Suitability of inorganic coagulants for algae-laden water treatment: Trade-off between algae removal and cell viability, aggregate properties and coagulant residue

Inorganic coagulants could effectively precipitate algae cells but might increase the potential risks of cell damage and coagulant residue. This study was conducted to critically investigate the suitability of polyaluminum (PAC), FeCl3 and TiCl4 for algae-laden water treatment in terms of the trade-off between algal substance removal, cell viability, and coagulant residue. The results showed that an appropriate increase in coagulant dosage contributed to better coagulation performance but severe cell damage and a higher risk of intracellular organic matter (IOM) release. TiCl4 was the most destructive, resulting in 60.85% of the algal cells presenting membrane damage after coagulation. Intense hydrolysis reaction of Ti salts was favorable for the formation of larger and more elongated, dendritic structured flocs than Al and Fe coagulants. TiCl4 exhibited the lowest residue level and remained in the effluents mainly in colloidal form. The study also identified charge neutralization, chemisorption, enmeshment, and complexation as the dominant mechanisms for algae water coagulation by metal coagulants. Overall, this study provides the trade-off analyses between maximizing algae substance removal and minimizing potential damage to cell integrity and is practically valuable to develop the most suitable and feasible technique for algae-laden water treatment.

Toward nitrogen recovery: Co-cultivation of microalgae and bacteria enhances the production of high-value nitrogen-rich cyanophycin

The algal-bacterial wastewater treatment process has been proven to be highly efficient in removing nutrients and recovering nitrogen (N). However, the recovery of the valuable N-rich biopolymer, cyanophycin, remains limited. This research explored the synthesis mechanism and recovery potential of cyanophycin within two algal-bacterial symbiotic reactors. The findings reveal that the synergy between algae and bacteria enhances the removal of N and phosphorus. The crude contents of cyanophycin in the algal-bacterial consortia reached 115 and 124 mg/g of mixed liquor suspended solids (MLSS), respectively, showing an increase of 11.7 %-20.4 % (p < 0.001) compared with conventional activated sludge. Among the 170 metagenome-assembled genomes (MAGs) analyzed, 50 were capable of synthesizing cyanophycin, indicating that cyanophycin producers are common in algal-bacterial systems. The compositions of cyanophycin producers in the two algal-bacterial reactors were affected by different lighting initiation time. The study identified two intracellular synthesis pathways for cyanophycin. Approximately 36 MAGs can synthesize cyanophycin de novo using ammonium and glucose, while the remaining 14 MAGs require exogenous arginine for production. Notably, several MAGs with high abundance are capable of assimilating both nitrate and ammonium into cyanophycin, demonstrating a robust N utilization capability. This research also marks the first identification of potential horizontal gene transfer of the cyanophycin synthase encoding gene (cphA) within the wastewater microbial community. This suggests that the spread of cphA could expand the population of cyanophycin producers. The study offers new insights into recycling the high-value N-rich biopolymer cyanophycin, contributing to the advancement of wastewater resource utilization.

MOF-derived Fe/Ni@C marigold-like nanosheets as heterogeneous electro-Fenton cathode for efficient antibiotic oxytetracycline degradation

The widespread occurrence of organic antibiotic pollution in the environment and the associated harmful effects necessitate effective treatment method. Heterogeneous electro-Fenton (hetero-EF) has been regarded as one of the most promising techniques towards organic pollutant removal. However, the preparation of efficient cathode still remains challenging. Herein, a novel metal-organic framework (MOF)-derived Fe/Ni@C marigold-like nanosheets were fabricated successfully for the degradation of oxytetracycline (OTC) by serving as the hetero-EF cathode. The FeNi3@C (Fe/Ni molar ratio of 1:3) based hetero-EF system exhibited 8.2 times faster OTC removal rate than that of anodic oxidation and possessed many advantages such as excellent OTC degradation efficiency (95.4% within 90 min), broad environmental adaptability (satisfactory treatment performance for multiple antibiotics under various actual water matrixes), good stability and reusability, and significant toxicity reduction. The superior hetero-EF catalytic performance was mainly attributed to: 1) porous carbon and Ni existence were both conducive to the in-situ generation of H2O2 from dissolved O2; 2) the synergistic effects of bimetals together with electron transfer from the cathode promoted the regeneration of ≡ FeII/NiII, thereby accelerating the production of reactive oxygen species; 3) the unique nanosheet structure derived from the precursor two-dimensional Fe-Ni MOFs enhanced the accessibility of active sites. This work presented a promising hetero-EF cathode for the electrocatalytic treatment of antibiotic-containing wastewaters.

Refining microbial potentiometric sensor performance with unique cathodic catalytic properties for targeted application scenarios

Traditional microbial electrochemical sensors encounter challenges due to their inherent complexity. In response to these challenges, the microbial potentiometric sensor (MPS) technology was introduced, featuring a straightforward high-impedance measurement circuit tailored for environmental monitoring. Nonetheless, the practical implementation of conventional MPS is constrained by issues such as the exposure of the reference electrode to the monitored water and the absence of methodologies to stimulate microbial metabolism. In this study, our objective was to enhance MPS performance by imbuing it with unique cathodic catalytic properties, specifically tailored for distinct application scenarios. Notably, the anodic region served as the sensing element, with both the cathodic region and reference electrode physically isolated from the analyzed water sample. In the realm of organic monitoring, the sensor without Pt/C coated in the cathodic region exhibited a faster response time (1 h) and lower detection limits (1 mg L-1 BOD, 1 mM acetic acid). Conversely, when monitoring toxic substances, the sensor with Pt/C showcased a lower detection limit (0.004% formaldehyde), while the Pt/C-free sensor demonstrated superior reusability. The sensor with Pt/C displayed a heightened anode biofilm thickness and coverage, predominantly composed of Rhodococcus. In conclusion, this study introduces simple, cost-effective, and tailorable biosensors holding substantial promise for water quality monitoring.

