scholarly journals Zoosporic fungi growing on the eggs of Coregonus lavaretus maraena (Bloch, 1779) from Lake Miedwie in Pomerania

2001 ◽  
Vol 31 (1) ◽  
pp. 141-149
Author(s):  
Bazyli Czeczuga ◽  
Marek Pietrucha ◽  
Elżbieta Muszyńska
2010 ◽  
Vol 35 ◽  
pp. 171-176 ◽  
Author(s):  
José de Ribamar De Sousa Rocha ◽  
Edílson Páscoa Rodrigues ◽  
Hamanda Soares Viana Pereira da Silva ◽  
Lidiane Martins Alves de Sousa ◽  
Brenda Skally Viera Barros

Geographical distribution of the Aphanodictyon papillatum Huneycutt ex Dick (Saprolegniales) in the Brazil. Palavras-chave. Aphanodictyon papillatum, Brasil, fungo zoospórico. Key words. Aphanodictyon papillatum, Brazil, zoosporic fungi.


1999 ◽  
Vol 40 (11-12) ◽  
pp. 109-114 ◽  
Author(s):  
Aarno Karels ◽  
Markus Soimasuo ◽  
Aimo Oikari

Reproductive indices like gonad size, fecundity, egg size and sex steroid levels of estradiol-17β and testosterone, vitellogenin in the blood as well as bile conjugates and liver 7-ethoxyresorufin O-deethylase (EROD) activity were studied in populations of perch (Perca fluviatilis L.) and roach (Rutilus rutilus L.) and experimentally exposed juvenile whitefish (Coregonus lavaretus L. s.l.) at the Southern Lake Saimaa (S.E. Finland). Our studies showed that the introduction of elemental chlorine free (ECF) bleaching and secondary treatment of effluents in a modern activated sludge plant at the mill in 1992 have substantially reduced the exposure of feral and caged fish to organochlorines. The liver EROD activity was noticeably lower in feral and caged fish near the mill indicating lesser impacts on the liver mixed function oxygenase (MFO) system. However, at the mill site, liver EROD activies in feral and caged fish still tend to be one to four times higher than at the reference sites. Significantly decreased plasma estradiol-17β and testosterone concentrations in perch and roach in the period of development of the gonads (autumn and winter) indicate that there were endocrine disrupting compounds present in the lake receiving ECF pulp and paper mill effluents. Cause-effect relationships, however, are difficult to establish.


1998 ◽  
Vol 64 (4) ◽  
pp. 1490-1496 ◽  
Author(s):  
P. R. Jensen ◽  
K. M. Jenkins ◽  
D. Porter ◽  
W. Fenical

ABSTRACT Significantly fewer thraustochytrid protists (zoosporic fungi) were observed in association with healthy leaf tissue of the marine angiosperm Thalassia testudinum than in association with sterilized samples that were returned to the collection site for 48 h. In support of the hypothesis that sea grass secondary metabolites were responsible for these differences, extracts of healthyT. testudinum leaf tissues inhibited the growth of the co-occurring thraustochytrid Schizochytrium aggregatum and deterred the attachment of S. aggregatum motile zoospores to an extract-impregnated substrate. By using S. aggregatumfor bioassay-guided chemical fractionation, a new flavone glycoside was isolated and structurally characterized as luteolin 7-O-β-d-glucopyranosyl-2"-sulfate. Whole-leaf tissue concentrations of this metabolite (4 mg/ml of wet leaf tissue) inhibited S. aggregatum attachment, and a significantly lower concentration (270 μg/ml) reduced thraustochytrid growth by 50%, suggesting that natural concentrations are at least 15 times greater than that needed for significant microbiological effects. These results offer the first complete chemical characterization of a sea grass sulfated flavone glycoside and provide evidence that a secondary metabolite chemically defends T. testudinum against fouling microorganisms.


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