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1.
Callus and suspension cultures derived from leaf explants of Plumbago rosea were established and plumbagin, a naphthoquinone, was isolated from them and confirmed by 1H NMR and electron-ionization mass spectroscopy. Maximum content of plumbagin was obtained in the stationary phase of growth (4.3 mg g–1 dry cell wt). Media pH, phytohormones and carbon sources were optimized for biomass and plumbagin accumulation. Cell aggregates, measuring 500 m in diam, produced 8.2 g dry cell wt l–1, but larger aggregates (above 500 m) favored plumbagin accumulation with an yield of 4.5 mg g–1 dry cell wt.  相似文献   

2.
Thirty-four species of the genus Plectranthus (including species of the former genera Coleus and Solenostemon, fam. Lamiaceae) were surveyed for exudate flavonoids to see whether the distribution of these compounds would support a recent classification of the genus based on molecular and morphological characters. In this classification two major groups had been identified, the Coleus and Plectranthus clades. Only about 40% of the species, predominantly from the Plectranthus clade, were found to produce exudate flavonoids, which were mainly flavones. Flavanones were restricted to five species of the Plectranthus clade, whereas flavonols were only found in two species of the Coleus clade, Plectranthus montanus Benth. (synonyms Plectranthus marrubioides Hochst. ex Benth. and Plectranthus cylindraceus Hochst. ex Benth.) and Plectranthus pseudomarrubioides R.H.Willemse. Four of these flavonols were isolated from P. montanus and identified by NMR spectroscopy as the 3,7-dimethyl ether and 3,7,4′-trimethyl ether of quercetin and the 3,6,7-trimethyl ether and 3,6,7,4′-tetramethyl ether of quercetagetin. The remaining flavonols and flavones were identified by HPLC–UV and LC–MS of crude extracts on the basis of their UV and mass spectra, retention times and comparison with standards. Most flavonols were 3-methyl ethers and many of the flavones and flavonols were oxygenated at the 6-position. The most common flavones, occurring in both clades, were cirsimaritin and salvigenin, which are methoxylated at the 6- and 7-positions. 6-Hydroxylated flavones such as scutellarein and ladanein were restricted to species of the Plectranthus clade.  相似文献   

3.
The microsporidian species, Nosema apis and Nosema ceranae are both known to infect the European honeybee, Apis mellifera. Nosema disease has a global distribution and is responsible for considerable economic losses among apiculturists. In this study, 336 honeybee samples from 18 different prefectures in Japan were examined for the presence of N. apis and N. ceranae using a PCR technique. Although N. ceranae was not detected in most of the apiaries surveyed, the parasite was detected at three of the sites examined. Further, N. ceranae appears to be patchily distributed across Japan and no apparent geographic difference was observed among the areas surveyed. In addition, the apparent absence of N. apis suggests that N. ceranae may be displacing N. apis in A. mellifera in Japan. Partial SSU rRNA gene sequence analysis revealed the possible existence of two N. ceranae groups from different geographic regions in Japan. It seems likely that these microsporidian parasites were introduced into Japan through the importation of either contaminated honeybee-related products or infected queens. This study confirmed that PCR detection is effective for indicating the presence of this pathogen in seemingly healthy colonies. It is therefore hoped that the results presented here will improve our understanding of the epidemiology of Nosema disease so that effective controls can be implemented.  相似文献   

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When administered to rats, echitamine was absorbed rapidly from the tissues and was detected in circulation within 30 min. The drug level reached a maximum value by 2 h and then decreased steadily. The drug had completely disappeared from the blood in 6 h. The presence of echitamine was observed within 2 h in urine and the maximum amount of drug was excreted between 2 and 4 h. About 90% of the drug was excreted in urine in 24 h and the drug could not be detected in urine after 48 h. Along with echitamine, its metabolites were also detected in the urine. Plumbagin was not detected in blood upto 24 h when administered into rats. The drug was detected in urine within 4 h after administration; a major portion of the drug was excreted in urine by 24 h and traces of the drug were observed in the urine even after 48 h.  相似文献   

