Solid-state fermentation as a tool for the culture of halophilic archaea: a practical experience for undergraduate students in biosciences

The cultivation of halophilic microorganisms has been widely reported in liquid and semi-solid media. However, there are few reports on the use of solid fermentation for their cultivation. In the present work, the extreme halophilic <i>Halobacterium</i> sp. NRC-1 (ATCC 700922) was cultured in solid medium using polyurethane as support and ATCC 2185 medium. The production of microorganisms was carried out using materials commonly available and accessible to any teaching laboratory by biotechnology engineering students (<i>n</i> = 40). The bioreactors used were borosilicate columns and 250 mL flasks with and without aeration, and archaeal growth was monitored at 600 nm. The present practical helped students understand the basics of solid fermentation for cultivating extreme halophilic microorganisms.