Stereoselective analysis of chiral pesticides: a review.

Chiral organic pollutants, including pesticides, herbicides, medicines, flame retardants, and polycyclic musk, represent a significant threat to both the environment and human health. The presence of asymmetric centers in the structure of chiral pesticides introduces stereoisomers with distinct distributions, fates, biomagnification capacities, and cytotoxicities. In aquatic environments, pesticides, as persistent/pseudo-persistent compounds, have been detected in substantial quantities, posing severe risks to non-target species and, ultimately, public health through water supply and food exposures. In response to this environmental challenge, stereoselective analytical methods have gained prominence for the identification of pesticide/drug enantiomers in recent years. This review examines the environmental impact of chiral pesticides, emphasizing the distinct biological activities and distribution patterns of their stereoisomers. By highlighting the advancements in liquid chromatography for enantiomeric analysis, the review aims to underscore the urgent need for a comprehensive understanding of these pollutants to facilitate informed remediation strategies and ensure the safer dispersal of chiral organic pollutants in the environment, thereby addressing the potential risks they pose to ecosystems and human health. Future research should focus on developing sustainable and efficient methodologies for the precise analysis of stereoisomers in complex matrices, particularly in sewage water, emphasizing the importance of sewage processing plants in ensuring water quality.

Application of Iron Nanoparticles Synthesized from a Bioflocculant Produced by Yeast Strain Pichia kudriavzevii Obtained from Kombucha Tea SCOBY in the Treatment of Wastewater.

Studying the production of Iron (Fe) nanoparticles using natural substances is an intriguing area of research in nanotechnology, as these nanoparticles possess biocompatibility and natural stability, which make them useful for a variety of industrial applications. The study utilized Fe nanoparticles that were synthesized using a bioflocculant and applied to eliminate different kinds of pollutants and dyes found in wastewater and solutions. The study involved the generation of Fe nanoparticles through a bioflocculant obtained from Pichia kudriavzevii, which were evaluated for their flocculation and antimicrobial capabilities. The impact of the Fe nanoparticles on human embryonic kidney (HEK 293) cell lines was studied to assess their potential cytotoxicity effects. An array of spectroscopic and microscopic methods was employed to characterize the biosynthesized Fe nanoparticles, including SEM-EDX, FT-IR, TEM, XRD, UV-vis, and TGA. A highly efficient flocculating activity of 85% was achieved with 0.6 mg/mL dosage of Fe nanoparticles. The biosynthesized Fe nanoparticles demonstrated a noteworthy concentration-dependent cytotoxicity effect on HEK 293 cell lines with the highest concentration used resulting in 34% cell survival. The Fe nanoparticles exhibited strong antimicrobial properties against a variety of evaluated Gram-positive and Gram-negative microorganisms. The efficiency of removing dyes by the nanoparticles was found to be higher than 65% for the tested dyes, with the highest being 93% for safranine. The Fe nanoparticles demonstrated remarkable efficiency in removing various pollutants from wastewater. In comparison to traditional flocculants and the bioflocculant, biosynthesized Fe nanoparticles possess significant potential for eliminating both biological oxygen demand (BOD) and chemical oxygen demand (COD) from wastewater samples treated. Hence, the Fe nanoparticles synthesized in this way have the potential to substitute chemical flocculants in the treatment of wastewater.

Response of Corchorus olitorius Leafy Vegetable to Cadmium in the Soil.

Corchorus olitorius, a leafy vegetable with high nutrient content, is normally collected from the wild, in areas that are prone to cadmium (Cd) toxicity. However, studies on how Cd accumulation affects vegetative and reproductive traits of leafy vegetables in South Africa are limited. Therefore, this study tested the effect of Cd accumulation on C. olitorius morphological traits. Plants were grown under various Cd concentrations and studied for variation in vegetative and reproductive traits as well as accumulation in roots and shoots. Plants exposed to 5 mg/kg Cd had longer roots with higher moisture content, heavier fresh and dried stems, as well as dried leaves, which indicated a hormetic effect in C. olitorius after exposure to low Cd concentration in the soil. Again, plants treated with 5-10 mg/kg Cd, accumulated toxic (>10 mg/kg dry weight) Cd within shoots and roots, with minor morphological alterations. Plants could survive, with some morphological defects, Cd toxicity up to 20 mg/kg in soil. Only plants exposed to 5 mg/kg could reproduce. Cd accumulation increased with an increase in the soil, with higher accumulation in shoots. The translocation factor was high (>1) in all Cd concentrations. In conclusion, C. olitorius can accumulate toxic Cd, and yet grow and reproduce either normally or better than the control. The proposed dose of Cd that induces hormesis in C. olitorius is 5 mg/kg in the soil. Therefore, C. olitorius is suitable for phytoremediation of Cd contaminated soils, but unsafe for consumption when it grows in such areas.