Publications (94)161.5 Total impact
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Article: Control of postharvest diseases of fruit by heat and fungicides: efficacy, residue levels, and residue persistence. A review.
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ABSTRACT: Extensive research has been done in recent years to reduce the heavy dependence on chemical fungicides to control postharvest diseases and disorders of horticultural crops. Alternative strategies were based on improved cultural practices, biological control, plant-defense promoters, and physical treatments such as UV illumination, radiofrequency treatment, heat therapy, and storage technologies. Among these, postharvest heat treatments such as hot water dips, short hot water rinsing and brushing, and hot air conditioning have reduced rot development and enhanced fruit resistance to chilling injury in sensitive cultivars while retaining fruit quality during cold storage and shelf life. Additive or synergistic increases in effectiveness were observed by integrating heat therapy with various chemical compounds, thus leading to significant reductions in the application of active ingredients to protect produce from decay. This paper highlights the knowledge on this topic with emphasis on heat therapy effects and factors affecting the uptake, persistence, and performance of fungicide residues when they are applied in combination with hot water.Journal of Agricultural and Food Chemistry 08/2011; 59(16):8531-42. · 2.82 Impact Factor -
Article: Chlorpyrifos residues levels in fruits and vegetables after field treatment.
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ABSTRACT: Chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate) was applied with three different formulations on oranges, peaches, tomatoes, wine and table grapes, and its behaviour was evaluated after field treatment. The formulations applied were emulsifiable concentrates (EC), microencapsulates (ME), and wettable granules (WG). The residues were similar in all crops studied in the EC and WG experiments, except peaches with WG treatment, the residue amount was lower than EC values. Tomatoes which were grown in greenhouse showed similar residues in all treatments just after treatment. Wine and table grapes showed different decline curves in the EC experiments ascribable to the different growing technology. Instrumental limit of determination (LOD) and limit of quantification (LOQ) for all matrices were 0.01, and 0.03 mg kg⁻¹, respectively. Repeated treatments showed that Chlorpyrifos can accumulate leading to residue levels at the preharvest interval (PHI) over the maximum residue level (MRL), especially on oranges and peaches. Among the formulates used ME showed the higher risk of residues over the MRL at harvest.Journal of Environmental Science and Health Part B Pesticides Food Contaminants and Agricultural Wastes 08/2011; 46(6):544-9. · 1.10 Impact Factor -
Article: Minor crops for export: a case study of boscalid, pyraclostrobin, lufenuron and lambda-cyhalothrin residue levels on green beans and spring onions in Egypt.
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ABSTRACT: Dissipation rates of boscalid [2-chloro-N-(4' -chlorobiphenyl-2-yl)nicotinamide], pyraclostrobin [methyl 2-[1-(4-chlorophenyl) pyrazol-3-yloxymethyl]-N-methoxycarbanilate], lufenuron [(RS)-1-[2,5-dichloro-4-(1,1,2,3,3,3-hexafluoropropoxy)phenyl]-3-(2,6-difluorobenzoyl)urea] and lambda-cyhalothrin [(R)-cyano(3-phenoxyphenyl)methyl (1S,3S)-rel-3-[(1Z)-2-chloro-3,3,3-trifluoro-1-propenyl]-2,2-dimethylcyclopropanecarboxylate] in green beans and spring onions under Egyptian field conditions were studied. Field trials were carried out in 2008 in a Blue Nile farm, located at 70 kilometer (km) from Cairo (Egypt). The pesticides were sprayed at the recommended rate and samples were collected at pre-determined intervals. After treatment (T(0)) the pesticide residues in green beans were 7 times lower than in spring onions. This is due to a different structure of vegetable plant in the two crops. In spring onions, half-life (t(1/2)) of pyraclostrobin and lufenuron was 3.1 days and 9.8 days respectively. At day 14th (T(14)) after treatment boscalid residues were below the Maximum Residue Limit (MRL) (0.34 versus 0.5 mg/kg), pyraclostrobin and lambda -cyhalothrin residues were not detectable (ND), while lufenuron residues were above the MRL (0.06 versus 0.02 mg/kg). In green beans, at T(0), levels of boscalid, lufenuron and lambda -cyhalothrin were below the MRL (0.28 versus 2 mg/kg; ND versus 0.02 mg/kg; 0.06 versus 0.2 mg/kg, respectively) while, after 7 days treatment (T(7)) pyraclostrobin residues were above the MRL (0.03 versus 0.02 mg/kg). However, after 14 days the residue level could go below the MRL (0.02 mg/kg), as observed in spring onions.Journal of Environmental Science and Health Part B Pesticides Food Contaminants and Agricultural Wastes 08/2010; 45(6):493-500. · 1.10 Impact Factor -
Article: Liquid chromatography electrospray ionization tandem mass spectrometric determination of quassin and neoquassin in fruits and vegetables.
