Variation of Main Alkaloids and Fatty Acids among Five Natural Populations of Peganum harmala L. from Iran

Alkaloids and fatty acids extracted from plant species are considered as popular ingredients in pharmaceutical products. The medicinal herb Peganum harmala L., native to arid and semi-arid rangeland, is known as an excellent source of β-carboline alkaloids and some important essential fatty acids. In order to extend the knowledge of phytochemical biodiversity of P. harmala, main alkaloids and fatty acids contents of the populations collected from five different parts of Iran were investigated. Harmine and harmaline, that are the main β-carboline alkaloids of P. harmala seed extract, were identified by FTIR and quantified by HPLC. Significant quantitative differences (p ≤ 0.01) were observed in harmaline (295-354.16 mg/g dry extract) and harmine (257.91-304.66 mg/g dry extract) contents among studied populations. Furthermore, seed oil was extracted and analysis of fatty acids was performed quantitatively using GC method. The result showed that the average oil content of P. harmala was 15.82±1.06%, with no significant difference (p ≤ 0.05) among the samples. The most abundant fatty acid in all analyzed samples was linoleic acid (C18:2) (54.33-60.53% of the total fatty acids). Statistical analysis revealed significant differences (p ≤ 0.05) among the populations for linoleic acid (C18:2) (58.21±2.70%) and palmitic acid (C16:0) (9.99±1.19%) contents. Additionally, all the samples were rich in unsaturated fatty acids and β-carbolines, harmaline and harmine. These data indicate that the amounts of major alkaloids and fatty acids vary considerably among the P. harmala’s natural populations, which could be potential sources of these important phytochemicals for pharmaceutical and industrial purposes.