Ultrasonic intensification as a tool for enhanced microbial biofuel yields

peer-reviewedUltrasonication has recently received attention as a novel bioprocessing tool for process intensification in many areas of downstream processing. Ultrasonic intensification (periodic ultrasonic treatment during the fermentation process) can result in a more effective homogenization of biomass and faster energy and mass transfer to biomass over short time periods which can result in enhanced microbial growth. Ultrasonic intensification can allow the rapid selective extraction of specific biomass components and can enhance product yields which can be of economic benefit. This review focuses on the role of ultrasonication in the extraction and yield enhancement of compounds from various microbial sources, specifically algal and cyanobacterial biomass with a focus on the production of biofuels. The operating principles associated with the process of ultrasonication and the influence of various operating conditions including ultrasonic frequency, power intensity, ultrasonic duration, reactor designs and kinetics applied for ultrasonic intensification are also described

Sono–Soxhlet: in situ ultrasound-assisted extraction of food products

International audienc

Determination of acoustic fields in acidic suspensions of peanut shell during pretreatment with high-intensity ultrasound

The benefits of high-intensity ultrasound in diverse processes have stimulated many studies based on biomass pretreatment. In order to improve processes involving ultrasound, a calorimetric method has been widely used to measure the real power absorbed by the material as well as the cavitation effects. Peanut shells, a byproduct of peanut processing, were immersed in acidified aqueous solutions and submitted to an ultrasonic field. Acoustic power absorbed, acoustic intensity and power yield were obtained through specific heat determination and experimental data were modeled in different conditions. Specific heat values ranged from 3537.0 to 4190.6 J.kg(-1).K-1, with lower values encountered for more concentrated biomass suspensions. The acoustic power transmitted and acoustic intensity varied linearly with the applied power and quadratically with solids concentration, reaching maximum values at higher applied nominal power and for less concentrated suspensions. A power yield of 82.7% was reached for dilute suspensions at 320 W, while 6.4% efficiency was observed for a concentrated suspension at low input energy (80 W).Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)State Univ Sao Paulo UNESP, Food Engn & Technol Dept, Inst Biosci Humanities & Exact Sci IBILCE, Campus Sao Jose Do Rio Preto, BR-15054000 Sao Paulo, BrazilState Univ Sao Paulo UNESP, Food Engn & Technol Dept, Inst Biosci Humanities & Exact Sci IBILCE, Campus Sao Jose Do Rio Preto, BR-15054000 Sao Paulo, BrazilFAPESP: 2013/09344-4FAPESP: 2013/17497-