Antimicrobial activity of the essential oils from the leaves and stems of Amomum rubidum Lamxay & N. S. Lý / Actividad antimicrobiana de los aceites esenciales de las hojas y tallos de Amomum rubidum Lamxay & N. S. Lý

This paper described the chemical compositions and antimicrobial activity of the essential oils from the leaves and stem of Amomum rubidumLamxay & N. S. Lý, collected from Bidoup Nui Ba National Park, Lam Dong, Vietnam. The essential oils were obtained by hydrodisitllation method while antimicrobial activity was evaluetd by microdilution broth susceptibility assay. The main constituents of the leaf essential oil were identified as 1,8-cineole (37.7%), δ-3-carene (19.5%) and limonene (16.3%) while δ-3-carene (21.9%), limonene (17.8%) and ß-phellandrene (14.6%) dominated in the stem essentialoil. The leaf and stem essential oils displayed stronger inhibition of Pseudomonas aeruginosa with MIC of 25 µg/mLand 50 µg/mL respectively. The stem essential oil was active against Candida albicans (MIC, 50 µg/mL) while both essential oils inhibited the growth of Fusarium oxysporum (MIC 50 µg/mL). This is the first report on chemical constituents and antimicrobial activity of the essential oils of A. rubidum.

Este artículo describe la composición química y la actividad antimicrobiana de aceites esenciales de las hojas y el tallo de Amomum rubidum Lamxay & N. S. Lý recolectados del Parque Nacional Bidoup Nui Ba, Lam Dong, Vietnam. Los aceites esenciales se obtuvieron mediante el método de hidrodisitilación, mientras que la actividad antimicrobiana se evaluó mediante un ensayo de susceptibilidad de caldo de microdilución. Los principales componentes del aceite esencial de la hoja se identificaron como 1,8-cineol (37,7%), δ-3-careno (19,5%) y limoneno (16,3%), mientras que δ-3-careno (21,9%), limoneno (17,8 %) y ß-felandreno (14,6%) dominaron en el aceite esencial del tallo. Los aceites esenciales de hoja y tallo mostraron una inhibición más fuerte de Pseudomonas aeruginosa con un MIC de 25 µg/mL y 50 µg/mL, respectivamente. El aceite esencial del tallo fue activo contra Candida albicans (MIC, 50 µg/mL) mientras que ambos aceites esenciales inhibieron el crecimiento de Fusarium oxysporum (MIC 50 µg/mL). Este es el primer informe sobre los componentes químicos y la actividad antimicrobiana de los aceites esenciales de A. rubidum.

Chemical Compositions, Mosquito Larvicidal and Antimicrobial Activities of Essential Oils from Five Species of Cinnamomum Growing Wild in North Central Vietnam.

Members of the genus Cinnamomum (Lauraceae) have aromatic volatiles in their leaves and bark and some species are commercially important herbs and spices. In this work, the essential oils from five species of Cinnamomum (C. damhaensis, C. longipetiolatum, C. ovatum, C. polyadelphum and C. tonkinense) growing wild in north central Vietnam were obtained by hydrodistillation, analyzed by gas chromatography and screened for antimicrobial and mosquito larvicidal activity. The leaf essential oil of C. tonkinense, rich in ß-phellandrene (23.1%) and linalool (32.2%), showed excellent antimicrobial activity (MIC of 32 µg/mL against Enterococcus faecalis and Candida albicans) and larvicidal activity (24 h LC50 of 17.4 µg/mL on Aedes aegypti and 14.1 µg/mL against Culex quinquefasciatus). Cinnamomum polyadelphum leaf essential oil also showed notable antimicrobial activity against Gram-positive bacteria and mosquito larvicidal activity, attributable to relatively high concentrations of neral (11.7%) and geranial (16.6%). Thus, members of the genus Cinnamomum from Vietnam have shown promise as antimicrobial agents and as potential vector control agents for mosquitoes.

Essential oils Constituents of the leaves of Amomum gagnepainii and Amomum repoense.

