Genetic diversity of non-Saccharomyces yeasts associated with spontaneous fermentation of Cabernet Sauvignon wines from Ningxia, China.

The organoleptic profile and quality of wine are affected by the presence of different non-Saccharomyces species and strains. Therefore, the identification and characterization of non-Saccharomyces yeasts are the first step to understand their function, and to develop a better strain selection program for winemaking. This study investigated the biodiversity of non-Saccharomyces yeasts associated with spontaneous fermentation of Cabernet Sauvignon wines from five sub-regions (Shi Zuishan, Yinchuan, Yu Quanying, Qing Tongxia and Hong Sibu) in Ningxia, China. Yeast species were identified by sequencing the 26S rRNA D1/D2 region, and strains at the subspecies level were discriminated using tandem repeat-tRNA (TRtRNA) PCR analysis. A total of 524 yeast colonies were isolated, and 19 non-Saccharomyces yeast species belonging to 10 genera were identified, including Aureobasidium pullulans, Cryptococcus albidus, Cryptococcus sp., C. flavescens, C. terrestris, C. magnus, Cystofilobasidium ferigula, Candida zemplinina, Filobasidium magnum, Filobasidium sp., F. elegans, Hanseniaspora uvarum, Metschnikowia pimensis, M. pulcherrima, Naganishia albida, Pichia kluyveri, P. kudriavzevii, Rhodotorula glutinis and R. graminis. Hanseniaspora uvarum, C. zemplinina, and M. pulcherrima were the three most dominated species, while other non-Saccharomyces species were only present in the early stage of spontaneous fermentations at different levels. Further, for the yeast discrimination at strain level, 34 profiles were obtained by amplification with primer pairs TtRNASC/5CAG, while 40 profiles were obtained with primer pairs TtRNASC/ISSR-MB. This study explored the diversity of non-Saccharomyces species in Ningxia, China, and made an important contribution of genetic resources for further strain development.

The complete chloroplast genome sequence of the medicinal plant Stephania epigaea H. S. Lo, 1978 (Menispermaceae) from Yunnan, China.

Stephania epigaea H. S. Lo, 1978 is a medicinal plant commonly used in southwest China. This study characterized the first complete chloroplast (cp) genome sequence of this species. The complete cp was 157,738 bp in length, containing a large single-copy region (LSC) of 88,460 bp, a small single-copy region (SSC) of 19,778 bp, and a pair of inverted repeat regions (IRs) of 24,750 bp. It encoded 130 genes, including 85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The GC content of the complete genome was 36.7%. Phylogenetic analysis of complete cp sequences revealed that S. epigaea was clustered with S. japonica from the Menispermaceae family.

Characterization of the complete chloroplast genome of Salvia tiliifolia Vahl (Lamiaceae).

Salvia tiliifolia Vahl is native to Central America and considered as an invasive plant in Mexico, the United States, Ethiopia, South Africa, and Australia. The complete chloroplast (cp) genome of S. tiliifolia was 150,836 bp in length, which contained a large single-copy (LSC) region of 82,129 bp, a small single-copy (SSC) region of 17,533 bp, and a pair of inverted repeats (IRs) region of 25,587 bp each. The genome harbored 130 genes, including 85 protein coding genes, 37 tRNA genes, and 8 ribosomal RNA genes. The overall GC content was 37.99%. Phylogenetic analysis indicated that S. tiliifolia is closely related to the species of Salvia chanryoenica.