effect of chitosan and chitin oligomers on gene expression and lignans production in Linum album cell cultures

ABSTRACT

Linum album, a herbaceous and medicinal plant, has been shown to accumulate anti-tumor podophyllotoxin [PTOX] and related lignans. In this study, we have verified the time-course of cell growth, lignan production in cells treated with chitosan and chitin oligomers. To study mechanism of chitosan and chitin oligomers action, expression of phenylalanine ammonio-lyase [PAL], cinnamoyl-CoA reductase [CCR], cinnamyl alcohol dehydrogenase [CAD] and pinoresinol lariciresinol reductase [PLR] genes were investigated. The cells were treated with 100 mg l[-1] chitin and chitosan oligomers. Cells were harvested for 5 days after elicitation. lignans quantified by reverse-phase high-performance liquid chromatography [HPLC]. Cell samples frozen with liquid N2 were used to elucidate the expression level of genes by quantitative PCR [qPCR]. Cells elicited with chitosan hexamer for 5 days yielded the highest amount of PTOX [73.5 micro g/g dry weight] and lariciresinol [96 micro g/g DW] which were about 3-fold and 2-fold higher than control, respectively. The expression of genes by oligomers was increased, reaching a peak at 3 day after treatment. Chitosan and chitin oligomers up-regulate the production of PTOX, by effecting on gene expression of PTOX biosynthesis pathway