Brazilian Journal of Microbiology Brazilian Journal of Microbiology
Braz J Microbiol 2018;49:370-7 - Vol. 49 Num.2 DOI: 10.1016/j.bjm.2017.08.003
Biotechnology and Industrial Microbiology
Cryopreservation at −75°C of Agaricus subrufescens on wheat grains with sucrose
Lienine Luiz Zaghi Júnior, Ana Daniela Lopes, , Fábio Aparecido Cordeiro, Itaruã Machri Colla, Míria Benetati Delgado Bertéli, Juliana Silveira do Valle, Giani Andrea Linde, Nelson Barros Colauto
Universidade Paranaense, Programa de Pós-graduação em Biotecnologia Aplicada à Agricultura, Umuarama, PR, Brazil
Received 23 February 2017, Accepted 04 August 2017
Abstract

Agaricus subrufescens is a basidiomycete which is studied because of its medicinal and gastronomic importance; however, less attention has been paid to its preservation. This study aimed to evaluate the effect of sucrose addition to substrate and cryotube on the viability of Agaricus subrufescens cryopreserved at −20°C and at −75°C for one and two years. Zero, 10% or 20% sucrose was added to potato dextrose agar or wheat grain. The mycelia were cryopreserved in the absence of cryoprotectant or with sucrose solutions at 15%, 30% or 45%. After one or two years at −75°C or at −20°C, mycelia were thawed and evaluated about viability, initial time of growth, colony diameter and genomic stability. Cryopreservation at −20°C is not effective to keep mycelial viability of this fungus. Cryopreservation at −75°C is effective when sucrose is used in substrates and/or cryotubes. Without sucrose, cryopreservation at −75°C is effective only when wheat grains are used. Physiological characteristic as mycelial colony diameter is negatively affected when potato dextrose agar is used and unaffected when wheat grain is used after two-year cryopreservation at −75°C. The fungus genome does not show alteration after two-year cryopreservation at −75°C.

Keywords
Preservation, Freeze, Cereal grain, Monosaccharide, Agaricus blazei
Braz J Microbiol 2018;49:370-7 - Vol. 49 Num.2 DOI: 10.1016/j.bjm.2017.08.003