The effect of quorum sensing on cadmium- and lead-containing wastewater treatment using activated sludge: Removal efficiency, enzyme activity, and microbial community

Quorum sensing (QS) is prevalent in activated sludge processes; however, its essential role in the treatment of heavy metal wastewater has rarely been studied. Therefore, in this study, acyl homoserine lactone (AHL)-mediated QS was used to regulate the removal performance, enzyme activity, and microbial community of Cd- and Pb-containing wastewater in a sequencing batch reactor (SBR) over 30 cycles. The results showed that exogenous AHL strengthened the removal of Cd(II) and Pb(II) in their coexistence wastewater during the entire period. The removal of NH4+-N, total phosphorus, and chemical oxygen demand (COD) was also enhanced by the addition of AHL despite the coexistence of Cd(II) and Pb(II). Meanwhile, the protein content of extracellular polymeric substances was elevated and the microbial metabolism and antioxidative response were stimulated by the addition of AHL, which was beneficial for resistance to heavy metal stress and promoted pollutant removal by activated sludge. Microbial sequencing indicated that AHL optimized the microbial community structure, with the abundance of dominant taxa Proteobacteria and Unclassified_f_Enterobacteriaceae increasing by 73.9% and 59.2% maximally, respectively. This study offers valuable insights into the mechanisms underlying Cd(II) and Pb(II) removal as well as microbial community succession under AHL availability in industrial wastewater.

l-Cysteine and barium titanate co-modified enteromorpha biochar as effective peroxymonosulfate activator for atrazine treatment

In this study, pyrolysis and hydrothermal methods were used for Enteromorpha biochar that was co-modified with l-cysteine and barium titanate (LBCBa). It has great environmental tolerance and can remove 93.0 % of atrazine (ATZ, 10 mg·L-1) within 60 mins of ultrasonic treatment. The enhanced hydrophilicity, electron-donating capability, and piezoelectricity of LBCBa are considered to induce excellent performance. The apparent reaction rate of the LBCBa-2/PMS/ATZ system with ultrasonic was 2.87 times that without ultrasonic. The density functional theory points out that, introducing l-cysteine to carbon edges improves the adsorption of ATZ and peroxymonosulfate (PMS), making PMS easier to activate. This work offered unique insights for fabricating effective catalysts and demonstrated the combination of hydrophilic functional groups and piezoelectricity in improving catalytic performance and stability.

Insights into the rapid start-up of an inoculated municipal sludge system: A high-height-to-diameter-ratio airlift inner-circulation partition bioreactor based on CFD analysis

The utilization of municipal sludge as a seed sludge for initiating the autotrophic nitrogen removal (ANR) process presents a challenge due to the negligible abundance of anaerobic ammonia-oxidizing bacteria (AnAOB). Here, a computational fluid dynamics model was used to simulate sludge volume fraction and sludge particle velocity. A high-height-to-diameter-ratio airlift inner-circulation partition bioreactor (HHAIPBR) was operated for 175 d to enrich AnAOB from municipal sludge, and the performance of the ANR process was investigated. The start-up period of HHAIPBR inoculated with municipal sludge required approximately 69 d. A high nitrogen removal performance, with a mean total nitrogen removal efficiency of 82.1%, was obtained for 1 month. The simulation results validated the presence of sludge circulation and revealed the distribution characteristics of dissolved oxygen inside the reactor, further supporting the promotion of sludge granulation via the high height-to-diameter ratio. Nitrosomonas (3.31%) of Proteobacteria and Candidatus Brocadia (6.56%) of Planctomycetota were dominant in the HHAIPBR. This study presents a viable approach for the industrial cultivation of anammox sludge and the rapid start-up of the partial nitritation-anammox system.

Effects of biochar layer position on treatment performance and microbial community in subsurface flow constructed wetlands for removal of cadmium and lead

Levels of cadmium (Cd) and lead (Pb) correspond to common composition in acid mine wastewater of Hunan Province of China. The removal path of Cd and Pb and the structure of microbial community were investigated by developing constructed wetlands (CWs) with different layer positions of biochar. The biochar as a layer at the bottom of CW (BCW) system exhibited maximum Cd and Pb removal efficiencies of 96.6-98.6% and 97.2-98.9%, respectively. Compared with original soil, BCW increased the relative proportions of Proteobacteria, Firmicutes, Acidobacteriota, Verrucomicrobiota, Desulfobacterota, Armatimonadota, Bacteroidota, Patescibacteria, Basidiomycota (phylum level) and Burkholderia-Caballeronia-Paraburkholderia, Citrifermentans, Chthonomonadales, Cellulomonas, Geothrix, Terracidiphilus, Gallionellaceae, Microbacterium, Vanrija, Apiotrichum, Saitozyma, Fusarium (genus level). The concentrations of Cd and Pb were positively correlated with the abundance of Verrucomicrobiota, Basidiomycota (phylum level), and Methylacidiphilaceae, Meyerozyma, Vanrija (genus level). This study demonstrates that BCW system can improve removal performance toward Cd and Pb, as well as alter microbial community.

