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Recent Submissions

  • Novel Copper Oxide Bio-Nanocrystals to Target Outer Membrane Lectin of Vancomycin-Resistant Enterococcus faecium (VREfm): In Silico, Bioavailability, Antimicrobial, and Anticancer Potential

    Kandeel, Mahmoud; Sharaf, Mohamed; Hamad , Arshad Mahdi; Babalghith, Ahmad O.; Abdalla , Mohnad; Arif , Muhammad; Binsuwaidan , Reem; Attallah , Nashwah G. M.; Aladl , Hossam Aladl Aladl; Selim , Samy; Jaremko, Mariusz (Molecules, MDPI AG, 2022-11-17) [Article]
    In present study, we used Olea europaea leaf extract to biosynthesize in situ Copper Oxide nanocrystals (CuO @OVLe NCs) with powerful antibacterial and anti-cancer capabilities. Physio-chemical analyses, such as UV/Vis, FTIR, XRD, EDX, SEM, and TEM, were applied to characterize CuO @OVLe NCs. The UV/Vis spectrum demonstrated a strong peak at 345 nm. Furthermore, FTIR, XRD, and EDX validated the coating operation’s contact with colloidal CuO @OVLe NCs. According to TEM and SEM analyses, CuO @OVLe NCs exhibited a spherical shape and uniform distribution of size with aggregation, for an average size of ~75 nm. The nanoparticles demonstrated a considerable antibacterial effect against E. faecium bacterial growth, as well as an increased inhibition rate in a dose-dependent manner on the MCF-7, PC3, and HpeG2 cancer cell lines and a decreased inhibition rate on WRL-68. Molecular docking and MD simulation were used to demonstrate the high binding affinity of a ligand (Oleuropein) toward the lectin receptor complex of the outer membrane to vancomycin-resistant E. faecium (VREfm) via amino acids (Leu 195, Thr 288, His 165, and Ser 196). Hence, our results expand the accessibility of OVLe’s bioactive components as a promising natural source for the manufacture of physiologically active components and the creation of green biosynthesis of metal nanocrystals.
  • Increased slow dynamics defines ligandability of BTB domains

    Kharchenko, Vladlena; Linhares, Brian M.; Borregard, Megan; Czaban, Iwona; Grembecka, Jolanta; Jaremko, Mariusz; Cierpicki, Tomasz; Jaremko, Lukasz (Nature Communications, Springer Science and Business Media LLC, 2022-11-16) [Article]
    Efficient determination of protein ligandability, or the propensity to bind small-molecules, would greatly facilitate drug development for novel targets. Ligandability is currently assessed using computational methods that typically consider the static structural properties of putative binding sites or by experimental fragment screening. Here, we evaluate ligandability of conserved BTB domains from the cancer-relevant proteins LRF, KAISO, and MIZ1. Using fragment screening, we discover that MIZ1 binds multiple ligands. However, no ligands are uncovered for the structurally related KAISO or LRF. To understand the principles governing ligand-binding by BTB domains, we perform comprehensive NMR-based dynamics studies and find that only the MIZ1 BTB domain exhibits backbone µs-ms time scale motions. Interestingly, residues with elevated dynamics correspond to the binding site of fragment hits and recently defined HUWE1 interaction site. Our data argue that examining protein dynamics using NMR can contribute to identification of cryptic binding sites, and may support prediction of the ligandability of novel challenging targets.
  • Induction of salt tolerance in Brassica rapa by nitric oxide treatment