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ABSTRACT: Quassia amara wood chips are used by organic farmers as a valid alternative to synthetic insecticides. The powder of Q. amara contains high levels of quassin, neoquassin and picrasinoside B. In this study we developed a liquid chromatography mass spectrometry method for the rapid and accurate quantification of the insecticide quassinoids on fruits and vegetables. Quassinoids were extracted from fruits and vegetables with acetonitrile and separated on a Zorbax Column Eclipse XDB C8 by isocratic elution with a mobile phase consisting of water and methanol with 0.1% of formic acid. Using a high-performance liquid chromatograph coupled with an electrospray ionization tandem mass spectrometer (HPLC/ESI-MS/MS), quassinoids were selectively and simultaneously detected monitoring the multiple reaction (MRM) transitions of proton adduct precursor ions: m/z 389.5 --> 222.9 for quassin, 391.5 --> 372.9 for neoquassin and 576.1 --> 394.5 for picrasinoside B. For all quassinoids calibration was linear over a working range of 1 and 100 microg/kg with r > 0.991. Limit of determination (LOD) and limit of quantification (LOQ) for both quassinoids were 0.5 and 1 microg/kg respectively while for picrasinoside B they were 5 and 10 microg/kg. Quassinoid recoveries ranged from 85.3% to 105.3% with coefficients of variation between 2.5% and 12.8% for fruit and vegetables. The presence of interfering compounds in the fruit and vegetable extract was evaluated and found to be minimal. Due to the linear behavior it was concluded that the multiple reaction transitions of precursor ions can be used for analytical purposes, i.e. for identification and quantification of quassin, neoquassin, and picrasinoside B in fruit and vegetable extracts at trace levels.Journal of Agricultural and Food Chemistry 03/2010; 58(5):2807-11. · 2.82 Impact Factor -
Article: Postinfection activity, residue levels, and persistence of azoxystrobin, fludioxonil, and pyrimethanil applied alone or in combination with heat and imazalil for green mold control on inoculated oranges.
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ABSTRACT: The postinfection activity of azoxystrobin (AZX), fludioxonil (FLU), and pyrimethanil (PYR), applied alone or in combination with imazalil (IMZ), in controlling postharvest green mold in 'Salustiana' oranges inoculated with Penicillium digitatum was studied. Fruits were immersed for 30 or 60 s in (i) water or water mixtures at 20 degrees C containing AZX, FLU, or PYR at 600 mg/L; and (ii) IMZ at 600 mg/L, alone or in combination with AZX, FLU, or PYR at 600 mg/L. Similar treatments were performed at 50 degrees C using the active ingredients at half rates with respect to the treatments at 20 degrees C. Fungicide residues in fruits were analyzed following treatments and after 14 days of simulated shelf life at 17 degrees C. AZX or FLU mixtures at 20 degrees C for 30-60 s similarly but moderately reduced green mold decay with respect to control fruit; differences due to dip time were not significant. Superior control of decay was achieved by PYR and, especially, IMZ, applied alone or in combination with AZX, FLU, or PYR. The activity of PYR at 20 degrees C was significantly dependent on treatment time, whereas that of IMZ and combined treatments at 20 degrees C was not. The effectiveness of FLU or PYR mixtures at 50 degrees C in controlling decay was similar and superior to that of AZX. The action of single- or double-fungicide application was not dependent on dip time in most samples. IMZ or combined mixtures at 50 degrees C were consistently more effective with respect to single-fungicide treatments with AZX, FLU, or PYR. The application of heated fungicide mixtures resulted in significantly higher residue accumulation in most fruit samples compared to treatments performed at 20 degrees C. The degradation rate of fungicides was generally low and dependent on treatment conditions such as time, temperature, and the presence or not of other fungicides.Journal of Agricultural and Food Chemistry 02/2010; 58(6):3661-6. · 2.82 Impact Factor -
Article: Chemical variability, antifungal and antioxidant activity of Eucalyptus camaldulensis essential oil from Sardinia.
