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1.
Fuel oils from euphorbs and other plants   总被引:3,自引:0,他引:3  
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   
2.
Histological observations of okra Abelomoschus esculentus ''Clemson Spineless'' and ridgeseed spurge Euphorbia glyptosperma (a common weed) infected with Meloidodera charis Hopper, indicated that the juvenile nematode penetrated the roots intercellularly. Within 5 days after plant emergence the nematode positioned its body in the cortical tissue parallel to the vascular system. By 10 days after plant emergence the juvenile had extended its head into the vascular system and initiated giant cell formation, generally in protophloem tissue. Giant cells were one celled and usually multi-nucleate. Eggs were observed in the female body 30 days after plants emerged and juveniles were found within the female body by 40 days. Nematode development progressed equally in the root system of either host plant. Generally, throughout the nematode''s life cycle its entire body remained inside the cortical tissue of okra. In ridgeseed spurge, however, the posterior portion of the female erupted through the host epidermis as early as 15 days after plant emergence; only the head and neck remained embedded in the host. The nematode caused extensive tissue disruption in the cortical and vascular system of both plant species. Corn, Zea mays, was another host of the nematode.  相似文献   
3.
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   
4.
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   
5.
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   
6.
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   
7.
月腺大戟根中乙酰基间苯三酚衍生物   总被引:6,自引:0,他引:6  
从月腺大戟(Euphorbia ebracteolata Hayata)根中分离出一种新的二苯甲烷化合物-双去甲基伪绵马素-AA和2,4-二羟基-6-甲氧基-3-甲基苯乙酮,并用光谱和化学方法确定前者的结构为3,3-二乙酰基-4,4-二甲氧基-2。25,6-四羟基二苯甲烷  相似文献   
8.
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   
9.
Euphorbia factor L3, a lathyrane diterpenoid extracted from Euphorbia lathyris, was found to display good anti‐inflammatory activity with very low cytotoxicity. To find more potent anti‐inflammatory drugs, two series of Euphorbia factor L3 derivatives with fatty and aromatic acids were designed and synthesized. Among them, lathyrane derivative 5n exhibited most potent inhibition on LPS‐induced NO production in RAW264.7 cells with no obvious cytotoxicity. To determine the key characteristics of Euphorbia factor L3 derivatives that contribute to anti‐inflammatory activity, we conducted a structure‐activity relationship study of these compounds.  相似文献   
10.
Studies of the phytotoxic effects between plants can be a crucial tool in the discovery of innovative compounds with herbicide potential. In this sense, we can highlight ruzigrass (Urochloa ruziziensis), which is traditionally used in the crop rotation system in order to reduce weed emergence. The aim of this work was to characterize the secondary metabolites of ruzigrass and to evaluate its phytotoxic effects. In total, eight compounds were isolated: friedelin, oleanolic acid, α‐amyrin, 1‐dehydrodiosgenone, sitosterol and stigmasterol glycosides, tricin and p‐coumaric acid. Phytotoxic effects of the crude methanolic extract and fractions of ruzigrass were assessed using germination rate, initial seedling growth, and biomass of Bidens pilosa, Euphorbia heterophylla and Ipomoea grandifolia. Chemometric analysis discriminated the weed species into three groups, and B. pilosa was the most affected by fractions of ruzigrass. The phytotoxic activities of 1‐dehydrodiosgenone, tricin, and p‐coumaric acid are also reported, and p‐coumaric acid and 1‐dehydrodiosgenone were active against B. pilosa.  相似文献   
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