Tran Minh Hoi

Artemisia vulgaris L. from Vietnam: Chemical Variability and Composition of the Oil Along the Vegetative Life of the Plant

Abstract Essential oils produced from a population of Artemisia vulgaris of Vietnamese origin cultivated near Hanoi were subjected to analysis by GC, GC/MS and 13C-NMR. The oils were found to contain oxygenated monoterpenes as major components (1,8-cineole, camphor and α-terpineol). The composition of these oils differed from that previously reported for Vietnamese A. vulgaris oil. Only slight differences in the composition of the oil were observed along the vegetative life of the plant. No significant difference was observed between compositions of leaf and flower oils. In addition, the combination of retention indices, GC/MS and 13C-NMR spectroscopy allowed the identification of unusual sesquiterpenes such as presilphiperfolan-9α-ol as a minor component.

Study on the volatile oil contents of Annona glabra L., Annona squamosa L., Annona muricata L. and Annona reticulata L., from Vietnam.

The volatile compounds identified from four species of Annona from Vietnam are being reported. The oils were obtained from aliquots of plant samples by steam distillation and subjected to GC and GC–MS analysis. The main compounds of Annona glabra L., were β-caryophyllene (21.5%) germacrene D (17.7%), α-cadinol (5.4%) and β-elemene (5.2%). Annona squamosa L., comprised mainly of α-pinene (1.0–11.9%), limonene (0.8–11.7%), β-cubebene (0.5–13.0%), β-caryophyllene (11.6–24.5%), spathulenol (0.8–9.0%), caryophyllene oxide (1.0–10.6%) and α-cadinol (3.3–7.8%). The significant constituents of Annona muricata L., were α-pinene (9.4%), β-pinene (20.6%), ρ-mentha-2,4(8)-diene (9.8%), β-elemene (9.1%) and germacrene D (18.1%). However, camphene (0.2–6.6%), α-copaene (2.0–7.3%), β-elemene (5.9–16.6%), β-caryophyllene (8.3–14.9%), β-bisabolene (0.4–10.2%), δ-cadinene (1.7–4.8%) and germacrene D (9.3–22.8%) were the main compounds common to samples of Annona reticulata L. There were significant amounts of sabinene (11.2% and 2.7%; leaf and stem bark) and bicycloelemene (9.6% and 6.1%; stem and bark).

Chemical compositions of the leaf essential oils of some Annonaceae from Vietnam

The leaf oils of some genus of Annonaceae collected from Vietnam in December 2009 were analyzed by capillary gas chromatography (GC) and GC coupled with mass spectrometry (GC/MS). The major compounds identified in the oil of Artabotrys pallens Ast. were α-gurjunene (21.9%), α-phellandrene (20.1%) and bicycloelemene (9.6%). The oil of Goniothalamus tamirensis Pierre ex Finet & Gagnep. contained β-selinene (12.3%), bicyclogermacrene (10.9%), caryophyllene oxide (10.4%) and bicycloelemene (5.6%) in abundance. However, β-pinene (33.4%), α-pinene (32.3%) and β-caryophyllene (10.5%) were the most quantitative significant constituents of Dasymaschalon rostratum Merr. & Chun. From the oil of Uvaria pierrei Finet & Gagnep. we could identified bicycloelemene (18.3%), germacrene D (30.2%), bicyclogermacrene (26.4%) and β-bisabolene (7.7%) as the major compounds, while γ-elemene (54.0%) was the most singly abundant constituent of Uvaria dac Pierre ex Finet & Gagnep oil. All the other compounds were identified in amount less than 5% with the most prominent ones being myrcene (3.8%) and limonene (3.8%). In addition, the oil of Melodorum vietnamensis Ban., had an abundance of α-pinene (15.4%), bicyclogermacrene (13.9%), bicycloelemene (10.8%) and β-caryophyllene (9.9%). The chemotaxonomic importance of the results was also discussed.

Composition and antimicrobial activity of the essential oil of Acronychia pedunculata (L.) Miq. from Vietnam

The chemical composition and the antimicrobial activity of the essential oil isolated from aerial parts of Acronychia pedunculata (L.) Miq. from Vietnam are reported. Analysis was carried out by GC (RI), GC–MS and 13C NMR. Thirty-four compounds were identified, accounting for 92.8% of the oil. The major constituents were α-pinene (57.4%) and (E)-β-caryophyllene (13.6%). The essential oil of A. pedunculata was shown to possess a broad spectrum of antimicrobial activity against various bacteria, particularly Salmonella enterica and Staphylococcus epidermidis.