The chemical constituents identified in the essential oils hydrodistilled from the leaves of Amomum gagnepainii T.L.Wu, K.Larsen and Turland and Amomum repoense Pierre ex Gagnep (Zingiberaceae) of Vietnam origin are reported. The chemical analyses were performed by means of gas chromatography-flame ionisation detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). The main compounds of A. gagnepainii were farnesyl acetate (18.5%), zerumbone (16.4%) and ß-caryophyllene (10.5%). On the other hand, Amomum repoense comprised of monoterpenes dominated by ß-pinene (33.5%), (E)-ß-ocimene (9.6%), γ-terpinene (9.1%) and α-pinene (8.4%). This is the first report on the essential oils of A. gagnepainii and A. repoense grown in Vietnam or elsewhere.

Volatile constituents of Atalantia roxburghiana Hook. f., Tetradium trichotorum Lour. and Macclurodendron oligophlebia (Merr.) Hartl. (Rutaceae) from Vietnam / Compuestos volátiles de Atalantia roxburghiana Hook. f., Tetradium trichotorum Lour. y Macclurodendron oligophlebia (Merr.) Hartl. (Rutaceae) provenientes de Vietnam

The chemical constituents of essential oils obtained by hydrodistillation of the leaves of Atalantia roxburghiana Hook. f. and Tetradium trichotomum Lour., as well as the leaves and fruits of Macclurodendron oligophlebia (Merr.) Hartl. (Rutaceae) are being reported. The essential oils were analysed by using gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC-MS). Sabinene (36.9%) was the most singly abundant compound in the leaf of A. roxburghiana. The major constituents present in the leaf oil of T. trichotorum were (E)-ß-ocimene (24.8%), α-pinene (10.4%), (Z)-ß-ocimene (9.4%) and ß-caryophyllene (8.0%). On the other hand, while α-pinene (17.5%), ß-caryophyllene (15.5%) and caryophyllene oxide (10.6%) occurred in higher proportion in the leaf of M. oligophlebia, the fruit oil was dominated by benzyl benzoate (16.8%), (E, E)-farnesol (8.3%) and ß-caryophyllene (6.0%).

Se muestran los constituyentes químicos de los aceites esenciales obtenidos, por hidrodestilación, de las hojas de Atalantia roxburghiana Hook. f. y de Tetradium trichotomum Lour., así como de las hojas y frutos de Macclurodendron oligophlebia (Merr.) Hartl. (Rutaceae). Los aceites esenciales fueron analizados por Cromatografía de Gases (CG) y por Cromatografía de Gases acoplada a Espectrometría de Masas (CG-EM). El compuesto más abundante en las hojas de A. roxburghiana es el sabineno (36.9%); mientras que los mayoritarios en el aceite de las hojas de T. trichotomum fueron (E)-ß-ocimeno (24.8%), α-pineno (10.4%), (Z)-ß-ocimeno (9.4%) y ß- cariofileno (8.0%). En las hojas de M. oligophlebia los compuestos más abundantes fueron α-pineno (17.5%), ß-cariofileno (15.5%) y óxido de cariofileno (10.6%); sin embargo, en el aceite obtenido del fruto fueron benzoato de bencilo (16.8%), (E, E)-farnesol (8.3%) y ß- cariofileno (6.0%).

Constituents of essential oils from the leaf, stem, root, fruit and flower of alpinia macroura k. schum / Constituyentes de los aceites esenciales de las hojas, tallo, raíz y flores de alpinia macroura k. schum

This paper reports the chemical constituents of essential oils from the various parts of Alpinia macroura K. Schum (Zingiberaceae) from Vietnam. The essential oils were obtained by hydrodistillation and analysed by means of gas chromatography coupled to Flame ionization detector (GC-FID) and gas chromatography coupled to mass spectrometry (GC/MS). The main constituents of the oils were beta-pinene (8.8 percent-16.4 percent), 1,8-cineole (5.5 percent-17.7 percent), upsilon-terpinene (5.9 percent-16.9 percent), alpha-pinene (4.5 percent-8.4 percent) and beta-caryophyllene (1.4 percent-18.6 percent). Sabinene (9.0 percent) was identified only in the fruit. Overall, nineteen of the identified compounds are coming to all the essential oils. The chemical constituents of essential oils from the leaf, stem, root, fruit and flower of A. macroura are being reported for the first time and were found to be different from those of other Alpinia oils.

