A.K. Pant

Terpenoid compositions, and antioxidant and antimicrobial properties of the rhizome essential oils of different Hedychium species.

A phytochemical study of the rhizome essential oils of four different Hedychium species was performed by means of GC and GC/MS analyses. H. ellipticum mainly contained 1,8‐cineole, sabinene, and terpin‐4‐ol, while H. aurantiacum possessed terpin‐4‐ol, para‐cymene, and bornyl acetate as the major entities. Similarly, trans‐meta‐mentha‐2,8‐diene and linalool were noticed in H. coronarium. Three different collections (I–III) of H. spicatum showed amazing differences in the relative contents of their essential oils, 1,8‐cineole and 10‐epi‐γ‐eudesmol being identified as markers for samples I and II, terpin‐4‐ol and sabinene being the major compounds in sample III. The rhizome essential oils of the above species were studied for their antioxidant activities by different methods, including their effect on the chelating properties of Fe2+, DPPH radical‐scavenging activity, and reducing power. Antimicrobial screenings of the oils by the paper‐disc method were performed against Staphylococcus aureus, Shigella flexneri, Pasteurella multocida, Escherichia coli, and Salmonella enterica enterica, and the respective minimum‐inhibitory‐concentration (MIC) values were determined. The rhizome essential oils from all Hedychium species exhibited moderate‐to‐good Fe2+ chelating activity. H. spicatum from collection site III showed a completely different DPPH radical‐scavenging profile than the samples from the other collection sites.

Phytoecdysteroids from Ajuga macrosperma var. breviflora roots.

Three new phytoecdysteroids, ajugacetalsterones C (1) and D (3) and breviflorasterone (2), were isolated from the roots of Ajuga macrosperma var. breviflora along with five known compounds, namely, 20-hydroxyecdysone, cyasterone, makisterone A, 20-hydroxyecdysone 3-acetate, and 20-hydroxyecdysone 2-acetate. The structures of 1-3 were elucidated on the basis of extensive 1D and 2D NMR spectroscopic studies. The new compounds possess acetal oxygen bridges between C-26 and C-20/C-22, or C-26/C-23, or a lactone bridge between C-26 and C-23.

Essential Oil from Hyptis suaveolens Poit.

ABSTRACT The essential oil obtained from the aerial parts of Hyptis suaveolens Poit collected in the Kumaun Region of India was found (by GC/MS) to differ chemically from that reported from chemotypes collected in South America and Malaysia. The main components of this Indian oil were sabinene (41.0%), β-pinene (9.8%), β-caryophyllene (7.9%), and limonene (6.8%), accompanied by more than 50 other compounds including (Z)-α-trans-bergamotol (2.0%), caryophyllene oxide (5.8%), ar-abietatriene (4.4%), and ar-abietatrienol (0.4%).

Volatile constituents of rhizomes and leaves of Alpinia allughas roscoe

Abstract The GC and GC/MS analyses of the oils from the rhizome and leaves of Alpinia allughas led to identification of 22 and 42 constituents, respectively. The major constituents of the rhizome oil were β-pinene (55.3%) and α-pinene (9.7%) whereas in the leaf oil β-pinene (25.5%), 1,8-cineole(23.3%) and α-humulene (9.7%) were major. The unique feature is the dominant presence of two pinenes (rhizome (65%) and leaf (30.9%)) unlike other species of Alpinia.

Volatile Constituents of Alpinia calcarata Rosc.

Abstract The essential oil composition of the rhizome and leaf oil of Alpinia calcarata Rosc. of Indian origin has been analyzed by combination of capillary GC and GC/MS. In all, 31 constituents were identified in rhizome oil and 28 constituents in leaf oil. 1,8-Cineole (41.4% and 42.2%) was found to be the major constituent in the leaf and rhizome oil, respectively.

Rhizome Essential Oil of Hedychium aurantiacum (Zingiberaceae), A Potential Source of (+)-Linalool

ABSTRACT The essential oil from rhizomes of H. aurantiacum Roscoe (Zingiberaceae) was found to consist largely of (+)-linalool (80.6%) and monoterpene hydrocarbons (16.0%). The composition of the oil differs markedly from the rhizome essential oil obtained from H. spicatum var. acuminatum (H. acuminatum Roscoe), a plant which closely resembles H. aurantiacum.

Chemical composition and antibacterial activity of rhizome oils from Hedychium coronarium Koenig and Hedychium spicatum Buch-Ham.

Abstract The essential oil obtained from rhizomes of Hedychium coronarium Koenig and Hedychium spicatum Buch-Ham. growing wildly in Kumaun region of central Himalaya were analysed by GC and GC-MS. Forty six compounds representing 98.7 % of H. coronarium oil were identified. The main components identified were linalool (29.3 %), limonene (20.3 %), trans-meta-mentha,2,8diene (12.9 %), γ-terpinene (8.9 %) and 10-epi-γ-eudismol (3.8 %).Thirty six compounds accounting 87.4 % of H. spicatum oil were identified.The major constituents were 1,8-cineole (17.6 %), α-eudesmol (17 %), 10-epi-γ-eudismol (9.7%), δ-cadinene (7.5 %), cubenol (6.9 %), germacrene D-4–01 (6.8 %) and γ-cadinene (5.4 %). H. coronarium oil was rich in monoterpene hydrocarbons while H. spicatum oil was rich in suquiterpene alcohols. Both the oils showed antibacterial activity against five pathogenic bacteria, viz. Escherichia coli, Staphylococcus aureus, Salmonella typhi, Pseudomonas aeruoginosa and Proteus vulgaris.

Linalool-rich essential oil from the rhizomes of Zingiber roseum Rosc

Abstract The combination of GC and GC/MS analysis of the essential oil obtained from the rhizome of Zingiber roseum Rosc. revealed the presence of over 44 compounds of which 36 compounds have been identifed comprising 94.9% of the oil. The oil was found to be rich in linalool (53.3%) with lesser amounts of limonene (14.0%), β-pinene (9.3%) and α-pinene (4.4%) being among the other constituents. The marker components of the family Zingiberaceae such as borneol (0.9%) and β-eudesmol (1.4%) were found to be present in relatively low concentrations in the oil. This is the frst report on composition of the oil from rhizome of Z. roseum.

Constituents of Zingiber chrysanthum Rosc. Root Oil

ABSTRACT Twenty-four components, mainly monoterpenes with the major constituents 1, 8-cineole (42%), α-fenchyl acetate (15%), α-terpineol (6%) and camphene (6%), of the essential oil from roots of Zingiber chrysanthum, growing wildly in India, were identified by means of GC, GC/MS and GC-FTIR.

Essential oil composition and antioxidant activity of leaves and flowers of Skimmia anquetilia N.P. Taylor & Airy Shaw

The essential oils of the leaves and flowers of Skimmia anquetilia N.P.Taylor & Airy Shaw (family: Rutaceae) were examined by the combination of gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The analysis of the oils from leaves and flowers revealed the presence of β-phellandrene (1.8%, 18.4%), geijerene (2.0%, 15.0%), germacrene B (11.6%, 2.0%), linalyl acetate (7.3%, 11.2%), linalool (9.5%, 9.4%), α-terpineol (5.6%, 4.4%) and pregeijerene (0.2%, 5.6%) as major constituents. The antioxidant activity of the leaf and flower oils was studied and compared by different methods including their effect on reducing power, chelating properties of Fe+2 and in vitro 2’2’-diphenylpicrylhadrazyl (DPPH) radical-scavenging activity. The total phenolic contents in the water extracts of leaf and flower were estimated and compared.