The situation of chlorpyrifos in Mexico: a case study in environmental samples and aquatic organisms.

Chlorpyrifos (CPF) is one of the most commonly used organophosphate pesticides. Because CPF was described as a toxic compound without safe levels of exposure for children, certain countries in Latin America and the European Union have banned or restricted its use; however, in Mexico it is used very frequently. The aim of this study was to describe the current situation of CPF in Mexico, as well as its use, commercialization, and presence in soil, water, and aquatic organisms in an agricultural region of Mexico. Structured questionnaires were applied to pesticide retailers to determine the sales pattern of CPF (ethyl and methyl); in addition, monthly censuses were conducted with empty pesticide containers to assess the CPF pattern of use. Furthermore, samples of soil (48 samples), water (51 samples), and fish (31 samples) were collected, which were analyzed chromatographically. Descriptive statistics were performed. The results indicate that CPF was one of the most sold (3.82%) and employed OP (14.74%) during 2021. Only one soil sample was found above the CPF limit of quantification (LOQ); in contrast, all water samples had CPF levels above the LOQ (x̄ = 4614.2 ng/L of CPF). In the case of fish samples, 6.45% demonstrated the presence of methyl-CPF. In conclusion, the information obtained in this study indicates the need for constant monitoring in the area, since the presence of CPF in soil, water, and fish constitutes a threat to the health of wildlife and humans. Therefore, CPF should be banned in Mexico to avoid a serious neurocognitive health problem.

Agricultural pesticide residues in water from a karstic aquifer in Yucatan, Mexico, pose a risk to children's health.

Yucatan is a region with a high impact of water contamination since it has a karst type soil favoring contaminants entry into the phreatic level, the only source of freshwater in the area. However, no studies report pesticides in water for human consumption or the risk it represents. The objective of this study was to detect and measure pesticide concentrations in domestic tap water to estimate the risk (carcinogenic and non-carcinogenic) to health. A non-probabilistic sampling was applied of 48 tap water sources, and then pesticide detection with solid-phase extraction gas chromatography coupled to the electron capture and flame photometric detectors allowed the estimation of risk through hazard ratios. The present results suggest that aldrin, heptachlor, and ß-BHC residues in domestic tap water from Ticul, Yucatan, pose a risk to children's health, particularly for potential carcinogenic risks.

Valorization of Fermented Shrimp Waste with Supercritical CO2 Conditions: Extraction of Astaxanthin and Effect of Simulated Gastrointestinal Digestion on Its Antioxidant Capacity.

Lactic acid fermentation increases the bioactive properties of shrimp waste. Astaxanthin is the principal carotenoid present in shrimp waste, which can be found esterified in the liquid fraction (liquor) after its lactic acid fermentation. Supercritical CO2 technology has been proposed as a green alternative to obtain astaxanthin from fermented shrimp waste. This study aimed to optimize astaxanthin extraction by supercritical CO2 technology from fermented liquor of shrimp waste and study bioaccessibility using simulated gastrointestinal digestion (GD) of the optimized extract. A Box-Behnken design with three variables (pressure, temperature, and flow rate) was used to optimize the supercritical CO2 extraction. The optimized CO2 extract was obtained at 300 bar, 60 °C, and 6 mL/min, and the estimated characteristics showed a predictive extraction yield of 11.17%, antioxidant capacity of 1.965 mmol of Trolox equivalent (TE)/g, and astaxanthin concentration of 0.6353 µg/g. The experiment with optimal conditions performed to validate the predicted values showed an extraction yield of 12.62%, an antioxidant capacity of 1.784 mmol TE/g, and an astaxanthin concentration of 0.52 µg/g. The astaxanthin concentration decreased, and the antioxidant capacity of the optimized extract increased during gastrointestinal digestion. In conclusion, our optimized supercritical CO2 process is suitable for obtaining astaxanthin from shrimp by-products after lactic acid fermentation.

A comparison of pesticide residues in soils from two highly technified agricultural valleys in northwestern Mexico.

A pesticide characterization is presented for two highly technified valleys in northwest Mexico: Culiacan Valley (CV) in Sinaloa and Yaqui Valley (YV) in Sonora. Approximately 250,000 kg of active ingredients are used every year, half of which are considered highly hazardous pesticides. Legacy pesticides are still present in the soils of these valleys. The aim of the present study was to identify and quantify a wide variety of pesticides in soils and correlate their concentrations with historical and current use. Agricultural soils from both valleys were sampled and analyzed using accelerated solvent extraction and subsequent quantification by gas chromatography with selective detectors. The most frequently detected pesticides (mean, µg g-1) in CV were organochlorines (0.1967), organophosphates (0.0928), synthetic pyrethroids (0.2565), organonitrogen (0.0552), and miscellaneous pesticides (0.1851). In YV, the most frequently detected pesticides were organochlorines (0.8607), organophosphates (0.0001), synthetic pyrethroids (0.0124), and miscellaneous pesticides (0.0009). The pesticides were more diverse in CV compared to those of YV, which was based on the types of crops produced. Both locations presented highly hazardous pesticides, including concentrations above the action levels established by the Canadian Soil Quality Guide. A follow-up risk assessment is recommended to assess potential effects.

Supercritical CO2 extraction of naringenin from Mexican oregano (Lippia graveolens): its antioxidant capacity under simulated gastrointestinal digestion.

