Effects of Deficit Irrigation, Rootstock, and Roasting on the Contents of Fatty Acids, Phytoprostanes, and Phytofurans in Pistachio Kernels

Epoxyalcohol Synthase Branch of Lipoxygenase Cascade

Oxylipins are one of the most important classes of bioregulators, biosynthesized through the oxidative metabolism of unsaturated fatty acids in various aerobic organisms. Oxylipins are bioregulators that maintain homeostasis at the cellular and organismal levels. The most important oxylipins are mammalian eicosanoids and plant octadecanoids. In plants, the main source of oxylipins is the lipoxygenase cascade, the key enzymes of which are nonclassical cytochromes P450 of the CYP74 family, namely allene oxide synthases (AOSs), hydroperoxide lyases (HPLs), and divinyl ether synthases (DESs). The most well-studied plant oxylipins are jasmonates (AOS products) and traumatin and green leaf volatiles (HPL products), whereas other oxylipins remain outside of the focus of researchers' attention. Among them, there is a large group of epoxy hydroxy fatty acids (epoxyalcohols), whose biosynthesis has remained unclear for a long time. In 2008, the first epoxyalcohol synthase of lancelet Branchiostoma floridae, BfEAS (CYP440A1), was discovered. The present review collects data on EASs discovered after BfEAS and enzymes exhibiting EAS activity along with other catalytic activities. This review also presents the results of a study on the evolutionary processes possibly occurring within the P450 superfamily as a whole.

Wheat Oxylipins in Response to Aphids, CO2 and Nitrogen Regimes

Wheat is critical for food security, and is challenged by biotic stresses, chiefly aphids and the viruses they transmit. The objective of this study was to determine whether aphids feeding on wheat could trigger a defensive plant reaction to oxidative stress that involved plant oxylipins. Plants were grown in chambers with a factorial combination of two nitrogen rates (100% N vs. 20% N in Hoagland solution), and two concentrations of CO₂ (400 vs. 700 ppm). The seedlings were challenged with Rhopalosiphum padi or Sitobion avenae for 8 h. Wheat leaves produced phytoprostanes (PhytoPs) of the F₁ series, and three types of phytofurans (PhytoFs): ent-16(RS)-13-epi-ST-Δ¹⁴-9-PhytoF, ent-16(RS)-9-epi-ST-Δ¹⁴-10-PhytoF and ent-9(RS)-12-epi-ST-Δ¹⁰-13-PhytoF. The oxylipin levels varied with aphids, but not with other experimental sources of variation. Both Rhopalosiphum padi and Sitobion avenae reduced the concentrations of ent-16(RS)-13-epi-ST-Δ¹⁴-9-PhytoF and ent-16(RS)-9-epi-ST-Δ¹⁴-10-PhytoF in relation to controls, but had little or no effect on PhytoPs. Our results are consistent with aphids affecting the levels of PUFAs (oxylipin precursors), which decreased the levels of PhytoFs in wheat leaves. Therefore, PhytoFs could be postulated as an early indicator of aphid hosting for this plant species. This is the first report on the quantification of non-enzymatic PhytoFs and PhytoPs in wheat leaves in response to aphids.

A Phytoprostane from Gracilaria longissima Increases Platelet Activation, Platelet Adhesion to Leukocytes and Endothelial Cell Migration by Potential Binding to EP3 Prostaglandin Receptor