    Bano, Atiyyah; Noreen, Zahra; Tabassum, Fariha; Zafar, Fizza; Rashid, Madiha; Aslam, Muhammad; Shah, Anis Ali; Shah, Adnan Noor; Jaremko, Mariusz; Alasmael, Noura Salman; Abdelsalam, Nader R.; Hasan, Mohamed E. (Frontiers in Plant Science, Frontiers Media SA, 2022-11-16) [Article]
    Salinity is one of the major plant abiotic stresses increasing over time worldwide. The most important biological role of nitric oxide (NO) in plants is related to their development and growth under abiotic conditions. The present experiment was conducted to study the effect of salt stress (0 and 100 mM) and NO (0 and 80 μM) on two different ecotypes of $\textit{Brassica rapa}$ (L.): PTWG-HL and PTWG-PK. The different growth attributes, biochemical and physiological parameters, and the mineral contents were examined. The results indicated increased hydrogen peroxide (H$_{2}$O$_{2}$), relative membrane permeability, malondialdehyde (MDA), and Na$^{+}$ content and decreased plant biomass in both ecotypes (PTWG-PK and PTWG-HL) under salt stress. In contrast, NO treatment resulted in increased plant biomass, chlorophyll content, and total soluble proteins and decreased H$_{2}$O$_{2}$, relative membrane permeability, MDA, total phenolic content, catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and Na$^{+}$. The combined effect of salt stress and NO application increased the chlorophyll a content, total phenolic content, and total soluble proteins, but decreased H$_{2}$O$_{2}$, relative membrane permeability, MDA, and Na$^{+}$. The response of carotenoids, anthocyanins, and K$^{+}$, Ca$^{2+}$, and Cl$^{−}$ ions varied in both ecotypes under all treatment conditions. The PTWG-PK ecotype showed maximum overall growth response with the application of NO. Henceforth, it is proposed that the molecular mechanisms associated with NO-induced stress tolerance in plants may be exploited to attain sustainability in agriculture under changing climate scenarios.
  • Bioformulation Containing Cohorts of Ensifer adhaerens MSN12 and Bacillus cereus MEN8 for the Nutrient Enhancement of Cicer arietinum L

    Baliyan, Nitin; Qureshi, Kamal A.; Jaremko, Mariusz; Rajput, Minakshi; Singh, Monika; Dhiman, Sandhya; Maheshwari, Dinesh Kumar; Kant, Chandra; Kumar, Ajay (Plants, MDPI AG, 2022-11-15) [Article]
    Here we examine the effects of different carrier based bioinoculants on the growth, yield and nutritional value of chickpea and on associated soil nutrients. A consortium of two taxonomically distinct endophytic bacteria—Ensifer adhaerens MSN12 and Bacillus cereus MEN8—have promising plant growth promoting (PGP) attributes. We demonstrate their delivery from the laboratory to the field via the formulation of an effective bioinoculant with economic and accessible carriers. Sugarcane straw ash (SCSA) was found to be an efficient carrier and bioformulation for enhancing viability and shelf-life of strains up to 12 months. A bioformulation containing an SCSA-based consortium (MSN12 + MEN8) increased seed germination by 7%, plant weight by 29%, length by 17%, seed-yield by 12%, harvesting index by 14% and proximate nutritional constituents by 20% over consortium treatment without SCSA. In addition, the bioformulation of post-harvest treated soil improved the physico-chemical properties of the soil in comparison to a pre-sowing SCSA-based bioformulation treated crop, being fortified in different proximate nutritional constituents including dry matter (30%), crude protein (45%), crude fiber (35%), and ether extract (40%) in comparison to the control. Principal component analysis and scattered matrix plots showed a positive correlation among the treatments, which also validates improvement in the soil nutrient components and proximate constituents by T6 treatment (MSN12 + MEN8 + SCSA). The above results suggest efficiency of SCSA not only as a carrier material but also to support microbial growth for adequate delivery of lab strains as a substitute for chemi-fertilizers.
  • Rapid lineage diversification of gray mangroves (Avicennia  marina) driven by isolation in cryptic glacial refugia and extreme  environmental conditions in the Arabian Peninsula  

