Detergent Resistant Membrane Domains in Broccoli Plasma Membrane Associated to the Response to Salinity Stress.

Detergent-resistant membranes (DRMs) microdomains, or "raft lipids", are key components of the plasma membrane (PM), being involved in membrane trafficking, signal transduction, cell wall metabolism or endocytosis. Proteins imbibed in these domains play important roles in these cellular functions, but there are few studies concerning DRMs under abiotic stress. In this work, we determine DRMs from the PM of broccoli roots, the lipid and protein content, the vesicles structure, their water osmotic permeability and a proteomic characterization focused mainly in aquaporin isoforms under salinity (80 mM NaCl). Based on biochemical lipid composition, higher fatty acid saturation and enriched sterol content under stress resulted in membranes, which decreased osmotic water permeability with regard to other PM vesicles, but this permeability was maintained under control and saline conditions; this maintenance may be related to a lower amount of total PIP1 and PIP2. Selective aquaporin isoforms related to the stress response such as PIP1;2 and PIP2;7 were found in DRMs and this protein partitioning may act as a mechanism to regulate aquaporins involved in the response to salt stress. Other proteins related to protein synthesis, metabolism and energy were identified in DRMs independently of the treatment, indicating their preference to organize in DMRs.

Plant plasma membrane vesicles interaction with keratinocytes reveals their potential as carriers.

During the last few years, membrane vesicles (as exovesicles) have emerged as potential nanocarriers for therapeutic applications. They are receiving attention due to their proteo-lipid nature, size, biocompatibility and biodegradability. In this work, we investigated the potential use of isolated root plasma membrane vesicles from broccoli plants as nanocarriers. For that, the entrapment efficiency and integrity of the vesicles were determined. Also, the delivery of keratinocytes and penetrability through skin were studied. The results show that the broccoli vesicles had high stability, in relation to their proteins, and high entrapment efficiency. Also, the interaction between the vesicles and keratinocytes was proven by the delivery of an encapsulated fluorescent product into cells and by the detection of plant proteins in the keratinocyte plasma membrane, showing the interactions between the membranes of two species of distinct biological kingdoms. Therefore, these results, together with the capacity of brassica vesicles to cross the skin layers, detected by fluorescent penetration, enable us to propose a type of nanocarrier obtained from natural plant membranes for use in transdermal delivery.

Novel varieties of broccoli for optimal bioactive components under saline stress.

BACKGROUND: Consumption of broccoli is increasing steadily worldwide because of the interest in its bioactive composition and nutritive value for health promotion. Novel broccoli cultivars to be established under current adverse conditions in production areas (aggressive environmental conditions and saline irrigation waters) need to maintain physical and nutritional quality for consumption and year-round supply to the markets. The newly introduced cultivars 'Naxos' and 'Parthenon' have been selected as potential candidates to replace the currently underperforming 'Nubia' variety. We aimed to compare the physical and phytochemical quality (glucosinolates, hydroxycinnamic acids, flavonoids, vitamin C and minerals), as well as the in vitro antioxidant capacity of these three cultivars under conditions of environmental stress. RESULTS: 'Parthenon' showed equal productivity and nutritional composition to 'Nubia', whereas 'Naxos' presented in general the best results when compared to 'Nubia' and 'Parthenon'. For phenolic compounds 'Nubia' presented the highest contents, although 'Naxos' seemed better adapted to saline stress conditions, as suggested by the lowest degree of variation in the contents of healthy phytochemicals, including phenolic compounds, when grown under such conditions. CONCLUSION: 'Naxos' broccoli performed best and is a suitable candidate to replace 'Nubia' for marketable, nutritive and phytochemical quality, especially in areas of production under adverse conditions as found in Mediterranean southeast Spain (semiarid climate with saline irrigation water).

Broccoli-derived by-products--a promising source of bioactive ingredients.

UNLABELLED: The regular dietary intake of broccoli on a weekly basis has been related to better health, but industrial use of broccoli by-products (crop remains) is negligible. Adding value to broccoli by-products in a country such as Spain, one of the main broccoli producers for the EU, is of scientific and economic interest. The present article is focused on the bioactive compounds (glucosinolates, phenolic acids, and flavonoids) and nutrients (vitamin C, minerals, and trace elements), as well as the in vitro radical-scavenging capacity (DPPH. test), of the broccoli products (harvest remains) resulting from greenhouse cultivation using 80 mM NaCl treatment, representative of the currently available irrigation water in the production areas of Murcia (SE Spain). The bioactive compounds and nutrient contents varied according to the cultivar, organ (leaves or stalks), and the saline stress (80 mM NaCl), in the cultivars Marathon, Nubia, and Viola. Cultivar Nubia was not affected dramatically by 80 mM NaCl and the contents of phytochemicals and nutrients in the by-products of Nubia fell within the range of health-promoting levels of edible commercial parts (inflorescences or flower heads). Therefore, adding value to broccoli agrowaste by obtaining bioactive ingredients and nutrients could benefit the food and drug industry. PRACTICAL APPLICATION: Many by-products of the agrifood industry may be useful as sources of nutrients and potentially functional ingredients, giving the opportunity to obtain added-value products. Previous studies have been focused on edible florets, but in this case we are interested in adding value to broccoli by-products that represent a real problem in the production sites because no intended use for this material has been envisaged. Therefore, the aim of this study was to add value to the broccoli-derived by-products, since recycling all this agrowaste to obtain bioactive ingredients for industry can boost profits and reduce costs and environmental problems.