This paper aims at analysing the synthesis of flavonoids, their import and export in plant cell compartments, as well as their involvement in the response to stress, with particular reference to grapevine (Vitis vinifera L.). A multidrug and toxic compound extrusion (MATE) as well as ABC transporters have been demonstrated in the tonoplast of grape berry, where they perform a flavonoid transport. The involvement of a glutathione S-transferase (GST) gene has also been inferred. Recently, a putative flavonoid carrier, similar to mammalian bilitranslocase (BTL), has been identified in both grape berry skin and pulp. In skin the pattern of BTL expression increases from véraison to harvest, while in the pulp its expression reaches the maximum at the early ripening stage. Moreover, the presence of BTL in vascular bundles suggests its participation in long distance transport of flavonoids. In addition, the presence of a vesicular trafficking in plants responsible for flavonoid transport is discussed. Finally, the involvement of flavonoids in the response to stress is described.

Fruits and vegetables are rich in flavonoids, and ample epidemiological data show that diets rich in fruits and vegetables confer protection against cardiovascular, neurodegenerative and inflammatory diseases, and cancer. However, flavonoid bioavailability is reportedly very low in mammals and the molecular mechanisms of their action are still poorly known. This review focuses on membrane transport of flavonoids, a critical determinant of their bioavailability. Cellular influx and efflux transporters are reviewed for their involvement in the absorption of flavonoids from the gastro-intestinal tract and their subsequent tissue distribution. A focus on the mammalian bilirubin transporter bilitranslocase (TCDB 2.A.65.1.1) provides further insight into flavonoid bioavailability and its relationship with plasma bilirubin (an endogenous antioxidant). The general function of bilitranslocase as a flavonoid membrane transporter is further demonstrated by the occurrence of a plant homologue in organs (petals, berries) where flavonoid biosynthesis is most active. Bilitranslocase appears associated with sub-cellular membrane compartments and operates as a flavonoid membrane transporter.

Flavonoids are a group of secondary metabolites widely distributed in plants that represent a huge portion of the soluble phenolics present in grapevine (Vitis vinifera L.). These compounds play di...

BMAP-28, a bovine antimicrobial peptide of the cathelicidin family, induces membrane permeabilization and death in human tumor cell lines and in activated, but not resting, human lymphocytes. In addition, we found that BMAP-28 causes depolarization of the inner mitochondrial membrane in single cells and in isolated mitochondria. The effect of the peptide was synergistic with that of Ca²⁺ and inhibited by cyclosporine, suggesting that depolarization depends on opening of the mitochondrial permeability transition pore. The occurrence of a permeability transition was investigated on the basis of mitochondrial permeabilization to calcein and cytochrome c release. We show that BMAP-28 permeabilizes mitochondria to entrapped calcein in a cyclosporine-sensitive manner and that it releases cytochrome c in situ. Our results demonstrate that BMAP-28 is an inducer of the mitochondrial permeability transition pore and that its cytotoxic potential depends on its effects on mitochondrial permeability.

The Nutrient Use Efficiency in intensive agriculture is lower than 50% for macronutrients. This feature results in unsustainable financial and environmental costs. Nanofertilizers are a promising application of nanotechnology in agriculture. The use of nanofertilizers in an efficient and safe manner calls for knowledge about the actual effects of nanoproducts on the plant metabolism and eventually on the carrier release kinetics and nutrient accumulation. Hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂) nanoparticles (nHA) have an interesting potential to be used as nanofertilizers. In this study, the effects of different nHA solutions stabilized with carboxymethylcellulose (CMC) were evaluated on germination, seedling growth, and metabolism of Solanum lycopersicum L., used as model species. Our observations showed that the percentage germination of S. lycopersicum is not influenced by increasing concentrations of nHa, while root elongation is strongly stimulated. Tomato plants grown in hydroponics in the presence of nHA have not suffered phytotoxic effects. We conclude that nHA had nontoxic effects on our model plant and therefore it could be used both as a P supplier and carrier of other elements and molecules.

The Green New Deal requires a profound transformation of the agricultural sector, which will have to become more sustainable and ensure universal access to healthy food. Thus, it will be essential to introduce radical technological innovations. Nanotechnologies have the potential to produce a significant boost to the improvement of the food system. Within this context, in the next years, a strong challenge will need to be faced regarding developing new and more efficient uses of nutrients in agriculture, being the nutrient use efficiency (NUE) paramount in sustaining high crop productivity without depleting biodiversity, and altering both the natural and agricultural systems. Nutrients leaching causes environmental pollution and water eutrophication, while nutrient excess favors pest and weed widespread. Therefore, it will be mandatory to improve plant nutrition efficiency without affecting agricultural productivity and economic sustainability. A promising alternative consists of the introduction of the so-called nanomaterial enhanced fertilizers and plant growth stimulators. Such innovation includes nanotechnological solutions that can improve nutrient delivery for a more finely tuned, accurate, and saving-resources distribution of nutrients. This review provides a critical view of the latest advances in nanofertilizer research, mainly referring to nano-hydroxyapatite, silica nanoparticles, and chitosan-derived nanostructures.