    Friis, Guillermo; Smith, Edward G.; Lovelock, Catherine E.; Ortega, Alejandra; Marshell, Alyssa; Duarte, Carlos M.; Burt, John A. (Authorea, Inc., 2022-11-11) [Preprint]
    Plant systems occurring in ecologically heterogeneous and spatially discontinuous habitats provide an ideal opportunity to investigate the relative roles of neutral and selective factors in driving lineage diversification. Here, we analyzed fully sequenced genomes to study diversification mechanisms in the gray mangroves [Avicennia marina (Forssk.) Vierh.] of Arabia, where they occur at the edge of the species’ range and are subject to variable, often extreme, environmental conditions. We conducted population structure, phylogenomic and demographic analyses to reconstruct the evolutionary history of the species across Arabia. We also applied genotype-environment association methods to study adaptive mechanisms of lineage diversification. Our analyses revealed marked genetic structure and highly supported clades among and within the seas surrounding the Arabian Peninsula. Inferred divergence times were consistent with recent periods of low marine connectivity during glacial periods, revealing the presence of (cryptic) glacial refugia in the Red Sea and the Persian/Arabian Gulf. Genetic-environment association analyses revealed high levels of adaptive differentiation, and detected signs of multi-loci local adaptation driven by temperature extremes and hypersalinity. These results support a process of rapid diversification resulting from the combined effects of historical factors and ecological selection, and reveal mangrove peripheral environments as relevant drivers of lineage diversity.
  • Guava Leaf Essential Oil as a Potent Antioxidant and Anticancer Agent: Validated through Experimental and Computational Study

    Mandal, Ashok Kumar; Paudel, Samrat; Pandey, Anisha; Yadav, Parasmani; Pathak, Prateek; Grishina, Maria; Jaremko, Mariusz; Emwas, Abdul-Hamid M.; Khalilullah, Habibullah; Verma, Amita (Antioxidants, MDPI AG, 2022-11-07) [Article]
    Several drugs now employed in cancer therapy were discovered as a result of anticancer drug research based on natural products. Here, we reported the in vitro antioxidant and anticancer activity followed by in silico anticancer and estrogen-like activity of Psidium guajava L. essential oil against ER-α receptors which lead to potential inhibitory action against breast cancer pathways. Methods: The bioactive compounds in guava essential oil were screened using gas chromatography–mass spectrometry (GC-MS). Similarly, the antioxidant properties of the extracted oil were evaluated using 2,2-Diphenyl-1-picrylhydrazyl scavenging assay. Furthermore, the in vitro anticancer activity of guava oil was observed through the MTT assay and an in silico molecular docking experiment was also carried out to ensure that they fit into the estrogen receptors (ERs) and possess anticancer potential. Results: The GC–MS profile of the essential oil revealed the presence of 17 chemicals, with limonene (51.3%), eucalyptol (21.3%), caryophyllene oxide (6.2%), caryophyllene (5.6%), and nerolidol (4.5%) occupying more than one-third of the chromatographic spectrum zone. Guava leaves’ essential oil (EO) inhibited DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and exhibited concentration dependent free radical scavenging activity, acting as a potent antioxidant with an IC50 value of 29.3 ± 0.67 µg/mL. The outcome of the MTT assay showed that the extracted guava oil had nearly the same efficacy against breast and liver cancer cells at a low concentration (1 µg/mL), giving 98.3 ± 0.3% and 98.5 ± 0.4% cell viability against HepG2 at 1 µg/mL, respectively. When the concentration of essential oil was increased, it showed a small reduction in the percentage of viable cells. While conducting an in silico study of all the screened compounds, the potential for hydroxycaryophyllene, caryophyllene, caryophyllene oxide, humulene, terpineol, and calamenene to inhibit tumor growth was bolstered due to a resemblance to 4-hydroxytamoxifen, thereby implying that these compounds may act as selective estrogen receptor modulators (SERMs). The ADME analysis of the compounds indicated above revealed that they exhibit excellent drug likeness properties and follow the Lipinski rule of five. Conclusions: Consequently, they have a substantial anticancer therapeutic potential and can be used for novel drug discovery in the effort to minimize the global burden of breast cancer.
  • Phytoextracts as Crop Biostimulants and Natural Protective Agents—A Critical Review

