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排序方式: 共有63条查询结果,搜索用时 15 毫秒
1.
Elena V. Girich Anton N. Yurchenko Olga F. Smetanina Phan Thi Hoai Trinh Ngo Thi Duy Ngoc Mikhail V. Pivkin Roman S. Popov Evgeny A. Pislyagin Ekaterina S. Menchinskaya Ekaterina A. Chingizova Shamil S. Afiyatullov Ekaterina A. Yurchenko 《Marine drugs》2020,18(12)
Low molecular weight secondary metabolites of marine fungi Aspergillus flocculosus, Aspergillus terreus and Penicillium sp. from Van Phong and Nha Trang Bays (Vietnam) were studied and a number of polyketides, bis-indole quinones and terpenoids were isolated. The structures of the isolated compounds were determined by 1D and 2D NMR and HR-ESI-MS techniques. Stereochemistry of some compounds was established based on ECD data. A chemical structure of asterriquinone F (6) was thoroughly described for the first time. Anthraquinone (13) was firstly obtained from a natural source. Neuroprotective influences of the isolated compounds against 6-OHDA, paraquat and rotenone toxicity were investigated. 4-Hydroxyscytalone (1), 4-hydroxy-6-dehydroxyscytalone (2) and demethylcitreoviranol (3) have shown significant increasing of paraquat- and rotenone-treated Neuro-2a cell viability and anti-ROS activity. 相似文献
2.
Alexandra S. Silchenko Anatoly I. Kalinovsky Sergey A. Avilov Pelageya V. Andrijaschenko Roman S. Popov Pavel S. Dmitrenok Ekaterina A. Chingizova Vladimir I. Kalinin 《Marine drugs》2020,18(11)
Six new monosulfated triterpene tetra-, penta- and hexaosides, namely, the kurilosides A1 (1), A2 (2), C1 (3), D (4), E (5) and F (6), as well as the known earlier kuriloside A (7), having unusual non-holostane aglycones without lactone, have been isolated from the sea cucumber Thyonidium (= Duasmodactyla) kurilensis (Levin) (Cucumariidae, Dendrochirotida), collected in the Sea of Okhotsk near Onekotan Island from a depth of 100 m. Structures of the glycosides were established by 2D NMR spectroscopy and HR-ESI mass spectrometry. Kurilosides of the groups A and E contain carbohydrate moieties with a rare architecture (a pentasaccharide branched by C(4) Xyl1), differing from each other in the second monosaccharide residue (quinovose or glucose, correspondingly); kurilosides of the group C are characterized by a unique tetrasaccharide branched by a C(4) Xyl1 sugar chain; and kurilosides of the groups D and F are hexaosides differing from each other in the presence of an O-methyl group in the fourth (terminal) sugar unit. All these glycosides contain a sulfate group at C-6 of the glucose residue attached to C-4 Xyl1 and the non-holostane aglycones have a 9(11) double bond and lack γ-lactone. The cytotoxic activities of compounds 1–7 against mouse neuroblastoma Neuro 2a, normal epithelial JB-6 cells and erythrocytes were studied. Kuriloside A1 (1) was the most active compound in the series, demonstrating strong cytotoxicity against the erythrocytes and JB-6 cells and a moderate effect against Neuro 2a cells. 相似文献
3.
I. G. Shirokikh L. M. Kozlova A. A. Shirokikh F. A. Popov E. V. Tovstik 《Eurasian Soil Science》2017,50(7):826-831
The population density and structure of complexes of soil microscopic fungi in the rhizosphere and rhizoplane of spring wheat (Triticum aestivum L.), plant damage by root rot and leaf diseases, and crop yield were determined in a stationary field experiment on a silty loamy soddy-podzolic soil (Albic Retisol (Loamic, Aric)) in dependence on the soil tillage technique: (a) moldboard plowing to 20–22 cm and (b) non-inversive tillage to 14–16 cm. The results were treated with the two-way ANOVA method. It was shown that the number of fungal propagules in the rhizosphere and rhizoplane of plants in the variant with non-inversive tillage was significantly smaller than that in the variant with plowing. Minimization of the impact on the soil during five years led to insignificant changes in the structure of micromycete complexes in the rhizosphere of wheat. The damage of the plants with root rot and leaf diseases upon non-inversive tillage did not increase in comparison with that upon plowing. Wheat yield in the variant with non-inversive tillage was insignificantly lower than that in the variant with moldboard plowing. The application of biopreparations based on the Streptomyces hygroscopicus А4 and Pseudomonas aureofaciens BS 1393 resulted in a significant decrease of plant damage with leaf rust. 相似文献
4.
Alkaloids isolated from Crinum species have been reviewed for the period 1985-2000. Non-nitrogenous compounds have been surveyed for the first time. Botanical classification and biological activity are discussed. Spectral data literature sources are listed. 相似文献
5.
Oz Barazani Azat Atayev Bakhtiyor Yakubov Vladimir Kostiukovsky Konstantin Popov Avi Golan-Goldhirsh 《Genetic Resources and Crop Evolution》2003,50(4):383-389
Seedlings of Pistacia vera L. developed from seeds of two separate populations in Turkmenistan, Kepele and Agachli, were evaluated for their growth potential and genetic polymorphism. Plant growth rate as well as random amplified polymorphic DNA (RAPD) analysis showed distinct differences between the two populations. In plant height growth rate, 17 Agachli accessions were 1.3 times higher on average than that of 10 accessions of Kepele (significant at p = 0.046) and 1.2 times higher for trunk diameter growth rate (p = 0.062). Cluster analysis divided most accessions into two main genetic groups according to their geographic origin. The Agachli group was further divided into two subgroups. One Kepele accession (K4), was genetically different from the rest and clustered on a separate outgroup. Two Agachli accessions (A12 and A17) were outside the two main populations clusters. Accessions K9 and K10 from Kepele were exceptional and were clustered in each of the two Agachli's subgroups, indicating a close genetic relationship between the two populations. In addition, high similarity values (0.58–1.00) and small genetic distances reflect plausible gene flow between Kepele and Agachli, which are 100 Km apart. Mantel test revealed significant relationship between the RAPD and the morphological traits matrices, pointing to the genetic basis for the measured differences in the growth rate. Growing the accessions on the same plot, under similar conditions enabled the evaluation of genotypic differences. The combination of morphological traits and molecular markers will further assist in preservation of genetic variability and cultivation of useful genotypes of P. vera L. 相似文献
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8.
V. E. Popov 《Eurasian Soil Science》2006,39(3):307-313
Dark-colored particles in the coarse fractions of sandy soils were found to concentrate 137Cs. Up to 94% of the fractional 137Cs was associated with these particles in the sand and coarse silt fractions, although their relative mass did not exceed 1–5%. The concentrations of 137Cs in the dark-colored particles were up to 400 times higher than those in the light-colored particles. The high values of the radiocesium interception potential (RIP(K) = 1600–4600 mM/kg) indicate the presence of clay minerals in the dark particles. 相似文献
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10.
Igor Popov 《水产资源保护:海洋与淡水生态系统》2017,27(3):717-730
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