152．6μg／g干重,菌柄的毒素含量次之,为3742．3μg／g干重,菌托中的毒素含量最低,只有1142．5μg／g干重;在菌盖、菌柄和菌托中都以鹅膏毒肽为主,尤其以α-amanitin的相对含量最高,但从菌盖至菌柄到菌托,鬼笔毒肽尤其是Phallacidin的相对含量依次增加。     

灰花纹鹅膏中三个鹅膏毒肽的分离和结构研究

从灰花纹鹅膏(Amanita fuliginea)中分离得到3个已知鹅膏毒肽类成分,利用波谱方法(^1H-NMR、^13C-NMR、2D-NMR和FAB-MS等)对这些结构较为复杂的环肽类成分进行了鉴定,结构分别为α-Amanitin、β-Amanitin和Amanin。     

块磷鹅膏的培养条件及所产Amanitins毒素的分析

采集并组织分离到块磷鹅膏Amanita spissa的纯培养菌丝。探讨了各种培养条件对块磷鹅膏菌丝生长的影响,实验结果表明,在28℃,pH 6.0,避光的条件下块磷鹅膏的菌丝体生长最好。液体反应器人工培养块磷鹅膏获得成功,其液体培养的菌丝体干重在摇瓶中为0.893g/L,在气升式反应器内可达到2.33g/L。固体斜面培养和气升式反应器液体培养的菌丝体的HPLC分析表明菌丝体内含有鹅膏毒肽,而不含有鬼笔毒肽。两种培养条件下菌丝体的-αamanitin毒素含量略有不同,固体斜面菌丝体为26.02μg/gDCW、反应器培养菌丝体为15.25μg/gDCW。通过抑芽法试验也证明固体和液体培养菌丝体中含有-αamanitin,且具有和子实体中-αamanitin相同的生物学活性。结果表明有可能通过液体大规模培养鹅膏菌丝体来生产鹅膏毒素。