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ABSTRACT: Essential oil (EO) from aerial parts of Eucalyptus camaldulensis Dehnh., growing wild in different localities of Sardinia (Italy), was extracted by steam distillation and analyzed by gas chromatography (GC) FID and GC-ion trap mass spectrometry (ITMS). The yields of EO (v/dry wt) ranged between 0.2-0.5%. Samples were harvested between April and December to study the seasonal chemical variability of the EO. The chemical composition varied depending on the different origins and showed strong fluctuation during the vegetative stage. Thirty-seven compounds, accounting for at least 97.7% of the total EOs were identified, the major components being p-cymene (27.8-42.7%), 1,8-cineole (4.1-39.5%), beta-phellandrene (3.9-23.8%), spathulenol (2.1-15.5%) and cryptone (3.2-10.2%). The oils possessed moderate amounts (1.4-4.7%) of two uncommon aldehydes, cuminal and phellandral. The essential oils were screened for their antifungal activities against common phytopathogenic fungi using the paper disk diffusion method and they showed activity at low doses against the fungi tested. The antioxidant activity, assessed by DPPH-test and expressed as Trolox equivalent antioxidant capacity, showed values ranging between 0.5 and 5.8 mmol/L.Natural product communications 02/2010; 5(2):329-35. · 1.24 Impact Factor -
Article: Pesticides' influence on wine fermentation.
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ABSTRACT: Wine quality strongly depends on the grape quality. To obtain high-quality wines, it is necessary to process healthy grapes at the correct ripeness stage and for this reason the farmer has to be especially careful in the prevention of parasite attacks on the grapevine. The most common fungal diseases affecting grape quality are downy and powdery mildew (Plasmopara viticola and Uncinula necator), and gray mold (Botrytis cinerea). On the other hand, the most dangerous insects are the grape moth (Lobesia botrana), vine mealybug (Planococcus ficus), and the citrus mealybug (Planococcus citri). Farmers fight grape diseases and insects applying pesticides that can be found at harvest time on grapes. The persistence of pesticides depends on the chemical characteristic of the active ingredients as well as on photodegradation, thermodegradation, codistillation, and enzymatic degradation. The pesticide residues on grapes can be transferred to the must and this can influence the selection and development of yeast strains. Moreover, yeasts can also influence the levels of the pesticides in the wine by reducing or adsorbing them on lees. During the fermentative process, yeasts can cause the disappearance of pesticide residues by degradation or absorption at the end of the fermentation when yeasts are deposited as lees. In this chapter, we reviewed the effect of commonly used herbicides, insecticides, and fungicides on yeasts. We also studied the effect of alcoholic and malolactic fermentation on pesticide residues.Advances in food and nutrition research 01/2010; 59:43-62. -
Article: Floral markers of strawberry tree (Arbutus unedo L.) honey.
