Spirogyra culture and biomass hydrolysis
The microalga used in this work was Spirogyra sp. (division
Chlorophyta, family Zygnemaceae) acquired from SAG (Sammlung
von Algenkulturen G€ottingen) of the University of G€ottingen
(reference: SAG 170.80). The microalga was grown in an open
raceway pond and the biomass was harvested and dried as previously
described [13]. The biomass was characterized in terms of
moisture, total sugars, crude protein, fat, and ash contents, according
to the A.O.A.C standard methods [18]. The Spirogyra
biomass used in this work had the following average composition
(% (w/w) dry weight basis): 45.1 ± 4.2% total sugars, 22.0 ± 0.3%
crude protein, 3.6 fat ± 0.1%, 25.9 ± 0.3% ash and 3.4% others (by
difference).