En este trabajo se presentan los componentes químicos de los aceites esenciales de las distintas partes de Alpinia macroura K. Schum (Zingiberaceae) de Vietnam. Los aceites esenciales se obtuvieron por hidrodestilación y se analizaron por medio de cromatografía de gases acoplada a detector de ionización de llama (GC-FID) y cromatografía de gases acoplada a espectrometría de masas (GC/MS). Los principales constituyentes de los aceites fueron beta-pineno (8,8 por ciento -16,4 por ciento), 1,8-cineol (5,5 por ciento -17,7 por ciento), ípsilon-terpineno (5,9 por ciento -16,9 por ciento), alfa-pineno (4,5 por ciento -8,4 por ciento) y beta-cariofileno (1,4 por ciento -18,6 por ciento). Sabineno (9,0 por ciento) fue identificado solamente en la fruta. En general, diecinueve de los compuestos identificados están llegando a todos los aceites esenciales. Los componentes químicos de los aceites esenciales de la hoja, tallo, raíz, frutas y flores de A. macroura están siendo reportados por primera vez y se encontró que eran diferentes de las de otros aceites de Alpinia.

Analysis and Olfactory Description of Four Essential Oils from Vietnam.

The present study evaluates the chemical composition and olfactory description of the essential oils of Asarum glabrum Merr., Calocedrs macrolepis Kurz, Cunninghamia lanceolata (Lamb.) Hook. and Glyptostrobus pensilis (Stainton ex D.Don) K. Koch. The essential oils were obtained by hydrodistillation in a Clevenger-type apparatus and analyzed by GC-FID and GC-MS. Concerning their chemical composition, 66, 42, 57 and 21 volatile compounds were identified from dried leaves in the case of Asarum glabrum Merr. and wood for the other three, representing 98.7%, 67.2%,,92.0% and 87.5 % of the total composition, respectively. The main compounds of Asarum glabrum oil were safrole (38.1%), apiole (10.8%) and myristicin (8.0%); of Calocedrus macrolepis verbenone (9.3%), piperitone (8.6 %), a-terpineol (6.0%) and (Z)-p-terpineol (5.3%); of Cunninghamia lanceolata oil cedrol (26.3%), a-terpineol (24.1%) and camphor (7.0%); and of Glyptostrobus pensilis oil dihydro-eudesmol isomer (assumed) (18.3%), cedrol (16.4%), occidentalol (13.2%) and elemol (9.0%).

Fatty Acid Methyl Ester Composition of Some Turkish Apiaceae Seed Oils: New Sources for Petroselinic Acid.

The seed oils of twenty-six species of Apiaceae belonging to the genera Bunium, Cnidium, Ferula, Ferulago, Heracleum, Hippomarathrum, Malabaila, Myrrhoides, Olymposciadium, Pimpinella, Prangos, Szovitsia, Trigonasciadium, Trinia and Zosima, collected in Turkey, were investigated for their oil content, and amount of petroselinic acid (PA), as well as for the composition of their fatty acid methyl esters (FAMEs) by GC-MS. Seed oil content ranged from 7.1% in Szovitsia callicarpa to 29.3% in Ferda haussknechtii. The results showed that the seed oils of the studied species contained high amounts of PA (1.2-72.2%), followed by significant amounts of linoleic (LA, 13.8-50.8%) and oleic (OA, 4.2-61.6%) acids. PA was found in all the analyzed species, except for Olymposciadium caespitosum, which belongs to a monotypic endemic genus of the family. According to data from our study, PA was found to be predominantly in the seed oils of Hippomarathrum cristatum (72.2%), Trinia glauca (64.9%) and Bunium microcarpum (59.7%) and, therefore these species might be considered as new sources of PA, and represent a potential oleochemical raw material. This is the first extensive study of the composition ofTurkish Apiaceae species. The high amounts of PA may also have chemotaxonomic significance.

Chemical Composition of Vietnamese Essential Oils of Cinnamomum rigidifolium, Dasymaschalon longiusculum, Fissistigma maclurei and Goniothalamus albiflorus.

