2.8. Determination of the activities of fruit softening enzymes in
pulp tissue
Activities of exo-PG, endo-PG, PE and EGase were determined
in pulp tissues following the method as described by Khan and
Singh (2007) with some modification. The fruit pulp tissue (13.0 g)
was homogenized with 13.0 mL cold solution, containing 12%
polyethylene-glycol and 0.2% sodium bisulphite (NaHSO3). The
supernatant was immediately stored at −80 ◦C for determination
of protein content. Following centrifugation at 4 ◦C for 40 min at
15,000 × g, the pellet was washed with a 13.0 mL aqueous solution
of NaHSO3 (0.2%) and re-centrifuged at 4 ◦C for 40 min at 15,000 × g.
The pellet was stored at −80 ◦C for determination of exo- and endoPG,
PE and EGase