A supercritical CO2 method was optimized to recover naringenin-rich extract from Mexican oregano (Lippia graveolens), a flavanone with high antioxidant and anti-inflammatory activity. The effect of the extraction parameters like pressure, temperature, and co-solvent on naringenin concentration was evaluated. We used response surface methodology to optimize the naringenin extraction from oregano; the chemical composition by UPLC-MS of the optimized extract and the effect of simulated gastrointestinal digestion on its antioxidant capacity and total phenolic content were also evaluated. The optimum conditions were 58.4 °C and 12.46% co-solvent (ethanol), with a pressure of 166 bar, obtaining a naringenin content of 46.59 mg/g extract. Also, supercritical optimized extracts yielded high quantities of cirsimaritin, quercetin, phloridzin, apigenin, and luteolin. The results indicated that the naringenin-rich extract obtained at optimized conditions had higher total phenolic content, antioxidant capacity by TEAC and ORAC, and flavonoid content, compared with the methanolic extract, and the simulated gastrointestinal digestion reduced all these values.

Temporal distribution and ecological risk assessment for pesticides in water from the north-central coastal zone of Sinaloa, Mexico.

Water contamination with pesticides is one of the major pollution problems in northwestern Mexico, and this is due to the extensive use of pesticides in agriculture. In this research, water samples of ten sampling sites (fishing grounds, beaches, and both) were analyzed in the search for 28 pesticides (organochlorines, organophosphates, pyrethroids, carbamates, among other chemical classes), supplemented with a calculation of the resulting potential environmental risk. Pesticides were separated from the matrix by liquid-liquid extraction and quantified by gas chromatography coupled to electron micro-capture (organohalogenated) and pulsed flame photometric detectors (organophosphates). In addition, the ecotoxicological risk of pesticides in algae, invertebrates, and fish was assessed, based on seawater pesticide concentrations using the Risk Quotient (RQ) and Toxic Units (TU) approach. The results showed 18 pesticides identified in the analyzed samples, where cypermethrin and chlorpyrifos were identified with the maximum concentrations of 1.223 and 0.994 µg L-1, respectively. In addition, these two pesticides have been associated with acute toxic effects on algae, invertebrates, and fish. It is important to pay particular attention to the search for long-term alternatives to the use of chlorpyrifos and cypermethrin due to their high detection rates and the risks associated with their toxic properties. However, the adoption of alternative measures to synthetic pesticide control should be a priority, moving towards sustainable practices such as the use of biopesticides, crop rotation and polycultures.

Design, synthesis, in silico, and in vitro evaluation of benzylbenzimidazolone derivatives as potential drugs on α-glucosidase and glucokinase as pharmacological targets.

Benzimidazolones have shown biological activities, including antihyperglycemic and hypoglycemic, by inhibiting or activating of α-glu and GK. The aim of this study is the rational design of compounds using in silico assays to delimitate the selection of structures to synthesize and the in vitro evaluation of benzimidazolone derivatives in blood glucose control. A docking of 23 benzimidazolone derivatives was performed; selecting the compounds with better in silico profiles to synthesize by microwave-irradiation/conventional heat and evaluate in enzymatic in vitro evaluation. Compounds 2k, 2m, 2r, and 2s presented the best in silico profiles, showing good affinity energy (-10.9 to -8.6 kcal mol-1) and binding with catalytic-amino acids. They were synthesized at 70 °C and 24 h using DMF as the solvent and potassium carbonate (yield: 22-38%). The results with α-glu showed moderate inhibition of 2k (14 ± 1.23-29 ± 0.45), 2m (12 ± 2.21-36 ± 0.30), 2r (7 ± 2.21-13 ± 1.34), and 2s (11 ± 0.74-35 ± 2.95) at evaluated concentrations (0.1 to 100 µg mL-1). The GK activation assay showed an enzymatic activity increase; compound 2k increased 1.31 and 2.83 more than normal activity, 2m (2.13-fold), 2s (2.86 and 3.74-fold) at 100 and 200 µg mL-1 respectively. The present study showed that the 2s derivative presents moderate potential as an α-glu inhibitor and a good activator potential of GK, suggesting that this compound is a good candidate for blood glucose control through antihyperglycemic and hypoglycemic mechanisms.

Green Extracts and UPLC-TQS-MS/MS Profiling of Flavonoids from Mexican Oregano (Lippia graveolens) Using Natural Deep Eutectic Solvents/Ultrasound-Assisted and Supercritical Fluids.

Mexican oregano (Lippia graveolens) is an important source of bioactive compounds, such as flavonoids. These have presented different therapeutic properties, including antioxidant and anti-inflammatory; however, their functionality is related to the quantity and type of compounds, and these characteristics depend on the extraction method used. This study aimed to compare different extraction procedures to identify and quantify flavonoids from oregano (Lippia graveolens). Emerging and conventional technologies include maceration with methanol and water, and ultrasound-assisted extraction (UAE) using deep eutectic solvents (DES) such as choline chloride-ethylene glycol, choline chloride-glycerol, and choline chloride-lactic acid. Supercritical fluid extraction using CO2 as a solvent was also studied. Six different extracts were obtained and the total reducing capacity, total flavonoid content, and antioxidant capacity by ABTS•+, DPPH•, FRAP, and ORAC were evaluated. In addition, flavonoids were identified and quantified by UPLC-TQS-MS/MS. Results showed that UAE-DES had the best extraction effect and antioxidant capacity using colorimetric methods. However, maceration-methanol was superior in compound content, and highlighting naringenin and phloridzin were the major compounds. In addition, this extract was microencapsulated by spray drying, which provided a protection feature of their antioxidant potential. Oregano extracts are rich in flavonoids and the microcapsules present promising results for future research.