Trimethylamine removal by plant capsule of Sansevieria kirkii in combination with Bacillus cereus EN1.

Trimethylamine (TMA) contamination produces a strong "fishy" odor and can cause pathological changes in humans. By screening native microorganisms from Sansevieria kirkii exposed to 100 ppm TMA, it was shown that endophytic bacteria number 1 (EN1) and number 2 (EN2) have a higher TMA tolerance and removal capacity than other bacteria species in a closed system. In addition, EN1 and EN2 demonstrated the ability to produce high quantities of indole-3-acetic acid (IAA) and use 1-aminocyclopropane-1-carboxylic acid (ACC), which is found normally in plant growth-promoting bacteria (PGPB). Moreover, 16S ribosomal DNA (rDNA) sequences of EN1 and EN2 identification showed that EN1 and EN2 was the same bacteria species, Bacillus cereus. B. cereus EN1 was chosen to apply with S. kirkii to remove TMA in a plant capsule, which was compared to control conditions. It was found that 500 g of soil with S. kirkii inoculated with B. cereus EN1 had a higher TMA removal efficiency than other conditions. Moreover, the flow rate of TMA-contaminated gas was varied (0.03-1 L min-1) to calculate the loading rate and elimination capacity. The maximum loading rate of 500 g soil with B. cereus EN1-inoculated S. kirkii was 2500 mg m-3 h-1, while other conditions showed only around 250-750 mg m-3 h-1. Therefore, a plant capsule with B. cereus EN1-inoculated S. kirkii had the potential to be applied in TMA-contaminated air.