An experiment on oat plants by scientist Maria Quiles, revealed that extreme light intensity can inhibit photosynthesis and result in the lack of PS II activity. This reduction leads to an increase in NAD(P)H and PTOX levels which then causes the stimulation of chlororespiration.
Oat leaves were incubated and Chlorophyll fluorescence emission was used to examine the effect of extreme light intensity. As the emission of the Chlorophyll fluorescence increased the PQ pool decreased. This stimulated the cyclic electron flow, causing NAD(P)H and PTOX levels to ultimately incline and initiate the process of chlororespiration within the thylakoid membrane of oat plants.
The effect of adding n-propyl gallate to the incubated leaves was also observed. N-propyl gallate is a molecule that helps distinguish between PQ reduction and oxidation activities by inhibiting PTOX. Quiles noted an increase in chlorophyll fluorescence inside the thylakoid membrane of plant cells, after the addition of n-propyl gallate. The result led to the stimulation of the NAD(P)H enzyme and its cyclic pathway; causing a continuous increase in chlorophyll fluorescence levels within the oat.