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1.
Adenophora triphylla var. japonica (Campanulaceae) yielded two new alkaloids, the 6-C-butyl derivative of 2R,5R-bis(hydroxymethyl)-3R,4R-dihydroxypyrrolidine (DMDP) and alpha-1-C-ethyl-fagomine, together with the known alkaloids 1,4-dideoxy-1,4-imino-D-arabinitol, 1-deoxynojirimycin, and 1-deoxymannojirimycin. 6-C-Butyl-DMDP showed inhibitory activity toward almond beta-glucosidase (IC50 = 68 microM), whereas alpha-1-C-ethyl-fagomine inhibited bovine liver beta-galactosidase (IC50 = 29 microM).  相似文献   

2.
The aim of this study was to evaluate the anesthesia induction and recovery times of sub-adult and post-larvae white shrimp (Litopenaeus vannamei) that were treated with eugenol and the essential oils (EOs) from Lippia alba and Aloysia triphylla. Oxidative stress parameters in the hemolymph of this species were also analyzed. The concentrations of eugenol, A. triphylla EO and L. alba EO recommended for anesthesia were 200, 300 and 750 μL L(-1) for sub-adults and 175, 300 and 500 μL L(-1) for post-larvae, respectively. The concentrations studied during the transport of sub-adults were between 20 and 50 μL L(-1) eugenol, 20-30 μL L(-1)A. triphylla EO and 50 μL L(-1)L. alba EO. For post-larvae, the optimal concentrations for transport were 20 μL L(-1) eugenol and between 20 and 50 μL L(-1)A. triphylla EO. The white shrimp sub-adults that were exposed to A. triphylla EO (20 μL L(-1)) showed increases in their total antioxidant capacities (150%), catalase (70%) and glutathione-S-transferase (615%) activity after 6 h. L. alba EO (50 μL L(-1)) and eugenol (20 μL L(-1)) also increased GST activity (1292 and 1315%) after 6 h, and eugenol (20 μL L(-1)) decreased the total antioxidant capacity (100%). Moreover, concentrations above 30 μL L(-1) for the EOs of A. triphylla and L. alba and 20 μL L(-1) eugenol were effective at inducing anesthesia and improving the antioxidant system against reactive oxygen species (ROS) after 6 h.  相似文献   

3.
The anti-inflammatory properties of Loasa speciosa and Loasa triphylla (Loasaceae), Urtica leptuphylla and Urera baccifera (Urticaceae), and Chaptalia nutans (Asteracene) were studied using the carregeenan induced rat paw edema model. Aqueous extracts of each plant were made according to the ethnobotanical use. The hippocratic assay was made with female rats; the dose used was 500 mg/kg i.p. and the control group received 0.5 ml of n.s.s.. All the animals treated showed hypothermia, and those treated with the extracts of Chaptalia nutans, Urera baccifera and Urtica leptuphylla showed an increased colinergic activity. Acute toxicities of the aqueous extracts were studied in mice an the mean lethal doses ranged between 1.0226 and 1.2022 g/kg. The extracts of Urera baccifera, Chaptalia nutans, Loasa speciosa and Loasa triphylla (500 mg/kg i.p.) showed an anti-inflammatory activity comparable with that of indomethacin. The extracts of U. baccifera and C. nutans, which showed the greatest anti-inflammatory activity, did not show it when used orally (500 mg/kg p.o.).  相似文献   

4.
柠檬马鞭草快速繁殖技术研究   总被引:1,自引:0,他引:1  
选择柠檬马鞭草带腋芽的幼嫩茎段为外植体进行快速繁殖。结果表明,腋芽诱导的最适培养基是MS基本培养基附加6-BA0.5~1.0mg/L和IBA0.1~0.3mg/L.外植体腋芽能正常萌发生长,并迅速进入增殖状态,20d转接1次,增殖倍数存3倍以上,最适生根培养基是1/2MS基本培养基附加IBA0.5mg/L,诱导生根率达99%。将生根苗移入苗盆。30d的成活率在85%以上。  相似文献   

