Breaks induced in the deoxyribonucleic acid of aerosolized Escherichia coli by ozonized cyclohexene

Abstract

The inactivation of aerosolized Escherichia coli by ozone, cyclohexene, and ozonized cyclohexene was studied. The parameters for damage were loss of reproduction and introduction of breaks in the deoxyribonucleic acid (DNA). Aerosolization of E. coli in clean air at 80% relative humidity or in air containing either ozone or cyclohexene hardly affected survival; however, some breaks per DNA molecule were induced, as shown by sucrose gradient sedimentation of the DNA. Aerosolization of E. coli in air containing ozonized cyclohexene at 80% relative humidity decreased the survival by a factor of 103 or more after 1 h of exposure and induced many breaks in the DNA.

The effect of ozone and open air factor on surface-attached and biofilm environmental Listeria monocytogenes

“…OAF was first reported when experiments indicated that bacterial survival in aerosolized particles was much greater in a closed vessel than in the open air at the same temperature and humidity (May and Druett 1968). It has been suggested that OAF might be formed from ozone-alkene complexes, similar to those found in external environments, such as photochemical smog (De Mik and De Groot 1978), or naturally occurring volatile plant compounds, such as terpenoids. OAF can be produced using caroterpenoid (noncyclic) or noncaroterpenoid (cyclic) terpenoids (Breitmaier 2006).…”

“…'Open Air Factor (OAF)' was discovered in 1968 and refers to a phenomenon observed when ozone reacts with any compound containing unsaturated hydrocarbons (May and Druett 1968). OAF is not a single molecule, but a collection of highly reactive chemical species (De Mik and De Groot 1978). OAF was first reported when experiments indicated that bacterial survival in aerosolized particles was much greater in a closed vessel than in the open air at the same temperature and humidity (May and Druett 1968).…”

Some factors affecting the airborne survival of bacteria outdoors

“…Studies of survival of Escherichia coli strain MRE 162 were conducted concurrently with those of the test pseudomonad. This strain has been used in many airborne survival studies as it is fairly aerosol-stable indoors but sensitive to OAF de Mik and de Groot 1973, 1977, 1978Cox 1987).…”

An alternative microthread for the study of airborne survival of bacteria outdoors

“…This has been described as the Open Air Factor, or OAF. Further studies by these workers and by Harper (1973) and de Mik and de Groot (1973, 1977, 1978 showed that OAF was formed by the reaction of ozone with olephins produced from unburnt petroleum fumes. This product rapidly decays and is absorbed on to surfaces, so it is effectively destroyed on enclosure unless rapidly ventilated with outdoor air (Hood 1973).…”

“…Preparation of spray suspensions. Pseudomonas maltophifa strain K', a soil isolate, was provided by D r R. Camp- de Mik and de Groot 1973, 1977, 1978Cox 1987). Bacteria were maintained and grown as described by Handley and Webster (1993).…”