Among the flavonoïds, luteolin is a flavone that has been identified in many plants. It is known for its apoptotic potential with damage to DNA and cell cycle blockage. Many studies have shown that luteolin has anti-oxidant, anti-inflammatory, and anti-cancer activities. However, it is known that heat treatment (boiling, cooking, and treating with microwaves …) can influence the structure of flavonoïds, which often leads to changes in their activities. The present study was conducted to study the effect of heated luteolin on anti-tumor activity of glioblastoma cells U87. Glioblastoma cell viability was evaluated by MTT assay. Adhesion assay was performed on different protein matrices (collagen type 1, vitronectin, fibronectin, and poly-L-lysine); migration assay was determined by modified Boyden chambers and videomicroscopy, and finally, angiogenesis was tested in vitro by capillary network formation on Matrigel™. The results obtained show that the thermal treatment significantly reduces its cytotoxic activity and ability to inhibit cell adhesion to different protein matrices. It was also found that the heat processed significantly reduced the ability of luteolin to inhibit cell migration, cell invasion, and endothelial cell angiogenesis (HMEC-1). This suggests that heat treated luteolin has a lower anti-tumor potential than native luteolin. Graphical abstract ᅟ

The present study describes the monitoring of some of the major classes of surfactants in water. The separation, identification, and the quantitative estimation of the compounds were achieved using LC-Q-ToF-MS. The analyses revealed the presence of variety of surfactants including linear alkylbenzene sulfonate (LAS), alcohol ethoxysulfates (AES), and alcohol ethoxylates (AE). Further, emphasis was given to AES as they are one of the most produced and consumed surfactants in the world. And as far as India is concerned, the present study is one of the most significant attempt regarding the identification and quantification of AES. The data obtained during the analysis revealed that the average concentration of AES C12Ex varied from 0.7 to 13.6 μg L⁻¹ while that of C14Ex ranged between 1.3 and 10.4 μg L⁻¹. The risk assessment revealed that higher chain AES are capable of posing medium level risk to the aquatic compartment. In addition, the study also included the physicochemical analysis of water from the selected area. Water was found to be acidic in nature and the salinity, TDS, and EC values were found to be high during the pre-monsoon season. The order of the levels of anionic constituents was of Cl⁻>SO₄²⁻SO₄²⁻>F⁻>NO₃²⁻ ≅ PO₄²⁻ while that of cations were Na⁺ > Mg²⁺ > K⁺ > Ca²⁺. Results of correlation analysis showed that statistically negative correlation exists between AES homologs and pH while slight positive correlations were found between AES and other parameters including TDS and EC. The suitability of this water for domestic and agricultural purposes has been examined on the ground of basic quality indices such as the water quality index (WQI) and sodium adsorption ratio (SAR). The WQI measurements also revealed that the water quality of the region falls under the “very poor” category especially during the pre-monsoon season. The study could explore the cumulative share of these canals in the quality impairment of the receiving Vembanad Lake.

An intensive sampling campaign of airborne fine particles (PM₂.₅) was conducted at Sanya, a coastal city in Southern China, from January to February 2012. Chemical analyses and mass reconstruction were used identify potential pollution sources and investigate atmospheric reaction mechanisms. A thermodynamic model indicated that low ammonia and high relative humidity caused the aerosols be acidic and that drove heterogeneous reactions which led to the formation of secondary inorganic aerosol. Relationships among neutralization ratios, free acidity, and air-mass trajectories suggest that the atmosphere at Sanya was impacted by both local and regional emissions. Three major transport pathways were identified, and flow from the northeast (from South China) typically brought the most polluted air to Sanya. A case study confirmed strong impact from South China (e.g., Pearl River Delta region) (contributed 76.8% to EC, and then this result can be extended to primary pollutants) when the northeast winds were dominant. The Weather Research Forecasting Black carbon model and trace organic markers were used to apportion local pollution versus regional contributions. Results of the study offer new insights into the atmospheric conditions and air pollution at this coastal city.

Electrooxidation is used to study the inhibition behavior of Microcystis aeruginosa, a dominant algae species during water blooms mainly caused by non-point source pollution. The inhibitory effect of current density, A/V ratio, initial algae concentration, and algae growth phase on the growth of algae by electrochemical oxidation was investigated, respectively. Further, the effect of electrolysis on the photosynthesis of algae cells and the degradation of Microcystin-LR (MC-LR) in solution were also studied. The results showed that the inhibitory effect increased with the increase of current density and A/V ratio. The damage of cell structure and the leakage of intracellular substances were observed when the current density was 17 mA/cm². The intracellular chlorophyll a decreased significantly during the culture period. Only when the A/V ratio was 9.75 m⁻¹, the algal growth could be completely inhibited. The inhibitory effect of algae was decreased with the increase of initial algal concentration, and the inhibitory effect of algae in the log growth phase was better than that in the stationary phase. The degradation efficiency of total MC-LR was 91.7% at 90 min. Some other substances could be degraded simultaneously along with the degradation of MC-LR in electrochemical oxidation.

