Efficient two-frequency ultrasound extraction of β-carotene from the fungus Blakeslea trispora

Abstract

Carotenoids are known for their lower environmental pollution, lower costs, shorter extraction time compared to regular extraction methods and higher extraction efficiency. Ultrasound has significant advantages in the extraction of a great number of biologically active compounds including carotenoids. Benefits of using ultrasound for extraction of various compounds are numerous and include effective mixing and micro-mixing, more efficient energy transfer, reduced thermal and concentration gradients, reduced temperature. The aim of this work was to investigate the influence of two-frequency ultrasound main parameters such as ultrasonic intensity, sonication time, and temperature. Application of two-frequency ultrasound (simultaneous influence of ultrasound with frequency of 20?46 kHz, intensity of 1.5?2.5 W/cm2 and frequency of 1.0?2.0 MHz, intensity of 2.0?3.0 W/cm2) raises the percentage of ?-carotene extraction from biomass of the fungus Blakeslea trispora from 90?92% up to 98?99% in comparison with one frequency ultrasound. The recommended oil temperature for the extraction process is 35?C, because lower temperature leads to reduction of percentage of ?-carotene extraction, and higher temperature promotes unjustified increase of expenditure of energy.