台灣北部沿海酵母菌之分離及特性研究

Abstract

本研究於2009年8月間，在台灣北部沿海採集四個樣點的水樣，利用GPYS-TC固態培養基加以進行分離、純化後，一共分離出二十六株酵母菌，將分離株的5.8S–ITS rDNA 區域片段定序，並藉由National Center for Biotechnology Information (NCBI)網站內序列比對，結果顯示二十六株酵母菌分別屬於Pichia, Candida, Cryptococcus, Rhodotorula, Issatchenkia五個屬，進一步探討分離株的生長特性、生理特性、菌落的形態以及26S rDNA D1/D2區域片段序列後，初步判定B4、C2、D1與D7分別為Cryptococcus liquefaciens、Cryptococcus flavus、Issatchenkia orientalis、Rhodotorula mucilaginosa，而D17、A4、A5、A1、D3、B2與C3七株分離株則可能為新種酵母菌；另外，各群代表株均具有葡萄糖發酵產乙醇的能力，其中，分離株D3在GY100培養基培養60小時有最高乙醇產率25.3 g/L，但在24小時，有每小時最高乙醇轉換率0.72%。

Twenty six yeast strains were isolated from four sampling sites of north Taiwan in August ,2009. According to 5.8S–ITS rDNA sequence analyses by NCBI GeneBank, these strains could be divided into nine genotypes. The results indicate that these twenty six yeast strains could be belonged to Pichia, Candida, Cryptococcus, Rhodotorula and Issatchenkia, respectively. In polyphasic studies, such as physiological and biochemical characteristics and 26S rDNA D1/D2 sequence analyses, these four representative strains, B4, C2, D1and D7 were blonged to Cryptococcus liquefaciens, Cryptococcus flavus, Issatchenkia orientalis and Rhodotorula mucilaginosa, respectively. D17, A4, A5, A1, D3, B2 and C3 should be classified into novel species. D3, the highest ethanol production efficiency strain, could produce 25.3 g/L ethanol in GY100 broth in 60 hours. In 24 hours, the highest ethanol conversion rate of D3 was 0.72% per hour.