利用固定化分裂酵母菌進行蘋果酸酒精醱酵

Abstract

利用Schizosaccharomyces pombe TMB 1138固定於Calccium alginate之膠體上，進行蘋果酸酒精醱酵。含2.0×107之細胞懸浮液4 ml，包埋於Sodium alginate水溶液中，以製成2％ Na-alginate（w/v），然後逐滴加入0．1M CaCl2溶液中，膠體在室溫下靜置3?4小時，便形成2％ Ca-alginate，直徑約?4 mm。 以葡萄汁在28℃下活化24小時後，取300顆膠體加入醱酵用培養基，內含L-malic acid 10 mg/ml, Na-citrate 0.1M和Na-phosphate 0.2M, pH值?3.50。於25℃或28℃下振盪醱酵24小時後，可將培養基內的蘋果酸完全利用，並可使總酸度降低。固定化分裂酵母菌在37℃的高溫下，亦有很高的醱酵能力；且對酒精具有抗性，其濃度至少可達15％（v/v）。 同樣條件下作分批式醱酵，在醱酵用培養基中可維持於97％以上的蘋果酸利用率達7天之久；而在葡萄汁中維持4天85％的利用率；在白葡萄酒中，亦可維持4天87％的利用率。以白葡萄酒作連續醱酵時，24小時後可達92％的蘋果酸利用率，而後9天中維持75％。

Schizosaccharomyces pombe TMB 1138 was immobilized in calcium alginate beads for use in the malo-alcoholic fermentation. A 4 ml cell suspension containing about 2.0 x 107 cells was entrapped into sodium alginate solution in order to prepare 2% Na-alginate (w/v), and then added drops to 0.1 M CaCl2 solution; the beads were allowed to stand at room temperature for 3-4 hrs to form 2% Ca-alginate, the diameter of bead was about 4 mm. After activation by incubation at 28℃ for 24 hrs in grape juice, 300 beads of immobilized cells were inoculated into fermentation medium containing 10 mg/ml L-malic acid, 0.1 M sodium citrate and 0.2 M sodium phosphate, pH 3.50. After fermentation at 25℃ or 28℃ for 24 hrs by shaking, it could utilize L-malic acid completely and reduce the total acidity. The immobilized cells also had high malo-alcoholic fermentation activity at higher temperature (37℃) and was quite resistant to alcohol even at 15% (v/v). Under the same condition for batch fermentation, it was found that the utilization of L-malic acid was over 97% for 7 days in fermentation medium, 85% for 4 days in grape juice and 87% for 4 days in wine. Additionally, for the continuous fermentation in wine, the utilization of L-malic acid reached up to 92% at 24 hrs and maintained at 75% in the later 9 days.