    Akram, Nudrat Aisha; Saleem, Muhammad Hamzah; Shafiq, Sidra; Naz, Hira; Farid-ul-Haq, Muhammad; Ali, Baber; Shafiq, Fahad; Iqbal, Muhammad; Jaremko, Mariusz; Qureshi, Kamal A. (Sustainability, MDPI AG, 2022-11-04) [Article]
    Excessive application of synthetic chemicals to crops is a serious environmental concern. This review suggests that some potential natural compounds can be used as alternatives and could be applied directly to plants to improve crop growth and productivity. These phytoextracts can serve as biostimulants to induce abiotic and biotic stress tolerance in different crops growing under diverse environmental conditions. The biosynthesis and accumulation of a variety of chemical compounds such as glycinebetaine, vitamins, nutrients, and secondary metabolites in some plants are of great value and an environmentally friendly cheaper source than several synthetic substances of a similar nature. The review summarizes the information regarding the potential role of different plant phytoextracts and suggests subsequent applications to modulate crop stress tolerance. Future studies should focus on the relative effectiveness of these plant-based extracts compared with their synthetic counterparts and focus on practical applications to signify sustainable practices linked with the use of natural products.
  • Mountain- and brown hare genetic polymorphisms to survey local adaptations and conservation status of the heath hare (Lepus timidus sylvaticus, Nilsson 1831).

    Michell, Craig T; Pohjoismäki, Jaakko L. O.; Spong, Göran; Thulin, Carl-Gustaf (Scientific data, Springer Science and Business Media LLC, 2022-11-03) [Article]
    We provide the first whole genome sequences from three specimens of the mountain hare subspecies the heath hare (Lepus timidus sylvaticus), along with samples from two mountain hares (Lepus timidus timidus) and two brown hares (Lepus europaeus) from Sweden. The heath hare has a unique grey winter pelage as compared to other mountain hares (white) and brown hares (mostly brown), and face regional extinction, likely due to competitive exclusion from the non-native brown hare. Whole genome resequencing from the seven hare specimens were mapped to the Lepus timidus pseudoreference genome and used for detection of 11,363,883 polymorphic nucleotide positions. The data presented here could be useful for addressing local adaptations and conservation status of mountain hares and brown hares in Sweden, including unique subspecies.
  • Environmental micro-niche filtering shapes bacterial pioneer communities during primary colonization of a Himalayas' glacier forefield.

    Rolli, Eleonora; Marasco, Ramona; Fusi, Marco; Scaglia, Barbara; Schubotz, Florence; Mapelli, Francesca; Ciccazzo, Sonia; Brusetti, Lorenzo; Trombino, Luca; Tambone, Fulvia; Adani, Fabrizio; Borin, Sara; Daffonchio, Daniele (Environmental microbiology, Wiley, 2022-11-03) [Article]
    The pedogenesis from the mineral substrate released upon glacier melting has been explained with the succession of consortia of pioneer microorganisms, whose structure and functionality are determined by the environmental conditions developing in the moraine. However, the microbiome variability that can be expected in the environmentally heterogeneous niches occurring in a moraine at a given successional stage is poorly investigated. In a 50 m2 area in the forefield of the Lobuche glacier (Himalayas, 5,050 m a.s.l.), we studied six sites of primary colonization presenting different topographical features (orientation, elevation and slope) and harbouring greyish/dark biological soil crusts (BSCs). The spatial vicinity of the sites opposed to their topographical differences, allowed us to examine the effect of environmental conditions independently from the time of deglaciation. The bacterial microbiome diversity and their co-occurrence network, the bacterial metabolisms predicted from 16S rRNA gene high-throughput sequencing, and the microbiome intact polar lipids were investigated in the BSCs and the underlying sediment deep layers (DLs). Different bacterial microbiomes inhabited the BSCs and the DLs, and their composition varied among sites, indicating a niche-specific role of the micro-environmental conditions in the bacterial communities’ assembly. In the heterogeneous sediments of glacier moraines, physico-chemical and micro-climatic variations at the site-spatial scale are crucial in shaping the microbiome microvariability and structuring the pioneer bacterial communities during pedogenesis.
  • Importance of coastal vegetated habitats for tropical marine fishes in the Red Sea

