Evaluation of essential oils by gas-chromatography and a new method: "electronic nose"

The 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.


New trends in selection of poppy (Papaver somniferum L.)

Since the isolation of morphine by Sertümer in 1805 more than 40 alkaloids have been isolated from the poppy (Papaver somniferum L.). Some of them have high biological-pharmacological activity and economical importance, while others have none, or restricted ones. The increasing demand for poppy alkaloids is the consequence of the widening of the medical application of morphine and its related compounds: the quantity of morphine used for the treatment of pain reached a record level of 17.9 tonnes in 1997, compared with an annual average of 2.2 tonnes used during the period 1978-1983. However, the production of raw material (either opium, or dried capsule is produced) has to be re-evaluated taking into consideration the UN Convention signed in 1988 against Illicit Traffic in Narcotic Drugs and Psychotropic Substances. The countries were forced by the Convention to introduce new arrangements in poppy production including selection and introduction of new cultivars.

In the present work up to date results of poppy selection are reviewed explaining the biosynthetic and eco-physiological background of their alkaloid accumulation. The effectiveness and the possibilities of traditional selection methods as well as the probability of the application of biotransformation for producing cultivars accumulating low or high alkaloid content or plant material with special alkaloid spectrum (codeine, thebaine, narcotine) are discussed. The examples of Hungarian cultivars 'Monaco', 'Kék Gemona' and 'Tebona' are given in more detail.


Comparative evaluation of different valerian (Valeriana officinalis L.) lines

Research project to establish a Hungarian valerian cultivar with acceptable production, biological and chemical properties of five promising Valeriana officinalis L. lines were studied. The populations were not homogeneous especially with regard to leaf shape and colour. Line 'IV/1' showed the strongest vigour, was characterised by the highest root-yield (381.79 g/plant), volatile-oil (0.60 m1/100 g) and valtrat content (1.15%). However, the highest valeric-acid content (0.20%) was measured in another line, 'I/5'. According to our results, the above-mentioned lines (1/5', 'IV/1') could be the basic material of breeding work in the future.

Changes in germination ability during genebank storage at some medicinal plant seeds belonging to the Solanaceae family

In the present work we have examined the changes of germination ability of some medicinal plant species belonging to the Solanaceae family (Datura stramonium L., Datura innoxia Mill. and Hyoscyamus niger L.) during 5-6 years' storage period. According to our results, all the three species showed an after-ripening behavior. Potassium nitrate and gibberellic acid increased significantly the rate of germination in the case of Datura species. During the storage period tested (1995-2001), the species maintained their germination ability which is favourably but not significantly influenced by the cooled gene bank conditions. The degree of ripeness affected considerably the proportion of germinated seeds at all the three species. As a consequence of our results we emphasise that propagation with completely ripe seeds is proposed, however, half-ripe seeds developped in an unadvantageous vegetation period can be also utilized in the practice. The effect of vegetation year on stramony seeds manifested in the length of after-ripening period, while in the case of henbane the germination ability was also influenced.

Identification of plant taxons by isoelectric focusing

Differences were demonstrated in esterasei coenzyme pattern of some essential oil producing plants belonging to the Apiaceae family — fennel (Foeniculum vulgare Mill.), angelica (Angelica archangelica L.), lovage (Levisticum officinale Koch.), dill (Anethum graveolens L.), coriander (Coriandrum sativum L.), anise (Pimpinella anisum L.), caraway (Carum carvi L.) — as well as differences between two varieties of fennel seed by using isoelectric focusing. That method provides quality control in essential oil plants and is suitable to describe isoenzyme pattern characteristic for taxons.

Based on our findings, isoelectric focusing seems to be suitable for identification and differentiation of different plant samples, providing an easy tool for further processing as well as for breeding.

Our further aim is to apply that method to differentiate among samples belonging to the same species according to their value of inner content.


Volatile constituents of Nepeta cataria L., N. glechoma Benth. and N. parviflora M. Bieb. from Hungary

In 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.


