Evaluation of essential oils by gas-chromatography and a new method: "electronic nose"85-89.Views:135
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.
Study of different factors of grapevine regeneration systems and genetic transformation33-36.Views:197
The most limitating factor for successful transformation is the absence of high-yielding regeneration protocols. However, the anther-derived embryogenic culture is an optimal technique for genetic transformation and it has been widely applied in many important cultivars, but the necessity of further development of regeneration systems has been proved. We attempted to produce somatic embryos on a wide range of genotypes from various tissues; leaves, petioles, stem segments. We started the examination of grapevine regeneration via organogenesis, succeeded in inducing shoot from the meristematic tissue of the base of bud by testing induction medium contained different concentrations of two types of hormones. To optimize the conditions of the Agrobacterium-mediated transformation, we studied the effectiveness of different Agrobacterium-treatments, the use of antioxidants and the sufficient quantity of kanamycin for selection of transformed cells.
Sensory analysis as a supporting method for marjoram breeding73-77.Views:178
Marjoram is one of the most important spices in Hungary, which is utilized both in phytotherapy as well as in alimentary industry. Organoleptic quality of the drugs of two Hungarian varieties of Majorana hortensis /'Francia' and 'Magyar'/ were investigated by two different methods of sensory analysis. The chemical composition of the material was checked by GC analysis of the distilled essential oil. Although their main compounds and proportions showed similar patterns, both the human and instrumental sensory tests based on the complex odour and aroma of the drug, proved a significant differentiation of the two varieties.
On the basis of our results, sensory evaluation may be a useful tool in the practice in determination of complex aromatic values of marjoram, as a spice. At the same time it seems to be a suitable method in promotion of breeding efforts.