In vitro propagation strategies of Puya chilensis as an alternative for obtaining new cysteine proteases

Abstract

P. chilensis is an endemic species of Chile belonging to the Bromeliaceae family, known for its morphological plasticity and ecological importance. In recent years, greater attention has been paid to its conservation due to the indiscriminate use of its populations for food and medicinal purposes. In vitro culture is a tool for the propagation and conservation of endemic species, as well as for obtaining bioactive plant molecules. In Chile, P. chilensis is the most representative within the Puya genus. This study was focused to establish an in vitro propagation protocol of P. chilensis using culture systems that allow the production of proteolytic enzymes. The combined effect of plants cuts and the application of 0.5 µmol. L-1 of BAP and GA3 favored the in vitro multiplication of P. chilensis. Culture in liquid medium induced greater morphological development and early differentiation of anatomical structures in the leaves of P. chilensis in vitro. The TIS provided photoautotrophic conditions during in vitro cultivation and guaranteed 100% plant survival upon transfer to the greenhouse. The management of cultivation conditions and the efficient use of TIS allowed the generation of P. chilensis plants with an optimal degree of development for obtaining proteolytic extracts. The main enzymes present in the extracts of P. chilensis plants grown in vitro belong to the cysteine type. This study proposes for the first time an optimized protocol for the propagation and conservation of P. chilensis, enhancing its uses as a source of biologically active molecules for the biotechnology and pharmaceutical industries.