5.
Four flavonol glycosides from Achlys triphylla.   总被引:1,自引:0,他引:1  
Four new flavonol glycosides were isolated from the underground parts of Achlys triphylla in addition to eight known compounds. By means of spectroscopic analysis, the structures were characterized as isorhamnetin 3-glucosyl(1----3)galactoside, isorhamnetin 3-[6'acetylglucosyl(1----3)galactoside], isorhamnetin 3-[4'6'-di-acetylglucosyl(1----3)galactoside], and syringetin 3-[6'-acetylglucosyl(1----3)galactoside], respectively. In the aerial parts of the plant, seven known compounds were also confirmed.  相似文献   

6.
Zusammenfassung Die Blüten vonLoasa triphylla, Blumenbachia hieronymi undCajophora lateritia sind sich in ihrer Ontogenese sehr ähnlich. Das Androeceum besitzt zehn Bildungszentren, fünf episepale und fünf epipetale: Die episepalen Bildungszentren liefern drei Primordien, die später gemeinsam zu einer Nektarschuppe hochwachsen; die epipetalen bestehen aus zwei sich zentrifugal entwickelnden Doppelreihen von zickzackförmig angeordneten Primordien, von denen das Anfangsglied jeweils zu einem Staminodium wird (Diagramm, Abb. 38).Ein völlig anderes Bild bietet das Androeceum vonMentzelia arborescens. Das Androeceum weist fünf episepale nicht gegeneinander abgrenzbare Bildungszentren auf. Alle Stamina sind fertil und werden in zentripetaler Folge angelegt (Diagramm, Abb. 18). Aus diesen und anderen Gründen wird vorgeschlagen, die Mentzelien aus den Loasaceae auszuschließen.
Developmental studies on flowers of loasaceae
Summary The flowers ofLoasa triphylla, Blumenbachia hieronymi andCajophora lateritia have a very similar ontogeny. The androecium consists of ten complex organs, five in episepalous and five in epipetalous position. The episepalous organs are composed of three primodia, which later become a nectary; in the epipetalous complexes numerous primordia originate centrifugally in two zigzag-like double rows, in which the first member develops to a staminode, while the others become fertile stamens (see diagram Fig. 38).InMentzelia arborescens we can assume five episepalous complex organs, which are fused laterally. All stamens are fertile and originate in a centripetal sequence (see diagram Fig. 18). It is proposed to excludeMentzelia from the Loasaceae.


Herrn Prof. Dr. L.Brauner zum 75. Geburtstag gewidmet.  相似文献   

7.
The minimum inhibitory concentration (MIC) of Origanum vulgare, Aloysia triphylla, Aloysia polystachya and Mentha piperita essential oils (EOs) against Fusarium verticillioides M 7075 (F. moniliforme, Sheldon) were assessed, using the semisolid agar antifungal susceptibility (SAAS) technique. O. vulgare, A. triphylla, A. polystachya and M. piperita EOs were evaluated at final concentrations of 10, 20, 40, 50, 100, 200, 250, 500, 1000 and 1500 εl per litre (εl/l) of culture medium. A. triphylla and O. vulgare EOs showed the highest inhibitory effects on F. verticillioides mycelial development. This inhibition was observed at 250 and 500 εl/l for EOs coming from Aloysia triphylla and O. vulgare, respectively. Thus, the effects of EOs on FB1 production were evaluated using corn grain (Zea mays) as substrate. The EOs were inserted on the 5th, 10th, 15th and 20th day of maize postinoculation with a conidia suspension of F. verticillioides. O. vulgare and A. triphylla were applied to give final concentrations of 30 ppm and 45 ppm, respectively. Different effects were observed in the toxicogenicity at the 20th day treatment. The O. vulgare EO decreased the production level of FB1 (P < 0.01) while A. triphyla EO increased it (P < 0.001) with respect to those obtained in the inoculated maize, not EOs treated. Results obtained in the present work indicate that fumonisin production could be inhibited or stimulated by some constituents of EOs coming from aromatic plants. Further studies should be performed to identify the components of EOs with modulatory activity on the growth and fumonisins production of Fusarium verticillioides.  相似文献   

