Why is CO2 not produced in lactose Intolerance?

When Lactose reached the large intestine its broken down by microorganisms (fermentation).

The question is:
Q : Suggest a reason why the gas is unlikely to be CO2

Ive researched the internet and cant seem to find anything

Reply 1

Angry cucumber

I believe the microorganisms which use lactose as their respirative substrate break it down into a mixture of H2, CO2 and methane

Reply 2

Eloades11

Original post by jack97

My best guess would be that it has something to do with the biochemistry in lactose metabolism by bacteria colonising in the colon. I remember something about hydrogen being the main gas product of lactose metabolism.

Reply 3

jack97

the question doesnt make sense to me, i always thought that CO2 was mainly produced in fermentation.

it may be because there are a similar amount of Carbons to Oxygens in its structure therefore there isnt enough oxygen to produce CO2. (12 CArbons and 11 Oxygens)

Reply 4

shumen9523

Hey, I'm not sure if this is the answer in the mark scheme/ model answer but read this:
http://www.uic.edu/classes/phar/phar332/Clinical_Cases/carbo%20metab%20cases/lactose%20intol.htm
Apparently, bacteria use co2 and hydrogen to produce methane and this causes the concentration of CO2 to decrease.
Hope this helped

Reply 5

Zara-Ajmal

Carbon dioxide is formed in aerobic respiration, whereas conditions in the colon are anaerobic.