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Linum album is an herbaceous and medicinal plant that has important lignan such as podophyllotoxin (PTOX). PTOX has antiviral and anticancer properties. Since the chemical synthesis of PTOX is an expensive process, production of PTOX using cell and cultures of linum species is a cost-effective alternative approach. Various strategies have been employed to increase the production of secondary metabolites in cell cultures. In this study, we have verified the effect of chitosan on cell growth, PTOX production in 1, 2, 3 and 5 days after treatment. Cells elicited with chitosan for 5 days yielded the highest amount of PTOX. To study mechanism of chitosan action, expression of phenylalanine ammonio-lyase (PAL), cinnamoyl-CoA reductase (CCR), cinnamyl alcohol dehydrogenase (CAD) and pinoresinol lariciresinol reductase (PLR) genes were investigated. The expression of genes were increased, reaching a peak at 3 day after treatment. Chitosan up-regulate the production of PTOX, by effecting on gene expression of PTOX biosynthesis pathway.