Synergistic impact of natural gums and crosslinkers on the properties of oilseed meals based biopolymeric films.

The waste material utilization from available agricultural resources can be beneficial in the field of economic, social, and environmental well-being. One of the main industrial crops used to manufacture oil from oilseeds worldwide is agricultural waste, such as the cake made from oilseeds. In this study, de-oiled cakes are used to create biopolymeric films. Three widely accessible oilseed meals viz. flaxseed, soybean, and mustard were gathered, ground, and sieved. A film forming suspension of defatted meals along with natural gums (acacia and xanthan gum) and crosslinkers (citric acid and glutaraldehyde) were formed. The suspension was cast into petri dishes and dried to produce smooth and even films. The physical, functional, color, thermal and morphological properties of the oilseed meals-gums crosslinked biopolymeric film were evaluated and statistical analysis was performed. The solubility was found to be decreased and tensile strength was increased with the addition of citric acid and increase in tensile strength. There was significant difference observed in the values of elongation at break after addition of citric acid as crosslinker. The research shows how oilseed meals enriched with natural gum and crosslinkers may be converted into biopolymeric films, which can then be used in food packaging to lessen reliance on petroleum-based, non-biodegradable plastics.

Comparative Analysis of Inhibitor Binding to Peroxiredoxins from Candidatus Liberibacter asiaticus and Its Host Citrus sinensis.

The peroxiredoxins (Prxs), potential drug targets, constitute an important class of antioxidant enzymes present in both pathogen and their host. The comparative binding potential of inhibitors to Prxs from pathogen and host could be an important step in drug development against pathogens. Huanglongbing (HLB) is a most devastating disease of citrus caused by Candidatus Liberibacter asiaticus (CLa). In this study, the binding of conoidin-A (conoidin) and celastrol inhibitor molecules to peroxiredoxin of bacterioferritin comigratory protein family from CLa (CLaBCP) and its host plant peroxiredoxin from Citrus sinensis (CsPrx) was assessed. The CLaBCP has a lower specific activity than CsPrx and is efficiently inhibited by conoidin and celastrol molecules. The biophysical studies showed conformational changes and significant thermal stability of CLaBCP in the presence of inhibitor molecules as compared to CsPrx. The surface plasmon resonance (SPR) studies revealed that the conoidin and celastrol inhibitor molecules have a strong binding affinity (KD) with CLaBCP at 33.0 µM, and 18.5 µM as compared to CsPrx at 52.0 µM and 61.6 µM, respectively. The docked complexes of inhibitor molecules showed more structural stability of CLaBCP as compared to CsPrx during the run of molecular dynamics-based simulations for 100 ns. The present study suggests that the conoidin and celastrol molecules can be exploited as potential inhibitor molecules against the CLa to manage the HLB disease.

Cellular uptake of metal oxide-based nanocomposites and targeting of chikungunya virus replication protein nsP3.

Emergence of new pathogenic viruses along with adaptive potential of RNA viruses has become a major public health concern. Therefore, it is increasingly crucial to investigate and assess the antiviral potential of nanocomposites, which is constantly advancing area of medical biology. In this study, two types of nanocomposites: Ag/NiO and Ag2O/NiO/ZnO with varying molar ratios of silver and silver oxide, respectively have been synthesised and characterised. Three metal/metal oxide (Ag/NiO) composites having different amounts of Ag nanoparticles (NPs) anchored on NiO octahedrons are AN-5 % (5 % Ag), AN-10 % (10 % Ag) and AN-15 % (15 % Ag)) and three ternary metal oxide nanocomposites (Ag2O/NiO/ZnO) i.e., A/N/Z-1, A/N/Z-2, and A/N/Z-3 with different molar ratios of silver oxide (10 %, 20 % and 30 %, respectively) were evaluated for their antiviral potential. Cellular uptake of nanocomposites was confirmed by ICP-MS. Intriguingly, molecular docking of metal oxides in the active site of nsP3 validated the binding of nanocomposites to chikungunya virus replication protein nsP3. In vitro antiviral potential of nanocomposites was tested by performing plaque reduction assay, cytopathic effect (CPE) analysis and qRT-PCR. The nanocomposites showed significant reduction in virus titre. Half-maximal inhibitory concentration (IC50) for A/N/Z-3 and AN-5 % were determined to be 2.828 and 3.277 µg/mL, respectively. CPE observation and qRT-PCR results were consistent with the data obtained from plaque reduction assay for A/N/Z-3 and AN-5 %. These results have opened new avenues for development of nanocomposites based antiviral therapies.

Multi-target direct-acting SARS-CoV-2 antivirals against the nucleotide-binding pockets of virus-specific proteins.

