Effects of Phytogenically Synthesized Bimetallic Ag/ZnO Nanomaterials and Nitrogen-Based Fertilizers on Biochemical and Yield Attributes of Two Wheat Varieties

Wheat is the most important staple food worldwide, but wheat cultivation faces challenges from high food demand. Fertilizers are already in use to cope with the demand; however, more unconventional techniques may be required to enhance the efficiency of wheat cultivation. Nanotechnology offers one potential technique for improving plant growth and production by providing stimulating agents to the crop. In this study, plant-derived Ag/ZnO nanomaterials were characterized using UV-Vis spectroscopy, SEM, EDX, FTIR, and XRD methods. Various concentrations of phytogenically synthesized Ag/ZnO nanomaterials (20, 40, 60, and 80 ppm) and nitrogen-based fertilizers (urea and ammonium sulphate 50 and 100 mg/L) were applied to wheat varieties (Galaxy-13 and Pak-13). The results obtained from this research showed that application of 60 ppm Ag/ZnO nanomaterials with nitrogenous fertilizers (50 and 100 mg/L) were more effective in improving biochemistry and increasing yield of wheat plants by reducing enzymatic and non-enzymatic antioxidants (proline content, soluble sugar content, malondialdehyde, total phenolic content, total flavonoid content, superoxide dismutase, peroxidase, and catalase); and significantly increasing the protein content, number of grains per pot, spike length, 100-grain weight, grain yield per pot, and harvest index of both wheat varieties, compared to untreated plants. These findings allow us to propose Ag/ZnO nanomaterial formulation as a promising growth- and productivity-improvement strategy for wheat cultivation.

Ehsan, Maria; Iqbal Raja, Naveed; Mashwani, Zia Ur Rehman; Zohra, Efat; Abasi, Fozia; Ikram, Muhammad; Mustafa, Nilofar; Hamid Wattoo, Feroza; Procków, Jarosław; Pérez de Lastra, José Manuel.

Nanomaterials, 12(17), 2894 : 1-23 (2022)
DOIDigital.CSIC

Efficient Oral Priming of Tenebrio molitor Larvae Using Heat-Inactivated Microorganisms

Microbial resistance is a global health problem that will increase over time. Advances in insect antimicrobial peptides (AMPs) offer a powerful new approach to combat antimicrobial resistance. Invertebrates represent a rich group of animals for the discovery of new antimicrobial agents due to their high diversity and the presence of adaptive immunity or “immune priming”. Here, we report a priming approach for Tenebrio molitor that simulates natural infection via the oral route. This oral administration has the advantage of minimizing the stress caused by conventional priming techniques and could be a viable method for mealworm immunity studies. When using inactivated microorganisms for oral priming, our results showed an increased survival of T. molitor larvae after exposure to various pathogens. This finding was consistent with the induction of antimicrobial activity in the hemolymph of primed larvae. Interestingly, the hemolymph of larvae orally primed with Escherichia coli showed constitutive activity against Staphylococcus aureus and heterologous activity for other Gram-negative bacteria, such as Salmonella enterica. The priming of T. molitor is generally performed via injection of the microorganism. To our knowledge, this is the first report describing the oral administration of heat-inactivated microorganisms for priming mealworms. This technique has the advantage of reducing the stress that occurs with the conventional methods for priming vertebrates.

González-Acosta, Sergio; Baca-González, Victoria; Asensio-Calavia, Patricia; Otazo-Pérez, Andrea; López, Manuel R.; Morales-delaNuez, Antonio; Pérez de Lastra, José Manuel.

Vaccines, 10(8), 1296 : 1-11 (2022)
DOIDigital.CSIC

Modulation of Popocatépetl’s activity by regional and worldwide earthquakes

Volcanoes switching from quiescence to eruption shortly after catastrophic earthquakes have raised interest for volcanic triggering and the influence of earthquakes on volcanic activity. Its influence on already active systems and especially at open-vent volcanoes is more difficult to apprehend. A number of recent observations suggest an influence of tectonic earthquakes on Popocatépetl’s activity, the importance of which remains unknown. To further investigate this, we introduce an index, based on the near-field concept, identifying the earthquakes with the highest potential to promote volcanic activity (hereafter termed “significant earthquakes”). The time series of significant earthquakes is compared with the intensity of the volcanic activity, as characterized by the number and energy of volcano-tectonic earthquakes, the number of dome extrusions, the intensity of thermal and degassing fluxes, and ash production. Three main periods with contrasting activity stand out showing that Popocatépetl presents intense activity when significant tectonic earthquakes are frequent. Enhanced extrusion apparently follows significant earthquakes quickly with pulses of dome extrusion that peak after 1.3 ± 0.3 years. Conversely, extrusive activity vanishes when significant seismicity disappears, as during the period 2003–2011, which coincides with a 12-year-long significant seismicity gap. Hence, we propose that the 1994–2022 open-vent activity at Popocatépetl is in part modulated by the repetitive occurrence of significant earthquakes that periodically promote volcanic activity.

