Article

Transformation of L-tyrosine to L-dopa by a novel fungus, Acremonium rutilum, under submerged fermentation.

Department of Microbiology, Gulbarga University, Gulbarga, India.
Current Microbiology (impact factor: 1.82). 02/2009; 58(2):122-8. DOI:10.1007/s00284-008-9287-5
Source: PubMed

ABSTRACT The present study deals with the transformation of L-tyrosine to L-dopa by Acremonium rutilum, a fungal tyrosinase producer, isolated from decomposed banana stud. This appears to be the first report on A. rutilum as a polyphenoloxidase producer with both cresolase and catecholase activity. Enriched Czapek-Dox agar was used for plate assay screening. Enriched potato dextrose broth was used for optimization studies, which induced high levels of L-dopa under submerged fermentation. A. rutilum gave the maximum L-dopa production (0.89 mg/ml) and tyrosinase activity (1095 U/mg) under the optimized parameters, that is, a temperature of 25 degrees C, pH 5.5, an inoculum size of 2.5 ml, and an incubation time of 72-120 h, with L-tyrosine (5 mg/ml) as substrate. Five resolved bands, with R(f) values of 0.73, 0.60, 0.54, 0.37, and 0.26, were observed, which confirmed the presence of L-dopa. This study involves the elevated profile of L-dopa production. Such study is needed, as L-dopa has the ability to control Parkinson's disease.

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    Article: Biotechnological production of l-tyrosine and derived compounds
    María I Chávez-Béjar, José L Báez-Viveros, Alfredo Martínez, Francisco Bolívar, Guillermo Gosset
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Keywords

25 degrees C
 
bands
 
catecholase activity
 
control Parkinson's disease
 
decomposed banana stud
 
Enriched potato dextrose broth
 
first report
 
fungal tyrosinase producer
 
incubation time
 
inoculum size
 
optimization studies
 
optimized parameters
 
plate assay screening
 
substrate
 
tyrosinase activity
 

R Krishnaveni