Author/Editor     Florjanič, Maja; Kristl, Julijana
Title     Proučevanje razkužilnega učinka ozona na planktonske in biofilmske mikroorganizme v prečiščeni vodi v dinamičnem laboratorijskem in industrijskem okolju
Translated title     Investigation of ozon disinfection effect on planctonic and biofilm microorganisms in purified water in dynamic laboratory and industrial environment
Type     članek
Vol. and No.     Letnik 61, št. 6
Publication year     2010
Volume     str. 282-288
ISSN     0014-8229 - Farmacevtski vestnik
Language     slv
Abstract     Z rezultati na laboratorijskem modelu in z deset-letnim spremljanjem podatkov prečiščene vode v industrijskem sistemu, ki jo razkužuje ozon, smo celovito razložili obvladovanje njene mikrobiološke kakovosti. Laboratorijsko preskušanje učinkovitosti ozona na planktonske in biofilmske bakterije Stenotrophomonas malthophilia, kot prevladujoče v naši prečiščeni vodi, je pokazalo, da so biofilmske vsaj 533-krat bolj odporne na razkuževanje z ozonom kot istovrstne planktonske bakterije. Ozon v koncentraciji 70 ppb v petih minutah učinkovito uniči 99,98% planktonskih, medtem ko tudi 450 ppb ozona v 120 minutah ni zmanjšalo število biofilmskih bakterij te vrste. Po ozonaciji nastane sekundarni biofilm ?e hitreje kot je nastal primarni, ker soodmrli mikroorganizmi (MO) hrana za preživele. Kljub neučinkovitosti ozona na biofilmske MO, kaže pregled dolgoletnih rezultatov prečiščene vode iz industrijskega sistema trend stalnega vzdrževanja mikrobiološke kakovosti, ki ustreza zahtevam Ph Eur 7.0. Dobre mikrobiološke rezultate pripisujemo kroženju vode s planktonskimi MO skozi rezervoar s 70 ppb ozona, ki jih učinkovito uniči in majhni vsebnosti skupnega organskega ogljika. Rezultati kažejo, da MO niso razvili rezistence v preiskovanem deset letnem obdobju.The continuous maintaining of acceptable quality of purified water in industrial purified water system that is disinfected by ozone is explained by results of laboratory studies and review of 10 years results of purified water. Laboratory study revealed that biofilm bacteria Stenotrophomonas malthophilia, that constitutes the majority of biofilm in our purified water, is more than 533 times more resistant to the ozone as planctonic bacteria of the same species. Ozone at 70 ppb killed 99.98% of planctonic microorganisms (MO) in 5 minutes, however, even 450 ppb of ozone had almost no impact on biofilm bacteria in 120 minutes. After ozonization, secondary biofilm has formed faster than primary due to the fact that dead MO represent nutrient to survived ones. In spite of inefficient impact of ozone on MO in biofilm, 10 years review has shown maintaining of microbial quality of purified water which is in compliance with Ph. Eur 7.0. Excellent microbial results could be attributed to constant recirculation of water through reservoir with 70 ppb of ozone that efficiently killed planctonic MO, and diminish total organic carbon. Results of this study confirmed that resistance of MO towards ozone was not developed in investigated period.
Keywords     biofilm
ozon
dezinfekcija
planktonski mikroorganizmi
prečiščena voda