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The main colouring substance and essential oil components of different carrot varieties
46-49.Views:181Investigating colouring components it was found that the p carotene being the most important from the point of view of nutrition constitutes about 60-70% of the total colouring material, whereas the ratio of a carotene is 18-34%.
Among the varieties having a short growing season the common incidence rate of the a and 13 carotene is very high (92.49 %), even a lower total colouring material content (178.02 ppm) results in bright orange red carrot roots.
The incidence of a and carotene represents, however, only 84.24% of the similar total colouring material value (171.74 ppm) measured in Nantais.
Among the storage varieties Fertődi vörös has the highest value of total colouring substance (213.04 ppm) from which the common proportion of the two carotene (a and (3) compounds amounts to 93.77%.
When testing the essential oil components the cariophyllen shows the highest incidence rate, which has a negative influence on the flavour materials of the carrot. Among the early varieties in Nantais Forto this quantity amounts to 24.08 ppm which is almost twice as much as the amount measured in Nantais. We found a similarly unfavourable quantity in %lords &ids (25.47 ppm).
Looking at the beta-pinen and 1-limonen of a bactericidal effect the quantity of l-limonen is higher (1.36 ppm on the average of the varieties). Among the varieties that have a longer growing season and which are suitable for processing Fertődi vörös is the best in terms of essential oil and colour content. Its beta-pinen content was above the average of this variety (1.12 ppm) while its 1-limonen content was considerably high (1.26 ppm).
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Evaluation of essential oils by gas-chromatography and a new method: "electronic nose"
85-89.Views:175The chemical quality of the essential oils is determined by their composition as well as by the complex aroma features. For the evaluation of odour and aroma, sensory tests are practised, especially for applications such as aromatherapy, food industry or perfumery. In the recent studies we investigated eight Mentha origins (populations of Mentha iperita, M. spicata and M. arvensis) of our genebank collection using a new and effective instrumental sensory evaluation method parallelly with the usual GC analysis.
The results show that the examined mint clones possess different essential oil accumulation levels and special flavour characteristics, too. The GC analysis of the essential oil revealed characteristic differences at both inter- and intraspecific level in the proportion of mentol, menthon, carvon, limonene, menthyl acetate and in two not identified monoterpenes.
In the sensory tests the special complex aroma enables a reliable distinction with a single exception among the populations by the help of the "electronic nose" equipment. The distinction among the samples based on the sensor signals of the instrument — evaluated by multivariate methods — shows a close relation with the detected monoterpene components of the essential oil.
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Comparative study of three rosemary (Rosmarinus officinalis L.) clones during the growing season
67-72.Views:196The growth rate of three rosemary clones, `Harmat', 'Salem' and `Horvát', their essential oil content and its components as well as the total phenol content and total antioxidant capacity in their aqueous and ethanolic extracts were compaired. Total phenol content (determined by Folin-Ciocalteau reagent) and antioxidant power (FRAP-value) of aqueous and ethanolic rosemary extracts were measured by spectrophotometric method. The essential oil content was determined from drug by water-steam distillation. `Harmat' showed the most intensive growth through the vegetation period. The total antioxidant power of the ethanolic extracts from all the three clones was similar: a decrease was observed at the end of the season. In most cases more antioxidant compounds were dissolved in the aqueous extracts. The total quantity of phenolic compounds shows a good correlation with the potential extent of stress effects. The difference among the phenol contents of the various clones can be derived from the difference in their tolerance, because phenols have antioxidant effects contributing to protection against harmful impacts. Difference between the two extraction methods (aqueous and ethanolic) is due to the distinct solubility of compounds. Some other components, like essential oil compounds also possess antioxidant effect and in this way they may influence the antioxidant power of extracts.
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Volatile constituents of Nepeta cataria L., N. glechoma Benth. and N. parviflora M. Bieb. from Hungary
47-50.Views:128In the temperate zone live about 150 species of the Nepeta genus. Our investigations covered the examinations of the volatile oil containing species of the genus endemic in Hungary, Nepeta cataria and Nepeta parviflora. Latter is a relict of the ancient steppe-flora and endemic in Hungary as well. Phytochemical examination of the volatile oil containing plant material has also been carried out. Catnip growing in the Botanical Garden of PTE Department of Botany contained 0,67% volatile oil in May and 0,14% in November. Chemical character of the volatile oils were measured by gas chromatography/mass spectrometry and citronellol, citral-A, citral-B and geraniol components were identified. The composition of the oil of November samples shifted towards citronellol (65%). In both samples insecticide and repellent activity bearing compounds (+)-cis-p-menthane-3,8-diol, and (—)-trans-p-menthane-3,8-diol in 2-2.5 and 4-4.5% amount have been found. The catnip sample deriving from Germany contained a small amount of anetol, citronellol, neral, geraniol and geranial (6-13%), and possibly two isomers of nepetalactone in 23-31%.
The Nepeta parviflora endemic in the Nagyvolgy valley near Nagykaracsony consisted of the same compounds in the investigated years (1998-2000). Its limonene, methyl chavicol, b-cariophyllene, b-selinene, b-cubebene, davanone, germacrene-D constituents have been identified. In the year 2000 different GC % of these compounds were detected in the different organs of the plants.
