Variation in essential oil components among Iranian Ferula assa-foetida L. accessions

Abstract

Abstract Oleo gum resin is extracted from the Ferula assa-foetida L. and is important for pharmacological and industrial applications. In the present study, the essential oil components of fourteen Iranian and Afghan F. assa-foetida accessions were analyzed. A total of 20\u202fg of the oleo gum resins were hydro-distilled in a Clevenger type apparatus for 3\u202fh in three replications. The amounts of essential oil yield ranged from 2.53 to 20.85%, indicating a high level of variation in this feature among the accessions. The results of GC–MS analysis discovered 42 compounds in the accessions. Six of these compounds were found most abundantly in the samples. These were (E)-1-propenyl sec-butyl disulfide (13.66–49.35%), β-pinene (1.06–21.18%), (Z)-1-propenyl sec-butyl disulfide (2.02–15.29%), α-pinene (2.04–17.61%), thiophene (0.03–36.81%), and thiourea (0.08–9.63%). Based on cluster analysis, four chemotypes were introduced among the F. assa-foetida accessions. The results indicated that as the altitude increased, the amount of β-pinene increased too, whereas the amounts of (Z)-1-propenyl sec-butyl disulfide and thiourea decreased. In addition, the t-test and the correlation analysis revealed that altitude was the most effective environmental factor which explained the high levels of variation in the essential oil yield and components.