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Micropropagation is an important tool in the multiplication of genetically uniform plants that possess desirable traits for horticultural industry. Like many other technologies, it has gone through different stages of evolution that focused mainly on the production efficiency in terms of quantity. However, several problems affecting the quality of the multiplied plants such as shoot tip necrosis, abnormal and inefficient root development, hyperhydration, fasciation and habituation, have not been adequately investigated using additives or modification of growth conditions. Molecular markers can be used to observe genome modifications of the cloned plants but genetic uniformity is not directly related to phenotypic uniformity, therefore molecular markers may not be useful to understand the bases of these undesirable phenomena. In general, although the tissue culture procedure produces quality propagules, the process induces a stress reaction in the developing plantlets. Plants may show a multitude of responses, including epigenetic variations. Epigenetic regulation is not only important for generating differentiated cell types during plant development, but also in maintaining the stability and integrity of their respective gene expression profiles. In plant tissue culture, changes in DNA methylation and in histone modifications have also been reported in many cases during the de-differentiation pathway, ranging from axillary shoot proliferation to protoplast formation. Information on molecular techniques is increasing rapidly together with the decreasing costs of the molecular detection. It is, therefore, important to employ epigenetic markers to understand all desirable or undesirable physiological responses that occur during tissue culture in the production of quality propagules.

Abstract: Genista monosperma Lam. (Leguminosae) is an ornamental shrub cultivated for the production of its attractive flowered branches. In order to overcome the low rate of in vivo propagation, micropropagation protocols and somatic embryogenesis procedures were established. In this work, the effect of ABA treatments on somatic embryo development has been taken into consideration with the aim of improving the conversion of G. monosperma somatic embryos into plants. A statistically significant higher number of regulary torpedo-shaped somatic embryos occurred on modified Murashige and Skoog medium supplemented with 1 μM ABA. When subcultured in light, the embryos induced in the presence of ABA, elongated and converted in a significantly higher percentage than those formed in absence of ABA. Sixty percent of the plantlets were successfully acclimatized in the greenhouse. A sample of the somatic embryo-derived plants were grown in the field, flowered during the third year and were phenotipically normal.

Among natural chemicals used as cancer chemo-preventive and/or chemotherapeutic agents, saponins represent one of the most promising and interesting family of compounds. In this work, we aimed to elucidate the biological effects on human cells of six saponin fractions (SFs) obtained from in vitrocultures of Astragalus verrucosusMoris, a poorly characterized species. Interestingly, SF (3) showed a strongly inhibitory effect on the proliferation of human colon adenocarcinoma cell line (HCT116) via activation of a p53-dependent apoptotic pathway. In addition, SF (3) and the other SFs did not display genotoxic activity in human peripheral lymphocytes.

Bituminaria bituminosa(L.) C.H. Stirt is a perennial species widely distributed in the Mediterranean basin and the Canary Islands. This species is used in folk medicine and currently has considerable pharmaceutical interest for its content in phenylpropanoids, furanocoumarins and pterocarpans. In vitrocultures (shoots and hairy roots) have been performed to obtain plant material useful for the production of these metabolites. Hairy root cultures were successfully established after inoculation of hypocotyls with the LBA 9402 A. rhizogenesstrain. The HRPB3 line was selected for further analysis and elicited with chitosan and salicylic acid. All the HRPB3 cultures showed higher polyphenol content and greater DPPH-antioxidant activity than shoots cultured in vitro. The presence of isoflavone daidzein was detected in the hairy root extracts. The cytotoxic effect of HR extracts has been further tested on HeLa cells: the salicylic acid elicited HR exhibited good antiproliferative effects.

Essential oils and volatile emission from leaves and flowers of three Helichrysumspecies (H. arenarium, H. nudifolium, H. graveolens) were analysed by GC-MS and SPME analysis. A total of 112 components were identified in the EOs representing 92.3–99.9% of the whole oil composition, while 109 constituents were identified in the spontaneous volatile emission accounted for 78.7–98.8% of the total volatile organic compounds (VOCs). Sesquiterpenes represented the main class of constituents in the EOs of the majority studied species. β-caryophyllene was the key compound of H. arenariumand H. nudifoliumleaves, even though (E)-2-hexenal showed high percentage in H. arenariumleaves. H. graveolensEO showed a good amount of diterpenes (cembrene and beyerene), absent in the other species. SPME analyses were carried out for the first time to complete the chemotaxonomic investigation on the volatile organic constituents of these plants.

Essential oils and volatile emission from leaves and flowers of three Helichrysumspecies (H. arenarium, H. nudifolium, H. graveolens) were analysed by GC-MS and SPME analysis. A total of 112 components were identified in the EOs representing 92.3–99.9% of the whole oil composition, while 109 constituents were identified in the spontaneous volatile emission accounted for 78.7–98.8% of the total volatile organic compounds (VOCs). Sesquiterpenes represented the main class of constituents in the EOs of the majority studied species. β-caryophyllene was the key compound of H. arenariumand H. nudifoliumleaves, even though (E)-2-hexenal showed high percentage in H. arenariumleaves. H. graveolensEO showed a good amount of diterpenes (cembrene and beyerene), absent in the other species. SPME analyses were carried out for the first time to complete the chemotaxonomic investigation on the volatile organic constituents of these plants.

The article presents information on the International Symposium on Labiatae which was held in Sanremo, Italy on February 22 to 25, 2006 at the Congress Centre of the Hotel Londra. Several researchers and delegates of private companies from 23 countries attended the symposium. It was structured to emphasize a common link among different issues such as competences in botany, phytochemistry, genetic improvement, biotechnology and agronomy.

Bituminaria bituminosaL. is known for producing several compounds with considerable pharmaceutical interest, such as phenylpropanoids, furanocoumarins and pterocarpans. In vitrocultures of seedlings, shoots, and callus have been produced to obtain plant materials useful for the production of these metabolites. The secondary metabolite profile was evaluated by HPLC-DAD. The extracts of all the in vitromaterial contained the flavonoid daidzein, while plicatin B, erybraedin C and bitucarpin A were found only in the extracts of the in vitroshoots and in wild shoots. The furanocoumarins angelicin and psoralen were found in in vivoand in vitroplants, but in the callus were not detectable. The extracts were also tested for cytotoxic activity in HeLa cell culture; the highest level of cytotoxicity was found in in vitroshoot extracts.

Curcuma longaL. (turmeric) is one of the most important spice and safe food additives. Its main constituents, curcuminoids, showed anti-inflammatory, antitumor and antioxidant effects. In the present work, an in vitropropagation method was developed to achieve selected plant organs with quantified curcuminoid content. In vitroplants were obtained from sprouting buds as primary explants. The major curcuminoid constituents, such as curcumin (CUR), demethoxycurcumin (DEM), and bis-demethoxycurcumin (bis-DEM) were examined in different organs by LC-DAD-ESI-MS. A significant production of curcumin (more than 260 μg g−1fresh weight) was obtained from in vitromicrorhizomes, especially grown in a Murashige and Skoog medium (MS) supplemented with kinetin (0.1 mg L−1), α-naphthaleneacetic acid (NAA, 1 mg L−1), sucrose (6%), agar (5%) and activated charcoal (0.1%). The analyzed microrhizomes showed reduced amounts of DEM and bis-DEM in comparison with CUR levels. In addition a shoot culture line was suitable to biosynthesize curcuminoids, in a ratio very similar to that identified in the fresh rhizomes of parent plants. This study represents the first direct quantification of curcuminoids in turmeric in vitroshoots and microrhizomes to be used in dietary supplements.