Isolation, Identification and Characterization of a Antidementia Acetylcholinesterase Inhibitor-Producing Yarrowia lipolytica S-3

This report describes the isolation and identification of a potent acetylcholinesterase (AChE) inhibitor-producing yeasts. Of 731 species of yeast strain, the S-3 strain was selected as a potent producer of AChE inhibitor. The selected S-3 strain was investigated for its microbiological characteristics. The S-3 strain was found to be short-oval yeast that did not form an ascospore. The strain formed a pseudomycelium and grew in yeast malt medium containing 50% glucose and 10% ethanol. Finally, the S-3 strain was identified by its physiological characteristics and 26S ribosomal DNA sequences as Yarrowia lipolytica S-3.

Production of the Acetylcholinesterase Inhibitor from Yarrowia lipolytica S-3

The acetylcholinesterase (AChE) inhibitor of Yarrowia lipolytica S-3 was maximally produced when it was incubated at 30degrees C for 36 h in an optimal medium containing 1% yeast extract, 2% peptone and 2% glucose, with an initial pH 6.0. The final AChE inhibitory activity under these conditions was an IC50 value of 64 mg/ml. After partial purification of the AChE inhibitor by means of systematic solvent extraction, the final IC50 value of the partially purified AChE inhibitor was 0.75 mg/ml. We prepared a test product by using the partially purified AChE inhibitor and then determined its stability for the development of a new antidementia commercial product. The test product was stable at room temperature for 15 weeks.