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—A transformation of certain soluble carbo-hydrates into cellulose, which may be regarded as a proximate synthesis of cellulose, has recently been brought to light. This is set up spontaneously in beet-juice, and results in the formation of a hard white substance, insoluble in boiling dilute potash, soluble in the ammonio-copper reagent, converted by sulphuric acid into dextrin and sugar, and by nitric acid into oxalic acid. On adding some of these cellulose lumps to a solution of pure cane-sugar, a further transformation of the saccharose into the same substance is brought about. At the same time there is simultaneously produced a gummy substance, which is precipitated by {16} alcohol as a white amorphous caoutchouc-like mass, of the same composition as cellulose, but swelling up with water, and otherwise differing in its physical properties from cellulose. This latter substance is also formed by the action of diastaste upon a solution of saccharose.

The process of cellulosic fermentation may be represented by the equation:

n. (C12H22O11)

Saccharose.

=

n. (C6H10O5)

Cellulose.

+

n. (C6H12O6)

Glucose.

A similar transformation takes place under the influence of certain fatty seeds, e.g. those of rape and colza; and it is probable that the formation of cellulose in living plants may take place at the expense of saccharose and under the influence of ferments. In support of this it has been established that in the sugar-cane, the formation of wood—i.e. cellulose—is accompanied pari passu by a decrease in saccharose. More recently, A. Brown (Chem. Soc. Journ., 432, 1886) has investigated the formation of cellulose by the “vinegar plant” growing in solutions of the carbo-hydrates, e.g. dextrose in yeast-water. The cells elaborate an extra-cellular fibrin, which acts as a “cell-collecting medium,” and they possess therefore a two-sided activity, i.e. the property above mentioned, in addition to their strictly fermentative activity. The cellulose film in question was found to contain 50 to 60 per cent. of pure cellulose. It is noteworthy that in a solution of levulose the growth of the “plant” is unattended by fermentative action, 33 per cent. of the substance being, on the other hand, transformed into cellulose.