Essential Oil Constituents of Seeds of Two Monodora Species from Nigeria

The genus Monodora (Annonaceae) comprises many aromatic and economically important species, widely distributed across tropical Africa. They are sources of edible fruits, spices and medicines. Monodora myristica and M. tenuifolia are the prominent species in Southwest Nigeria. The fruit seeds of M. myristica are locally sold and generally used as spices and condiments in cuisines or as snuff flavour.

Differences exist largely in the oil content and composition of M. myristica seeds due to different processing techniques and handling, which could affect its quality. The study aimed at profiling the volatile oils of freshly collected seed for quality control. Seeds of mature ripe and unripe fruits of M. myristica and mature ripe fruits of M. tenuifolia were pulverised and subjected to hydrodistillation to extract the volatile oils. The oils were analysed using gas chromatography-mass spectrometry. The compounds were identified by their Kovats indices and comparison with literature values.

Both unripe and ripe seed oils of M. myristica consisted mainly of monoterpene hydrocarbons, with α-phellandrene as the major constituent, 74.60% and 70.86%, respectively. The seed oil of M. tenuifolia had mainly sesquiterpenes, with germacrene-D (24.43%) as the major constituent. The presence of the psychoactive compound, myristicin was highest in M. tenuifolia seed oil (1.88%) compared to M. myristica unripe (0.14%) and ripe (0.27%) seed oils.

The differences in composition observed are useful for quality control purposes and the implication of the myristicin content of the oils should be discussed.

Publication History

Article published online:
16 November 2023