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1.
Microbiol Spectr ; 12(3): e0340423, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38259091

RESUMO

Arbuscular mycorrhizal fungi (AMF) could establish symbiosis with plant roots, which enhances plant resistance to various stresses, including drought stress and salt stress. Besides AMF, chemical stimulants such as trehalose (Tre) can also play an important role in helping plants alleviate damage of adversity. However, the mechanism of the effect of AMF combined with chemicals on plant stress resistance is unclear. The objective of this study was to explore the synergistic effects of Claroideoglomus etunicatum AMF and exogenous Tre on the antioxidant system, osmoregulation, and resistance-protective substance in plants in response to salt stress. Tomato seedlings were inoculated with Claroideoglomus etunicatum and combined with exogenous Tre in a greenhouse aseptic soil cultivation experiment. We measured the arbuscular mycorrhizal symbiont development, organic matter content, and antioxidant enzyme activity in tomato seedlings. Both AMF and Tre improved the synthesis of chlorophyll content in tomato seedlings; regulated the osmotic substance including soluble sugars, soluble protein, and proline of plants; and increased the activity of superoxide dismutase, peroxidase, and catalase. The combination of AMF and Tre also reduced the accumulation of malondialdehyde and alleviated the damage of harmful substances to plant cells in tomato seedlings. We studied the effects of AMF combined with extraneous Tre on salt tolerance in tomato seedlings, and the results showed that the synergistic treatment of AMF and Tre was more efficient than the effects of AMF inoculation or Tre spraying separately by regulating host substance synthesis, osmosis, and antioxidant enzymes. Our results indicated that the synergistic effects of AMF and Tre increased the plant adaptability against salt damage by enhancing cell osmotic protection and cell antioxidant capacity. IMPORTANCE: AMF improve the plant adaptability to salt resistance by increasing mineral absorption and reducing the damage of saline soil. Trehalose plays an important role in plant response to salt damage by regulating osmotic pressure. Together, the use of AMF and trehalose in tomato seedlings proved efficient in regulating host substance synthesis, osmosis, and antioxidant enzymes. These synergistic effects significantly improved seedling adaptability to salt stress by enhancing cell osmotic protection and cell antioxidant capacity, ultimately reducing losses to crops grown on land where salinization has occurred.


Assuntos
Fungos , Micorrizas , Solanum lycopersicum , Micorrizas/fisiologia , Plântula/microbiologia , Trealose/farmacologia , Antioxidantes/metabolismo , Estresse Salino , Plantas/metabolismo , Solo
2.
Artigo em Inglês | MEDLINE | ID: mdl-37305690

RESUMO

Objective: To explore the role of Huangqin Decoction in intestinal homeostasis maintenance and colon carcinogenesis based on "sterol regulatory element binding protein-1c (SREBP-1)-cholesterol metabolism regulatory T cell (Treg) differentiation." Methods: It was decided to utilize a total of 50 healthy Wistar rats for the study, 20 of which were chosen at random to serve as controls, and 30 of which were used to create an intestinal homeostasis imbalance model. It was determined whether or not the modeling was successful by killing 10 rats from each of the two groups. The remaining 10 rats in the normal group were then employed as the control group for the experiment. The random number table method was used to split the rats into two groups: the Huangqin Decoction (n = 10) and the Natural Recovery (n = 10) groups. For seven days, participants in the Huangqin Decoction group received the herb, whereas those in the natural healing group received normal saline. The relative density of SREBP1, the levels of cholesterol ester (CE), free cholesterol (FC), total cholesterol (TC), and Treg cells were detected and compared. Results: When compared to the control group, the relative density of SREBP1 increased significantly before administration in the Huangqin Decoction group and the natural recovery group, but decreased significantly after administration, with statistical significance (P < 0.05) in the Huangqin Decoction group and the natural recovery group; the Huangqin Decoction group and natural recovery group had significantly higher levels of CE, FC, and TC than the control group before to administration, and these levels increased significantly after administration. CE, FC, and TC levels in Huangqin Decoction and natural recovery groups were much lower than those in natural recovery groups, and the difference was statistically significant (P < 0.05), according to the results; Prior to administration, Treg cell levels in Huangqin Decoction group and the natural recovery group were significantly higher, and Treg cell levels in the Huangqin Decoction group and natural recovery group were significantly lower after administration; the decrease in the Huangqin Decoction group was significantly greater than that in natural recovery group. P < 0.05 indicated that the difference was significant. Conclusion: Using Huangqin Decoction, one may efficiently regulate SREBP1, cholesterol metabolism, and Treg cell development, all of which play an important role in maintaining intestinal stability and minimizing the incidence of colon cancer.

