Anthraquinone production in hairy roots of Rubia tinctorum

PERASSOLO, M; GIULIETTI, AM; RODRÍGUEZ TALOU, J

Congreso; XLVIII Reunión Anual de la SAIB; 2012

Anthraquinones (AQs) are anthracene derivatives that are synthesized by several plant families, including Rubiaceae. These secondary metabolites exhibit interesting in vitro properties, such as antioxidant, anticancer, antimicrobial activities. Production of these compounds by in vitro culture is an attractive alternative to extraction from their natural source. In this work, we established a hairy root culture of Rubia tinctorum and we evaluated their performance and AQ production in 250 ml erlenmeyer flasks in two different culture media: Gamborg B5 (half-saline strength; B51/2) and Lloyd and McCown's Woody Plant Media (WPM). The final biomass achieved was 150 g/L (fresh weight; FW) after 42 days of culture in WPM (μ= 0.11 d-1), whereas biomass accumulation in B51/2 was significantly slower (100 g/L; μ= 0.10 d-1). Intracellular AQ accumulation was enhanced in B51/2 (11.88 μmol/g FW after 35 days) when compared to WPM (6.44 μmol/g FW). Similar results were observed for AQ liberation to the culture medium (84.6 and 7.5 μmol/L, respectively, after 35 days). The differences found in AQ and biomass yields can be attributed to differences in the composition of the culture media (S, P and N), not only as limiting substrates but also because they might be involved in the regulation of AQ synthesis. These results are promising for further improving AQ yields and for scaling up the process