构建直接发酵淀粉产生酒精的酵母融合菌株的研究

以酒精酵母和热带假丝酵母为亲本，通过单亲灭活原生质体融合技术，获得了既具有糖化酶活性又能高产酒精的稳定的酵母融合株，并测定和比较了融合子的细胞大小、DNA含量以及比增长率μ、淀粉利用能力、乙醇耐受性、α-淀粉酶和糖化酶活力等生产性能。属间原生质体融合率为9.2×10^-6。F1和F5两株融合子性状较好，酒精发酵产量可达8.8%和11.5%，具有良好的应用前景。

Construction of Yeast Fusants of Directly Transform Starch into Ethanol

To obtain strains that are able to efficiently produce ethanol directly from starchy material, we have used the protoplast fusion technique to construct hybrids between Saccharomyces cerevisiae and Candida tropicalis. The isolation of fusants used a selective system by a irreversible biochemical inhibitor-Iodoacetic Acid(ID), and the fusion frequency was 9.2 x 10(-6). The cell size and DNA content of the fusants were determined. Through testing some productive properties such as specific growth rate, saccharification ability, ethanol tolerance and the activities of alpha-amylase, saccharogen amylase, we selected two fusants--F-1 and F-5. They were more superior and their ethanol production came up to 8.8% and 11.5%.