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1.
Catherine J. Taylor Ben J. Carrick Lesley Galbraith Stephen G. Wilkinson 《FEMS microbiology letters》1993,106(1):65-69
Abstract Reference strains of ' Pseudomonas diazotrophicus ' produce a range of polar lipids atypical of authentic Pseudomonas species. In addition to the phospholipids common in Gram-negative bacteria (phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylethanolamine), N -methylated derivatives of phosphatidylethanolamine (including phosphatidylcholine) and an ornithine amide lipid are also present. The preponderant ester-bound fatty acid (up to 80% of the total) is cis -vaccenic acid ( cis -octadec-11-enoic acid), while 3-hydroxyoctadecanoic acid is the major amide-bound fatty acid in the ornithine lipid. Possible implications of the data for classification of the organism are discussed. 相似文献
2.
T. A. Jaarsma E. Lohmanns H. Hendriks T. W. J. Gadella T. M. Malingré 《Plant Systematics and Evolution》1990,169(1-2):31-39
InS. tuberosum subspp.tuberosum andnodosum, S. grandiflorum andS. ibericum the presence of the pyrrolizidine alkaloids lycopsamine, echimidine and symphytine could be demonstrated. The taxonS. tuberosum contains an unknown compound that seems to be specific for this taxon. This compound is not the pyrrolizidine alkaloid anadoline which has previously been reported for this species. It is possibly represented by a peak on GC/MS with a molecular ion peak at m/z 623 (as TMS derivative) and can be used as a chemotaxonomic marker for the speciesS. tuberosum. The pyrrolizidine alkaloid pattern of the two subspecies ofS. tuberosum reinforces the close relationship. Fresh material ofS. tuberosum contained the triterpene isobauerenol, but in herbarium material isobauerenol was lacking. InS. grandiflorum, neither fresh nor dried material contains isobauerenol. In herbarium material ofS. ibericum also no isobauerenol could be found. More extensive chemotaxonomical research is necessary to support the view thatS. abchasicum is more closely related toS. ibericum than toS. grandiflorum. 相似文献
3.
The phytochemical investigation of leaves of Melaleuca alternifolia (Maiden & Betche) Cheel led to the isolation of a new monoterpenoid glycoside derivative melaleuoside (1), together with four known monoterpenoid glycoside derivatives (2–5). Structure elucidation of these compounds was performed based on NMR spectral data and MS. Compounds 2–5 were isolated from the genus of Melaleuca for the first time. Furthermore, we also discussed the chemotaxonomic significance of the isolates in this thesis. 相似文献
4.
Phytochemical investigations on the roots of Fallopia multiflora var. Ciliinerve led to the isolation of eighteen compounds, including six chromones [2-methyl-5- carboxymethyl-7-hydroxychromone (1), 2-methyl-5-methylcarboxymethyl-7- hydroxychromone (2), 2,5-dimethyl-7-hydroxychromone (3), 2-methyl-5-hydroxymeth-yl-7-hydroxychromone (4), 2-methyl-5-carboxylicacid-7-hydroxy-chromone (5), and 2,5-dimethyl-7-hydroxychromone-7-O-β-D-glucopyranoside (6)], three lignans [Isolariciresinol (8), 5-[4-(3,4-dimethoxyphenyl)-2,3-dimethylbutyl]-1,3-benzodioxole (9), and isolariciresinol-9-O-β-D-xylopyranoside (10)], four anthraquinones [physcion-8-O-β-D-glucopyranoside (11), emodin-8-O-β-D-glucopyranoside (12), Rhein (13), and Chrysophanol (14)], three isobenzofurans [5,7-dihydroxy-isobenzofuran (15), 5-methoxy-7-hydroxy-isobenzofuran (16), and 5-methoxy-isobenzofuran-7-O-β-D-glucoside (17)], one phenolic acid [2,5-diacethylhy-droquinone (7)], and one pyran [Zanthopyranone (18)]. Among them, compounds 1, 3, 6, 13 and 14 were reported from F. multiflora var. Ciliinerve for the first time, compounds 2, 8, 10 and 15–17 were isolated from the genus Fallopia for the first time, and compounds 4, 9 and 18 were isolated for the first time from Polygonaceae family. Furthermore, the isolation of compounds 5 and 7 were reported for the first time in plants. Their structures were identified by spectroscopic methods and compared with those previously published. The chemotaxonomic significance of these isolated compounds has also been discussed. 相似文献
5.
