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J Appl Phycol (2014) 26:901907 DOI 10.1007/s10811-013-0090-8
Microwave-assisted extraction of the Carrageenanfrom Hypnea musciformis (Cystocloniaceae, Rhodophyta)
E. Vzquez-Delfn & D. Robledo & Y. Freile-Pelegrn
Received: 25 May 2013 /Revised and accepted: 11 July 2013 /Published online: 23 August 2013 # Springer Science+Business Media Dordrecht 2013
Abstract Hypnea musciformis (Wulfen in Jacqu.) J. V.
Lamour. (Rhodophyta) was investigated for its carrageenan production. Traditionally, the desulfation process for carrageenans has been promoted by an alkaline treatment of up to 3 h by conventional heating during carrageenan extraction. New extraction techniques based on microwave irradiation may accelerate this reaction with the advantages of reduced consumption of solvents, energy, and extraction time, suggesting the feasibility of this method as a Green technology. In this study, aqueous- and alkali-treated carrageenans from H. musciformis collected along Quintana Roo coast of Yucatan Peninsula (Mexico) were extracted by conventional method and by microwave-assisted extraction (MAE). Microwave irradiation in closed vessels was used to carry out the alkaline modification. The influence of temperature (85, 95, and 105 C) and extraction time (10 and 20 min) in MAE was investigated in terms of yield, sulfate, and 3,6-anhydrogalactose contents, and Fourier transformed infrared spectra. Although lower carrageenan yields were obtained during MAE extraction, the appa/iota hybrid carrageenan obtained by this novel method is comparable to that extracted by conventional technique. At the maximum temperature used for MAE (105 C), an increase of 3,6-anhydrogalactose as well as an increase of the appa-proportion was observed indicating that MAE could be an adequate procedure for carrageenan extraction of H. musciformis; however, further extraction parameters should be tested to optimize extraction.
Keywords Hypnea musciformis . Rhodophyta . Alkaline treatment . Carrageenan . Microwave-assisted extraction
Introduction
Carrageenans are economically important polysaccharides because of their use in the industry as thickening and stabilizing agents. They consist of linear chains of alternating 3-linked -
D-galactose (G) and 4-linked -D-galactose (D) units, sometimes the last occurring as 4-linked 3,6-anhydrogalactose (DA) unit. Carrageenans are usually sorted into different types based on the presence or not of DA unit and the sulfation pattern: kappa (-; G4S-DA), iota (-; G4S-DA2S), and lambda (-; G2S-D2S,6S), represented by codes proposed by Knutsen et al. (1995), which represent ideal chemical structures with different industrial applicability associated with gelling or viscous...