Artificial rainfalls were used to determine the effect of the amount of the rainfall and the time... more Artificial rainfalls were used to determine the effect of the amount of the rainfall and the time interval between pesticide application and rainfall event, on folpet and mancozeb residues on grapes and vine leaves. Forty-five mm of rain were administered to the vineyard in different amounts (45; 30+15; 15+15+15 mm). Folpet showed good rainfastness on the grapes and on the leaves. A modest decrease was observed only in the experiments that had received 45 mm of rain at one go. Mancozeb showed a lower rainfastness, since a portion of the deposit was easily washed off also by a modest rainfall. The percentage of this portion was higher in the grapes (38%) than in the leaves (20%). The data obtained in these experiments show that, in the case of folpet, it is not necessary to repeat the treatment when it rains the day after, while it is recommendable to repeat it in the case of mancozeb.
The fate of three fungicide residues (fenamidone, pyraclostrobin, and trifloxystrobin) from vine ... more The fate of three fungicide residues (fenamidone, pyraclostrobin, and trifloxystrobin) from vine to wine was studied to evaluate the decay ratio and the influence of the technological process. The aim of this work was to identify pesticides that can degrade rapidly or be eliminated together with byproduct (lees and cake) of the winemaking process to obtain wine free of residues. The disappearance rate on grapes was calculated as pseudo-first-order kinetics, and the half-life (t(1/2)) was in the range from 5.4 +/- 1.9 to 12.2 +/- 1.2 days. The mechanism of dissipation of the three quinone outside inhibitor (QoI) fungicides was studied using different model systems. It was observed that the main mechanism responsible for disappearance was photodegradation. For active ingredients (ai) the half-lives of fenamidone, pyraclostrobin, and trifloxystrobin were 10.2 +/- 0.8, 20.1 +/- 0.1, and 8.6 +/- 1.0 h, respectively, whereas for formulation higher half-lives were observed when epicuticular waxes were present (from 13.8 +/- 0.2 to 26.6 +/- 0.1 h). After winemaking, fenamidone, pyraclostrobin, and trifloxystrobin residues were not detected in the wine, but they were present in the cake and lees. This was due to the adsorption of pesticide residues to the solid parts, which are always eliminated at the end of the alcoholic fermentation. The data obtained in these experiments suggest that these three active ingredients could be used in a planning process to obtain residue-free wines.
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2006
Famoxadone is a recently applied fungicide to vines that belongs to the oxazolidinedione family. ... more Famoxadone is a recently applied fungicide to vines that belongs to the oxazolidinedione family. The fate of famoxadone was studied by considering the decay ratio of this fungicide during the maturation of grapes and wine production. The main factors affecting the presence of fungicide residues such as fruit growth, photodegradation, evaporation, thermodegradation and co-distillation were studied with model systems. An
Famoxadone is a recent oxazolidinedione fungicide widely used in viticulture and in Integrated Pe... more Famoxadone is a recent oxazolidinedione fungicide widely used in viticulture and in Integrated Pest Management strategies. In this work, after a simple and fast liquid–liquid extraction (LLE), two new gas chromatographic methods were developed to analyze famoxadone residues in grapes and wines, one with electron-capture detection (GC-ECD) and the other with mass spectrometry (GC–MS). Global uncertainties for validation parameters of
An apiary trial was conducted in 1997 in Sardinia, Italy, to verify the effectiveness of fluvalin... more An apiary trial was conducted in 1997 in Sardinia, Italy, to verify the effectiveness of fluvalinate in polyvinyl chloride strips and flumethrin in polyethylene strips against Varroa jacobsoni Oudemans. Two indices to evaluate the efficacy of the treatments were adopted: percentage change in mite infestation of worker-sealed brood cells considering only treated hives and percentage change in mite mortality, and the natural variation in mite populations recorded in control hives during the trial. All acaricide treatments reduced the level of mite infestation of both sealed brood and adult bees. However, their effectiveness was slightly reduced in comparison to previous studies because of mite resistance phenomena. Portions of polyethylene strips of flumethrin from treated hives were sampled weekly to determine acaricide persistence using gas chromatography. After 4 wk, a slight reduction (approximately 9%) of the active ingredient content was observed. A laboratory bioassay also was performed to establish the resistance of adult female mites to fluvalinate. Mites were sampled from the experimental apiary and from various Sardinian apiaries which had primarily been subjected to fluvalinate applications in plastic strips or wood inserts for years. Mite resistance varied from 0 to 96%, depending on the acaricide management adopted. The lowest resistance level occurred in an apiary where pyrethroids had never been used, whereas the highest level occurred in an apiary, with intensive use of fluvalinate in wood inserts.
