Hi everyone ... Why contamination with anaerobic bacteria, yeasts and molds increase (not decrease) the pH of the culture medium?

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Phil Geis

They may have no effect, increase or decrease pH. Metabolism of carbohydrates commonly used in media typically lowers pH with production of organic acids,

Article Carbon Source Influence on Extracellular pH Changes along Ba...

Robert Adolf Brinzer

Depends on the composition of the media and the type of contamination. The increasing pH is probably due to amino acid catabolism (often glutamine/glutamate) releasing ammonia.

Wessam Sharaf Eldin

Many thanks Phil Geis Robert Adolf Brinzer