The nucleotide-binding pockets (NBPs) in virus-specific proteins have proven to be the most successful antiviral targets for several viral diseases. Functionally important NBPs are found in various structural and non-structural proteins of SARS-CoV-2. In this study, the first successful multi-targeting attempt to identify effective antivirals has been made against NBPs in nsp12, nsp13, nsp14, nsp15, nsp16, and nucleocapsid (N) proteins of SARS-CoV-2. A structure-based drug repurposing in silico screening approach with ADME analysis identified small molecules targeting NBPs in SARS-CoV-2 proteins. Further, isothermal titration calorimetry (ITC) experiments validated the binding of top hit molecules to the purified N-protein. Importantly, cell-based antiviral assays revealed antiviral potency for INCB28060, darglitazone, and columbianadin with EC50 values 15.71 µM, 5.36 µM, and 22.52 µM, respectively. These effective antivirals targeting multiple proteins are envisioned to direct the development of antiviral therapy against SARS-CoV-2 and its emerging variants.

Characterization of a cytoplasmic 2-Cys peroxiredoxin from Citrus sinensis and its potential role in protection from oxidative damage and wound healing.

In present work, the recombinant cytoplasmic 2-Cys peroxiredoxin from Citrus sinensis (CsPrx) was purified and characterized. The peroxidase activity was examined with different substrates using DTT, a non-physiological electron donor. The conformational studies, in oxidized and reduced states, were performed using circular dichroism (CD) and fluorescence measurement. The CD analysis showed higher α-helical content for reduced state of the protein. The thermal stability studies of CsPrx by Differential Scanning Calorimetry (DSC) showed that oxidized state is more stable as compared to the reduced state of CsPrx. In vitro studies showed that the CsPrx provides a protective shield against ROS and free radicals that participate in the degradation of plasmid DNA. The pre-treatment of 10 µM CsPrx provide almost 100% protection against peroxide-mediated cell killing in the Vero cells. CsPrx showed significant cell proliferation and wound healing properties. The superior morphology of viable cells and wound closure was found at 20 µM CsPrx treated for 12 h. The results demonstrated that CsPrx is a multifaceted protein with a significant role in cell proliferation, wound healing and protection against hydrogen peroxide-induced cellular damage. This could be the first report of a plant peroxiredoxin being characterized for biomedical applications.

Spatial control of cell division by GA-OsGRF7/8 module in a leaf explaining the leaf length variation between cultivated and wild rice.

Cellular and genetic understanding of the rice leaf size regulation is limited, despite rice being the staple food of more than half of the global population. We investigated the mechanism controlling the rice leaf length using cultivated and wild rice accessions that remarkably differed for leaf size. Comparative transcriptomics, gibberellic acid (GA) quantification and leaf kinematics of the contrasting accessions suggested the involvement of GA, cell cycle and growth-regulating factors (GRFs) in the rice leaf size regulation. Zone-specific expression analysis and VIGS established the functions of specific GRFs in the process. The leaf length of the selected accessions was strongly correlated with GA levels. Higher GA content in wild rice accessions with longer leaves and GA-induced increase in the leaf length via an increase in cell division confirmed a GA-mediated regulation of division zone in rice. Downstream to GA, OsGRF7 and OsGRF8 function for controlling cell division to determine the rice leaf length. Spatial control of cell division to determine the division zone size mediated by GA and downstream OsGRF7 and OsGRF8 explains the leaf length differences between the cultivated and wild rice. This mechanism to control the rice leaf length might have contributed to optimizing leaf size during domestication.

Evaluation of the Antiviral Potential of Halogenated Dihydrorugosaflavonoids and Molecular Modeling with nsP3 Protein of Chikungunya Virus (CHIKV).

Antiviral therapy is crucial for the circumvention of viral epidemics. The unavailability of a specific antiviral drug against the chikungunya virus (CHIKV) disease has created an alarming situation to identify or develop potent chemical molecules for remedial management of CHIKV. In the present investigation, in silico studies of dihydrorugosaflavonoid derivatives (5a-f) with non-structural protein-3 (nsP3) were carried out. nsP3 replication protein has recently been considered as a possible antiviral target in which crucial inhibitors fit into the adenosine-binding pocket of the macrodomain. The 4'-halogenated dihydrorugosaflavonoids displayed intrinsic binding with the nsp3 macrodomain (PDB ID: 3GPO) of CHIKV. Compounds 5c and 5d showed docking scores of -7.54 and -6.86 kcal mol-1, respectively. Various in vitro assays were performed to confirm their (5a-f) antiviral potential against CHIKV. The non-cytotoxic dose was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and was found to be <100 µM. The compounds 5c and 5d showed their inhibitory potential for CHIKV, which was determined through cytopathic effect assay and plaque reduction assay, which show inhibition up to 95 and 92% for 70 µM concentration of the compounds, respectively. The quantitative real-time polymerase chain reaction assay result confirmed the ability of 5c and 5d to reduce the viral RNA level at 70 µM concentration of compounds to nearly 95 and 93% concentration, respectively, in cells with CHIKV infection. Further, the CHIKV-inhibitory capacity of these compounds was corroborated by execution of immunofluorescence assay. The executed work will be meaningful for the future research of studied dihydrorugosaflavonoids against prime antiviral entrants, leading to remedial management to preclude CHIKV infection.