Diversidade de fungos endofíticos de clones de Paullinia cupana (Mart.) Ducke e avaliação de seus traços funcionais e potencial biotecnológico

Abstract

Endophytes are microorganisms that inhabit internal tissues of their hosts and can perform various ecological relationships without showing visible symptoms of infection. They produce compounds with different biotechnological applications and can benefit the host. This study aimed to characterize the endophytic fungi community of resistant and susceptible clones of Paullinia cupana (Mart.) Ducke and determine their role in promoting host resistance and biotechnological potential. Roots and seeds were sterilized and inoculated into plates with BDA and TSA culture media. The identification was carried out by partial sequencing of the ITS rDNA region. EtOAc extracts were prepared for evaluating potential antimicrobial, antioxidant, cytotoxic and phenolic content. EtOAc extracts were purified through CC and HPLC and compounds were elucidated by analysis of 1D and 2D NMR spectra and mass spectrometry. It was evaluated the production of hydrolytic enzymes, indole acetic acid (IAA) and fungicides, the endophytic ability and the association with mycorrhizal fungi (AMF) and dark septate (DSE). We isolated 256 strains of 33 species. Xylogone ganodermophthora showed higher relative frequency (30%). There was greater species diversity and higher colonization rate in the endophytic community of susceptible clones, Manaus environment, roots and PDA culture medium. Seventeen species with antimicrobial activity were found. The DPPH radical inhibition ranged from 0.14 to 85.37% and the phenolic content ranged between 0.022 and 0.861 mg GAE/mL. Five species reduced viability of tumor cells in more than 90%. Several species inhibited pathogenic fungi and produce hydrolytic enzymes and IAA. P. cupana is associated with DSE and FMA and the species P. asparagi (22TSA) and P. pinodella (28S) produce DSE structures. 3- hydroxypropionic acid was identified in D. phaseolorum. Therefore, communities are different in each clone, location and plant organ. Isolates have biotechnological potential and produce functional traits in vitro trat could benefit both susceptible and tolerant clones.