6.
Capparis ovata var. palaestina Zoh., C. spinosa var. aegyptia Boiss. and C. spinosa var. deserti Zoh., were investigated for glucosinolates. Glucoiberin, glucocapparin, sinigrin, glucocleomin, glucocapangulin, glucobrassicin and neoglucobrassicin, in addition to two others, were isolated. Four of these viz. glucoiberin, sinigrin, glucobrassicin and neoglucobrassicin were detected for the first time in Capparis species. Comparative chromatographic analyses of the glucosinolates of the plants examined revealed qualitative differences.  相似文献   

7.
Invasive ascidians are a growing concern for ecologists and natural resource managers, yet few studies have documented their short- and long-term temporal patterns of abundance. This study focuses on the invasion of the Gulf of Maine by the colonial ascidians Botryllus schlosseri, Botrylloides violaceus, Diplosoma listerianum and Didemnum sp. A. We examined the time of arrival and potential vectors for these four invasive ascidians using survey data (collected from 1969 onwards) and literature documentation. We also compared the dominance and seasonal patterns of abundance of these species using data from two identical panel studies; one conducted from 1979 to 1980, the other from 2003 to 2005. Didemnum and Botrylloides were most likely first introduced into the Damariscotta River, Maine in the early 1970's through oyster aquaculture while Botryllus and Diplosoma were probably transported by commercial and recreational vessels. The overall abundance of colonial ascidians has increased since 1979 and 1980. Botryllus was the only invasive colonial ascidian present during the 1979 to 1980 study and accounted for an average of 6.16% cover on panels. From 2003 to 2005, the more recently arrived colonial ascidians Botrylloides and Didemnum accounted for 7.38% and 2.08% cover respectively, while Botryllus covered only 1.16%. Our results reveal a shift in seasonal abundance between 1979 to 1980 and 2003 to 2004. In 1979 and 1980, colonial ascidians had the highest percent cover in fall and winter while in 2003 and 2005 they had highest percent cover in summer and fall. Seasonal patterns of space occupation by colonial ascidians were correlated with seasonal changes in seawater temperature.  相似文献   

8.
Avian species are commonly infected by multiple parasites, however few studies have investigated the environmental determinants of the prevalence of co-infection over a large scale. Here we believe that we report the first, detailed ecological study of the prevalence, diversity and co-infections of four avian blood-borne parasite genera: Plasmodium spp., Haemoproteus spp., Leucocytozoon spp. and Trypanosoma spp. We collected blood samples from 47 resident and migratory bird species across a latitudinal gradient in Alaska. From the patterns observed at collection sites, random forest models were used to provide evidence of associations between bioclimatic conditions and the prevalence of parasite co-infection distribution. Molecular screening revealed a higher prevalence of haematozoa (53%) in Alaska than previously reported. Leucocytozoons had the highest diversity, prevalence and prevalence of co-infection. Leucocytozoon prevalence (35%) positively correlated with Trypanosoma prevalence (11%), negatively correlated with Haemoproteus prevalence (14%) and had no correlation with Plasmodium prevalence (7%). We found temperature, precipitation and tree cover to be the primary environmental drivers that show a relationship with the prevalence of co-infection. The results provide insight into the impacts of bioclimatic drivers on parasite ecology and intra-host interactions, and have implications for the study of infectious diseases in rapidly changing environments.  相似文献   

9.
The rapid clonal multiplication of two species of South African Drosera is described. Levels of plumbagin, (5-hydroxy-2-methyl-1,4-naphthoquinone) from in vivo and in vitro grown plants are compared to those present in Plumbago roots. P. auriculata Lam. roots contained more than twice as much plumbagin as in vivo grown D. capensis L. plants which in turn contained more than twice as much as comparable plants of D. natalensis Diels. It is concluded that the extraction of plumbagin from Drosera plants is not commercially feasible.  相似文献   

