Reversed-phase high-performance liquid chromatography of pesticides. VII. Analysis of Vinclozolin, Iprodione, Procymidone, Dichlozolinate and their degradation product 3,5-dichloroaniline on white must and wine extracts

Occurrence and impact of fungicides residues on fermentation during wine production- A review

Continuous fungicide spraying is required to eliminate fungal pathogens on grapes. However, this practice is associated with several risks, including contamination and environmental imbalance, as well as toxicity to operators and the induction of resistance in pathogens. In addition, a strong correlation has been reported between the presence of fungicides and the occurrence of issues during alcoholic fermentation, resulting in negative impacts on the sensory quality of the final products. Numerous studies have evaluated residue concentrations of phytosanitary products in grapes, juices, and wines, and a significant number of studies have assessed the impact of different agrochemicals on bioprocesses. However, a review compiling the key results of these studies is currently lacking. This review incorporates results obtained in the last decade from research on the presence of fungicide residues, including azoxystrobin, boscalid, captan, copper, fenhexamid, folpet, pyraclostrobin, pyrimethanil and tebuconazole, and their effects on fermentation kinetics. Practical solutions to mitigate these problems, both in vineyards and industry, are also presented and discussed. This review highlights the constant high fungicidal agent concentrations (greater than 1 or 2 mg L^-1) used throughout the winemaking process, with the impact of residues being of particular concern, especially with regard to their effect on yeast activity and the fermentation process. Thus, the adoption of methodologies that allow winemakers to control and trace these residues is an important step in avoiding or reducing fermentation problems throughout the winemaking process.[Figure: see text].

Biotransformation of vinclozolin in rat precision-cut liver slices: comparison with in vivo metabolic pattern

Vinclozolin is a dicarboxymide fungicide that presents antiandrogenic properties through its two hydrolysis products M1 and M2, which bind to the androgen receptor. Because of the lack of data on the biotransformation of vinclozolin, its metabolism was investigated in vitro in precision-cut rat liver slices and in vivo in male rat using [ (14)C]-vinclozolin. Incubations were performed using different concentrations of substrate, and the kinetics of formation of the major metabolites were studied. Three male Wistar rats were fed by gavage with [ (14)C]-VZ. Urine was collected for 24 h and analyzed by radio-HPLC for metabolic profiling. Metabolite identification was carried out on a LCQ ion trap mass spectrometer. In rat liver slices and in vivo, the major primary metabolite has been identified as 3',5'-dichloro-2,3,4-trihydroxy-2-methylbutyranilide (M5) and was mainly present as glucuronoconjugates. M5 is produced by dihydroxylation of the vinyl group of M2. Other metabolites have been identified as 3-(3,5-dichlorophenyl)-5-methyl-5-(1,2-dihydroxyethyl)-1,3-oxazolidine-2,4-dione (M4), a dihydroxylated metabolite of vinclozolin, which undergoes further conjugation to glucuronic acid, and 2-[[(3,5-dichlorophenyl)-carbamoyl]oxy]-2-methyl-3,4-dihydroxy-butanoic acid (M6), a dihydroxylated metabolite of M1.

Mass spectrometry in grape and wine chemistry. Part II: The consumer protection

Controls in food industry are fundamental to protect the consumer health. For products of high quality, warranty of origin and identity is required and analytical control is very important to prevent frauds. In this article, the "state of art" of mass spectrometry in enological chemistry as a consumer safety contribute is reported. Gas chromatography-mass spectrometry (GC/MS) and liquid-chromatography-mass spectrometry (LC/MS) methods have been developed to determine pesticides, ethyl carbamate, and compounds from the yeast and bacterial metabolism in wine. The presence of pesticides in wine is mainly linked to the use of dicarboxyimide fungicides on vineyard shortly before the harvest to prevent the Botrytis cinerea attack of grape. Pesticide residues are regulated at maximum residue limits in grape of low ppm levels, but significantly lower levels in wine have to be detected, and mass spectrometry offers effective and sensitive methods. Moreover, mass spectrometry represent an advantageous alternative to the radioactive-source-containing electron capture detector commonly used in GC analysis of pesticides. Analysis of ochratoxin A (OTA) in wine by LC/MS and multiple mass spectrometry (MS/MS) permits to confirm the toxin presence without the use of expensive immunoaffinity columns, or time and solvent consuming sample derivatization procedures. Inductively coupled plasma-mass spectrometry (ICP/MS) is used to control heavy metals contamination in wine, and to verify the wine origin and authenticity. Isotopic ratio-mass spectrometry (IRMS) is applied to reveal wine watering and sugar additions, and to determine the product origin and traceability.