Cinnamomum rigidifolium, Dasymaschalon longiusculum, Fissistigma maclurei and Goniothalamus albiflorus were collected from different landscapes in Vietnam and hydro distilled to produce essential oils with yields from 0.15 - 0.35%. The oils were analyzed by GC-MS-FID and rechecked by measurements on two different instrumentation configurations. The main components of the studied essential oils were for Cinnamomum rigidifolium linalool (19.4%), α-pinene (13.8%), verbenone (9.9%) and cis-verbenol (8.9%), total identified 90.5%; for Dasymaschalon longiusculum spathulenol (21.4%), caryophyllene oxide (17.6%), a-pinene (5.5%) and ß-pinene (5.2%), total identified 70.1%; for Fissistigma maclurei spathulenol (17.8%), guaia-6,10(14)-diene-40-ol (10.3%), (E)-ß-caryophyllene (7.3%) and caryophyllene oxide (7.0%), total identified 75.3% and for Goniothalamus albiflorus 1,8-cineole (13.2%), α-pinene (10.6%), ledol (7.5%) and caryophyllene oxide (7.3%), total identified 78.0%.

Study on essential oils from the leaves of two Vietnamese plants: Jasminum subtriplinerve C.L. Blume and Vitex quinata (Lour) F.N. Williams.

The essential oil constituents of the leaves of Jasminum subtriplinerve (Oleaceae) and Vitex quinata (Verbanaceae) cultivated in Vietnam were analysed by gas chromatography--flame ionisation detector (GC-FID) and gas chromatography--mass spectrometry (GC-MS) techniques. The main constituents identified in J. subtriplinerve were mainly oxygenated monoterpenes represented by linalool (44.2%), α-terpineol (15.5%), geraniol (19.4%) and cis-linalool oxide (8.8%). The quantitative significant components of V. quinata were terpene hydrocarbons comprising of ß-pinene (30.1%), ß-caryophyllene (26.9%) and ß-elemene (7.4%). The chemical compositions of the essential oils are being reported for the first time.

Constituents of essential oils from the leaves, stems and roots of Zingiber gramineum and Zingiber rufopilosum / Los constituyentes de los aceites esenciales de las hojas, tallos y raíces de Zingiber gramineum y Zingiber rufopilosum

The chemical constituents of essential oils obtained from leaves, stems and roots of Zingiber gramineum Noronha ex Blume and Zingiber rufopilosum Gagnep collected from Vietnam have been studied. The determination of essential oil components was performed by Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography- Mass Spectrometry (GC-MS). The main constituents of the leaves oil of Zingiber gramineum were zingiberene (19.5 percent), beta-cubebene (12.9 percent), beta-sesquiphellandrene (12.9 percent) and beta-elemene (11.6 percent) while the stems oil was dominated by benzyl benzoate (22.6 percewnt), beta-elemene (9.7 percent) and beta-selinene (8.8 percent). However, upsilon-terpinene (17.9 percent), alpha-terpinene (17.1 percent), terpinen-4-ol (13.0 percent) and 1,8-cineole (12.8 percent) were the present in the root oil. In addition, beta-agarofuran (13.7 percent), alpha-humulene (8.8 percent) and alpha-pinene (8.7 percent) were the main compounds identified in the leaves of Zingiber rufopilosum. The stems comprised of alpha-cadinol (15.1 percent), beta-muurolol (12.1 percent) and endo-1-bourbonanol (9.9 percent) while (E,E)-farnesol (11.6 percent), alpha-pinene (10.0 percent), bornyl acetate (6.6 percent) and beta-pinene (6.2 percent) were the significant compounds of the root oil. This is the first report on the volatile compositions of these plant species.

