Ultrasound assisted extraction of β-carotene from Spirulina platensis

This paper illustrates the Ultrasound Assisted Extraction (UAE) of beta-carotene from Spirulina platensis. Various parameters such as extraction time, solvent type, biomass to solvent ratio, temperature, electrical acoustic intensity, length of the probe tip dipped into the solvent, duty cycle and pre treatment effect were explored for the extraction of beta-carotene. From economic point of view, the optimal conditions for the extraction of beta-carotene from Spirulina were 1.5 g Spirulina (2 min pre soaked in methanol) in 50 ml n-heptane at 30 degrees C temperature, 167 W/cm(2) electrical acoustic intensity and 61.5% duty cycle for 8 min with probe tip length of 0.5 cm dipped into the extracting solvent from the surface. The maximum extraction achieved under the above mentioned optimum parameters was 47.10%. The pre-treatment time showed a promising effect on the yield as pre-treating the biomass with methanol for 2 min before ultrasonication showed 12 times increase in extraction yield of beta-carotene. (C) 2012 Elsevier B.V. All rights reserved.