This study evaluated D-xylose-assimilating yeasts that are associated with rotting wood from the Galápagos Archipelago, Ecuador, for xylitol production from hemicellulose hydrolysates. A total of 140 yeast strains were isolated. Yeasts related to the clades Yamadazyma, Kazachstania, Kurtzmaniella, Lodderomyces, Metschnikowia and Saturnispora were predominant. In culture assays using sugarcane bagasse hemicellulose hydrolysate, Candida tropicalis CLQCA-24SC-125 showed the highest xylitol production, yield and productivity (27.1 g L(-1) xylitol, Y p/s (xyl) = 0.67 g g(-1), Qp = 0.38 g L(-1). A new species of Cyberlindnera, strain CLQCA-24SC-025, was responsible for the second highest xylitol production (24 g L(-1), Y p/s (xyl) = 0.64 g g(-1), Qp = 0.33 g L(-1) h(-1)) on sugarcane hydrolysate. The new xylitol-producing species Cyberlindnera galapagoensis f.a., sp. nov., is proposed to accommodate the strain CLQCA-24SC-025(T) (=UFMG-CM-Y517(T); CBS 13997(T)). The MycoBank number is MB 812171.

Twenty-four yeast strains were isolated from ephemeral flowers of Ipomoea spp. and Datura sp. and their associated insects in the Galápagos Archipelago, Ecuador, and from Ipomoea spp. and associated insects in the Cameron Highlands, Malaysia. Sequences of the D1/D2 domains of the large subunit rRNA gene indicated that these strains belong to a novel yeast species of the Kodamaea clade, although the formation of ascospores was not observed. The closest relative is Candida restingae. The human-mediated dispersion of this species by transpacific contacts in ancient times is suggested. The name Kodamaea transpacifica f.a., sp. nov. is proposed to accommodate these isolates. The type strain is CLQCA-24i-070T ( = CBS 12823T = NCYC 3852T); MycoBank number MB 803609.

Chicha, a type of beer made mainly with maize or cassava, is a traditional fermented beverage of the Andean region. There have only been a few studies on yeasts associated with chicha fermentation, and the species diversity occurring during the production of this beverage is not known. The objective of this study was to determine the biodiversity of yeasts in chicha, and to characterize the Saccharomyces cerevisiae populations associated with the production of chicha de jora, seven-grain chicha, chicha de yuca, and chicha de morocho in Ecuador. The molecular diversity of S. cerevisiae populations was determined by restriction polymorphism mitochondrial profiles. The beverages were characterized based on their physicochemical parameters. Twenty-six species were identified, and the most prevalent species were S. cerevisiae and Torulaspora delbrueckii. Other yeast species were isolated at low frequencies. Among 121 isolates of S. cerevisiae, 68 different mtDNA molecular profiles were identified. These results showed that chichas are fermented by a high number of different strains of S. cerevisiae. Some other species provided a minor contribution to the fermentation process. The chicha presented generally similar physicochemical parameters to those observed for other traditional fermented beverages, and can be considered as an acid fermented beverage.

Wickerhamomyces arborarius f.a., sp. nov., an ascomycetous yeast species found in arboreal habitats on three different continents The ascomycetous genus Wickerhamomyces was created, along with two other genera (Barnettozyma and Lindnera), following a recent detailed phylogenetic study carried out by Kurtzman et al. (2008) of 140 coenzyme Q-7 producing yeast taxa. The aim of the study was to determine the phylogenetic placement of species (and species varieties) assigned to the genera Issatchenkia, Pichia, Starmera and Williopsis. Using a multigene sequencing approach, Kurtzman and colleagues were able to resolve these species into five distinct and well-supported clades. As a result, the genus Pichia underwent a significant reduction in overall size (to just 20 species) and was redefined and restricted to only those species closely related to Pichia membranifaciens (Pichia membranifaciens clade), including all those previously assigned to the genus Issatchenkia. Pichia dryadoides and Pichia quercuum were both transferred, as basal members, to the genus Starmera (Starmera clade). The three remaining clades, each comprising a varied number of Pichia and Williopsis species, were recognized as representing new genera, and were named Barnettozyma, Lindnera and Wickerhamomyces.When first created, sixteen Pichia species, including the former Pichia anomala (renamed as Wickerhamomyces anomalus) and Pichia sydowiorum (renamed as Wickerhamomyces Abbreviation: ITS, internal transcribed spacer.The GenBank/EMBL/DDBJ accession numbers for the LSU D1/D2 and ITS sequences of CLQCA 10-161 T are FN908198 and FR670785, respectively. The accession number for the LSU D1/D2 sequence of GY7L12 is FJ527096.The MycoBank number for Wickerhamomyces arborarius f.a., sp. nov.

Seven strains representing a novel yeast species belonging to the genus Kazachstania were found at several collection sites on both mainland Ecuador (Yasuní National Park) and the Galá pagos (Santa Cruz Island). Two strains (CLQCA 20-132 T and CLQCA 24SC-045) were isolated from rotten wood samples, two further strains were isolated from soil samples, and three strains were isolated from decaying fruits. Sequence analyses of the D1/D2 domains of the LSU rRNA gene and ribosomal internal transcribed spacer (ITS) region indicated that the novel species is most closely related to Kazachstania servazzii and Kazachstania unispora. Although the strains could not be distinguished from one another based upon their differing geographical origins, they could be differentiated according to their isolation source (fruit, soil or wood) by ITS sequencing. The species name Kazachstania yasuniensis sp. nov. is proposed to accommodate these strains, with CLQCA 20-132 T (5CBS 13946 T 5NCYC 4008 T ) designated the type strain.>The genus Kazachstania was first proposed by Zubkova in 1971 with the description of Kazachstania viticola, a yeast isolated from fermenting grapes in Kazachstan . Later in the same decade, the taxonomic status of Kazachstania viticola was reassessed by Von Arx et al. (1977), and it was considered to be a synonym of Saccharomyces dairenensis. However, the genus was reintroduced and redefined in 2003(Kurtzman, 2003 to accommodate Kazachstania viticola (type species) and 19 other species from the genera Arxiozyma, Kluyveromyces, Pachytichospora and Saccharomyces (sensu lato). This resulted from a detailed multigene sequence analysis carried out by Kurtzman & Robnett (2003) to examine the phylogenetic relationships and genus boundaries of the approximately 80 species belonging to the 'Saccharomyces complex'. In the most recent (fifth) edition of The Yeasts, A Taxonomic Study, 32 species were listed as belonging to the genus (Vaughan-Martini et al., 2011). Since then, the genus has continued to increase in size as additional species have been discovered and described including Kazachstania bromeliacearum, Kazachstania ichnusensis, Kazachstania intestinalis, Kazachstania pyschrophila, Kazachstania rupicola, Kazachstania taianensis and Kazachstania wufongensis (Lee et al., 2009;Chen et al., 2010;Suh & Zhou, 2011;Araú jo et al., 2012;Cardinali et al., 2012; Kabisch et al., 2013; Safar et al., 2013).On the basis of multigene sequencing, using both nuclearand mitochondrial-encoded genes, Kurtzman & Robnett (2003) resolved the genus into three main lineages (see Fig. 1 of Kurtzman & Robnett, 2003). However, with only Abbreviations: ITS, internal transcribed spacer; Si, relative specialization index.The GenBank/EMBL/DDBJ accession numbers for the LSU D1/D2 sequences of strains CLQCA 20-132 T , CLQCA Here we describe the discovery of seven novel strains representing the genus Kazachstania isolated at separate sites on mainland Ecuador and in the Galápagos archipelago, and provide a formal taxonomic description of a ...