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A study of the effects of cultivation variety, collection time, and climate on the amount of oleuropein in olive leaves

100%

Hashemi P. , Delfan B. , Ghiasvand A. R. , Alborzi M. , Raeisi F.

tom Vol. 22, no. 1

133--140

Effects of cultivation variety, collection time, and climate on amounts of oleuropein (OE), a strong antioxidant, in olive leaves were studied. A modified ultrasound-assisted method was used for efficient and quantitative extraction of OE from olive leaf samples before their analysis by a rapid HPLC method. Under the optimized conditions, the extraction was performed in two successive steps with an RSD better than 2.95% ( n = 5) and a detection limit of 0.02 μg OE. The amount of OE was determined in twelve samples of olive leaves from Mary Zeitoon, Koroneiki , and Sevillana varieties cultivated in three different regions of Iran after collection in two different seasons. The results confirmed that the amounts of OE varied in different olive varieties with mean values of 127, 115, and 144 μg g -1, respectively, although statistical tests indicated a significant interaction of collection time and climate with olive variety. In general, the OE concentration was significantly higher in the cold season and in the tropical regions than in the hot season and the temperate region.

Development of ultrasound-assisted extraction followed by solid-phase extraction followed by dispersive liquid–liquid microextraction followed by gas chromatography for the sensitive determination of diazinon in garden parsley as vegetable samples

88%

Rezaee M. , Khalilian F. , Pourjavid M. R.

Acta Chromatographica

2023

tom Vol. 35, no. 4

347--353

A new pretreatment method termed ultrasound-assisted extraction (UAE) which is combined with solid-phase extraction which is combined with dispersive liquid-liquid microextraction (SPE-DLLME) followed by gas chromatography-flame ionization detector (GC-FID) analysis has been developed for the determination of diazinon in garden parsley as vegetable samples. The analyte was extracted from garden parsley sample using ultrasound-assisted extraction followed by solid-phase extraction followed by dispersive liquid-liquid microextraction. Various parameters that affect the efficiency of the extraction techniques have been optimized. The calibration plot was linear in the range of 5.0–1,000 μg kg⁻¹ with detection limit of 1.0 μg kg⁻¹ for diazinon in garden parsley samples. The results confirm the suitability of the UAE-SPE-DLLME-GC-FID as a sensitive method for the analysis of the targeted analyte in garden parsley samples.

Ultrasound-assisted acetic acid extraction of metals from soils

51%

Krasnodębska-Ostręga B. , Kowalska J.

Chemia Analityczna

2003

tom Vol. 48, No. 6

967-974

In order to assess metal availability from soils to ecosystem the 16-h single extraction with 0.43 mol L(-1) CH(3)COOH (BCR) is being commonly applied. To shorten the extraction time of Cd, Pb and Zn from soil samples sonication has been'additionally applied. The influence of sonication time and temperature on the extraction efficiency has been studied. One compared the results obtained in both extraction procedures: ultrasonic and conventional BCR. The contents of Cd, Pb and Zn in soil extracts were determined by stripping voltammetry on hanging mercury drop electrode. ICP MS was used as a reference technique.

16-godzinna ekstrakcja za pomocąO,43 mol L(-1) roztworu CH(3)COOH (procedura BCR) jest powszechnie wykorzystywana do określania dostępności metali z gleb do ekosystemu. W celu skrócenia czasu ekstrakcji Cd, Pb i Zn z gleb zastosowano ekstrakcję wspomaganą ultradźwiękami. Zoptymalizowano czas sonifikacji i temperaturę ekstrakcji. Porównano wydajności ekstrakcji wspomaganej ultradźwiękami z ekstrakcją przeprowadzoną według procedury BCR. Do oznaczeń zawartości Cd, Pb i Zn w ekstraktach zastosowano woltamperometrię ze wstępnym zatężaniem na wiszącej kroplowej elektrodzie rtęciowej oraz ICP-MS jako metodę porównawczą.