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1.
Tivadar Kiss Kristóf Bence Cank Orsolya Orbán-Gyapai Erika Liktor-Busa Zoltán Péter Zomborszki Santa Rutkovska Irēna Pučka Anikó Németh Dezső Csupor 《BMC research notes》2017,10(1):762
Objective
Diterpene alkaloids are secondary plant metabolites and chemotaxonomical markers with a strong biological activity. These compounds are characteristic for the Ranunculaceae family, while their occurrence in other taxa is rare. Several species of the Spiraea genus (Rosaceae) are examples of this rarity. Screening Spiraea species for alkaloid content is a chemotaxonomical approach to clarify the classification and phylogeny of the genus. Novel pharmacological findings make further investigations of Spiraea diterpene alkaloids promising.Results
Seven Spiraea species were screened for diterpene alkaloids. Phytochemical and pharmacological investigations were performed on Spiraea chamaedryfolia, the species found to contain diterpene alkaloids. Its alkaloid-rich fractions were found to exert a remarkable xanthine-oxidase inhibitory activity and a moderate antibacterial activity. The alkaloid distribution within the root was clarified by microscopic techniques.2.
3.
Two hundred and thirteen fungal cultures were recovered from 88 soil samples from different parts of Indonesia; 39.4% belonged to the genusPenicillium, 19.7% to the genusAspergillus, 9.9% to the genusFusarium and the rest to different systematic groups. One hundred and fifty two cultures were antibiotically active; 80% of these were antagonists ofBacillus subtilis, 55% ofEscherichia coli, 20% ofSaccharomyces cerevisiae and 37% ofCandida pseudotropicalis. In agreement with previous observations it was found that the activity spectrum of antagonists was related to the altitude above sea level at which they were found. As the altitude increased, the incidence of antagonists with both antibacterial and antifungal activity decreased, but the incidence of antagonists with only antibacterial or only antifungal activity increased. Fungi of the generaPenicillium andAspergillus were the most frequent antibiotic producers. The incidence of penicillin producers was much lower than in collections of fungi isolated in higher latitudes (China, Bulgaria, Slovakia). 相似文献
4.
J Chełkowski P Goliński J. Perkowski A Visconti M Rakowska W Wakuliński 《Mycotoxin Research》1991,7(2):140-145
Microdochium nivale (Fusarium nivale) was found to be frequently occuring in Poland pathogen of small grain cereals heads, causing symptoms similar to those observed after infection ofFusarium species. In consecutive years since 1985 till 1989 the following percentage of wheat and rye ears infected withM. Nivale and withFusarium head blight symptoms was found: 34%, 21%, 42%, 9%, 46% (wheat) and 57%, 43%, 65%, 4%, 47% (rye) heads.However, in naturally infected rye and wheat samples (kernels and chaff), we did not detect toxins usually present in samples infected with fungi of genusFusarium — such as deoxynivalenol and derivatives. TypicalFusarium trichothecene metabolites were also not present in cultures of 11M. nivale strains, growing 3–5 weeks on rice (45% water content) at 20°C. Cultures of two typical isolates on wheat grain (strain KF 1124) and on rice (KF 245) were found to be non toxic to broiler chickens when present in amount 20–40% in their diet. It can be concluded thatM. nivale (F. nivale) representatives in Poland did not produce toxic metabolites neither under laboratory condition nor after cereal ears infection under field conditions. 相似文献
5.
The fate ofSepia in small populations ofDrosophila melanogaster 总被引:3,自引:2,他引:1
Bruce Wallace 《Genetica》1966,37(1):29-36
Asepia gene found inD. melanogaster collected in North Carolina, and wildtype flies from North Carolina, Bogotá, Barcelona, and California were used to strt 120 cultures that were maintained by mass transfers of adults every third week for more than a year. The frequency ofsepia was determined in these cultures at the termination of the experiment. Thesepia gene was present in considerable frequency (16%–65%) in all backgrounds except one; in cultures involving wildtype chromosomes from North Carolina, it was virtually eliminated. Each of the wildtype backgrounds exhibited a characteristic final frequency ofsepia, suggesting that they had reached at least quasi-stable equilibria. Although it is likely that the retention ofsepia depended upon the superiority of flies heterozygous for this mutant, the technique does not reveal whethersepia itself was involved in the apparent heterosis. 相似文献
6.
