Cryopreservation at −75°C of Agaricus subrufescens on wheat grains with sucrose

• Published in: Brazilian journal of microbiology 2018-04, Vol.49 (2), p.370-377
• Main Authors: Júnior, Lienine Luiz Zaghi, Lopes, Ana Daniela, Cordeiro, Fábio Aparecido, Colla, Itaruã Machri, Bertéli, Míria Benetati Delgado, Valle, Juliana Silveira do, Linde, Giani Andrea, Colauto, Nelson Barros
• Format: Article
• Language: English
• Subjects: Agaricus blazei; Agaricus subrufescens; Cereal grain; Colonies; Cryopreservation; Cryoprotectors; Dextrose; Freeze; Fungi; Genomes; Grain; MICROBIOLOGY; Monosaccharide; Mycelia; Potatoes; Preservation; Research Paper; Substrates; Sucrose; Sugar; Triticum; Viability; Wheat
• ISSN: 1517-8382; 1678-4405; 1678-4405
• DOI: 10.1016/j.bjm.2017.08.003

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.