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Two new homothallic species ofPichia, associated with exudates ofPopulus trichocarpa andSalix sp. have been described.Pichia trehalophila sp.n. was isolated from slime exudates in two widely separatedPopulus trichocarpa trees andPichia salictaria sp.n. was isolated from two exudates ofSalix sp. The latter species was previously present as an unidentified strain ofPichia in the culture collection of the Centraalbureau voor Schimmelcultures and had been isolated from a patient in Germany. The natural habitat ofP. salictaria is considered to be in association with willow trees.  相似文献   

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Examples of beetle pollination in the South American tropics are given. The case histories refer to representatives of the families Cyclanthaceae, Annonaceae, and Araceae. In most cases the cantharophilous syndrome does not seem to be the result of coevolution but of a one-sided adaptation of flowers to the behavior, necessities, and sense-capacities of beetle species. It is emphasized that cantharophily may not necessarily be an indication of ancientness of a flower/insect relationship. Besides primitive angiosperms, there are derived and modern groups which, in their pollination, are specialized for beetles. Carludovica palmata (Cyclanthaceae) is pollinated by small curculionids which are attracted by odors in the early morning hours. Annona coriacea (Annonaceae) and Philodendron selloum (Araceae) are pollinated by large dynastid scarab beetles in the evening hours. In all three species thermogenesis occurs. Although belonging to widely separate systematic groups, Annona flowers and Philodendron inflorescences have a similar pollination biology, which indicates that their adaptations to beetles are the result of convergent evolutionary developments.  相似文献   

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In the course of attempts to isolate and characterize the ‘nesting’ or aggregation pheromone of the American cockroach, Periplaneta americana, two metabolites of tryptophane have been identified. These are oxindole and hydrocarbostyril. That these were indeed tryptophane metabolites was demonstrated by administering radiolabelled tryptophane to cockroaches following tetracycline treatment and isolating the radioactive metabolites.  相似文献   

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Stryphnodendron moricolor (Mimosaceae) is described, illustrated and discussed. The genusMonopteryx (Fabaceae) is reported for the first time outside Amazonian Brazil and adjacent Venezuela. A key distinguishing the three known species ofMonopteryx is presented.  相似文献   

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Industrial utilization of the vast wild vegetable resources of Latin America involves much more than the solution of technological problems. More difficult, at times, are the problems of labor, politics, transportation, native apathy and climate.  相似文献   

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研究小花杜鹃(Rhododendron minutiflorum)的化学成分及其α-葡萄糖苷酶抑制活性。采用正相硅胶、ODS、Sephadex LH-20和HPLC等多种色谱技术,从小花杜鹃的95%乙醇提取物中分离得到9个化合物,通过波谱分析和文献数据对比,鉴定其结构分别为rhodominutinan A(1)、rhodominutinan B(2)、3,4-di(4-hydroxy-3-methoxybenzyl)tetrahydrofuran(3)、venkatasin(4)、苔色酸甲酯(5)、苔黑酚羧酸乙酯(6)、2,4-二羟基-3,6-二甲基苯甲酸甲酯(7)、芹菜素(8)、山奈酚(9)。其中化合物1和2为新的木脂素,化合物3~9为首次从小花杜鹃中分离得到。通过α-葡萄糖苷酶抑制剂体外筛选模型评价化合物的潜在降血糖活性,结果表明化合物8和9具有较好的α-葡萄糖苷酶抑制活性,IC50值分别为57.51±6.35、54.70±3.67μM。  相似文献   

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Mauria membranifolia sp. nov. and Tapirira guianensis Aubl. ssp. subandina ssp. nov are described.  相似文献   

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Bucephalandra gigantea Bogner, spec nova, is characterized by its large habit, the relatively small inflorescences and the very slender thecae.Hottarum kinabaluense Bogner, spec nova, is differentiated by its ellipsoid ovaries, the smooth petioles and the absence of staminodes.  相似文献   

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《Journal of bryology》2013,35(4):695-699
Abstract

Weissia brachypoma sp. nov. and Ephemerum pemzinutum sp. nov. are described from western Tanzania.  相似文献   

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Compsoneura lapidißora is described as a new species. It differs from other species of Compsoneura in having dendritic hairs with articulated, flat branches, and many more (19–22 vs. up to 14) secondary veins in the leaves; it also has bracteoles which are otherwise not known in the genus and hairs on the inner surface of the perianth that surround the base of the androecium, a character unknown in other Neotropical Myristicaceae. Otoba cyclobasis is also described as a new species. It is related to Otoba acuminata with which it shares the apparently derived feature of having a swollen ring that surrounds the filament column, but O. acuminata differs from O. cyclobasis in having fewer secondary veins (5–9 vs. 14–17), and a bottleshaped (not slender) filament column.  相似文献   

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Two new species of Marasmiellus (Tricholomataceae, Agaricales) are described and illustrated from Japan: (1) Marasmiellus crassitunicatus sp. nov. (subsection Inodermini of section Marasmiellus) forms dark reddish-brown, orbicular to reniform basidiomata constantly accompanied by tufts of short filiform rhizomorphs, growing on the bark of living coniferous or broad-leaved trees; and (2) Marasmiellus vernalis sp. nov. (subsection Quercini of section Dealbati) forms small brown basidiomata with nondiverticulate pileipellis elements, growing on the bark of living Pinus thunbergii in spring (April to June).  相似文献   

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Two species ofMenziesia, M. katsumatae andM. yakushimensis, are described as new to science. The former is characterized by having a long axis of the inflorescence with 15–20 bracts while the other species has a short axis with about ten bracts.M. katsumatae is restricted to the Hakusan range extending northward to Mt. Hōdatsuzan in the Noto Peninsula.M. yakushimensis has been considered asM. purpurea Maxim. in Kyūshū, but it is clearly distinguishable from the latter by the color and shape of the corolla and the presence of fasciculate glandular-hairs at the base of the corolla lobes. It is endemic to the higher altitudes of Yaku-shima Island, Kagoshima Prefecture.  相似文献   

19.
Shen YC  Prakash CV  Chang YT 《Steroids》2001,66(9):721-725
Two new polyhydroxysteroids isihippurols A (1) and B (2) were isolated from the MeOH extract of the gorgonian Isis hippuris in addition to nine known steroids namely gorgosterol, 3alpha-acetoxy-24-methyl 11beta,18; 18,20beta; 22,25-triepoxy-5alpha-furostane, hippurin-1, 22-epi-hippuristanol, 22-epi-hippurin-1, 3-acetyl-2-deacetyl-22-epi-hippurin-1, 2-deacetylhippurin-1, 3beta, 7alpha, 11alpha-trihydroxygorgost-5-ene-12beta-acetate and 2-deacetyl-22-epi-hippurin-1. The structures of 1 and 2 have been determined as 1alpha, 3beta, 5alpha, 6beta, 11alpha-pentahydroxygorgosta-12beta-monoacetate and 1alpha, 3beta, 11alpha-trihydroxygorgosta-5alpha, 6alpha-epoxy-12beta-monoacetate respectively by spectral analysis and chemical correlation.  相似文献   

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1 彭州岩乌头 新变种 图1图1 彭州岩乌头Fig.1 AconitumracemulosumFranchvar.pengzhouenseW.J.ZhangetG.H.ChenAconitumracemulosumFranch.var.pengzhouenseW.J.ZhangetG.H.Chen,var.nov.Fig.1A.rhombifoliumChenvar.pengzhouenseW.J.ChangetG.H.CheninWestChinaJourn.Pharm.Scien.10(1):54,fig.2.1995,nom.nud.A…  相似文献   

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