Seasonal Changes in Chemical Composition of Valeriana Officinalis L. Roots in Natural Conditions and Organic Production System in Latvia

Common valerian (Valeriana officinalis L.) is among top selling medicinal plants in Europe and America due to its calming and sleep-promoting properties. High essential oil and sesquiterpenic acid content is required for high quality produce. This study aims to access quality of valerian roots collected in wild and harvested in organic production system in Latvia in terms of the essential oil composition and content and sesquiterpenic acid. �or the � rst ti me, the quality assessment of wild Valerian grown in Latvia territory has been studied and described.Essential oil was extracted from dried roots by hydro-distillation method. Concentration of essential oil from roots harvested in natural conditions in September and October in 2017 varied from 8.4till 10.7 mL/ kg, from samples harvested in April 2018 varied from 11.5 till 14.2 mL/kg. Essential oil in two-year-old roots of wild populations harvested organic production system in October 2019 varied from 8.46 till 11.3mL/kg. Separation of the biologically active substances was performed by gas chromatography-mass spectrometry, thirty-seven components were identi�ed. The major compounds identi�ed in the oil were bornyl acetate, valerianol, valeranone, intermedeol, camphene, myrtenyl acetate, agarospirol, and γ-eudesmol. Separation of valerenic acids was performed by liquid chromatography.The content of sesquiterpenic acids in Latvian accessions did not exceed 0.02% both in wild and in organic cultivationthus did not reach the threshold of European Pharmacopoeia (0.17 %) thus wild populations of Latvian origin cannot be directly incorporated in commercial growing.