Effect of extraction temperature on the diffusion coefficient of polysaccharides from Spirulina and the optimal separation method
Journal article
Authors/Editors
Strategic Research Themes
No matching items found.
Publication Details
Author list: Chaiklahan R., Chirasuwan N., Triratana P., Tia S., Bunnag B.
Publisher: Springer
Publication year: 2014
Journal: Biotechnology and Bioprocess Engineering (1226-8372)
Volume number: 19
Issue number: 2
Start page: 369
End page: 377
Number of pages: 9
ISSN: 1226-8372
eISSN: 1976-3816
Languages: English-Great Britain (EN-GB)
View in Web of Science | View on publisher site | View citing articles in Web of Science
Abstract
The extraction temperature had a significant impact on the concentration of polysaccharides derived from solid-liquid extraction of Spirulina. The polysaccharide concentration was significantly higher when the extraction was performed at 90ฐC than when it was performed at 80, 70, and 50ฐC. This result is related to the diffusion coefficients of the polysaccharides, which increased from 1.07 ื 10-12 at 50ฐC to 3.02 ื 10 -12 m2/sec at 90ฐC. Using the Arrhenius equation, the pre-exponential factor (D0) and the activation energy (Ea) for Spirulina polysaccharide extraction were calculated as 7.958 ื 10-9 m2/sec and 24.0 kJ/mol, respectively. Among the methods used for the separation of Spirulina polysaccharides, cetyltrimethylammonium bromide (CTAB, method I) and organic solvent (ethanol, in methods II and III) provided similar yields of polysaccharides. However, the separation of polysaccharides using an ultrafiltration (UF) process (method III) and ethanol precipitation was superior to separation via CTAB or vacuum rotary evaporation (method II). The use of a membrane with a molecular weight cut-off (MWCO) of 30 kDa and an area of 0.01 m2 at a feed pressure of 103 kPa with a mean permeate flux of 39.3 L/m2/h and a retention rate of 95% was optimal for the UF process. The addition of two volumes (v/v) of ethanol, which gave a total polysaccharide content of approximately 4% dry weight, was found to be most suitable for polysaccharide precipitation. The results of a Sepharose 6B column separation showed that the molecular weights of the polysaccharides in fractions I and II were 212 and 12.6 kDa, respectively. ฉ 2014 The Korean Society for Biotechnology and Bioengineering and Springer-Verlag.
Keywords
diffusion coefficients