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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:
J. Szarka
,
O. Toldi
,
E. Szarka
,
J. Remenyik
, and
et al.

The fact that production is often unsuccessful even when resistant varieties are selected on the basis of the hypersensitive reaction can be attributed to the lack of adequate knowledge on plant disease resistance. In addition to specific plant responses to pathogen species, plants also possess an aspecific defense reaction which, instead of causing rapid tissue destruction, is based on the opposite strategy, protecting the plant against attack by microbes through tissue compaction achieved by cell enlargement and cell division. Genetic analyses carried out in pepper revealed that the general defense reaction was inherited as a monogenic recessive trait (gds). Pathophysiological observations indicate that the stimulus threshold is lower and the reaction rate faster than for specific defense reactions. Biochemical analyses suggest that, unlike plants exhibiting rapid tissue destruction, plants containing the gds gene do not require an oxidative burst elicited by hydrogen peroxide to stimulate the defense mechanism. It was also found that the regulation of the general defense system involves metabolic pathways that are independent of salicylic acid. The general and specific plant reactions form an integrated system of plant defense.

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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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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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Summary

Qualitative and quantitative analysis was performed on supercritical-fluid and conventional Soxhlet extracts of Betula pendula Roth., Alnus glutinosa (L.) Gaertn., and Platanus hybrida Brot. bark. The effect of the two extraction methods on extraction yields was compared. Lupeol and β-sitosterol were identified in the bark extracts by TLC and by GC-MS. The main components were betulin and lupeol followed by β-sitosterol; betulinic acid seemed to be a minor constituent. Betulin content was determined by RP-HPLC, with acetonitrile-water 80:20 (v/v) as mobile phase. Comparison of the extraction methods showed that supercritical-fluid (scCO2 + EtOH) and ethanolic Soxhlet extraction resulted in the highest extraction yields. Accumulation of betulin derivatives was higher in supercritical-fluid extracts (scCO2 + EtOH) than in conventional Soxhlet extracts.

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