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ABSTRACT: Strawberry tree honey, due to its characteristic bitter taste, is one of the most typical Mediterranean honeys, with Sardinia being one of the largest producers. According to specific chemical studies, homogentisic acid was identified as a possible marker of this honey. This work, based on HPLC-DAD-MS/MS analysis of strawberry tree (Arbutus unedo L.) honeys, previously selected by sensory evaluation and melissopalynological analysis, showed that, in addition to the above-mentioned acid, there were other high levels of substances useful for the botanical classification of this unifloral honey. Two of these compounds were isolated and identified as (+/-)-2-cis,4-trans-abscisic acid (c,t-ABA) and (+/-)-2-trans,4-trans-abscisic acid (t,t-ABA). A third compound, a new natural product named unedone, was characterized as an epoxidic derivative of the above-mentioned acids. Structures of c,t-ABA, t,t-ABA, and unedone were elucidated on the basis of extensive 1D and 2D NMR experiments, as well as HPLC-MS/MS and Q-TOF analysis. In selected honeys the average amounts of c,t-ABA, t,t-ABA, and unedone were 176.2+/-25.4, 162.3+/-21.1, and 32.9+/-7.1 mg/kg, respectively. Analysis of the A. unedo nectar confirmed the floral origin of these compounds found in the honey. Abscisic acids were found in other unifloral honeys but not in such high amount and with a constant ratio of about 1:1. For this reason, besides homogentisic acid, these compounds could be used as complementary markers of strawberry tree honey.Journal of Agricultural and Food Chemistry 11/2009; 58(1):384-9. · 2.82 Impact Factor -
Article: Influence of post-harvest application rates of cyprodinil, treatment time and temperature on residue levels and efficacy in controlling green mould on 'Valencia' oranges.
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ABSTRACT: The effectiveness of heat treatments with water and cyprodinil in controlling post-harvest green mould caused by Penicillium digitatum was investigated on artificially inoculated 'Valencia' oranges. Residue levels of cyprodinil were determined in the oranges as a function of active ingredient concentration, temperature and treatment time. Cyprodinil residues were significantly dependent on treatment time when applied at 600 mg l(-1) and 20 degrees C, but not when fruit were treated at 150-300 mg l(-1). The application of cyprodinil at 50 or 100 mg l(-1) at 55 degrees C for 30 s produced similar residue levels, while residues increased when the application rate was 150 mg l(-1). Cyprodinil at 100 mg l(-1) and 60 degrees C produced a significant increase in residues compared to treatment at 50 mg l(-1); no significant increase in residues was found when the application rate was raised from 100 to 150 mg l(-1). In comparison to treatments performed at 20 degrees C, the application of a heated cyprodinil mixture resulted in significantly higher residues in fruit. All treatments with cyprodinil at 20 degrees C similarly reduced green mould after 7 days of storage at 20 degrees C. After 18 days, treatment with cyprodinil at 600 mg l(-1) for 30 s was more effective than at 150-300 mg l(-1). When dip time was extended to 90 or 180 s, treatment efficacy was positively related to fungicide concentration. Treatments with water at 55 degrees C for 30 s were as effective as cyprodinil at 50-100 mg l(-1), but less effective than cyprodinil at 150 mg l(-1). After 7 days, treatment with water or cyprodinil at 50-150 mg l(-1) and 60 degrees C were equally effective in controlling green mould; while, after 18 days, treatment with cyprodinil at 150 mg l(-1) was consistently more effective than at 50-100 mg l(-1) or hot water alone.Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment 08/2009; 26(7):1033-7. -
Article: Fate of azadirachtin A and related azadirachtoids on tomatoes after greenhouse treatment
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ABSTRACT: The degradation of the main azadirachtoids on tomatoes was studied after greenhouse treatment. These experiments were carried out at 1 and 5× the concentration recommended by the manufacturer. In all experiments the deposition of azadirachtin A (AZA-A) was below the maximum residue level (MRL). Even if at the highest dose, AZA-A half-life time calculated as pseudo first order kinetic was 1.2 days in agreement with the recommended preharvest interval (PHI) of 3 days. Experiments with a model system showed that sunlight photodegradation is the main factor influencing the rate of disappearance of AZA-A after greenhouse treatment while tomato epicuticular waxes doubled the photodegradation rate of AZA-A in a commercial formulation.Journal of Environmental Science and Health. 08/2009; Part B(Vol. 44):598-605. -
Article: Fate of azadirachtin A and related azadirachtoids on tomatoes after greenhouse treatment.
