Original article
Essential oil from Artemisia herba-alba Asso grown wild in Algeria: Variability assessment and comparison with an updated literature survey
- Open Access funded by King Saud University
- Under a Creative Commons license
Abstract
The chemical variability of the essential oils of Artemisia herba-alba Asso aerial parts, collected at Algeria was evaluated. A. herba-alba populations were collected in four regions, Benifouda; Bougaa; Boussaada and Boutaleb, at two different periods, July (flowering phase), and October and November (vegetative phase). The essential oils were isolated by hydrodistillation and analyzed by Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC-MS). The essential oils yield ranged between 0.2% and 0.9% (v/d.w.). Fifty components were identified in A. herba-alba oils, oxygen-containing monoterpenes being dominant in all cases (72–80%). Camphor (17–33%), α-thujone (7–28%) and chrysanthenone (4–19%) were the major oil components. Despite the similarity in main components, three types of oils could be defined, (a) α-thujone : camphor (23–28:17–28%), (b) camphor : chrysanthenone (33:12%) and (c) α-thujone : camphor : chrysanthenone (24:19:19%). The comparison between the present data and an updated survey of the existing literature reinforces the major variability of A. herba-alba essential oils and stresses the importance of obtaining a defined chemical type crop production avoiding the wild harvest.
Keywords
- Asteraceae;
- Artemisia herba-alba Asso;
- Essential oil;
- Chemical variability;
- Algeria
1. Introduction
Asteraceae Martinov (= Compositae Giseke) is a family of herbs, shrubs or trees, commonly known as Aster or Compositae family, comprising about 1535 genera and 23,000 species. Artemisia (wormwood, tarragon), one of the most economically important and widespread of this family genus, includes 400 species ( Judd et al., 2002).
Dobignard, (1977) has shown the taxonomic complexity of A. herba-alba lato sensu described in North Africa, and the need for a taxonomic study of the whole group. In the present study we followed the traditional criterion of this species delimitation. Eleven spontaneous Artemisia species are present in the Algerian flora ( Quezel and Santa 1963). Artemisia herba-alba Asso = [Artemisia aragonensis Lam.,Seriphidium herba-alba (Asso) Soják] ( Greuter, 2006–2009), commonly known as white wormwood or desert wormwood (Arabic name chih), is a greyish-strongly aromatic dwarf shrub native to the South western Europe, Northern Africa, Arabian Peninsula and Western Asia.
The economic value, the local medicinal uses, the disappearance in some areas due to pasture and over-collection, as well as the potential use to restore degraded ecosystems support the large number of studies on A. herba-alba. A recent review detailed the distribution, taxonomy, morphology, phytochemistry and biological activities of A. herba-alba and its different extracts ( Mohamed et al., 2010).
Among A. herba-alba phytochemical constituents, essential oils have been extensively studied, with several chemotypes being recognized. The variability from the essential oils isolated from A. herba-albacollected at Algeria, Israel, Morocco and Spain was revised by Dob and Benabdelkader in 2006, but, since then, many other studies reinforced its high chemical polymorphism ( Table 1, and references therein). Plants were collected from wild in different countries, grown under controlled experimental field conditions, collected at different harvesting times, subject to different drying periods and processes, extracted fresh or dry, by hydrodistillation or steam-distillation under different experimental conditions, and different aerial plant parts have been used ( Table 1).