Legal harmonization of the Hungarian horticulture conditioned by the accession

In the EU-horticulture is treated with special care. As far as its regulation is concerned, different orders are in force to single branches. The regulation of the branch of medicinal plants is related chiefly to the processing, because the overwhelming part of the basic material is to be imported. More preoccupation falls to the ornamental plant branch, although both the production and the turnover are controlled by the market. Irrespective of this fact, the quality standards are high. Also the production and the sale relations are carefully circumscribed, with special regard to the processing procedures. In the control of the quality an important role devolves on the producers' organizations, likely in our country on the so-called TESZ-es (Cooperatives for production and sale). In this regard the domestic prescriptions took much over of the EU practices.

The structure of sales in vegetable and fruit branches is continously changing, the demands of the consumers are more and more satisfied by the super- and hypermarkets. Their marketing organizations offer almost the half of the total of quantity commodities. In consent with the processing industry they raise quite severe requirements to producers. These requirements are to be taken into account also among our circumstances. There is a similar situation valid in the viticulture and winery. Within these branches we are able to compete on good chances of adapting our regulations to those of the EU. In this area there falls also responsibility to our vine-growing communities. Particulary a watch must be kept over the reputation of our renown quality wines and the results already achieved must be protected.

The competent ministries — at first the Ministry of Agriculture and Rural Development — has already shown great flexibility to the desires in regard to the expectable legal harmonization. The legislative, registrative and controlling activities are to be continued in this mentality.


Evaluation of the quality of Sorbus fruits belonging to different species

The interest in wild growing fruits was increased considerably by the pharmaceutical industry, the cosmetics as well as by the food industry. (Stefanovits-Bányai et al., 2004). Elderberry (Sambucus nigra L), sand thorn (Hippophae rhamnoides L.), cornet (Cornus mas L.), dog rose (Rosa canina L. bearing hips) and the Sorbus species (Sorhus ssp.) have been well known medicinal and/or ornamental plants since long. Recently, precious substances have been detected in their fruits, which are indispensable in healthy foods. Several species and micro-species of the genus Sorbus are components of the native flora of Hungary, and the fruit of some of them have been consumed traditionally, however, they are preferably considered as ornamentals. The nursery of Alsótekeres (Balatonvilágos) maintained some 16 clones of Sorbus species, which are mainly apomictic "micro species" of. the collection. In 2003, a comprehensive analysis of sorb fruits born on apomictic micro species was initiated in order to find those, which will be suitable to establish plantations. It turned out that considerable differences exist between the fruits of individual taxa, however, it is largely influenced by seasonal effects. According to physical measurements, a scale of mean fruit masses could be established. As for chemical ingredients of the fruits, those are of special interest, which are involved mainly in anti-oxidant activities of the organisms (calcium, potash, phosphorus, copper, magnesium).

Studies on the alkaloid production of genetically transformed and non-transformed cultures of Lobelia inflata L.

The investigations of the growth and alkaloid production of cell suspension-, callus-, organized- and hairy root cultures from Lobelia inflata L. proved that these cultures are able to synthesize the characteristic piperidine alkaloids of the intact plant. Alkaloid precursor amino acids (Phe, Lys) and plant growth regulators affect not only the growth and differentiation of tissue cultures but also their secondary metabolism. The synthetic regulator Sz/I I combined with Phe increased the total alkaloid content considerably in callus- and organized cultures; regulator Sz/28 especially increased the lobeline content (in organized cultures in response to Lys, in callus tissues as a result of Phe application). With the aim of optimizing growth and alkaloid production of the genetically transformed hairy root cultures of Lobelia inflata L. we studied the effect of some growth regulators (NAA, IAA, kinetin) and precursor amino acids (Lys, Phe). The kinetin had inhibiting effect on the growth and lobeline production of the hairy roots. The IAA and NAA increased the biomass formation and lobeline production. The highest lobeline level was detected in tissues cultivated on hormone-free medium containing Phe.


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