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Application of ultrasound-assisted deep eutectic solvent extraction combined with liquid-liquid extraction method to the extraction of three pesticide residues from fruit and vegetable samples

Chen Sue, An Qi, Sun Hong, Mao Mengqian

Acta Chromatographica

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2021

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Vol. 33, no. 1

30--36

EN

A simple, inexpensive and sensitive method was developed for the simultaneous determination of three pesticide residues (carbendazim, thiophanate-methyl, and imidacloprid) in fruit and vegetable samples using high performance liquid chromatography (HPLC) based on a combined pretreatment of ultrasoundassisted deep eutectic solvent extraction (UA-DES-E) and liquid-liquid extraction (LLE). In this study, various types of deep eutectic solvents (DESs) were synthesized and the extraction efficiency was compared as extraction solvents. Results showed that glycerol-proline 5 9:4 (GP-5) obtained the highest extraction efficiency among different types of DESs. Experiment conditions, including DES volume, extraction time and pH, were systematically optimized using single-factor experiment. Under the optimum conditions, the limits of detection (LODs) and quantification (LOQs) were in the ranges of 0.05– 0.2 mg$mL1 and 0.1–0.5 mg$mL1, respectively. The relative recoveries of the three pesticides in the fruit and vegetable samples ranged from 85.7 to 113.0% at two spiked levels. Meanwhile, the method achieved excellent linearity with determination coefficients (r) greater than 0.999. Furthermore, the method was successfully applied to the analysis of the pesticides in real fruit and vegetable samples (apple, tomato, and grape).

2

Wybrane zastosowania ozonu w przemyśle spożywczym

Balawejder Maciej, Piechowiak Tomasz

Przemysł Spożywczy

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2019

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T. 73, nr 4

38--42

PL

Ozon jest alotropową odmianą tlenu o wysokiej reaktywności. Podstawowa metoda otrzymywania ozonu polega na zastosowaniu wyładowań elektrycznych (zwłaszcza cichych, koronowych i powierzchniowych), których energia powoduje jego powstawanie w strumieniu powietrza lub tlenu. Ozon w przemyśle stosowany jest formie gazowej lub jako roztwór wodny. Ze względu na swoje właściwości wykorzystywany jest w wielu gałęziach przemysłu jako środek odkażający oraz dezodorujący. Dzięki zdolności do rozkładu substancji organicznych znalazł również zastosowanie w przemyśle spożywczym, szczególnie do usuwania pozostałości pestycydów i wydłużania trwałości przechowalniczej surowców pochodzenia roślinnego. Dzięki ozonowaniu można także modyfikować wybrane parametry surowców przemysłu spożywczego, takie jak potencjał antyoksydacyjny, zawartość polifenoli czy aktywność enzymatyczna. Największą zaletą stosowania ozonu jest to, że nie powoduje dodatkowego zanieczyszczania, ponieważ w kontakcie z materiałami stałymi rozkłada się do tlenu cząsteczkowego.

EN

Ozone is a high reactive triatomic form of oxygen. The basic method of ozone generation base on the electric discharges (especially silent, corona and surface), which energy causes the formation of triatomic molecules in the air or oxygen stream. The ozone can be use in the industry as a gaseous form or as a solution. Ozone due to its properties, it could be used as a disinfectant or deodorizer in many industries. Ozone is able to degrade organic substances, and can be applied in the food industry, especially for removing pesticide residues and extending shelf life of raw materials of plant origin. Thanks to ozonization, the selected parameters of food industry raw materials, such as antioxidant potential, polyphenol content or enzymatic activity can also be modified. The biggest advantage of using ozone is that it does not cause additional fouling, because in contact with solid materials it decomposes into molecular oxygen.

3

Optimization and validation of a method based on derivatization with methylating agent followed by HPLC-DAD for determining dithiocarbamates residues

Zhou L., Xu J., Luan L., Ma J., Gong Y., Qin D., Pan C.

Acta Chromatographica

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2013

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Vol. 25, no. 4

613--625

EN

Dithiocarbamates fungicides (DTCs) are worldwidely used fungicides. Residue analytical methods on DTCs are usually based on headspace gas chromatography, which are not much stable and precise. In this study, a specific, simple and reliable method for determining DTCs fungicides residues was optimized and validated. The DTCs in foods and soils were extracted with an alkaline solution of EDTA and L-cysteine, followed by pH adjusting and methyl derivatization in methyl iodine solution. The organic layer of the reactants was separated, concentrated under vacuum and reconstructed in acetonitrile. DTCs residues were eluted on a C18 column and detected by HPLC-DAD at 272 nm. The S-alkyl derivatives of thiram, mancozeb and propineb were separated at different retention times. At fortified levels of 0.05 mg/kg to 2 mg/kg (residue expressed as CS2, in mg/kg, the same below), it is found that recoveries for DTCs spiked in apple, cucumber, tomato, rice and soil samples ranged from 70.8% to 105.3%, with relative standard deviations (RSD) from 0.6% to 13.7%. Limits of detection (LODs) and quantification (LOQs) ranged from 0.003 to 0.026 mg/kg and from 0.011 to 0.105 mg/kg for various foods and soils. This method was also applied to real sample tests.

4

Occupational Safety of Farmers in the Vegetable Industry

Lu J. L. D. P.

International Journal of Occupational Safety and Ergonomics

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2011

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Vol. 17, No. 4

445--453

EN

This study aimed to determine unsafe farming practices, nonergonomically designed equipment, and possible adverse health effects of pesticide exposure. Data were gathered with a structured survey, physical examination and blood extraction. Environmental monitoring was done for vegetables to determine multipesticide residue. Forty-eight percent of respondents reported feeling sick because of work. Vegetable residue was found in 16.67% of the samples. Vegetable profenofos of ~1 mg exceeded the necessary average daily intake of a maximum of 0.006 mg. Data also showed nonergonomically designed tools and unsafe work practices that increased pesticide exposure such as re-entering recently sprayed areas, a damaged backpack sprayer, spills during spraying, and no ventilation in greenhouses.