El presente estudio se llevó a cabo para evaluar el efecto del extracto metanólico acuoso a partir de los componentes químicos de los aceites esenciales obtenidos de las hojas, tallos y raíces de Zingiber gramineum Noronha ex Blume y Zingiber rufopilosum Gagnep recogidos de Vietnam. La determinación de componentes de aceites esenciales se realizó por cromatografía de gases-detector de ionización de llama (GC-FID) y cromatografía de gases espectrometría de masas (GC-MS). Los principales componentes del aceite de hojas de Zingiber gramineum fueron zingibereno (19,5 por ciento), beta-cubebene (12,9 por ciento), beta-sesquiphellandrene (12,9 por ciento) y beta-elemene (11,6 por ciento), mientras que el aceite de tallos fue dominada por benzoato de bencilo (22,6 por ciento), beta-elemene (9,7 por ciento) y beta-selineno (8,8 por ciento). Sin embargo, ipsilon-terpineno (17,9 por ciento), alfa-terpineno (17,1 por ciento), terpinen-4-ol (13,0 por ciento) y 1,8-cineol (12,8 por ciento) fueron los presentes en el aceite de la raíz. Además, beta-agarofuran (13,7 por ciento), alfa-humuleno (8,8 por ciento) y alfa-pineno (8,7 por ciento) fueron los principales compuestos identificados en las hojas de Zingiber rufopilosum. Los tallos componen de alfa-cadinol (15,1 por ciento), beta-muurolol (12,1 por ciento) y endo-1-bourbonanol (9,9 por ciento), mientras que (E, E)-farnesol (11,6 por ciento), alfa-pineno (10,0 por ciento), acetato de bornilo (6,6 por ciento) y beta-pineno (6,2 por ciento) fueron los compuestos significativos del aceite de la raíz. Este es el primer informe sobre las composiciones volátiles de estas especies de plantas.

Essential oil constituents of Etlingera yunnanensis and Hornstedtia sanhan grown in Vietnam.

The chemical composition of the essential oils obtained from the hydrodistillation of different parts of Etlingera yunnanensis (T.L. Wu & S.J. Chen) R.M. Sm. and Hornstedtia sanhan M.F. Newman (Zingiberaceae) grown in Vietnam are reported. The analysis was performed by means of a gas chromatography-flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). The essential oil of the leaves of E. yunnanensis comprised mainly germacrene D (19.2%), ß-pinene (11.6%), and α-amorphene (11.2%), while that of the stems was rich in ß-pinene (23.7%), 1,8-cineole (11.0%) and α-pinene (9.6%). The major components of the root oil of E. yunnanensis were ß-pinene (31.9%), α-pinene (13.7%) and 1,8-cineole (9.4%). However, α-pinene (25.9%, 36.3% and 14.1% for leaves, stems and roots, respectively), ß-pinene (9.7%, 11.8% and 7.2% for leaves, stems and roots, respectively) and limonene (22.1%, 24.6% and 16.2% for leaves, stems and roots, respectively) were the major compounds of H. sanhan. In addition, α-humulene (15.9%) was present in larger amounts in the leaf oil while the root oil contained the largest proportion of methyl chavicol (43.7%).

Volatile constituents of Amomum maximum Roxb and Amomum microcarpum C. F. Liang & D. Fang: two Zingiberaceae grown in Vietnam.

The chemical composition of essential oils obtained from the hydrodistillation of different parts of Amomum maximum Roxb and Amomum muricarpum C. F. Liang & D. Fang (Zingiberaceae) grown in Vietnam are reported. The analysis was performed by means of gas chromatography-flame ionisation detectoorand gas chromatography coupled with mass spectrometry. The major compounds identified in the oils of A. maximum were ß-pinene (20.4-40.8%), α-pinene (6.8-15.0%), ß-elemene (2.5-12.8%) and ß-caryophyllene (2.3-10.3%). Moreover, ß-phellandrene (11.6%) was present in the root oil. The main compound identified in all the oil samples of A. muricarpum was α-pinene (24.1-54.7%) and ß-pinene (9.2-25.9%). In addition, limonene (7.4%) and δ-3-carene (9.4%) were present in the leaves and stem oils, respectively. However, while ß-phellandrene (8.3%) could be seen prominent in the root oil, the fruits contained significant amount of zingiberene (6.3%). The largest amount of τ-muurolol (13.0%) was found in the flower oil.

Study on Cinnamomum oils: compositional pattern of seven species grown in Vietnam.

