I have grown Yeast in synthetic medium. In two days all the substrate were consumed, However, the growth was observed until day 5 and becomes stationary after day 5. What could be the possible explanation?
Also, What will be the mathematical relation of substrate removal and delay in growth?
Yes, substrate was completely consumed on day 2 but growth continued due to excess nutrients consumed by yeast from substrate present in the system of yeast. And growth of yeast may stop after day 5 because excess nutrients obtained from substrate may have been completely utilized for growth by the yeast. Growth of yeast may have become stationary after day 5 due to yeast attaining its highest level of maturity . Also the absence of nutrients from the substrate may have prevented proliferation/ reproduction or cell division
The mathematical relation could be growth or proliferation of yeast is depended on nutrients present in substrate or total substrate available.
Growth or proliferation of yeast is directly proportion to nutrients of substrate available
Hello Valentine Mbatchou ,
Thank you for your response. How can I justify this in Mathematical equation? I have made a kinetic model with monod equation and my model does not show any growth after 2 days as there is no substrate available? However, in my experimental work, growth was observed until day 5? Is there any equation which can describe the relation of excess nutrient consumption and growth time? Thank you
Generally, the growth of microbes does not come to a stop instantaneously, it happens overtime. Before the depletion of nutrients, there is active uptake of substrate by cells. So while there appears to be no more substrate in the medium, cells have already gathered enough to keep up with their physiological activities including reproduction (this however proceeds slowly at this stage due to constraint in resources). For this reason you are likely to observe a relatively slight increase in biomass over a certain period of time. But as the nutrient deprivation continues, biomass begins to decrease as some point.
Have a look at this literature, it should be helpful.
https://doi.org/10.1016/B978-0-08-099953-1.00002-8
- Badges
- Science topic
- Similar topics
- Mathematics