10.
杜泽乡 《广西植物》2012,32(3):424-426
采用高效液相色谱法(HPLC),对桂林产的白花丹茎中不同月份的白花丹醌含量进行了测定。结果表明:在流动相为甲醇-水(70:30),检测波长为254nm的条件下,白花丹醌在0.00048~0.0240mg.mL-1之间线性关系良好;回收率为96.9%~100.0%,白花丹茎中白花丹醌含量10月份最高,这时也是白花丹茎生物产量的高峰期,说明10月份是白花丹茎的最佳采收期。  相似文献   

11.
Entomopathogenic nematodes (EPNs) distribution in natural areas and crop field edges in La Rioja (Northern Spain) has been studied taking into account environmental and physical-chemical soil factors. Five hundred soil samples from 100 sites of the most representative habitats were assayed for the presence of EPNs. The occurrence of EPNs statistically fitted to a negative binomial distribution, which pointed out that the natural distribution of these nematodes in La Rioja was in aggregates. There were no statistical differences (p < or = 0.05) in the abundance of EPNs to environmental and physical-chemical variables, although, there were statistical differences in the altitude, annual mean air temperature and rainfall, potential vegetation series and moisture percentage recovery frequency. Twenty-seven samples from 14 sites were positive for EPNs. From these samples, twenty isolates were identified to a species level and fifteen strains were selected: 11 Steinernema feltiae, two S. carpocapsae and two S. kraussei strains. S. kraussei was isolated from humid soils of cool and high altitude habitats and S. carpocapsae was found to occur in heavy soils of dry and temperate habitats. S. feltiae was the most common species with a wide range of altitude, temperature, rainfall, pH and soil moisture, although this species preferred sandy soils. The virulence of nematode strains were assessed using G. mellonella as insect host, recording the larval mortality percentage and the time to insect die, as well as the number of infective juveniles produced to evaluate the reproductive potential and the time tooks to leave the insect cadaver to determinate the infection cycle length. The ecological trends and biological results are discussed in relationship with their future use as biological control.  相似文献   

12.
The Fibrobacteres phylum contains two described species, Fibrobacter succinogenes and Fibrobacter intestinalis, both of which are prolific degraders of cellulosic plant biomass in the herbivore gut. However, recent 16S rRNA gene sequencing studies have identified novel Fibrobacteres in landfill sites, freshwater lakes and the termite hindgut, suggesting that members of the Fibrobacteres occupy a broader ecological range than previously appreciated. In this study, the ecology and diversity of Fibrobacteres was evaluated in 64 samples from contrasting environments where cellulose degradation occurred. Fibrobacters were detected in 23 of the 64 samples using Fibrobacter genus-specific 16S rRNA gene PCR, which provided their first targeted detection in marine and estuarine sediments, cryoconite from Arctic glaciers, as well as a broader range of environmental samples. To determine the phylogenetic diversity of the Fibrobacteres phylum, Fibrobacter-specific 16S rRNA gene clone libraries derived from 17 samples were sequenced (384 clones) and compared with all available Fibrobacteres sequences in the Ribosomal Database Project repository. Phylogenetic analysis revealed 63 lineages of Fibrobacteres (95% OTUs), with many representing as yet unclassified species. Of these, 24 OTUs were exclusively comprised of fibrobacters derived from environmental (non-gut) samples, 17 were exclusive to the mammalian gut, 15 to the termite hindgut, and 7 comprised both environmental and mammalian strains, thus establishing Fibrobacter spp. as indigenous members of microbial communities beyond the gut ecosystem. The data highlighted significant taxonomic and ecological diversity within the Fibrobacteres, a phylum circumscribed by potent cellulolytic activity, suggesting considerable functional importance in the conversion of lignocellulosic biomass in the biosphere.  相似文献   

