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

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

Acta Chromatographica

2010

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.

Simultaneous homogeneous liquid-liquid extraction of Ni(II) and Cu(II) using new vic-dioxime derivative

Ghiasvand A. R., Shadabi S., Kakanejadifard A.

Chemia Analityczna

2007

Vol. 52, No. 1

125-133

A new vic-dioxime derivative (2H-1,4-benzolhioazine-2.3(4H)dionedioxime, Oxime I) has been synthesized and investigated as a selective compiexing ligand for homogeneous liquid-liquid extraction and preconcentration of Ni2+ and Cu!2+ ions. Zony l FSA has beenapplied as a phase separation agent. The influence of pH. type, and concentration of water-miscible organic solvent, Zonyl FSA, and Oxime I, as well as the effect of different diverse ions on extraction and determination of Ni2+ and Cu22+ ions has been investigated. Under optimum conditions ([Oxime l]T = 1.2 x 10 mol L-1, [THF]T = 16.7 % v/v, [FSA]T = 3.2 % m/v, pH = 4.5), 5 ng of each Ni2+ and Cu2+ in 5.5 mL aqueous phase was extracted quantitatively into 75 &muL of the precipitated liquid phase. Limit of detection of the proposed method was 0.004 ng mL-1 for Ni2+ and 0.005 ng mL-1for Cu2+. The proposed method has been extended over extraction and determination of Ni:2+ and Cu2+ ions in different synthetic and natural water samples.

Zsyntetyzowano nową pochodną (2H-1,4-benzotiazyno-2,3(4H)dionodioksymu. oksyrn I) i badanoją pod kątem zastosowania jako kompeksującego ligandu do jednorodnej ekstrakcji ciecz-ciecz i wstępnego zateżania jonów Ni2+ i Cu2+. Jako czynnika rodzielającego fazy użyto Zonylu FSA. Badano wpływ pH oraz wpływ rodzaju i stężenia mieszającego się z wodą rozpuszczalnika organicznego. Zonylu FSA i oksymu I, a także wpływ rozmaitych jonów na ekstrakcje i oznacznie Ni2+ i Cu2+t. W optymalnych warunkach ([oksyrn I]T = 12 x 10-3 moL L-1, [THF]T = 16,7 % v/v, [FSA]T = 3.2 % v/v, pH = 4.5), 5 ng Ni2+ i Cu2+ w 5,5 mL-1 fazy wodnej wyekstrahowano do 75 &.L strąconej fazy ciekłej. Granica wykrywalności proponowanej metody wynosi 0.004 ng mL-1 w przypadku Ni2+ i 0,005 ng mL-1 w przypadku Cu2+. Metodę zastosowano do ekstrakcji i oznaczania Ni2+ i Cu+2 w syntetycznych i naturalnych próbkach wód.