8.
var1 Gene on the mitochondrial genome of Torulopsis glabrata   总被引:5,自引:0,他引:5  
We have cloned and sequenced a region of the Torulopsis glabrata mitochondrial genome homologous to the Saccharomyces cerevisiae var1 gene (var1Sc). An open reading frame that could encode a protein of 339 amino acids was found with 72.7% amino acid and 85.3% nucleotide sequence homology to the S. cerevisiae var1 gene. The T. glabrata gene (var1Tg) is transcribed yielding two stable RNAs, a more abundant 13.5 S RNA and a less abundant 18 S species. We have also identified a candidate for a T. glabrata var1 protein among mitochondrial translation products labeled in isolated mitochondria. The var1Tg gene is even more A + T-rich (93%) than var1Sc (89.6%) and has conserved the strong codon bias of var1Sc. Major differences between the two sequences were found. Significant among these are that no GC clusters are found in var1Tg and the sequences surrounding each of the sites where known polymorphisms exist in var1Sc have deletions at the corresponding sites in var1Tg. These data are discussed with respect to possible origins of these var1 genes and translocation of GC clusters in S. cerevisiae mitochondrial DNA.  相似文献   

9.
Westphal T  Reuter G 《Genetics》2002,160(2):609-621
Compact chromatin structure, induction of gene silencing in position-effect variegation (PEV), and crossing-over suppression are typical features of heterochromatin. To identify genes affecting crossing-over suppression by heterochromatin we tested PEV suppressor mutations for their effects on crossing over in pericentromeric regions of Drosophila autosomes. From the 46 mutations (28 loci) studied, 16 Su(var) mutations of the nine genes Su(var)2-1, Su(var)2-2, Su(var)2-5, Su(var)2-10, Su(var)2-14, Su(var)2-15, Su(var)3-3, Su(var)3-7, and Su(var)3-9 significantly increase in heterozygotes or by additive effects in double and triple heterozygotes crossing over in the ri-p(p) region of chromosome 3. Su(var)2-2(01) and Su(var)2-14(01) display the strongest recombinogenic effects and were also shown to enhance recombination within the light-rolled heterochromatic region of chromosome 2. The dominant recombinogenic effects of Su(var) mutations are most pronounced in proximal euchromatin and are accompanied with significant reduction of meiotic nondisjunction. Our data suggest that crossing-over suppression by heterochromatin is controlled at chromatin structure as well as illustrate the possible effects of heterochromatin on total crossing-over frequencies in the genome.  相似文献   

10.
Weiler KS 《Genetics》2007,177(1):167-178
The importance of a gene's natural chromatin environment for its normal expression is poignantly illustrated when a change in chromosome position results in variable gene repression, such as is observed in position effect variegation (PEV) when the Drosophila melanogaster white (omega) gene is juxtaposed with heterochromatin. The Enhancer of variegation 3-9 [E(var)3-9] gene was one of over a hundred loci identified in screens for mutations that dominantly modify PEV. Haploinsufficiency for E(var)3-9 enhances omegam4 variegation, as would be expected from increased heterochromatin formation. To clarify the role of E(var)3-9 in chromosome structure, the gene has been cloned and its mutant alleles characterized. The involvement of E(var)3-9 in structure determination was supported by its reciprocal effects on euchromatic and heterochromatic PEV; E(var)3-9 mutations increased expression of a variegating heterochromatic gene in two tissue types. E(var)3-9 mutations also had a recessive phenotype, maternal effect lethality, which implicated E(var)3-9 function in an essential process during embryogenesis. Both phenotypes of E(var)3-9 mutations were consistent with its proposed function in promoting normal chromosome structure. The cloning of E(var)3-9 by classical genetic methods revealed that it encodes a protein with multiple zinc fingers, but otherwise novel sequence.  相似文献   

11.
A retrospective study of 20 patients with cryptococcal meningitis and their isolated strains was performed. Cryptococcus neoformans var. neoformans was recovered from 14 (70%) cases, and var. gattii was recovered from six (30%) patients. Twelve patients had AIDS (all carrying var. neoformans), two had other diseases (one with var. neoformans and one var. gattii) and there was no identifiable underlying disease in six (one var. neoformans and five var. gattii). Fourteen patients (11 var. neoformans and three var. gattii) resided in the Mexico City area, where a temperate climate is prevalent, and there were six cases (three var. neoformans and three var. gattii) from states with a tropical/subtropical climate. Although there was no significant statistical difference between the two varieties, the fatal outcome was higher in patients with var. neoformans. The disease caused by var. gattii strains was characterized by a higher opening pressure, more inflamatory changes of CSF and a longer clinical course (delayed clinical and mycological cure). Cryptococcus neoformans var. gattii is a significant cause of cryptococcal meningitis in patients without underlying diseases in Mexico.  相似文献   

