LC-MS/MS Tandem Mass Spectrometry for Analysis of Phenolic Compounds and Pentacyclic Triterpenes in Antifungal Extracts of Terminalia brownii (Fresen)

Decoctions, macerations and fumigations of the stem bark and wood of Terminalia brownii Fresen. are used in traditional medicine for fungal infections and as pesticides on field crops and in traditional granaries in Sudan. In addition, T. brownii is commonly used for protecting wooden houses and furniture. Therefore, using agar disc diffusion and macrodilution methods, eight extracts of various polarities from the stem wood and bark were screened for their growth inhibitory effects against filamentous fungi commonly causing fruit, vegetable and grain decay, as well as infections in the immunocompromised host. Ethyl acetate extracts of the stem wood and bark gave the best antifungal activities, with MIC values of 250 µg/ml against Nattrassia mangiferae and Fusarium verticillioides, and 500 µg/ml against Aspergillus niger and Aspergillus flavus. Aqueous extracts gave almost as potent effects as the ethyl acetate extracts against the Aspergillus and Fusarium strains, and were slightly more active than the ethyl acetate extracts against Nattrassia mangiferae. Thin layer chromatography, RP-HPLC-DAD and tandem mass spectrometry (LC-MS/MS), were employed to identify the chemical constituents in the ethyl acetate fractions of the stem bark and wood. The stem bark and wood were found to have a similar qualitative composition of polyphenols and triterpenoids, but differed quantitatively from each other. The stilbene derivatives, cis- (3) and trans- (4) resveratrol-3-O-β-galloylglucoside, were identified for the first time in T. brownii. Moreover, methyl-(S)-flavogallonate (5), quercetin-7-β-O-di-glucoside (8), quercetin-7-O-galloyl-glucoside (10), naringenin-4`-methoxy-7-pyranoside (7), 5,6-dihydroxy-3`,4`,7-tri-methoxy flavone (12), gallagic acid dilactone (terminalin) (6), a corilagin derivative (9) and two oleanane type triterpenoids (1) and (2) were characterized. Our results justify the traditional uses of macerations and decoctions of T. brownii stem wood and bark for crop and wood protection and demonstrate that standardized extracts could have uses for the eco-friendly control of plant pathogenic fungi in African agroforestry systems. Likewise, our results justify the traditional uses of these preparations for the treatment of skin infections caused by filamentous fungi.

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Multiresidue Analysis of Pesticides in Moringa Pods by GC-MS/MS and LC-MS/MS

Journal of AOAC International ◽

10.1093/jaoacint/qsaa053 ◽

2020 ◽

Vol 103 (6) ◽

pp. 1486-1497

Author(s):

Anirban Dutta ◽

Sandip Hingmire ◽

Kaushik Banerjee

Keyword(s):

Mass Spectrometry ◽

Tandem Mass Spectrometry ◽

Ethyl Acetate ◽

Large Scale ◽

Tandem Mass ◽

Multiresidue Analysis ◽

Method Performance ◽

Chromatography Tandem Mass Spectrometry ◽

Ms Analysis ◽

Accuracy And Precision

Abstract Background Moringa pods are known for their nutritional and health benefits. The cultivation of this crop receives frequent pesticide applications. In the absence of risk assessment data, maximum residue limits of pesticides in this crop are considered at the default level (0.01 mg/kg). However, there exists scarcely any validated method for pesticide residue analysis in this matrix. Objective This study was undertaken to develop and validate a multiresidue method for the simultaneous analysis of multi-class pesticides in moringa pods by gas chromatography-tandem mass spectrometry (GC-MS/MS), and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Method The homogenized sample (10 g) was extracted with acetonitrile (10 mL). The extract was cleaned by dispersive solid-phase extraction using a combination of 50 mg primary secondary amine, 5 mg graphitized carbon black, and 25 mg C18 sorbents, and was directly analyzed by LC-MS/MS. Another portion of the extract was reconstituted in ethyl acetate before GC-MS/MS analysis. The method was validated as per the SANTE/12682/2019 guidelines using GC-MS/MS (180 pesticides) and LC-MS/MS instruments (203 pesticides). Results The method provided a satisfactory analysis of the targeted pesticides with good calibration linearity (r2>0.99), high precision (RSD < 20%), and accuracy (recoveries, 70 to 120%). The reconstitution of the acetonitrile extract in ethyl acetate significantly reduced the matrix effects on GC-MS/MS analysis. The use of matrix-matched standards could correct all recoveries. Conclusions The method offered a large-scale analysis of multi-class pesticides with high accuracy, and precision at 10 ng/g, and higher levels. The method performance complied with the regulatory requirements, and thus, can be implemented in routine testing purposes. Highlights The study reports a validated method for large-scale multiresidue analysis of pesticides in moringa matrix for the first time. The method provided a high throughput analysis of multi-class pesticides with satisfactory selectivity, sensitivity, accuracy, and precision.

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Analysis of Veterinary Drug and Pesticide Residues Using the Ethyl Acetate Multiclass/Multiresidue Method in Milk by Liquid Chromatography-Tandem Mass Spectrometry

Journal of Analytical Methods in Chemistry ◽

10.1155/2016/2170165 ◽

2016 ◽

Vol 2016 ◽

pp. 1-17 ◽

Cited By ~ 7

Author(s):

Husniye Imamoglu ◽

Elmas Oktem Olgun

Keyword(s):

Mass Spectrometry ◽

Acetic Acid ◽

Liquid Chromatography ◽

Tandem Mass Spectrometry ◽

Ethyl Acetate ◽

Pesticide Residues ◽

Simple Procedure ◽

Veterinary Drug ◽

Tandem Mass ◽

Multiresidue Method

A rapid and simple multiclass, ethyl acetate (EtOAc) multiresidue method based on liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) detection was developed for the determination and quantification of 26 veterinary drugs and 187 total pesticide residues in milk. Sample preparation was a simple procedure based on liquid–liquid extraction with ethyl acetate containing 0.1% acetic acid, followed by centrifugation and evaporation of the supernatant. The residue was dissolved in ethyl acetate with 0.1% acetic acid and centrifuged prior to LC-MS/MS analysis. Chromatographic separation of analytes was performed on an Inertsil X-Terra C18 column with acetic acid in methanol and water gradient. The repeatability and reproducibility were in the range of 2 to 13% and 6 to 16%, respectively. The average recoveries ranged from 75 to 120% with the RSD (n=18). The developed method was validated according to the criteria set in Commission Decision 2002/657/EC and SANTE/11945/2015. The validated methodology represents a fast and cheap alternative for the simultaneous analysis of veterinary drug and pesticide residues which can be easily extended to other compounds and matrices.

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