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1.
Fuel oils from euphorbs and other plants 总被引:3,自引:0,他引:3
MELVIN CALVIN 《Botanical journal of the Linnean Society. Linnean Society of London》1987,94(1-2):97-110
Fuel oils from Euphorbs and other plants. The increasing energy costs of finding petroleum, together with the sure knowledge that its supply is finite, has prompted us to seek other sources of liquid hydrocarbon for both fuel and material. We have turned to annually renewable plant sources such as seed oils, an obvious source, with palm oil as the most productive. Sugar cane used to produce ethanol is another fuel source already in use.
We have examined non-food plants which can be grown on marginal soil for their productivity, particularly the genus Euphorbia. All species of this genus produce a latex which can be converted into useful fuel and other material, including precursors for what might be a valuable anti-tumor agent. Euphorbias and other similar plants require repeated planting and harvesting of the entire plant, which constitutes a drain on the soil. Trees can be long-term sources for hydrocarbon-like materials with a single planting. Examples are: the genus Copaifera which can be tapped for sesquiterpenes, the genus Pittosporum which bears fruits rich in terpenes and can be harvested annually. Finally, there are algae whose oil productivity is already of interest.
It seems possible to modify genetically the terpene biosynthetic pathways in plants to improve both the quality and quantity of the oils produced from them. 相似文献
We have examined non-food plants which can be grown on marginal soil for their productivity, particularly the genus Euphorbia. All species of this genus produce a latex which can be converted into useful fuel and other material, including precursors for what might be a valuable anti-tumor agent. Euphorbias and other similar plants require repeated planting and harvesting of the entire plant, which constitutes a drain on the soil. Trees can be long-term sources for hydrocarbon-like materials with a single planting. Examples are: the genus Copaifera which can be tapped for sesquiterpenes, the genus Pittosporum which bears fruits rich in terpenes and can be harvested annually. Finally, there are algae whose oil productivity is already of interest.
It seems possible to modify genetically the terpene biosynthetic pathways in plants to improve both the quality and quantity of the oils produced from them. 相似文献
2.
以内质多刺植物霸王鞭(Euphorbia royleana)和仙人掌(Opuntia monacantha)为特征的具有荒漠植被景观的元江干热河谷肉质多刺灌丛是一种特殊的次生植被,是在近代原生植被的强烈破坏下,栽培逸生的霸王鞭和仙人掌在局部特别千热土薄多石之处发展而形成的。该群落外貌和结构特殊,可初步定为一个群丛,下分两个亚群丛。在种类组成上,该群落与热带亚洲干早植物区系联系密切,在区系起源上具有古南大陆残余背景,在群落形成和发展上又与人为活动相联系。 相似文献
3.
Bruno Mies Maria Soledad Jiménez Domingo Morales 《Plant Systematics and Evolution》1996,202(1-2):27-36
The leafless spurgeEuphorbia aphylla (Euphorbiaceae), an endemic species restricted to several of the Canary Islands where it inhabits coastal and arid localities, expresses Crassulacean Acid Metabolism (CAM) when it is subjected to summer drought. A flexible CAM is consistent with the general ecology of the species. It is the only member of sect.Tirucalli native to the Canary Islands and is at the north-western edge of the section's biogeographical range. The other members of the section have a paleotropic distribution and are found throughout Africa. Many of them are regarded as obligate CAM plants, includingE. tirucalli which was used as a comparison in ecophysiological experiments examining the response ofE. aphylla to drought and temperature. 相似文献
4.
Xiong Zhang Ming-You Peng En-Ming Feng Qing-Dan Li Lu Chen Hu-Cheng Yang Bing Guo Hong Liang Ying-Tong Di Lei Tang Ying Yan 《化学与生物多样性》2023,20(10):e202301061
Three previously undescribed diterpenoids, helioscopnoids A–C, and eight known compounds were isolated from the whole plants of Euphorbia helioscopia. Their structures were established by extensive analysis of spectra and data comparison with previous literatures. Among them, compound 4 was identified as 24,24-dimethoxy-25,26,27-trinoreuphan-3β-ol with revised configurations of C-13, C-14, and C-17 (13R*, 14R*, 17R*). Cytotoxicity assays revealed that all compounds exhibited varying levels of cytotoxicity against H1975 cells, with compound 9 displaying the most potent activity, as indicated by cell viability rates of 18.13 % and 20.76 % at concentrations of 20 μM and 5 μM, respectively. This study expands the understanding of E. helioscopia terpenoids’ structural diversity and biological activities, contributing to the exploration of potential therapeutic applications. 相似文献
5.
甘遂块根的发育解剖学研究 总被引:7,自引:3,他引:4
甘遂根在发生次生生长后,局部区域的木栓形成层向内产生多层栓内层细胞,这些细胞不断扩大,使这一区域的根发生膨大。以后维管形成层开始活路,产生薄壁组织化的次生维管组织,同时栓内层继续增加,从面形成了块根。由次生木质部中胶质纤维形成的薄壁组织细胞也参与了块根的后在。块根的这种形成方式应为一种异常生长。块根发育过程中,各种薄壁组织中淀粉粒的数目及体积不增加,甘遂根中的乳汁管为无节,分枝和多核的,不具淀粉粒 相似文献
6.
