BIOCHEMICAL ANALYSES ON REGENERANTS OF MENTHA PIPERITA L. PROVIDED IN VITRO
MAFTEI DIANA-ELENA 1, NICUŢĂ DANIELA 1, GHIORGHIŢĂ GOGU 1, HĂNCIANU MONICA 2 1. "Vasile Alecsandri" University of Bacau, Faculty of Science, Department of Biology, Marasesti Street, no. 157, Bacau, Romania e-mail: diana.maftei@ub.ro 2. University of Medecine and Pharmacy "Gr.T. Popa" Iasi, Faculty of Pharmacy, Dept. of Pharmacognosy, Romania e-mail: mhancianu@yahoo.com
This present paper is a part of a complex 4-year scientific project – a study on the in vitro reaction, cytogenetical, physiological, and biochemical observations on a series of Labiatae and Asteraceae. The biochemical investigations on peppermint aimed to evince some possible alterations of the quantity or the composition of volatile oils from in vitro regenerants provided on Murashige-Skoog culture medium, and on other variants of MS supplemented with growth regulators. Phytochemical analyses were accomplished on first year regenerants of Mentha piperita. The amount of volatile oil was established by hydrodistillation of dry biomass (100 grams of dry biomass/variant). Volatile oils were submitted to gas-chromatographic analysis combined with mass spectrometry, in order to identify the chemical components within the volatile fractions. The specters were compared to the one from Wiley data system. All the results were related to control – plants provided in vitro on hormone-free MS, and also to the initial biological material, that was the source of explants. The amount of volatile oil within the analysed samples varied between 0.2 and 7.5% of dry biomass, compared to 1.5-3.5%, and 0.5-4% (according to references), [1, 2]. The highest amount of volatile oil was registered within the regenerants provided on hormone-free MS (7% dry matter). Volatile oil’s major components were L-mentol, mentona, eucaliptol, and pulegone. Volatile oil spectrum varied with the medium variant on which the in vitro plants were regenerated. 116 The chemical profile of the essential oils showed that the monoterpens represent between 87.2 and 92.35% (mostly cetons and alcohols), and the sesquiterpens represent between 1.82 and 4.10% (especially hydrocarbonates). There were mostly quantitative differences within the analysed samples, which proves that the method we used to regenerate neoplantlets of Mentha piperita reproduced the initial genotype.