Siderophores, as strong chelators specific to iron, have been intensively studied in relation to the facilitation of biological iron acquisition from iron oxides. In this study, the dissolution of hematite in the presence of the siderophore desferrioxamine B (DFOB) and three low-molecular-weight organic acids (LMWOAs, i.e., oxalic, citric, or malic acid) was investigated at three pH conditions (3.0, 5.5, and 9.0). Hematite dissolution was pH-dependent and LMWOA-specific. The adsorption of DFOB on hematite was significantly higher at pH 9.0 than at the other pH values. The adsorption of oxalic acid on hematite, however, showed a descending trend as pH was increased, and adsorption of citric and malic acids was not significantly affected by pH. The Fourier transform infrared (FTIR) results also indicated the occurrence of these ligands’ adsorption. After acidification, dissolved iron was detected only in suspensions of hematite pre-adsorbed with oxalic acid at pH 5.5 and 9.0 or pre-adsorbed with citric acid at pH 5.5, indicating that these LMWOAs promoted the formation of labile iron on the hematite surface. Based on previous research and the results of this study, a hypothetical model is proposed. These results provide insight into the effect of LMWOAs on the dissolution of hematite promoted by DFOB.

Sulfaquinoxaline (SQX) is an antimicrobial of the sulfonamide class, frequently detected at low levels in drinking and surface water as organic micropollutant. The main goal of the present study is the evaluation of SQX reactivity during chlorination and UV irradiations which are two processes mainly used in water treatment plants. The SQX transformation by chlorination and UV lights (254 nm) was investigated in purified water at common conditions used for water disinfection (pH = 7.2, temperature = 25 °C, [chlorine] = 3 mg L⁻¹). The result shows a slow degradation of SQX during photolysis compared with chlorination process. Kinetic studies that fitted a fluence-based first-order kinetic model were used to determine the kinetic constants of SQX degradation; they were equal to 0.7 × 10⁻⁴ and 0.7 × 10⁻² s⁻¹corresponding to the half time lives of 162 and 1.64 min during photolysis and chlorination, respectively. In the second step, seven by-products were generated during a chlorination and photo-transformation of SQX and identified using liquid chromatography with electrospray ionization and tandem mass spectrometry (MS-MS). SO₂ extrusion and direct decomposition were the common degradation pathway during photolysis and chlorination. Hydroxylation and isomerization were observed during photodegradation only while electrophilic substitution was observed during chlorination process.

The intensive use of insecticides such as chlorpyrifos (CPF) and diazinon (DZN) in the agricultural activities worldwide has produced contamination of soils and/or transport to non-target areas including their distribution to surface and groundwaters. Cyclodextrins (CDs) have been proposed as an alternative in remediation technologies based on the separation of contaminants from soils because they could allow a higher bioavailability for their degradation with a low environmental impact. In this work, the degradation pattern of CPF and DZN and the formation and dissipation of the major degradation products 3,5,6-trichloro-2-pyridinol (TCP) and 2-isopropyl-6-methyl-4-pyrimidinol (IMPH) was established in four agricultural volcanic and non-volcanic soils belonging to Andisol, Ultisol, and Mollisol orders. Both pesticides were highly adsorbed in these soils, consequently, with a greater probability of contaminating them. In contrast, the adsorption of their two main metabolites was low or null; therefore, they are potential groundwater contaminants. The degradation processes were studied in the natural and amended soils with β-cyclodextrin (β-CD) and methyl-β-cyclodextrin (Mβ-CD) for CPF and DZN, respectively. A slow degradation of CPF and DZN was obtained for volcanic soils with observable residues until the end of the incubation time (150–180 days). In Mollisols, the higher degradation rate of CPF was favored by the neutral to basic pH, and for DZN it was related to the lower adsorption and higher bioavailability. The amendment of soils with CDs produced slower degradation rates which led to a greater concentration of the compounds at the end of the incubation time. This effect was more pronounced for DZN. The exception was the Andisol, with no significant changes for both compounds regarding the unamended soil. No residues of TCP were observed for this soil in both conditions during the whole incubation time; nevertheless, the accumulation of TCP was significant in the Ultisol and Mollisols, but the concentrations were lower for the amended soils. The accumulation of IMPH was important in Mollisol amended soils; however, their residues were observed in the volcanic soils during the whole incubation period in the natural and amended soils. An important enhancement of the microbial activity occurred in the system β-CD/CPF in Mollisols, without a more effective degradation of the insecticide. The opposite effect was observed in the system Mβ-CD/DZN mainly in the oxidative activity in all soils. The higher degradation of DZN and IMPH in natural Mollisols was related to the higher hydrolytic and oxidative activities. The stability of the inclusion complexes formed could play an important role for explaining the results obtained with the amendments.