ABSTRACT Two formic acid autumnal treatments, gel packets (BeeVar formulation) and impregnated pa... more ABSTRACT Two formic acid autumnal treatments, gel packets (BeeVar formulation) and impregnated paperwick (Liebig-Dispenser), were tested in apiary to evaluate their effectiveness against Varroa destructor Anderson & Trueman and their residues in honey in a Mediterranean region (Sardinia, Italy). Both treatments were efficient in the apiary control of the varroosis, with values of percentage of mite mortality ranging between 93.6 and 100%, without statistical differences between them. The more gradual release of formic acid from the gel application allowed a longer action (2 wk for each treatment) compared with the Liebig-Dispenser (approximately 3d for each treatment). The rate of daily evaporation ranged between approximately 5 and 9 g/d from BeeVar and approximately 26 and 35 g/d from the Liebig-Dispenser, in the first and second treatment, respectively. The total amount of formic acid administered per hive during all the treatment period was approximately 200 g for either treatment. A significantly higher adult bee mortality was recorded in the Liebig-Dispenser-treated hives compared with the BeeVar-treated group. On the contrary, BeeVar treatment produced an interruption of brood reared, whereas the extension of the sealed brood area of the Liebig-Dispenser-treated hives was not significantly different from that of the control hives. Neither queen mortality nor robbing activity was observed due to the treatments. Formic acid residues in honey collected in the nest were 3,855 +/- 2,061 and 3,030 +/- 1,624 mg/kg for the BeeVar- and the Liebig-Dispenser-treated hives, respectively. After 21 d from the end of the treatment, the residues fell to 1,261 +/- 1,054 and 794 +/- 518 mg/kg for the honey sampled from the BeeVar and Liebig-Dispenser groups, respectively.
An HPLC method that allows the determination of complex phenolic compounds at low λ (225 nm) afte... more An HPLC method that allows the determination of complex phenolic compounds at low λ (225 nm) after solid-phase extraction from virgin olive oils is reported. The separation was achieved on ODS-2, ODS-1 and C8 columns in eluting mixtures 10−3M H2SO4CH3CN employed with different ratios. The method was employed for the quantitative determination of phenolic compounds in oils. It allows the
Journal of agricultural and food chemistry, Jan 5, 2003
Captan and its metabolite tetrahydrophthalimide (THPI) were determined in grapes, must, and wine ... more Captan and its metabolite tetrahydrophthalimide (THPI) were determined in grapes, must, and wine by GC-ITMS. Pesticides were extracted with acetone/petroleum ether (50:50 v/v). Because of the high selectivity of the ITMS detector, no interferent was found and cleanup was not necessary. Recoveries from fortified grapes, must, and wines ranged between 90 and 113% with a maximum coefficient of variation of 11%. Limits of quantitation were 0.01 mg/kg for both compounds. In model systems, captan and its metabolites, THPI, cis-4-cyclohexene-1,2-dicarboxylic acid, and 1,2,3,6-tetrahydrophthalamic acid, were determined by HPLC. The degradation of captan during winemaking was studied. Captan degraded in must, giving 100% THPI, and at the end of fermentation, only THPI was found in wine. The degradation of captan to THPI was due to the acidity in must and wine. This metabolite was present at low levels on grapes, and, unlike captan, it had no negative effect on the fermentative process. Model...
The fate of folpet from the treatment on vine to the production of wine was studied. Sunlight deg... more The fate of folpet from the treatment on vine to the production of wine was studied. Sunlight degraded folpet to unknown products. Phthalimide was a minor metabolite formed on grapes from folpet. Folpet degraded in must, giving 80% phthalimide; the results obtained with model ...
Field trials were carried out to evaluate whether folpet sprayed on grapevines penetrated the epi... more Field trials were carried out to evaluate whether folpet sprayed on grapevines penetrated the epicuticular wax and cell walls of grapes. Folpet showed poor penetration into the epicuticular wax; it was found almost totally on the surface. Despite its low solubility in water, perhaps due to the presence of adjuvants, its residues showed such a high resistance to washing that the action of rain was negligible in decreasing residues.