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ABSTRACT: The degradation of the main azadirachtoids on tomatoes was studied after greenhouse treatment. These experiments were carried out at 1 and 5x the concentration recommended by the manufacturer. In all experiments the deposition of azadirachtin A (AZA-A) was below the maximum residue level (MRL). Even if at the highest dose, AZA-A half-life time calculated as pseudo first order kinetic was 1.2 days in agreement with the recommended preharvest interval (PHI) of 3 days. Experiments with a model system showed that sunlight photodegradation is the main factor influencing the rate of disappearance of AZA-A after greenhouse treatment while tomato epicuticular waxes doubled the photodegradation rate of AZA-A in a commercial formulation.Journal of Environmental Science and Health Part B Pesticides Food Contaminants and Agricultural Wastes 08/2009; 44(6):598-605. · 1.10 Impact Factor -
Article: Flavonoid characterization and antioxidant activity of hydroalcoholic extracts from Achillea ligustica All.
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ABSTRACT: Ethanolic extracts of Achillea ligustica All. (Asteraceae) flowering tops were evaluated. High-performance liquid chromatography-electrospray ionisation-mass spectrometry was used for the identification and quantification of phenolic compounds. 6-Hydroxykaempferol-3,6,4'-trimethyl ether, apigenin-6-C-glucoside-8-C-arabinoside, luteolin, and apigenin were the most abundant flavonoids. For the first time C-glycosylflavones were detected in A. ligustica with apigenin-6-C-glucoside-8-C-arabinoside being the most representative. The radical scavenging activity of the extracts was determined by DPPH test and ranged between 4.18 and 12.3 mM. The ability of these extracts to inhibit non-enzymatic lipid peroxidation was studied using the simple in vitro system of linoleic acid oxidation: five of the nine extracts exerted a protective effect at the lower amount tested (5 microg). Protection on CaCo-2 intestinal cells against TBH-induced toxicity was also investigated: the results showed that two of the extracts tested in this cell system had the ability to protect against oxidative stress induced by TBH starting from concentrations as low as 10 microg/ml.Journal of pharmaceutical and biomedical analysis 07/2009; 50(3):440-8. · 2.45 Impact Factor -
Article: Residue-free wines: fate of some quinone outside inhibitor (QoI) fungicides in the winemaking process.
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ABSTRACT: 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.Journal of Agricultural and Food Chemistry 04/2009; 57(6):2329-33. · 2.82 Impact Factor -
Article: Methyl syringate: a chemical marker of asphodel (Asphodelus microcarpus Salzm. et Viv.) monofloral honey.
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ABSTRACT: During the liquid chromatographic study of the phenolic fraction of monofloral honeys was detected in the asphodel honey ( Asphodelus microcarpus Salzm. et Viv.) chromatogram a distinctive peak not detected in other monofloral honeys such as Arbutus unedo L., Hedysarum coronarium , Eucalyptus spp., and Galactites tomentosa . After thin layer chromatography (TLC) purification and characterization by NMR and LC-MS/MS, the compound was identified as methyl syringate (MSYR) and confirmed against an original standard. Levels of MSYR were measured in honeys of 2005, 2006, and 2007 by HPLC-DAD analysis. Level determination of MSYR was repeated in 2008 for 2006 and 2007 honeys to evaluate chemical stability of this phenolic compound. Levels of MSYR measured 1 year after the sampling did not show significant statistical differences (p < 0.05). The stability of MSYR was also confirmed by 12 asphodel honey samples collected in 2005 that showed amounts of methyl syringate comparable with those found in fresh honey. For the evaluation of MSYR origin, samples of nectars were collected from flowers and the content of MSYR was measured. Levels of MSYR in honeys are originated from the nectar with an average contribution of the nectar to the honey of 80%. Melissopalinological analysis did not allow the attribution of the honey monofloral origin because levels of asphodel pollen were <6% for all analyzed samples. Previously reported levels of MSYR for robinia, rape, chestnut, clover, linden blossom, dandelion, sunflower, thyme, manuka, and fir honeys were <5 mg/kg. For this reason, a minimum level of 122.6 mg/kg for MSYR in asphodel honeys can be considered as a chemical marker and, unlike the melissopalynological analysis, can be used for the origin attribution and to evaluate the percent of asphodel nectar in the honey.Journal of Agricultural and Food Chemistry 04/2009; 57(9):3895-900. · 2.82 Impact Factor -
Article: Persistence of two neem formulations on peach leaves and fruit: effect of the distribution.
