Secondhand smoke in public places in Vietnam: An assessment 5 years after implementation of the tobacco control law.

OBJECTIVES: This study quantified the secondhand smoke (SHS) concentration in a sample of public places in Vietnam to determine changes in SHS levels 5 years after a public smoking ban was implemented. METHODS: Two monitoring campaigns, one in 2013 (before the tobacco control law was implemented) and another in 2018 (5 years after the implementation of the law) were conducted in around 30 restaurants, cafeterias and coffee shops in major cities of Vietnam. Concentrations of PM2.5, as an indicator of SHS, were measured by portable particulate matter monitors (TSI SidePak AM510 and Air Visual Pro). RESULTS: The geometric mean PM2.5 concentration of all monitored venues was 87.7 µg/m3 (83.7-91.9) in the first campaign and 55.2 µg/m3 (53.7-56.7) in the second campaign. Pairwise comparison showed the PM2.5 concentrations in the smoking observed area was triple and double those in the non-smoking area and the outdoor environment. After adjusting for sampling locations and times, the SHS concentration 5 years after the implementation of the tobacco control law reduced roughly 45%. CONCLUSION: The study results indicate an improvement in air quality in public places in Vietnam via both the reduction in PM2.5 levels and the number of people observed smoking. However, greater enforcement of the free-smoke legislation is needed to eliminate SHS in public places in Vietnam.

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.

Mosquito Larvicidal Activity of the Essential Oil of Zingiber collinsii against Aedes albopictus and Culex quinquefasciatus.

The chemical composition and larvicidal activity of essential oils from the leaves and rhizomes of Zingiber collinsii Mood & Theilade (Zingiberaceae) were reported. The main compounds in the leaf oil were α-pinene (25.6%), ß-caryophyllene (16.8%), ß-pinene (16.1%) and bicyclogermacrene (6.9%) while the rhizome oil consist mainly of camphene (22.5%), ß-pinene (16.3%), α-pinene (9.0%) and humulene oxide II (9.0%). The rhizome oil demonstrated larvicidal effects towards fourth instant larvae of mosquito vectors. The highest mortality (100%) was observed at 24 h exposure against Aedes albopictus (concentration 100 µg/mL) and 48 h (concentration of 50 and 100 µg/mL), while the highest mortality (100%) was observed for Culex quinquefasciatus at 24 h and 48 h at concentration of 100 µg/mL. The 24 h mosquito larvicidal activity of the rhizome oil against Ae. albopictus were LC50 = 25.51 µg/mL; LC90 = 40.22 µg/mL and towards Cx. quinquefasciatus with LC50 = 50.11 µg/mL and LC90 = 71.53 µg/mL). However, the 48 h larvicidal activity were LC50 = 20.03 µg/mL and LC90 = 24.51 µg/mL (Ae. albopictus), as well as LC50 = 36.18 µg/mL and LC90 = 55.11 µg/mL (Cx. quinquefasciatus). On the other hand, no appreciable mortality and larvicidal activity was observed for the leaf oil. The larvicidal activity of the essential oils of Z. collinsii was being reported for the first time.

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.

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%.

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 constituents of essential oils from the leaves, stems, roots and fruits of Alpinia polyantha.

The essential oils obtained from the leaves, stems, roots and fruits of Alpinia polyantha D. Fang (Zingiberaceae) have been studied. The leaf oil was comprised mainly of camphor (16.1%), α-pinene (15.2%) and ß-agarofuran (12.9%), while the major constituents of the stem oil were α-pinene (12.4%), ß-cubebene (10.6%), ß-agarofuran (10.3%) and globulol (8.8%). However, ß-cubebene (12.6%), fenchyl acetate (10.8%), ß-maaliene (9.0%), aristolone (8.8%) and α-pinene (8.2%) were the compounds occurring in higher amounts in the root oil. The quantitatively significant compounds of the fruit oil were δ-cadinene (10.9%), ß-caryophyllene (9.1%), ß-pinene (8.7%) and α-muurolene (7.7%).

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.

Chemical composition and larvicidal activity of essential oils from Zingiber montanum (J. Koenig) Link ex. A. Dietr. against three mosquito vectors / Composición química y actividad larvicida de aceites esenciales de Zingiber montanum (J. Koenig) Link ex. A. Dietr. contra tres vectores de mosquitos

The chemical composition and larvicidal activity of essential oils derived from the leaves and rhizomes of Zingiber montanum (J. Koenig) Link ex. A. Dietr. were reported. The main compounds in the leaf oil were ß-pinene (13.8%), ß-phellandrene (11.3%) and α-pinene (7.3%) while the rhizome oil was dominated by sabinene (41.1%), terpinen-4-ol (22.7%) and (E)-nerolidol (14.3%). The minimum lethal concentration (larvicidal activity) LC50of the rhizome oil at 24 h against Aedes albopictus was 35.17 µg/mL, while LC50 values of 32.20 µg/mL and 31.12 µg/mL were obtained against Aedes aegypti and Culex quinquefasciatus respectively. At 48 h the oil displayed larvicidal action with LC50 values of 23.18 µg/mL, 25.58 µg/mL and 18.99 µg/mL respectively towards Ae. albopictus, Ae. Aegyptiand Cx. quinquefasciatus. The leaf oil did not exhibit significant mortality and larvicidal action. The results indicate the potential of rhizome essential oil of Z. montanumas a source of larvicidal agent.

