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He Meng Guoyu Li Ronghua Dai Yuepin Ma Ke Zhang Cui Zhang Xian Li Jinhui Wang 《Biochemical Systematics and Ecology》2010,38(6):1220-1223
Phytochemical investigations of the rhizomes of Atractylodes chinensis (DC.) Koidz. resulted in the isolation of four sesquiterpenes (1–4), five polyacetylenes (5–9), oleanolic acid (10), and 5-hydromethyl furaldehyde (11). Among them, seven compounds (3, 5–10) were firstly isolated from the A. chinensis, and all have been reported in the genus Atractylodes except compound 10. The chemotaxonomic significance of these compounds was summarized. 相似文献
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Xiaodong Jiang Guizhong Wang Shaojing Li 《Journal of experimental marine biology and ecology》2004,312(1):89-100
The distribution and abundance of viable resting eggs of copepod Acartia pacifica in Xiamen Bay, China, were determined in the laboratory by the presence of nauplii hatched from the sediments. Sediment cores to a depth of 30 cm, sliced at 1.0 cm intervals, showed that most viable resting eggs of A. pacifica occurred near the sediment surface (0-5 cm), and the number of viable eggs sharply decreased with depth of the sediment, although resting eggs remained viable as deep as 23 cm. 210Pb analyses of the sediments indicated that the maximum age of viable eggs of A. pacifica was 20.5 years and the mean egg age was 4.3 years. The egg mortality of A. pacifica in the sediment was 0.1408 year−1, or 85.92% annual egg survival, calculated by regressing ln(egg density) on the age of the sediment. The horizontal distribution of viable resting eggs ranged from 2.27×103 to 3.85×105 m−2, with a mean value of 9.49×104 m−2. Regressions between viable eggs of A. pacifica and all fine-fraction particle size classes (at 2 μm intervals) were not significant. The accumulation of viable resting eggs that can persist for an extended period of time provided evidence for the existence of an egg bank of A. pacifica in the seabed of Xiamen Bay. 相似文献
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Zhi-Qiang Du Qian Ren Xiao-Fan Zhao Jin-Xing Wang 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2009,154(2):203-210
The whey major component, whey acidic protein (WAP), has one or more WAP domains characterized by a four-disulfide core (4-DSC) structure. These kinds of proteins are involved in multiple functions, including proteinase inhibitor activity, antimicrobial activity, ATPase inhibitor activity, and regulatory function in cell proliferation. Recent research indicates that WAP domain-containing proteins play an important role in the innate immunity of crustaceans. In this study, a novel double WAP domain (DWD)-containing protein named Fc-DWD was found for the first time in Chinese white shrimp, Fenneropenaeus chinensis. The open reading frame of Fc-DWD encodes a protein of 117 amino acids, including a signal peptide of 16 amino acids and two WAP domains. The predicted molecular mass of the mature protein is 12.78 kDa with an estimated pI of 8.49. The first WAP domain, named WAP 1, composed of 49 amino acids locates in the amino-terminal of Fc-DWD, and the second WAP domain, named WAP 2, composed of 45 amino acids locates in the carboxy-terminal. Fc-DWD mRNA was upregulated in hemocytes, hepatopancreas, gills, and stomach of bacteria- and virus-challenged shrimp. Results of the binding assay showed that rFc-DWD could bind to both Gram-negative bacteria and Gram-positive bacteria. rWAP 1 could only bind to Gram-positive bacteria, but rWAP 2 could bind to both Gram-negative and positive bacteria. Moreover, rFc-DWD exhibited proteinase inhibitory activity against the secretory proteinase(s) from Bacillus subtilis and Pseudomonas aeruginosa. All of these findings suggest that Fc-DWD may play an important role in enabling the host defense to execute its proteinase inhibitory activity against pathogens. 相似文献
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Zhumei Ren Enbo Ma Yaping Guo 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2002,520(1-2):141-150
Chromosome aberrations induced by an anti-neoplastic drug, cyclophosphamide (CP) and a bioinsecticide, Bacillus thuringiensis (B.t.) were examined using grasshoppers as an animal model, with injection as the route of exposure. Oxya chinensis (Thunberg), having a small number (2n♂=23) of large-sized chromosomes in males, was used for this purpose. The fifth instar nymphs were treated with various concentrations of CP (2, 5 and 10 mg/ml) and B.t. (0.55, 1.83 and 5.50 IU/ml) by injection into the abdomen, using physiological saline and distilled water as negative controls, respectively. The chromosomal preparations were made from the spermatogonia of the specimen testis at different intervals after dosing (24 and 48 h). The effect of the high dose of CP (10 mg/ml) in O. chinensis was also analyzed at the 42-h time point. The chromosome aberrations observed were mainly chromatid and chromosome breaks. CP induced a dose- and time-dependents increase in the number of chromosome aberrations (CAs) per cell and in the percentage of aberrant cells. The strongest effect was seen when grasshoppers were injected with the highest dose and cells were analyzed at the 48-h time