Multiple myeloma (MM) belongs to hematological cancers and its incidence is increasing worldwide. Despite recent advances in its therapy, MM still causes many deaths every year. In fact, current therapies sometimes fail and are associated with severe adverse effects, including neurotoxicity. As a part of our ongoing efforts to discover new potential therapies against MM, we prepared Hibiscus sabdariffa extracts obtained by a microwave-assisted solvent extraction and investigate their activity by in vitro assays on the RPMI-8226 cell line. The bioguided fractionation of the crude ethanolic extract allowed the identification of HsFC as the most effective extract. We assessed cell viability (MTT and Tripan blue test), cell migration (Boyden chamber assay), and neurotoxicity (DRG neurotoxicity assay). The promising results prompted us to further fractionate HsFC and we obtained two molecules effective against RPMI-8226 cells without neurotoxic effects at their active concentrations. Moreover, both compounds are able to significantly reduce cell migration.

BackgroundBreast cancer is the most frequent tumor in women. Natural substances represent an important source of innovative therapeutic solutions, eventually integrating or substituting conventional drugs and chemicals. Hibiscus sabdariffa L. is a plant of the Malvaceae family that has raised interest thanks to its anti-inflammatory, antioxidant and anticancer effects. In this work, we evaluated the antitumoral effects of an enriched fraction of Hibiscus sabdariffa L. extract (HsEF) in two human breast cancer cell lines, MCF-7(ERα +) and MDA-MB-231 (triple negative).

Multiple Myeloma (MM) is an aggressive tumor causing millions of deaths every year and currently available therapies are often unsuccessful or correlated with severe side effects. In our previous work we demonstrated that the Hibiscus sabdariffa hydroalcoholic extract inhibits the growth of the MM cell line and we isolated two metabolites responsible for the activity: Hib-ester and Hib-carbaldehyde. Herein we report their interaction with proteasome, one of the main targets in the fight against MM. The molecular modelling study outlined a good interaction of both compounds with the target and these results prompted us to investigate their potential to inhibit proteasome. Metabolites were then isolated from the calyces and an extract with a high content of Hib-ester and Hib-carbaldehyde was prepared. An anticancer profile was drawn, evaluating apoptosis, autophagy and proteasome inhibition, with the anticancer properties being mainly attributed to the Hib-ester and Hib-carbaldehyde, while the proteasome inhibition of the extract could also be ascribed to the presence of anthocyanins, a class of secondary metabolites already known for their proteasome inhibitory activity.

Mertensia maritima is a commercially interesting herb with edible leaves and flowers, characterized by oyster flavor and taste. Plant propagation and traditional cultivation are challenging for this species. Therefore, the main purpose of the present study was to establish successful protocols aimed at ensuring oyster plant shoot propagation, rooting and in vivo acclimatization. Both micropropagation and rooting were tested, comparing the traditional in vitro solid substrate in jar vs. the liquid culture in a temporary immersion system (TIS) bioreactor (Plantform™). A Murashige and Skoog (MS) medium added with 4-μM thidiazuron (TDZ) and 1-μM α-naphthaleneacetic acid (NAA) was employed for micropropagation, while a half-strength MS medium supplemented with 4-μM indole−3-butyric acid (IBA) was used for rooting. Different acclimatization conditions in the greenhouse or in growth chamber were tested. Morphometric and microscopical analyses were performed on the oyster plant leaves at the propagation, rooting and acclimatization stages both in a jar and in a TIS. Micropropagation in a TIS allowed to obtain large shoots, while a great number of shoots was observed in the jar. M. maritima shoots rooted in TIS produced more developed roots, leaves with more developed waxy glands and well-formed stomata; moreover, the plants coming from the TIS showed the best acclimatization performances.

Agastache aurantiaca ‘Sunset Yellow’ and A. mexicana ‘Sangria’ are aromatic plants with edible flowers characterized with good flavors, nutritional values and pleasant aromas. The aim of this study was to establish a successful protocol to ensure fast shoot propagation, rooting and in vivo acclimatization to obtain many vigorous plants for edible flower production. Micropropagation was tested with an agarized Murashige and Skoog (MS) medium enriched with different 6-benzylamino purine (BAP) levels. In vitro rooting trials were carried out using a half-strength MS medium comparing the traditional jar method with an agarized medium and the temporary immersion system (TIS) bioreactor with a liquid medium. After acclimatization in a greenhouse, the survival of plants and their development were recorded. Microscopical analyses were performed on both in-jar and in-TIS leaves at rooting stages and compared with in vivo leaves. In both species, the greatest number of new shoots was noted at 2.22 µM and 3.33 µM of BAP. In TIS, rooting started earlier, resulting in larger plants with more roots and longer roots than in the jar substrate. Any anatomical difference was observed in leaves collected from the jar and TIS during the rooting stage. The best acclimatization performances were recorded in plants coming from the TIS bioreactor.

Sweet basil (Ocimum basilicum L.) is one of the most well-known aromatic herbs, which are economically important for food and pharmaceutical purposes. In vitro regeneration protocols are a fundamental part of molecular approaches, such as genome editing, which are used to enhance crop quality and pathogen resistance. In this research, in vitro regeneration methods were developed to examine the morphogenic aptitude of four different explant types from five commercial cvs of Ocimum basilicum L. (‘Prospera’, ‘Paoletto’, ‘Italiko FT’, ‘Dark opal’, and ‘Bolloso napoletano’). ‘Prospera’ showed the highest direct regeneration efficiency in all of the explant types (100% in the roots, 36% ± 0.02 in the cotyledons, 7.5% ± 0.2 in the hypocotyls, and 50% ± 0.04 in the cotyledonary nodes). The roots were found to be the most effective explant type, producing nodule-like meristems (100% in ‘Prospera’ and ‘FT Italiko’, 95.24% ± 0.01 in ‘Bolloso napoletano’), as precursors of shoots. Histological analysis was confirmed to be a suitable method to detect meristematic activity during the early morphogenic process and to evaluate the explants’ regeneration potential.