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1.
Monoalgal cultured Eutreptielia gymnastica contained chlorophyll a and b. The acetylenic carotenoids diatoxanthin and diadinoxanthin were among the main xanthophylls while their non-acetylenic analogues zeaxanthin and antheraxanthin were absent. The structurally most complex carotenoid was identical with neoxanthin. Three of the xanthophylls isolated could not be positively correlated with carotenoids previously reported from the Euglenophyceae. The ketocarotenoids astaxanthin, canthaxanthin and echinenone were absent.  相似文献   

2.
Besides neoxanthin and deepoxineoxanthin, the main xanthophylls in the petals of Mimulus guttatus, an additional pigment, mimulaxanthin, has been obtained; it is 3,3′–5,5′-tetrahydroxy-6′-hydro-7-dehydro-β-carotene. Its neoxanthin-like spectrum is not changed by acids. Two hydroxyl groups are acetylatable. The diacetate can be silylated to a di(trimethylsilyl)-ether, and with acidic alcohols, yields a monoether. With CHCl3 plus HCl 18 defined reaction-products are obtained, one of which is 3,3′-di-hydroxy-7,8-didehydro-α-carotene (monadoxanthin). One of the LiAlH4-reduction products of neoxanthin is identical with mimulaxanthin, whereas mimulaxanthin with LiAlH4 gives an acetylenic derivative. These results have been confirmed by IR spectrometry. Mimulaxanthin is not an artefact formed during extraction and purification.  相似文献   

3.
Chromone glucosides, takanechromones A-C (1, 2 and 5) and chromanone glucosides, named takanechromanones A and B (3 and 4), were isolated from the methanolic extracts of Hypericumsikokumontanum together with 27 known compounds. Their structures were established based on spectroscopic evidence. The isolated compounds and some chromone derivatives were assayed for antimicrobial activity against Helicobacter pylori and cytotoxicity against human cancer cell lines.  相似文献   

4.
In this paper we analyze through a polyphasic approach several Bradyrhizobium strains isolated in Spain and Morocco from root nodules of Retama sphaerocarpa and Retama monosperma. All the strains have identical 16S rRNA genes and their closest relative species is Bradyrhizobium lablabi CCBAU 23086T, with 99.41% identity with respect to the strain Ro19T. Despite the closeness of the 16S rRNA genes, the housekeeping genes recA, atpD and glnII were divergent in Ro19T and B. lablabi CCBAU 23086T, with identity values of 95.71%, 93.75% and 93.11%, respectively. These differences were congruent with DNA–DNA hybridization analysis that revealed an average of 35% relatedness between the novel species and B. lablabi CCBAU 23086T. Also, differential phenotypic characteristics of the new species were found with respect to the already described species of Bradyrhizobium. Based on the genotypic and phenotypic data obtained in this study, we propose to classify the group of strains isolated from R. sphaerocarpa and R. monosperma as a novel species named Bradyrhizobium retamae sp. nov. (type strain Ro19T = LMG 27393T = CECT 8261T). The analysis of symbiotic genes revealed that some of these strains constitute a new symbiovar within genus Bradyrhizobium for which we propose the name “retamae”, that mainly contains nodulating strains isolated from Retama species in different continents.  相似文献   

5.
The oyster ovarian parasite Marteilioides chungmuensis has been reported from Korea and Japan, damaging the oyster industries. Recently, Marteilioides-like organisms have been identified in other commercially important marine bivalves. In this study, we surveyed Marteilioides infection in the Manila clam Ruditapes philippinarum, Suminoe oyster Crassostrea ariakensis, and Pacific oyster Crassostrea gigas, using histology and Marteilioides-specific small subunit (SSU) rDNA PCR. The SSU rDNA sequence of M. chungmuensis (1716 bp) isolated from C. gigas in Tongyoung bay was 99.9% similar to that of M. chungmuensis reported in Japan. Inclusions of multi-nucleated bodies in the oocytes, typical of Marteilioides infection, were identified for the first time in Suminoe oysters. The SSU rDNA sequence of a Marteilioides-like organism isolated from Suminoe oysters was 99.9% similar to that of M. chungmuensis. Marteilioides sp. was also observed from 7 Manila clams of 1840 individuals examined, and the DNA sequences of which were 98.2% similar to the known sequence of M. chungmuensis. Unlike Marteilioides infection of Pacific oysters, no remarkable pathological symptoms, such as large multiple lumps on the mantle, were observed in infected Suminoe oysters or Manila clams. Distribution of the infected Manila clams, Suminoe oysters and Pacific oysters was limited to small bays on the south coast, suggesting that the southern coast is the enzootic area of Marteilioides infection.  相似文献   