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ABSTRACT: Persistence of azadirachtins (A+B) and of the other limonoids (nimbin, salannin, deacetylnimbin, and deacetylsalannin) on peach leaves and fruits was studied using a commercial formulation (form. C) compared with an experimental formulation (form. E) prepared with coformulations allowed in organic culture. Field experiments were carried out using three concentrations: 1x, 5x, and 10x the dose recommended by the manufacturer. The EU maximum residue level (MRL) in fruits and vegetables for azadirachtin A is 1 mg/kg with a preharvest interval (PHI) of 3 days. At the recommended dose, azadirachtin A residue on fruits was not detectable (LOQ < 0.8 microg/kg). After field treatment at the 5x concentration, azadirachtoids were found with 22% in the epicuticular waxes and the remaining 78% on the fruit surface. No residues were found in the fruit pulp. The experimental formulation (E) produced lower residues on leaves and fruit compared with the commercial formulation (C), although formulation E showed greater stability. This is probably due to the amount of the active ingredients that diffuse into the epicuticular wax layer thus enhancing photostability of azadirachtoids.Journal of Agricultural and Food Chemistry 03/2009; 57(6):2457-61. · 2.82 Impact Factor -
Article: Factors affecting the synergy of thiabendazole, sodium bicarbonate, and heat to control postharvest green mold of citrus fruit.
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ABSTRACT: The efficacy of thiabendazole (TBZ) to control postharvest decay caused by Penicillium digitatum of citrus fruit can be enhanced by co-application with sodium bicarbonate (SBC) and/or heat treatment. The impact of these treatments was investigated in citrus fruit, as a function of TBZ and SBC concentration and temperature, and were related to the amount of TBZ residues in fruit (total residues), in fruit surface, in the cuticular wax, and in the inner fruit. The residue levels of TBZ were determined in 'Valencia' oranges following a 1 min dip in an aqueous mixture of SBC at 0.5, 1, or 2 wt %/vol and TBZ at 600 or 400 mg/L (active ingredient, a.i.) at 20 or 40 degrees C and after 0 and 20 days at 17 degrees C and 90% relative humidity. The influence of SBC and heat on the TBZ residue concentration on the fruit surface, in cuticular wax, and on the inner cuticle tissue was determined in 'Salustiana' oranges after a 1 or 3 min dip in TBZ alone at 600 mg/L and 20 or 50 degrees C or for 1 min in TBZ at 600 mg/L and SBC at 2% and 20 degrees C. The efficacy of heat treatments with water, SBC, and TBZ, applied separately or in combination, was investigated on artificially inoculated 'Nova' mandarins and 'Valencia' oranges for the control of postharvest green mold caused by a TBZ-sensitive (TBZ-s) or TBZ-resistant (TBZ-r) isolate of P. digitatum. The residue levels of TBZ in fruit, evaluated as total residues, were not affected by the co-application of SBC in most samples. While TBZ residues in the fruit surface were not significantly affected by the dip temperature or by co-application of SBC, the rates of diffusion and penetration of TBZ into cuticular wax markedly increased in the presence of SBC or when TBZ was applied in combination with heat. TBZ residues in the inner tissue of fruits treated at 20 degrees C were not dependent upon the dip time or by the presence of SBC and were similar to those found in fruit treated with TBZ at 50 degrees C for 1 min, whereas significantly higher values were recorded in samples treated with TBZ at 50 degrees C for 3 min. When TBZ at 600 mg/L and 20 degrees C was applied in the presence of SBC at concentrations of 1-2 or 0.5-2%, it effectively reduced decay caused by the TBZ-resistant isolate of green mold in 'Nova' mandarins and 'Valencia' oranges. This treatment was also significantly more effective than TBZ alone to control green mold caused by a TBZ-s isolate in 'Valencia' oranges. The combination with SBC and mild heat (40 degrees C) and TBZ at 400 mg/L generally improved the control of a TBZ-r isolate of green mold with respect to the combined treatment at 20 degrees C. TBZ efficacy was also improved when applied at reduced rates (200 mg/L) and 50 degrees C, significantly suppressing green mold caused by a TBZ-s isolate of P. digitatum and effectively controlling a TBZ-r isolate. The rate of weight loss of 'Valencia' oranges was significantly increased by SBC treatment and was positively dependent upon the concentration of SBC used in the treatment, while the temperature of the treatment solution had little influence on later weight loss.Journal of Agricultural and Food Chemistry 11/2008; 56(22):10793-8. · 2.82 Impact Factor -