The influence of six fungicides (azoxystrobin, cyprodinil, fludioxonil, mepanipyrim, pyrimethanil... more The influence of six fungicides (azoxystrobin, cyprodinil, fludioxonil, mepanipyrim, pyrimethanil, and tetraconazole) on the fermentative activity of two yeasts (Saccharomyces cerevisiae and Kloeckeraapiculata) and two lactic bacteria (Leuconostoc oenos and Lactobacillus plantarum) was studied. The possibility of their being degraded by these yeasts and bacteria was also investigated. The presence of the pesticides did not affect alcoholic fermentation, not even with levels higher than those normally found in grapes in field experiments. On the contrary, their presence stimulated the yeast, especially K. apiculata, to produce more alcohol. The fermentative process did not affect the amount of pesticides either by degradation or by adsorption. During malolactic fermentation by Le. oenos, malic acid decreased slightly less (by approximately 15%) in the presence of all pesticides, except mepanipyrim. A lower effect ( approximately 5%) was found during the fermentative process with La. plantarum. The bacteria studied did not show a degradative effect on pesticides during malolactic fermentation.
A simple multiresidue method for screening analysis of 12 botanical insecticides used by organic ... more A simple multiresidue method for screening analysis of 12 botanical insecticides used by organic farmers has been developed. The method involves a rapid and small-scale extraction procedure with acetonitrile. For all fruit and vegetable samples, there was no need for clean up. Rotenone, azadirachtin, ryanodines, and pyrethrins can be separated by high-performance liquid chromatography, quantified, and confirmed with a diode array detector (DAD) and atmospheric pressure chemical ionization mass spectrometry (APCI-MS) in the select ion-monitoring mode (SIM). The majority of pesticide recoveries for various fruits and vegetables were >70% in the concentration range from 0.01 to 5 mg/kg. The limit of quantitation for most of the pesticides was 0.01 mg/kg, with the majority of relative standard deviations (RSD) mostly below 10%.
Artificial rainfalls were used to determine the effect of the amount of the rainfall and the time... more Artificial rainfalls were used to determine the effect of the amount of the rainfall and the time interval between pesticide application and rainfall event, on folpet and mancozeb residues on grapes and vine leaves. Forty-five mm of rain were administered to the vineyard in different amounts (45; 30+15; 15+15+15 mm). Folpet showed good rainfastness on the grapes and on the leaves. A modest decrease was observed only in the experiments that had received 45 mm of rain at one go. Mancozeb showed a lower rainfastness, since a portion of the deposit was easily washed off also by a modest rainfall. The percentage of this portion was higher in the grapes (38%) than in the leaves (20%). The data obtained in these experiments show that, in the case of folpet, it is not necessary to repeat the treatment when it rains the day after, while it is recommendable to repeat it in the case of mancozeb.
The fate of three fungicide residues (fenamidone, pyraclostrobin, and trifloxystrobin) from vine ... more The fate of three fungicide residues (fenamidone, pyraclostrobin, and trifloxystrobin) from vine to wine was studied to evaluate the decay ratio and the influence of the technological process. The aim of this work was to identify pesticides that can degrade rapidly or be eliminated together with byproduct (lees and cake) of the winemaking process to obtain wine free of residues. The disappearance rate on grapes was calculated as pseudo-first-order kinetics, and the half-life (t(1/2)) was in the range from 5.4 +/- 1.9 to 12.2 +/- 1.2 days. The mechanism of dissipation of the three quinone outside inhibitor (QoI) fungicides was studied using different model systems. It was observed that the main mechanism responsible for disappearance was photodegradation. For active ingredients (ai) the half-lives of fenamidone, pyraclostrobin, and trifloxystrobin were 10.2 +/- 0.8, 20.1 +/- 0.1, and 8.6 +/- 1.0 h, respectively, whereas for formulation higher half-lives were observed when epicuticular waxes were present (from 13.8 +/- 0.2 to 26.6 +/- 0.1 h). After winemaking, fenamidone, pyraclostrobin, and trifloxystrobin residues were not detected in the wine, but they were present in the cake and lees. This was due to the adsorption of pesticide residues to the solid parts, which are always eliminated at the end of the alcoholic fermentation. The data obtained in these experiments suggest that these three active ingredients could be used in a planning process to obtain residue-free wines.
