Quality control of valerian products by HPLC fingerprint analysis

Valerian roots are used to relief temporary mild nerve tensions and/or difficulties in falling asleep [1]. Hendriks and colleagues implicated valerenic acid, isolated from valerian root, as it produced barbiturate-like effects on performance tests with mice [1,2]. According to another report, neither the extract nor the compounds had shown considerable sedative effects [3]. However crude extracts of valerian roots are sold as herbal medicinal product (HMP) or dietary supplement in the form of capsules. In terms of quality control, it is important to know the chemical compounds present in a crude drug. In this study, modified European Pharmacopoeia HPLC method was used for fingerprint analysis of roots from cultured Valeriana officinalis L. (Valerianaceae) and valerian commercial products. Test solution for HPLC was prepared with methanol. Valerenic acid and acetoxy valerenic acid were used as reference substances. According to the European Pharmacopoeia, the amount of sesquiterpenic acids, expressed as valerenic acid, should be at least 0.17% w/w [4]. In our study, we analyzed total 18 HMP and dietary supplement samples by HPLC and the results showed remarkable variations of the valerian commercial products. Highest amounts of valerenic acids were detected in VO-2 (0.14%), trace amounts in VO-4 (0.05%), and none in the VO-5. Hydroxyvalerenic acid was increased when valerian products were stored longer than shelf life.

Acknowledgements: This study was supported by grants from Hacettepe University Scientific Research Projects (Project No: THD-2016 – 9171).

Keywords: Quality control, HPLC, Valeriana officinalis.

References:

[1] EMA/152385/2016 Valerian root, Valeriana officinalis L. radix, Available at ”http://www.ema.europa.eu/docs/en_GB/document_library/Herbal_-_Summary_of_assessment_report_for_the_public/2016/04/WC500205467.pdf”

[2] Houghton PJ. The scientific basis for the reputed activity of Valerian. J Pharm Pharmacol 1999; 51: 505 – 512

[3] Hendriks H, Bos R, Woerdenbag HJ, Koster S. Central nervous depressant activity of valerenic acid in the mouse. Planta Med 1985; 1: 28 – 31

[4] The European Pharmacopoeia, 8^th ed., Council of Europe, Strasbourg, 2015; 2: 1413.