A comparison of the morphology and of the venom alkaloids of the Australian Monomorium rothsteini complex was undertaken. These ants were collected in Australia from western New South Wales, northern Queensland, and northern Northern Territory. Additionally, samples from the M. sordidum complex and M. carinatum complex were examined. Thirteen previously described trans‐2,5‐dialkylpyrrolidines were detected in these ants, along with the novel trans‐2‐ethyl‐5‐[(Z)‐tridec‐4‐enyl]pyrrolidine ( 6 ), whose structure was confirmed by synthesis. The extent of variation and the correlation observed in the morphology and venom chemistry in M. rothsteini samples is very strongly indicative of multiple species in this complex. The presence and location of the C?C bond in 6 reinforces the remarkable structural similarity of the 2‐ethylpyrrolidines in these Monomorium species to the 2‐methylpiperidines in the venoms of many Solenopsis species, and may represent convergent evolution of biosynthetic processes in different genera of solenopsidine ants. 相似文献
6.
7.
Phytochemical investigation on the aerial parts of Melodinus hemsleyanus diels (Jahrb, Syst, 1995) led to the isolation and identification of 27 compounds, including fifteen aspidosperma-type alkaloids (1–15), four quinoline-type alkaloids (16–19), three quebrachamine-type alkaloids (20–22), and five eburna-type alkaloids (23–27). The structure of compound 1 was elucidated by means of spectroscopic analysis, including HRESIMS, and 1D and 2D NMR experiments. Compounds 1–2, 6, 10, 12, 13, 15, 16 and 20–27 are herein reported for the first time from the studied plant, while the compounds 1–2 and 21 have not previously been recorded in the genus Melodinus. The aspidosperma-type monoterpenoid indole alkaloids in M. hemsleyanus could serve as chemotaxonomic markers. 相似文献
8.
A phytochemical investigation of the whole plant of Corispermum mongolicum Iljin (Chenopodiaceae) led to the isolation of thirty-eight compounds, including thirteen phenylpropanoids (1–13), six megastigmane-type norsesquiterpenoids (14–19), eight sterols (20–27), two flavonoid glycosides (28, 29), one alkaloid (30), two aromatic glycosides (31, 32), one aliphatic glycoside (33), one triterpenoid (34), one diterpenoid (35), two cerebrosides (36, 37) and one monogalactosyldiacyl glycerol (38). The chemical structures of these compounds were elucidated on the basis of spectral data and by comparisons of spectroscopic data with reported values in the literature. Twenty-eight compounds (1, 2, 4–16, 19, 20, 23–27, 30, 32–35, 37) were first found in the family Chenopodiaceae. The chemotaxonomic significance of these compounds is discussed. 相似文献
9.
Foliage of trees from five Chinese Cupressus species was analysed for volatile monoterpenoids, sesquiterpenoids and diterpenoids. Multivariate analysis of the terpenoid data indicated that C. gigantea is most distinct, but otherwise no obvious chemotaxonomic groupings were evident. Comparison of the Cupressus analytical data with that of specimens of five Chamaecyparis species indicated that Cupressus funebris should not be reclassified into Chamaecyparis. 相似文献
10.
Cortinarius sarcoflammeus is proposed as a new species belonging to subgenus Dermocybe, on the basis of its morphological, chemical and ecological characters. The strong red-orange colour of the context and stipe
base, large spores, sphagnicolous habitat and high dermorubin content are characteristic for the new species. Holotypes of
C. huronensis and C. huronensis var. olivaceus have been examined for comparison, and their differences discussed. Photographs and line drawings of C. sarcoflammeus are added.
Received February 13, 2001 Accepted March 23, 2001 相似文献