Boulesteix, Thomas; Legrand, Denis;Taquet, Noémie; Coppola, Diego; Laiolo, Marco; Valade, Sébastien; Massimetti, Francesco; Caballero-Jiménez, Gema; Campion, Robin.

Bulletin of Volcanology, 84 (2022)
DOIDigital.CSIC

Solid-Supported Tetrahydropyran-Based Hybrid Dipeptide Catalysts for Michael Addition of Aldehydes to Nitrostyrenes

The heterogenization of homogeneous catalysts onto a solid support is a step towards a more sustainable chemistry. The recovery and reuse of catalysts is extremely important from a practical, economic and environmental point of view. In this regards, we report a series of polymer-supported tetrahydropyran-based hybrid dipeptides that serve as active catalysts for the enantioselective Michael addition of aldehydes to β-nitrostyrenes. These supported catalysts have been designed considering the optimal anchor position and orientation between the catalyst and the solid support. Additionally, the influence of the linker length on the catalytic efficiency was studied. The catalysts allowed the transformation of a variety of substrates in 76–98% yield and with 94–97% enantiomeric excess. Detailed deactivation studies have provided important information, which allows to increase the useful life of these immobilized catalysts.

García-Monzón, Irma; Borges-González, Jorge; Martín, Tomás

Advanced Synthesis & Catalysis 2022, 364
DOIDigital.CSIC

Shortest Enantioselective Total Syntheses of (+)-Isolaurepinnacin and (+)-Neoisoprelaurefucin

The shortest enantioselective total syntheses of (+)-isolaurepinnacin and (+)-neoisoprelaurefucin have been accomplished. These syntheses were based on a common parallel synthetic strategy using Prins–Peterson cyclization in their core construction. In only one step, a seven-membered ring oxacycle with the correct cis-stereochemistry ring closure and the Δ4 position of the endocyclic double bond in (+)-isolaurepinnacin was obtained. This unsaturation was also necessary to accede to the bromodioxabicycle on (+)-neoisoprelaurefucin.

Sinka, Victoria; Cruz, Daniel A.; Martín, Víctor S.; Padrón, Juan I.

Organic Letters 2022, 24, 29, 5271–5275
DOIDigital.CSIC

Chemistry of Hydrogen Peroxide Formation and Elimination in Mammalian Cells, and Its Role in Various Pathologies

Hydrogen peroxide (H2O2) is a compound involved in some mammalian reactions and processes. It modulates and signals the redox metabolism of cells by acting as a messenger together with hydrogen sulfide (H2S) and the nitric oxide radical (•NO), activating specific oxidations that determine the metabolic response. The reaction triggered determines cell survival or apoptosis, depending on which downstream metabolic pathways are activated. There are several ways to produce H2O2 in cells, and cellular systems tightly control its concentration. At the cellular level, the accumulation of hydrogen peroxide can trigger inflammation and even apoptosis, and when its concentration in the blood reaches toxic levels, it can lead to bioenergetic failure. This review summarizes existing research from a chemical perspective on the role of H2O2 in various enzymatic pathways and how this biochemistry leads to physiological or pathological responses.

Curieses Andrés, Celia María; Pérez de Lastra, José Manuel; Andrés Juan, Celia; Plou Gasca, Francisco José; Pérez-Lebeña, Eduardo.

Stresses, 2 (3) : 256-274 (2022)
DOIDigital.CSIC

Antimicrobial Activity of Cathelicidin-Derived Peptide from the Iberian Mole Talpa occidentalis

The immune systems of all vertebrates contain cathelicidins, a family of antimicrobial peptides. Cathelicidins are a type of innate immune effector that have a number of biological functions, including a well-known direct antibacterial action and immunomodulatory function. In search of new templates for antimicrobial peptide discovery, we have identified and characterized the cathelicidin of the small mammal Talpa occidentalis. We describe the heterogeneity of cathelicidin in the order Eulipotyphla in relation to the Iberian mole and predict its antibacterial activity using bioinformatics tools. In an effort to correlate these findings, we derived the putative active peptide and performed in vitro hemolysis and antimicrobial activity assays, confirming that Iberian mole cathelicidins are antimicrobial. Our results showed that the Iberian mole putative peptide, named To-KL37 (KLFGKVGNLLQKGWQKIKNIGRRIKDFFRNIRPMQEA) has antibacterial and antifungal activity. Understanding the antimicrobial defense of insectivores may help scientists prevent the spread of pathogens to humans. We hope that this study can also provide new, effective antibacterial peptides for future drug development.

Otazo-Pérez, Andrea; Asensio-Calavia, Patricia; González-Acosta, Sergio; Baca-González, Victoria; López, Manuel R; Morales-De la Nuez, Antonio; Pérez de la Lastra, José Manuel.