Robust rehabilitation of anammox system by granular activated carbon under long-term starvation stress: Microbiota restoration and metabolic reinforcement

This article investigates the buffering capacity and recovery-enhancing ability of granular activated carbon (GAC) in a starved (influent total nitrogen: 20 mg/L) anaerobic ammonium oxidation (anammox) reactor. The findings revealed that anammox aggregated and sustained basal metabolism with shorter performance recovery lag (6 days) and better nitrogen removal efficiency (84.9 %) due to weak electron-repulsion and abundance redox-active groups on GAC's surface. GAC-supported enhanced extracellular polymeric substance secretion aided anammox in resisting starvation. GAC also facilitated anammox bacterial proliferation and expedited the restoration of anammox microbial community from a starved state to its initial-level. Metabolic function analyses unveiled that GAC improved the expression of genes involved in amino acid metabolism and sugar-nucleotide biosynthesis while promoted microbial cross-feeding, ultimately indicating the superior potential of GAC in stimulating more diverse metabolic networks in nutrient-depleted anammox consortia. This research sheds light on the microbial and metabolic mechanisms underlying GAC-mediated anammox system in low-substrate habitats.

Relative contribution of ammonia-oxidizing bacteria and denitrifying fungi to N2O production during rice straw composting with biochar and biogas residue amendments

Nitrous oxide (N2O) production is associated with ammonia-oxidizing bacteria (amoA-AOB) and denitrifying fungi (nirK-fungi) during the incorporation of biochar and biogas residue composting. This research examined the relative contribution of alterations in the abundance, diversity and structure of amoA-AOB and nirK-fungi communities on N2O emission by real-time PCR and sequence processing. Results showed that N2O emissions showed an extreme relation with the abundance of amoA-AOB (rs = 0.584) while giving credit to nirK-fungi (rs = 0.500). Nitrosomonas and Nitrosospira emerged as the dominant genera driving ammoxidation process. Biogas residue changed the community structure of AOB by altering Nitrosomonadaceae proportion and physiological capacity. The denitrification process, primarily governed by nirK-fungi, served as a crucial pathway for N2O production, unveiling the pivotal mechanism of biochar to suppress N2O emissions. C/N and NH4+-N were identified as significant parameters influencing the distribution of nirK-fungi, especially Micromonospora, Halomonas and Mesorhizobium.

Antibacterial activity of peptides and bio-safety evaluation: in vitro and in vivo studies against bacterial and fungal pathogens

BACKGROUND

Antimicrobial peptides are promising alternatives to antibiotics to treat bacterial and fungal infections, especially drug-resistant clinical pathogens.

METHODS

Antimicrobial peptides (AMPs) were synthesized and antimicrobial activity was assayed. The antibacterial mechanism, ATP production, ROS generation and molecular mechanism were determined. Biofilm inhibition assay was performed in planktonic bacterial cells and biofilm degradation assay was performed using mature biofilm. The synthesized AMP2 was subjected to in vitro and in vivo analysis to analyze the safety.

RESULTS

The synthesized peptides AMP1, AMP2, AMP3 and AMP4 exhibited antimicrobial activity against Gram-positive and Gram-negative bacteria. The MIC values ranged from 1.5 ± 0.25-12.5 ± 1.25 µM and the MFC values range from 2.25 ± 0.12-25 ± 1.25 µM. F. solani showed fewer MFC values than other fungal strains. Time kill assay was performed and the AMP2 killed about 70 % of Acinetobacter baumannii at 1 × MIC concentration within 10 min incubation and killed 97 % of bacteria at 1 × MBC concentration within 15 min. The antimicrobial peptide AMP2 was highly effective against planktonic A. baumannii and L. monocytogenes. The tested AMP2 showed less toxicity to cell lines and Zebrafish.

CONCLUSIONS

Antimicrobial peptides have potential antimicrobial properties against Gram-positive and Gram-negative bacteria. The in silico studies of these antimicrobial peptides are useful for eradicating drug-resistant bacteria.

Reduced metal nanocatalysts for selective electrochemical hydrogenation of biomass-derived 5-(hydroxymethyl)furfural to 2,5-bis(hydroxymethyl)furan in ambient conditions

Selective electrochemical hydrogenation (ECH) of biomass-derived unsaturated organic molecules has enormous potential for sustainable chemical production. However, an efficient catalyst is essential to perform an ECH reaction consisting of superior product selectivity and a higher conversion rate. Here, we examined the ECH performance of reduced metal nanostructures, i.e., reduced Ag (rAg) and reduced copper (rCu) prepared via electrochemical or thermal oxidation and electrochemical reduction process, respectively. Surface morphological analysis suggests the formation of nanocoral and entangled nanowire structure formation for rAg and rCu catalysts. rCu exhibits a slight enhancement in ECH reaction performance in comparison to the pristine Cu. However, the rAg exhibits more than two times higher ECH performance without compromising the selectivity for 5-(HydroxyMethyl) Furfural (HMF) to 2,5-bis(HydroxyMethyl)-Furan (BHMF) formation in comparison to the Ag film. Moreover, a similar ECH current density was recorded at a reduced working potential of 220 mV for rAg. This high performance of rAg is attributed to the formation of new catalytically active sites during the Ag oxidation and reduction processes. This study demonstrates that rAg can potentially be used for the ECH process with minimum energy consumption and a higher production rate.