    Dunne, Aislinn; Coker, Darren James; Kattan, Alexander; Tietbohl, Matthew D; Ellis, Joanne I; Jones, Burton; Berumen, Michael L. (Research Square Platform LLC, 2022-11-02) [Preprint]
    Marine vegetated habitats such as seagrass, mangroves, and macroalgae are common in tropical coastlines globally, providing habitats for a diversity of organisms. Many tropical fish use these habitats, including juvenile fish and species found on coral reefs. Understanding the use of these habitats by different fish species and life stages is fundamental to spatial planning, fisheries management, and conservation. While previous studies have focused on the habitat potential of seagrass, macroalgae, or mangroves for coral reef fish independently, it is important to consider their combined roles, as tropical seascapes are often mosaics of such habitats. In this study, we evaluated habitat associations across life stages for fish species in coral reefs, seagrasses, macroalgae, and mangroves in Saudi Arabia’s central Red Sea. Through in situ visual surveys, we documented 36% of local coral reef fish species in one or more vegetated habitats, with the fraction of coral reef species utilizing macroalgae or seagrass much greater than that of mangroves (29%, 18%, and 6%, respectively). Mangroves hosted mainly juvenile fish (83% of observed population) and macroalgae hosted the largest proportion of herbivores (39% of observed population), suggesting that each environment offers different combinations of resources (food and shelter), and a mix of these habitats could support biological connectivity across a seascape. Species targeted by local fisheries made up 37% of the species documented in vegetated habitats. The use of multiple habitat types by juvenile and commercially important fishes in the Red Sea underscores the need for a holistic approach to habitat protection.
  • Molecular phenotyping uncovers differences in basic housekeeping functions among closely related species of hares (Lepus spp., Lagomorpha: Leporidae)

    Gaertner, Kateryna; Michell, Craig; Tapanainen, Riikka; Goffart, Steffi; Saari, Sina; Soininmäki, Manu; Dufour, Eric; Pohjoismäki, Jaakko L. O. (Molecular Ecology, Wiley, 2022-11-01) [Article]
    Speciation is a fundamental evolutionary process, which results in genetic differentiation of populations and manifests as discrete morphological, physiological and behavioral differences. Each species has travelled its own evolutionary trajectory, influenced by random drift and driven by various types of natural selection, making the association of genetic differences between the species with the phenotypic differences extremely complex to dissect. In the present study, we have used an in vitro model to analyze in depth the genetic and gene regulation differences between fibroblasts of two closely related mammals, the arctic/subarctic mountain hare (Lepus timidus Linnaeus) and the temperate steppe-climate adapted brown hare (Lepus europaeus Pallas). We discovered the existence of a species-specific expression pattern of 1,623 genes, manifesting in differences in cell growth, cell cycle control, respiration, and metabolism. Interspecific differences in the housekeeping functions of fibroblast cells suggest that speciation acts on fundamental cellular processes, even in these two interfertile species. Our results help to understand the molecular constituents of a species difference on a cellular level, which could contribute to the maintenance of the species boundary.
  • First records of two large pelagic fishes in the Red Sea: wahoo (Acanthocybium solandri) and striped marlin (Kajikia audax)

    Williams, Collin T.; Arostegui, Martin C.; Braun, Camrin D.; Gaube, Peter; Shriem, Marwan; Berumen, Michael L. (Journal of the Marine Biological Association of the United Kingdom, Cambridge University Press (CUP), 2022-11-01) [Article]
    This report provides the first confirmed identifications of wahoo (Acanthocybium solandri) and striped marlin (Kajikia audax) in the Red Sea, expanding the known ranges of these species into the basin. Potential mechanisms responsible for the lack of regional documentation of the two species are further discussed. These findings illustrate the need for systematic biodiversity surveys of pelagic fish assemblages in the Red Sea.
  • Tiger sharks support the characterization of the world's largest seagrass ecosystem.

