Please, how do I get rid of Oscillatoria sp(contaminant) from Monoraphidium culture? tried isolate but not yielding.
Allow the culture to grow in wastewater supplemented with nitrate. This would select Monoraphidium sp., a microalga with excellent nitrogen reduction potentials while suppressing the growth of Oscillatoria species which prefers to fix its nitrogen. Alternatively, you could reduce light intensity which will favour Monoraphidium sp. but de-select Oscillatoria sp. which requires high light intensities to proliferate.
Thank you for the response. Today, realising that Oscillatoria sp are filamentous hence they tend to settle at the bottom, I first sieved with a new plankton net. Then I allowed it settle for a while, used dropper to take from upper part for viewing. Convinced it was pure Monoraphidium, then I poured out the upper part into a sterilized flask. Viewed both 2 parts with microscope. Did same process twice. Did same for Scenedesmus sp culture.
Allow the solution to settle, Oscillatoria sp will move down and carefully scoop off.
@Maurice Ekpenyong Sir, when you said wastewater supplemented with nitrogen, am I to add nitrogen to wastewater or wastewater that already have nitrogen existing? Have access to fish pond wastewater at my University.