Winogradsky column lab page!

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, 16 March 2015

Cadiz, 9B: Winogradsky column, first week.

Hi, everyone!  We are three students from UCA
The sources of the mud that we used are the river and the beach,  salt water was added to the mixture. We've mixed the mud with paper, calcium carbonate , ferrous sulfate and calcium sulfate.
The paper was added to the mixture due to the fact that it provides a source of carbon(cellulose), the calcium carbonate was used because it produces carbon dioxide, another source of carbon. Ferrous sulfate and calcium sulfate were used as a source of sulphur.
The Winogradsky column was made on Tuesday 3rd march 2015.
The mud was mixed with the carbon and sulphur sources in a bucket, then, it was added to the bottle and packed in the bottom. More mud was added to fill two thirds of the bottle capacity. Then the salt water was  added to the bottle.
The column has been placed next to a window.
The added material triggered microbial activity that depletes the oxygen in the mud, creating an oxygen gradient in the column. Under these anaerobic conditions, anaerobic bacteria like Clostridium predominate. These bacteria use the cellulose from the paper to obtain glucose subunits. After obtaining glucose, the bacteria partially break it down by fermentation, producing by-products like ethanol and organic acids.
These by-products feed into other bacteria. Desulfovibrio use the organic acids as a carbon source, they also use the sulfate that was added to the column(desulfovibrio bacteria use sulfate as a final electron receptor in respiration, producing hydrogen sulfide.).
The hydrogen sulfide is used by the green sulphur bacteria and the purple sulphur bacteria, which will also use carbonic dioxide obtained from calcium carbonate.
The presence of iron bacteria may explain the orange coloured water. The black dots are probably desulfovibrio bacteria,  the foul odour of the column is caused by them. Finally, the brown colour can be explained by the presence of anaerobic bacteria.

No comments:

Post a Comment