    Gallagher, Austin J; Brownscombe, Jacob W; Alsudairy, Nourah A; Casagrande, Andrew B; Fu, Chuancheng; Harding, Lucy; Harris, S David; Hammerschlag, Neil; Howe, Wells; Delgado-Huertas, Antonio; Kattan, Sami; Kough, Andrew S; Musgrove, Andre; Payne, Nicholas L; Phillips, Adrian; Shea, Brendan D; Shipley, Oliver N; Sumaila, U Rashid; Hossain, Mohammad S; Duarte, Carlos M. (Nature communications, Springer Science and Business Media LLC, 2022-11-01) [Article]
    Seagrass conservation is critical for mitigating climate change due to the large stocks of carbon they sequester in the seafloor. However, effective conservation and its potential to provide nature-based solutions to climate change is hindered by major uncertainties regarding seagrass extent and distribution. Here, we describe the characterization of the world’s largest seagrass ecosystem, located in The Bahamas. We integrate existing spatial estimates with an updated empirical remote sensing product and perform extensive ground-truthing of seafloor with 2,542 diver surveys across remote sensing tiles. We also leverage seafloor assessments and movement data obtained from instrument-equipped tiger sharks, which have strong fidelity to seagrass ecosystems, to augment and further validate predictions. We report a consensus area of at least 66,000 km2 and up to 92,000 km2 of seagrass habitat across The Bahamas Banks. Sediment core analysis of stored organic carbon further confirmed the global relevance of the blue carbon stock in this ecosystem. Data from tiger sharks proved important in supporting mapping and ground-truthing remote sensing estimates. This work provides evidence of major knowledge gaps in the ocean ecosystem, the benefits in partnering with marine animals to address these gaps, and underscores support for rapid protection of oceanic carbon sinks.
  • Biological Efficacy of Novel Metal Complexes of Nitazoxanide: Synthesis, Characterization, Anti-COVID-19, Antioxidant, Antibacterial and Anticancer Activity Studies

    Sharfalddin, Abeer A.; Inas Muta'eb Alyounis, Enas; Emwas, Abdul-Hamid M.; Jaremko, Mariusz (Journal of Molecular Liquids, Elsevier BV, 2022-11) [Article]
    It has been repeatedly reported that nitazoxanide (NTZ) exhibits a wide range of antiviral activities against various viral infections and has shown antimicrobial properties against anaerobic bacteria, helminths and protozoa. To improve these properties, three novel metal complexes were synthesized. The bidentate characteristic of the NTZ ligand was characterized by different spectroscopic techniques, including Fourier transform infrared (FT-IR), thermogravimetric, nuclear magnetic resonance (NMR) and UV−visible spectroscopy. The geometries of the formed compounds were evaluated by density functional theory, and the results revealed that NTZ-Ru(III) has an octahedral geometry, while NTZ-Au(III) and NTZ-Ag(I) complexes have distorted square planar structures. Binding between the metal complexes and calf thymus DNA (Ct-DNA) has been studied via absorption spectra. Moreover, human albumen serum (HAS) titration has been carried out to test their susceptibility to interact with a major target molecule via absorption and fluorescence spectroscopic techniques. Several in vitro bioassays were performed to evaluate the biological activity, antibacterial potency against E. coli, antioxidant activity and cytotoxicity of the ligand and the obtained complexes. The results showed that complexes Ru(III) and Au(III) have the highest radical scavenging percentage while the Ag(I) demonstrated the greatest antibacterial activity. Moreover, the metal complexes presented potentially effective against E. coli. Furthermore, compared with NTZ-Ag and the free ligand, the in vitro cytotoxicity assay showed that both NTZ-Ru(III) and NTZ-Au(III) exhibited significant anticancer activity against HeLa cells. The efficiency of the novel compounds as antivirals was tested by molecular docking with two COVID-19 receptors to obtain all interaction details.
  • Tritium and radiocarbon in the water column of the Red Sea

    Povinec, P. P.; Papadopoulos, V. P.; Krokos, Georgios; Abualnaja, Yasser; Pavlidou, A.; Kontuľ, I.; Kaizer, J.; Cherkinsky, A.; Molnár, A.; Molnár, M.; Palcsu, L.; Al Ghamdi, A. S.; Anber, H. A.; Al Othman, A. S.; Hoteit, Ibrahim (Journal of Environmental Radioactivity, Elsevier BV, 2022-10-27) [Article]
    Despite being the busiest transient sea in the world due to the Suez Canal, radionuclide distribution studies in seawater and sediment of the Red Sea remain rare. A sampling expedition in the Red Sea was conducted from June 9 to July 6, 2021, visiting a transect of several deep sampling stations located along the central axis of the basin from the Gulf of Aqaba to the southern Red Sea (near Farasan Island, Saudi Arabia). The collected seawater profile samples were analyzed for tritium, radiocarbon and oxygen-18. The observed tritium levels in surface waters of the Red Sea peaked at 0.3–0.4 TU, similar to the values observed in the western Arabian Sea (decay corrected). The values observed at waters below 150 m were around 0.2 TU, however, at depths of 450 and 750 m, tritium minima (<0.2 TU) were observed, which could be associated with a partial return flow of bottom waters from the southern to the northern Red Sea. At two stations at the depth of about 550 m, deep Δ14C minima were observed as well (−4‰ and −10‰), documenting ongoing transport of carbon in the water column, important for sink of anthropogenic carbon.
  • Preparation and characterization of natural melanin and its nanocomposite formed by copper doping

