Proteolytic and clotting activities of cell suspension cultures of Ficus carica under stress saline conditions

Miguel, Maria Graça; Lima Costa, Maria Emília

http://hdl.handle.net/10400.1/6274

Use this identifier to reference this record.

Name:	Description:	Size:	Format:
miguel1998.pdf		260.92 KB	Adobe PDF	Download

Send Feedback

Authors

Miguel, Maria Graça

Lima Costa, Maria Emília

Abstract(s)

The latex of fig trees can be used for cheese making due to the presence of ficin, a proteolytic enzyme. The objective of this work was to establish cell suspension cultures of F. carica to obtain the plant proteases and study the milk clotting proteases from these cultures under saline stress conditions. Cell suspension cultures of F. carica were established from calli maintained in GD (Gresshoff and Doy, 1972) basal medium, supplemented with 30 g/l sucrose, 0.01 mg/l NAA and 1 mg/l BA. Cell suspension cultures maintained in GD basal medium, supplemented with 30 g/l sucrose, 0.01 mg/l NAA and 1 mg/l BA or in Gamborg's B5 medium (Gamborg et al., 1968) supplemented with 20 g/l sucrose, 0.5 mg/l and 0.2 mg/l Kin were characterized by determining several parameters; fresh weight, dry weight, intracellular protein and consumption of nitrate, ammonium, and other nutrients from the medium. At the same time, the proteolytic and coagulant activities were determined on these cultures as well as on the others submitted at different concentrations of sodium chloride. The cultures maintained in GD medium induced a lower production of biomass either in terms of fresh or dry weight than those maintained in Gamborg's B5 medium as well as a slower mobilization of nutrients from the culture medium. The cultures maintained in Gamborg's B5 medium seem to have higher proteolytic activity than those maintained in GD medium, however, the clotting activity on milk seems to be similar. The proteolytic activity was changed by the presence of sodium chloride.