PS9, Derived from an Aquatic Fungus Virulent Protein, Glycosyl Hydrolase, Arrests MCF-7 Proliferation by Regulating Intracellular Reactive Oxygen Species and Apoptotic Pathways

One of the most common diseases in women is breast cancer, which has the highest death globally. Surgery, chemotherapy, hormone treatments, and radiation are the current treatment options for breast cancer. However, these options have several adverse side effects. Recently, peptide-based drugs have gained attention as anticancer therapy. Studies report that peptides from biological toxins such as venom and virulent pathogenic molecules have potential therapeutic effects against multiple diseases, including cancers. This study reports on the in vitro anticancer effect of a short peptide, PS9, derived from a virulent protein, glycosyl hydrolase, of an aquatic fungus, Aphanomyces invadans. This peptide arrests MCF-7 proliferation by regulating intercellular reactive oxygen species (ROS) and apoptotic pathways. Based on the potential for the anticancer effect of PS9, from the in silico analysis, in vitro analyses using MCF-7 cells were executed. PS9 showed a dose-dependent activity; its IC50 value was 25.27-43.28 μM at 24 h. The acridine orange/ethidium bromide (AO/EtBr) staining, to establish the status of apoptosis in MCF-7 cells, showed morphologies for early and late apoptosis and necrotic cell death. The 2,7-dichlorodihydrofluorescein diacetate (DCFDA) staining and biochemical analyses showed a significant increase in reactive oxygen species (ROS). Besides, PS9 has been shown to regulate the caspase-mediated apoptotic pathway. PS9 is nontoxic, in vitro, and in vivo zebrafish larvae. Together, PS9 may have an anticancer effect in vitro.

Bacterial clearance and anti-inflammatory effect of Withaferin A against human pathogen of Staphylococcus aureus in infected zebrafish

The emergence of antibiotic resistance is the most challenging factor for developing a proper drug to treat S. aureus infection. These bacterial pathogens can survive in fresh water and spread to various environments. Plant sources, especially pure compounds, are the material of interest amongst researchers for developing drugs of therapeutic value. Here, we report the bacterial clearance and anti-inflammatory potential of the plant compound Withaferin A, using the zebrafish infection model. The minimum inhibitory concentration of the Withaferin A was calculated as 80 µM against S. aureus. The DAPI/PI staining and scanning electron microscopy analysis showed the pore-forming mechanism of Withaferin A on the bacterial membrane. Along with the antibacterial activity, the results from the tube adherence test reveal the antibiofilm property of Withaferin A. In vivo studies were demonstrated to determine the effect of Withaferin A on survival, inflammatory response and behavioural changes during S. aureus infection. Staining zebrafish larvae with neutral red and Sudan black indicates a substantial decrease in the number of localized macrophages and neutrophils. The gene expression analysis showed the downregulation of inflammatory marker genes. Additionally, we observed the improvement in locomotory behaviour among Withaferin A treatment adult zebrafish. In conclusion, S. aureus can infect zebrafish and induces toxicological effect. In comparison, the results from in vitro and in vivo experiments suggest that Withaferin A can be used for synergistic antibacterial, antibiofilm and anti-inflammatory activity to treat infections due S. aureus.

Biocontrol of Trichoderma gamsii induces soil suppressive and growth-promoting impacts and rot disease-protecting activities

Plant growth-promoting rhizosphere of associated fungi is often used to improve productivity and crop health. Some biocontrol fungi showed less disease protection efficiency due to environmental factors. Hence, the analysis of biocontrol fungi strains in the field is valuable to analyze their performance in the natural environment. The main objective of this study is to isolate the growth-promoting, rot disease-protecting activities of Trichoderma gamsii RH4 obtained from the rhizosphere of black gram (Vigna mungo). In this study, we evaluated the protective role of 13 fungal strains, including T. gamsii against Fusarium oxysporum in the laboratory experiment (antagonistic assay), greenhouse. The growth-promoting activity of the isolated 13 fungal strains was initially screened and the lytic property was assayed. The T. gamsii showed excellent growth-promoting and lytic properties. Lytic enzyme assays revealed a significant difference in the enzyme yield than other isolates (p < 0.05). The influence of selected plant-growth-promoting fungal strains on the suppression of F. oxysporum rot and wilt black gram was analyzed. Results revealed that these fungal isolates improved black gram growth in greenhouse and significantly reduced wilt and rot disease. The improved growth and yield registered in this study proved growth-promoting and biocontrol properties. The potent T. gamsii was applied in the open field and its effect on green gram was observed. The field trial experiment revealed several growth-promoting effects such as the weight and length of the root and shoot system. The isolated native T. gamsii has the potential to improve the biocontrol properties against rot disease.

Green Synthesis of Bioinspired Nanoparticles Mediated from Plant Extracts of Asteraceae Family for Potential Biological Applications

The Asteraceae family is one of the largest families in the plant kingdom with many of them extensively used for significant traditional and medicinal values. Being a rich source of various phytochemicals, they have found numerous applications in various biological fields and have been extensively used for therapeutic purposes. Owing to its potential phytochemicals present and biological activity, these plants have found their way into pharmaceutical industry as well as in various aspects of nanotechnology such as green synthesis of metal oxide nanoparticles. The nanoparticles developed from the plants of Asteraceae family are highly stable, less expensive, non-toxic, and eco-friendly. Synthesized Asteraceae-mediated nanoparticles have extensive applications in antibacterial, antifungal, antioxidant, anticancer, antidiabetic, and photocatalytic degradation activities. This current review provides an opportunity to understand the recent trend to design and develop strategies for advanced nanoparticles through green synthesis. Here, the review discussed about the plant parts, extraction methods, synthesis, solvents utilized, phytochemicals involved optimization conditions, characterization techniques, and toxicity of nanoparticles using species of Asteraceae and their potential applications for human welfare. Constraints and future prospects for green synthesis of nanoparticles from members of the Asteraceae family are summarized.

