ISSN 10674136, Russian Journal of Ecology, 2015, Vol. 46, No. 5, pp. 481–482. © Pleiades Publishing, Ltd., 2015.
Original Russian Text © Sh.R. Abdullin, V.B. Bagmet, 2015, published in Ekologiya, 2015, No. 5, pp. 392–393.
According to Tuchman et al. (2006), many dia
, at low illumination
can assimilate organic substances such as acetate, lac
tate, ethanol, saturated fatty acids, glycerol, amino
acids, and glucose. Some green algae of the genus
are also able to grow in the dark, utilizing
glucose as the sole source of energy and carbon (Yan
tao et al., 2008).
This study was performed with strains of the diatom
.) W. Sm. and green alga
(Skuja) Kalina et Punc.
from the Propashchaya Yama Cave, the Southern
Urals, with the purpose to test them for the ability to
utilize exogenous sugars (glucose) as a energy source
in the light and in the dark, and to compare the rates
of their growth under different illumination condi
The Propashchaya Yama Cave, one of the largest
karst caves in the Urals (Gareev, 2007), is in the upper
part of the left slope of the Belaya River valley 4.9 km
southwest of the village of Kiekbaevo (Burzyanskii
raion, Republic of Bashkortostan).
strain was isolated from a
cyanobacterial–algal cenosis of lake bottom sedi
ments accumulated in the cave, and the
, from such a cenosis growing on the wall near
the shaft entrance on the cave floor. Before the experi
ment, both strains were purified of fungi and bacteria by
treatment with nystatin (Sirenko et al., 1975). The most
effective concentration of this antibiotic was experi
mentally determined at 20–25
The strains were cul
tured in Gromov’s (1965) mineral medium no. 6,
which in the diatom culture was supplemented with
sodium silicate. The experiment was performed in four
variants: (1) in the light in mineral medium, light con
trol (LC); (2) in the light with 1% glucose (LG); (3) in
the dark in mineral medium, dark control (DC); (4) in
the dark with 1% glucose (DG).
The strains were cultured for 10 days, cell counts
were taken with a standard hemocytometer chamber.
The results were processed statistically using Statistica 8.0
and Microsoft Office Excel 2007 program packages.
The number of cells in the control
culture in the light initially increased at a high rate,
which became slightly lower on day 8. This was proba
bly explained by depletion of mineral substances in the
medium. The differences in the cell number between
this culture and experimental culture in the dark (LC
vs. DG) remained statistically significant throughout
the experimental period (
< 0.014), as was the differ
ence between the two control variants (LC vs. DC;
0.007). In case of experimental culture in the light
(LG), the differences from LC were significant begin
ning from day 3 of the experiment (
= 0.000) (Fig. 1).
Cells in the LG variant divided very slowly, but
their number did not decrease (Fig. 1). The differences
between LG and DG became statistically significant
only on day 8 (
= 0.000). The rate of culture growth
Experimental Analysis for the Possibility of Heterotrophy in Algae:
The Example of Some Strains from the Propashchaya Yama Cave
Sh. R. Abdullin and V. B. Bagmet
Bashkir State University, ul. Zaki Validi 32, Ufa, 450076 Bashkortostan, Russia
Received January 10, 2014
, mode of nutrition, autotrophy, heterotrophy
Days of experiment
Dynamics of cell number in
W. Sm. cultures under different conditions: (
) number of
; LC, light, control; (LG) light, glucose;
(DC) dark, control; (DG) dark, glucose.