In vitro propagation of insectivorous plants for phytochemical purposes

Dissertação mest., Engenharia Biológica, Universidade do Algarve, 2009

The aims of this research work were to establish in vitro propagation protocols for the insectivorous plants D. intermedia, D. rotundifolia and P. vulgaris, using seeds as explants, in order to produce plants for biocompound extraction and to replenish natural populations. The antioxidant capacity of the extracts prepared from in vitro cultures of these species was evaluated. The establishment of a simple protocol for in vitro propagation of D. intermedia is reported. Protocols for micropropagation of P. vulgaris and D. rotundifolia were initiated but still need to be improved. Cultures of all three species were initiated from shoots of in vitro produced seedlings. The effect of three MS medium concentrations, ¼MS, ½MS and MS, without PGR were tested in D. intermedia and P. vulgaris. The same media supplemented with 0.1 mg l-1 KIN were investigated in D. intermedia and ¼MS supplemented with 0.5 mg l-1 KIN or ZEA were investigated in P. vulgaris. In all media D. intermedia shoots rooted during the proliferation phase, presenting a multiplication and rooting percentage above 90%. The highest mean number of shoots was attained in ¼MS and ¼MS supplemented with 0.1 mg l-1 KIN. All the D. intermedia plants were successfully acclimatized to ex vitro conditions. The formation of roots also occurred during P. vulgaris proliferation phase, though with poorer results for both proliferation and rooting. Nevertheless, the best results were obtained in the media supplemented with cytokinins. In D. rotundifolia the media tested were ¼MS and MS. Multiplication percentage and mean number of shoots was higher in ¼MS medium and no rooting was observed. Antioxidant activity of D. intermedia, D. rotundifolia and P. lusitanica extracts was measured using three different methods: ORAC, F-C phenolics and TEAC. Methanol and standard maceration improved the efficiency of the antioxidant extraction procedure. For all tested methods P. lusitanica presented the highest antioxidant activity, representing a possible good source of antioxidants.