BIOPRODUCTION OF BENZYL ISOTHIOCYANATE IN SALVADORAPERSICA L. CALLUS TISSUE

In vitro production of valuable secondary metabolites is the best suited alternative over traditional field cultivation and chemical synthesis, for mass production of natural pure chemicals more cheaply and rapidly, independently from climate change and negative biotic and abiotic influences on secondary metabolites production in naturally grown plants. Benzyl isothiocyanate (BITC), a major compound in Salvadorapersica L., is one of the naturally occurring isothiocyanates, and has antioxidant and anticancer properties. In this study, an in vitro method was developed for the production of BITC from callus cultures of S. persica, a rare medicinal plant in Egypt. Two types of explants; leaf and stem sections were cultured on Murashige and Skoog (MS) medium, supplemented with different concentrations of 2,4-dichlorophenoxy acetic acid (2,4-D) independently or in combination with kinetin (Kn), for callus induction and mentainance. MS medium supplemented with 1 mg/l 2,4-D gave the maximum mean fresh and dry weights of yellowish white friable callus obtained from stem sections. Friable and beige coloured callus was induced when leaf sections were cultured on MS medium supplemented with 0.5 mg/l of each of 2,4-D and Kn, with the maximum fresh and dry weights of callus. The effect of different concentrations of two amino acid precursors; phenylalanine (Phe) and cysteine (Cys), on the callus growth and BITC content was determined. Gas liquid chromatography (GLC) analysis showed the presence of high BITC content in the callus when compared to the intact plant. Phe at the concentration of 12.5 mg/l increased the amount of BITC in callus cultures (29.88 µg/g dry weight of callus), produced from stem sections, by about 4.5 times that in the stem of the intact plant and 8 times that in the leaves of the intact plant. This protocol is a stepping stone for the in vitro production of one of the chemo protective agents without exploiting natural plant resources