Article: Chemical characterization and DNA tracking of Sardinian botargo by Mugil cephalus from different geographical origins.
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ABSTRACT: The chemical composition of the Sardinian botargo by Mugil cephalus from different geographical origins was investigated. Fat ( approximately 20%), proteins ( approximately 50%), moisture ( approximately 22%), and salt ( approximately 7%) were measured in ground (G) and whole (W) commercial products. Among the nutritional compounds, omega-3 fatty acids were approximately 8%, squalene was approximately 15 mg/100 g, vitamin E was approximately 8.5 mg/kg, and cholesterol was approximately 300 mg/100 g, on average in both products. Antioxidant properties, assessed by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) test and expressed as Trolox equivalent antioxidant capacity (TEAC), showed quite good activity in extracted oil (0.8-1.1 mmol of Tolox/L). Major constituents in the samples varied noticeably, but only few statistical differences were evidenced between G or W products or between samples from different origins. Principal component analysis (PCA) of random amplified polymorphic DNA (RAPD) and proteins, coupled with both, did not differentiate samples from different origins. On the basis of our results, chemical and molecular data exclude the differentiation of samples from diverse origins.Journal of Agricultural and Food Chemistry 11/2008; 56(22):10847-52. · 2.82 Impact Factor -
Article: Liquid chromatography-tandem mass spectrometric ion-switching determination of chlorantraniliprole and flubendiamide in fruits and vegetables.
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ABSTRACT: The anthranilic and phthalic diamides, chlorantraniliprole (CAP) and flubendiamide (FLU), respectively, represent a new class of very effective insecticides that activate the ryanodine-sensitive intracellular calcium release channel (ryanodine receptor). This paper reports an analytical method for the simultaneous determination of the two insecticides on fruits and vegetables by liquid chromatography-electrospray tandem mass spectrometry operated in the positive and negative ionization switching mode. The two diamides were extracted with acetonitrile and separated on a Zorbax Column Eclipse XDB C8 (4.6 mm x 150 mm i.d., 3 microm) by isocratic elution with a mobile phase consisting of acetonitrile and water with 0.1% formic acid pumped at a flow rate of 0.4 mL/min. The diamides were selectively detected by multiple reaction monitoring for transitions of proton adduct precursor ions simultaneously: positive m/z 484.3-->285 for CAP, m/z 445.5-->169 for internal standard, and negative m/z 681.4-->253 for FLU. For CAP calibration in the positive mode was linear over a working range of 2 to 1000 microg/L with r > 0.992. The limit of detection (LOD) and limit of quantification (LOQ) for CAP were 0.8 and 1.6 microg/kg, respectively. For FLU in the negative mode the corresponding values were 1-1000 microg/L for linear working range, with r > 0.996 and 0.4 and 0.8 microg/L for LOD and LOQ, respectively. Moreover, the presence of interfering compounds in the fruit and vegetable extracts was found to be minimal. Due to the linear behavior of the MS detector response for the two analytes, it was concluded that the multiple reaction transitions of molecular ions in the ion-switching mode can be used for analytical purposes, that is, for identification and quantification of diamides in fruit and vegetable extracts at trace levels.Journal of Agricultural and Food Chemistry 09/2008; 56(17):7696-9. · 2.82 Impact Factor -
Article: New experimental data on use of rotenone as an acaricide for control of Varroa destructor in honey bee colonies.