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2006
Famoxadone is a recently applied fungicide to vines that belongs to the oxazolidinedione family. ... more Famoxadone is a recently applied fungicide to vines that belongs to the oxazolidinedione family. The fate of famoxadone was studied by considering the decay ratio of this fungicide during the maturation of grapes and wine production. The main factors affecting the presence of fungicide residues such as fruit growth, photodegradation, evaporation, thermodegradation and co-distillation were studied with model systems. An
Famoxadone is a recent oxazolidinedione fungicide widely used in viticulture and in Integrated Pe... more Famoxadone is a recent oxazolidinedione fungicide widely used in viticulture and in Integrated Pest Management strategies. In this work, after a simple and fast liquid–liquid extraction (LLE), two new gas chromatographic methods were developed to analyze famoxadone residues in grapes and wines, one with electron-capture detection (GC-ECD) and the other with mass spectrometry (GC–MS). Global uncertainties for validation parameters of
An apiary trial was conducted in 1997 in Sardinia, Italy, to verify the effectiveness of fluvalin... more An apiary trial was conducted in 1997 in Sardinia, Italy, to verify the effectiveness of fluvalinate in polyvinyl chloride strips and flumethrin in polyethylene strips against Varroa jacobsoni Oudemans. Two indices to evaluate the efficacy of the treatments were adopted: percentage change in mite infestation of worker-sealed brood cells considering only treated hives and percentage change in mite mortality, and the natural variation in mite populations recorded in control hives during the trial. All acaricide treatments reduced the level of mite infestation of both sealed brood and adult bees. However, their effectiveness was slightly reduced in comparison to previous studies because of mite resistance phenomena. Portions of polyethylene strips of flumethrin from treated hives were sampled weekly to determine acaricide persistence using gas chromatography. After 4 wk, a slight reduction (approximately 9%) of the active ingredient content was observed. A laboratory bioassay also was performed to establish the resistance of adult female mites to fluvalinate. Mites were sampled from the experimental apiary and from various Sardinian apiaries which had primarily been subjected to fluvalinate applications in plastic strips or wood inserts for years. Mite resistance varied from 0 to 96%, depending on the acaricide management adopted. The lowest resistance level occurred in an apiary where pyrethroids had never been used, whereas the highest level occurred in an apiary, with intensive use of fluvalinate in wood inserts.
ABSTRACT Two formic acid autumnal treatments, gel packets (BeeVar formulation) and impregnated pa... more ABSTRACT Two formic acid autumnal treatments, gel packets (BeeVar formulation) and impregnated paperwick (Liebig-Dispenser), were tested in apiary to evaluate their effectiveness against Varroa destructor Anderson & Trueman and their residues in honey in a Mediterranean region (Sardinia, Italy). Both treatments were efficient in the apiary control of the varroosis, with values of percentage of mite mortality ranging between 93.6 and 100%, without statistical differences between them. The more gradual release of formic acid from the gel application allowed a longer action (2 wk for each treatment) compared with the Liebig-Dispenser (approximately 3d for each treatment). The rate of daily evaporation ranged between approximately 5 and 9 g/d from BeeVar and approximately 26 and 35 g/d from the Liebig-Dispenser, in the first and second treatment, respectively. The total amount of formic acid administered per hive during all the treatment period was approximately 200 g for either treatment. A significantly higher adult bee mortality was recorded in the Liebig-Dispenser-treated hives compared with the BeeVar-treated group. On the contrary, BeeVar treatment produced an interruption of brood reared, whereas the extension of the sealed brood area of the Liebig-Dispenser-treated hives was not significantly different from that of the control hives. Neither queen mortality nor robbing activity was observed due to the treatments. Formic acid residues in honey collected in the nest were 3,855 +/- 2,061 and 3,030 +/- 1,624 mg/kg for the BeeVar- and the Liebig-Dispenser-treated hives, respectively. After 21 d from the end of the treatment, the residues fell to 1,261 +/- 1,054 and 794 +/- 518 mg/kg for the honey sampled from the BeeVar and Liebig-Dispenser groups, respectively.