Plant phytoprostanes (PhytoPs) are lipid oxidative stress mediators that share structural similarities with mammal prostaglandins (PGs). They have been demonstrated to modulate inflammatory processes mediated by prostaglandins. The present study aims to test the effects of the most abundant oxylipin from Gracilaria longissima, ent-9-D1t-Phytoprostane (9-D1t-PhytoP), on platelet activation and vascular cells as well as clarify possible interactions with platelets and the endothelial EP3 receptor Platelet and monocyte activation was assessed by flow cytometry in the presence of purified 9-D1t-PhytoP. Cell migration was studied using the human Ea.hy926 cell line by performing a scratch wound healing assay. The RNA expression of inflammatory markers was evaluated by RT-PCR under inflammatory conditions. Blind docking consensus was applied to the study of the interactions of selected ligands against the EP3 receptor protein. The 9D1t-PhytoP exerts several pharmacological effects; these include prothrombotic and wound-healing properties. In endothelial cells, 9D1t-PhytP mimics the migration stimulus of PGE₂. Computational analysis revealed that 9D1t-PhytP forms a stable complex with the hydrophobic pocket of the EP3 receptor by interaction with the same residues as misoprostol and prostaglandin E₂ (PGE₂), thus supporting its potential as an EP3 agonist. The potential to form procoagulant platelets and the higher endothelial migration rate of the 9-D1t-PhytoP, together with its capability to interact with PGE₂ main target receptor in platelets suggest herein that this oxylipin could be a strong candidate for pharmaceutical research from a multitarget perspective.

Acute and Rapid Response of Melissa officinalis and Mentha spicata to Saline Reclaimed Water in Terms of Water Relations, Hormones, Amino Acids and Plant Oxylipins

The use of reclaimed water is considered an efficient tool for agricultural irrigation; however, the high salinity associated to this water could compromise plant quality and yields. Balm and spearmint plants were submitted for 15 days to three irrigation treatments in a controlled chamber: control with EC: 1.2 dS m^-1 (control), reclaimed water from secondary effluent (EC: 1.6 dS m^-1) (S) and water from secondary effluent with brine (EC: 4.4 dS m^-1) (SB). The plant water status, stomatal and hormonal regulation, nutritional response, concentration of amino acids and plant oxidative stress-based markers, as well as growth were evaluated. Both species irrigated with saline reclaimed water reduced leaf water potential and gas exchange in comparison with control plants, following 2 days of exposure to irrigation treatments. Nevertheless, spearmint plants recovered photosynthetic activity from the seventh day onwards, maintaining growth. This was attributed to hormonal changes and a greater accumulation of some amino acids and some plant oxylipins (phytoprostanes) in comparison to balm plants, which contributed to the improvement in the organoleptic and health-promoting properties of spearmint. A longer irrigation period with saline reclaimed water would be necessary to assess whether the quality of both species, especially spearmint, could further improve without compromising their growth.

The effect of gamma irradiation, microwaves, and roasting on aflatoxin levels in pistachio kernels

Pistachio is the second largest non-oil export in Iran. The most important problem in pistachio export is its contamination with aflatoxin. Therefore, this study aimed to evaluate the effects of several physical and chemical methods on the qualitative, qualitative and sensory properties of pistachios from Iran as well as the associated residual aflatoxin levels. This study investigated the effects of roasting (temperature 120 °C for 20 and 40 min), gamma radiation (2.5 and 5 KGy), and microwave (1 and 2 min) methods on pistachios and their qualitative characteristics, including moisture, colour, and sensory properties. In addition, aflatoxin B1 and total aflatoxins were artificially added to pistachios to determine the level of aflatoxin remaining after chemical and physical methods. The results showed that the lowest residual level of aflatoxin B1 was related to combined microwave and irradiation methods. Further, the combined methods showed the lowest total aflatoxins residue so the lowest total aflatoxins residue after chemical contamination of 8 μg/kg aflatoxin was related to the combined methods of 5 KGy irradiations with 2 min of the microwave. In addition, the microwaved and irradiated samples did not differ significantly from the control samples in terms of sensory characteristics (P<0.05). It can be concluded that these methods can be successfully applied without adversely affecting the characteristics of pistachios. Considering the position of pistachios in domestic and global markets, these processes can be used to reduce aflatoxins, improve the quality of pistachios, and increase export.

