The Use of a Gas Chromatography/Milli-whistle Technique for the On-line Monitoring of Ethanol Production Using Microtube Array Membrane Immobilized Yeast Cells

Abstract

Hollow, poly(L-lactic acid) microtube array membranes (MTAM) were used in preparing membranes that contained immobilized yeast cells. To evaluate the performance of the developed system for continuous and fed-batch fermentation, a gas chromatography/milli-whistle device was used to on-line monitor the production of ethanol. The milli-whistle was connected to the outlet of a GC capillary, and when the fermentation gases and the GC carrier gas passed through it, a sound with a fundamental frequency was produced. The online data obtained for frequency-change vs. retention time can be recorded after a fast Fourier transform. In typical bioethanol fermentation, the yeast cells cannot be recycled, whereas the artificial yeast-MTAMs can be. The hollow-MTAM containing immobilized yeast cells significantly enhanced to bioethanol productivity, and represent a novel, promising technology for bioethanol fermentation. Our data indicate that the gas chromatography/milli-whistle device, which is economical and stable, is a very useful detector for long-term monitoring.

Combined Approach for Determining Diuron in Sugarcane and Soil: Ultrasound‐Assisted Extraction, Carbon Nanotube‐Mediated Purification, and Gas Chromatography–Electron Capture Detection

“…This method effectively reduces the time cost, economic cost, and environmental pollution associated with herbicide detection and may be used to detect the residue of thermally unstable herbicides and pesticide in sugar‐based products, sugarcane, and food. In sugar manufacturing processes, this method can be used to monitor changes in herbicide and pesticide residue levels in real time during the evaporation, boiling, and crystallization of sugar to ensure food safety (Wu et al., ; Ye et al., ). Finally, the method efficiently determines thermal decomposition products from the pyrolysis of thermally unstable herbicides.…”