An HPLC method that allows the determination of complex phenolic compounds at low λ (225 nm) afte... more An HPLC method that allows the determination of complex phenolic compounds at low λ (225 nm) after solid-phase extraction from virgin olive oils is reported. The separation was achieved on ODS-2, ODS-1 and C8 columns in eluting mixtures 10−3M H2SO4CH3CN employed with different ratios. The method was employed for the quantitative determination of phenolic compounds in oils. It allows the
Journal of agricultural and food chemistry, Jan 5, 2003
Captan and its metabolite tetrahydrophthalimide (THPI) were determined in grapes, must, and wine ... more Captan and its metabolite tetrahydrophthalimide (THPI) were determined in grapes, must, and wine by GC-ITMS. Pesticides were extracted with acetone/petroleum ether (50:50 v/v). Because of the high selectivity of the ITMS detector, no interferent was found and cleanup was not necessary. Recoveries from fortified grapes, must, and wines ranged between 90 and 113% with a maximum coefficient of variation of 11%. Limits of quantitation were 0.01 mg/kg for both compounds. In model systems, captan and its metabolites, THPI, cis-4-cyclohexene-1,2-dicarboxylic acid, and 1,2,3,6-tetrahydrophthalamic acid, were determined by HPLC. The degradation of captan during winemaking was studied. Captan degraded in must, giving 100% THPI, and at the end of fermentation, only THPI was found in wine. The degradation of captan to THPI was due to the acidity in must and wine. This metabolite was present at low levels on grapes, and, unlike captan, it had no negative effect on the fermentative process. Model...
The fate of folpet from the treatment on vine to the production of wine was studied. Sunlight deg... more The fate of folpet from the treatment on vine to the production of wine was studied. Sunlight degraded folpet to unknown products. Phthalimide was a minor metabolite formed on grapes from folpet. Folpet degraded in must, giving 80% phthalimide; the results obtained with model ...
Field trials were carried out to evaluate whether folpet sprayed on grapevines penetrated the epi... more Field trials were carried out to evaluate whether folpet sprayed on grapevines penetrated the epicuticular wax and cell walls of grapes. Folpet showed poor penetration into the epicuticular wax; it was found almost totally on the surface. Despite its low solubility in water, perhaps due to the presence of adjuvants, its residues showed such a high resistance to washing that the action of rain was negligible in decreasing residues.
The influence of six fungicides (azoxystrobin, cyprodinil, fludioxonil, mepanipyrim, pyrimethanil... more The influence of six fungicides (azoxystrobin, cyprodinil, fludioxonil, mepanipyrim, pyrimethanil, and tetraconazole) on the fermentative activity of two yeasts (Saccharomyces cerevisiae and Kloeckeraapiculata) and two lactic bacteria (Leuconostoc oenos and Lactobacillus plantarum) was studied. The possibility of their being degraded by these yeasts and bacteria was also investigated. The presence of the pesticides did not affect alcoholic fermentation, not even with levels higher than those normally found in grapes in field experiments. On the contrary, their presence stimulated the yeast, especially K. apiculata, to produce more alcohol. The fermentative process did not affect the amount of pesticides either by degradation or by adsorption. During malolactic fermentation by Le. oenos, malic acid decreased slightly less (by approximately 15%) in the presence of all pesticides, except mepanipyrim. A lower effect ( approximately 5%) was found during the fermentative process with La. plantarum. The bacteria studied did not show a degradative effect on pesticides during malolactic fermentation.
A simple multiresidue method for screening analysis of 12 botanical insecticides used by organic ... more A simple multiresidue method for screening analysis of 12 botanical insecticides used by organic farmers has been developed. The method involves a rapid and small-scale extraction procedure with acetonitrile. For all fruit and vegetable samples, there was no need for clean up. Rotenone, azadirachtin, ryanodines, and pyrethrins can be separated by high-performance liquid chromatography, quantified, and confirmed with a diode array detector (DAD) and atmospheric pressure chemical ionization mass spectrometry (APCI-MS) in the select ion-monitoring mode (SIM). The majority of pesticide recoveries for various fruits and vegetables were >70% in the concentration range from 0.01 to 5 mg/kg. The limit of quantitation for most of the pesticides was 0.01 mg/kg, with the majority of relative standard deviations (RSD) mostly below 10%.
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