12.
膜荚黄芪与蒙古黄芪幼苗的光能利用及其耐光性研究   总被引:2,自引:0,他引:2  
宋宁  郭平毅  原向阳 《西北植物学报》2011,31(11):2283-2289
以盆栽膜荚黄芪和蒙古黄芪幼苗为试验材料,测量2种黄芪叶片的光合速率、叶绿素荧光参数、光能利用率及耐光性等指标的日变化,以探讨它们的光能利用、热耗散以及耐光性差异.结果表明:(1)随着太阳光合有效辐射的日变化进程推进,2种黄芪的初始荧光(F0)、非光化学淬灭(NPQ)、PSⅡ调节性能量耗散量子产最(YNPQ)先升高后降低...  相似文献   

13.
The DBL (MCF-2) proto-oncogene is a prototype guanine nucleotide exchange factor (GEF) that modulates the Rho family of GTPases. In this communication we describe the isolation of three novel splicing variants of Dbl. The prototype Dbl gene (designated var.1 here) contains 25 exons, while splicing variant 2 (var.2) lacks exons 23 and 24. Var.3 contains additional 3 exons from 5(')-UTR in place of exon 1, while var.4, var.2, and var.3 contain a 48bp insertion between exons 10 and 11, resulting in the insertion of 16 amino acids. We found that var.1 was expressed only in brain, whereas var.3 was expressed in heart, kidney, spleen, liver, and testis, and var.4 in brain, heart, kidney, testis, placenta, stomach, and peripheral blood. The Dbl protein was detectable in brain, heart, kidney, intestine, muscle, lung, and testis. An assay for GEF activity revealed that the var.2 exhibits decreased GEF activity towards Cdc42, var.3 exhibits a weak but significant activity toward Rac1 and Cdc42, var.4 exhibits significant activity toward RhoA and Cdc42, while var.1 exhibits no activity toward RhoA, Rac1, or Cdc42. In summary, we describe 4 splicing variants of the human DBL proto-oncogene that show different tissue distributions and GEF specificities.  相似文献   

14.
新变种上犹杜鹃的ITS分子标记证据分析   总被引:2,自引:0,他引:2  
对杜鹃花科杜鹃属的新变种上犹杜鹃进行了ITS分子标记分析。结果表明:(1)上犹杜鹃与原变种毛果杜鹃在系统树上没有聚合为一支;(2)上犹杜鹃ITS序列密码子第二位上的G+C含量与原变种毛果杜鹃差异明显,而且编码位上的G+C含量(G+Cc)也与原变种毛果杜鹃有差异;(3)上犹杜鹃与原变种毛果杜鹃的形态特征有明显的区别,并具间断性特征;(4)密码子偏向性指数CBI分析正好反映了上犹杜鹃处于"变种"等级阶段的特点。基于这些证据,认为上犹杜鹃处理为种以下等级"变种"比较合理。  相似文献   

15.
The spread of cucumber mosaic virus (CMV) was followed during three years in field plots of bell pepper varieties Yolo Wonder (susceptible) and Milord and Vania (partially resistant to CMV movement within plants). During the three test years, CMV spread was delayed 4 to 6 weeks in var. Milord and in var. Vania as compared to var. Yolo Wonder. Final CMV incidence and the apparent infection rate, the latter calculated from Van der Plank logistic analyses, were lower in var. Milord and in var. Vania than in var. Yolo Wonder. The resistance of var. Milord and var. Vania, expressed as a delay of spread and a reduced CMV incidence over the past three years, provides practical disease control.  相似文献   

16.
中国西南地区杨属的分类学研究(Ⅰ)   总被引:1,自引:0,他引:1  
本文包括:康定杨的补充记载,4个新组合,16个新异名,2个天然杂种,2个分布新记录,2个新变种。  相似文献   