3.
Front Microbiol ; 13: 961815, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992714

RESUMO

The impact of high concentrations of heavy metals and the loss of functional microorganisms usually affect the nitrogen removal process in wastewater treatment systems. In the study, a unique auto-aggregating aerobic denitrifier (Pseudomonas stutzeri strain YC-34) was isolated with potential applications for Cr(VI) biosorption and reduction. The nitrogen removal efficiency and denitrification pathway of the strain were determined by measuring the concentration changes of inorganic nitrogen during the culture of the strain and amplifying key denitrification functional genes. The changes in auto-aggregation index, hydrophobicity index, and extracellular polymeric substances (EPS) characteristic index were used to evaluate the auto-aggregation capacity of the strain. Further studies on the biosorption ability and mechanism of cadmium in the process of denitrification were carried out. The changes in tolerance and adsorption index of cadmium were measured and the micro-characteristic changes on the cell surface were analyzed. The strain exhibited excellent denitrification ability, achieving 90.58% nitrogen removal efficiency with 54 mg/L nitrate-nitrogen as the initial nitrogen source and no accumulation of ammonia and nitrite-nitrogen. Thirty percentage of the initial nitrate-nitrogen was converted to N2, and only a small amount of N2O was produced. The successful amplification of the denitrification functional genes, norS, norB, norR, and nosZ, further suggested a complete denitrification pathway from nitrate to nitrogen. Furthermore, the strain showed efficient aggregation capacity, with the auto-aggregation and hydrophobicity indices reaching 78.4 and 75.5%, respectively. A large amount of protein-containing EPS was produced. In addition, the strain effectively removed 48.75, 46.67, 44.53, and 39.84% of Cr(VI) with the initial concentrations of 3, 5, 7, and 10 mg/L, respectively, from the nitrogen-containing synthetic wastewater. It also could reduce Cr(VI) to the less toxic Cr(III). FTIR measurements and characteristic peak deconvolution analysis demonstrated that the strain had a robust hydrogen-bonded structure with strong intermolecular forces under the stress of high Cr(VI) concentrations. The current results confirm that the novel denitrifier can simultaneously remove nitrogen and chromium and has potential applications in advanced wastewater treatment for the removal of multiple pollutants from sewage.

4.
Artigo em Inglês | MEDLINE | ID: mdl-35482509

RESUMO

Two novel extremely halophilic archaeal strains, designated H27T and FL145T, were isolated from a salt mine and a kelp salt sample, respectively. Cells of both strains were Gram-stain-negative, motile and pleomorphic. The 16S rRNA and rpoB' gene sequence similarities between strains H27T and FL145T were 96.60 and 88.77%. Strains H27T and FL145T were both closely related to Halorhabdus rudnickae WSM-64T, Halorhabdus tiamatea SARL4BT and Halorhabdus utahensis AX-2T, with a 16S rRNA gene sequence similarities of 98.14, 96.34 and 96.27% for strain H27T and 96.42, 95.82 and 96.17% for strain FL145T. The genome-based average nucleotide identity (ANI) values between strains H27T and FL145T, and these three species were 83.93, 79.79 and 79.09% (for strain H27T), and 78.32, 77.95 and 77.05% (for strain FL145T), respectively. The ANI value between strains H27T and FL145T was 78.65 %. The digital DNA-DNA hybridization values between strains H27T and FL145T, and these three species were less than 27.40%, which were below the recommended threshold for membership of the same species. The major polar lipids of both strains were found to consist of sulfated diglycosyl diether, triglycosyl diether, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol. The DNA G+C content was determined from genome to be 62.10 mol% for strain H27T and 61.51 mol% for strain FL145T. Based on phylogenetic, phenotypic, chemotaxonomic and genomic analyses, these two new isolates should be classified as representing two novel species in the genus Halorhabdus, with strain H27T (=CGMCC 1.16342T=NBRC 113589T) as the type strain of a new species for which we propose the name Halorhabdus amylolytica sp. nov., and strain FL145T (=CGMCC 1.13888T=NBRC 114260T) as the type strain of another new species for which we propose the name Halorhabdus salina sp. nov.