Molecular docking of monkeypox (mpox) virus proteinase with FDA approved lead molecules

BACKGROUND

Monkeypox virus (mpox) disease is caused by a double-stranded DNA virus from the Poxviridae family. The mpox virus showed structural similarity with smallpox virus disease. The recent outbreak of mpox infection in the rest of African countries causes public health issues of increased pandemic potential. Mpox virus is involved in the viral replication cycle through the biocatalytic reaction of precursor polyproteins cleavage.

OBJECTIVES

The main objective of the study was to analyze the molecular interactions between mpox and FDA-approved drugs.

METHODS

The primary and secondary structure of the protein was retrieved and FDA approved drug was screened using AutoDock. The best hit was analyzed and the molecular interactions were studied. Model validation analyzes the peptide, energy of hydrogen bonds, steric conflicts and bond planarity. Z-score was calculated using ProSA-web tool and the score tested the native fold from other alternative folds.

RESULTS

The confidence level of the submitted amino acids was> 80 % and the maximum confidence score for a single template was 98.2 %. The generated proteinase model was subjected to analyze the distribution of atoms and the using ERRAT server. The overall quality score was 88.535 and this value represents the amino acid percentage with anticipated error value and the value falling below the rejection limit. The Z-score of this study result was within the Z-score range (-4.17) validated for native enzymes. The binding pockets of the enzyme were determined in this study and two binding pockets were predicted using the automatic online tool using the web server. The selected FDA-approved drugs were ordered based on their minimum binding energy to the proteinase.

CONCLUSIONS

Molecular docking studies revealed the involvement of various hydrophobic interactions between FDA-approved drugs and amino acid residues of monkeypox virus proteinase.

Biocompatibility of Veratric Acid-Encapsulated Chitosan/Methylcellulose Hydrogel: Biological Characterization, Osteogenic Efficiency with In Silico Molecular Modeling

The limitations of graft material, and surgical sites for autografts in bone defects treatment have become a significant challenge in bone tissue engineering. Phytocompounds markedly affect bone metabolism by activating the osteogenic signaling pathways. The present study investigated the biocompatibility of the bio-composite thermo-responsive hydrogels consisting of chitosan (CS), and methylcellulose (MC) encapsulated with veratric acid (VA) as a restorative agent for bone defect treatment. The spectroscopy analyses confirmed the formation of CS/MC hydrogels and VA encapsulated CS/MC hydrogels (CS/MC-VA). Molecular analysis of the CS-specific MC decamer unit with VA complex exhibited a stable integration in the system. Further, Runx2 (runt-related transcription factor 2) was found in the docking mechanism with VA, indicating a high binding affinity towards the functional site of the Runx2 protein. The formulated CS/MC-VA hydrogels exhibited biocompatibility with the mouse mesenchymal stem cells, while VA promoted osteogenic differentiation in the stem cells, which was verified by calcium phosphate deposition through the von Kossa staining. The study results suggest that CS/MC-VA could be a potential therapeutic alternative source for bone regeneration.

Effective degradation of Chlortetracycline using dual bio catalyst

Chlortetracycline (CTC) degradation using potential microbial consortia or individual bacterial strains was useful method for improving bioremediation potential. The co-culture (Klebsiella pneumoniae CH3 and Bacillus amyloliquefaciens CS1) of bacterial strains have the ability to degrade chlortetracycline (91.8 ± 1.7%), followed by sulfamethoxazole (62.1 ± 1.2%) and amoxicillin (73.9 ± 3.3%). It was observed that the degradation potential was maximum after 10 days incubation, 8-10% inoculum, pH 7.5, and antibiotic concentration ranged from 150 to 200 mg/L. The initial concentrations of CTC significantly affected CTC degradation. In strain CH3, maximum biodegradation of CTC (99.4 ± 2.3%) was observed at 200 mg/L initial CTC concentrations. In CS1, maximum biodegradation of CTC was obtained at 150 mg/L concentration (80.5 ± 3.2%) after 10 days of culture. Alkaline pH was found to be suitable for the degradation of antibiotic than acidic range. After initial optimization by one factor at a time approach in free cells, the bacterial strains (CH3 and CS1) were co-immobilized. The co-immobilized bacterial cells showed improved degradation potential than free cells. To determine the biodegradation potential of immobilized cells, the selected strains were immobilized in polymer beads and treated with CTC with 175 mg/L initial concentration. The experimental results revealed that after 3 days of treatment the residual CTC concentration was 150.1 ± 3.2 mg/L and it decreased as 1.28 ± 0.01 mg/L after 10 days of treatment. The present study confirmed the effectiveness and feasibility of biodegradation ability of K. pneumoniae CH3 and B. amyloliquefaciens CS1 immobilized for CTC degradation in wastewater.