Seeds from 158 species of 39 plant families were examined for α-γ-diaminobutyric acid, which has been isolated from seed ofLathyrus sylvestris andL. latifolius by other investigators. The presence of the compound in large amounts inL. sylvestris was confirmed. Possible trace amounts ranging from 0.03 to 0.29% of the total nitrogen was found in six otherLathyrus species and from six species of related genera. Trace amounts ranging from 0.01 to 0.07% of the total nitrogen were found in 18 additional species, and none of the compound was found in the remaining 65. Evidence for the presence of the neuroactive substance was based on an elution peak occurring in the same position as that of an authentic sample. 相似文献
7.
Felipe Soares Bufalo Mauro Galetti Laurence Culot 《International journal of primatology》2016,37(3):333-349
Primates play a fundamental role as seed dispersers, particularly in tropical rainforests. Because defaunation and fragmentation are leading several primate species to local extinction, it is fundamental to understand the role of primates as effective seed dispersers. Here we present a systematic review of studies of seed dispersal by primates in a biodiversity hotspot, the Atlantic Forest of South America, to 1) highlight gaps in our knowledge, 2) determine species richness and proportion of seed species dispersed, and 3) test the relationship between primate body size and the size of dispersed species. Our review found 79 studies of the diet of six ecospecies (Callithrix, Leontopithecus, Callicebus, Sapajus, Alouatta, Brachyteles) but only 20 of these report information on seed dispersal, and none of these are on Callithrix or Callicebus. We found a strong bias in the distribution of species and regions, with most of the studies concentrated in southeastern Brazil. All ecospecies dispersed a large proportion of the seed species they handled (72.1–93.6%). Brachyteles dispersed the highest diversity of plants (N = 73), followed by Sapajus (N = 66), Leontopithecus (N = 49), and Alouatta (N = 26). Although we found no significant relationship between primate body size and the size of seeds dispersed, Brachyteles disperse a higher diversity of large-seeded species than smaller-bodied primates. These results suggest that the local extinction of large primate species may lead to dramatic changes in the plant community, as many large-seeded plants are inaccessible to smaller arboreal frugivores. We propose guidelines for future research on primate seed dispersal to enable the evaluation of seed dispersal effectiveness and to improve our understanding of the fundamental role of primates in this key ecosystem process. 相似文献
8.
Quercus crispula (=Q. mongolica var. grosseserrata) is the predominant tree species in cool temperate, mixed broadleaf/conifer forests in northern Japan. We compared 11 years of data on acorn production in a population of Q. crispula, with data on seed-insect populations, to try to answer the following questions: (1) Does Q. crispula show a regular pattern of masting? (2) How long do principal seed predators remain in diapause? (3) How do the seed predators affect the pattern of predator satiation? Q. crispula showed a tendency to alternate bearing, with significant synchrony between individual trees. The principal acorn-feeding insects (Curculio spp. weevils), which infested 25%–70% of matured acorns, generally exhibited a prolonged diapause of 2 years. No significant negative relationship was found between the rate of injury by the weevils and the density of mature acorns, indicating that simple predator satiation fails due to the synchrony of the life-cycle of acorn-feeding insects and the periodical production of acorns. However, the rate of injury by the weevils was negatively correlated with the relative abundance of mature acorns to the number of weevil larvae that had matured 2 years previously. Thus, the proportion of sound acorns notably increased in a rich crop after a disturbance in alternate bearing. Prolonged diapause of specific seed predators is critical in determining the peak year of sound-seed production. 相似文献
9.
