Page 73 - Ethel D. Hume - Bešam ili Paster: Izgubljeno poglavlje u istoriji biologije

70 B£ CHAMP OR PASTEUR?
dissolves a portion of it, and himself shows how the moulds
are thus supplied with the earthy and alkaline materials
they need. The amount thus furnished is very small, so
that the harvest of moulds is correspondingly limited. If,
however, certain salts, such as aluminium sulphate,
potassium nitrate or sodium phosphate were added to the
sweetened water large moulds resulted, and the inversion
of the sugar was proportionately rapid.
"The meaning of this," says Bechamp, "is that each of
these salts introduced a specially favourable condition and
perhaps helped in attacking the glass, which thus yielded
a greater quantity of its own substance." 1
But, even still, the mystery offermentation was not quite
clear without an explanation of the actual way in which
the change in the sugar was brought about, that is to say,
cane-sugar transformed into grape-sugar.
Here again, as we have already seen, Bechamp solved
the difficulty by a comparison and likened the influence of
moulds to the effects exercised upon starch by diastase,
which, in solution, possesses the property of causing starch
to break up at a high temperature, transforming it first
into dextrin and then into sugar.
Bechamp proved his comparison to be correct by
rigorous experiments. By crushing the moulds which
appeared in his solutions, he found that the cells that
composed them secreted a soluble ferment and that the
latter was the direct agent in transforming the sugar, and
he made a very clear demonstration of this also in regard
to beer-yeast. For instance, just in the same way, the
stomach does not work directly upon food, but only in-
directly through a secretion called gastric juice, which
contains pepsin, a substance more or less analogous to
diastase, and which is the direct agent of the chemical
changes that take place in the digestive organ. Thus, it is
by a soluble product that beer-yeast and certain other
moulds bring about the chemical change that alters the
type ofsugar. Just as the stomach could not transform food
1
Les MicrozymaSy p. 84.