70

SummaryA selective and simplest possible high-performance TLC (HPTLC)

method for quantification of oenothein B on the basis of the free gal-

lic acid and total gallic acid content after acid hydrolysis has been

developed and used for analysis of cultivated Epilobium angustifoli-

um. HPTLC of aqueous extracts of E. angustifolium was performed

on silica gel with benzene–methanol–acetic acid 90:16:8 (v/v), as

mobile phase. Quantitative evaluation of the plate was performed at

570 nm after derivatization with 1% ethanolic FeCl3

solution. The

method was validated for precision, repeatability, and accuracy.

Average recovery of the active ingredient from the samples was in

the range 95.43–104.57%. The calibration plots were linear in the

range 440–2200 ng per band. The technique was used, for the first

time, for estimation of the oenothein B content of cultivated

E. angustifolium. The oenothein B content was highest at budding

time (18.4–20.2 mg g–1) and decreased dramatically to 1.0 mg g–1

after flowering.

1 Introduction

The genus Epilobium (Onagraceae) consists of over 200 species

of willow-herbs found all over the world. Approximately sixty

Epilobium species have been described in Russia, the most com-

mon being Epilobium angustifolium L. syn. Chamaenerion

angustifolium L. E. angustifolium is widely used in traditional

and officinal medicine in different countries for benign prostate

hyperplasia and associated problems of micturition [1–3]. The

dried aerial parts are used in infusions and consumption of these

herbal teas is very common, because of the high prevalence of

this disease in the population [4, 5]. It has been shown that aque-

ous extracts of the aerial parts of E. angustifolium have anal-

gesic, antioxidant, anti-inflammatory activity, and antitumor and

antiandrogenic effects [6–9].

The herb is rich in polyphenolic compounds [10, 11], phenolic

acids [12] and ellagitannins [13].

Oenothein B (Figure 1) was first reported, by Okuda, as a

dimeric hydrolyzable ellagitannin from an extract of Lythrum

A.N. Shikov, O.N. Pozharitskaya, S.A. Ivanova, and V.G. Makarov, Saint Peters-burg Institute of Pharmacy, 47/5, Piskarevskiy pr., 195067, St. Petersburg, Russia,Interregional Fund “Adaptation”, 1, Ushakova, 188800, Vyborg, Russia;V.P. Tikhonov, “Diod” Ltd, 11a Derbenevskaya Ave., 113114, Moscow, Russia;and B. Galambosi, MTT Agrifood Research Finland, Plant Production Research,Karilantie 2 A, 50600 Mikkeli, Finland.E-mail: alexs79@mail.ru

Improved and Validated HPTLC Method for Quantificationof Oenothein B and its Use for Analysis of Epilobiumangustifolium L.

Alexander N. Shikov*, Olga N. Pozharitskaya, Svetlana A. Ivanova, Valery G. Makarov, Vladimir P. Tikhonov, and Bertalan Galambosi

Key Words

Epilobium angustifoliumHPTLCOenothein BValidation

Figure 1

The chemical structure of oenothein B.

Journal of Planar Chromatography 23 (2010) 1, 70–74 DOI: 10.1556/JPC.23.2010.1.120933-4173/$ 20.00 © Akadémiai Kiadó, Budapest