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Acta Alimentaria
Authors:
É. Szőke
,
E. Máday
,
K. Szentmihályi
,
M. Then
, and
É. Szőke
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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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The emergence time and emergence percentage of four inbred lines with different degrees of chilling tolerance (Mo 17, HMv 5316, HMv 5301, HMv 5478) and the dry mass of young shoots were examined in a seed dressing experiment carried out in pots and sown early under field conditions, on soil infected with pathogens or free of infection (control). The advantage of seed dressing was manifested for all the traits examined, with the exception of emergence time, and the dressing agents were found to exhibit a certain degree of variety specificity. The time to emergence was determined chiefly by the genotype of the inbred lines. Differences were observed when the inbred lines were ranked on the basis of the emergence time and the emergence percentage. This was in agreement with the fact that no correlation was observed between the emergence percentage and the emergence time. Genotype HMv 5316 proved to be best on the basis of emergence time and HMv 5301 for emergence percentage. The poorest results for all the traits examined were recorded for Mo 17, which is in agreement with the poor chilling tolerance of this inbred line. In summary, the following conclusions can be drawn: if the chilling tolerance and growth vigour of the genotypes are to be satisfactorily described, traits characteristic of initial plant development (dry mass of the shoots, size of the leaf area, etc.) should also be considered in addition to the emergence time and emergence percentage.

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Soy is increasingly used as a food additive. In women, it is recommended as an alternative to hormonal replacement therapy and/or a preventive agent against breast cancer and osteoporosis. Previous data revealed that rats fed on raw soybean diet developed pancreas hypertrophy and hyperplasia. An animal model was used in our experiment to examine the effects of raw soybean on parotid gland of rats. The purpose of this study was to light on the role of different neuropeptide-containing nerve fibres on changes in the acinar cells. The morphological structure and the neuropeptide-containing nerve fibers (NPY, GAL, SOM, SP, CGRP, VIP) of the glands were examined by light and electronmicroscopy. Significant increase of the organ weight was detected in the animals fed by raw soybean compared to control samples. Changes in the number of different neuropeptide-containing nerve fibres were various: Significant decrease in the NPY-immunoreactive (IR) and significant increase in the GAL-IR nerve fibres were observed. Slight but not significant increase in VIP-IR; and no changes in the other IR nerve fibres were found. The electronmicroscopic alterations of acinar cells were manifest, where a large number of undifferentiated glandular cells were seen among the acini. Some of these cells contained two nuclei and their cytoplasm contained only a few secretory granules. These granules were similar to those in the mucous cells but not to the serous ones. The results presented here provide direct morphological evidence for the role of raw soy on the density of different neuropeptide-containing nerve fibres inducing proliferation in the acinar cells of parotid glands from rats. It is suggested that the hypertrophic changes in the glands might be caused by the alterations of nerve fibres.

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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 Alimentaria
Authors:
E. Rapavi
,
K. Szentmihályi
,
A. Lugasi
,
E. Vági
,
É. Bányai
,
A. Balázs
,
É. Szőke
, and
A. Blázovics

The different methods of making herbal tea used in various cultures may decrease the efficiency of herbal tea, therefore the purpose of the present study was to examine the changes in antioxidant activity and metal ion concentration in aqueous extracts of “Tieguanyin Stomach Tea” obtained with different steeping times. Partial phytochemical examination, element analysis, and the determination of antioxidant properties were carried out. High Al, Cr, Mn, Ni, Pb and Ti content was observed in the tea drug. Aqueous extracts of the drug sample showed H-donor activity, reducing power and scavenging activity, depending on the steeping time and concentration. According to our findings, 5-min steeping was the least effective and redox parameters of the aqueous extracts did not change considerably between 15 and 120 min of steeping time.

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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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Lake Nasser is one of the largest man-made lakes in the world. The creation of Lake Nasser, due to the impoundment of the River Nile in Southern Egypt, was accompanied by alterations in the environmental conditions that consequently affect the biota. Such alterations lead to corresponding changes in the diversity, abundance and distribution of the phytoplankton community. Therefore, the phytoplankton populations were followed and investigated in Lake Nasser. The phytoplankton community structure revealed a floristical diversity and is composed of various planktonic algal taxa appertaining to the divisions: Chlorophyta, Bacillariophyta (diatoms), Cyanophyta (cyanobacteria), Dinophyta (Dinoflagellates) and Euglenophyta. Chlorophyta contribute more taxa to the phytoplankton than any other groups. However, diatoms and cyanobacteria are numerically the main components and alternate in dominance of the community. Dinoflagellates persist as frequent forms and the euglenoid algae are very scarcely represented. Remarkable spatial (horizontal and vertical) as well as temporal (seasonal) variations are recorded in the distribution of phytoplankton. Pronounced variations in the vertical distribution of the phytoplankton standing crop appear during the periods of thermal stratification (late spring, summer and early autumn). However, diatoms and cyanobacteria remain the most influential groups also in the vertical distribution of the phytoplankton. Water blooms are occasionally observed in limited areas of the southern region of Lake Nasser mainly due to the florishment of the cyanobacterium Microcystis aeruginosa.

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In vitro investigations for the antioxidant and free radical scavenging activity of Myrtilli folium-, Phaseoli fructus sine seminibus- and a drug mixture (Equiseti herba, Myrtilli folium, Phaseoli fructus sine seminibus, Urticae folium) extracts showed antioxidant (LPO inhibitory and chain-breaking antioxidant) activity and free radical (superoxide anion and hydroxyl radical) scavenging effect. The extracts inhibited lipid peroxidation induced enzymatically by adding NADPH and non-enzymatically by adding Fe2+ in brain microsomes and in brain homogenates, respectively. The extracts reduced the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH), which showed chain-breaking antioxidant activity. The extracts scavenged superoxide radicals (O2-·) by inhibiting the reduction of nitro blue tetrazolium evoked by phenazine methosulphate. In addition, the extracts inhibited Fenton-reagent (Fe2+ and H2O2) induced deoxyribose degradation, therefore, it was concluded that the extracts have hydroxyl radical (OH·) scavenging property.

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Solidago canadensis L., (Asteraceae) has been used in European phytotherapy as a urological and antiphlogistical remedy for centuries. The behaviour of dissolution of mineral elements into different tinctures and aqueous extracts obtained from Solidaginis herba was investigated in connection with their quercetin glycoside and organic acid amount. Commonly applied aqueous and alcoholic extracts were analysed for Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, Na, P, Pb, S, Ti, V and Zn content. The concentrations of the minerals examined were determined by inductively coupled plasma emission spectrometry (ICP-OES). Determination of the flavonoids in solidaginis herba and extracts was carried out by a spectrophotometric method, as required by the German Pharmacopoea. For the study of the flavonoid composition of crude drug, the HPLC technique was applied. To determine the relative nutrient contribution of these pharmaceuticals to the diet, data obtained were combined with flavonoid content particulars, then a comparison with U.S Recommended Dietary Allowances (RDA) was made. For evaluation of the phytotherapeutic relevance, k/Na ratio was also calculated. It has been found that the pharmaceuticals examined are important sources of potassium, chromium, manganese, calcium, magnesium, phosphorus and lower sources of iron and zinc, assuming a daily intake of 1-2 l aqueous extracts as recommended for urological diseases. Flavonoid content of the different Solidaginis herba extracts ranged from 62.4 mg l-1 to 305.2 mg l-1.

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