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In this study, we reviewed smog chamber systems and methodologies used in secondary organic aerosol (SOA) formation studies. Many important chambers across the world have been reviewed, including 18 American, 24 European, and 8 Asian chambers. The characteristics of the chambers (location, reactor size, wall materials, and light sources), measurement systems (popular equipment and working principles), and methodologies (SOA yield calculation and wall-loss correction) are summarized. This review discussed key experimental parameters such as surface-to-volume ratio (S/V), temperature, relative humidity, light intensity, and wall effect that influence the results of the experiment, and how the methodologies have evolved for more accurate simulation of atmospheric processes. In addition, this review identifies the sources of uncertainties in finding SOA yields that are originated from experimental systems and methodologies used in previous studies. The intensity of the installed artificial lights (photolysis rate of NO2 varied from 0.1/min to 0.40/min), SOA density assumption (varied from 1 g/cm3 to 1.45 g/cm3), wall-loss management, and background contaminants were identified as important sources of uncertainty. The methodologies developed in previous studies to minimize those uncertainties are also discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pantoea sp. PL-1 inhibits biofilm in AI-2 QS strains, hindering DPD concentration. • PL-1 degrades DPD more efficiently (15 times) than Acinetobacter sp. DKY-1. • Applying PL-1 in an MBR showed 40% more biofilm reduction than DKY-1. • PL-1 alters microbial communities, potentially suppressing EPS production genes. • Hydrophilic, low molecule of PL-1′s AI-2 QQ substance needs crucial exploration. Prior investigations concerning quorum quenching (QQ), which hinders quorum sensing (QS) in microbial communication, concentrated predominantly on N -acylhomoserine lactones (AHLs), which are communicated merely by gram-negative bacteria. However, to combat biofouling more effectively, particularly biofilm-related issues, it is important to explore the inhibition of autoinducer-2 (AI-2), a universal signal (interspecies communication) employed by both gram-negative and gram-positive bacteria. This study aimed to isolate and identify novel strains capable of more effectively inhibiting AI-2 signaling for use in engineering fields. The results revealed that the newly isolated strain Pantoea sp. PL-1 demonstrated remarkable efficacy in attenuating AI-2 signals, leading to a substantial reduction in the AI-2 precursor (S)-4,5-dihydroxy-2,3-pentandione (DPD) in both its pellet (with a DPD removal efficiency of 90.8 % after 180 min, with a rate constant of k = 0.8 h−1) and supernatant form (66.9 %, k = 0.37 h−1). Interestingly, the findings indicate that strain DKY-1, a strain previously reported to exhibit AI-2 QQ activity, only reduced DPD levels in its supernatant form (extracellular activity), while both the pellet and the supernatant of strain PL-1 demonstrated AI-2 QQ activity, indicating both intracellular and extracellular QQ activity. Adding the PL-1 supernatant to co-cultures of two AI-2 QS strains, E. coli K12 and P. mirabilis , successfully reduced DPD by 40 % and 70 %, respectively, without impeding their growth. Additionally, when assessing the impact of PL-1 to minimize membrane biofouling in a membrane bioreactor, it demonstrated superior performance compared to the DKY-1 strain, with a 40 % improvement. The AI-2 QQ compound of PL-1 has been identified as highly hydrophilic and low-molecular-weight, and its exact properties have not yet been fully elucidated. Therefore, uncovering its identity may be an important goal for future research. [ABSTRACT FROM AUTHOR]