Spectral and acid-base properties of hemolymph plasma and its fractions in the gastropod pulmonate mollusc Achatina fulica

Abstract

A set of normal biochemical indices of the hemolymph plasma in the gastropod pulmonate mollusc Achatina fulica was described in this study. A comparative analysis of the whole plasma and its subfractions enriched with and depleted of the oxygen-carrying protein hemocyanin was carried out using spectrophotometry and spectrofluorimetry. Individual features of the absorption spectra were analyzed using fourth derivatives. An optimal method to estimate the protein concentration was identified. The buffer capacity, equivalence points and pK values of the dominant buffer groups were calculated to characterize the acid-base properties of hemolymph plasma and its subfractions. A major role in maintaining the hemolymph buffer capacity was shown to belong to the bicarbonate buffering system. The results of this study are compared with the data for Helix pomatia available in literature. In the future, the tested indices will be used to devise ecotoxicological criteria for environmental assessment.