The leaf essential oils of seven Vietnamese species of the genus Cinnamomum were analyzed by gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC/MS). The results showed that the species fall into three groups in which one group contains aromatic components, while the second group contains both terpenes and aromatic constituents and the third group contains only terpene constituents. The first group had only Cinnamomum curvifolium as its member and produced oil rich in benzyl cinnamate and benzyl benzoate. The second group producing mixture of phenylpropanoids and oxygenated monoterpene components includes leaves of Cinnamomum kunstleri (methyl eugenol, terpinen-4-ol and 1,8-cineole) and Cinnamomum mairei (eugenol, 1, 8-cineole, neryl acetate and eugenol acetate). The third group rich in terpene constituents could also be divided into two classes. The first class produced oils rich in monoterpene components and includes Cinnamomum damhaensis (linalool, α-pinene, ß-pinene and 1,8-cineole), Cinnamomum cambodianum (linalool and terpinen-4-ol) and Cinnamomum caryophyllus (1,8-cineole, α-pinene and camphene). The second class contains oil with abundance of sesquiterpene compounds and peculiar to Cinnamomum rigidifolium (α-selinene, ß-caryophyllene and α-copaene). This paper discusses further the chemotaxonomic importance of these results and previous data on essential oils of Cinnamomum species analysed from Vietnam.

Composition of essential oils of four Hedychium species from Vietnam.

BACKGROUND: Vietnam is a country blessed with many medicinal plants widely used as food and for medicinal purposes, and they contain a host of active substances that contribute to health. However, the analysis of chemical constituents of these plant species has not been subject of literature discussion. RESULTS: In this study, the chemical compositions of essential oils of four Hedychium species, obtained by hydrodistillation, were determined by means of gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS) techniques. Individually, α-pinene (52.5%) and ß-pinene (31.8%) were present in the leaf oil of Hedychium stenopetalum Lodd., while linalool (45.2%), (E)-nerolidol (8.7%) and α-pinene (5.0%) were identified in the root. The leaf of Hedychium coronarium J. König was characterized by ß-pinene (20.0%), linalool (15.8%), 1,8-cineole (10.7%), α-pinene (10.1%) and α-terpineol (8.6%); while ß-pinene (23.6%), α-humulene (17.1%) and ß-caryophyllene (13.0%) were identified in the root. Hedychium flavum Roxb., gave oil whose major compounds were ß-pinene (22.5%), α-humulene (15.7%) and ß-caryophyllene (10.4%) in the leaf; α-humulene (18.9%), ß-caryophyllene (11.8%) and ß-pinene (11.2%) in the stem, as well as ß-pinene (21.8%), linalool (17.5%) and 1,8-cineole (13.5%) in the root. The main constituents of Hedychium ellipticum Buch.-Ham. ex Smith were (E)-nerolidol (15.9%), ß-pinene (11.8%) and bornyl acetate (9.2%) in the leaf with 1,8-cineole (40.8%), α-pinene (18.3%) and ß-pinene (11.0%) occurring in the root. CONCLUSIONS: Ubiquitous monoterpenes and sesquiterpenes were identified as characteristic markers for Hedychium species. This work is of great importance for the evaluation of Hedychium essential oils grown in Vietnam.

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 ß-myrcene (14.3%). Clausena dimidiata Tanaka comprised mainly of safrole (56.9%) and α-terpinolene (22.1%). However, 1-menthone (70.6%) and ß-phellandrene (13.0%) were the most abundant compounds of Clausena indica (Dalz.) Oliver. Sesquiterpene compounds represented mainly by ß-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 oils from the leaves and stem barks of four Vietnamese species of Fissistigma (Annonaceae).

Chemical profiles of essential oils from four Fissistigma species: Fissistigma bracteolatum Chatt., Fissistigma villosissimum Merr., Fissistigma latifolium (Dunal) Merr. and Fissistigma glaucescens (Hance) Merr. were analysed by gas chromatography-flame ionisation detector and gas chromatography-mass spectrometry. Fissistigma essential oils consist mainly of sesquiterpenes (48.7-83.8%), monoterpenes (3.2-30.9%) and fatty acids (0.5-33.4%). Data on the essential oil composition of F. villosissimum, F. latifolium and F. glaucescens are reported for the first time.

Chemical composition of essential oils from the leaves and stem barks of Vietnamese species of Polyalthia harmandii, Polyalthia jucunda and Polyalthia thorelii.