Artocarpus nigrifolius : Cytotoxic and antibacterial constituents

Six known compounds including α-amyrin 3-acetate (1), β-sitosterol (2), betulinic acid (3), friedelan-3-one (4), artochamin B (5), and 2-C-methyl-d-erythritol 4-O-α-d-glucopyranoside (6) were isolated from the stem barks and leaves of Artocarpus nigrifolius (Moraceae) for the first time. Their structures were identified by spectroscopic methods as well as comparison with literatures. Cytotoxicity and antibacterial activity of 1–6 were evaluated. Results showed that artochamin B (5) possessed the highest cytotoxicity towards MCF7, Lu, HepG2, and KB cell lines with IC50 values of 4.59, 20.00, 3.60, and 1.18 μg/mL, respectively. It also inhibited the growth of Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus), whereas inactive on the growth of both Gram-negative bacteria and yeast.

Chemical composition of leaf and stem oils from Vietnamese Cupressus tonkinensis Silba.

Cupressus tonkinensis was treated for a long time as a synonym of Cupressus torulosa D. Don. and it was proposed as new species in 1994. The two species differed by morphological characters and they were distinct in their random amplified polymorphic DNAs (RAPDs). Leaves and stems of C. tonkinensis produce monoterpene-rich oils whose composition is investigated here for the first time by combination of chromatographic and spectroscopic techniques. α-Pinene (23.1%), sabinene (21.0%) and terpinen-4-ol (14.4%) were the major components of the leaf oil that contained also β-elemol (4.2%). In contrast, α-pinene (42.5%) was by far the major component of the stem oil beside myrcene (10.2%) and cedrol (9.0%).

Volatile components of Bursera tonkinensis Guill

Abstract Bursera tonkinensis leaf and fruit oil was analysed by GC/RI, GC/MS and 13C-NMR. The main constituents were α-phellandrene (70.1%), β-phellandrene (8.4%) and α-pinene (7.6%). This oil is different to those produced from the majority of Bursera species.

Integrated Analysis of the Wood Oil from Xanthocyparis vietnamensis Farjon & Hiep. by Chromatographic and Spectroscopic Techniques

In order to get better knowledge about the volatiles produced by Xanthocyparis vietnamensis, a species recently discovered in Vietnam, its wood oil has been analyzed by a combination of chromatographic (GC, CC) and spectroscopic (GC-MS, 13C-NMR) techniques. Forty components that accounted for 87.9% of the oil composition have been identified. The composition is dominated by nootkatene (20.7%), 11,12,13-tri-nor-eremophil-1(10)-en-7-one (17.2%), γ-eudesmol (5.1%), nootkatone (4.7%), valencene (3.5%) and 13-nor-eremophil-1(10)-en-11-one (2.6%). The structure of two new compounds—10-epi-nor-γ-eudesmen-11-one and 12-hydroxy-isodihydroagarofuran—has been elucidated, while 11,12,13-tri-nor-eremophil-1(10)-en-7-ol is reported as a natural product for the first time. The composition of X. vietnamensis wood oil varied drastically from those of leaf oils, dominated by hedycaryol (34.4%), phyllocladene (37.8%) or by pimara-6(14)-15-diene (19.4%).

Terpene constituents of the leaves of five Vietnamese species of Clausena (Rutaceae)

This article reports the compounds identified in the leaf oils of five Clauseana species growing in Vietnam. The hydrodistilled oils were analysed for their chemical constituents by using gas chromatography–flame ionisation detector and gas chromatography coupled with mass spectrometry. The major compounds identified in Clausena dentata (Willd.) M. Roem. were α-pinene (21.7%), sabinene (18.3%) and β-myrcene (14.3%). Clausena dimidiata Tanaka comprised mainly of safrole (56.9%) and α-terpinolene (22.1%). However, 1-menthone (70.6%) and β-phellandrene (13.0%) were the most abundant compounds of Clausena indica (Dalz.) Oliver. Sesquiterpene compounds represented mainly by β-caryophyllene (16.7%), spathulenol (11.9%) and bicyclogermacrene (7.5%) were the major constituents of Clausena excavata Burm. f., while those of Clausena engleri Tanaka include bicycloelemene (12.1%), bicyclogermacrene (11.0%) and (E)-nerolidol (6.6%). This is the first report on the chemical analysis of essential oils of C. dimidiata and C. engleri.

Chemical Constituents of Essential Oil from the Leaf of Euodia meliaefolia (Hance) Benth. Grown in Vietnam

Abstract The chemistry of essential oil obtained by hydrodistillation of the leaf of Euodia meliaefolia (Hance) Benth., grown in Vietnam were being reported. The oil was analyzed by means of gas chromatography-flame ionisation detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS) techniques. The constituents of the essential oils were identified by comparison of their retention indices and mass spectra with authentic compounds. Sixty compounds representing 93.4 % of the total content were identified in the essential oil of E. meliaefolia. Monoterpene hydrocarbons (25.8 %), oxygenated monoterpenes (39.3 %) and aliphatic compounds (14.7 %) represent the main classes of compounds present in the oil. The main constituents of the oil which are mainly monoterpene compounds were linalool (17.1 %), β-phellandrene (12.4%), geranial (11.2%) and α-pinene (7.4%). The present study may represent the first report on the chemical composition of volatile oil of E. meliaefolia.