The objective of this study is to improve the production of L-DOPA from fungal source like Aspergillus terreus that can be further used to large-scale commercial production of this important drug from microbial source...The objective of this study is to improve the production of L-DOPA from fungal source like Aspergillus terreus that can be further used to large-scale commercial production of this important drug from microbial sources. L-DOPA, a dopamine precursor that can pass the blood-brain barrier, is presently the drug of choice for Parkinson's disease. Microbial production and isolation of L-DOPA from natural sources is yet to be achieved an economical process. In this study, the mycelial pellets ofAspergillus terreus 104 were entrapped in 2% calcium alginate and were studied for their capacity for L-3, 4-dihydroxyphenylalanine production. Results showed that the immobilized pellets produced L-DOPA to the extent of 0.74 mg·G^-1 biomass while the free pellets produced 0.8 mg·G^-1 biomass. Further, storage of immobilized pellets for 96 h at 4 ℃ resulted in the reduction of the original L-DOPA producing activity of the gel beads only 40% and that of free pellets lost completely. In order to improve the production yield, further experiments were designed. It was found that L-DOPA production could be prolonged with repeated batch wise use of immobilized mycelial pellets in calcium alginate retaining 80% of their L-DOPA producing capacity for a period of 72 h while free pellets lost completely within 24 h. Results of this kind therefore is interesting and promising for commercial scale production of L-DOPA from microbial sources.展开更多
文摘The objective of this study is to improve the production of L-DOPA from fungal source like Aspergillus terreus that can be further used to large-scale commercial production of this important drug from microbial sources. L-DOPA, a dopamine precursor that can pass the blood-brain barrier, is presently the drug of choice for Parkinson's disease. Microbial production and isolation of L-DOPA from natural sources is yet to be achieved an economical process. In this study, the mycelial pellets ofAspergillus terreus 104 were entrapped in 2% calcium alginate and were studied for their capacity for L-3, 4-dihydroxyphenylalanine production. Results showed that the immobilized pellets produced L-DOPA to the extent of 0.74 mg·G^-1 biomass while the free pellets produced 0.8 mg·G^-1 biomass. Further, storage of immobilized pellets for 96 h at 4 ℃ resulted in the reduction of the original L-DOPA producing activity of the gel beads only 40% and that of free pellets lost completely. In order to improve the production yield, further experiments were designed. It was found that L-DOPA production could be prolonged with repeated batch wise use of immobilized mycelial pellets in calcium alginate retaining 80% of their L-DOPA producing capacity for a period of 72 h while free pellets lost completely within 24 h. Results of this kind therefore is interesting and promising for commercial scale production of L-DOPA from microbial sources.