Physico-chemical properties of haemolymph of Chilopoda and Diplopoda (Myriapoda, Arthropoda): protein content, pH, osmolarity

Abstract

Different physico-chemical properties of the haemolymph of various chilopod (Lithobius forficatus and Scolopendra cingulata) and diplopod species (Rhapidostreptus virgator, Chicobolus spec.) were investigated. Haemolypmph pH ranged from 7.0 to 8.5 being slightly more alkaline in the millipede species. Protein content and osmolarity was higher in chilopods (between 296 and 371 mOsm and 65 to 73 mg protein/ml haemolymph) than in diplopods (200 to 229 mOsm and 21 to 56 mg/ml). A chromatogram-spectrophotometry of SDS-PAGEs of haemolymph samples showed 42 to 53 protein fractions in R. virgator and 43 in Chicobolusspec. (19 and 16 respectively, represented larger fractions). A haemocyte lysate only showed 12 protein fractions none of which exclusively occurred in the lysate. The results are discussed with regard to earlier investigations which partly differed significantly.