En el presente trabajo se reportan la composición química y actividad larvicida de los aceites esenciales obtenidos de hojas y rizomas de Zingiber montanum (J. Koenig) Link ex. A. Dietr. Los principales compuestos en el aceite de hojas fueron ß-pineno (13.8%), ß-felandrene (11.3%) y α-pineno (7.3%); mientras que los más abundantes en el aceite de rizomas fueron sabineno (41.1%), terpinen-4-ol (22.7%) y (E)-nerolidol (14.3%). La concentración letal mínima (actividad larvicida) LC50 del aceite de riomas ante Aedes albopictus fue 35.17 µg/mL, mientras que los valores de LC50 de 32.20 µg/mL y 31.12 µg/mL fueron obtenidos ante Aedes aegyptiy Culex quinquefasciatus respectivamente. A las 48 horas, el aceite mostró acción larvicida con valores de LC50 de 23.18 µg/mL, 25.58 µg/mL y 18.99 µg/mL respectivamente, ante Ae. albopictus, Ae. Aegyptiand Cx. quinquefasciatus. El aceite de hojas no mostró mortalidad ni acción larvicida significativa. Los resultados indican el potencial del aceite esencial de rizomas de Z. montanum como una fuente de agentes larvicidas.

Novel 3-substituted-2-oxoindoline-based N-hydroxypropenamides as histone deacetylase inhibitors and antitumor agents.

Histone deacetylases (HDAC) are currently a group of validated targets for anticancer drug discovery and development. In our research program to find novel small molecules targeting these enzymes, we designed and synthesized two series of 3-hydroxyimino-2-oxoindoline- and 3- methoxyimino-2-oxoindoline-based N-hydroxypropenamides (3a-g, 6a-g). The results show that these propenamides potently inhibited HDAC2 with IC50 values in sub-micromolar range, approximately 10-fold lower than that of SAHA (also known as suberoylanilohydroxamic acid). Evaluation of cytotoxicity of these compounds in three human cancer cell lines revealed that most of the synthesized compounds were up to 5-fold more cytotoxic than SAHA. Docking studies showed that the compounds bound to HDAC2 at the binding site with higher binding affinities compared to SAHA. Our present results demonstrate that these novel 3-substituted-2-oxoindoline-based N-hydroxypropenamides are potential for further development as anticancer agents.

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.

A comparative analysis of essential oils of Goniothalamus macrocalyx Ban., Goniothalamus albiflorus Ban. and Goniothalamus tamirensis Pierre ex Fin. & Gagnep. from Vietnam.

Essential oils hydrodistilled from the leaves and stem barks of Goniothalamus macrocalyx Ban., Goniothalamus albiflorus Ban. and Goniothalamus tamirensis Pierre ex Fin. & Gagnep. growing in Vietnam were analysed by gas chromatography (GC) and GC-coupled with mass spectrometry. α-Pinene (1.7-50.0%), ß-pinene (tr-6.8%), ß-myrcene (tr-1.5%), (E)-ß-ocimene (tr-4.6%), ß-caryophyllene (9.9-12.8%), aromadendrene (0.2-6.0%), α-humulene (1.7-6.9%), α-cadinol (1.2-14.5%), δ-cadinene (0.1-10.3%) and n-hexadecanoic acid (0.2-1.9%) were common to the oil samples. α-Pinene (50.0%) was the most abundant single constituent of the leaf oil of G. macrocalyx, whereas the major compounds of the stem were α-cadinol (14.5%), ß-caryophyllene (10.3%) and octadecanoic acid (8.2%). Benzoic acid (18.4%), ß-caryophyllene (12.4%) and α-pinene (10.3%) were present in the leaf of G. albiflorus, whereas limonene (21.2%), ß-caryophyllene (12.8%) and α-phellandrene (9.3%) were identified in the stem. The leaf oil of G. tamirensis was characterised by abundance of α-pinene (33.4%), viridiflorol (18.5%) and ß-caryophyllene (12.4%), whereas γ-gurjunene (11.2%), ß-caryophyllene (10.9%) and δ-cadinene (10.3%) predominates in the stem oil.

Essential oil compositions of Alphonsea philastreana (Pierre) Pierre ex Finet & Gagnep. and Alphonsea gaudichaudiana (Baill.) Finet & Gagnep. from Vietnam.

Essential oils isolated from the air-dried leaves of Alphonsea philastreana and Alphonsea gaudichaudiana growing in Vietnam have been studied for their constituents by means of gas chromatography with flame ionization detector and gas chromatography coupled with mass spectrometry. Sesquiterpenes were the most prominent class of compound identified in the oils. The quantitatively significant constituents of the oils were (E)-ß-ocimene (6.9% and 8.5%), bicycloelemene (8.9% and 6.3%), ß-caryophyllene (5.1% and 5.9%), α-humulene (5.8% and 4.6%), bicyclogermacrene (9.3% and 6.3%), guaiol (9.0% and 5.2%) and α-eudesmol (8.3% and 5.5%), respectively, for A. philastreana and A. gaudichaudiana. This is the first comprehensive report on the volatile oil constituents of the studied species.

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.