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ABSTRACT: Three slow release experimental rotenone formulations were tested to evaluate their effectiveness against Varroa destructor Anderson & Trueman in colonies with sealed brood and to determine whether they left residues in honey and bees wax: we evaluated cardboard strip containing 1 g rotenone and two types of polyvinyl chloride (PVC) strips containing 1 (high-dose) and 0.5 (low-dose) g of rotenone, respectively. In general, the efficacy of the treatments, expressed as percentage of mite mortality, was highly variable in all treatment groups (range, 0-96.8%). The highest effectiveness was obtained with the high-dose-PVC strips, which caused an average percentage of mortality ranging between 47 and 69% in the adult bees and sealed brood, respectively. At the end of the treatment, rotenone residues ranged between 0.03 and 0.06 and 1.5-144.0 mg/kg in honey and wax, respectively. Rotenone residues in wax were still detectable 4 mo after the treatment period, whereas no residues were found in honey. The higher residues content and persistence recorded in wax samples, was probably due to the lipophilic nature of rotenone. A reduction in the amount of adults was recorded for the group treated with high-dose-PVC strips compared with the untreated colonies. Toxicological risks connected with the use of rotenone and the low maximum level recently fixed by European legislation (0.01 mg/kg) suggest that rotenone is not a good candidate for reducing varroa populations in honey bee colonies.Journal of Economic Entomology 08/2008; 101(4):1075-80. · 1.70 Impact Factor -
Article: A simple and selective method for the measurement of azadirachtin and related azadirachtoid levels in fruits and vegetables using liquid chromatography electrospray ionization tandem mass spectrometry.
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ABSTRACT: Neem-based insecticides containing azadirachtin and related azadirachtoids are widely used in agriculture. Here, we report an analytical method for the rapid and accurate quantification of the insecticide azadirachtin A and B and other azadirachtoids such as salannin, nimbin, and their deacetylated analogues on tomatoes and peaches. Azadirachtoids were extracted from fruits and vegetables with acetonitrile. Using high-performance liquid chromatography/electrospray ionization tandem mass spectrometer, azadirachtoids were selectively detected monitoring the multiple reaction transitions of sodium adduct precursor ions. For azadirachtin A, calibration was linear over a working range of 1-1000 microg/L with r > 0.996. The limit of detection and limit of quantification for azadirachtin A were 0.4 and 0.8 microg/kg, respectively. The presence of interfering compounds in the peach and tomato extracts was evaluated and found to be minimal. Because of the linear behavior, it was concluded that the multiple reaction transitions of sodium adduct ions can be used for analytical purposes, that is, for the identification and quantification of azadirachtin A and B and related azadirachtoids in fruit and vegetable extracts at trace levels.Journal of Agricultural and Food Chemistry 06/2008; 56(9):2939-43. · 2.82 Impact Factor
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Institutions
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2002–2011
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Istituto di Scienze delle Produzioni Alimentari
Bari, Apulia, Italy
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1983–2011
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Università degli studi di Cagliari
- • Department of Medical Science "Mario Aresu"
- • Department of Chemical and Geological Science
Cagliari, Sardinia, Italy
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2010
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Ain Shams University
- Department of Plant Protection
Cairo, Muhafazat al Qahirah, Egypt
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2009
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National Research Council - Italy
Roma, Latium, Italy
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2007
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l' Institut National des Sciences Appliquées et de Technologie (Tunisienne)
Tunis, Gouvernorat de Tunis, Tunisia
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2004
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Università degli Studi di Sassari
Sassari, Sardinia, Italy
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