Methyl jasmonate (MeJ), an elicitor able to trigger plant defence responses, is a natural and clean alternative to the use of hazardous pesticides. However, the efficient application of MeJ in fields is very limited due to its poor water solubility, thermal stability and phytotoxicity at the high dose required to produce beneficial effects in plants. Here, a novel nanoelicitor (nano-MeJ) was prepared through the functionalization of biocompatible calcium phosphate nanoparticles. The resulting nanocomposite produced a significant increase of beneficial compounds (phytoalexins) in grapes and wines at low MeJ dosage. Indeed, results from in vivo field experiments on Monastrell vineyards (Vitis vinifera L.) revealed that grapes treated with nano-MeJ provided red wines with high content of beneficial stilbenes, similar to the levels obtained with conventional treatments but applying 10 times higher MeJ dosage. We demonstrated that the nanoparticles protect and retain MeJ on the surface of the leaves over long periods of time. This protective action along with the slow release provides a prolonged supply of the resistance-inductor elicitor through the leaves, resulting in a significant efficiency increase. Additionally, the nanocomposite was stable for long periods of time (more than 175 days) and exhibited lower cytotoxicity compared to MeJ, which are important features for its efficient and safe use in agriculture.

Nitrogen composition on grapevines has a direct effect on the quality of wines since it contributes to develop certain volatile compounds and assists in the correct kinetics of alcoholic fermentation. Several strategies can be used to ensure nitrogen content in grapes and one of them could be the use of elicitors such as methyl jasmonate. The use of this elicitor has been proven to be efficient in the production of secondary metabolites which increases the quality of wines, but its use also has some drawbacks such as its low water solubility, high volatility, and its expensive cost. This study observes the impact on the amino acid and ammonium composition of must and wine of Monastrell grapes that have been treated with methyl jasmonate (MeJ) and methyl jasmonate n-doped calcium phosphate nanoparticles (MeJ-ACP). The first objective of this study was to compare the effect of these treatments to determine if the nitrogenous composition of the berries and wines increased. The second aim was to determine if the nanoparticle treatments showed similar effects to conventional treatments so that the ones which are more efficient and sustainable from an agricultural point of view can be selected. The results showed how both treatments increased amino acid composition in grapes and wines during two consecutive seasons and as well as the use of MeJ-ACP showed better results compared to MeJ despite using less quantity (1 mM compared to 10 mM typically). So, this application form of MeJ could be used as an alternative in order to carry out a more efficient and sustainable agriculture.

Self-assembled peptides and proteins have turned out to be excellent templates for the growth of inorganic minerals and can be used to emulate natural biomineralization processes. Doing this, researchers have developed complex sophisticated materials with properties, in some cases, similar to those found in nature. Of special interest is the development of scaffolds able to guide bone regeneration. The bone tissue comprises an organic matrix composed of aligned collagen fibers containing nanoapatite crystals oriented along the fiber direction. During bone mineralization, both processes, the self-assembly of collagen fibrils and mineralization occur simultaneously. Collagen fibers are able to control calcium phosphate nucleation and subsequent apatite crystal growth at a very limited range of collagen density and ionic concentration. In this study, we reproduced the simultaneity of both processes using an artificial peptide fluorenylmethoxycarbonyl-diphenylalanine (Fmoc-FF) that has the ability to self-assemble in water after the addition of Ca²⁺ ions. Therefore, the peptide self-assembly process and the mineralization of apatite are Ca-demanding processes and occur simultaneously. The role of peptide and ionic concentrations has been investigated affording organic/inorganic hybrid hydrogels with different degrees of homogeneity and mineralization. Interestingly, at very low Ca²⁺ concentrations, we found that apatite nanocrystals are integrated into Fmoc-FF fibrils and oriented as in biologically mineralized collagen fibrils, the basic building blocks of bone.

Pancreatic cancer (PC) shows a very poor response to current treatments. Development of drug resistance is one of the causes of the therapy failure, being PARP1 (poly ADP-ribose polymerase 1) a relevant protein in the resistance mechanism. In this work, we have functionalized calcium phosphate-based nanoparticles (NPs) with Olaparib (OLA, a PARP-1 inhibitor) in combination with ascorbic acid (AA), a pro-oxidative agent, to enhance their individual effects. Amorphous Calcium Phosphate (ACP) NPs were synthesized through a biomimetic approach and then functionalized with OLA and AA (NP-ACP-OLA-AA). After evaluation of the loading capacity and release kinetic, cytotoxicity, cell migration, immunofluorescence, and gene expression assays were performed using pancreatic tumor cell lines. In vivo studies were carried out on tumors derived from the PANC-1 line in NOD SCID gamma (NSG) mice. NP-ACP-OLA-AA was loaded with 13%wt of OLA (75% loading efficiency) and 1% of AA, respectively. The resulting dual nanosystem exhibited a gradual release of OLA and AA, being the latter protected from degradation in solution. This ensured the simultaneous availability of OLA and AA for a longer period, at least, during the entire time of in vitro cell experiments (72 hours). In vitro studies indicated that NP-ACP-OLA-AA showed the best cytotoxic effect outperforming that of the free OLA and a higher genotoxicity and apoptosis-mediated cytotoxic effect in human pancreatic ductal adenocarcinoma cell line. Interestingly, the in vivo assays using immunosuppressed mice with PANC-1-induced tumors revealed that NP-ACP-OLA-AA produced a higher tumor volume reduction (59.1%) compared to free OLA (28.3%) and increased the mice survival. Calcium phosphate NPs, a highly biocompatible and biodegradable system, were an ideal vector for the OLA and AA co-treatment in PC, inducing significant therapeutic benefits relative to free OLA, including cytotoxicity, induction of apoptosis, inhibition of cell migration, tumor growth, and survival.

The impact of the morphology, crystalline structure and surface charge of two calcium phosphate phases ( i.e. , amorphous, ACP and apatite, Ap) on their performance and efficiency as elicitor nanocarriers has been investigated in vineyards.

The application of methyl jasmonate (MeJ) as an elicitor to enhance secondary metabolites in grapes and wines has been studied, but there is little information about its use in conjunction with nanotechnology and no information about its effects on wine volatile compounds. This led us to study the impact of nanoparticles doped with MeJ (Nano-MeJ, 1mM MeJ) on the volatile composition of Monastrell wines over three seasons, compared with the application of MeJ in a conventional way (10 mM MeJ). The results showed how both treatments enhanced fruity esters in wines regardless of the vintage year, although the increase was more evident when grapes were less ripe. These treatments also achieved these results in 2019 in the cases of 1-propanol, ß-phenyl-ethanol, and methionol, in 2020 in the cases of hexanol and methionol, and in 2021, but only in the case of hexanol. On the other hand, MeJ treatment also increased the terpene fraction, whereas Nano-MeJ, at the applied concentration, did not increase it in any of the seasons. In summary, although not all families of volatile compounds were increased by Nano-MeJ, the Nano-MeJ treatment generally increased the volatile composition to an extent similar to that obtained with MeJ used in a conventional way, but at a 10 times lower dose. Therefore, the use of nanotechnology could be a good option for improving the quality of wines from an aromatic point of view, while reducing the necessary dosage of agrochemicals, in line with more sustainable agricultural practices.