The main objective of this study is to apply neutral electrolyzed water (NEW) spraying to inactivate bioaerosols. We evaluated the inactivation efficiency of NEW applied to inactivate two airborne bacterial Escherichia coli and Bacillus subtilis aerosols inside an environmental-controlled chamber in the study. Generated with electrolyzing 6.15 M sodium chloride brine, the NEW with free available chlorine (FAC) concentration 50, 100, and 200 ppm was pumped with an air pressure of 70 kg/cm 2 through nozzle into the chamber to inactive E. coli and B. subtilis aerosols precontaminated air (initial counts of 3 Â 10 4 colony-forming units [CFU]/m 3 ). Bacterial aerosols were collected and cultured from chamber before and after NEW spray. The air exchange rate (ACH, hr À1 ) of the chamber was set to simulate fresh air ventilating dilution of indoor environment. First-order concentration decaying coefficients (Ka, min À1 ) of both bacterial aerosols were measured as an index of NEW inactivation efficiency. The result shows that higher FAC concentration of NEW spray caused better inactivation efficiency. The Ka values under ACH 1.0 hr À1 were 0.537 and 0.598 for E. coli of FAC 50 and 100 ppm spraying, respectively. The Ka values of FAC 100 ppm and 200 ppm spraying for B. subtilis were 0.063 and 0.085 under ACH 1.0 hr À1 , respectively. The results indicated that NEW spray is likely to be effective in inactivation of bacterial airborne contamination. Moreover, it is observed in the study that the increase of ventilation rate and the use of a larger orifice-size nozzle may facilitate the inactivation efficiency.Implications: Bacterial aerosols have been implicated in deterioration of air quality and occupational health. Effective, safe, and economic control technology is highly demanded, especially for agricultural and food industries. In the study, NEW mist spraying performed effectively in controlling E. coli and B. subtilis modeling bioaerosols contamination. The NEW revealed its potential as an alternative airborne disinfectant worth being discovered for improving the environmental quality in the future.

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The inactivating efficiency using membrane-less electrolyzed water (MLEW) spraying was evaluated against two airborne strains, Staphylococcus aureus and λ virus aerosols, in an indoor environment-simulated chamber. The air exchanged rate (ACH) of the chamber was controlled at 0.5 and 1.0 h -1 . MLEW with a free available chlorine (FAC) concentrations of 50 and 100 ppm were pumped and sprayed into the chamber to treat microbial pre-contaminated air. Bioaerosols were collected and cultured from air before and after MLEW treatment. ) for Staphylococcus aureus of FAC 50 and 100 ppm spraying. In addition, increasing the air exchange rate also improved the inactivation rate. The inactivation coefficient of FAC 100 ppm spraying for Staphylococcus aureus was 0.412 and 0.403 (min -1 ) under ACH 1.0 and 0.5 h -1 . These results indicated that MLEW spraying is likely to be effective in minimizing microbial airborne contamination, especially for poorly ventilated spaces.

This work applied ozone water spraying to explore the feasibility of inactivating bioaerosol. The inactivating efficiency using ozone water (OW) spraying individually against airborne strains Escherichia coli (E. coli) bioaerosols was evaluated in the testing chamber. The setting air exchanged rate (ACH) in this work were 0.5 and 1.0 h−1. The OW operating concentration of 0.5 and 1.0 ppm were sprayed into the testing chamber for inactivating bioaerosols, respectively. Higher OW spraying concentration showed better inactivating results. The inactivation constant of E.Coli against WO 0.5 and 1.0 ppm spraying under ACH 1.0 h−1 was 0.236 and 0.435 (min−1). Moreover, the bioaerosol removal efficiency would increase with ACH. The inactivation decay coefficient of WO 1.0 ppm spraying against E.Coli was 0.312 and 0.435 (min−1) under ACH 1.0 and 0.5 h−1. The results demonstrated that the WO spraying technology was effective in inactivating bioaerosols.

Three methods were adopted for differentiation of aflatoxins B1 and B2 from territrems A and B. They were as follows. (i) Then-layer chromatography coupled with chemical confirmation. A significant decrease in the Rf value of trifluoroacetic acid-treated aflatoxin B1 developed in chloroform-acetone (85:15, vol/vol) was satisfactory in differentiating this toxin from the other three. (ii) High-pressure liquid chromatography monitored synchronously at two wavelengths, 365 and 335 nm. The ratio derived from this double-wavelengh detection could serve as an indicator of the presence of each toxin. (iii) Velasco's flurotoxin meter method, which is used for the determination of aflatoxins within the range of 0 to 50 ng/ml, was not significantly affected by territrems even when they were present in quantities at the microgram-per-milliliter level.