Leslie D. Gottlieb 《Brittonia》1968,20(1):83-93
Evidence of natural hybridization betweenArctostaphylos viscida andA. canescens in southwestern Oregon was obtained from morphological studies of field populations. Hybridization occurs where populations ofA. viscida andA. canescens meet in areas where serpentine and nonserpentine soils abut. At these contacts,A. viscida forms large populations only on serpentine andA. canescens only on nonserpentine. Most of the indentifiable hybrids survive on either transitional or nonserpentine soils. The small proportion that are found on serpentine are considered to be backcrosses toA. viscida. The hybrid plants are similar to several putative species maintained in the standard floras, and it is suggested that these no longer be given taxonomic recognition. 相似文献
10.
Apekshita Singh Soom Nath Raina Vijay Rani Rajpal Anurudh K. Singh 《Physiology and Molecular Biology of Plants》2018,24(3):465-481
Total seed storage proteins were studied in 50 accessions of A. hypogaea (11 A. hypogaea ssp. hypogaea var hypogaea, 13 A. hypogaea ssp. hypogaea var hirsuta, 11 A. hypogaea ssp. fastigiata var fastigiata and 15 A. hypogaea ssp. fastigiata var. vulgaris accessions) in SDS PAGE. These accessions were also analysed for albumin and globulin seed protein fractions. Among the six seed protein markers presently used, it was found that globulin fraction showed maximum diversity (77.2%) in A. hypogaea accessions followed by albumin (52.3%), denatured total soluble protein fraction in embryo (33.3%) and cotyledon (28.5%). The cluster analysis based on combined data of cotyledons, embryos, albumins and globulins seed protein fractions demarcated the accessions of two subspecies hypogaea and fastigiata into two separate clusters supported by 51% bootstrap value, with few exceptions, suggesting the genotypes to be moderately diverse. Native and denatured total soluble seed storage proteins were also electrophoretically analysed in 27 wild Arachis species belonging to six sections of the genus. Cluster analysis using different methods were performed for different seed proteins data alone and also in combination. Section Caulorrhizae (C genome) and Triseminatae (T genome) formed one, distantly related group to A. hypogaea and other section Arachis species in the dendrogram based on denatured seed storage proteins data. The present analysis has maintained that the section Arachis species belong to primary and secondary genepools and, sections Procumbenetes and Erectoides belong to tertiary gene pools. 相似文献
11.
Bernard Krebs 《Pal?ontologische Zeitschrift》1967,41(1-2):46-59
Up to nowMachimosaurus was known only from isolated teeth. Its systematic position was uncertain. Recently discovered remains ofMachimosaurus from the Upper Jurassic of Portugal allow a reconstruction of the skull. This find proves thatMachimosaurus belongs to the crocodilian family Teleosauridae. The genus comprises the only speciesMachimosaurus hugii H. v.Meyer. The speciesMachimosaurus mosae Sauvage & Liénard is based on heterogeneous material and is unmaintainable. Osteological characteristics show that the environment ofMachimosaurus was the open seas. 相似文献
12.
Josef Měsíček 《Folia Geobotanica》1967,2(4):433-436
The chromosome number ofA. thaliana from three localities in Central Bohemia was found to be 2n=10. All the chromosomes (length 1,5–2,6μm) belong to the atelocentric type, four pairs (m) having the centromere in the median and one pair (sm) in the submedian region. In connection with the discussion on the origin ofH. suecica the author presents the following preliminary results: a) the failure to cross the tetraploidCardaminopsis arenosa (L.)Hayek withA. thaliana; b) the successful crossing of the diploidC. petraea (L.)Hiit. withA. thaliana; c) the discovery of a diploid population ofC. arenosa (2n=16) in the Tatra Mts. (Czechoslovakia). 相似文献
13.
