The effects of combined treatment (PAL-U) of plasma-activated liquid (PAL) including plasma-activated water (PAW) and plasma-activated buffer solution (PABS) and ultrasound (U) for the degradation of chlorothalonil fungicide on tomato fruit was investigated. Distilled water and buffer solution were activated by radiofrequency plasma jet for durations of 1, 3, 5, and 10 min to obtain PAL₁ to PAL₁₀. Fruits were immersed in PAL for 15 min and also in distilled water with sonication for 15 min for individual treatments, and in PAL with sonication for 15 min for combined treatments. The maximum chlorothalonil fungicide residues were reduced by 89.28 and 80.23% for PAW₁₀-U and PABS₁₀-U, respectively. HPLC-MS characterization revealed chlorothalonil degradation pathway and formation of 2,4,5-trichloroisophthalonitrile, 2,4-dichloroisophthalonitrile, 4-chloroisophthalonitrile, isophthalonitrile and phenylacetonitrile as degradation products. Treatments also showed no negative effects on tomato quality. Therefore, PAL and PAL-U treatments could serve as effective methods for degrading pesticides on tomatoes.

The effects of a novel technology utilizing a simultaneous combination of Ultraviolet-C radiation and ultrasound energy postharvest treatment on tomato bioactive compounds during 28 days' storage period was investigated by varying Ultraviolet-C radiation intensities of 639.37 or 897.16 µW/cm2 at a constant ultrasound intensity of 13.87 W/L from a 40 kHz-1 kW transducer. A minimal treatment time of 240 s at Ultraviolet-C dosage of 2.15 kJ/m2 was observed to provoke a considerable increase in bioactive compounds content, proportionated to treatment time. Although treatment led to temperature increase in the system reaching 39.33 °C due to heat generation by ultrasonic cavitation, the extractability and biosynthesis of phytochemicals were enhanced resulting in 90%, 30%, 60%, 20%, and 36% increases in lycopene, total phenols, vitamin C, hydrophilic and lipophilic antioxidant activities respectively. Results present the potential use of the combined non-thermal technologies as post-harvest treatment to improve bioactive compounds and antioxidant activity during storage.

A novel method of thermoultrasound-assisted plasma functionalized buffer (PFB) for decontaminating grass carp was evaluated using the Box-Behnken design (BBD) with processing variables including PFB generating voltage (P_V), ultrasound treatment time (U_T) and temperature (T_P). The predicted models were found to be significant (p < 0.05) and displayed sufficient fitness with experimental data as indicated by non-significant (p > 0.05) lack of fit and high coefficient of determination (R²≥0.97) values. The optimum decontamination conditions for the responses of S. putrefaciens and S. Typhimurium were P_V of 66 V, U_T of 14.90 min and T_P of 60 ℃, achieving reductions of 4.40 and 3.97 log CFU/g, respectively, with a desirability of 0.998. Among the variables, temperature presented higher significance for inactivating bacteria and the production of volatile basic nitrogen and lipid peroxidation under the optimized conditions were within the limits of freshness for grass carp. Additionally, the effects of PFB and the optimized thermoultrasound-assisted PFB decontamination were mild on the microstructure of grass carp with slight ruptures and loose myofibril structures, indicating the potential of thermoultrasound-assisted PFB for seafood products decontamination with reduced processing time.