Acta Pharm. 66 (2016) 543-554

 

full paper

Short communication

 

TLC determination of flavonoids from different cultivars of Allium cepa and Allium ascalonicum

LORETTA POBŁOCKA-OLECH, DANIEL GŁÓD, MARIA E. ŻEBROWSKA, MAŁGORZATA SZNITOWSKA and MIROSLAWA KRAUZE-BARANOWSKA

krauze@gumed.gda.pl

1 Department of Pharmacognosy with Medicinal Plants Garden

2 Department of Pharmaceutical Technology; Faculty of Pharmacy with Subfaculty of Laboratory Medicine, Medical University of Gdańsk, 80-416 Gdańsk, Poland

Accepted April 20, 2016

Published online September 6, 2016

 

This study comprises the optimization and validation of a new TLC method for determination of flavonols in the bulbs of seven cultivars of onions and shallots. Separation was performed on RP-18 plates with the solvent mixture tetrahydrofuran/water/formic acid (40+60+6, V/V/V) as a mobile phase. The method was validated for precision, linearity, LOD, LOQ, accuracy and robustness. Chromatographic analysis of the extracts revealed the presence of three main flavonols, quercetin, quercetin-4’-O-glucoside and quercetin-3,4’-O-diglucoside in the majority of analyzed cultivars. The content of flavonols in the analyzed extracts of onion bulbs varied from 123 (‘Exihibition’) to 1079 mg kg–1 fresh mass (fm) (‘Hybing’) in edible parts, and from 1727 (‘Hyline’) to 28949 mg kg–1 fm (‘Red Baron’) in outer scales. The bulbs of two shallot cultivars contained 209 (‘Ambition’) and 523 mg kg–1 fm (‘Matador’) of flavonols in edible parts and 5426 and 8916 mg kg–1 fm in outer scales, respectively.

 

Keywords: Allium cepa, Allium ascalonicum, cultivar varieties, flavonols, TLC, quantitative analysis