Agricultural soil was treated with biochar (5% w/w) produced from two pyrolysis temperatures (400 and 700 °C) of giant Miscanthus (GMC-400 and GMC-700, respectively), and the subsequent sorption of sulfathiazole (STZ) was evaluated as a function of pH (2, 5, and 7) and aging period (0, 3, and 6 months). Because sorption was nonlinear, with 0.51 < N < 0.75, the linearized sorption coefficient (K d*) was used for the comparison across samples. The K d* of GMC-400 treatment (3.96–9.96 L kg⁻¹) was higher than that of GMC-700 treatment (1.27–3.38 L kg⁻¹). In laps of aging period over 6 months, the sorption of GMC-400-treated soil had gradually increased to be 3.3 times higher than that of untreated soil, whereas there was no statistical difference for GMC-700 treatment. Results of FTIR and SEM analyses revealed that the number of O-containing functional groups in the GMC-400 treatment increases and the micropores of GMC-700 are deformed over time. Sorption was also pH-dependent in the order of pH 2 > pH 5 > pH 7. The sorption hysteresis (H) index for the GMC-400 treatment was higher at pH 7 (3.99) than at pH 5(2.53), and both values had increased after 6 months (4.18 and 3.17, respectively). The results of this study clearly demonstrate that the sorption of STZ on GMC-treated soils is greatly enhanced, mainly through the greater micropore surfaces, the abundance of hydrophilic functional groups over time, and π⁺-π electron donor-acceptor interaction at low pH.

Pollution of environment due to increased exploitation of minerals has been on the rise, and vanadium, a metal in the first transition series essential for mammalian existence, is a major component of air pollution. This study investigated the clinico-pathological, hepato-renal toxicity, and cytogenotoxicity of intraperitoneal exposure of African giant rats (AGRs), a proposed model for ecotoxicological research to sodium metavanadate. A total of 27 adult male African giant rats weighing 975 ± 54.10 g were distributed into two major groups: sodium metavanadate (SMV) treated and control. They were observed daily for clinical signs of toxicity. Four rats from each group were randomly collected and sacrificed after 3, 7, and 14 days of SMV treatment. Liver, kidney, and bone marrow were analyzed for histopathology and micronucleated normochromated and polychromated erythrocytes (MNNCE and MNPCE), respectively. Clinical signs in treated AGR include sluggish and weak movements, un-groomed fur, and labored breathing. Histology of the kidney revealed severe glomerular atrophy, tubular ectasia, and vacuolar degeneration of tubular epithelium, while liver histology showed sinusoidal congestion and severe hepatocellular necrosis after 14 days SMV exposure. Also, MNNCE and MNPCE significantly increased with a decrease in PCE/NCE ratio in SMV-treated AGR, suggestive of alternations in bone marrow cell proliferation. Hence, SMV treatment to AGR resulted to severe clinicopathologic alterations, kidney, and liver dysfunction and cytogenotoxicity evident by somatic mutation induction which could be severe with prolonged exposure. This suggests African giant rat as an ecotoxicological model to measure major health risks to animals and human populations in highly polluted environment.

Chemical stability of As(V) in amended mine-impacted soils was assessed according to functions of incubation period (0, 1, 2, 4, and 6 months), amendment dose (2.5 and 5%), and application timing (0 and 3rd month). Six soils contaminated with 26–209 mg kg⁻¹ of As(V) were collected from two abandoned mine sites and were treated with two alkaline iron-rich materials (mine discharge sludge (MS) and steel-making slag (SS)). Seventeen to 23% of As(V) in soils was labile. After each designated time, As(V) stability was assessed by the labile fractions determined with sequential extraction procedures (F1–F5). Over 6 months, a reduction (26.9–70.4%) of the two labile fractions (F1 and F2) and a quantitative increase (7.4–29.9%) of As(V) in F3 were observed (r ² = 0.956). Two recalcitrant fractions (F4 and F5) remained unchanged. Temporal change of As(V) stability in a sample was well described by the two-domain model (k fₐₛₜ, k ₛₗₒw, and Ffₐₛₜ). The stabilization (%) correlated well with the fast-stabilizing domain (Ffₐₛₜ), clay content (%), and Fe oxide content (mg kg⁻¹), but correlated poorly with kinetic rate constants (k fₐₛₜ and k ₛₗₒw). Until the 3rd month, the 2.5%-MS amended sample resulted in lower As(V) stabilization (25–40%) compared to the 5% sample (50–60%). However, the second 2.5% MS addition on the 2.5% sample upon the lapse of the 3rd month led to a substantial reduction (up to 38%) of labile As(V) fraction in the following 4th and 6th months. As a result, an additional 15–25% of As(V) stability was obtained when splitting the amendment dose into 3-month intervals. In conclusion, the As(V) stabilization by Fe-rich amendment is time-dependent and its efficacy can be improved by optimizing the amendment dose and its timing.