Characterization and biostimulation of benzene biodegradation in the potting-mix of indoor plants

Abstract: Over 900 volatile organic compounds (VOCs) have been detected in indoor air, where they cause acute and chronic health problems to building occupants. Potted-plants can significantly reduce VOC levels in indoor air, the root-zone bacteria of the potting mix effecting most of the VOC biodegradation. In this study, a baseline community level physiological profile (CLPP) was established for the potting mix bacteria of the indoor plant species, Spathiphyllum wallisii 'Petite', using Biolog EcoPlates, to provide information on the functional abilities of this community. Changes in the CLPP resulting from benzene exposure were then determined and following the identification of the carbon sources associated with changes in the CLPP, biostimulant solutions were formulated and applied to fresh potted-plant specimens. Biostimulation of benzene removal was observed, with increases in removal rates of about 15%, providing proof-of-concept for the biostimulation of this process. The findings further elucidate the mechanisms of bacterial activity associated with removal of indoor airborne benzene, and could be applied to increase VOC biodegradation rates, augmenting the uses of indoor plants in improving building environmental quality.