Biosorption of hazardous waste from the municipal wastewater by marine algal biomass

Lead is one of the highly toxic heavy metals causes various diseases even at very lower concentrations to human and affects eco-system. It is mainly released into the water through industrial activities. Phytoremediation is useful to degrade, reduce, metabolize and assimilate lead from wastewater. In this study, Turbinaria ornata was collected from the sea and dried biomass was used for biosorption of heavy metals. Adsorption of heavy metal was maximum after 100 min incubation with alga powder at acidic pH (4.5). The interactive effects of lead concentration, contact times, pH, biomass concentration and agitation speed was evaluated by a two-level full factorial design. Initial lead concentration, agitation speed and biomass concentration were the most important variables affecting lead removal (p < 0.001) were selected for optimization using central composite rotatable design. Lead removal was found to be maximum (99.8%) in optimized conditions: initial lead 99.8 mg/L, 250 rpm agitation speed and 16.2 g/L biomass concentrations. Municipal wastewater was collected and lead concentration (0.013 mg/L) and physiochemical factors were analyzed. Algal biomass removed >98.5% lead form the wastewater within 10 min in an optimized condition. The present study confirmed the potential application of T. ornata for the removal of lead from contaminated environment.

Evaluation of Nutritional Substances and Investigation of Antioxidant and Antimicrobial Potentials of Boerhavia diffusa with in Silico Molecular Docking

Boerhavia diffusa L. Nyctanginaceae (B. diffusa) is a medicinal herb commonly considered as a weed. The exploration of phytochemicals in different parts of B. diffusa with different solvents will create awareness, along with the suitable solvent and method for extraction of pharmaceutical compounds. Hence, the present study focuses on phytochemical analysis of B. diffusa leaves, stems, and roots in various solvents with hot and cold extraction. The decoctions performed well in most of the qualitative and quantitative tests, along with the DPPH assay. The aqueous extract showed a good result in the FRAP assay and ABTS assay. In the antimicrobial test, the B. diffusa root ethanol extract inhibited the growth of Pseudomonas aeruginosa and Staphylococcus aureus with zones of inhibition of about 8 mm and 20 mm at 200 µg concentration, respectively. Using a molecular docking approach, the top four ranked molecules from the crude extract of B. diffusa profiled from GC–MS spectroscopy in terms of growth inhibition of the pathogenic bacterium P. aeruginosa were selected; among them, 2-(1,2 dihydroxyethyl)-5-[[2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-3,4-dihydrochromen-6-yl]oxy]oxolane-3,4-diol exhibited the minimum binding score, revealing high affinity in complex. B. diffusa is highly nutritious, and the maceration and decoction extracts were similar except for the chloroform extract that was found to be weak.

GR15 peptide of S-adenosylmethionine synthase (SAMe) from Arthrospira platensis demonstrated antioxidant mechanism against H2O2 induced oxidative stress in in-vitro MDCK cells and in-vivo zebrafish larvae model

GR15 is a short molecule or peptide composed of aliphatic amino acids and possesses to have antioxidant properties. The GR15, ¹GGGAFSGKDPTKVDR¹⁵ was identified from the protein S-adenosylmethionine synthase (SAMe) expressed during the sulfur departed state of Arthrospira platensis (spirulina or cyanobacteria). The in-silico assessment and the structural features of GR15 showed its antioxidant potency. Real-time PCR analysis found the up-regulation of ApSAMe expression on day 15 against oxidative stress due to 10 mM H₂O₂ treatment in A. platensis (Ap). The antioxidant activity of GR15 was accessed by the cell-free antioxidant assays such as ABTS, SARS, HRAS and NO; the results showed dose-dependent antioxidant activity. The toxicity assay was performed in both in vitro and in vivo models, in which peptide does not exhibit any toxicity in MDCK cell and zebrafish embryos. The intercellular ROS reduction potential of GR15 peptide was also investigated in both in vitro and in vivo models including LDH assay, antioxidant enzymes (SOD and CAT), and fluorescent staining assay (DCFDA, Hochest and Acridine orange sting) was performed; the results showed that the GR15 peptide was effectively reduced the ROS level. Further, RT-PCR demonstrated that GR15 enhanced the antioxidant property and also up-regulated the antioxidant gene, thus reduced the ROS level in both in vitro and in vivo models. Based on the results obtained from this study, we propose that GR15 has the potential antioxidant ability; hence further research can be directed towards the therapeutic product or drug development against disease caused by oxidative stress.

Construction of Genomic Library and Screening of Edwardsiella tarda Immunogenic Proteins for Their Protective Efficacy Against Edwardsiellosis

Edwardsiella tarda is a severe aquaculture pathogen that can infect many hosts including humans, animals, and fish. Timely diagnosis and treatment are crucial for the control of edwardsiellosis in the aqua industry. By using rabbit polyclonal antibody, an expression gene library of virulent Edwardsiella tarda strain ED-BDU 1 isolated in south India was constructed and screened. The identified immune expressive proteins were characterized, and the corresponding coding sequences were cloned, expressed, and the purified recombinant proteins were used as antigens. The identified immunoreactive proteins namely HflC, HflK, and YhcI were studied for their immune protective potential in vivo by challenge experiments. The protective efficacy of HflC, HflK, and YhcI showed that the clearance of Edwardsiella from the host with ~ 60% survivability. Further, the immunoreactive proteins induce a strong immune response upon infection and elicit the significant production of IL-10, IFN-γ, Th1, and Th2 mediated mRNA expression and were therefore effective in vaccine production for edwardsiellosis.

