Abstract:
Essential oils are sensitive and complex mixtures which
are composed of volatile secondary metabolites. The
chemical profile of essential oils harvested from a
particular plant vary with different parameters such as
climate, soil type, methods of extraction, geographical
origin, plant part and harvest conditions. As such, it is of
paramount necessity to profile the essential oils extracted
under different conditions as this can determine their
potential applications. This study explored for the first
time, the chemical composition of Croton gratissimus
essential oil extracted by hydrodistillation from fresh
leaves harvested on different dates. There was no
difference in the essential oil yields obtained from the
leaves harvested on different dates. The chemical
profiling using gas chromatography mass spectrometry
showed that the most dominant component in the
essential oils extracted from the leaves harvested on
different dates was cis-muurola-4(15),5-diene although
its percentage abundance varied significantly. The
essential oil extracted from the leaves harvested on
different days also showed significant variation in the
percentage composition of other major compounds such
as camphor, germacrene D, β-himachalene,
caryophyllene, α-muurolol and aromadendrene. The
most abundant class of secondary metabolites for the
essential oils harvested on all dates studied was the
sesquiterpenes which also varied significantly in its
percentage composition. These results point to a
significant variation in the chemical profile of essential
oils harvested from the same plant on different dates.
Consequently, it is important to determine the chemical
profile of the leaves of Croton gratissimus as it can vary
depending on the conditions.