The induction of oxidative stress in plants grown on crude oil-contaminated soils was investigated using a diesel contaminated soils model. Twelve cassava stems were grown in four garden pots containing different amounts of diesel oil as contaminants: 150 ppm, 300 ppm, 600 ppm and control (0 ppm). The growth of the plants was monitored for 12 weeks, after which chlorophyll contents, total proteins, lipid peroxidation and activities of catalase, glutathione, and superoxide dismutase (antioxidant enzymes) were determined from the leaves. Significant decreases (p<0.05) were observed in the antioxidant enzymes (67-86%), total proteins (79%) and total chlorophyll content (67%) in the cassava grown on diesel contaminated soil (600 ppm) compared to the control. Consequently, there were significant increase (p<0.05) in the leaf ratio and malondialdehyde (a marker for lipid peroxidation) 0.1909 ± 04 and 1.77 ± 0.34, when compared to the control 0.1530 ± 08 sq.cm/g and 0.10±0.01 µmol/mg protein respectively. It was thus concluded that stunted growth of plants and their death in diesel or crude oil contaminated soil could be traced to oxidative stress.

The main intent of the current research was to appraise if combined application of hydrogen sulfide (H₂S, 0.2 mM) and silicon (Si 2.0 mM) could improve tolerance of tomato plants to arsenic (As as sodium hydrogen arsenate heptahydrate, 0.2 mM) stress. Plant growth, chlorophylls (Chl), PSII maximum efficiency (Fv/Fm), H₂S concentration and L-cysteine desulfhydrase activity were found to be suppressed, but leaf and root As, leaf proline content, phytochelatins, malondialdehyde (MDA) and H₂O₂ as well as the activity of lipoxygenase (LOX) increased under As stress. H₂S and Si supplied together or alone enhanced the concentrations of key antioxidant biomolecules such as ascorbic acid, and reduced glutathione and the activities of key antioxidant system enzymes including catalase (CAT), superoxide dismutase (SOD), dehydroascorbate reductase (DHAR), glutathione reductase (GR), and glutathione S-transferase (GST). In comparison with individual application of H₂S or Si, the joint supplementation of both had better effect in improving growth and key biochemical processes, and reducing tissue As content, suggesting a putative collaborative role of both molecules in improving tolerance to As-toxicity in tomato plants.

Numerous studies reported that BPA could cause oxidative damage to different tissues in rats/mice. This study aimed to perform a systematic review and meta-analysis of BPA exposure on oxidative damage in rats/mice. A comprehensive literature search was conducted using PubMed, Embase, and Web of Science databases from their inception date until July 18, 2020. 20 eligible articles were included in this study. The results showed that BPA could significantly increase the level of MDA (SMD, 16.88; 95%CI, 12.06–21.71), but there was a significant reduction in the contents of antioxidants, such as GR (−10.46, −13.91 ∼ −7.02), CAT (−8.48, −11.66 ∼ −5.30), GPx (−9.37, −11.95 ∼ −6.80), GST (−7.59, −14.51 ∼ −0.67), GSH (−10.64, −13.96 ~ −7.33), and SOD (−6.48, −8.37 ∼ −4.58) in rats/mice. Our study provided clear evidence that BPA exposure could significantly induce oxidative damage in rats/mice. And we also found that the degree of oxidative damage was related to BPA dose, target tissue, intervention means, and exposure duration of BPA.

Due to the large-scale outbreak of Corona Virus Disease (2019), amounts of disinfecting agents was regularly used in public environments and their potential toxicity towards organisms needed to be appreciated. Thus, one mostly used cationic disinfectant, benzalkonium chlorides (BAC(C12)), was selected to assess its potential toxicity one common cyanobacteria Microcystis aeruginosa (M. aeruginosa) in this study. The aims were to explore the toxic effect and mechanism of BAC (C12) on M. aeruginosa growth within 96 h via morphological, physiological, and the relative and absolute quantification (iTRAQ)-based quantitative proteomics variations. The results found that BAC(C12) significantly inhibited cell density of M. aeruginosa at concentrations from 1 mg/L to 10 mg/L, and the 96-h EC₅₀ value was identified to be 3.61 mg/L. Under EC₅₀ concentration, BAC(C12) depressed the photosynthesis activities of M. aeruginosa exhibited by 36% decline of the maximum quantum yield for primary photochemistry (Fv/Fm) value and denaturation of photosynthetic organelle, caused oxidative stress response displayed by the increase of three indexes including superoxide dismutase (SOD), malondialdehyde (MDA), and the intracellular reactive oxygen species (ROS), and destroyed the integrity of cell membranes demonstrated by TEM images and the increase of ex-cellular substances. Then, the iTRAQ-based proteomic analysis demonstrated that BAC(C12) depressed photosynthesis activities through inhibiting the expressions of photosynthetic protein and photosynthetic electron transport related proteins. The suppression of electron transport also led to the increase of superoxide radicals and then posed oxidative stress on cell. Meantime, the 63.63% ascent of extracellular microcystin production of M. aeruginosa was observed, attributing to the high expression of microcystin synthesis proteins and the damage of cell membrane. In sum, BAC(C12) exposure inhibited the growth of M. aeruginosa mainly by depressing photosynthesis, inducing oxidative stress, and breaking the cell membrane. And, it enhanced the release of microcystin from the cyanobacterial cells via up-regulating the microcystin synthesis proteins and inducing the membrane damage, which could enlarge its toxicity to aquatic species.

This study simulated the effects of diving activities on the physiology, enzymatic, and transcriptional responses of Acropora microphthalma. Touching had less impact on Fv/Fm, but a few zooxanthellae were decreased and minor MDA was elevated. Caspase 3 was activated to remove damaged cells, and SOD was increased to alleviate oxidative damage. Under double or triple diving stress, we observed mass loss of zooxanthellae and Fv/Fm, a significant increase in MDA, and SOD, CAT was activated in response to oxidative stress. Transcriptome analyses showed that corals activated immune signaling pathways, anti-oxidation pathways, lysosomal, phagosomal, and cellular autophagy pathways to manage oxidation stress. Moreover, it up-regulated carbohydrate metabolisms, as well as lipopolysaccharide metabolism, glycosphingolipid biosynthesis, photorespiration, amino acid metabolism, and fatty acid beta-oxidation, but down-regulated fatty acid biosynthesis to answer energy insufficiency. This research supported that even in a short time, improper diving activities could have a serious impact on coral health.