L-苯丙氨酸生产中PAL酶活及产酸因素的研究

PAL activity and productivity of L-phenylalanine in the production of L-phenylalanine

研究了诱导剂、表面活性剂及酶稳定剂对L 苯丙氨酸解氨酶 (PAL酶 )酶活的影响 ,考察了细胞量及反式肉桂酸的流加对产酸的影响。结果表明 :以 0 0 5 %L 苯丙氨酸为诱导剂可提高酶活 18 2 %,以 0 0 0 5 %溴化十六烷基吡啶为表面活性剂可提高酶活 12 4 %,PAL酶的稳定剂 2mol/L山梨醇与 0 1%戊二醛的组合可使酶活提高 94 5 %。细胞量 /肉桂酸比率α为 3 6对产酸最有利 ,在第 3,2 5 ,40h流加反式肉桂酸至浓度为 0 1mol/L ,可提高产酸浓度9 6 %。实验发现野生菌株的产酸能力可达 10 0 3g/L ,肉桂酸的转化率可达 6 0 %。

The effects of several PAL inducers, permeabilizing agents and PAL stabilizing agents on the PAL activity, and the effects of cell loading and fed-batch addition of trans-cinnamic acid on the production of L-Phenylalanine were studied. The results show that 0.05% L-Phe as a PAL inducer can increase PAL activity by 18.2% and 0.005% cetylpyridinium chloride as a permeabilizing agent can increase the PAL activity by 12.4%, and 0.1% glutaraldehyde and 2?mol/L sorbitol a combination of stabilizing agents can increase the PAL activity by 94.5% as. The appropriate cell loading was ca.3.6. Adding trans-cinnamic acid to the concentration of 0.1?mol/L at the 3?rd,25?th and 40th hour could increase the concentration of L-Phenylalanine by 9.6%. Under the conditions of our experiments, a maximum concentration of 10.03g/L L-Phenylalanine and a maximum conversion rate of 60% trans-cinnamic acid were obtained with the wild strain of Rhodotorula glutinis.