Vaccines 10(7): 1105(2022)
DOIDigital.CSIC

Cellular landscaping of cisplatin resistance in cervical cancer

Cervical cancer (CC) caused by human papillomavirus (HPV) is one of the largest causes of malignancies in women worldwide. Cisplatin is one of the widely used drugs for the treatment of CC is rendered ineffective owing to drug resistance. This review highlights the cause of resistance and the mechanism of cisplatin resistance cells in CC to develop therapeutic ventures and strategies that could be utilized to overcome the aforementioned issue. These strategies would include the application of nanocarries, miRNA, CRIPSR/Cas system, and chemotherapeutics in synergy with cisplatin to not only overcome the issues of drug resistance but also enhance its anti-cancer efficiency. Moreover, we have also discussed the signaling network of cisplatin resistance cells in CC that would provide insights to develop therapeutic target sites and inhibitors. Furthermore, we have discussed the role of CC metabolism on cisplatin resistance cells and the physical and biological factors affecting the tumor microenvironments.

Bhattacharjeea, Rahul; Deya, Tanima; Kumar, Lamha; Kar, Sulagna; Sarkar, Ritayan; Ghorai, Mimosa; Malik, Sumira; Kumar Jha, Niraj; Vellingiri, Balachandar; Kumar Kesari, Kavindra; Pérez de Lastra, José Manuel; Dey, Abhijit.

Biomedicine and Pharmacotherapy, 153, 113345: 1-18 (2022)
DOIDigital.CSIC

Differences in the levels of sulphites and pesticide residues in soils and wines and under organic and conventional production methods

The surface and output of organic agriculture is growing steadily in recent years, being generally seen as a healthier, safer and more sustainable alternative to conventional agriculture. Comparisons between organic and conventional products are nonetheless scarce in the literature, especially in the case of wine. The aim of this study was to compare sulphite content and pesticide residues in both soils and wines under organic and conventional production. Fourteen samples of organic and conventional wines and vineyard soils were collected in pairs for each of the seven wine-producing islands of the Canary Islands. A QuEChERS-based method was employed to detect 218 pesticides and 49 POPs. Sulphites were measured by potentiometric titration with a double electrode. On average, higher levels of sulphites were found in conventional wines. Similarly, conventional wines presented higher numbers and concentrations of pesticide residues both in soils and wines than their organic counterparts. The overall pesticide concentrations in our sample was 4.2 µg/kg. Conventional wines presented a considerably higher average concentration than organic wines (8.2 against 0.25 µg/kg). In turn, concentrations in conventional soils averaged 8.7 against 2.8 µg/kg in organic soils, a 68.19 % lower residue concentration. The analytes most commonly found were PCB 28, p,p′-DDE, tebuconazole and the metabolite 4,4′-dichlorobenzophenone in soils and mefenoxam, tebuconazole, fluopyram and boscalid in wines. No single wine exceeded the 10 % of the MRLs established by the European Union for wine grapes. However, the presence of low levels of pesticides in organic wines should be monitored.

Alonso-González, Pablo; Parga-Dans, Eva ; Acosta Dacal, Andrea Carolina; Zumbado Peña, Manuel; Pérez Luzardo, Octavio.

Journal of Food Composition and Analysis, 112, 104714 : 1-8 (2022)
DOIDigital.CSIC

Aseismic Fault Slip During a Shallow Normal-Faulting Seismic Swarm Constrained Using a Physically Informed Geodetic Inversion Method

Improved imaging of the spatio-temporal growth of fault slip is crucial for understanding the driving mechanisms of earthquakes and faulting. This is especially critical to properly evaluate the evolution of seismic swarms and earthquake precursory phenomena. Fault slip inversion is an ill-posed problem and hence regularization is required to obtain stable and interpretable solutions. An analysis of compiled finite fault slip models shows that slip distributions can be approximated with a generic elliptical shape, particularly well for M ≤ 7.5 events. Therefore, we introduce a new physically informed regularization to constrain the spatial pattern of slip distribution. Our approach adapts a crack model derived from mechanical laboratory experiments and allows for complex slipping patterns by stacking multiple cracks. The new inversion method successfully recovered different simulated time-dependent patterns of slip propagation, that is, crack-like and pulse-like ruptures, directly using wrapped satellite radar interferometry (InSAR) phase observations. We find that the new method reduces model parameter space, and favors simpler interpretable spatio-temporal fault slip distributions. We apply the proposed method to the 2011 March–September normal-faulting seismic swarm at Hawthorne (Nevada, USA), by computing ENVISAT and RADARSAT-2 interferograms to estimate the spatio-temporal evolution of fault slip distribution. The results show that (a) aseismic slip might play a significant role during the initial stage and (b) this shallow seismic swarm had slip rates consistent with those of slow earthquake processes. The proposed method will be useful in retrieving time-dependent fault slip evolution and is expected to be widely applicable to studying fault mechanics, particularly in slow earthquakes.

Jiang, Yu; Samsonov, Sergey V.; González, Pablo J.

Journal of Geophysical Research: Solid Earth, 127(7) : 1-21 (2022)
DOIDigital.CSIC