Evening star., 1951-10-15
Crop Which Doubles
Itself Every "a Hours
ne-CeIIed Plant ChIoreIIu
Moy Be Source of Food
By Thomos R. Henry


A new kind Of agriculture with q crop
which doubles itself every "a hours il
being pioneered by the Carnegie Institu-
ton Of Washington.
This Is the factory y-style culture Of
what is probably the 1owliest Of living
things and perhaps the most ancient
now extant-the green alga chlorella.
It is one-celled plant. It is found
IN fresh water over most of the world,
but it Is SO minute that, unless present
In enormous concentration, it usually
Is invisible. Sometimes 1t gives the sur
face waters Of ponds greenish tinge.
A chlorella usually is spherical in form
and has an average diameter Of about
20-millionths of an inch.
But, chemical tests have shown, it is
fairly rich in some Of the essential
vitamins and also in the amino acids
from which proteins. the building stones
Of the animal body, are made. During
the war extensive experiments were car
ried on In the hopes of extracting from
1t germ-killing substance similar to
penicillin. Thus knowledge of its growth
habits which form part of the basis
for the present experiment was obtained.
Believe It Useful Food.
There Is every reason to believe that
it will form a good food-if not for
man at least for some of the animals
upon which man feeds Chicken feeding
experiments now are under way at the
University Of Maryland. Until the ac-
tual effects are determined, Carnegie
scientists say, there can be no definite
pronouncement on food values.
The great attractiveneSs Of chlorella
is due to its enormous reproduction rate
under favorable circumstances. Actual
ly, billions of individual chlorella are
contained in a small glass bottle, but
billions mean little when applied to this
organism. The culture process seems
more like manufacturing than farming.
It takes on new Importance with the
possibly epochal discovery just an
nounced by the United States Public
Health Service of means Of making the
energy Of sunlight 100 per cent efficient
in building up carbohydrates. Chlorella
was the organism used in these expert
mentS.
The Carnegie Institution, President
Vannevar Bush announced today, has
arranged for project to be carried out
by the Arthur D. Little Co. Of Cam
bridge, Mass, for development of
During the past six months pilot plant
with a total growing area of $4,000
square feet has been constructed and
put in operation. In one unit Of this
pilot plant suspension Of the one
celled organisms is exposed to sunlight
by being pumped continuously through
a large, transparent, plastic tubular
channel. In a second unit the suspen-
sion is circulated in trough with
transparent plastic cover.
Material Harvested Daily.
Continuous growth has been main
tanned and material harvested daily.
During the next phase of the project
emphasis will be placed on obtaining
estimates Of the cost of full-scale in
stallation and on finding out whether the
product is satisfactory for various pur-
poses.
This pilot plant" says Carnegie
statement, "has for its purpose finding
out whether large-scale algal culture is
feasible technically and economically as
a means of utilizing solar energy. # it
is. algae might represent an increase in
the worlds food supply or source Of
industrial raw materials"
Meanwhile, plant biologists at the
Carnegie's Palo Alto (Calif) laboratory
and DR.. J. E. Myers of the University
of Texas are making further study Of
the environmental factors that in
fluence algal growth, which might cause
notifications of the present pilot plant
setup.
The major problems, Carnegie scien-
fists explain, is to keep the algae con-
stantly moving while exposed to sun
light or artificial light. Otherwise the
organisms increase so rapidly that that
many of them are shaded from light.
The constant harvesting also is neces-
Sary.
Handled in Centrifuge.
Harvesting itself is accomplished by
treating the algae-flled water in a
centrifuge, an apparatus on much the
same principle as cream separator.
No filter can be made fine enough to
trap the ultraminute organisms. An
effort is made to keep the culture at
a constant level. In the wartime expert
ments the algae were grown in TASKS
which remained stationary. This process
proved inadequate.
The Carnegie scientists are making
no predictions about this pioneering
effort toward new type Of agriculture
and they frankly expect lot Of bugs"
to develop before there is clear road
to success. AS yet they really do not
know what is in chlorella and valuable
substances new to science may be OBJ
tanned. In view of recent developments,
however, the pilot plants promise to be
of great significance for the light they
throw on the utilization of sunshine,
which now promises to replace atomic
energy in the interest of scientists.