13.
Nectaries in leaves of Gentianaceae have been poorly studied. The present study aims to describe the distribution, anatomy, and ecological aspects of extrafloral nectaries (EFNs) of three Calolisianthus species and in particular the ultrastructure of EFNs in Calolisianthus speciosus during leaf development, discussing its unusual structure. Leaves of Calolisianthus species were fixed and processed by the usual methods for studies using light, scanning microscopy and transmission electron microscopy (TEM). Ion chromatography was used to analyze the nectar exudates of C. speciosus. The distribution patterns of nectar secretion units were analysed by ANOVA and t-tests. Two EFNs that can be seen macroscopically were observed at the bases of C. speciosus and C. pendulus leaves. Such large nectaries are absent there in C. amplissimus. Another similarly large EFN is observed at the apex of each leaf in all species. The EFNs at the base of the young leaves in C. speciosus are visited by ants during the rainy season. EFNs are formed by several nectar secretory units (nectarioles) that are present throughout the leaves. Each nectariole is formed by rosette cells with a central channel from which the nectar is released. Channels of old C. speciosus and C. pendulus EFNs were obstructed by fungi. TEM of EFNs in young leaves showed cytoplasms with secretion, small vacuoles, mitochondria, cell wall ingrowth, and plasmodesmata. TEM of EFNs in old leaves demonstrated dictyosomes, plastids, mitochondria, segments of endoplasmatic reticulum, and lipid droplets. The nectar contains sucrose, glucose and fructose.  相似文献   

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Differential bacterial counts were made on the intestinal and caecal contents of chickens after inoculation with a standard dose of 320 000 freshly sporulated oocysts of Eimeria brunetti.  相似文献   

17.
Antennapedia is one of the homeotic selector genes required for specification of segment identity in Drosophila. Dominant mutations that ectopically express Antennapedia cause transformation of antenna to leg. Loss-of-function mutations cause partial transformation of leg to antenna. Here we examine the role of Antennapedia in the establishment of leg identity in light of recent advances in our understanding of antennal development. In Antennapedia mutant clones in the leg disc, Homothorax and Distal-less are coexpressed and act via spineless to transform proximal femur to antenna. Antennapedia is negatively regulated during leg development by Distal-less, spineless, and dachshund and this reduced Antennapedia expression is needed for the proper development of distal leg elements. These findings suggest that the temporal and spatial regulation of the homeotic selector gene Antennapedia in the leg disc is necessary for normal leg development in Drosophila.  相似文献   

18.
The sterols and triterpenoids of 12 species of the genus Ononis were analysed by GLC. α-Onocerin was found in all but one of these species, although in some others its concentration was low. In all species examined, sitosterol was the major sterol; stigmasterol, campesterol, cholesterol and the triterpenoids cycloartenol and 24-methylene cycloartanol also occurred. The patterns of α-onocerin and sterols found seem to be consistent with the accepted classification of species within the genus.  相似文献   

19.
Toxicity of two plumbaginoids viz., plumbagin and juglone to the eggs of the cotton stainer,Dysdercus koenigii was studied by a residual film technique. Of these two, plumbagin showed the higher toxicity against different-age eggs with LC50 ranging from 0.0044 to 0.0066%. Eggs showed low susceptibility in the middle of embryogenesis. The toxicity of plumbaginoids, especially plumbagin, is discussed in relation to mode of action and prospects of its use as an ovicide in control of the insect.  相似文献   

20.
Lin LC  Yang LL  Chou CJ 《Phytochemistry》2003,62(4):619-622
Two plumbagic acid glucosides, 3'-O-beta-glucopyranosyl plumbagic acid and 3'-O-beta-glucopyranosyl plumbagic acid methylester along with five naphthoquinones (plumbagin, chitranone, maritinone, elliptinone and isoshinanolone), and five coumarins (seselin, 5-methoxyseselin, suberosin, xanthyletin and xanthoxyletin) were isolated from the roots of Plumbago zeylanica. All coumarins were not previously found in this plant. Cytotoxicity of these compounds to various tumor cells lines was evaluated, and plumbagin significantly suppressed growth of Raji, Calu-1, HeLa, and Wish tumor cell lines.  相似文献   

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