Sugar contents and oligosaccharide mass profiling of selected red seaweeds to assess the possible utilization of biomasses for third-generation biofuel production

Abstract

Abstract In the present study, we report the sugar contents and oligosaccharide mass profiles of Kappaphycus alvarezii (Doty) Doty ex Silva, Solieria robusta (Greville) Kylin, Gracilaria corticata (J. Agardh), and Gracilaria corticata v. cylindrica Borgesen. Sugar contents in the biomasses of the studied seaweeds indicated that they represent potential sources of raw material for biofuel conversion. Fractionation improved the sugar yield by loosening cell wall components. A Fourier-transform infrared spectroscopy (FTIR) analysis of different cell wall fractions revealed differences in their structural components. Fractionation exposed and released some of the functional groups, depending on the harshness of treatments. However, variable carbohydrate moieties were observed in each fraction. A MALDI TOF-TOF MS analysis of cell wall revealed a complex and dynamic network of polymers in cell walls. K. alvarezii produced the greatest number of oligosaccharide units, followed by S. robusta, G. corticata v. cylindrica and G. corticata. The cell wall of seaweeds was similar to the polymers in the cell wall of higher plants, which indicated the potential to utilize seaweed biomasses for biofuel production. To the best of our knowledge, the present study is the first to report the oligosaccharide mass profiling (OLIMPs) of red seaweeds. A further detailed analysis of the sugar composition of the cell wall and a linkage analysis of OLIMPs would provide detailed structural information. Present results confirmed the potential utilization of red seaweed biomass as an alternative for biofuel production and potential of red seaweed species to be developed as new industrial crops under blue revolution program.