Theoretical Study on the Complete Series of Chloroanilines

The environmental effects of chloroanilines depend on their physical and chemical properties, and it is therefore important to know their structure-property relationships that allow a complete understanding of their environmental consequences. The chemical reactivity profiles of all 19 chloroanilines have been investigated using the density functional theory for the first time. Global reactivity descriptors, such as hardness, chemical potential, electrophilicity index, and polarizability, and local reactivity descriptors, namely, local philicities, have been calculated in order to gain insights into the reactive nature and the reactive sites of the selected systems. Using AIM theory, the presence of hydrogen bond critical points (HBCPs) and the values of electron density and Laplacian of electron density at the HBCPs have been analyzed to appreciate the presence of intramolecular hydrogen bonding in the selected systems. Structure-toxicity analysis of the selected set of chloroanilines demonstrates the importance of the electrophilicity index in the prediction of reactivity/toxicity.

Toxicity effects of fungicide residues on the wine-producing process

We report the detection of several fungicide residues (Dichlofluanid, Benomyl, Iprodione, Procymidone and Vinclozolin) in red and white bottled wines from two Portuguese wine-producing zones. Studies were done in order to evaluate the active compound transfer percentage from grapes to the final product along fermentation process. We also investigated their effects in Saccharomyces and non-Saccharomyces yeasts as well as their influence on the physical, chemical and organoleptic wine properties. All the tested fungicides had a negative effect on in vitro yeast growth, with Dichlofluanid and Benomyl being the most toxic. Zygosaccharomyces rouxii and Saccharomyces cerevisiae were the most resistant yeasts while Rhodotorula glutinis was the most susceptible. Microvinification experiments carried out in the presence of fungicides produced wine samples with unaltered physical, chemical and organoleptic properties, though Benomyl, a slight delay in the initiation of fermentation process was observed.

Determination of impurities in pesticides and their degradation products formed during the wine-making process by solid-phase extraction and gas chromatography with detection by electron impact mass spectrometry. I. Vinclozoline, procymidone and fenitrothion

The presence of degradation products of vinclozoline, procymidone and fenitrothion, and of impurities from their commercial formulations, was studied in white and red wines elaborated from spiked must. After solid-phase extraction the nature of the residues was established by gas chromatography with mass spectrometric detection. The structures of several degradation products and impurities are discussed and elucidated on the basis of their electron impact spectra. In elaborated wines the concentrations of the degradation products and impurities are lower than those of the original active ingredients. Aminofenitrothion and acetylamino-formyl-fenitrothion-oxon are the main residues of fenitrothion in wine. For dicarboximides, an alcohol derivative of vinclozoline was found in addition to 3,5-dichloroaniline.

Multiresidue method for fourteen fungicides in white grapes by liquid-liquid and solid-phase extraction followed by liquid chromatography-diode array detection

A quantitative, selective and sensitive HPLC method for the analysis of 14 fungicides in white grapes for vinification is described. The proposed method is based on liquid-liquid extraction (LLE) and solid-phase extraction (SPE) followed by liquid chromatography and diode array detection (HPLC-DAD). Dichloromethane-acetone (75:25, v/v) was the most appropriate solvent mix for extracting fungicides in white grapes. Silica cartridges resulted the most appropriate for extract purification purposes. Quality parameters of the proposed multiresidue method presented good recovery (ca. 85% for almost all target compounds) and precision (between 1.5 and 16%), and detection limits lower than maxima residual limits set by the 76/895/ECC and 90/642/ECC Directive. Five different white grapes for vinification produced in Rias Baixas area in Galicia (NW Spain) were analyzed in order to assess the performance of the method with real samples and to determine whether the concentration of the pesticides used exceed their maxima residue levels (MRLs). Results showed that grape concentrations for those identified fungicides were lower than those established by European legislation.

