Medical and Biological Sciences XXVI/2 - Collegium Medicum ...

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Bożenna Mazalska et. al.
INTRODUCTION
Fungi and straminipilous organisms exhibit a
specific activity, colonizing cellulose, lignin, chitin and
keratin, i.e. the organic material of complex
polymerized structure difficult to access by other
microorganism [1]. These important destruents use the
organic matter for the growth and spread of species,
considerably contributing to self-purification of water
reservoirs. During decomposition of dead plants and
animals, gradual mineralization occurs with release of
elements that pass into the circulation. Partly
decomposed biomass is included in the trophic chain
consisting of subsequent consumers [2,3].
The study objective was to establish species
diversity of fungi and straminipila in water samples
collected from a few bathing sites in the vicinity of
Białystok, to identify or exclude potential etiologic
factors for mycotic infections affecting humans and
animals, and to determine the effect of
physicochemical parameters of the waters examined on
the growth of this group of destruents.
MATERIAL AND METHODS
Description of study area
Mycological investigations were conducted in
2006-2007 in two seasons - spring and autumn and
involved four bathing sites:
- bathing site in Dojlidy localized near Białystok:
area 34.2 ha, max. depth 2.85 m, its south shore
bordered by coniferous woods and its western part with
the town of Białystok; the samples were collected from
the western end of this pond, which is used by the
inhabitants of the town as a beach;
- bathing site in Korycin situated in the west
Korycin Reservoir, covering an area of 6.8 ha, mean
depth 1.35 m. fed by the river Kumiałka;
- two bathing sites on the river Supraśl in the town
of Supraśl (41 km of its middle course) and in Jurowce
(19 km of the middle course). The river Supraśl, 93.8
km long, covering an area of 1844.4 km 2 is a right
tributary of the river Narew and its surface intake is a
source of drinking water supply for inhabitants of
Białystok and its vicinity. The river, due to the unique
landscape assets of the Knyszyńska Forest (boreal
forest resembling southern taiga) is a recreational place
for the region inhabitants and tourists visiting Podlasie
[4].
Mycological investigations
For the analysis of fungi and straminipilous
organisms 3 samples were collected from each
sampling site. The water collected from the respective
reservoir was poured in sterile conditions into beakers,
0.6 l capacity, and placed in the laboratory in
conditions resembling those of the natural
environment. Baiting method described by Fuller and
Jaworski [5], Kiziewicz and Czeczuga [6] was used to
isolate the fungi from the water. The following baits
were used: amphipod crustacean Gammarus pulex,
snake skin Natrix natrix, clover seeds of Trifolium
repens, hemp seeds Cannabis sativa and buckwheat
seeds Fagopyrum esculentum, and onion skin Alium
cepa. Prior to being added to water samples all the
substrates were boiled and rinsed with distilled water a
few times. The baits were successively observed under
an optic microscope (100 and 400x magnification)
every 3-5 days, starting from day 3 of the culture.
Next, several microscope preparations were prepared
from each sample. The samples were stored for about a
month to detect fungal physiology associated with
sexual and asexual reproduction.
Fungi were identified, taking into consideration the
following morphological features: the shape and size of
the tallum, the shape of sporangium and spores, the
structure of the oogonium, antheridium and oospora.
Works of many authors were used to determine the
fungi [7-11].
Physicochemical investigation
Water samples were collected at each study site at a
depth of 0.20 m, by means of a Ruttner’s apparatus
(vol. 2.0 dm 3 ). Physicochemical analyses of
temperature, pH, ammonium nitrogen, nitrite nitrogen
and nitrate nitrogen, phosphates, chlorides and
sulphates were performed. Standard methods as
described by [12, 13] were employed for
physicochemical investigations.
RESULTS
The physicochemical analysis of water used for the
experiments revealed that the highest temperature was
recorded in the water in bath Dojlidy (13.2°C),
whereas the lowest in the bath Korycin (11.5°C)
(Fig. 1).
The highest pH was in the baths Jurowce (7.90),
whereas the lowest in the baths Korycin (6.67) (Fig.2).