d-Xylose fermentation, xylitol production and xylanase activities by seven new species of Sugiyamaella

Sixteen yeast isolates identified as belonging to the genus Sugiyamaella were studied in relation to D-xylose fermentation, xylitol production, and xylanase activities. The yeasts were recovered from rotting wood and sugarcane bagasse samples in different Brazilian regions. Sequence analyses of the internal transcribed spacer (ITS) region and the D1/D2 domains of large subunit rRNA gene showed that these isolates belong to seven new species. The species are described here as Sugiyamaella ayubii f.a., sp. nov. (UFMG-CM-Y607(T) = CBS 14108(T)), Sugiyamaella bahiana f.a., sp. nov. (UFMG-CM-Y304(T) = CBS 13474(T)), Sugiyamaella bonitensis f.a., sp. nov. (UFMG-CM-Y608(T) = CBS 14270(T)), Sugiyamaella carassensis f.a., sp. nov. (UFMG-CM-Y606(T) = CBS 14107(T)), Sugiyamaella ligni f.a., sp. nov. (UFMG-CM-Y295(T) = CBS 13482(T)), Sugiyamaella valenteae f.a., sp. nov. (UFMG-CM-Y609(T) = CBS 14109(T)) and Sugiyamaella xylolytica f.a., sp. nov. (UFMG-CM-Y348(T) = CBS 13493(T)). Strains of the described species S. boreocaroliniensis, S. lignohabitans, S. novakii and S. xylanicola, isolated from rotting wood of Brazilian ecosystems, were also compared for traits relevant to xylose metabolism. S. valenteae sp. nov., S. xylolytica sp. nov., S. bahiana sp. nov., S. bonitensis sp. nov., S. boreocarolinensis, S. lignohabitans and S. xylanicola were able to ferment d-xylose to ethanol. Xylitol production was observed for all Sugiyamaella species studied, except for S. ayubii sp. nov. All species studied showed xylanolytic activity, with S. xylanicola, S. lignohabitans and S. valenteae sp. nov. having the highest values. Our results suggest these Sugiyamaella species have good potential for biotechnological applications.