Simultaneous reversed-phase high-performance liquid chromatographic separation of mono-, di-and trichloroanilines through a gradient elution optimised by experimental design

A new RP-HPLC method for the simultaneous determination of the 13 mono-, di- and trichloroanilines has been developed. In order to obtain the analyte resolution within an acceptable analysis time, a gradient elution program has been optimised through the use of an experimental design and a grid search algorithm. The optimized conditions provided the resolution of all the analytes in less than 80 min. The primary validation of the analytical method gave limit of detection values ranging between 0.02 and 0.06 mg/l and very good linearity of the calibration curves.

Solid-phase microextraction-gas chromatographic-mass spectrometric method for the determination of the fungicides cyprodinil and fludioxonil in white wines

A solid-phase microextraction (SPME) followed by a gas chromatographic-mass spectrometric (GC-MS) determination has been developed and validated for the determination of cyprodinil and fludioxonil in white wine samples. Extraction parameters such as the selection of SPME coating, the effect of the temperature, the effect of the headspace volume and the salt addition were studied and optimized, together with GC-MS analytical conditions. The divinylbenzene-Carboxen-polydimethylsiloxane (DVB-CAR-PDMS) fiber was the most appropriate for the determination of the two pesticides in wine. The quality parameters of the proposed method demonstrated a good precision (RSD about 5%), with detection limits of 0.1 and 0.2 microg/l for cyprodinil and fludioxonil, respectively. Fifteen commercial white wine samples produced in Rías Baixas area in Galicia (N.W. Spain) were analyzed with the SPME-GC-MS procedure. Some of the commercial wines (75%) presented the two pesticides in concentrations ranging from 0.9 to 28.6 microg/l. In conclusion, SPME-GC-MS has a great potential for fungicide determination in wines.

Determination and identification of metabolites of the fungicides Iprodione and Procymidone in compost

The main metabolites formed from Iprodione and Procymidone during the composting process have been isolated and identified by HPLC-DAD-MSD. After addition of the fungicides to the composting pile, we monitored the reaction of the two analytes and the formation of their degradation products for eight months. We verified the nature of the metabolites by comparison with those hypothesised in the literature and by comparison with the behaviour of an abiotic process in aqueous acetonitrile pH 6 and at 35 degrees C. After taking into account the different kinetic behaviours of the fungicides on degradation in compost and hydro-organic solution, breakdown pathways are proposed for biodegradation.

Determination of presence of fungicides by their common metabolite, 3,5-DCA, in compost

This paper describes the determination of 3,5-DCA in commercial composts, a common metabolite in a class of fungicides, and dicarboximides (Vinclozolin, Chlozolinate, Iprodione, Procymidone) which are commonly used in agriculture. The extracts, obtained in acetonitrile by sonication, are analysed by HPLC/DAD without clean-up. This method has shown several advantages: reduced manipulation of samples, good recovery (80-90%) and good reproducibility (RSD% <7). The limit of detection (DL) of the analytical method has been estimated as 15 microg/kg for the common metabolite, and 35-145 microg/kg for the four fungicides in the matrices.

Multiresidue analysis of seventeen pesticides in wine by gas chromatography with mass-selective detection

We have developed a multiresidue method permitting the simultaneous quantitation of 17 pesticides in wine: dicloran, dimethoate, diazinon, chlorpyrifos-methyl, vinclozolin, carbaryl, methiocarb, dichlofluanid, parathion-ethyl, triadimefon, procymidone, myclobutanil, iprodione, imidan, dicofol, phosalone and azinphos-methyl. Solid-phase extraction of 0.5 ml of wine sample is followed by direct injection of 1 microl of the eluent onto a DB-5 MS gas chromatographic column followed by mass-selective detection using one target and two qualifier ions for each pesticide. The extraction and injection steps are carried out with automatic instrumentation. Good resolution of all compounds was achieved with a run-time approximating 23 min. Detection and quantitation limits were around 2 microg/l and 10 microg/l, respectively, with linear calibration curves up to 3 mg/l for most constituents. Recovery in half the compounds was >90%, and >80% in most of the remainder. Imprecision (relative standard deviation) was <10% for most pesticides and <18% in all. Further analytes can be added to the repertoire without difficulty. The method merits consideration together with four other multiresidue methods now available that offer similar analytical characteristics, slower run-times, and a different selection of analytes.

