Journal of Applied Phycology

, Volume 28, Issue 3, pp 1713–1723 | Cite as

Evaluation of methanol preservation for molecular and morphological studies in cyanobacteria using Planktothrix agardhii

  • Catarina ChurroEmail author
  • Elisabete Valério
  • Luís Vieira
  • Paulo Pereira
  • Vitor Vasconcelos


Molecular studies on cyanobacteria often involve filtering and freezing of samples leading to loss of cell morphological features. Methanol is often used in preservation of biological materials in association with other fixatives. This study evaluates the application of methanol in the preservation of DNA for molecular studies as well as for the preservation of cell morphology for morphometric analysis in filamentous cyanobacteria. In the present study, both culture and environmental bloom samples were preserved using a cold methanol dehydration series (50, 70, and 100 %) and stored at −20 °C for up to 2 years. The DNA quantity and quality, nucleotide sequence retrieval, and real-time PCR quantification were analyzed over time. Morphometric cell analysis was performed on preserved samples. Results show that the DNA extracted from samples preserved up to 6 months was successfully quantified by real-time PCR. After that period, the DNA quantity decreased with the preservation time. Nevertheless, we were able to detect/amplify the target fragment in samples preserved up to 2 years. The DNA sequence and cell morphology were also maintained during the preservation time. Thus, methanol preservation is an adequate method to preserve molecular information and morphological features after long storage periods.


Cyanobacteria Lugol’s iodine Methanol Preservation Real-time qPCR rpoC1 



This research was partially supported by the European Regional Development Fund (ERDF) through the COMPETE - Operational Competitiveness Program - and FCT - Foundation for Science and Technology national funds through projects PPCDT/AMB/67075/2006 and PEst-C/MAR/LA0015/2013, the Post-Doc research grant SFRH/BPD/75922/2011 to E. Valério and Ph.D. research grant SFRH/BD65706/2009 to C. Churro. The authors acknowledge S. Paulino from the Laboratory of Biology and Ecotoxicology of the National Institute of Health Doutor Ricardo Jorge for the assistance in the biovolume measurements.


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Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  • Catarina Churro
    • 1
    • 2
    • 3
    Email author
  • Elisabete Valério
    • 2
    • 3
  • Luís Vieira
    • 4
  • Paulo Pereira
    • 3
  • Vitor Vasconcelos
    • 1
    • 2
  1. 1.Departamento de Biologia, Faculdade de CiênciasUniversidade do PortoPortoPortugal
  2. 2.Centro Interdisciplinar de Investigação Marinha e Ambiental, CIIMAR/CIMARUniversidade do PortoPortoPortugal
  3. 3.Departamento de Saúde Ambiental, Laboratório de Biologia e EcotoxicologiaInstituto Nacional de Saúde Dr. Ricardo JorgeLisbonPortugal
  4. 4.Departamento de Genética Humana, Unidade de Tecnologia e InovaçãoInstituto Nacional de Saúde Dr. Ricardo JorgeLisbonPortugal

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