Assuntos
Artrópodes , Ácidos Graxos , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Arqueal/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Halobacteriaceae , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
5.
Front Genet ; 12: 798587, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069696

RESUMO

Non-small cell lung cancer remains the leading cause of cancer-related deaths worldwide with high morbidity and mortality. There is an urgent need to reveal new molecular mechanisms that contribute to NSCLC progression to facilitate drug development and to improve overall survival. Much attention has been paid to the role of circRNAs in NSCLC development. However, the knowledge of circRNAs in NSCLC is still limited, and need to be further explored. The dysregulation of circACC1 was evaluated by qRT-PCR in NSCLC samples and cell lines. The oncogenic role of circACC1 in NSCLC progression was analyzed by CCK8 and colony formation assays. The interaction between the circACC1 and miR-29c-3p, as well as MCL-1, was verified by qRT-PCR, Western blot, luciferase reporter assay, and RIP experiment. Elevated levels of circACC1 were found in NSCLC patients and were negatively correlated with OS. Ectopic expression of circACC1 promoted the capacity of cell growth and clonogenicity, while the inhibition of circACC1 decreased the proliferation and clonogenicity potential. Mechanism studies elucidated that circACC1 contributes to cell growth via directly binding to miR-29c-3p. Transfection of miR-29c-3p mimic blocked circACC1 mediated NSCLC cell proliferation. MCL-1 is a downstream target of miR-29c-3p in NSCLC cells. The circACC1/miR-29c-3p/MCL-1 axis is important in NSCLS proliferation.

6.
Drug Deliv ; 26(1): 499-508, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31033359

RESUMO

In this paper, the self-assembled folate-biotin-quaternized starch nanoparticles (FBqS NPs) were used as carrier system of doxorubicin (DOX) and siRNAIGF1R for the codelivery of both into human lung adenocarcinoma cell lines (A549 cells) in vitro. The cytotoxicity, targeted ligand competition, cell proliferation inhibition, cellular uptake, endocytosis mechanism and target protein suppression of drug-loaded FBqS NPs were evaluated in detail. Compared with several other drug formulations under same condition, siRNAIGF1R/DOX/FBqS NPs exhibited the greatest cytotoxicity to A549 cells and the cytotoxicity was competitively inhibited by free folate in dose-dependent manner. The A549 cells treated by siRNAIGF1R/DOX/FBqS NPs showed the lowest cell proliferation capacity. The energy-dependent clathrin- and caveolae-mediated endocytosis might be the primary cellular uptake mechanism of drug-loaded FBqS NPs. The expression of IGF1R protein in A549 cells treated by siRNAIGF1R/FBqS NPs declined dramatically. So the FBqS NPs were expected as the co-carrier system of chemotherapeutants and siRNAs for future clinical application.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Nanopartículas/química , RNA Interferente Pequeno/administração & dosagem , Células A549 , Antineoplásicos/farmacologia , Biotina/química , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Endocitose/efeitos dos fármacos , Ácido Fólico/química , Humanos , Neoplasias Pulmonares/patologia , Tamanho da Partícula , RNA Interferente Pequeno/farmacologia , Amido/química
7.
Curr Microbiol ; 76(1): 52-56, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30317405

