Determination of the Functional Groups in Algae Parachlorella Kessleri by Potentiometric Titrations

Abstract

The acidic functional groups of the cell wall of native algae Parachlorella kessleri were evaluated by potentiometric titrations. The Gran´s method was applied to determination of the total, strong, weak and very weak acidities. The total organic acidity obtained for biomass was 3.93 mmol g^-1, the largest content belonged to the strong acidic groups (2.13 mmol g^-1) together with the weak acidic carboxylic groups (1.28 mmol g^-1). Very weak acidities represented by the amine groups (0.52 mmol g^-1) did not exceed 14% and they formed the lowest numerous part of all acidic functional groups.