Evening star., 1950-03-27
Eiqht New 'Antibiotics'
Isolated by Chemists
Germ Killers Extracted
From Potatoes, Bananas
By Thomas R. Henry


Eight new "antibiotics germ killers of
the general class of penicillin-have been
isolated from sweet potatoes. cabbages
and bananas by Agriculture Department
chemists.
The antibiotics show encouraging po-
tency in test tubes. Tests of their toxi-
city now are being conducted before they
can be considered for use in experiment
tai medicine.
material was obtained from the
stems of wilt-resistant variety of sweet
potato which has been split into three
fractions. One proved extremely potent
against two varieties of fungi which
cause wilt in sweet potatoes and toma-
toes. 1t had no effect against bacteria.
second was almost useless against
fungi but was very active against bac-
terra of the type that cause boils and
host of other diseases. It had little effect
against other types Of bacteria. A third
actually stimulated the growth Of fungi
but was potent against several quite un-
related kinds of bacteria.
High Resistance a Factor.
From dried cabbage leaves two chemi-
cally distinct substances were obtained
which appeared quite powerful in stop
ping the growth of fungi. They had no
effect on bacteria.
Best of all was the banana. The
banana skin has been referred to as
natures bacteria-proof wrapper and the
Agriculture Department chemists worked
on the hypothesis that the high resist
ance of this fruit might be due to chemi-
calls in its makeup.
From the skins of green bananas was
obtained a material which appeared to
inhibit the growth OF fungi. From both
skin and pulp of ripe bananas two ex-
tracts have been obtained. One stopped
the growth Of three disease-causins
plant fungi The second, perhaps the
most promising of all, showed consider
able potency against all types Of fungi
and bacteria.
This last now has been obtained IN the
form of crystals.
Extracts of about 100 different plants
have been tested in the last few years.
Sweet potato, cabbage and banana have
been selected for intensive analysis be-
cause they seem to offer the greatest
promise.
A sugar that might be used by dis
betics or women trying to reduce Is being
studied by Agriculture Department
chemists.
This sugar Is xylose, by-product
which develops in small quantities when
cellulose major constituent OF plants, Ii
converted into ordinary sugar. 1t would
sweeten foods. It has the rare property.
however, of being treated as an entirely
foreign substance by the human body.
Regardless of the amounts eaten it is not
used in the building of any tissues.
Xylose Not Fattening.
A major objection to too much sugar
is that it is fattening. Xylose never
would form part of fat molecules. There
presumably would be no problem OF its
utilization, as In the case of diabetes.
The Agriculture Department chemists.
however, are moving with great caution
and thus far their findings have not been
too encouraging. The rare sugar may
act as a rather serious poison. They
have tried 1t out on rats. In large
amounts, where it constitutes IS or more
per cent Of the diet, it produces eye
cataracts. These also result when the
amount is reduced to is per cent in
young rats but, the experiments show.
the cataracts tend to disappear as the
animals grow older. A long series OF
experiments with animals will be neces-
sary, the Agriculture Department re-
port stresses before it will be safe to
prescribe the somewhat poisonous sugar
for human beings.