Biochemical composition of Mnemiopsis leidyi in the southern Caspian Sea

The biochemical composition of the invasive ctenophore, Mnemiopsis leidyi from the southern Caspian Sea was analysed in terms of total fractions of protein, lipid, ninhydrin-positive substances (NPS), polysaccharides ( PS) and low molecular-weight carbohydrates (LMC). The sum of organic substances per gram dry weight was 84.2 mg g(-1). Protein was the major organic fraction followed by lipid and NPS. The NPS/protein and LNC/PS ratio were 0.45 and 0.50 respectively. Starvation of M. leidyi for a 5-day period resulted in a 32.7% reduction of total organic content. These data will be important in evaluating the feeding condition of M. leidyi specimens from the field.