RESUMO

An extremely halophilic archaeon, strain ZY8T, was isolated from a rock salt of Yunnan salt mine. It was able to grow at 12-30% (w/v) NaCl (optimum, 15-20%), pH 7.0-9.0 (optimum, pH 8.5), and 20-45 °C (optimum, 42 °C). Sequence similarity search of its 16S rRNA gene showed that strain ZY8T belonged to the genus Halorubrum, and it is closely related to species of H. aethiopicum SAH-A6T (98.6%), H. aquaticum EN-2T (98.6%), and H. halodurans Cb34T (98.5%), respectively. Strain ZY8T contained phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate as its major phospholipids, and a sulfated diglycosyl diether as its major glycolipid. The DNA G+C content was 66.7 mol%. DNA-DNA relatedness between strains ZY8T and closely related species were far below 70%. Based on the phenotypic and phylogenetic analyses, it is proposed that strain ZY8T represents a novel species of the genus Halorubrum, for which the name Halorubrum glutamatedens sp. nov. is proposed. The type strain is ZY8T (=CGMCC 1.16026T=NBRC 112866T).


Assuntos
Halorubrum , Cloreto de Sódio/análise , Composição de Bases/genética , DNA Arqueal/genética , Halorubrum/classificação , Halorubrum/genética , Halorubrum/crescimento & desenvolvimento , Halorubrum/isolamento & purificação , Mineração , Fosfolipídeos/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
8.
Artif Cells Nanomed Biotechnol ; 46(sup3): S774-S782, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30280608

RESUMO

In this paper, a new oral insulin formulation, insulin-loaded carboxymethyl-ß-cyclodextrin-grafted chitosan nanoparticles (insulin/CMCD-g-CS NPs), was fabricated by ionic crosslinking technique. The therapeutic efficacy of new formulation was investigated in detail. Firstly, the CMCD-g-CS was synthesized by EDC-mediated esterification reaction. The prepared CMCD-g-CS exhibited favourable loading capacity and encapsulation efficiency of drug. The release experiment in vitro showed that the nanocarrier could efficiently protect encapsulated insulin at simulated gastric environment and release drug in the simulated colonic fluid. The insulin/CMCD-g-CS NPs effectively promoted drug internalization into Caco-2 cells and could reversibly open the tight junction between cells. The oral administration of insulin/CMCD-g-CS NPs could lastingly decrease blood sugar level in diabetic mice. The liver function study verified that the insulin/CMCD-g-CS NPs had not obvious toxicity to experimental mice. Therefore, the CMCD-g-CS could be an effective and safe oral insulin delivery carrier for future clinical application. A new biocompatible polysaccharide nanoparticle was fabricated as oral insulin delivery carrier for improving diabetic treatment.


Assuntos
Quitosana , Diabetes Mellitus Experimental , Portadores de Fármacos , Insulina , beta-Ciclodextrinas , Administração Oral , Animais , Células CACO-2 , Quitosana/química , Quitosana/farmacocinética , Quitosana/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Liberação Controlada de Fármacos , Humanos , Insulina/química , Insulina/farmacocinética , Insulina/farmacologia , Masculino , Camundongos , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacocinética , beta-Ciclodextrinas/farmacologia
9.
Int J Syst Evol Microbiol ; 67(10): 4266-4271, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28920842

