Development of Sinningia magnifica (Otto & A. Dietr.) Wiehler (Gesneriaceae) tissue culture for in vitro production of quinones and bioactive molecules

Quinones and phenolic glycosides display several biological activities and has been reported in Sinningia species (Gesneriaceae family). The plant tissue culture technique is an excellent tool for metabolism process studies and metabolites extraction. The aim of this work was the callogenesis induction and the secondary callus culture optimization in Sinningia magnifica (Otto & A. Dietr.) Wiehler, varying different types and concentrations of growth regulators, light, antioxidant, and culture medium. These conditions may influence the potential and the morphology of the induced callus, and thus the production and variation of secondary metabolites. Our studies found that for S. magnifica, the best method was fixed using Murashige and Skoog medium culture, in the absence of light, at a concentration of 8.0 mgL⁻¹ of 6-Benzylaminopurine and of 2,4-dichlorophenoxyacetic acid, with a callus development reaching a plateau in about 45 days. The potent antioxidant activity of calli was compared with the in natura plant and demonstrated the greater variety of secondary metabolites. 7-hydroxy-6-methoxy-tectoquinone and 7-hydroxy-6-methoxy-α-dunnione were found in higher quantities in in vitro plants culture compared with the in natura plant, demonstrating the importance of using other methods in order to improve the secondary metabolites production and the advantages of this source for bioactive compounds development and exploitation.