point. The results show that CP induced a significant increase in the frequency of CAs in testicular cells of O. chinensis with the three doses employed, compared to the negative control. Our results suggest that there exists in the grasshopper an enzyme system analogous to liver-S9 fraction, and that CP may be used as a positive control in genotoxicity test in this species. In addition, the evaluation of the chromosome aberrations induced by B.t. in the grasshoppers’ testicular cells showed that B.t. may induce chromosome aberrations, mainly chromatid and chromosome breaks, in spermatogonia. By statistical analysis, B.t. showed significant dose–effect relationships and it may be mutagenic in this species. Recent research has focused on the development of biological insecticides to protect cereal crops against damage by insect species, such as beetles and grasshoppers. The present studies may contribute to our knowledge of entomological genotoxicity in grasshoppers and provide reference for the research on the mechanism of B.t. toxicity. 相似文献
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The new genus and species Teracosphaeria petroica is described for a perithecial ascomycete and its anamorph occurring on decayed wood collected in New Zealand. The fungus produces immersed, non-stromatic ceratosphaeria-like perithecia in nature, with hyaline, septate ascospores produced in unitunicate, non-amyloid asci. The anamorph produced in vitro is phialophora-like with lightly pigmented phialides terminating in flaring, deep collarettes that are often noticeably brown with conspicuous periclinal thickening. Phylogenetic analysis of LSU rDNA sequence data indicates that this fungus is distinct from morphologically similar fungi classified in the Chaetosphaeriales, the Trichosphaeriales or the Magnaporthaceae. It forms a monophyletic group with recently described, chaetosphaeria-like ascomycetes, such as the pyrenomycete genus Mirannulata, and shows affinity with the anamorphic species Dictyochaeta cylindrospora. The usefulness of describing anamorph genera for morphologically reduced anamorphs, when anamorph characteristics are actually part of the holomorph diagnosis, is discussed. An apparently contradictory example of the so-called Cordana and Pseudobotrytis anamorphs of Porosphaerella spp. is also discussed. 相似文献
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The fungal Rhizopus chinensis could produce several types of lipase, which were mainly intracellular. During the whole-cell lipase production by this strain in submerged fermentation, it was observed that two catalytic characteristics (hydrolytic and synthetic activity) of lipases were different with addition of lipids. The hydrolytic activity of the lipase was not induced by lipids efficaciously and could be detected regardless of whether substrate-related compounds were present. However, it was found that the induction of lipids for the synthetic activity lipase was significant, and that nearly no synthetic activity was detected while the medium contained no lipids. When only a little lipid (1 g/L) was added to medium, the synthetic activity increased sharply in the initial process of fermentation. Analysis of crude membrane-bound lipase by SDS-PAGE confirmed this induction. De novo biosynthesis of lipases, especially the lipase with synthetic activity occurred only when lipids existed. Cell growth and maltose repress the lipase production with synthetic activity, but have little influence on the lipase production with hydrolytic activity. Since the production process of mycelium-bound lipase with hydrolytic activity was different, it was reasonable to consider hydrolytic activity and synthetic activity for different application purposes. Whole-cell lipase obtained from fermentation process with high synthetic activity showed excellent catalytic ability in solvent free system on synthesis of ethylcaprylate and ethyloleate, the conversion could reach more than 90% in 5 h. 相似文献
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Thadde Boudjeko Christophe Rihouey Denis Omokolo Ndoumou Ismaïl El Hadrami Patrice Lerouge Azeddine Driouich 《Carbohydrate polymers》2009,78(4):820-827
Many Cola plant species are endemic to West and Central Africa. Cola acuminata and Cola nitida are used as masticatory when fresh, while the dried nuts are used for beverages and pharmaceutical purposes in Europe and North America. Garcinia kola seeds, that serve as a substitute for the true kola nuts, are used in African traditional medicine for the treatment of various diseases, including colic, headache and liver cirrhosis. Seeds extracts of G. kola are also known for their anti-inflammatory, antimicrobial and antiviral properties. To gain information on the chemical properties of the kolas, we have isolated and analyzed cell wall polysaccharides, arabinogalactan-proteins and phenolic substances from the seeds of the three kola species. The sugar composition of cell wall material of C. acuminata, C. nitida and G. kola revealed that Gal (up to 30%), Ara, GalA and Glc as the predominant monosaccharides, representing approximately 90% by mol of the total hydrolysable sugar present in this material. In Ammonium oxalate cell wall fraction, GalA was found to be