    Khouqeer, Ghada; Alghrably, Mawadda; Madkhali, Nawal; Dhahri, Manel; Jaremko, Mariusz; Emwas, Abdul-Hamid (Nano Select, Wiley, 2022-10-27) [Article]
    Natural Melanins have received great interest due to their structural, thermostability, electrochemical and paramagnetic properties. Pure melanin (Mel) is extracted from Nigella Sativa seeds and doped with Copper (Cu-Mel) to form nano-composite melanin using wet chemical methods. Several analytics techniques are utilized to evaluate the effects of cop-per doping on the characteristics of melanin. Thermogravimetric analysis (TGA) is employed to measure the thermal stability of Cu-Mel relative to Mel. The morphological characterization is explored using Transmission Electron Microscopy (TEM) while X-Ray Diffraction (XRD) is used to probe the samples’ structure. Vibrating Sample Magnetometer (VSM) is employed to study the magnetic properties of the prepared samples at 10 and 300K. Chemical properties are determined by Spectroscopic techniques such as UV–Vis spectroscopy, RAMAN spectroscopy, Fourier-Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR) spectroscopy, and Electron Paramagnetic Resonance (EPR) spectroscopy. The results show that Mel and Cu-Mel are non-crystalline with different structural, optical, and magnetic properties. The EPR analysis provided evidence of copper coordination with herbal Mel and the copper doping improved the magnetic properties of Mel from diamagnetic to paramagnetic at low temperature (10K). Overall, this investigation shows that Mel and Cu-Mel are non-crystalline with different structural and magnetic properties.
  • High-resolution climate characteristics of the Arabian Gulf based on a validated regional reanalysis

    Dasari, Hari Prasad; Vijaya Kumari, K.; Langodan, Sabique; Abualnaja, Yasser; Desamsetti, Srinivas; Vankayalapati, Koteswararao; Thang, Luong; Hoteit, Ibrahim (Meteorological Applications, Wiley, 2022-10-26) [Article]
    The regional climate of the Arabian Gulf (AG) and its variability are examined based on a 40-year (1980–2019), 5-km regional reanalysis of the Arabian Peninsula (AP reanalysis). The AP reanalysis fields were first validated against the available observations over the AG, suggesting that this high-resolution reanalysis well reproduces the spatio-temporal features of the AG atmospheric circulations. The validated AP reanalysis fields were then analysed to examine the climatic characteristics over the AG including the monthly mean, maximum and minimum temperatures, and the seasonal variations in winds, relative humidity and rainfall over the AG. The AG climate is mostly dry between May and October, and experiences moderate rainfall between December and January. The higher (lower) pressure difference between the northwest and southeast AG during summer (winter) generates the northwesterly Shamal winds over the north (central) AG. The mean Shamal winds are relatively stronger (weaker) and prolonged (shorter) during summer (winter); however, the short lived Shamal jet events in winter can be occasionally stronger than summer. In terms of interannual variability, the Shamal winds are stronger and more persistent in summer during El Niño years and in winter during La Niña years. These differences are mainly associated with changes in temperature gradients between the eastern AG and northwestern AP.
  • Pathways for Understanding Blue Carbon Microbiomes with Amplicon Sequencing.