6.
7.
We isolated 33 nodule bacteria from the legume Alhagi sparsifolia growing in the desert of northwest China. They fell into three groups by restriction analysis of their rrs (small subunit ribosomal RNA) genes, and these, together with dnaK and dnaJ genes, were sequenced from representative isolates to assess their taxonomic position by phylogenetic analysis. The bacteria in each group belonged to different lineages that might represent three different new Mesorhizobium species, two of which form a novel clade very distinct from other species in the genus. Most A. sparsifolia symbionts harboured closely related nodA and nodC genes forming new lineages. The presence of these closely related symbiosis genes in various genomic backgrounds and the incongruence observed between the different gene phylogenies indicate a history of horizontal gene transfer of symbiosis genes between the A. sparsifolia symbionts.  相似文献   

8.
Nine (1–9) and seven (1–6, 10) compounds were isolated from the fruits of Sonneratia caseolaris and Sonneratia ovata, respectively. Their structures were identified by comparing their MS and NMR data as well as the physical properties with the literature. All the isolated compounds were screened against a rat glioma C-6 cell line using the MTT assay method; only compounds (-)-(R)-nyasol (1), (-)-(R)-4′-O-methylnyasol (2) and maslinic acid (6) were found to show moderate cytotoxic activity. Our findings from these two kinds of fruits can be used as a foundation for further chemotaxonomic studies on Sonneratia species. The nor-lignans (1, 2) and 6H-benzo[b,d]pyran-6-one derivatives (3, 4) were isolated from this genus for the first time, indicating that these two classes of compounds may tentatively be considered as taxonomic markers for Sonneratia genus.  相似文献   

9.
In a chemosystematic investigation of three Southern hemisphere species of Veronica, namely the Australian Veronica derwentiana Andrews and Veronica perfoliata R.Br. (formerly Derwentia species), and the New Zealand Veronica catarractae G. Forster (formerly a species of Parahebe), the water-soluble constituents were isolated and identified by spectroscopic methods. Apart from other iridoid glucosides common to the genus, three unusual substituted benzoyl esters of aucubin (derwentiosides A–C) were obtained from V. derwentiana and a chlorinated iridoid glycoside (catarractoside) from V. catarractae in addition to other iridoids common to the genus. The chemical profile of V. perfoliata is similar to that of Northern hemisphere species of Veronica because of the presence of characteristic 6-O-catalpol esters. The profile of V. derwentiana is unique, since 6-O-esters of aucubin rather than of catalpol dominate, however, the acyl groups are the same as those present in catalpol esters found in some other Veronica sections. V. catarractae also contains one of the catalpol esters characteristic of Veronica, but in addition three 6-O-rhamnopyranosyl substituted iridoid glycosides, one of which is 6-O-rhamnopyranosylcatalpol. Esters of the latter compound are previously only known from the more derived species in recent phylogenetic trees of sect. Hebe to which V. catarractae now also belongs, but as a more basal member.  相似文献   

10.
The carotenoids of the loquat fruit Eriobotrya japonica Golden Nugget variety, were investigated. They were identified according to their chromatographic, spectrophotometric and chemical properties and compared with standard pigments. For some of the carotenoids, MS were determined. Pulp and peels were investigated separately. The main pattern of the pulp carotenoids was β-carotene (33%), γ-carotene (6%), cryptoxanthin (22%), lutein, violaxanthin and neoxanthin, each about 3–4%. The peel, with a carotenoid content 5 times as high, had a similar pattern, but the ratio between the main pigments differed: β-carotene (50%); γ-carotene (5%); cryptoxanthin (5%); lutein (13%); violaxanthin, neoxanthin, 3–4%. The carotenoids of the loquat (subfamily Maloideae) were very similar to those of the apricot (Prunus armeniaca-subfamily Prunoideae) both of the family of Rosaceae. The intergeneric differences are more pronounced, which is of possible taxonomic significance. The lower concentration of cryptoxanthin and the high concentration of lutein in the peels is noteworthy and of biosynthetic interest.  相似文献   

11.
A new halimane diterpenoid and the previously known labdane rhinocerotinoic acid were isolated from Plectranthus ornatus Codd. In addition, a new monoacetyl derivative of the abietane coleon U was found among the constituents of Plectranthus grandidentatus Gürke. These diterpenes could be significant from both chemotaxonomic and biogenetic points of view.  相似文献   

