Winogradsky column lab page!


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Welcome to the Winogradsky column lab page! Students from the Departments of Biological Applications and Technology, University of Ioannina and Icthyology and Aquatic Environment, University of Thessaly, Greece and the Microbiology course, Faculty of Sciences, University of Cádiz, Spain, discuss their findings on Winogradsky columns they constructed!

If you want to add a post, please feel free to contact the blog administrators (Hera Karayanni, Sokratis Papaspyrou or Kostas Kormas)!



Καλωσορίσατε στη σελίδα των Winobloggers! Διαδικτυακός τόπος συνάντησης φοιτητών, φοιτητριών και διδασκόντων δύο Τμημάτων από την Ελλάδα: Tμήμα Βιολογικών Εφαρμογών και Τεχνολογιών, Παν/μιο Ιωαννίνων και Τμήμα Γεωπονίας, Ιχθυολογίας και Υδάτινου Περιβάλλοντος, Παν/μιο Θεσσαλίας και ενός από την Ισπανία: Σχολή Θετικών Επιστημών, Πανεπιστήμιο του Cadiz. Παρακολουθούμε, σχολιάζουμε, ρωτάμε, απαντάμε σχετικά με τα πειράματά μας, τις στήλες Winogradsky!


Bienvenidos a la pagina web de los Winobloggers! Aquí los estudiantes y profesores de dos departamentos griegos, el Departamento de Aplicaciones y Tecnologías Biológicas de la Universidad de Ioannina y el Departmento de Agricultura, Ictiología y Sistemas Acuáticos de la Universidad de Thessalia, junto con los estudiantes de Microbiología de la Facultad de Ciencias en la Universidad de Cádiz, se reúnen para observar, comentar, preguntar y responder a preguntas relacionadas con nuestro experimento, la columna Winogradsky.


Winogradksy columns

Winogradksy columns
'In the field of observation, chance only favors the prepared mind' Pasteur 1854

Blog posts

Monday, 9 May 2016

UCA_8&4B_3- 8th Week: The column... my treasure

After eight weeks, some changes are noticeable.

Dark Column: Probably column changes are not too remarkable this time, they could be group as a colour darkening. It could be due to an increase bacteria concentration. Top layer is unchanged.

Here, we include an explanation of why dark colour is produced:

Dark area growth indicates the presence of two types of bacteria. Desulfovibrio and Clostridium.
Desulfovibrio genus bacteria uses both by-products of the fermentation carried out by genus Clostridium anaerobic respiration and sulphate salts added in the sediment, generating large amounts of H2S in the process. This H2S reacts with iron present in the sediment, producing ferrous sulphide which justifies the black colour.
As said before, dull area progressively expands. This is caused due to Clostridium strictly anaerobic condition (it will die in presence of oxygen). As oxygen which is still contained in the sediment disappears, population will be more spread, producing more metabolites (ethanol and organic acids). This contributes with the increase of Desulfovibrio population thus producing more SH2 and iron sulphide, obscuring that area of the column.
Clostridium bacteria metabolize the cellulose which comes from paper in order to produce glucose. Afterwards, by fermentation, energy will be gained, obtaining these metabolites in the process. 



Light column: Water has become orange, mollusk died and bateria dominate the column. In the light zone many bacteria have grown while in the dark zone there is nothing. We can see all around the bottle a very intense orange due to iron oxide. In the bottom we see again the sulfate-bacteria that produce the dark colour and we can also see violet spots that tell us there are sulfure-bacteria.



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