TY - JOUR
T1 - Mitigation of benzoic acid-driven autotoxicity in waste nutrient solution using O3 and O3/H2O2 treatments
T2 - Seed germination and root growth of Lactuca sativa L.
AU - Han, Uijeong
AU - Lee, Yong Gu
AU - Byeon, Jihui
AU - Chon, Kangmin
AU - Cho, Si Kyung
N1 - Publisher Copyright:
© 2023 Elsevier Ltd
PY - 2023/8/15
Y1 - 2023/8/15
N2 - Benzoic acid (BA), a secondary metabolite released through root exudates, is considered to be the most common inhibitor that leads to plant autotoxicity, even at low concentrations in closed hydroponic systems. In this study, to mitigate BA-driven autotoxicity, the effects of O3 and O3/H2O2 oxidation treatment (O3 concentration: 1, 2, 4, 8 mg L−1, H2O2 concentration: 4, 8 mg L−1) on waste nutrient solution (WNS) were investigated in terms of BA degradation, the rate of germination inhibition (GI), and the rate of root growth inhibition (RI). In the case of O3 treatment, the BA degradation rate improved up to 14.1% as the O3 concentration increased, while alleviation of GI was insignificant (94.6–100%), confirming that a single O3 treatment was unsuitable for mitigating autotoxicity. On the other hand, O3/H2O2 treatment increased BA degradation by up to 24.8%, thereby significantly reducing GI (up to 7.69%) and RI (up to 0.88%). Both the highest BA mineralization rate and phytotoxicity mitigation was observed at BA125 (4–4) (BA mineralization: 16.7%, GI: 12.82%, RI: 11.69%) and BA125 (1–8) (BA mineralization: 17.7%, GI: 7.69%, RI: 0.88%) at each H2O2 concentration. In addition, the operating costs were evaluated by a chemical and electricity cost analysis at the different treatments. As a result, the operating costs of BA125 (4–4) and BA125 (1–8) were calculated to be 0.40 and 0.42 $ L−1 mg−1 of mineralized BA, respectively. After consideration of the mineralization rate, autotoxicity mitigation, and operating cost, BA125 (1–8) was suggested for the optimal treatment condition and our findings would contribute to the alleviation of BA-driven autotoxicity.
AB - Benzoic acid (BA), a secondary metabolite released through root exudates, is considered to be the most common inhibitor that leads to plant autotoxicity, even at low concentrations in closed hydroponic systems. In this study, to mitigate BA-driven autotoxicity, the effects of O3 and O3/H2O2 oxidation treatment (O3 concentration: 1, 2, 4, 8 mg L−1, H2O2 concentration: 4, 8 mg L−1) on waste nutrient solution (WNS) were investigated in terms of BA degradation, the rate of germination inhibition (GI), and the rate of root growth inhibition (RI). In the case of O3 treatment, the BA degradation rate improved up to 14.1% as the O3 concentration increased, while alleviation of GI was insignificant (94.6–100%), confirming that a single O3 treatment was unsuitable for mitigating autotoxicity. On the other hand, O3/H2O2 treatment increased BA degradation by up to 24.8%, thereby significantly reducing GI (up to 7.69%) and RI (up to 0.88%). Both the highest BA mineralization rate and phytotoxicity mitigation was observed at BA125 (4–4) (BA mineralization: 16.7%, GI: 12.82%, RI: 11.69%) and BA125 (1–8) (BA mineralization: 17.7%, GI: 7.69%, RI: 0.88%) at each H2O2 concentration. In addition, the operating costs were evaluated by a chemical and electricity cost analysis at the different treatments. As a result, the operating costs of BA125 (4–4) and BA125 (1–8) were calculated to be 0.40 and 0.42 $ L−1 mg−1 of mineralized BA, respectively. After consideration of the mineralization rate, autotoxicity mitigation, and operating cost, BA125 (1–8) was suggested for the optimal treatment condition and our findings would contribute to the alleviation of BA-driven autotoxicity.
KW - Autotoxicity
KW - Benzoic acid (BA)
KW - Hydroponic
KW - O treatment
KW - O/HO treatment
KW - Waste nutrient solution (WNS)
UR - http://www.scopus.com/inward/record.url?scp=85160689825&partnerID=8YFLogxK
U2 - 10.1016/j.envpol.2023.121930
DO - 10.1016/j.envpol.2023.121930
M3 - Article
C2 - 37270051
AN - SCOPUS:85160689825
SN - 0269-7491
VL - 331
JO - Environmental Pollution
JF - Environmental Pollution
M1 - 121930
ER -