Wheat is the most important cereal produced in Iran. A mycological survey was carried out for the first time, on the stored wheat samples in Tehran, East Azarbayejan and Mazandaran provinces in 2007. Exogenous and endogenous fungi, were isolated by the method of flotation with Malachite green agar (MGA 0.25) and Freeze blotter techniques respectively. In this study, 46 species belonging to 23 different genera were isolated.Cladosporium spp. (57.1–89.2%) andAlternaria spp. (82.4–100%) species were the predominant fungal species identified as endogenous mycoflora. The predominant exogenous fungi werePenicillium spp. (78.4–92.8%) andAspergillus spp. (71.4–85.7%) species.Fusarium proliferatum was the most prevalent species ofFusarium isolates.Aspergillus niger (39.4%) andAspergillus flavus (36.7%) were the predominantAspergillus species identified as exogenous mycoflora.Aspergillus flavus (26.6%) was the predominantAspergillus species identified as endogenous mycoflora. Flotation method with MGA 0.25 recommended for isolating of hyaline fungi from wheat cereals. In this study one isolate fromFusarium species was isolated on the basis of morphology and ribosomal internal transcribed spacer classified asFusarium langsethiae but on the basis of partial translation elongation factor-1alpha gene grouped withFusarium sporotrichioides. To our knowledge, this is the first report aboutF. cf.langsethiae in Iran and Asia. 相似文献
14.
Guo-peng Miao Juan Han Ji-feng Zhang Chuan-shu Zhu Xing Zhang 《Plant molecular biology》2017,95(1-2):51-62
Key message
TwMDR1 transports sesquiterpene pyridine alkaloids, wilforine and wilforgine, into the hairy roots of T. wilfordii Hook.f. resulting in low secretion ratio of alkaloids.Abstract
Hairy roots (HRs) exhibit high growth rate and biochemical and genetic stability. However, varying secondary metabolites in HR liquid cultures mainly remain in root tissues, and this condition may affect cell growth and cause inconvenience in downstream extraction. Studies pay less attention to adventitious root (AR) liquid cultures though release ratio of some metabolites in AR liquid cultures is significantly higher than that of HR. In Tripterygium wilfordii Hook.f., release ratio of wilforine in AR liquid cultures reached 92.75 and 13.32% in HR on day 15 of culture. To explore potential roles of transporters in this phenomenon, we cloned and functionally identified a multidrug resistance (MDR) transporter, TwMDR1, which shows high expression levels in HRs and is correlated to transmembrane transportation of alkaloids. Nicotiana tabacum cells with overexpressed TwMDR1 efficiently transported wilforine and wilforgine in an inward direction. To further prove the feasibility of genetically engineered TwMDR1 and improve alkaloid production, we performed a transient RNAi experiment on TwMDR1 in T. wilfordii Hook.f. suspension cells. Results indicated that release ratios of wilforine and wilforgine increased by 1.94- and 1.64-folds compared with that of the control group, respectively. This study provides bases for future studies that aim at increasing secretion ratios of alkaloids in root liquid cultures in vitro.15.
P. Sewes F. Alberts Marelize Daneel Adriaan A. S. Marais Denis A. Baranenko J. J. Marion Meyer 《Acta Physiologiae Plantarum》2018,40(2):24
The coca family (Erythroxylaceae) consists of trees and shrubs sub-divided into four genera: Aneulophus, Nectaropetalum, Pinacopodium, and Erythroxylum, which include species with highly valuable medicinal compounds. E. delagoense, E. emarginatum, and E. pictum are endemic to southern Africa and have great pharmaceutical potential based on their traditional uses. Previous studies have shown certain inconsistencies in terms of the presence or absence of tropane alkaloids in these species, resulting in a need for further research and clarification. Therefore, the aim of this study was to determine the seasonal variation of the immediate biosynthetic precursor of cocaine, the tropane alkaloid, ecgonine methyl ester in the three South African Erythroxylum species by means of gas chromatography–mass spectrometry, as well as to conduct a phytochemical screening for observing the presence of other potential compounds and tropane alkaloids. We found significant differences in tropane concentrations from the seasonal variation study, explaining the discrepancies in previous reports on its presence/absence in these species. Furthermore, we report for the first time on the occurrence of selected highly valuable tropane alkaloids in E. emarginatum currently used in ‘blockbuster medicine’. 相似文献
16.