The closely related species Nepeta cataria var. citriodora contained 83% citral, and the N. glechoma (= Glechoma hederacea) contained 41% a-cubebene, 20% patchoulenol, 7,7% spathulenol respectively. These compounds were identified by gas chromatography and gas chromatography / mass spectrometry.
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Changes of the characteristics of Satureja hortensis L. herb during flowering period
56-60.Views:145In this study the changes of the characteristics of Satureja hortensis herb were investigated during flowering period, in case of savories of 4 different origins. The change of drying ratio, leaf/stem ratio, essential oil content, the ratio of several essential oil components (carvacrol, y-terpinene, p-cymol, a-pinene, p-pinene and fi-caryophyllene) were studied from bud formation till seed ripening.
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Yield and composition of supercritical fluid extracts of different Lamiaceae herbs: Satureja hortensis L., Ocimum basilicum L. and Melissa officinalis L.
75-79.Views:210In our work the effectiveness of supercritical carbon dioxide extraction was studied on volatile and nonvolatile components of Lamiaceae herbs. The aim of our investigations was to determine the optimal extraction parameters yielding high amount of volatiles and nonvolatiles in a desirable composition. As plant materials, dried and powdered cude drugs of Satureja hortensis, Ocimum basilicum and Melissa officinalis were chosen. Pressure (8-50 MPa), temperature (35-60 °C), time (5-60 min) and the ratio of modifier (5-50% methanol) of extraction were regulated. Results obtained by supercritical fluid extraction (SFE) were compared to that of the conventional extraction procedure, hydrodistillation (HD). In the case of Satureja hortensis, Ocimum basilicum and Melissa officinalis extract yield of SFE was comparable to the essential oil amount obtained by hydrodistillation from the same drug. Essential oil rich extracts were analysed by GC-FID, while extracts rich in nonvolatile compounds were analysed by HPLC. We have found that yield and quality of SFE extracts highly depend on the conditions of extraction.
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Yield and composition of supercritical fluid extracts of different Lamiaceae herbs
79-82.Views:211In our work the effectiveness of supercritical carbon dioxide extraction was studied on volatile components of Lamiaceae herbs. The aim of our investigations was to determine the optimal extraction parameters yielding high amount of volatiles in a desirable composition. As plant materials, dried and powdered cude drugs of Thymus vulgaris, Thymus pannonicus, Satureja hortensis, Ocimum basilicum, Rosmarinus officnalis and Salvia officinalis were chosen. Pressure (8-30 MPa), temperature (35-60 °C) and time (5-60 min) of extraction were regulated. Results obtained by supercritical fluid extraction (SFE) were compared to that of the conventional extraction procedur, hydrodistillation (HD). In the case of Thymus vulgaris, Thymus pannonicus and Salvia officnalis, extract yield of SFE was comparable to the essential oil amount obtained by hydrodistillation from the same drug. Essential oil rich thyme extracts were analysed by GC-FID. We have found that yield and quality of SFE extracts highly depend on the conditions of extraction.
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Evaluation of supercritical plant extracts on volatile and non volatile biologically active lipophil components
78-83.Views:158Authors dealt more than ten years with the analysis of supercritical extracts. For extraction (SFE) carbon dioxide was used as supercritical solvent. Fractionation of extracts was carried out by releasing the separations pressure at two stages. The extracts were collected as separate samples successively in time.
The traditional extractions were carried out with steam distillation or by using n-hexane and ethanol in Soxhlet apparatus. For the analysis of volatile compounds GC, GC-MS; of non volatile compounds TLC-densitometry and spectroscopic methods were used.
The following general characteristics were established comparing the composition of steam distillated oils with that of volatile SFE fractions. The SFE fractions were richer in monoterpene-esters and poorer in alcohols than the essential oils prepared by traditional way (clary sage, lavandel). Regarding the distributi,n of the monoterpene and sesquiterpene compounds, the SFE fractions contained sesquiterpene hydrocarbon in higher percentage than the distillated oils (e.g. 13-caryophyllene in Salvia fruticosa, (3-caryophyllene, ymuurolene, y-cadinene in Ochnum basilicum). Further the proportion of sesquiterpenes increased in SFE fractions collected successively in time.Significant difference was remarkable in respect of the optical rotationability of lovage oil and SFE fraction which was probably caused by the different ratio between the two ligustilid enantiomers. It was verified in some cases that a part of mono- and sesquiterpenes were present originally in a bounded form (glycosides) in plants. Therefore they appeared in essential oil fractions only after previous acidic treatment (Thymus, Origanum species). During the supercritical extraction the azulenogene sesquiterpene lactones did not transform to azulenes (in chamomile, yarrow), but the non volatile SFE fractions of some Asteraceae plant contained sesquiterpene--lacton of unchanged structure in high quantity (e.g. cnicin in blessed thistle, parthenolide in feverfew). Authors obtained also SFE fractions which were rich in triterpenoids and phytosterols (marigold, common dandelion).