Field trials to determine residues of chlozolinate in table grapes

Chlozolinate (Serinal) is a dicarboximide fungicide used in southern European countries principally on grapes. Maximum residue levels have not yet been set by FAO/WHO and are under evaluation in the EU. Field trials have been carried out in Greece on two varieties of table grapes (Cardinal and Victoria) during two consecutive years to assess residues remaining after application according to good agricultural practice. Analysis using a multiresidue method with gas chromatography (ECD) showed that the parent compound decays with a first-order rate constant of 0.057 +/- 0.011 day(-)(1) and that residues had fallen below the proposed MRL of 5 mg/kg in all samples by 21 days postapplication (the proposed PHI). The contribution of the main metabolite, S1, to the total residue is generally <20%. Washing removes a substantial amount (up to 80%) of chlozolinate, which appears to be nonsystemic on grapes, thus reducing real consumer exposure to this pesticide.

Determination of the fungicide vinclozolin in honey and bee larvae by solid-phase and solvent extraction with gas chromatography and electron-capture and mass spectrometric detection

Methods for the determination of residual vinclozolin in honey and bee larvae are proposed. The fungicide can be extracted with an n-hexane-acetone (70:30, v/v) mixture, or by passage through ODS cartridges which requires no subsequent clean-up. Vinclozolin is quantified by capillary gas chromatography with electron-capture and mass spectrometric detection. Recoveries from spiked samples exceed 90%, with a relative standard deviation of 3.5-4.5%.

3,5-Dichloroaniline toxicity in Fischer 344 rats pretreated with inhibitors and inducers of cytochrome P450

3,5-Dichloroaniline (3,5-DCA), a derivative needed in the manufacture of dyes, pesticides and industrial compounds has been reported to induce renal damage. This study investigated whether pretreatment with inducers or inhibitors of P450 altered 3,5-DCA toxicity. P450 levels were induced in male Fischer 344 rats (4-12/group) by pretreatment (i.p.) with phenobarbital (PB, 75 mg/kg/day for 3 days), beta-naphthoflavone (BNF, 100 mg/kg/day for 4 days) or pyridine (PYR, 100 mg/kg/day for 4 days). P450 activity was inhibited by pretreatment with piperonyl butoxide (PiBx) 30 min prior to injection of 3,5-DCA. Upon completion of a designated pretreatment regimen, 0.4 or 0.8 mmol/kg 3,5-DCA was injected into F344 rats. Pair-fed controls were injected with 25% ethanol solution or physiological saline (2.5 ml/kg). The renal changes monitored at 24 and 48 h following treatment with 0.8 mmol/kg 3,5-DCA were characterized by increased blood urea nitrogen (BUN) level and decreased renal cortical slice accumulation of p-aminohippurate (PAH). Plasma alanine transaminase activity (ALT/GPT) was increased 24 h after injection of 0.8 mmol/kg 3,5-DCA while liver wt. was unchanged. PB or PYR pretreatment did not alter the renal or hepatic effects of 3,5-DCA while BNF pretreatment slightly reduced toxicity. In contrast, PiBx pretreatment increased the renal and hepatic changes associated with 3,5-DCA. The results with PiBx suggest that either the parent compound possesses some direct cytotoxicity or that a toxic metabolite was generated through a biotransformation pathway not inhibited by PiBx.

Chemical ionization mass spectrometry of iprodione and its metabolites

One of the cornerstones of an architectural approach adopted by this laboratory in screening vegetables for pesticides and industrial chemicals is the extensive use of element-selective gas chromatographic detectors followed by gas chromatography/mass spectrometry. In this particular case history, a recently introduced European fungicide, iprodione, was thought to be the first reported incidence in mache imported from France. An analytical protocol involving chemical ionization was devised to confirm this finding as well as search for possible potential metabolites.