Capillary GC-ECD and ECNI GCMS characterization of toxaphene residues in primate tissues during a feeding study

The essential oil from different parts of Zingiber roseum plants was extracted by hydrodistillation, and analyzed using enantio-GC, capillary-GC and GC-MS. Two chiral selectors, 6- tert-butyldimethylsilyl-2,3-diethyl-β-cyclodextrin (TBDE-β-CD), and 2,3,6-methyl-β-cyclodextrin (PM-β-CD) doped into 14% cyanopropylphenyl/ 86% dimethylpolysiloxane, and 35% diphenyl/ 65% dimethylpolysiloxane, respectively were compared in order to clarify the stereochemistry and enantioselectivity of terpenoids using chiral gas chromatography. The enantiomeric excess for (1R)-(+)-α-pinene, (1R)-(+)-β-pinene, and (R)-(+)-limonene were characteristic for the rhizome. In TBDE-β-cyclodextrin coated chiral columns, a significant increase in separation factor (a) for β-pinene, limonene, linalool and α-terpineol enantiomers was observed when compared with methyl substituted β-cyclodextrin. The increase in chain length of the alkyl substituents may be the possible cause for enantiomer separation in β-cyclodextrin cavity. In addition, enantioreversal of α-pinene enantiomers in 6-tert-butyldimethylsilyl-2,3-diethyl-β-cyclodextrin was noticed as a unique feature. The enantiomeric compositions of Z. roseum fruit and flower essential oils were similar, but, in contrast, the rhizome oil contained an entirely different composition. Therefore, these results aid in the authentication of the natural origin of Z. roseum essential oils.

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Preparative Capillary GC for Characterization of Five Dracocephalum Essential Oils from Mongolia, and their Mosquito Larvicidal Activity

Natural Product Communications ◽

10.1177/1934578x1601101030 ◽

2016 ◽

Vol 11 (10) ◽

pp. 1934578X1601101

Author(s):

Gülmira Özek ◽

Nurhayat Tabanca ◽

Mohammed M. Radwan ◽

Sanduin Shatar ◽

Altaa Altantsetseg ◽

...

Keyword(s):

Essential Oils ◽

Larvicidal Activity ◽

System Structure ◽

Capillary Gc ◽

Adulticidal Activity ◽

Fraction Collector ◽

First Time ◽

C Nmr

The chemical composition and mosquito larvicidal and adulticidal activity of five essential oils (EOs), Dracocephalum ruyschiana L. (DR), D. foetidum Bunge (DF), D. moldavica L. (DM), D. fruticulosum Steph. ex Willd. (DFr) and D. peregrinum L. (DP) were evaluated. Simultaneous GC-FID and GC-MS analyses revealed in the EOs of DR, DF and DM an unidentified compound (1) ([M+122], 5.4%, 57.9% and 74.0%, respectively). Therefore, we aimed to isolate compound 1 using Preparative Capillary GC (PCGC) connected to a Preparative Fraction Collector (PFC) system. Structure determination of 1 was determined by 1H- and 13C-NMR as p-mentha-1,8-dien-10-al (1, limonen-10-al). Other detected major constituents were thymol (34.0%) and carvacrol (6.1%) in DR; limonene (28.8%) in DF; cis-chrysanthenol acetate (29.1%) and trans-verbenol (5.0%) in DFr; and linalool (17.9%), trans-β-bergamotene (7.9%), (E)-nerolidol (7.7%) and eugenol (5.5%) in DP. The DFr, DP, DR and DM EOs produced 100% mortality to 1st instar larvae of Aedes aegypti L. at 250 ppm and DR and DM EO exhibited the strongest activity and killed 100% 1st instar larvae at 62.5 ppm. No adulticidal activity was observed against female Ae. aegypti. In the scope of the present study, for the first time isolation of limonen-10-al (1) from DR, DM, and DP EOs and larvicidal activity of five Dracocephalum EOs were reported.

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Combination of capillary GC, GC/MS and13C-NMR for the characterization of the rhizome oil ofPiper betleL. (Piperaceae) from Vietnam

Spectroscopy An International Journal ◽

10.1155/1997/397354 ◽

1997 ◽

Vol 13 (2) ◽

pp. 131-136 ◽

Cited By ~ 9

Author(s):

Lê Thanh ◽

Nguyên Xuân Dung ◽

Ange Bighelliand ◽

Joseph Casanova ◽

Piet A. Leclercq

Keyword(s):

Essential Oil ◽

Structure Elucidation ◽

Mass Spectra ◽

Piper Betle ◽

Retention Data ◽

Capillary Gc ◽

Nmr Studies ◽

Identification Techniques ◽

C Nmr

The essential oil from the rhizomes ofPiper betleL. (betel), collected around Hue, was obtained in 0.20% yield. The oil was examined by a combination of capillary GC and GC/MS.13C-NMR studies confirmed the structure assignments proposed by retention data and mass spectra of the components with a content higher than 1%. In some instances the structure elucidation based on GC and GC/MS data had to be corrected. More than forty constituents were found of which the major ones were α-cadinol (26.2%), δ-cadinene (11.7%), and about equal amounts of T-cadinol and T-muurolol (unseparated, together 20.7%). This study clearly illustrates the advantage of complementary identification techniques.

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