This article reports the chemical components identified in the essential oil from the leaf and stem barks of Polyalthia harmandii (Pierre) Fin. and Gagnep., Polyalthia jucunda (Pierre) Fin. and Gagnep. and Polyalthia thorelii (Pierre) Fin. and Gagnep. The compounds identified in all the samples were α-pinene (0.2-3.2%), myrcene (0.3-4.1%), (E)-ß-ocimene (0.2-9.6%), bicycloelemene (0.2-18.0%), ß-elemene (0.3-4.9%), ß-caryophyllene (0.1-17.8%), germacrene D (4.4-20.1%), bicyclogermacrene (4.2-27.9%) and δ-cadinene (0.2-4.5%). Besides, benzyl benzoate (9.7%) and ishwarane (8.0%), respectively, were the other prominent compounds in the leaf and stem of P. harmandii. In addition, δ-3-carene (8.2%), α-amorphene (6.5%), ß-phellandrene (5.5%) and ß-pinene (5.1%) were identified in P. jucunda leaf, while sabinene (30.9%) and ß-phellandrene (10.2%) occurred largely in the stem. Moreover, γ-elemene (22.3% and 12.3%), germacrene D (10.5% and 6.9%) and spathulenol (9.1% and 11.8%) were identified in the leaf and stem of P. thorelii, while α-terpinene (7.8%) and ß-gurjunene (5.2%) were identified only in the leaf oil.

Constituents of essential oils from the leaves, stem barks and resins of Canarium parvum Leen., and Canarium tramdenanum Dai et Yakovl. (Burseracea) grown in Vietnam.

The chemical constituents of essential oils from the leaf, stem bark and resins of Canarium parvum Leen., and Canarium tramdenanum Dai et Yakovl. (Burseracea) grown in Vietnam are being reported. The hydrodistilled oils were analysed for their chemical constituents by means of gas chromatography-flame ionisation detector and gas chromatography coupled with mass spectrometry. The main compounds of C. parvum were ß-caryophyllene (18.7%), (E)-ß-ocimene (12.9%), (Z)-ß-ocimene (11.9%), germacrene D (8.8%) and α-humulene (8.4%) in the leaf; ß-caryophyllene (30.4%), α-copaene (20.5%) and (E)-ß-ocimene (7.7%) in the stem. However, germacrene D (23.2%), α-amorphene (14.9%), α-copaene (9.8%) and ß-elemene (8.6%) were present in the resin. The leaf of C. tramdenanum comprises ß-caryophyllene (16.8%), α-phellandrene (15.9%), γ-elemene (13.1%) and limonene (11.8%), while limonene (25.7%), α-phellandrene (21.7%), α-pinene (12.3%) and ß-caryophyllene (10.9%) were present in the stem. However, δ-elemene (14.6%) and bulnesol (16.0%) are the main constituents in the resin.

Chemical composition of the leaf oil of Actephila excelsa from Vietnam..

Fresh leaves of Actephila excelsa (Dazl.) Muell. from Vietnam were steam distilled to produce an oil in a yield of 0.15% (v/w). The essential oil was analyzed by a combination of capillary gas chromatography-flame ionization detection (GC-FID) and gas chromatography coupled with mass spectrometry (GC/MS). The main constituents of the oil were the sesquiterpenes γ-elemene (25.7%) and ß-caryophyllene (11.2%). Other significant compounds were methyl salicylate (5.8%), benzyl benzoate (5.2%), (E,E)-farnesylacetone (4.9%), anisole (4.7%), sabinene (4.1%) and menthone (4.0%). This is the first report on the volatile constituents of this plant.

Analysis of essential oil constituents of three Dasymaschalon species (Annonaceae) from Vietnam.

The compositions of essential oils of the leaves and stem barks of three Vietnamese species of Dasymaschalon J. D. Hooker & Thomson. (Annonaceae) were determined by means of gas chromatography and gas chromatography-mass spectrometry. Dasymaschalon longiusculum (Bân) yielded oils in which the major components were α-pinene (28.9% and 12.5%, respectively), ß-pinene (26.5% and 13.3%, respectively), ß-myrcene (12.0% and 6.0%, respectively) for the leaf and stem. The main compounds of the leaf and stem oils of Dasymaschalon glaucum Merr. & Chun. were α-pinene (14.4% and 10.5%, respectively), ß-pinene (14.4% and 10.3%, respectively) and bicycloelemene (5.2% and 30.0%, respectively). The essential oil of Dasymaschalon robinsonii Jovet-Ast was different, mainly comprising α-copaene (12.7% and 16.6%, respectively), germacrene B (11.3% and 7.5%, respectively), δ-cadinene (5.6% and 5.3%, respectively) for the leaf and stem.