Optimization of three-phase cell disruptor for the release of alcohol dehydrogennase from disrupted baker's yeast

• Main Authors: Huang Yung-Nien, 黃永年
• Other Authors: Chang Yu-Kaung
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/50528798578035861669

碩士 === 明志科技大學 === 生化工程研究所 === 97 === In this study, three-phase cell disruptor was used to disrupted the baker’s yeast cells. The disruption efficiency was evaluated by release of alcohol dehydrogenase (ADH) and converted into the productivity of ADH (U/ming). The optimization of cell disruption was performed with 500 μm glass bead at 4℃ by using response surface methodology. The experimental operating conditions included agitation rate (1,000-5,000 rpm), cell concentration (30-70% w/v), glass beads-volume (750-1,750 ml), disruption time (5-15 time), and gas rate (10-30 L/ml). The aim of the work was to find the values of process variables to achieve the maximal productivity of ADH. It was found that agitation rate, cell concentration, and glass beads-volume were the significant factors. The experiments of paths of steepest ascent based on the first-order model were constructed under the conditions (i.e. agitation rate of 5,000 rpm, cell disruption time of 5 time, and gas rate of 10 L/min). For the first central composite design (CCD) of experiments, it was employed to search for the optimal values of cell concentration (corresponding to 25.52%) and glass beads-volume (corresponding to 1,396.45 ml). In this case, the estimated maximal productivity of ADH was found to be 337.93 (U/ming) based on the second ordered polynomial model. Unfortunately, the optimal values were not observed at the central point of contour map. In order to obtain full contour map, the CCD experiments were further employed to obtain the optimal cell concentration and glass beads-volume. Hence, the use of glass beads-volume was decreased to 1,500 ml and the estimated maximal productivity of ADH was 331.19 (U/ming) which approached to the average experimental value of 329.8 (U/ming). Based on the analysis of productivity of ADH, the optimal operating conditions for disruption of baker’s yeast cells by three-phase cell disruptor were agitation rate of 5,000 rpm, cell concentration of 25% (w/v), glass beads-volume of 1,500 ml, and gas rate of 10 L/min.