Composition and Intraspecific Chemical Variability of Leaf Essential Oil of Laggera pterodonta from Côte d'Ivoire.

The chemical composition of 44 leaf oil samples of Laggera pterodonta (DC.) Sch.Bip. ex Oliv. (Asteraceae) from Côte d'Ivoire was investigated, using combination of chromatographic (GC-FID) and spectroscopic (GC/MS, 13 C-NMR) techniques. Two oil samples chosen according to their chromatographic profiles were submitted to column chromatography and all fractions of CC were analyzed by GC-FID, GC/MS and 13 C-NMR. In total, 83 components accounting for 96.5 to 99.4 % of the whole chemical composition were identified. Significant variations were observed within terpene classes: monoterpene hydrocarbons (0.4-22.7 %), oxygenated monoterpenes (32.9-54.9 %), sesquiterpene hydrocarbons (18.6-38.3 %) and oxygenated sesquiterpenes (3.5-38.4 %). Thus, the 44 compositions were subjected to hierarchical cluster analysis (HCA) and principal component analysis (PCA). Two groups were differentiated according to their composition. All the samples contained 2,5-dimethoxy-p-cymene, α-humulene and (E)-ß-caryophyllene among the main components. Other components were present at appreciable contents and allowed differentiation of two groups: sabinene and germacrene D for Group I; 10-epi-γ-eudesmol and eudesm-7(11)-en-4α-ol for Group II. All the samples collected in Eastern Côte d'Ivoire constituted Group I, while samples collected in the Central area of the country constituted Group II.

New Natural Oxygenated Sesquiterpenes and Chemical Composition of Leaf Essential Oil from Ivoirian Isolona dewevrei (De Wild. & T. Durand) Engl. & Diels.

This study aimed to investigate the chemical composition of the leaf essential oil from Ivoirian Isolona dewevrei. A combination of chromatographic and spectroscopic techniques (GC(RI), GC-MS and 13C-NMR) was used to analyze two oil samples (S1 and S2). Detailed analysis by repetitive column chromatography (CC) of essential oil sample S2 was performed, leading to the isolation of four compounds. Their structures were elucidated by QTOF-MS, 1D and 2D-NMR as (10ßH)-1ß,8ß-oxido-cadin-4-ene (38), 4-methylene-(7αH)-germacra-1(10),5-dien-8ß-ol (cis-germacrene D-8-ol) (52), 4-methylene-(7αH)-germacra-1(10),5-dien-8α-ol (trans-germacrene D-8-ol) (53) and cadina-1(10),4-dien-8ß-ol (56). Compounds 38, 52 and 53 are new, whereas NMR data of 56 are reported for the first time. Lastly, 57 constituents accounting for 95.5% (S1) and 97.1% (S2) of the whole compositions were identified. Samples S1 and S2 were dominated by germacrene D (23.6 and 20.5%, respectively), followed by germacrene D-8-one (8.9 and 8.7%), (10ßH)-1ß,8ß-oxido-cadin-4-ene (7.3 and 8.7), 4-methylene-(7αH)-germacra-1(10),5-dien-8ß-ol (7.8 and 7.4%) and cadina-1(10),4-dien-8ß-ol (7.6 and 7.2%). Leaves from I. dewevrei produced sesquiterpene-rich essential oil with an original chemical composition, involving various compounds reported for the first time among the main components. Integrated analysis by GC(RI), GC-MS and 13C-NMR appeared fruitful for the knowledge of such a complex essential oil.

Composition and Chemical Variability of Enantia polycarpa Engl. & Diels Leaf Essential Oil from Côte d'Ivoire.

The composition of Enantia polycarpa Engl. & Diels leaf essential oil has been investigated for the first time using a combination of chromatographic and spectroscopic techniques. The compositions of 52 leaf essential oil samples have been subjected to statistical analysis, hierarchical cluster analysis (HCA) and principal component analysis (PCA). Four groups were differentiated, of which the compositions were dominated by ß-elemene and germacrene B (Group III, 22/52 samples); germacrene D (Group I, 16/52 samples); ß-cubebene (Group IV, 8/52 samples) and by germacrene B and germacrene D (Group II, 6/52 samples). A special attention was brought to the quantification of the thermolabile components, germacrene A, germacrene B and germacrene C, as well as that of their rearranged compounds, ß-elemene, γ-elemene and δ-elemene. 13 C-NMR data of ß-cubebene have been provided.

Chemical variability of Cleistopholis patens (Benth.) Engl. et Diels leaf oil from ivory coast.

The chemical composition of 48 leaf oil samples isolated from individual plants of Cleistopholis patens (Benth.) Engl. et Diels harvested in four Ivoirian forests was investigated by GC-FID (determination of retention indices), GC/MS, and (13) C-NMR analyses. The main components identified were ß-pinene (traces-59.1%), sabinene (traces-54.2%), (E)-ß-caryophyllene (0.3-39.3%), linalool (0.1-38.5%), (E)-ß-ocimene (0.1-33.2%), germacrene D (0.0-33.1%), α-pinene (0.1-32.3%), and germacrene B (0-21.2%). The 48 oil compositions were submitted to hierarchical clustering and principal components analyses, which allowed the distinction of three groups within the oil samples. The oil composition of the major group (GroupI, 33 samples) was dominated by (E)-ß-caryophyllene and linalool. The oils of Group II (eight samples) contained mainly ß-pinene and α-pinene, while those of Group III (seven samples) were dominated by sabinene, limonene, and ß-phellandrene. Moreover, the compositions of the Ivoirian C. patens leaf oils differed from those of Nigerian and Cameroonian origins.

