Photochemical advanced oxidative process treatment effect on the pesticide residues reduction and quality changes in dried red peppers

Micro and nanobubbles enhanced ozonation technology: A synergistic approach for pesticides removal

Pesticides production, consumption, and disposal around the world are raising concerns day by day for their human and environmental health impacts. Among developing treatment technologies, ozonation has attracted the attention of many researchers in recent years. It is an emerging and promising technology for removing pesticides in the aqueous environment and degrading the residual pesticides from the fruits and vegetables (F&V) surfaces. This systematic review presents an extensive study of the degradation of different types of residual pesticides from F&V using ozonation, micro- and nanobubble (MNB) ozonation, or other advanced techniques such as microwaves/ultrasonication and advanced oxidation process. This review compiles the studies that reported the effect of MNB size on the dissolution of ozone gas in the washing medium and its effect on the degradation of residual pesticides from F&V. The mechanism and routes of pesticide degradation and how integrating MNB technology (MNBT) can help overcome economic losses, reduce health issues for consumers, and save the environment from harmful chemicals used in the pesticides are also discussed. The article encourages the development and utilization of MNBT not only in agriculture, but aquaculture, fisheries, food industries, food storage, and packing, for reducing/degrading the residual pesticides from foods and support environmental sustainability as well as improve international trade.

Removal of Pesticides from Lemon and Vegetables Using Electrolyzed Water Kitchen Devices

The possibility of using kitchen electrolyzed water devices (EWDs) for removing residual concentrations of pesticides (malathion, fenitrothion, and p,p'-DDT) from lemon, cucumber, and carrot surfaces was tested. Three commercial devices with different parameters were tested, and their effectiveness was compared with traditional washing methods using water. Based on the results, it was found that by using EWDs, the best removal of water-soluble pesticides was achieved with malathion and fenitrothion (reduction of up to 80%). The worst effectiveness was observed for lipophilic DDT, where a reduction of 20 to 40% was noted. Traditional methods proved to be more effective for removing DDT. Our studies have shown that EWDs can effectively remove pesticide residues; however, further studies should be conducted on a wider spectrum of pesticides and the process should be optimized.

Investigation of Residue Dissipation of Fluxapyroxad and Its Metabolites in Chinese Cabbage and Spring Scallion Using Different Application Methods

Fluxapyroxad, a persistent fungicide in soil, was investigated for differences in residue dissipation in Chinese cabbage and spring scallion through the application methods of soil, foliar, and systemic treatment. Soil application of 0.4% granule fluxapyroxad resulted in residues up to 0.09 mg kg-1 in the scallion, while it did not contribute to the residues in the harvested cabbage. The 50% dissipation time (DT50) of fluxapyroxad in the scallion was 6.8 days. The residues from systemic treatment were highly correlated with foliar application in both the cabbage and the scallion, and the initial residue and DT50 values were similar for foliar and systemic treatments. In comparing the residues from the systemic treatments between the two crops, the initial residue was 3.11 and 0.22 mg kg-1 in the cabbage and the scallion after the systemic treatment, respectively. The DT50 values were 2.6 and 12.2 days in the cabbage and the scallion, respectively. The theoretical dilution effect due to crop growth was higher for the cabbage (4-fold) than for the scallion (1.2-fold), and the half-lives of fluxapyroxad without considering the dilution effect were 6.4 days in the cabbage and 17.8 days in the scallion. Thus, the residue difference was drastically reduced after 14 days from the last treatment.

Effect of Abiotic Signals on the Accumulation of Saponarin in Barley Leaves in Hydroponics Under Artificial Lights

Functional flavonoid production is a new agenda in the agricultural industry, and young barley leaves (YBL) are one of the highlighted crops due to their health-beneficial flavonoid, saponarin. For the year-round cultivation of a high saponarin content of YBL, abiotic signal effects on the biosynthesis and metabolism in YBL need to be understood clearly. In this research, the effects of reactive oxygen species (ROS)-related abiotic signals, such as light, potassium, and sodium, were investigated on the biosynthetic metabolism in YBL cultivation under artificial lights. A higher quantity of blue-rich white light (6500 K of light temperature) irradiation enhanced ROS levels and the related enzyme activities (APX and CAT), as well as photosynthesis and saponarin amount, while red-rich white light (3000 K of light temperature) increased the photosynthesis only. In addition, 1.0 g L-1 K+ treatment in water slightly reduced ROS levels and increased saponarin accumulation in YBL. These blue-rich light and K+ supplemental conditions relatively increased OGT expression and reduced 4-coumaric acid and isovitexin as saponarin precursors. Furthermore, the relative ratio of lutonarin as an oxidized product of saponarin increased in increments of light quantity. Finally, the abiotic conditions for saponarin production were optimized with the mixture solution treatment of 1.0 g L-1 Na+ and 1.0 g L-1 K+ under 500 PPFD of 6500 K light, and the saponarin amount per leaf was 219.5 μg plant-1; it was comparable amount with that under sunlight condition.

Removal of organic pollutants through hydroxyl radical-based advanced oxidation processes

The use of Advance Oxidation Process (AOPs) has been extensively examined in order to eradicate organic pollutants. This review assesses the efficacy of photolysis, O3 based (O3/UV, O3/H2O2, O3/H2O2/UV, H2O2/UV, Fenton, Fenton-like, hetero-system) and sonochemical and electro-oxidative AOPs in this regard. The main purpose of this review and some suggestions for the advancement of AOPs is to facilitate the elimination of toxic organic pollutants. Initially proposed for the purification of drinking water in 1980, AOPs have since been employed for various wastewater treatments. AOPs technologies are essentially a process intensification through the use of hybrid methods for wastewater treatment, which generate large amounts of hydroxyl (•OH) and sulfate (SO4·-) radicals, the ultimate oxidants for the remediation of organic pollutants. This review covers the use of AOPs and ozone or UV treatment in combination to create a powerful method of wastewater treatment. This novel approach has been demonstrated to be highly effective, with the acceleration of the oxidation process through Fenton reaction and photocatalytic oxidation technologies. It is clear that Advance Oxidation Process are a helpful for the degradation of organic toxic compounds. Additionally, other processes such as •OH and SO4·- radical-based oxidation may also arise during AOPs treatment and contribute to the reduction of target organic pollutants. This review summarizes the current development of AOPs treatment of wastewater organic pollutants.