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International audience; Analysis of yeasts isolated from various biotopes in French Guiana led to the identification of two strains isolated from flowers and designated CLIB 1634(T) and CLIB 1707(T). Comparison of the D1/D2 domain of the large subunit (LSU D1/D2) rRNA gene sequences of CLIB 1634(T) and CLIB 1707(T) to those in the GenBank database revealed that these strains belong to the Starmerella Glade. Strain CLIB 1634(T) was shown to diverge from the closely related Starmerella apicola type strain CBS 2868 T with a sequence divergence of 1.34 and 1.30 %, in the LSU D1/D2 rRNA gene and internal transcribed spacer (ITS) sequences respectively. Strain CLIB 1634(T) and Candida apicola CBS 2868(T) diverged by 3.81 and 14.96 % at the level of the protein-coding gene partial sequences EF-1 alpha and RPB2, respectively. CLIB 1707(T) was found to have sequence divergence of 3.88 and 9.16 % in the LSU D1/D2 rRNA gene and ITS, respectively, from that of the most closely related species Starmerella ratchasimensis type strain CBS 10611(T). The species Starmerella reginensis f.a., sp. nov. and Starmerella kourouensis f.a., sp. nov. are proposed to accommodate strains CLIB 1634(T) (=CBS 15247(T)) and CLIB 1707(T) (=CBS 15257(T)), respectively.

Despite the increasing importance of palm wines as a key element in Ivorian socio-cultural practices, and the high involment of yeasts in the production of these beverages, no studies have been devoted to aroma production of yeasts and their potential uses in biotechnological applications. In this work, aroma profiles of 20 non pathogenic yeast strains (11 from raffia and 9 from ron, representing 13 species) among the 21 yeasts isolated were established using HS–SPME–GC/MS analysis. A total of 50 Volatile Organic Compounds (VOCs) produced by these yeasts were identified and grouped into five main families, namely higher alcohols, aldehydes, ketones, organic acids and esters. Among these VOCs, esters were the most abundant (28 compounds). Some strains produced specific compounds of technological interest which could be used for diverse applications, such as beverages, ice creams, baked goods and desserts and synthetic flavouring ingredient. Among them, Hanseniaspora jakobsenii CLIB 3083 produced the highest number of VOCs.

International audience; Aims To investigate the genotypic diversity and enzymatic activity of yeast flora isolated from spontaneous fermenting saps of various palm trees (Borassus aethiopum, Raphia hookeri, Elaeis guineensis) tapped for palm wines. Methods and Results PCR-restriction fragment length polymorphism of ITS-5.8S rDNA combined to 26S rRNA gene and/or the partial ACT1 gene sequencing were applied for yeast characterization, and their enzymatic profiles assessed by using API ZYM kits. Thirteen genera and 23 species were identified, with the highest diversity (14 species) in raffia wine. Saccharomyces cerevisiae was dominant and common to all palm wines. Some potentially pathogenic yeasts were also isolated. The majority of tested strains displayed high amylo-peptidase, phosphatase, beta-glucosidase and alpha-glucosidase activities and esterase activity. Conclusions Diverse yeast species colonized palm wines, among which some were related to a specific type of wine and the majority of them have the ability to digest starch, sugar, protein or lipid. Significance and Impact of the Study This study is a first step in understanding the significance of indigenous yeast flora of palm wines from Cote d'Ivoire. This knowledge is important as a tool for establishing new indigenous yeast collection; which could be used for the product quality improvement and as enzyme sources for biotechnological purposes.