Phytoprostanes from Date Palm Fruit and Byproducts: Five Different Varieties Grown in Two Different Locations As Potential sources

Date palm fruit has been considered for centuries as an ancient nutritional constituent in the human diet. Recently, global trade in dates increased at an average that, simultaneously, will be accompanied by an increase in date palm byproducts. Supported by date phytochemicals and their health benefits, the aim of this work is to evaluate for the first time the presence of special metabolites of plant called phytoprostanes (PhytoPs) in five different varieties of the Phoenix dactylifera L. pulps and pits using a microLC-ESI-QTrap-MS/MS methodology. Results obtained showed the interest of using these matrices as potential sources of several PhytoPs (ent-16-B₁-PhytoP; ent-9-L₁-PhytoP; and epimers of ent-16-F_1t-PhytoP and of 9-F_1t-PhytoP). The variation in concentration between different varieties and different DPF parts was also evaluated. Results obtained will help to unravel the biological activities associated with DPF consumption that could be related to these bioactive metabolites.

Metabolomics-Based Evaluation of Crop Quality Changes as a Consequence of Climate Change

Fruit composition determines the fruit quality and, consequently, consumer acceptance. As fruit quality can be modified by environmental conditions, it will be impacted by future alterations produced by global warming. Therefore, agricultural activities will be influenced by the changes in climatological conditions in cultivable areas, which could have a high socioeconomic impact if fruit production and quality decline. Currently, different stresses are being applied to several cultivated species to evaluate their impact on fruit metabolism and plant performance. With the use of metabolomic tools, these changes can be precisely measured, allowing us to determine changes in the patterns of individual compounds. As these changes depend on both the stress severity and the specific species involved and even on the specific cultivar, individual analysis must be conducted. To date, the most-studied crops have mainly been crops that are widely cultivated and have a high socioeconomic impact. In the near future, with the development of these metabolomic strategies, their implementation will be extended to other species, which will allow the adaptation of cultivation conditions and the development of varieties with high adaptability to climatological changes.

Evaluation of Phoenix dactylifera Edible Parts and Byproducts as Sources of Phytoprostanes and Phytofurans

Even though traditionally date-fruit has been featured by a marginal use, mainly restricted to its dietary intake, in recent years, it has raised the range of applications for this agro-food production. These new uses have entailed an enlarged production of date fruits and, simultaneously, of date palm byproducts. Encouraged by the traditional medicinal uses of dates, according to their phytochemical composition, the present work was focused on the evaluation of a new family of secondary metabolites, the plant oxylipins phytoprostanes (PhytoPs) and phytofurans (PhytoFs), in six separate matrixes of the date palm edible parts and byproducts, applying an UHPLC-ESI-QqQ-MS/MS-based methodology. The evaluation for the first time of date palm edible parts and byproducts as a dietary source of PhytoPs and PhytoFs provides evidence on the value of six different parts (pulp, skin, pits, leaves, clusters, and pollen) regarding their content in these plant oxylipins evidenced by the presence of the PhytoPs, 9-F_1t-PhytoP (201.3-7223.1 ng/100 g dw) and 9-epi-9-F_1t-PhytoP (209.7-7297.4 ng/100 g dw), and the PhytoFs ent-16(RS)-9-epi-ST-Δ¹⁴-10-PhytoF (4.6-191.0 ng/100g dw), and ent-16(RS)-13-epi-ST-Δ¹⁴-9-PhytoF as the most abundant compounds. Regarding the diverse matrixes assessed, pollen, clusters, and leaves for PhytoPs and skins and pollen for PhytoFs were identified as the most interesting sources of these compounds. In this concern, the information obtained upon the detailed characterization performed in the present work will allow unravelling the biological interest of PhytoPs and PhytoFs and the extent to which these compounds could exert valuable biological activities upon in vitro (mechanistic) and in vivo studies, allocating the effort-focus on the chemical species of PhytoPs and PhytoFs responsible for such traits.