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The effect of gamma-irradiation and microwaves on the antioxidant properties of anise, caraway, cumin and fennel essential oils were examined. The essential oils were added individually to sunflower oil after having been exposed to gamma-irradiation at 10 KGy and to microwaves at a low power setting. The data indicated that the treatments did not affect the antioxidant property of the oils. However, essential oils extracted from the gamma-irradiated fruits were more effective as antioxidants than those from microwaved fruits., The antioxidant property of anise, caraway, cumin and fennel essential oils extracted from untreated, [Gamma]-irradiated and microwaved fruits against sunflower oil oxidative rancidity was evaluated. The fruits were exposed to [...]

DC: Am. Chem. Soc. 397 pp. 107a. Patterson RLS, Charlwood BV, MacLeod G, Williams AA, eds. 1992. Bioformation of Flavours. London: R. Soc. Chem. 108. Picataggio ST, Rohrer K, Deanda [...]

Model solutions were used to identify the sorption properties, rates and capabilities of polymeric adsorbents such as XAD-4, XAD-7, XAD-16, Duolite ES-865, Duolite S-761, Porapak-Q and XUS-43436 for ethyl butyrate and octanal. The Freundlich isotherm model was used to assess the sorption of these two major components of aqueous orange essence. In the case of ethyl butyrate, these polymeric adsorbents exhibited quicker sorption rates and greater sorption efficiencies.

The aim of the present study was to evaluate the effects of safranal, an active constituent of the essential oil of Crocus sativus L. stigmas, against pentylenetetrazole (PTZ)-induced status epilepticus.The study was conducted in mice and status epilepticus was induced by administering i.p. 50 mg/kg of phenytoin, followed two hours later by PTZ (100 mg/kg s.c). From the study, it was concluded that safranal produced dose-dependent protection against PTZ-induced status epilepticus and mortality;therefore, it can be considered as useful additional therapy against status epilepticus. Key words: safranal, status epilepticus, seizures, PTZ, essential oil

The aim of this study was to evaluate the chemical composition and biological activity of the oil from the fruits of Galium tricornutum subsp, tricornutum, traditionally used in northern areas of Pakistan for treating microbial infections of skin and throat problems and is locally know as Khoug Jeshay. By GC/ MS analysis, the main components of the hydrodistilled oil were found to be oleic acid, eicosyl ester (12.7%), 9-octadecanoic acid (Z)-, tetradecyl ester (12.3%), hexadecanoic acid (5.6%), 9-octadecanoic acid (Z), 2-hydroxy-I-(hydroxymethyl) ethyl ester (5.5%), hexadecanoic acid, I-(hydroxymethyl)-1,2ethanediyl ester (5.2%), 4H-I-benzopyran-4-one, 2-(3,4-dihydroxyphenyl)-6, 8-di-a'-D-glucopyranosyl-5,7-dihydroxy-(3.6%)myrtenol (2.3%) and 9-octadecanoic acid (Z)-, tetradecyl ester(2%).The oil was tested against six stains of bacteria and showed activity against Escherichia coli.Among five fungal strains, Candida albicans was susceptible to the essential oil with 20% inhibition.The oil showed no cytotoxicity against Artemia salina and a non-significant phytotoxic activity against Lemna minor. Key words: oil composition, Galium tricornutum subsp, tricornutum, oleic acid, eicosyl ester, antifungal, antibacterial, phytotoxicity, cytotoxicity

The essential oils of Artemisia nilagirica (Clarke) Pamp. of the family Asteraceae collected from different altitudes of the Garhwai region were subjected to detailed GC/MS analysis in order to determine the variation of concentration in their constituents. Plants collected from 500 m altitude afforded [alpha]-thujone (36.99%) as a major constituent whereas only a small percentage of [alpha]-thujone was found in the plants collected from two other sites.The 4-nitrobenzonoic acid-4-methoxyphenyl ester (22.12%) was obtained in a high concentration from the plants collected at 1200 m altitude but in the plants from two other altitudes it was found only in small proportion. Similarly, I-linalool (32.47%) was the major constituent of plants at 2000 m altitude but in other plants it was detected in very low concentration. Since the concentration of plant constituents changed from one altitude to another, the medicinal properties of such plants would vary accordingly. Key words: Artemisia nilagirica, Asteraceae, anti-dermatophytic activity, [alpha]-thujone, I-linalool

