Partial Purification and Characterisation of Alcohol Dehydrogenase from <i>Acetobacter aceti</i> Isolated from Palm Wine

• Main Authors: Donatus Chimaobi ONAH, Sabinus Oscar O. EZE, Patrick Emeka ABA
• Format: Article
• Language: English
• Published: University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca 2016-06-01
• Series: Notulae Scientia Biologicae
• Online Access: http://www.notulaebiologicae.ro/index.php/nsb/article/view/9810
• ISSN: 2067-3205; 2067-3264

Palm wine is a very important alcoholic beverage whose consumption is limited because it spoils easily. The study was designed to isolate Acetobacter aceti from palm wine, then extract, purify and characterize alcohol dehydrogenase (AD) from the A. aceti. Muller Hilton agar was used as medium for the growth of A. aceti for 48 h. The cells were harvested and subjected to ultrasonication using 500 watt ultrasonicator. Enzyme assay was carried out in both the supernatant and pellet. The enzyme was precipitated by polyethelene glycol 6000 while gel filtration was used for purifying the enzyme. The effects of pH, temperature and substrate concentration on AD were evaluated. The isolated A. aceti was gram negative, rod shaped, catalase positive, oxidase negative and was able to oxidize acetic acid to CO2 and H2O. Triton X-100 (0.3%) was the most effective concentration in solubilizing the protein (AD), while 15% polyethelene glycol 6000 was the most effective concentration for the precipitation of AD. An optimal pH of 5 was obtained with an optimal temperature of 50 °C. The most appropriate to solubilize and precipitate AD were 0.3% triton X-100 and 15% polyethelene glycol 6000 respectively, while AD activity was reduced under acidic pH, as well as for low and high temperatures.