Machmudah S., Winardi S., Kanda H., Goto M., 2017, Sub- and Supercritical Fluids Extraction of Phytochemical Compounds from Eucheuma cottonii and Gracilaria sp., Chemical Engineering Transactions, 56, 1291-1296.
Subcritical water and supercritical CO2 extraction of phytochemical compounds from Eucheuma cottonii (E. cottonii) and Gracilaria sp. have been investigated at various temperatures and pressures in a semi-batch extractor. These methods are environmentally friendly extraction method without organic solvents other than water and CO2. Eucheuma cottonii (E. cottonii) and Gracilaria sp. are macroalgae that widely grow in the southern coast of Madura Island, Indonesia. They had been used for food in direct human consumption and feedstocks for the pharmaceutical and cosmetics industries due to rich both in minerals and essential trace elements. In order to increase the value of macroalgae, it is necessary to separate them into its component with extraction method. Subcritical water extraction was carried out at temperatures of 120 – 200 °C and pressures of 1 – 10 MPa, while supercritical CO2 extraction was conducted at temperatures of 40 – 80 °C and pressures of 15 – 25 MPa with ethanol as co-solvent. The phytochemical compounds extracted by subcritical water consisted of carrageenan and phenolic compounds. Results of FT– IR spectra analysis showed that the macroalgae components were reacted and consumed in these range temperatures. The change of temperature extraction had a strong influence on the yields of extracted carrageenan and phenolic compounds. By using supercritical CO2, the extract contained ß-carotene and linoleic acid. Recovery of both ß-carotene and linoleic acid increased as increasing temperature and pressure. The addition of ethanol as co-solvent in the supercritical extraction could increase the recovery of ß-carotene and linoleic acid ten and two fold. The results confirmed that subcritical water and supercritical CO2 extraction are applicable method for the separation of phenolic compounds from E. cottonii and Gracilaria sp., and may lead to an advanced plant biomass components extraction technology.