Both quantitative and qualitative immunochemical methods were used for studying the mutual relationships of several spocies and the subspecies of the genusPhaseolus: Ph. vulgaris L. ssp.vulgaris, Ph. vulgaris L. ssp.aborigineus Burk.,Ph. coccineus L.,Ph. acutifolius A. Gray,Ph. lunatus L. (American endemites) andPh. aureus L. (a typical Asian bean). Protein characters of cotyledons (i.e., ?storage” proteins) of the above species were compared with the aid of antisera prepared against seed (cotyledon) proteins ofPh. vulgaris L. ssp.vulgaris, cv. Veltruská Saxa, using
- (a)the whole complex of cotyledon protein, 相似文献
17.
Biologically active substances and antioxidant activity of extracts from leaves and inflorescences of nine representatives of the genus Spiraea L. growing on the territory of the Far East of Russia were investigated. Widespread species of the genus Spiraea (S. salicifolia, S. media var. media, S. betulifolia and S. ussuriensis subsp. ussuriensis) have the highest levels of biologically active substances. The inflorescences of spiraeas there contain more flavonols (up to 3.9%), oxycinnamic acids (up to 1.2%), catechins (up to 5.7%) and saponins (up to 5.1%) compared to their leaves, and there are more tannins (up to 11.6%) in the leaves. Among the Far Eastern representatives of the genus Spiraea, S. betulifolia and S. beauverdiana (section Calospira), S. humilis and S. salicifolia (section Spiraria), S. pubescens and S. media var. media (section Chamaedryon) are promising antioxidants. Plants of the genus Spiraea probably contain water-soluble antioxidant compounds of phenolic type, because the antioxidant activity of aqueous extracts in the leaves and inflorescences of spiraeas is higher (0.16–2.79 mg/g) than that of water-alcoholic compounds (0.06–2.54 mg/g). The antioxidant activity in the leaves of spiraeas is generally higher than that in the inflorescence. A reliable positive correlation is observed between the antioxidant activity of aqueous extracts from the organs of spiraeas and a content of oxycinnamic acids. 相似文献
18.
19.
Ghillean T. Prance 《Brittonia》1968,20(3):203-204
Maranthes, a genus well known in Africa and Asia, has not been recorded previously in the New World.Couepia panamensis, thought to be endemic to Panama, was found to be synonymous withMaranthes corymbosa, a widespread Asiatic species, and it is reduced into synonymy, making the first American record ofMaranthes. The relationship ofMaranthes toCouepia, and the unusual distribution ofM. corymbosa are discussed. 相似文献
20.
Harvester ants have long been known to exhibit interspecific seed preference and this preference has been thought to be associated with distance in a manner analogous with optimal foraging theory. However, little attention has been given to how intraspecific seed preference changes or how microhabitat (i.e. the composition of the terrain that the ants are moving through) impacts seed harvesting preference. We addressed these questions by conducting seed harvesting experiments in three different Ephedra viridis populations that contain harvester ants (Pogonomyrmex occidentalis) by using only E. viridis seeds and conducting trials over multiple distances and varying degrees of microhabitat cover. We found that increased microhabitat cover and increased seed mass decrease the likelihood of E. viridis seeds being harvested much more dramatically than distance. However, we found no effect of distance or microhabitat cover on which E. viridis seeds were harvested. We conclude that harvester ant E. viridis seed preference is distance and microhabitat independent. However, increases in microhabitat cover negatively impacts the likelihood of P. occidentalis harvesting E. viridis seeds of any size. Our findings suggest that harvester ant foraging behavior is influenced by structure of the microhabitat more than by distance. This provides a new context on how harvester ant foraging behavior and effectiveness should be considered. 相似文献