Search academic texts

Information × Registration Number 0224U002138, 0123U103646 , R & D reports Title Drinking water survey for detection of microscopic algae popup.stage_title Head Semeniuk Nataliia Ye., Доктор біологічних наук Registration Date 06-02-2024 Organization Institute of Hydrobiology of the National Academy of Sciences of Ukraine popup.description2  Microscopic survey of drinking water has shown that green residue in the bottles is caused by algae. 23 species of algae from 6 phyla have been found in the samples of spring and bottled water. The natural spring water contained 13 species dominated by diatoms. Two samples of bottled water, namely, the sample manufactured with the old equipment and exposed under daylight and summer temperature conditions for 6 months and in the sample after only mechanical purification, contained mold fungi from Alternaria genus. In the spring water the algal cell count made up 16214 thousand cells/dm3, and the biomass – 0.243 mg/dm3. The cell count was mainly formed by green algae, and the biomass – by diatoms and green algae. In water samples processed at the “Astreya” plant, the algal cell count and biomass varied within a wide range: 3841–39710 thousand cells/dm3 and 0.015–0.171 mg/dm3. The highest cell count and biomass of algae (39710 thousand cells/dm3 and 0.171 mg/dm3 were recorded in the sample of bottled water whose shelf life had expired (1 year of exposure to daylight and summer temperature). Rather high cell count and biomass of algae were recorded in the water sample, which had undergone filtration, but had not been treated with UV lamp. The algal cell count in that sample was even higher than in the spring. Therefore, green algae dominating that sample could have gotten into the tubes or pouring equipment at the stage of spores. After applying the new UV lamp the algal cell count decreases in 1.6 times, biomass – in 1.7 times, chemical oxygen demand – in 1.7 times, and no mold fungi were detected. Thus, the new UV lamp reduces the number of algal cells and fungi and the organic matter content. The water samples processed at the “Astreya” plant were dominated by the small-celled green alga Chlorella vulgaris. This species is aerophyllic and its spores can be transferred by air currents. Product Description popup.authors Zhezherya Vladyslav A. Semeniuk Nataliia Ye. popup.nrat_date 2024-02-06 Close