ABSTRACT

Chemical composition and molecular weight of dissolved organic matter were determined by employing chemical analysis and Sephadex Gel filtration method with respect to bacterial degradation products of green algae. The chemical composition is as follows; pigment materials 15%, lipid and organic acid materials 30%, proteinous materials 26% and carbohydrate materials 8%. The molecular weight of the dissolved organic matter is distributed in wide ranges. Organic matter with high molecular weight (> 50, 000) consists mainly of proteinous and carbohydrate materials, intermediate one (1, 500-50, 000) consists of pigment and lipid materials. The composition of lower molecular weight matter is not yet known. The dissolved organic matter produced by bacterial degradation of green algal cells is characterized by yellow colouring, which originates in pigments (in main chlorophyll pigments), and high molecular weight organic substances, which consist almost of proteinous substances with lesser amounts of carbohydrate substances. Although there is a considerable difference between the dissolved organic matter of bacterial degradation products and that in natural water, the former is suggested to be an important source of the latter.