固定化酵母细胞转化肉桂酸生产L-苯丙氨酸

Production of L-phenylalanine by biotransformation of cinnamic acid using immobilized whole Rhodotorula glutinis cells

建立了一套较之传统方法更为准确的测定固定化细胞生产L-苯丙氨酸(L-phe)的新方法,采用高效液相色谱法(HPLC)测定反复冲洗凝胶所得冲洗液可以更准确地测定L-phe的生成,并采用新方法研究了固定化黏红酵母细胞的活力与稳定性。复合凝胶聚乙烯醇(PVA)+琼脂糖为最适载体,最佳质量浓度为PVA 120 g/L、琼脂糖10 g/L,反复冻融4次。此法得到的固定化细胞颗粒,机械强度良好,酶活保持时间长达200 h,L-苯丙氨酸产量高。通过流化床反应器测定其半衰期为100 h,200 h后总产量为44.58 mg/10 mL,固定化细胞无崩解现象。

The new method which was more accurate than traditional way of determination immobilized cells to produce L-phenylalanine（L-phe） was used. Using high performance liquid chromatography （HPLC） to determine repeated washing fluid can gain the data of L-phe more accurate. The activity and stability of immobilized Rhodotorula glutinis cells using new method were studied. The plural gel（polyvinyl alcohol and agarose） was the optimum gel whose optimal concentration were PVA 120 g/L, agarose 10 g/L, repeated freezing and thawing 4 times. The beads prepared by these methods which had a high yield of L-phenylalanine were so strong mechanically and activity maintained for 200 hours. Through the fluidized bed reactor half-life was 100 h, after 200 h the total yield was 44.58 mg/10 mL. No disruption of the gel beds were observed.