the major sugar present in all kola species. In the alkali-soluble fraction, there were significant differences in the level of Glc and Gal. The level of Glc was high in C. acuminata and C. nitida while the level of Gal and Xyl were high in C. nitida and G. cola. Isolation and quantification of arabinogalactan-proteins demonstrate that G. kola seeds contained four to eight times more of these proteoglycans than the seeds of the other two species. Finally, analysis of soluble phenolic substances shows that caffeine and catechin were largely represented in C. acumina and C. nitida seeds, with caffeine accounting for 50% of all soluble phenolics. These findings indicate that the three Kola seeds are highly enriched in pectins and proteoglycans and that C. acuminata and C. nitida can be used as a possible source of caffeine and catechin. 相似文献
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H. Thorsten Lumbsch Imke Schmitt Robert Lücking Elisabeth Wiklund Mats Wedin 《Mycological Research》2007,111(3):257-267
Results of molecular studies regarding the phylogenetic placement of the order Ostropales and related taxa within Lecanoromycetes were thus far inconclusive. Some analyses placed the order as sister to the rest of Lecanoromycetes, while others inferred a position nested within Lecanoromycetes. We assembled a data set of 101 species including sequences from nuLSU rDNA, mtSSU rDNA, and the nuclear protein-coding RPB1 for each species to examine the cause of incongruencies in previously published phylogenies. MP, minimum evolution, and Bayesian analyses were performed using the combined three-region data set and the single-gene data sets. The position of Ostropales nested in Lecanoromycetes is confirmed in all single-gene and concatenated analyses, and a placement as sister to the rest of Lecanoromycetes is significantly rejected using two independent methods of alternative topology testing. Acarosporales and related taxa (Acarosporaceae group) are basal in Lecanoromycetes. However, if the these basal taxa are excluded from the analyses, Ostropales appear to be sister to the rest of Lecanoromycetes, suggesting different ingroup rooting as the cause for deviating topologies in previously published phylogenies. 相似文献
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Ying-Juan Su Qi-Jie Zan Ting Wang Zhan-Ming Ying Hua-Gu Ye 《Biochemical Systematics and Ecology》2008,36(8):619-625
Apterosperma oblata is a critically endangered Theaceous species endemic to southern China, with only 24 individuals surviving in Ba Jia Zhen, Yangchun, Guangdong province. ISSR markers were used to assess their genetic variation and relationships. Population genetic parameters were estimated by a Bayesian approach as well as conventional methods. Twenty-one primers generated 168 loci, of which 130 (77.38%) were polymorphic. Nei's gene diversity, Shannon's index, and average expected heterozygosity were quantified as 0.2746, 0.4100, and 0.3492, respectively. Compared with other species of Theaceae and its related families, a high level of genetic variation was identified in A. oblata. Cluster analysis using the unweighted pair-group method with arithmetic mean (UPGMA) showed that the 24 individuals mainly fell into three groups of which the grouping of individuals BJZ21, BJZ22, BJZ23, and BJZ24 and their genetic isolation were supported by a principle components analysis (PCA). In addition, molecular bottleneck signatures were revealed in recent population history. In terms of these results, the management and conservation strategy of A. oblata was proposed. 相似文献
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The suitability of Aphis fabae Scopoli, Myzus persicae Sulzer and Aleyrodes proletella L. as food sources for Coccinella undecimpunctata L. was evaluated by studying the impact of prey consumption on the predator’s population growth parameters and feeding parameters. Unlike A. proletella, A. fabae and M. persicae supported the development and reproduction of C. undecimpunctata. A. fabae and M. persicae were considered to be essential prey, whereas A. proletella was considered to be an alternative prey. Aphid species showed different degrees of suitability: M. persicae significantly decreased the pre-oviposition period and increased adult longevity, fecundity and fertility compared with A. fabae. Moreover, A. fabae represents a suitable diet for larval development, but is not a suitable food source for adult reproduction. The predator’s population growth parameters, R0, rm and λ were increased with M. persicae, whereas T decreased. We found that the 4th instar larvae were the most voracious, particularly when fed on M. persicae; nevertheless, with this prey daily weight gain and feeding efficiency of 4th instar larvae were similar to that of individuals fed with A. fabae. 相似文献
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Robert Bauer Berthold Metzler Dominik Begerow Franz Oberwinkler 《Mycological Research》2009,113(9):960-966
A new genus, Cystobasidiopsis, and a new species, Cystobasidiopsis nirenbergiae, are described for a fungus isolated from an arable loess soil in Ahlum near Braunschweig, Niedersachsen, Germany. An integrated analysis of morphological, ecological, ultrastructural and molecular data indicates that the new species belongs to the Chionosphaeraceae within the Agaricostilbales. Relevant characteristics of the new species are discussed and compared with those of related taxa. 相似文献
