Some Chemical Constituents of the Mussel (Mytilus edulis)

TISSUES of the common sea-mussel (Mytilus edulis), macerated in 60 % alcohol, during another investigation gave an extract which, after filtering and further addition of alcohol, deposited clusters of colourless crystals on standing.Experiment showed that this crvstalline substance was much more soluble in water than in alcohol and could always be thrown out by further addition of alcohol to the tissue-extracts.Within a range of 70-80 % alcohol, two distinct crystalline forms were observed together with a certain amount of brownish coloured gummy material.At alcoholic strengths nearer to 70 % the predominant form of the crystals was that of prismatic needles.From higher concentrations of alcohol the crystalline deposit was chiefly in the nature of stout hexagonal plates.Previous work with the mussel had been focussed principally upon the possible causes of poisoning in human beings after eating the mollusc [Furth, 1903] and Brieger [1889] isolated a supposed specifically poisonous body which he called mytilotoxin, the existence of which has been disputed by Thesen [1902].Kelly [1904], from analysis of the sulphur content of muscular tissue of Mytilus, calculated that this should contain 5 % of taurine and that the Bojanus organs should yield 1-95 % of that substance.By extraction of these tissues with boiling water, precipitation of the extract with lead acetate solution, and evaporation of the filtrate (freed from lead by 12S treatment), followed by acidification, taurine was isolated, but the yields in both experi- ments were much lower than was expected.During the course of a comparative study of different kinds of muscle, Jansen [1917] made a chemical examination of the extract of the posterior adductor muscle of Mytilus edulis.Following the procedure of Kutscher [1905] he isolated betaine, taurine (0.08 % on wet flesh) and a new substance of