The experiment of Winogradsky column is to observe microbiology interaction of microbes using pond mud. The aim of this paper is to describe structural and chemical features in Winogradsky column and to show the acknowledgement of microbial cells in Winogradsky column.
Materials of experiment
1. Prepare pond mud
2. Add calcium sulfate and calcium carbonate
3. Add piece of paper
4. Add pond water
5. Seal top of the column
6. Put beside window
Process (sequence of the reaction)
The less of oxygen makes oxygen enrichment at the top as well as anaerobic condition at the bottom (O2 gradient). Clostridium and other anaerobic bacteria dominate under anaerobic conditions at the bottom. Cellulose from the paper into glucose and that would be a trigger for the bacteria (Clostridium) to take in the glucose and partially break it down by fermentation to gain energy and to produce ethanol and organic acids as by-products. The by-products from Clostridium feed into other bacteria nearby in the deep mud of the column. Desulfovibrio bacteria use these organic molecules as carbon sources. Desulfovibrio uses sulfate, rather than O2, as a final electron receptor in respiration, producing H2S. The activity of Desulfovibrio creates a gradient of H2S, with high H2S at the bottom, low at the top. H2S feeds into the metabolism of two types of photosynthetic bacteria: the green sulfur bacteria (e.g. Chlorobium) and the purple sulfur bacteria (e.g. Chromatium). These bacteria begin to proliferate as they use CO2 from calcium carbonate as a carbon source, H2S from Desulfovibrio as an electron donor, and light as the energy source needed produce organic molecules. (Perry, et al., 2002) The green sulfur bacteria can tolerate higher concentrations of H2S than the purple sulfur bacteria can tolerate....