Y. Yamamoto R. Mizuguchi Y. Yamada 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1982,61(2):113-116
Summary A high pigment-producing strain of cultured Euphorbia millii cells was isolated by clonal selection. The pigment obtained was red and consisted mainly of anthocyanin. The amount of this pigment obtained after 24 selections was seven times that found in the original cells. Statistical and cell-pedigree analyses proved that this cell strain has stable productivity for this red pigment. 相似文献
7.
山东10种植物的核型分析 总被引:5,自引:1,他引:5
对山东10 种植物进行了核型分析。茴茴蒜( Ranunculuschinensis Bge-) 染色体数目2n =16 , 核型公式K(2n) = 2x = 16 = 2 M + 2m + 2sm + 10st, “3A”类型; 五脉地椒( Thymusquinquecostatus Celak-) 染色体数目2n= 26 , 核型公式K (2n) = 2x= 26 = 8 M + 18m , “1A”类型; 蛇床( Cnidium monnieri(L-) Cuss-) 染色体数目2n= 20 , 核型公式K (2n) = 2x= 20 = 2M+ 16m + 2sm , “2B”类型; 波斯菊( Cosmos bipinnatus Cav-) 染色体数目2n = 24 , 核型公式K(2n) = 2x = 24 = 16m + 2m (sat) + 6sm , “2A”类型; 白车轴草( Trifolium repens L-) 染色体数目2n= 32 , 核型公式K (2n) = 4x = 32 = 32m , “1A”类型; 铁苋菜( Acalypha australis L-)染色体数目2n = 32 , 核型公式K (2n) = 2x= 32 = 32m , “1B”类型; 地构叶( Speranskia t? 相似文献
8.
泽漆营养器官发育解剖学研究 总被引:1,自引:0,他引:1
采用石蜡切片法、半薄切片法对泽漆营养器官的发育过程进行了观察,同时对3种器官中乳汁管的分布和大小进行了分析。结果表明:泽漆根的发育类似于草本双子叶植物根的一般发育规律。初生木质部为三原型。茎的初生结构由表皮、皮层、维管束环和髓构成,其髓中有空腔,而茎的次生生长过程中维管形成层的活动短暂,仅产生少量次生维管组织,不形成周皮。叶的发育包括原分生组织、初生分生组织和成熟结构3个阶段,属于异面叶结构。泽漆乳汁管主要分布在维管束韧皮部的外侧。在3种器官中,乳汁管直径差异较大,依次为根>茎>叶。 相似文献
9.
京大戟是多年生草本药用植物,入药部分是其干燥根,但可入药的京大戟资源由于生长缓慢以及环境污染的加剧而越发匮乏,因此解决大戟资源日益紧张的问题是当今药用植物资源开发与利用方向的重要课题。京大戟含有三萜类、二萜类、黄酮类等丰富的活性成分,一些常见药用植物的有效成分是三萜类化合物,其在抗病毒、抗肿瘤、免疫调节等方面具有很好的活性。对植物萜类物质代谢起重要作用的关键酶,如3-羟基,3-甲基戊二酰辅酶A还原酶(hmgr)、鲨烯合酶(sqs)、法尼基焦磷酸合酶(fps)的基因克隆及活性研究取得了进展和突破,但通过调控萜类物质代谢途径中关键酶基因的表达来诱导终产物合成的研究鲜有报道。通过研究大戟萜类物质代谢途径进而利用基因工程手段提升目的物质的产量来解决京大戟药源短缺问题具有重要意义。该研究以大戟愈伤组织为材料,使用茉莉酸甲酯分别按时间梯度和浓度梯度进行诱导,将诱导后的愈伤组织分为两部分:一部分提取其总RNA,以actin为内参基因进行反转录,实时定量RT-PCR分析大戟三萜类代谢途径中hmgr、sqs与fps基因的相对表达差异;另一部分用于提取其总三萜并使用分光光度法进行含量测定。实时定量RT-PCR分析结果表明,茉莉酸甲酯可诱导3个基因的表达,但其表达模式不一样。相应的京大戟愈伤组织中总三萜的含量明显提高,最高可较未处理样品增加27%。研究结果可为茉莉酸甲酯促进药用植物大戟三萜类物质积累的分子机制研究提供参考。 相似文献
10.
大戟甲羟戊酸途径关键酶基因hmgr的克隆与分析 总被引:1,自引:0,他引:1
通过比较6种植物8条甲羟戊酸途径关键酶3-羟基-3-甲基戊二酰辅酶A还原酶(HMGR)基因同源区域,设计简并引物,利用RT-PCR技术成功地从大戟(Euphorbia pekinensis)叶中扩增出458bp的基因片段。通过BlastP比较,所推断的大戟HMGR蛋白序列与杜仲Eucommia ulmoides(AAV54051)、穿心莲Andrographis paniculata(AAP14352)、胡黄连Picrorhiza kurrooa(ABC74565)、橡胶树Hevea brasiliensis(AAU08214)、海岛棉Gossypium barba-dense(ABC71314)、龙胆草Gentiana lutea(BAE92730)的一致性分别达到90%、86%、86%、92%、87%和88%。蛋白质保守区、特征区以及进化树分析,初步证实该基因为hmgr基因,这是首次报道从药用植物大戟中克隆到甲羟戊酸途径关键酶HMGR的基因片段。 相似文献