12.
Sterically hindered cis-carotenoids 1 and 2 were isolated from seeds of the oriental bitter sweet, Celastrus orbiculatus. Their structures were determined to be (3′Z, 5′Z)-celaxanthin and (3′Z, 5′Z)-torulene, respectively, on the basis of spectroscopic data and iodine-catalyzed stereomutation. This is the first report on carotenoids with a 3Z, 5Z configuration.  相似文献   

13.
Free-living amoebae are widely distributed in aquatic environments and their hygienic, medical and ecological relationships to man are increasingly important. The purpose of this study was to isolate free-living amoebae from water-hyacinth root (Eichhornia crassipes) and the water of an urban lake in Mexico City. Five grams of wet root were seeded on non-nutritive agar with Enterobacter aerogenes (NNE). Water samples were concentrated by centrifugation at 1200g for 15 min and the pellet was seeded on NNE. Of the 16 isolated genera, 10 were detected in both habitats. The most frequent were Vannella in root and Acanthamoeba and Naegleria in water. The total number of isolates and genera isolated from root was higher than that isolated from water. The differences between root and water are probably due to the morphological characteristics of water-hyacinth root, which provides a large habitat and refuge area for many organisms.  相似文献   

14.
Iridoid glycosides, 2′,3′,6′-tri-O-acetyl-4′-O-trans-p-(O-β-d-glucopyranosyl)coumaroyl-7-ketologanin (1), 2′-O-caffeoylloganic acid (2), 2′-O-p-hydroxybenzoylloganic acid (3), 2′-O-trans-p-coumaroylloganic acid (4), and 2′-O-cis-p-coumaroylloganic acid (5), were isolated from whole plants of Gentiana loureirii along with six known iridoids, 7-ketologanin (6), loganin (7), loganic acid (8), sweroside, boonein, and isoboonein, and three other known compounds. Their structures were elucidated by spectroscopic means and chemical correlations. The isolated iridoids were evaluated for antibacterial and antioxidant activities, but were either inactive or very weakly active.  相似文献   

15.
Corydines, isocorydines, and analogous aporphine alkaloids were isolated from the leaves of Aristolochia lagesiana var. intermedia, together with three bisaporphine salts (lagesianines B-D). Their structures were determined by chemical derivatizations and spectroscopic analyses. Lagesianines B and C are the first examples of N-CH2-N′ and C-2-O-C-1′ linked dimeric aporphine alkaloids, respectively, while the monomeric units of lagesianine D, which has a carbon skeleton, are linked through C-7-C-5′ via an ethane-1,2-diol group (C-7-CHOHCHOH-C-5′).  相似文献   

16.
A cell-free system prepared from an axenic culture of the alga Amphidinium carterae converted [14C]zeaxanthin into neoxanthin and then into peridinin (62%) and diadinoxanthin (38%). Peridinin, therefore, is made by the excision of three carbon atoms from a C40 carotenoid and the acetylene group of diadinoxanthin is formed from the allene of neoxanthin, rather than the reverse.  相似文献   

17.
18.
Two homologous series of n-paraffins and sec-alcohols from C20 to C34 or C35 were isolated a wax constituents of a liverwort, Isotachis japonica. In both series, odd-members were predominant compared with even-members: the ratio of the total amount of odd- to total amounts of even-members was 3·9 in the n-paraffin homologues, and 16·5 in the sec-alcohol homologues.  相似文献   

19.
In a project to isolate and characterise anti-staphylococcal compounds from members of the genus Hypericum, a dibenzofuran and a pyranone were isolated from the dichloromethane and hexane extracts of Hypericum revolutum ssp. revolutum Vahl (Guttiferae) and Hypericum choisianum Wall. ex. N. Robson (Guttiferae), respectively. The structures of these compounds were elucidated by 1- and 2D-NMR spectroscopy and mass spectrometry as 3-hydroxy-1,4,7-trimethoxydibenzofuran (1) and 4-(3-O-3″)-3″-methylbutenyl-6-phenyl-pyran-2-one (2). The metabolites were evaluated against a panel of multidrug-resistant strains of Staphylococcus aureus. Compound 1 exhibited a minimum inhibitory concentration (MIC) of 256 μg/ml, whereas compound 2 was inactive at a concentration of 512 μg/ml.  相似文献   

20.
The diterpenes, strobol, strobal, manoyl oxide, and cis- and trans-abienols, were isolated as major constituents of the extract of Pinus strobus L. cortex tissue. The known triterpene, 3β-methoxy-14-serraten-21-one, was also found. A polyprenol was isolated from the needle extractives.  相似文献   

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