Ultrasound assisted extraction of β-carotene from Spirulina platensis

This paper illustrates the Ultrasound Assisted Extraction (UAE) of β-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 β-carotene. From economic point of view, the optimal conditions for the extraction of β-carotene from Spirulina were 1.5 g Spirulina (2 min pre soaked in methanol) in 50 ml n-heptane at 30 °C temperature, 167 W/cm2 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 β-carotene.

► Ultrasound assisted extraction of β-carotene from Spirulina platensis.
► 0.03 g/ml biomass to solvent ratio gave maximum extraction yield.
► Extraction yield does not increase after 61.5% duty cycle.
► 2 min soaking in methanol resulted into 12 times increase in β-carotene extraction.
► Electrical acoustic intensity of 167 W/cm2 showed maximum yield of β-carotene.