Chemical composition of root and stem bark essential oils from Ivorian Isolona dewevrei: structural elucidation of a new natural germacrone.

The root and stem bark essential oils from Isolona dewevrei (Annonaceae), growing wild in Côte d'Ivoire, were investigated for the first time, using a combination of chromatographic [CC, GC(RI)] and spectroscopic [MS, 13C-NMR] techniques. A new natural germacrone was isolated by repetitive column chromatography carried out on a stem bark oil sample. Its structure was elucidated as germacra-1(10),4(15),5-trien-8-one by 1 D, 2 D-NMR and QTOF-MS. Ninety-six components accounting for 95.5 ± 0.8% and 95.8 ± 1.0%, respectively, for the root and stem bark essential oil samples were identified. The major compounds of root oil were cyperene (19.7 ± 1.6%) and camphene (10.1 ± 2.1%), followed by 5-isopentenylindole (6.4 ± 2.4%), ß-elemene (3.9 ± 0.3%), (Z)-α-bisabolene (3.2 ± 1.2%) and γ-gurjunene (3.2 ± 0.3%). The stem bark oil was also dominated by cyperene (29.2 ± 4.1%), followed by ß-elemene (6.2 ± 1.1%), (Z)-α-bisabolene (3.8 ± 1.0%), (E)-ß-caryophyllene (3.3 ± 0.7%) and α-copaene (2.8 ± 1.1%).

Two new eudesman-4α-ol epoxides from the stem essential oil of Laggera pterodonta from Côte d'Ivoire.

The investigation of the stem essential oil of Laggera pterodonta (DC.) Sch. Bip. ex Oliv. (Asteraceae) from Côte d'Ivoire was carried out, using a combination of chromatographic (GC-RI, CC, pc-GC) and spectroscopic (GC-MS, 13C NMR) techniques. This study led to the identification of fifty constituents of which two new natural compounds 7ß,11ß-epoxy-eudesman-4α-ol and 7α,11α-epoxy-eudesman-4α-ol. Their structures were elucidated by 1 D and 2 D NMR spectroscopy after pc-GC purifying. Finally, 98.9% of the whole composition of the oil was identified with a high amount of 2,5-dimethoxy-p-cymene (78.9%). The other significant components were α-humulene (6.2%), (E)-ß-caryophyllene (1.7%), thymyl methyl oxide (1.7%), α-phellandrene (1.5%), p-cymene (1.2%), (3αH,4ßH,6αH,1αMe)-1,6-epoxy-3-hydroxycarvotanacetone angelic acid ester (1.1%) and 10-epi-γ-eudesmol (1.0%).

Chemical findings and in vitro biological studies to uphold the use of Ficus exasperata Vahl leaf and stem bark.

Ficus exasperata Vahl, commonly known as sandpaper, is a terrestrial Afro-tropical tree used in popular medicine. Despite the existence of some works on the biological activities of this species, its chemical composition is still poorly known. The aim of this study was to extend the knowledge on the phytochemistry and biological properties of this species. Aqueous extracts from F. exasperata leaves and stem bark were analysed. Thirty-one phenolic compounds, comprising cinnamoyl derivatives, flavonoid-O-glycosides, flavonoid-mono-C-glycosides, flavonoid-di-C-glycosides and one furanocoumarin, were determined by HPLC-DAD-ESI/MSn and UPLC-ESI-QTOF-MS, 26 of them being reported for the first time in this species. The profile of organic acids, characterized by HPLC-UV, was also reported for the first time. The best radical scavenging activity was observed for the aqueous extract from leaves (IC50 values of 222.5, 510.0 and 50.0 µg/mL against DPPH•, •NO and O2•-, respectively). In addition, both aqueous extracts of the leaves and stem bark displayed a weak effect on α-amylase, and no cytotoxicity against gastric adenocarcinoma cell line, AGS. This study contributes to the valorisation of these vegetal materials, which may have application in functional foods and/or nutraceuticals.

Composition and Variability of Leaf Oil from Monodora crispata - ¹³C NMR Identification of Heat-sensitive Compounds.

The composition of four samples of essential oil isolated from the leaves of individual Monodora crispata trees growing wild in an Ivorian forest (Adiopodoum6) were investigated by a combination of chromatographic (GC(RI)) and spectrometric (GC-MS, "C NMR) techniques. In total, fifty-seven compounds accounting for 92.3-98.7% of the whole composition were identified. These oils were characterized by the preeminence of sesquiterpene hydrocarbons and the content of the main components varied substantially from sample to sample. Two samples were largely dominated by germacrene D (67.3% and 76.3%, respectively), a third sample was represented by germacrene D (28.3%), germacrene C (14.3%), δ-elemene (12.1%) and ß-elemene (9.3%) and the fourth sample was characterized by 3-dimethylallylindole (15.1%), germacrene D (12.0%) and cyperene (7.8%). C NMR spectroscopy was particularly efficient for the identification of heat-sensitive compounds.