Organizing co mmittee

COMPONENT COMPOSITION OF ESSENTIAL OIL Senecio 
subdentatus FLORA OF UZBEKISTAN 
 
B.S. Okhundedaev, Kh.М. Bobakulov, Sh.R. Makhmudova, S.Z. Nishanbaev 
 
S.Yu. Yunusov Institute of the Chemistry of Plant Substances Academy of sciences of the 
Republic of Uzbekistan st. Mirzo-Ulugbek, 77, 100170 Tashkent 
e-mail: [e-mail] 
 
The genus 
Senecio
belonging to the tribe 
Senecioneae
of the family 
Asteraceae
(Compositae) is the largest genus and includes more than 1500 species of aromatic herbs and 
shrubs widely distributed throughout the world [1-2]. Several herbaceous species of the genus 
are grown as ornamental plants. In the flora of Central Asia, plants of the genus 
Senecio
are 
represented by twenty-three species, ten of which grow in Uzbekistan, with the most common 
being 
S. subdentatus
(Bunge) Ledeb. In chemical terms, this plant is practically little studied, 
it is only noted that flavonoids quercetin, isorhamnetin and their glycosides were found from 
the aerial part of the plant [3]. The chemical composition of the essential oil of 
S. subdentatus
has not been previously studied. 
The aim of this work was to study the chemical composition of the aerial part of 
S. 
subdentatus
of the flora of Uzbekistan. 
The aerial part of 
S. subdentatus
was collected during the flowering period in the 
Kyzylkum deserts, along the Khiva-Bukhara road in the Bukhara region of the Republic 
of Uzbekistan in early May 2022. 
The essential oil from the finely chopped aerial part of 
S. subdentatus
was obtained 
by hydrodistillation for 3-4 hours. The resulting essential oil of 
S. subdentatus
was a 
pale yellow mobile liquid with a specific odor (yield was 0.19%). The qualitative and 
quantitative composition of the essential oil was determined by GC-MS. Components 
were identified based on a comparison of the characteristics of the mass spectra with the 
data of electronic libraries and retention indexes (RI) of the compounds, determined in 
relation to the retention time (RT) of a mixture of 
n
-alkanes (C
9
-C
34
).
72 compounds have been identified in the essential oil of 
S. subdentatus
. The 
identified components make up 90.4% of the whole oil. Dominant in the composition of 
the essential oil were 8 components out of 72 identified substances.
The main components of the essential oil were: acyclic natural monoterpene 
hydrocarbons β-myrcene (26.8%), 
cis
-β-ocymene (12.6%), 
trans
-β-ocymene (5.1%); 
monoterpene alcohol terpinen-4-ol (7.5%), monocyclic monoterpene α-terpinolene 
(3.3%), α-terpineol (3.1%), monocyclic sesquiterpenes zingiberene (2.9%) and 
m
-
cymene (2.1%). 
Thus, 72 volatile components of dominant acyclic monoterpene hydrocarbons, monocyclic 
monoterpene, bicyclic alcohol, and monocyclic sesquiterpenes were identified for the first 
time in the composition of the essential oil obtained by hydrodistillation from the aerial part of 
S. subdentatus
.