Hypobranchial glands

People have long used marine organisms as the source of a limited number of synthetic products used in everyday life. Perhaps the most famous of these organisms has been the mollusk Murex bran-dans, from which a beautiful purple dye can he extracted. The dye is obtained from a small organ of the mollusk (the hypobranchial gland), and its preparation is so expensive that it was traditionally used as a dye only for clothing worn by the nobility. For that reason, the dye was called royal purple or, more commonly, Tyrian purple, after the region from which it is obtained. 

Sulphate esters of glucans appear to be rather uncommon with the exception of the sulphated (J1,4-glucans of molluscs, which are chiefly found in their hypobranchial glands. These sulphated glucans are very similar to synthetic cellulose sulphate, but possibly some contain a 1,4 and a 1,6 linkages their sulphate ester groups are probably attached to glucosyl residues via C-3. 

V. Erspamer, Active constituents of the posterior salivary glands of octopods and of the hypobranchial gland of the purple snail. Arzneimittelforschung 2 253-258 (1952)... 

The color was, and still is, prepared from several mollusks including Murex brandaris, Murex trunculus and Purpura haemostoma, found on the shores of the Mediterranean and the Atlantic coast as far as the British Isles [31, 32]. The method of extraction and preparation of the colorant was one of the most complex, time-consuming, and labor-intensive activities carried out by the ancients. The reasons are (1) it purportedly takes 10,0(X) shellfish to produce one gram of the pure colorant (see Fig. 4.7) (2) the colorant itself is not actually present in the living animal but its precursor must be excised from the snail s hypobranchial gland (3) the colorant must be produced by a complex chemical process involving enzymatic hydrolysis of the dye precursors and subsequent photochemical oxidation. 

In the order Muricidae these carnivorous snails attack molluscs or sessile crustaceans by boring holes in their shells using softening secretions. Hypobranchial and other glands contain small molecular weight substances with pharmacological activity (e.g., murexine, 5HT, etc.). 

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