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Oryza sativa L. (Family Poaceae) is cultivated in tropical regions as a staple food all over the world. The rice grain husk is considered as a tonic and administered orally to relieve dysentery. The air-dried seeds husks of O. sativa were exhaustively extracted with methanol in a Soxhlet apparatus. The concentrated methanol extract was adsorbed on silica gel and chromatographed on a silica gel column. The column was eluted with petroleum ether, chloroform and methanol successively to isolate four phytoconstituents characterised as 7-ketostigmasterol (1), 3β-benzyloxy-stigmast-7-one-22-en-19-oic acid 29-ethyleneglycol ether (2), sesquaurs-11-en- 2β, 3β,5α-triol (3) and 2′-(1′′β-hydroxypropyl)-7,4′-dimethoxyapigenin (4). These phytoconstituents were identified on the basis of spectral data analysis.

Two new beta-sitosterol esters have been isolated from the flowers of Punica granatum Linn. (Punicaceae) along with the known compounds n-tricosane (3), n-heptacosanyl n-hexanoate (4), olean-5,12-dien-3beta-ol-28-oic acid (5), and olean-12-en-3beta-ol-28-oic acid (6). The structures of the new phytosterols have been elucidated as stigmast-5-en-3beta-ol-3beta-dodecanoate (beta-sitosterol laurate, 1) and stigmast-5-en-3beta-ol-3beta-tetradecanoate (beta-sitosterol myristate, 2) on the basis of spectral data and chemical analyses.

The chemical composition of the essential oil obtained from dried fruits of Elettaria cardamomum Maton. (Zingiberaceae) of Delhi region was analyzed by gas liquid chromatography (GLC) and gas chromatography mass spectrometry (GC-MS). The variations in essential oil components under different physical factors have been determined. The oil was characterized by a large number monoterpenes (97.6 %) constituting 1,8-cineole (89.6 %), cis-ocimene (3.7 %) and α-terpinene (2.2 %) as the major components. Except the volatile oil exposed to sunlight, 1,8-cineole was detected in all the oil samples and its amount varied from 29.4 % in heated oil to 89.4 % in untreated oil. Linalool, thujyl alcohol, limonene-1,2-epoxide, citronellol, trans-pinocarveol, nerol and linalyl acetate were generated when the oil was heated at 110°C. Exposer of the oil with sunlight, enhanced the production of linalyl acetate (17.8 %) and borneol (12.1 %). 1,4-Cineole, pcymene-8-ol and isoborneol were only detected in UV exposed oil...

The essential oil of the fresh leaves of Eucalyptus citriodora of Delhi region was composed predominantly of 1,8-cineole (45.2%), camphene (30%), α-pinene, linalyl acetate and ledol. When the oil was heated at 110°C for 24 hours, camphene (31.1%), 1,4-Cineole (37.8%), α-pinene (12.4%), veridifloral and 1-terpinene-4-yl acetate were the prominent constituents. Exposure of the oil to the sunlight for 48 hours and UV light for 24 showed percentage variation slightly. Silica gel treat sample exhibited little variation in the chemical composition. Treatment of the oil with alumina neutral decreased the concentration of 1,8-cineole to 0.3% and occurrence of camphene and 1,4-cineole in 36.5 and 39.9 % yields, respectively.