Epilobium angustifolium L.(Oenotheraceae), a representant of willow-herbs species found throughout northern
temperate regions, is used in folk medicine for benign prostate hyperplasia (PBH)
and associated with problems of micturition. Its use to treat prostatic adenoma has
also been mentioned. The dimeric ellagitannin oenothein B (OeB) appeared to be responsible
for some observed biological activity of extracts [1,2,3]. Flavonoids possibly act
synergistically with oenothein B [3,4,5].
The method of separation and quantitative determination of OeB and quercetin glucuronide
(GQ) in an aqueous extract of Epilobii angustifolii herba by HPTLC-densitometry was
developed. Powdered plant material was extracted with water (1:10) in an ultrasonic
water bath. The extract was filtrated and lyophilised. Samples were applied by an
automatic applicator. Chromatography was performed in a vertical chamber. HPTLC RP-18
WF254 plates were used. As a first mobile phase 25% of MeCN in water (+ 50mM H3PO4) was used (distance of 8cm), then acetonitrile was used as a second mobile phase
(distance of 4cm). Plates were dried and scanned. Densitometry was carried out by
using of Shimadzu CS-9301PC densitometer. The absorption spectra were recorded at
270nm (OeB) after first developing and at 350nm (GQ) after second. The amount of OeB
and GQ in the aqueous extract of Epilobii angustifolii herb using the developed method
were 152.46±4.92mg g-1 and 22.07±1.38mg g-1respectively.
References: [1] Hiermann A., Radl B. (1998) J Chromatogr A 803: 311. [2] Vitalone A. et al. (2003)
Pharmacol 69: 79. [3] Kiss A. et al. (2006) Pharmazie 61: 66. [4] Shikov A.N. et al.
(2006) J Agric Food Chem 54: 3617. [5] Kiss A. et al. (2004) Planta Med. 70: 919.