Cholecalciferol and metformin protect against lipopolysaccharide-induced endothelial dysfunction and senescence by modulating sirtuin-1 and protein arginine methyltransferase-1

Endothelial cell activation through nuclear factor-kappa-B (NFkB) and mitogen-activated protein kinases leads to increased biosynthesis of pro-inflammatory mediators, cellular injury and vascular inflammation under lipopolysaccharide (LPS) exposure. Recent studies report that LPS up-regulated global methyltransferase activity. In this study, we observed that a combination treatment with metformin (MET) and cholecalciferol (VD) blocked the LPS-induced S-adenosylmethionine (SAM)-dependent methyltransferase (SDM) activity in Eahy926 cells. We found that LPS challenge (i) increased arginine methylation through up-regulated protein arginine methyltransferase-1 (PRMT1) mRNA, intracellular concentrations of asymmetric dimethylarginine (ADMA) and homocysteine (HCY); (ii) up-regulated cell senescence through mitigated sirtuin-1 (SIRT1) mRNA, nicotinamide adenine dinucleotide (NAD+) concentration, telomerase activity and total antioxidant capacity; and (iii) lead to endothelial dysfunction through compromised nitric oxide (NOx) production. However, these LPS-mediated cellular events in Eahy926 cells were restored by the synergistic effect of MET and VD. Taken together, this study identified that the dual compound effect inhibits LPS-induced protein arginine methylation, endothelial senescence and dysfunction through the components of epigenetic machinery, SIRT1 and PRMT1, which is a previously unidentified function of the test compounds. In silico results identified the presence of vitamin D response element (VDRE) sequence on PRMT1 suggesting that VDR could regulate PRMT1 gene expression. Further characterization of the cellular events associated with the dual compound challenge, using gene silencing approach or adenoviral constructs for SIRT1 and/or PRMT1 under inflammatory stress, could identify therapeutic strategies to address the endothelial consequences in vascular inflammation-mediated atherosclerosis.

Sequestration of toxic Pb(II) ions using ultrasonic modified agro waste: Adsorption mechanism and modelling study

Treating the effluents from industries by using biological and agricultural wastes is an emerging field of research. In this study, three different biosorbents are prepared from tamarind seeds such as; raw, sulphuric acid-modified and ultrasonic-assisted surface-modified tamarind seed powder has been utilized to expel the Pb (II) ions from synthetic solution. The surface characteristics of the newly synthesized raw and surface modified agro-waste biomass were studied by FTIR and SEM. An experimental study was carried out to investigate the effect of different parameters on adsorption of Pb(II) ions using raw, sulphuric acid-modified and ultrasonic-assisted surface-modified tamarind seeds. The maximum Pb(II) ions adsorption was found at pH - 6.0, temperature - 303 K, biosorbent dosage - 3.5 g/L and contact time - 60 min for raw tamarind seeds and 30 min for sulphuric acid-modified and ultrasonic-assisted surface-modified tamarind seeds. The adsorption mechanism was described by Langmuir isotherm and pseudo-first order kinetic model. Among the three biosorbents, ultrasonic-assisted surface-modified tamarind seeds show higher adsorption capacity (18.86 mg/g) of Pb(II) ions removal from the synthetic solution. The thermodynamic study declared that the present Pb(II) ions adsorption onto the prepared biosorbents was spontaneous, exothermic and followed physical adsorption process. Results have shown that tamarind seed was found to be the best adsorbent in the expulsion of Pb(II) ions from the wastewater environment.

Shotgun whole genome sequencing of drug-resistance Streptococcus anginosus strain 47S1 isolated from a patient with pharyngitis in Saudi Arabia

BACKGROUND

Streptococcus anginosus is an emergence opportunistic pathogen that colonize the human upper respiratory tract (URT), S. anginosus alongside with S. intermedius and S. constellatus, members of S. anginosus group, are implicated in several human infections. However, our understanding this bacterium to the genotype level with determining the genes associated with pathogenicity and antimicrobial resistance (AMR) is scarce. S. anginosus 47S1 strain was isolated from sore throat infection, the whole genome was characterized and the virulence & AMR genes contributing in pathogenicity were investigated.

METHODOLOGY

The whole genome of 47S1 was sequenced by Illumina sequencing technology. Strain 47S1 genome was de novo assembled with different strategies and annotated via PGAP, PROKKA and RAST pipelines. Identifying the CRISPR-Cass system and prophages sequences was performed using CRISPRloci and PhiSpy tools respectively. Prediction the virulence genes were performed with the VFDB database. AMR genes were detected in silico using NCBI AMRFinderPlus pipeline and CARD database and compared with in vitro AST findings.

RESULTS

β-hemolytic strain 47S1 was identified with conventional microbiology techniques and confirmed by the sequences of 16S rRNA gene. Genome of 47S1 comprised of 1981512 bp. Type I-C CRISPR-Cas system and 4 prophages were detected among the genome of 47S1. Several virulence genes were predicted, most of these genes are found in other pathogenic streptococci, mainly lmb, pavA, htrA/degP, eno, sagA, psaA and cpsI which play a significant role in colonizing, invading host tissues and evade form immune system. In silico AMR findings showed that 47S1 gnome harbors (tetA, tetB &tet32), (aac(6')-I, aadK &aph(3')-IVa), fusC, and PmrA genes that mediated-resistance to tetracyclines, aminoglycosides, fusidic acid, and fluoroquinolone respectively which corresponds with in vitro AST obtained results. In conclusion, WGS is a key approach to predict the virulence and AMR genes, results obtained in this study may contribute for a better understanding of the opportunistic S. anginosus pathogenicity.

