Methods: Antimicrobial effect was evaluated by measuring adenosine tri-phosphate (ATP) and adenosine mono-phosphate (AMP). ATP is a chemical substance that acts as an energy source for all living organisms on the planet. AMP is derived from ATP during the processing. The presence of ATP or AMP can be considered proof of the presence of a living organism. ATP+AMP were measured at a pillowcase (cotton 100%), a chair cover (polyester 100%), and a sweater (wool 100%), which are using at home. The tested area were wiped using the swab stick, which combines a reagent and self-contained swab device (LuciPac Pen, Kikkoman Co. Ltd. Tokyo), after which light is emitted as a result of chemical reaction between luciferase-luciferin-PPDK reagent and ATP and/or AMP. The level of luminescence was measured using the measuring instrument (Lumitester PD-20, Kikkoman, Tokyo), and the degree of cleanliness is determined based on the amount of ATP+AMP detected by it.Water-soluble essential oils, tea-tree (Melaleuca alternifolla) dissolved with an emulsifier were used in this study (Biken Co. Ltd. Tokyo).This water-soluble essential oil was diluted to 100 times with sterilized distilled water and used as spray. The liquid containing only emulsifier without essential oil was also diluted 100 times and used as a control (control). Samples were obtained by wiping up the surface of the sprayed sites to be tested as mentioned above using the swab stick at 30 minutes after the liquid with essential oil or without (control) was sprayed. A swab stick was moved up and down 10 times in affixed sized area (4cm×4cm) to wipe up. The site for spraying control liquid was about 5cm apart from that for essential oil. The significance of difference comparison of essential oil, rubbing alcohol, and control was evaluated by applying the one-way ANOVA , followed by Bonferroni correction and were considered statistical at p<0.05.
Results: ATP+AMP in the sweater showed 2183.5 ± 1143.5 RLU (Relative Light Unit, n=10) for control, 1445.1 ± 812.2 RLU for tea-tree (n=10) and 246.3 ± 263.5 RLU (n=10) for alcohol. ATP+AMP for alcohol showed significant decreases rather than control or tea-tree. ATP+AMP in the chair cover showed 144.0 ± 151.0 RLU (n=10) for control, 83.0 ± 39.3 RLU for tea-tree (n=10) and 151.5 ± 49.8 RLU (n=10) for alcohol. ATP+AMP for tea-tree tended to decrease, but not significant. ATP+AMP in the pillowcase showed 507 ± 307.6 RLU (n=9) for control, 530.4 ± 667.5 RLU for tea-tree (n=9) and 708.8 ± 607.4 RLU (n=9) for alcohol, but three were no significant differences.
Conclusion: The spraying the liquid containing essential oil tended to decrease ATP+AMP in chair cover (polyester 100%). Alcohol was the most antimicrobial effect in wool fabric. This result is suggested that the antimicrobial effect might be different depending on the type of cloth.