RESUMO

Gram-negative, spiral or curved rod-shaped cells of a bacterial strain, designated ZC80T, were isolated from a rock salt sample collected at Yunnan salt mine, China. Analysis of the strain's 16S rRNA gene sequence revealed a clear affiliation of this novel strain within the family Rhodospirillaceae. Strain ZC80T formed a robust cluster with Pelagibius litoralis CL-UU02T at a 16S rRNA gene sequence similarity level of 88.1 %. Strain ZC80T shared no more than 91.0 % 16S rRNA gene sequence similarity with the type strains of other species in the family Rhodospirillaceae. Strain ZC80T was able to grow in the presence of 2-15 % (w/v) NaCl, and grew at 10-50 °C and pH 6.0-10.0. The major fatty acids were C19 : 0 cyclo ω8c (41.3 %). The major isoprenoid quinone was ubiquinone 10 (Q-10). The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol and an unidentified aminolipid. The DNA G+C content of strain ZC80T was 60.8 mol%. On the basis of phylogenetic analyses and chemotaxonomic and physiological data, strain ZC80T is considered to represent a novel species of a new genus in the family Rhodospirillaceae, for which the name Marivibrio halodurans gen. nov., sp. nov. is proposed. The type strain of Marivibrio halodurans is ZC80T (=CGMCC 1.15697T=NBRC 112461T).


Assuntos
Mineração , Filogenia , Rhodospirillaceae/classificação , Cloreto de Sódio , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Rhodospirillaceae/genética , Rhodospirillaceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/química
10.
Curr Microbiol ; 74(11): 1358-1364, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28819743

RESUMO

A non-motile, spherical or oval extremely halophilic archaeon, strain Y69T, was isolated from a brine of the Yunnan salt mine, China. Colonies on JCM 168 agar plate were round (1-2 mm in diameter), moist, and orange-pigmented. Phylogenetic analysis of the almost-complete 16S rRNA gene sequence showed that the isolate belonged to the species of the genus Halorubrum, with a close relationship to Halorubrum aidingense 31-hongT (98.5%), Halorubrum lacusprofundi ATCC 49239T (98.2%), and Halorubrum kocurii BG-1T (98.0%). The major polar lipids of strain Y69T were phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and a sulfated diglycosyl diether. Strain Y69T grew in 15-30% (w/v) NaCl. The temperature and pH ranges for growth were 25-50 °C and 6.5-9.0, respectively. Optimal growth occurred at 20% (w/v) NaCl, 42 °C, and pH 8.0. Mg2+ was required for growth. The DNA G+C content was determined to be 65.1 mol% by the thermal denaturation method. DNA-DNA hybridization values between strain Y69T and the closely related species were lower than 70%. Based on the data presented in this study, strain Y69T represents a novel species for which the name Halorubrum salsamenti sp. nov. is proposed. The type of the strain is Y69T (=CGMCC 1.15455T = JCM 31270T).


Assuntos
Halorubrum/classificação , Sais , Composição de Bases , DNA Arqueal , Halorubrum/química , Halorubrum/genética , Halorubrum/isolamento & purificação , Fenótipo , Filogenia , RNA Ribossômico 16S/genética
11.
Int J Syst Evol Microbiol ; 67(4): 818-823, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28475027

RESUMO

Two extremely halophilic archaea, strains D90T and D93, were isolated from underground salt deposits of Yunnan salt mine, China. Both strains were pleomorphic or short rods, non-motile, Gram-negative and required 1.7 M NaCl for growth, with optimum at 3.4 M. Mg2+ was not required for growth. Multiple copies of the 16S rRNA gene were obtained for both strains. Sequence similarity analysis of 16S rRNA genes revealed that strains D90T and D93 were closely related to Halobaculum magnesiiphilum MGY-184T and Halobaculum gomorrense DSM 9297T with the sequence similarity between 96.2-98.1 %. The sequence similarity of the rpoB' gene between strain D90T and Halobaculum gomorrenseJCM 9908T was 94.1 %. The DNA G+C contents of strains D90T and D93 were 65.9 and 67.6 mol%, respectively. The major polar lipids of both strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and glycolipid. The DNA-DNA relatedness value between strains D90T and D93 was 90.1±0.5 %, while that between strain D90T and Halobaculum gomorrenseJCM 9908T was 30.0±0.7 %. The comparison of physiological and biochemical characteristics, including the requirements of NaCl, Mg2+, pH, etc., differentiated strains D90T and D93 from Halobaculum magnesiiphilum MGY-184T and Halobaculum gomorrenseJCM 9908T. Therefore, strains D90T and D93 represent a novel species of the genus Halobaculum, for which the name Halobaculum roseum sp. nov. is proposed. The type strain is D90T (=CGMCC 1.15501T=JCM 31273T).


