Cultura de tecidos desdiferenciados e embriões somáticos de Petiveria alliacea L. visando à produção de substâncias bioativas

• Autor(a) principal: Paiva, Leila Cantelmo
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/7923
• topic: Guinea; Phytolaccacea; Callus; Cell suspension; Somatic embryogenesis; Dibenzyl trisulfide; Guiné; Phytolaccacea; Calo; Células em suspensão; Embriogênese somática; Dibenzil trissulfeto; Petiveria alliacea - Propagação-in-vitro; Petiveria alliacea - Anatomia; CNPQ::CIENCIAS BIOLOGICAS::BOTANICA::BOTANICA APLICADA

Petiveria alliacea L. belongs to the family Phytolaccacceae and is commonly known as "guinea" or "master tamed," among other names. It has been used in folk medicine as a therapeutic agent due to its distinct pharmacological properties. Phytochemical studies have lead to the discovery of a wide range of biologically active substances produced in different parts of the plant (saponins, alkaloids, flavonoids, sulfates, tannins, coumarins, among others). Chemical analysis of the roots has revealed a great amount of sulfur derivatives, especially dibenzyl trisulfide (DTS), with antifungal, antibacterial, antioxidant and anticancer activities. In the view of evaluating the biotechnological production of DTS, this study aimed to optimize the in vitro culture of new callus lines, as well as suspension cells and somatic embryos, from in vitro plants of P. alliacea L., monitoring the biosynthetic capacity of the cultures. The results showed that the production of friable callus was obtained in leaf explants inoculated on MS medium supplemented with PIC or 2,4-D. In addition to the callogenic response, we observed the production of globular structures characterized as somatic embryos. The occurrence of direct somatic embryogenesis was confirmed by histological analysis of the regenerative process. The induction of somatic embryos gave rise to a secondary embryogenesis highly repetitive, until 150 days of culture and conversion to plants at a frequency of 5%. With respect to the cell suspension cultures from friable calluses, there was a decrease in cell growth during the subcultures. Suspension cultures derived from secondary embryogenic tissue maintained the repetitve process in liquid medium and displayed conversion rates lower than those obtained in solid medium. The development of whole plants from somatic embryos showed the possibility of using this system for the micropropagation of this species. The phytochemical assessment of the in vitro systems and plants kept in greenhouse conditions for 02 years showed significant differences, confirming that tissue culture may change the metabolic pathways. The gas chromatography / mass spectrometry performed with the dichloromethane extract of dried embryos and hexane extract of fresh embryos and dried roots of plants derived from somatic embryos showed the presence of DTS. Therefore, these cultures are considered important in vitro systems for the modulation of this substance.