Oligochitosan and sodium alginate enhance stilbene production and induce defense responses in Vitis vinifera cell suspension cultures

Vitis vinifera L. cv. Cabernet Sauvignon cell suspension cultures were treated with oligochitosan (OCS) and sodium alginate (NaAlg) at various concentrations for different exposure times to investigate the effects on stilbene biosynthesis. In this study, adding optimal concentrations of OCS (100 mg l(-1)) and NaAlg (100 mg l(-1)) significantly enhanced both stilbene production inside the cells and trans-resveratrol accumulation in the culture medium without loss of biomass. OCS and NaAlg markedly increased total intracellular stilbene production (1212.05 +/- 36.83 and 990.74 +/- 24.24 mu g g(-1) DW; 96.32 and 60.48 % higher than in untreated cells, respectively), and trans-resveratrol release into the culture medium was induced to the maximum of 3.26 +/- 0.14 and 2.76 +/- 0.12 mg l(-1), respectively. Total phenolics and total flavonoids contents were also highly increased after the application of the two elicitors. The expression levels of genes involved in stilbene and flavonoid biosynthesis were significantly up-regulated in the presence of OCS and NaAlg. Further, the expression levels and enzyme activities of two pathogenesis-related proteins, chitinase and beta-1,3glucanase, were induced after the addition of elicitors. The results suggest that OCS and NaAlg can significantly enhance the production of stilbene in V. vinifera cell cultures and may induce the defense responses by the upregulation of chitinase and beta-1,3-glucanase at transcript and enzyme activity levels.