Cell suspension cultures were initiated from friable calluses obtained from leaf segments cultured
with the abaxial surfacein contact with agar-solidified MSM medium supplemented with
28.9 M PIC for 90 days. Three grams of callus were transferred to125 ml erlenmeyers flasks
containing 30 ml of liquid medium (MSMsupplemented with 28.9 M PIC) per flask. Flasks were
closed withtwo layers of aluminum foil and incubated on a gyratory shaker(100 rpm) at 25±2 ◦C, in
the presence or absence of light for 30days. Light source and level were the same as described in
item 2.1.To determine growth kinetics, the cells were harvested by filteringthrough filter paper
(Whatman 1 mm) using a filter unit(Nalgene TM Cat. No. 320-2533) connected to a vacuum pump.
The cell biomass accumulation was estimated by measurementof fresh (FW) and dry (DW) weights.
Dry mass was determinedafter drying the cells at 60 ◦C to constant weight. Samples were
collected at 2–3 days intervals during a 30-day period, and eachpoint of the growth curve
represents the mean of three independentdeterminations (flasks). Subcultures were carried out
duringthe exponential growth phase.2.5. Statistical