17.
BACKGROUND: and Aims The four cultivated Erythroxylum taxa (E. coca var. coca, E. novogranatense var. novogranatense, E. coca var. ipadu and E. novogranatense var. truxillense) are indigenous to the Andean region of South America and have been cultivated for folk-medicine and, within the last century, for illicit cocaine production. The objective of this research was to assess the structure of genetic diversity within and among the four cultivated alkaloid-bearing taxa of Erythroxylum in the living collection at Beltsville Agricultural Research Center. METHODS: Amplified fragment length polymorphism (AFLP) fingerprinting was performed in 86 Erythroxylum accessions using a capillary genotyping system. Cluster analysis, multidimensional scaling (MDS) and analysis of molecular variance (AMOVA) were used to assess the pattern and level of genetic variation among and within the taxa. KEY RESULTS: A clear distinction was revealed between E. coca and E. novogranatense. At the intra-specific level, significant differentiation was observed between E. c. var. coca and E. c. var. ipadu, but the differentiation between E. n. var. novogranatense and E. n. var. truxillense was negligible. Erythroxylum c. var. ipadu had a significantly lower amount of diversity than the E. c. var. coca and is genetically different from the E. c. var. ipadu currently under cultivation in Colombia, South America. CONCLUSIONS: There is a heterogeneous genetic structure among the cultivated Erythroxylum taxa where E. coca and E. novogranatense are two independent species. Erythroxylum coca var. coca is most likely the ancestral taxon of E. c. var. ipadu and a founder effect may have occurred as E. c. var. ipadu moved from the eastern Andes in Peru and Bolivia into the lowland Amazonian basin. There is an indication of artificial hybridization in coca grown in Colombia.  相似文献   

18.
A key is provided for Andropogon and the segregate genera, Schizachyrium, Bothriochloa, and Dichanthium, as represented in the United States. Included also is a listing of the native and introduced species of each: 17 species of Andropogon (all native) ; 11 species of Schizachryium (all native) ; 14 species of Bothriochloa (8 native + 6 introduced) ; 3 species of Dichanthium (all introduced). New combinations are proposed for: Schizachryium niveum; S. rhizomatum; S. sericatum; S. scoparium var. divergens, var. frequens, var. littoralis, var. neomexicanum, and var. virile.  相似文献   

19.
Summary Several mutants that enhance the gene inactivation associated with position-effect variegation [E(var) mutants] have been characterized. These include three ethyl methanesulfonate (EMS)-induced lesions and a second chromosome duplication. Each of the EMS mutations maps to a discrete euchromatic site on the third chromosome. One is located within the chromosomal region occupied by a cluster of Su(var) mutations. All four E(var) mutants enhance the inactivation of several different variegators and therefore they appear to influence position-effect variegation generally. However, the enhancement caused by the single site E(var) mutations is less striking than that caused by the duplication or by loss of the Y chromosome. The interaction between the E(var) mutants and selected Su(var) mutations, as well as the effects of extra Y heterochromatin on E(var) expression, have also been investigated. Based on the results of these studies, various hypothetical functions of the E(var) + products are suggested.  相似文献   

20.
Bromus setifolius var. pictus (Hook) Skottsb., B. setifolius var. setifolius Presl. and B.setifolius var. brevifolius Ness are three native Patagonian taxa in the section Pnigma Dumort of the genus Bromus L. AFLP and RAPD analysis, in conjunction with genetic distance measurements and statistical techniques, revealed variation within this group and indicated that B. setifolius var. brevifolius was closely related to B. setifolius var. pictus, with both taxa being more distantly related to B. setifolius var. setifolius. Cytogenetic analysis confirmed the chromosomal number of B. setifolius var. pictus (2n = 70) and B. setifolius var. setifolius (2n = 28) and showed for the first time that B. setifolius var. brevifolius had 2n = 70. The combination of molecular genetic and cytogenetic evidence supported a species status for two of the three taxa and suggested hypotheses for the evolutionary origin of these complex taxa. Species status was also indicated for B. setifolius var. setifolius. Based on these findings, we suggest that B. setifolius var. pictus be referred to as B. pictus Hook var. pictus, and B. setifolius var brevifolius as B. pictus Hook var brevifolius. The correlation between AFLP diversity and variation in ecological parameters suggested that this marker system could be used to assess breeding progress and to monitor the domestication of Patagonian Bromus species for agronomic use.  相似文献   

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