title: Enhancement of pigment extraction from B. braunii pretreated using CO2 rapid depressurization.
abstract: Extraction of compounds from microalgae requires cell disruption as a pretreatment to increase extraction yield. Botryococcus braunii is a microalga with a significant content of carotenoids and other antioxidant compounds, such as chlorophylls. Cell disruption of B. braunii using CO2 rapid depressurization was studied as a pretreatment for the extraction of carotenoid and chlorophyll pigments. We studied the effect of temperature (21-49°C) and pressure (6-13MPa) during static compression on pigment recovery with supercritical CO2 at 40°C, 30MPa and solvent flow of 4.7LNPT/min. Within the experimental region, the extraction yield of carotenoids and chlorophylls increased by 2.4- and 2.2-fold respectively. Static compression conditions of high pressure and low temperature increased the extraction of carotenoids and especially chlorophylls. We selected 21°C and 13MPa as the cell disruption condition, which produced 1.91g/kg d.s. of carotenoids and 14.03mg/kg d.s. of chlorophylls. Pretreated microalga gave a 10-fold higher chlorophyll extraction yield compared to the untreated sample. While for carotenoids and tocopherols were 1.25 and 1.14-fold higher, respectively. Additionally, antioxidant activity of pretreated microalga (33.22mmol TE/kg oil) was significantly higher than the value for the untreated samples (29.11mmol TE/kg oil) (p≤0.05). Confocal microscopy images showed morphological differences between micro-colonies with and without disruption treatment, suggesting that partial cell disruption by rapid depressurization improved the extraction of microalga compounds.
authors.affiliation: Department of Chemical Engineering, Center of Food Biotechnology and Bioseparations, BIOREN, Universidad de La Frontera (UFRO), Temuco, Chile; Agriaquaculture Nutritional Genomic Center, CGNA, Technology and Processes Unit, UFRO, Temuco, Chile. Electronic address: edgar.uquiche@ufrontera.cl.
authors.forename: Edgar
authors.initials: E
authors.lastname: Uquiche
authors.affiliation: Department of Chemical Engineering, Center of Food Biotechnology and Bioseparations, BIOREN, Universidad de La Frontera (UFRO), Temuco, Chile.
authors.forename: Ivette
authors.initials: I
authors.lastname: Antilaf
authors.affiliation: Department of Chemical Engineering, Center of Food Biotechnology and Bioseparations, BIOREN, Universidad de La Frontera (UFRO), Temuco, Chile.
authors.forename: Sonia
authors.initials: S
authors.lastname: Millao
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry; D002338:Carotenoids / Q000302:isolation & purification* / Q000378:metabolism; D002734:Chlorophyll / Q000302:isolation & purification* / Q000378:metabolism; D000460:Chlorophyta / Q000737:chemistry* / Q000378:metabolism; D011312:Pressure; D013696:Temperature
chemical_list: D002734:Chlorophyll; D002245:Carbon Dioxide; D002338:Carotenoids
keywords: Botryococcus braunii; Cell disruption; Chlorophylls; Microalgae; Supercritical extraction