Do indoor bacteria represent the indoor microbial characteristic as a ‘biofingerprint’?

摘要

Bacteria in built environments reflects indoor characteristics. Different sources such as human occupancy, activity, gender, age, or ventilation influence the types and concentration of indoor microorganisms. Although detected bacteria and their concentration differ depending on the indoor conditions, the current findings do not show the comprehensive knowledge of the relation between indoor environment and the presence of bacteria. Factorial design approach was used to identify bacteria as ‘biofingerprint’ that reflects indoor environment. From an extensive literature, we have found that indoor bacteria detected are influenced by the sampling location (residence/non-residence), sampling region (air/surface), gender (female/male), and age (children/adult). For example, Corynebacteriaceae and Lactobacillaceae show gender signature, male and female, respectively. The presence of Streptococcaceae presents the possibility that the space is mostly occupied with children, whereas Pseudomonadaceae represents adult signature. Higher concentration of Staphylococcaceae and Propionibacteriaeceae represents the higher human activity. The significant bacterial species are Corynebacteriaceae, Lactobacillaceae, Propioinibacteriaece, Bacillaceae, Staphylococcaceae, Methylobacteriaceae, Micrococcaceae, Moraxellaceae, Enterobacteriaceae, Streptococcaceae, Rhodobacteriaeceae, and Pseudomonadaceae. School sampling was conducted to identify indoor bacterial communities and assess the findings of the factorial design approach. Suspending microbial species were settled onto the Petri dishes filled with TSA. Surface samples were collected using sterile swabs. Sampling locations were offices in a university building, classrooms, locker rooms and libraries in two high schools and an elementary school. Preliminary results showed that the higher concentration of Staphylococcus sp. was observed in the classrooms with higher activity rate in accordance with the factorial design result. Staphylococcus sp. was not influenced by the gender difference. Bacillus sp. was detected in most of the samples but are not dictated by indoor conditions. Gender difference appeared to influence the presence of Corynebacterium.