4 research outputs found
Quantitative Screening of Agrochemical Residues in Fruits and Vegetables by Buffered Ethyl Acetate Extraction and LC-MS/MS Analysis
A buffered
ethyl acetate extraction method is proposed for the
simultaneous analysis of 296 agrochemicals in a wide range of fruit
and vegetable matrices by liquid chromatography–tandem mass
spectrometry (LC-MS/MS). The optimized quantity of acetate buffer
(1% acetic acid + 0.5 g of sodium acetate per 10 g of sample) adjusted
the pH of each test matrix to 5–6, which in turn significantly
improved recoveries of acidic and basic compounds. The role of diethylene
glycol (used in the evaporation step) on signal suppression of certain
compounds was evaluated, and its quantity was optimized to minimize
such an effect. The method was validated in grape, mango, drumstick,
bitter gourd, capsicum, curry leaf, and okra as per the DG-SANCO/12571/2013
guidelines. Recoveries in the fortification range of 1–40 μg/kg
were within 70–120% with associated relative standard deviations
below 20% for most of the compounds. The method has potential for
regulatory and commercial applications with a generic approach
Quantitative Screening of Agrochemical Residues in Fruits and Vegetables by Buffered Ethyl Acetate Extraction and LC-MS/MS Analysis
A buffered
ethyl acetate extraction method is proposed for the
simultaneous analysis of 296 agrochemicals in a wide range of fruit
and vegetable matrices by liquid chromatography–tandem mass
spectrometry (LC-MS/MS). The optimized quantity of acetate buffer
(1% acetic acid + 0.5 g of sodium acetate per 10 g of sample) adjusted
the pH of each test matrix to 5–6, which in turn significantly
improved recoveries of acidic and basic compounds. The role of diethylene
glycol (used in the evaporation step) on signal suppression of certain
compounds was evaluated, and its quantity was optimized to minimize
such an effect. The method was validated in grape, mango, drumstick,
bitter gourd, capsicum, curry leaf, and okra as per the DG-SANCO/12571/2013
guidelines. Recoveries in the fortification range of 1–40 μg/kg
were within 70–120% with associated relative standard deviations
below 20% for most of the compounds. The method has potential for
regulatory and commercial applications with a generic approach
Validation of a Residue Analysis Method for Streptomycin and Tetracycline and Their Food Safety Evaluation in Pomegranate (<i>Punica granatum L.</i>)
A single-step methanol extraction
based method was developed and
validated for simultaneous estimation of the residues of streptomycin
and tetracycline group compounds in pomegranate fruits by LC–MS/MS.
The limits of quantification for all target compounds were ≤0.005
mg kg<sup>–1</sup> with recoveries (%) at fortification levels
of 0.005, 0.01, and 0.05 mg kg<sup>–1</sup> being within 90–116%
(RSD ≤ 9%) and interday precision RSD ≤ 12% at 0.01
mg kg<sup>–1</sup>. A field experiment on the dissipation of
streptomycin and tetracycline (including 4-epimers) residues in pomegranate
fruits with regards to field applications of the commercial formulation
Streptocycline SP (streptomycin sulfate 90% + tetracycline hydrochloride
10%) at 200 and 400 g a.i. ha<sup>–1</sup> indicated preharvest
intervals of 45 and 55 days for streptomycin and 12 and 15 days for
tetracycline, respectively. The study will be useful in promoting
effective residue monitoring and ensuring safe use of these antibiotics
in managing bacterial diseases of pomegranate
Comparison of organic and conventional farming for onion yield, biochemical quality, soil organic carbon, and microbial population
<p>In an ongoing field experiment, organic and conventional farming (control) were compared for onion bulb yield, biochemical quality, soil organic carbon (SOC), and microbial activity after the sixth cropping cycle. The treatments used for organic production were farmyard manure (FYM, 20,000 kg ha<sup>−1</sup>), poultry manure (PM, 10,000 kg ha<sup>−1</sup>), vermicompost (VC, 10,000 kg ha<sup>−1</sup>), neem cake (NC, 5000 kg ha<sup>−1</sup>), and a combination of FYM (5000 kg ha<sup>−1</sup>), PM (2500 kg ha<sup>−1</sup>), VC (2500 kg ha<sup>−1</sup>), and NC (1250 kg ha<sup>−1</sup>); all treatments were compared with the control. Organic treatments produced 24.6–43.6% lower yield consistently for 6 years than the control treatment. No significant difference was observed between PM, FYM, and VC treatments for the bulb yield. Bulb analysis during the sixth year indicated that plants that received FYM, PM, or VC had higher levels of total phenol, total flavonoid, ascorbic acid, and quercetin-3-glucoside than the control plants. All the five organically treated sets had significantly higher values of SOC, microbial population, fungal-to-bacterial ratio, and dehydrogenase activity than the control and the initial values in each treated set. The results indicate that FYM, PM, or VC application enhances biochemical quality and organic farming is more sustainable than conventional farming.</p