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  • Author or Editor: É. Lemberkovics x
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The content and composition of active ingredients and essential oils in medicinal and aromatic plants have been studied for several decades. The volatile compounds in essential oils have been analysed routinely using gas chromatography (GC) since 1966, and with GC coupled to mass spectrometric detection (GC/MS) since 1978.The 13 rose varieties selected for chemical analysis varied for colour, shape and fragrance. The static headspace solid phase microextraction (sHS-SPME) technique recently developed for sample preparation and sample enrichment was used to study the volatile aromatic components.The main volatile compound of a sweet-smelling purple rose was found to be phenyl ethyl alcohol (33–52%). The phenyl ethyl alcohol content of fragrant rose flowers with blackish-purple petals increased continuously from early summer to late autumn (from 17 to 70 %). The dominant aromatic components of the yellow, orange and pink rose flowers were hexanol, hexenyl acetate and benzyl alcohol. Phenyl ethyl alcohol and orcinol dimethyl ether were the main constituents of the fragrant pink and white rose varieties. Methyl vinyl anisol and orcinol dimethyl ether were dominant in rose flowers with beige petals. In summary, it can be concluded that the SPME-GC/MS method is suitable for the characterization of rose varieties and for the chemical analysis of aromatic volatile compounds.

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Acta Agronomica Hungarica
Authors:
É. Héthelyi
,
B. Galambosi
,
S. Szarka
,
É. Lemberkovics
, and
É. Szőke

The chemical contents of 47 herb and medicinal plant species cultivated in Finland during 2001–2011 were analysed in Hungary, and a total of 101 components were determined.The phytochemical evaluation of the herbs was aimed at interpretating the effects observed in acclimatization studies performed under Nordic climatic conditions. The phytochemical analysis was successfully applied for the quality control of medicinal, aromatic and culinary herbs, and provided numerous new scientific results (Acorus calamus, Artemisia abrotanum, A. paniculata, Gentiana lutea, Ligusticum scoticum, Perilla frutescens, Rhodiola rosea, Satureja biflora, Tagetes lucida). The results will provide useful guidelines for growers both in Finland and Hungary.

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Certain classes of bioactive compounds can be separated using planar chromatography. Some biological effects (e.g. antibacterial) of these compounds can be investigated directly by examining the growth of a test organism on a specially treated sorbent of thin layer chromatography (TLC). A special method of detection, direct bioautography, is suitable for studying the antimicrobial activity of plant extracts of natural origin by using TLC. Zones of inhibition are visualised by use of a dehydrogenase-activity-detecting, tetrazol-type reagent. Zones of inhibition appeared as pale spots separating well from the dark background. The antibacterial effect of the main essential oil components of some Thymus taxa, as well as that of two antibiotics (streptomycin sulphate and gentamycin) known and applied in practice was investigated against plant pathogenic bacteria. Results showed that thyme essential oil and its components inhibited the growth of test bacteria, but not so considerably as the antibiotics applied. Compositions of the essential oils were analysed by gas chromatography (GC). It could be verified that among the essential oil components, thymol and carvacrol had the strongest inhibitory effect.

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Acta Chromatographica
Authors:
A. Böszörményi
,
Sz. Szarka
,
É. Héthelyi
,
I. Gyurján
,
M. László
,
B. Simándi
,
É. Szőke
, and
É. Lemberkovics

Summary

Our objectives were to establish a GC method capable of quantitative analysis of terpenoids without derivatisation and to examine the amount of β-sitosterol extracted from Morus alba L. leaf and stem bark by use of traditional organic solvent extraction and supercritical-fluid extraction (SFE). To measure β-sitosterol content without derivatization, GC-FID was used with 5-α-cholestan-3-one as internal standard. To identify terpenoid constituents, GC-MS was used; β-sitosterol, phytol, lanost-7-en-3-on, α-amyrin, β-amyrin, and lupeol were identified. We established that for Morus leaf the best SFE method for β-sitosterol was pilot scale SFE; the β-sitosterol content of this extract was higher than that of the hexane solvent extract. Among analytical SFE conditions, 200 bar for 90 min and 300 bar for 60 min resulted in extraction of the most β-sitosterol. For mulberry stem bark, solvent extraction with hexane and SFE at 400 bar and 40°C for 60 min proved the best methods.

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