Use of the cell quota and chlorophyll content for normalization of cylindropermopsin produced by two Cylindrospermopsis raciborskii strains grown under different light intensities
Resumen
The production of cylindrospermopsin (CYN) by Cylindrospermopsis raciborskii (Woloszynska) Seenaya and Subba Raju (Cyanobacteria) was already shown to be changed by variations in light intensities. Influences of light intensity on CYN production by two different C. raciborskii strains (CYP011K and CYP030A) were studied in batch culture conditions. The strains were grown under photon light intensities from 40 to 348 μmol photons m-2 s-1. The growth rates were measured by exponential regression of cell number variation along the time. The concentration of chlorophyll-a (Chl-a) was measured by spectrophotometric methods and the CYN concentration was measured by high-performance liquid chromatographic methods. Data from these CYN analyses were evaluated as cell quota (ng CYN 10-6 cells) or as the relative proportion between toxin concentration and chlorophyll-a concentration (CYN Chl-a-1). The CYP011K showed higher growth rates than the CYP030A strains. According to the cell quota results, the production of CYN by these two strains of C. raciborskii is not affected by the intensity of the surrounding light during growth. However, analysis of the relative proportion of CYN Chl-a-1 led to different interpretations, as a negative relation between light intensity and CYN production.Descargas
Descargas
Publicado
Cómo citar
Número
Sección
Licencia
Copyright © 2006 ECOTOX-Brasil
Copyright notice: It is a condition for publication that manuscripts submitted to this journal have not yet been published and will not be simultaneously submitted or published elsewhere. By submitting a manuscript, the authors agree that copyright for their article is transferred to the Sociedade Brasileira de Ecotoxicologia (ECOTOX-Brasil) if and when the article is accepted for publication. The copyright covers the exclusive rights to reproduce and distribute articles, including reprints, photographic reproductions or any other reproduction of a similar nature, including translations. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without permission of the publisher.
Notice: While every effort is made by the EEC, editors and editorial board to see that no inaccurate or misleading data, opinions or statements appear in this journal, they wish to make it clear that the contents of the articles and advertisements published herein are the sole responsibility of the contributors or advertisers concerned. Accordingly, the EEC, the editorial board and editors and their respective employees, officers and agents accept no responsibility or liability whatsoever for the consequences of any inaccurate or misleading data, opinion or statement.