Assuntos
Halobacteriaceae/classificação , Filogenia , Composição de Bases , China , DNA Arqueal/genética , Glicolipídeos/química , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Mineração , Hibridização de Ácido Nucleico , Fosfatidilgliceróis/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio
12.
Int J Syst Evol Microbiol ; 67(5): 1564-1570, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28032536

RESUMO

A novel, extremely halophilic archaeon, strain Y73T, was isolated from a salt mine in Yunnan, China. Colonies formed on solid medium were circular (2-3 mm in diameter), smooth, orange, glistening and convex (~1 mm in elevation). Cells were Gram-stain-negative, non-motile and pleomorphic. Mg2+ was required for growth (optimum at 0.05 M). Optimal growth was observed at 20 % (w/v) NaCl, 42-45 °C and pH 7.5-8.5 under aerobic conditions. 16S rRNA gene sequence comparison showed that strain Y73T was closely related to Halorubrum halophilum B8T (similarity: 98.1 %), Halorubrum lipolyticum 9-3T (97.9 %) and Halorubrum saccharovorum JCM 8865T (97.6 %). Levels of rpoB' gene sequence similarity between strain Y73T and H. halophilum B8T, H. lipolyticum 9-3T and H. saccharovorum JCM 8865T were 93.6, 93.8 and 94.7 %, respectively. DNA-DNA relatedness between strain Y73T and H. halophilum B8T was 38.7±0.5 %, while that between strain Y73T and H. saccharovorum JCM 8865T was 31.0±0.9 % . The DNA G+C content of strain Y73T was 61.9 mol%. The major polar lipids of strain Y73T were phosphatidic acid, phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate as phospholipids, and sulfated diglycosyl diether-1 as glycolipid. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain Y73T represents a novel species, for which the name Halorubrum trueperi sp. nov is proposed. The type strain is Y73T (=CGMCC 1.15503T=JCM 31271T).


Assuntos
Halorubrum/classificação , Mineração , Filogenia , Composição de Bases , China , DNA Arqueal/genética , Glicolipídeos/química , Halorubrum/genética , Halorubrum/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio
13.
Ying Yong Sheng Tai Xue Bao ; 19(1): 157-62, 2008 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-18419089

RESUMO

The study on the dynamics of experimental population of freshwater rotifer Brachionus calyciflorus under exposure of different concentrations of methamidophos (0.01, 0.1, 1.0, 10.0, 100.0, 1000.0 and 10000.0 microg x L(-1)) and 17beta-estradiol (0.001, 0.01, 0.1, 1.0, 10.0, 100.0 and 1000.0 microg x L(-1)) showed that both methamidophos and 17beta-estradiol had significant effects on the mean growth rate of the population, but less affected the mean fertilization rate of mictic females. Methamidophos affected the mean ratio of ovigerous to non-ovigerous females and the mean mictic rate significantly but had less effect on the total resting egg production, while 17beta-estradiol was in adverse. Compared with the controls, both 10.0-10000.0 microg x L(-1) of methamidophos and 100.0 microg x L(-1) of 17beta-estradiol increased the mean population growth rate significantly. 0.1-10000.0 and 10.0 microg x L(-1) of methamidophos decreased significantly the average ratio of ovigerous to non-ovigerous females and the average mictic rate, respectively, and 1000.0 microg x L(-1) of 17beta-estradiol decreased the total resting egg production significantly. Within the range of test concentrations of methamidophos, the relationship between the mean population growth rate (Y, d(-1) and the concentration (X, microg x L(-1) of methamidophos could be described as Y = -2 x 10(-8) X2 + 0.002X + 0.374. The population growth rate could be used to assess the effects of methamidophos on the population dynamics of the rotifer.