The chemical composition of the essential oils obtained from fresh leaves and stems of Momordica charantia were analysed by GC and GC/MS.A total of fifteen and eleven compounds representing 61.20% and 79.60% of the leaf and stem essential oils of M. charantia were analysed, respectively.The major constituents in the leaf oil were heneicosane (21.1%), n-decane (5.0%), 1,3,5-cycloheptatriene (4.7%), o-xylene (4.3%), (Z)-9- octadecenamide (4.3%), eicosane (3.9%) and n-hexadecanoic acid (3.5%).The stem oil mainly consisted of heneicosane (18.7%), 8-hexyl pentadecane (16.4%), unknown ([C.sub.18])(9.3%), 1,3,5-cycloheptatriene (7.9%), o-xylene (7.0%), eicosane (6.5%), isothujol (3.5%) and n-hexadecanoic acid (3.3%).The cytotoxicity results gave [LC.sub.50] values of 27.38 for the leaf and 23.74 for the stem essential oils, indicating that both were highly toxic. Key words: Momordica charantia, essential oils, cytotoxicity, chemical composition

Citrus mostruosa is a plant growing wild only on the island of Sardinia. We extracted essential oil from the peel of C. mostruosa fruits at different times of the year. Oil analysis showed unique high percentages of limonene, [alpha]-pinene, myrcene and cis-[beta]-ocimene. Essential oil obtained from fruits harvested in February presented the highest concentrations of these bioactive substances. The peculiar composition of this oil might result in anti-inflammatory and antimicrobial activities. Key words: Citrus mostruosa, essential oil, composition.

The Wittig reaction of benzaldehydes with benzylidenetriphenylphosphoranes passes through a highly nucleophilic polar cycloaddition state. The reactions register positive kinetic isotope effects and Hammet rho values, with and without lithium ions. The stereochemistry of the products is largely unaffected by reactant concentration, the ylide/aldehyde ratio nor by the mode of addition. Lower temperature, on the other hand, favors the formation of cis-products while ortho-position substituents affect the cis/trans ratio. The latter effect is probably due to chelation between the substituent and the ylide phosphorus.

A study of the hydrolysis rates of benzaldehyde O,S acetals clarifies the role of mercury(II) in the process. The second-order rate constants using a variety of Hg(II) halides are uniform except for the least reactive halides, with the reactivity towards the S-ethyl equal to the S-phenyl acetals. The results suggest a mechanism where the reaction rate is not limited by cleavage of the C-S bond, but by ligation of mercury. It shows that mercury(II) does not act as a catalyst but as a reagent and that the degree of reactivity depends much on the degree of complexation of mercury.

The chiral synthesis of 4-alpha-(S)-(arylmethyl)pyroglutamate and of 4-beta-(R)-(arylmethyl)pyroglutamate provides the reactions of interest in the study of the aldol behavior of pyroglutamate-derived enolates and the reactivities of their adducts. Lack of facial bias characterizes the aldol condensation of the enolate with benzaldehyde. The result is in contrast to the hydroxylations and alkylations of the enolates, where the exclusive product is the 4-alpha form.

Problem statement: The fungal infections could be life-threatening in immunocompromised patients. Candida albicans is the most frequent fungi in the oral cavity. Approach: The first step for treatment could be done using topical antifungal agents. Nystatine is a choice for mentioned usage but there are some problems in its using including: unfavorite taste, frequency of usage, etc. Finding better replacements is the subject of many studies. Results: This study was carried out to find an alternative for Nystatine. The study was designed based on laboratory investigations to investigate the antifungal activity of zingiber offcinale (Ginger) on Candida albicans. Candida albicanse (PTCC 5027, ATCC10231) was obtained from Iranian microbial collection and was confirmed by Germ Tube formation test. Ethanolic ginger extract was prepared. The antifungal activity of the extract was determined using Agar dilution and disc diffusion techniques. Data were analyzed by ANOVA test. Conclusion/Recommendations:The results showed that the ethanolic extract was effective on Candida albicans (2 mg [mL.sup.-1]) at the concentration of 1:5. The study indicates that ginger extract might have promise in treatment of oral candidiasis. Key words: Zingiber officinale, antifungal activity, Candida albicans, INTRODUCTION The incidence of serious infections caused by yeast, particularly species of Candida, has increased dramatically during the past decade. Oral candidiasis, formerly dismissed as an simple infection occurring in [...]

Purge-and-trap dynamic headspace/gas chromatography was used to determine release of volatiles in oil emulsion systems containing various fat contents. Fat content in oil emulsions reduced the volatility of added volatile standards. The volatilization of ketones was least affected by fat content. Polar compounds such as aldehydes, alcohols, and ketones were greatly influenced by water.