Abstract
Seillière 1 and Billard 2 and others demonstrated the presence of cellulase in Helix pomatia by estimating the amount of glucose produced after action of the cellulase upon suitable substrates. Boynton and Miller 3 showed saccharification of wood by extracts from the ship-worm, Bankia setacea. Trager 4 found a cellulase from symbiotic intestinal flagellates of termites. He estimated the amount of glucose produced, both qualitatively (by means of Benedict's reagent) and quantitatively, after action of the enzyme upon filter paper which was dissolved and precipitated.
We also made use of the fact that reducing substances (carbohydrates) were produced, as proof for the presence of slug cellulase. Two substrates were employed: (1) A finely divided suspension of cellulose was prepared by dissolving 1 gm. of Whatman's No. 40 filter paper in 100 cc. of Cross and Bevan's ZnCl2-HCl reagent. This solution was filtered by suction through cotton and poured into about 800 cc. of distilled water. The resulting precipitate was suspended in 400 cc. of distilled water and centrifugalized. This washing process was repeated ten times and the precipitate was finally allowed to settle out. (2) The outer coverings of date seeds were removed and discarded. Filings from the inner, pearly-white endosperm were put through a 100-mesh sieve and were either suspended in distilled water or weighed in the dry state for use as a substrate.
The slugs were killed with ether. Fifty animals were used. The gastrointestinal tracts and livers were dissected away from the bodies. Three different preparations were studied for cellulase activity: (1) The contents of the stomachs and anterior portions of the intestines. (2) The gut tracts, including the stomachs and intestines. (3) The livers. The second and third preparations were ground with 40-mesh sea sand and extracted with water or 0.7% NaCl for 72 hours.
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