Assuntos
Estradiol/toxicidade , Compostos Organotiofosforados/toxicidade , Rotíferos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Água Doce/parasitologia , Dinâmica Populacional , Rotíferos/crescimento & desenvolvimento , Rotíferos/fisiologia , Testes de Toxicidade
14.
Ying Yong Sheng Tai Xue Bao ; 16(3): 455-8, 2005 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15943356

RESUMO

Pinus massoniana and Pinus taiwanensis are the most common and important tree species in the Huangshan Mountain district, and ectomycorrhizae plays an important role in their forestation. Our investigations in 1998-2003 showed that under the pine forests of this district, there were 43 species of ectomycorrhizal fungi belonging to 10 families and 17 genera, of which, 43 were under Pinus massoniana forest, and 12 under Pinus taiwanensis forest. Only a few species were found under young Pinus massoniana forest, with the dominant of Pisolithus tinctorius (Pers.) Coken and Rhizopogon spp., but under mature Pinus massoniana forest, there were plentiful species, with the dominant of Russulaceae, Amanitaceae, Boletaceae and Canthurellaceae. The relationships between woody species and ectomycorrhizal fungi, and between fungi distribution and temperature, moisture and soil condition were discussed in this paper, which would benefit to the further studies on the effects of different ectomyrrhizal fungi to Pinus massoniana and Pinus taiwanensis forests.


Assuntos
Ecossistema , Micorrizas/fisiologia , Pinus/crescimento & desenvolvimento , Simbiose , China , Raízes de Plantas/microbiologia
15.
Ying Yong Sheng Tai Xue Bao ; 15(11): 2195-8, 2004 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-15707341

RESUMO

An untried, low cost, locally available biosorbent for its anionic dye removal capacity from aqueous solution was investigated. Powder prepared from peanut hull had been used for biosorption of three anionic dyes, amaranth (Am), sunset yellow (SY) and fast green FCF (FG). The effects of various experimental parameters (e.g. initial pH and dye concentration, sorbent dosage, particle size, ion strength, contact time etc.) were examined and optimal experimental conditions were decided. At initial pH 2.0, three dyes studied could be removed effectively. When the dye concentration was 50 mg x L(-1), the percentages of dyes sorbed was 95.5% in Am, 91.3% in SY and 94.98% in FG, respectively. The ratios of dyes sorbed had neared maximum values in all three dyes when sorbent dose of 5.0 g x L(-1) and the sorbent particle size in 80-100 mesh was used. The increasing the ion strength of solution caused the decrease in biosorption percentages of dyes. The equilibrium values arrived at about 36 hour for all three dyes. The isothermal data of biosorption followed the Langmuir and Freundlich models. The biosorption processes conformed the pseudo-first-order rate kinetics. The results indicated that powdered peanut hull was an attractive candidate for removing anionic dyes from dye wastewater.


Assuntos
Arachis , Corantes/química , Poluição Química da Água/prevenção & controle , Purificação da Água/métodos , Adsorção , Ânions , Pós , Poluentes Químicos da Água/análise
16.
Ying Yong Sheng Tai Xue Bao ; 14(10): 1739-42, 2003 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-14986378

RESUMO

The north side of Qingliang Mountain Natural Reserveis is very rich of macrofungi resources. There are 160 species, belonging to 72 genera, 38 families, 10 orders and 2 classes, and distributing in the evergreen broadleaf forest, Pinus massoniana forest, evergreen-decidous mixed broadleaf forest, and Pinus taiwanensis forest. According to their economic value, these macrofungi may be grouped into two types: edible (72 species) and medicinal (55 species); and according their ecological habitat, they may be grouped into lignicolous (68 species), entomophilous (84 species), and ectomycorrhizal (21 species). Our study showed a certain regularity of their distribution, i.e., it varied with the ecological conditions of forests, tree species, soil types and altitude. Many economical macrofungi in this region could serve as one of the important natural resources, and had great potential usage on the edibility, medicinal and forestation.


Assuntos
Conservação dos Recursos Naturais , Ecologia , Fungos/isolamento & purificação , Árvores/microbiologia
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