Floral biology of medicinal plants II. Lamiaceae species

Several species in the Lamiaceae family are therapeutically significant medicinal plants. Such as sage (Salvia officinalis L.), rosemary (Rosmarinus officinalis L.), peppermint (Moldier piperita L.). marjoram (Majomna hortensis Winch), thyme (Thymus vulgaris L.), Origanum spp., hyssop (Hyssopus officinalis L.), Lavandula spp., basil (Ocimum basalicum L.), lemon-balm (Melissa officinalis L.) are regularly produced in Hungary. Nevertheless, data on their floral biology are not satisfactory. This review intends to gather information on the characteristic constitution of flowers and inflorescences, blooming dynamics, pollination mechanism and crossability of some of the most significant medicinal and spice species

Flowers are mainly hermaphrodite, however, also monoeceous ones are turning up: pistillate flowers marjoram, tyme, oregano. In flowering of a plant individual, a basipetal blooming sequence is described. These species have a floral structure fully adapted to pollination by insects, and the majority of them is an excellent honey-plant (lavandel, hyssop, sage, etc.).

Flowers exhibit characteristic proterandry, therefore autogamy is considered to be almost impossible, and geintonogamy as well as xenogamy to be the most characteristic ways of fertilization. However, in several cases self-fertilization proved to be also successful. Crossability among cultivars or species is depending on the genotype combination and usually produces less seed than the above forms of fertilization.


Yield and composition of supercritical fluid extracts of different Lamiaceae herbs

In 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.