    Hurtado-McCormick, Valentina; Trevathan-Tackett, Stacey M.; Bowen, Jennifer L; Connolly, Rod M; Duarte, Carlos M.; Macreadie, Peter I (Microorganisms, MDPI AG, 2022-10-26) [Article]
    The capacity of Blue Carbon Ecosystems to act as carbon sinks is strongly influenced by the metabolism of soil-associated microbes, which ultimately determine how much carbon is accumulated or returned to the atmosphere. The rapid evolution of sequencing technologies has facilitated the generation of tremendous amounts of data on what taxa comprise belowground microbial assemblages, largely available as isolated datasets, offering an opportunity for synthesis research that informs progress on understanding Blue Carbon microbiomes. We identified questions that can be addressed with a synthesis approach, including the high variability across datasets, space, and time due to differing sampling techniques, ecosystem or vegetation specificity, and the relationship between microbiome community and edaphic properties, particularly soil carbon. To address these questions, we collated 34 16S rRNA amplicon sequencing datasets, including bulk soil or rhizosphere from seagrass, mangroves, and saltmarshes within publicly available repositories. We identified technical and theoretical challenges that precluded a synthesis of multiple studies with currently available data, and opportunities for addressing the knowledge gaps within Blue Carbon microbial ecology going forward. Here, we provide a standardisation toolbox that supports enacting tasks for the acquisition, management, and integration of Blue Carbon-associated sequencing data and metadata to potentially elucidate novel mechanisms behind Blue Carbon dynamics.
  • Coral bleaching due to cold stress on a central Red Sea reef flat

    Rich, Walter A.; Carvalho, Susana; Berumen, Michael L. (Ecology and Evolution, Wiley, 2022-10-22) [Article]
    Ocean warming is leading to more frequent coral bleaching events. However, cold stress can also induce bleaching in corals. Here, we report observations of a boreal winter bleaching event in January 2020 in the central Red Sea, mainly within a population of the branching coral Stylophora pistillata on an offshore reef flat. Sea surface temperatures (SSTs) rarely fall below 24°C in this region, but data loggers deployed on several nearby reef flats recorded overnight seawater temperatures as low as 18°C just 3 days before the observations. The low temperatures coincided with an extremely low tide and cool air temperatures, likely resulting in the aerial exposure of the corals during the night time low-tide event. The risk of aerial exposure is rare in winter months, as the Red Sea exhibits seasonal fluctuations in sea level with winter values typically 0.3–0.4 m higher than in summer. These observations are notable for a region typically characterized as a high-temperature sea, and highlight the need for long-term monitoring programs as this rare event may have gone unnoticed.
  • Consequences of supplementing duck's diet with charcoal on carcass criteria, meat quality, nutritional composition, and bacterial load

    Farghly, Mohamed F.A.; Elsagheer, Mohamed A.; Jghef, Muthana M.; Taha, Ayman E.; El-Hack, Mohamed E. Abd; Jaremko, Mariusz; El-Tarabily, Khaled A.; Shabaan, Mahmoud (Poultry Science, Elsevier BV, 2022-10-22) [Article]
    The influence of charcoal as feed additives on carcass and meat characteristics was studied in 144 four weeks old Muller ducks. The experimental ducklings were assigned to six groups of 24 birds (eight per replicates each). The dietary treatments contained 0, 0.5, 1.0, 1.5, 2.0 and 2.5% charcoal for G1 (C), G2 (L1), G3 (L2), G4 (L3), G5 (L4) and G6 (L5), respectively. All experimental birds were raised under similar environmental and managerial conditions. Results indicated that charcoal did not affect most carcass traits significantly except for dressing percentage (DP %) was higher (P<0.05) in 1.5 and 2 % charcoal included ducks diets compared to control ducks. Charcoal supplementation significantly affected duck meat tenderness, juiciness and water holding capacity (WHC). Moreover, charcoal altered (P<0.05) meat components such as crud protein, calcium components, desirable fatty acids, nutritional value and some microbial counts. Thiobarbituric acid reactive substances (TBARS) reduced in birds fed charcoal at 1.5, 2 and 2.5%, with significance varying among treatments. No significant differences in the number of Escherichia coli and Staphylococcus aureus were noticed among the ducks fed with charcoal and the control group. It could be concluded that charcoal could be included in ducks’ diets at 1.5 and 2 % with beneficial effects on carcass parameters.

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