Flammulina velutipes: An option for “alperujo” use

RUGOLO, MAXIMILIANO; LEVIN, LAURA; LECHNER, BERNARDO ERNESTO

REVISTA IBEROAMERICANA DE MICOLOGIA

ASOCIACION ESPANOLA MICOLOGIA-AEM

Año: 2016 vol. 33 p. 242 - 247

1130-1406

Background Two-phase olive-mill wastes (or ?alperujo?) exhibit highly phytotoxic properties, mainly due to phenols. A valuable option for alperujo is its agricultural use, provided that no phytotoxic effects occur. Aims The present investigation was aimed at evaluating the efficacy of two strains of the lignin-degrading fungus Flammulina velutipes to colonize alperujo in order to produce edible mushrooms and to achieve its detoxification. Methods Some important cultural characters related to mushroom production (earliness, biological efficiency and quality of basidiomes) were estimated. The production of lignocellulolytic enzymes, phenol removal and detoxification of the substrate was evaluated. Results High biological efficiencies (70.8%) were obtained at 12 °C with F. velutipes strain BAFC 670/06 in a substrate containing poplar wood shavings and 90% of alperujo. The nature of the substrate did not seem to exert an important influence on pileus and stem morphology; nevertheless shortest stems were observed at higher temperatures. Endo-β-1,4-glucanase, endo-β-1,4-xylanase, laccase and Mn-peroxidase activities were detected in the extracts recovered from the solid-state cultures. Both F. velutipes strains were effective in removing the phenolic compounds. The initial concentration in the substrate with 90% alperujo was reduced in the case of F. velutipes BAFC 1763 by 84.31%, and 40.15% by F. velutipes BAFC 670/06. Germinability experiments on Raphanus sativus, showed that alperujo phytotoxicity was significantly reduced by F. velutipes cultures. Conclusions The experimented changes by the spent mushroom substrate resulting from F. velutipes cultivation with high amount of alperujo would allow its reuse for agricultural purposes.