原生质体融合构建高效降解苹果酸酿酒酵母

Construction of High Performance Malic Acid-reducing Yeast by Protoplast Fusion

为构建降解苹果酸能力强的酿酒酵母,采用原生质体融合技术对优良酿酒酵母(Saccharomy cescere-visiae)与解苹果酸裂殖酵母(Schizosaccharomyces malidevorans)进行属间融合。以双灭活原生质体为遗传标记筛选融合子,并对得到的融合子进行细胞体积、DNA含量方面的鉴定;对融合子进行降苹果酸性能、遗传稳定性、发酵性能和絮凝性测定,最终得到一株能稳定降解苹果酸高达31.7%的融合子Z29,该融合子连续15次传代,降酸性能稳定。Z29菌株发酵速度快,发酵度高,用其发酵的葡萄酒风味好,凝絮性强(本斯值为2.1)。

Decrement of the malic acid present in grapes is of considerable technological value in wine making because of great effect on the stabilization and flavor of the wine.The aim of this study is to make new strains which can reduce the malic acid in wine making.Intergeneric protoplast fusion technology has been used to construct hybrids between strains of saccharomyces cerevisae and schzosaccharomyces malidevorans.The fusions Z29 which has 31.7% malic acid degradation rate was tested in several aspects including cell morphology,genetic stability and the amount of chromosomal DNA,the fermentation ability and the flocculation capacity.High performance capillary electrophoresis(HPCE)was used to determine the degradation of the malic acid.The genetic stability was valued after 15 generations,showed that the degradation rate of malic acid and other features came from parental strains was stable.The fusion Z29 express fine properties came from parental strains in fermentation speed and the flocculation capacity with giving the wine fragrant flavour.