Inhibitors of PMEs regulate plant PME activity.
More recently, over-expression of a Petunia inflata PME in potatoes caused a transient increase in stem elongation in regions with reduced PME activity [ 19].
These treatments also reduced the PME activity above the 96% of its initial activity.
In a separate experiment we found a positive correlation between the PME activity and the residual content of the catechins suggesting that polyphenoloxidase (PPO, EC 1.14.18.1) and oxidized polyphenols play a role in the PME activity level after HP treatment.
PME activity was measured by the methanol release during the storage of samples at 4 °C for 1 month.
Enzyme pectin methylesterase (PME) activity, which is the major cause of cloud loss of juices, was also measured.
The PME activity of hyperhydric leaves was higher (4 10 times) compared to controls of the three varieties.
The effect of different ultra high pressure homogenization (UHPH) treatments on pectin methylesterase (PME) activity and on the contaminating microorganisms of orange juice was investigated.
In conclusion, increasing in storage duration significantly affected the fruits quality by increasing in ethylene, PME activity, PG activity, decay and decreasing the phenol content and firmness.
Fruits treated by UV-C and CaCl2 had higher phenol and firmness, and less PME activity, PG activity, ethylene production, and decay than the control fruits.
Moreover, PME activity in pollen from a vangard1 mutation is only 82% of that in the WT, and grains of the former have reduced tube growth (Jiang et al. 2005).
