Saccharomyces eubayanusandSaccharomyces uvarumassociated with the fermentation ofAraucaria araucanaseeds in Patagonia

Abstract

Mudai is a traditional fermented beverage, made from the seeds of the Araucaria araucana tree by Mapuche communities. The main goal of the present study was to identify and characterize the yeast microbiota responsible of Mudai fermentation as well as from A. araucana seeds and bark from different locations in Northern Patagonia. Only Hanseniaspora uvarum and a commercial bakery strain of Saccharomyces cerevisiae were isolated from Mudai and all Saccharomyces isolates recovered from A. araucana seed and bark samples belonged to the cryotolerant species Saccharomyces eubayanus and Saccharomyces uvarum. These two species were already reported in Nothofagus trees from Patagonia; however, this is the first time that they were isolated from A. araucana, which extends their ecological distribution. The presence of these species in A. araucana seeds and bark samples, led us to postulate a potential role for them as the original yeasts responsible for the elaboration of Mudai before the introduction of commercial S. cerevisiae cultures. The molecular and genetic characterization of the S. uvarum and S. eubayanus isolates and their comparison with European S. uvarum strains and S. eubayanus hybrids (S. bayanus and S. pastorianus), allowed their ecology and evolution us to be examined.

Phylogeography of the wild Lager‐brewing ancestor (Saccharomyces eubayanus) in Patagonia

“…Incubation at 30 °C was applied mainly for Northern Patagonia samples ( N = 88), as well as a few Southern samples resulting in absence of yeast growth. Although previous studies in Patagonia (Libkind et al, ; Rodríguez et al, ) isolated a handful of S. eubayanus and Saccharomyces uvarum strains at 30 °C, the new samples did not yield any isolates. These results are consistent with the fact that S. eubayanus and S. uvarum are cryotolerant species that prefer cold habitats (Libkind et al, ).…”

“…In recent years, new strains of S. eubayanus have been isolated from North America, Asia and New Zealand, as well as Patagonia (Argentina) (Peris et al, , ; Rodríguez et al, ; Bing et al, ; Gayevskiy and Goddard, ), adding complexity to the phylogeography of this species. Population genomic studies have shown that two main populations with high genetic diversity exist in Patagonia (Patagonia A and Patagonia B/Holarctic, referred here as PA and PB/Hol respectively), as well as two divergent subspecies from Asia (Bing et al, ; Peris et al, ).…”

Saccharomyces eubayanus and Saccharomyces arboricola reside in North Island native New Zealand forests

“…Unsurprisingly given its name, this species has also been isolated from cider (Coton et al ., ), sherry (Esteve‐Zarzoso et al ., ) and wine (Ganga and Martinez, ) fermentations worldwide indicating it is widespread, but the phylogeography of this species is not described. The remaining yeast species identified was K. servazzii and has been found in South America on Araucaria araucana seeds (Rodríguez et al ., ), and been isolated from sourdough (Di Cagno et al ., ) and kimchi (Kobayashi et al ., ) fermentations, as well as on wine grapes in Denmark (Lederer et al ., ). Unsurprisingly given the ethanol selection pressure in the isolation media, all three genera found are known to be Crabtree positive (Hagman et al ., ).…”

Improved cider fermentation performance and quality with newly generated Saccharomyces cerevisiae × Saccharomyces eubayanus hybrids

“…This may be either caused by the high sporulation capacity of S. eubayanus [48] that resulted in a spore of C902 mating with S. cerevisiae 59A, or by loss of chromosomes post-hybridization due to chromosome instability and even incompatibility. Examples of the latter are the chromosome III from S. cerevisiae that has high loss frequency [28] and the chromosome XII from S. bayanus being partially incompatible with the S. cerevisiae genome [30].…”