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Ivna Kocijan Ana Galov Helena ?etkovi? Josip Kusak Tomislav Gomer?i? ?uro Huber 《Mammalian Biology》2011,76(5):615-621
Brown bears have lost most of their range on the European continent. The remaining western populations are small, isolated and highly endangered. The Dinaric-Pindos brown bear population is the western-most stable population and the fourth largest in Europe. It has been recognized as a potential source for recolonization of populations whose survival is at risk. Indeed, several translocations of Dinaric bears to Italy, Austria and France have recently been made. Despite the importance of the Dinaric bear population, its genetic status remains poorly understood. Using tissue samples from 156 hunted or accidentally killed Dinaric bears in Croatia, this study analysed genetic diversity at 12 microsatellite loci, as well as population structure and past reductions in size. In addition, a subset of 59 samples was used to assess diversity of the mitochondrial DNA control region. The results indicate that Dinaric bears have high nuclear genetic diversity, as compared to other extant brown bear populations, despite genetic evidence of a bottleneck caused by past persecutions. However, haplotype diversity was low, probably as a result of male-biased dispersal and female philopatry. Not surprisingly, no evidence of population sub-structure was found using nuclear markers, as the bear habitat has remained continuous and the highway network has been built only recently. Management should focus on maintaining habitat connectivity and keeping the effective population size as large as possible. In addition, when removing individuals, care should be taken not to further deplete the population of rare haplotypes. A coordinated transboundary management of the entire Dinaric-Pindos brown bear population should be a priority for its long-term conservation. 相似文献
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Recent DNA sequence analyses indicated that Nigrosabulum globosum is a cleistothecial representative of the Bionectriaceae in the Hypocreales, but morphological characters supporting this relationship are unknown. Using light and electron microscopy we followed the development of the ascomata of this species, from the formation of gametangia through to the development of mature ascospores, and observed a series of characters that confirmed its hypocrealean affinities. These included the formation of a gel-filled centrum during early stages of ascoma development, the subsequent appearance of hyaline peridial tissue enclosed within a layer we interpret as representing a melanized uniloculate stroma, apically derived paraphyses, and an ascogenous system that gives rise to asci that were both cylindrical to clavate and globose. Ascospores, previously reported to be smooth, were ornamented with a honeycomb-like reticulum and were able to germinate within the ascoma. The carbonaceous outer (stromatic) walls of the mature, grit-like cleistothecia indicate possible resistance to UV radiation and desiccation. Furthermore, the complement of germinated ascospores would enable mature ascomata to function as propagules that could quickly initiate new growth when transferred to fresh substrate. Our reexamination of N. globosum also provides data that support the hypothesized close relationship with other bionectriaceous, cleistothecial coprophiles, i.e., species of Hapsidospora, and Bulbithecium in particular. 相似文献
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Otozamites is a representative fossil leaf morphogenus of the extinct Bennettitales, with an extensive distribution during the Mesozoic, especially in China. Understanding the fossil diversity variation and distribution pattern of Otozamites in China will provide information on biodiversity of bennettitalean plants as well as for reconstruction of palaeogeography and palaeoclimate conditions during the Mesozoic. So far, 46 species of this genus have been described in China, excluding unspecified species. The results show that the fossils of Otozamites are extensively recorded in the Late Triassic, and then reach their maximum development in the Early Jurassic, followed by a reduction in diversity in the Middle and Late Jurassic, and finally become extinct at the end of Early Cretaceous. Geographically, they occur in both Northern and Southern Floristic Provinces in the Mesozoic of China, with a relatively higher abundance in the Southern Floristic Province. It implies that the diversity variation and distribution of Otozamites are closely related to the change of the palaeoclimatic conditions. The warm and humid climate prevailed in the Late Triassic and Early Jurassic in South China, propitious to the development of Otozamites. After the Middle Jurassic, dry and hot climate may have caused the lower diversity level and blocked the development of Otozamites; finally at the end of the Early Cretaceous, the frequent arid climate may be a major cause for the extinction of Otozamites. 相似文献