Environmental photochemistry in Solanum trilobatum mediated plasmonic nanoparticles as a probe for the detection of Cd2+ ions in water

Nowadays world deals with a lot of environmental troubles out of which water pollution is very dangerous. Water gets contaminated by heavy metal ions is a universal problem which needs suitable consideration to keep up the quality of the water. It will be advantageous that an easy device can be detecting the concentration of heavy metal ions in water. Here, a contaminant, cadmium from industrial affluent into water is considered and focused. Gold nanoparticles (AuNPs) have been synthesized by Solanum trilobatum leaf extract and its applications of antifungal and sensing activity was reported here. The influences of different concentration of these reducing agent on the synthesis of AuNPs (G5 and G10) have been evaluated. The structural, optical, vibrational, morphological and compositional properties of the AuNPs were studied through XRD, UV-vis spectra, FTIR, HRTEM and EDAX analysis. The optical studies showed surface plasmon absorbance peak at 526 nm. It shows that the absorbance of the peak becomes narrow with a higher concentration of leaf extract. XRD results showed the average size of the AuNPs was 8 nm. It also confirmed the high crystallinity of nanoparticles. FTIR exposes that amine and carboxyl groups may be involved in the stabilization and reduction mechanism. TEM pictures of both G10 and G5 demonstrate merely spherical nanoparticles. This morphology control is taken place owing to the adsorbed amine and carboxyl groups onto the gold nanoparticles cap the particles and improve the stability. The presence of gold elements in the sample was identified with the help of EDAX. The sensitivity of the system towards various Cd²⁺ concentrations was measured as 0.058/mM for G5 and 0.095/mM for G10. The prepared nanoparticles produced highest zone of inhibition (ZOI) of 17.5 mm and 19 mm against human being pathogenic fungi Aspergillus Flavus and Candida albicans respectively. Here, small sized spherical nanoparticles showed good antifungal activity.

Synthesis and characterization of magnetite carbon nanocomposite from agro waste as chromium adsorbent for effluent treatment

The waste water released from industries which contain pollutants like heavy metals, dyes and other toxic chemicals brings numerous harms to the ecosystem and humans. Nowadays the nanocomposites based technologies are effectively used for environmental remediation. In the present study, hexavalent chromium was removed from the industrial effluent using magnetite carbon nanocomposite. The nanocomposite composed of highly porous carbon and iron oxide nanoparticles prepared by using agrowastes (sugarcane bagasse and orange peel extract). Iron oxide nanoparticles (FeONPs) formation was confirmed by UV-visible spectroscopy; incorporation of magnetite with highly porous carbon was established by Fourier Transforms Infrared Spectroscopy and X-ray Diffraction Spectroscopy. Morphological features of magnetite nanoparticles and highly porous carbon were analyzed using Scanning Electron Microscope and Transmission Electron Microscope. Magnetic properties analyzed by Vibrating Sample Magnetometer revealed magnetite carbon nanocomposite exhibited better Ms value than highly porous carbon. The concentration of Cr⁶⁺ in treated effluent was determined using Atomic Absorption Spectroscopy. Pseudo-second order equation fitted with kinetics and the Langmuir monolayer favors for isotherm. This study reveals efficiency in Cr⁶⁺ removal from effluent using magnetite carbon nanocomposites which extends their application in waste water treatment.

Antimicrobial activities of novel class of dispirooxindolopyrrolidine grafted indanedione hybrid heterocycles against carbapenemase producing Klebsiella pneumoniae (CKP)

BACKGROUND

Aggressive antimicrobial infections together with an increasing in resistance to antimicrobial medications cause a threat to immunocompromised individual. In this context, spiro compounds play an important role in drug discovery research due to their diverse biological activities including antimicrobial activity which is well documented in literature, because of their unique structural properties allow for easy interaction with the target enzyme of the biological system. This biological precedent encouraged us to design and synthesis of novel dispirooxindolopyrrolidine hybrid heterocycles via multicomponent cycloaddition protocol.

MATERIALS AND METHODS

Novel class of dispirooxindolopyrrolidine hybrid heterocycles has been synthesized by multicomponent 1,3-dipolar cycloaddition methodology and the structure of the products was determined through spectroscopic analysis. The synthesized organic compounds were evaluated for their antimicrobial activities using sensitivity test with standard agar well diffusion method.

RESULTS

The synthesized new class of dispiropyrrolidine embedded indandione hybrids showed significant antimicrobial activity against carbapenemase producing Klebsiella pneumoniae (CKPs) isolated from hospital patients. Compound that possessing chlorine substituted on the aryl ring exhibited more potent antimicrobial activities and the zone of inhibitions was observed between 7.00 ± 0.09 and 18.40 ± 0.70 mm. The MIC value of compound 4b was 0.030 mg/mL against tested CKP.

CONCLUSION

A new class of dispiropyrrolidine heterocyclic hybrids were synthesized in good to excellent yield employing multicomponent 1,3-dipolar cycloaddition strategy. Among them, compounds bearing 4-chloro substituted on the aryl ring exhibited notable activity just equal to the standard drug, ciprofloxacin. Future studies are needed to elucidate the pharmacological properties of new compounds that were synthesized in our laboratory for the novel therapeutic development.

Isolation and characterization of novel Streptomyces strain from Algeria and its in-vitro antimicrobial properties against microbial pathogens

BACKGROUND

The constant development of microbial resistance to the traditional antimicrobial agents and the emergence of new infectious diseases justify the urgent need for new effective antimicrobial molecules. However, the irrational use of antibiotics increases microbial resistance dramatically and along with that the frequency of mortality associated with infections is higher. Therefore, to combat the antimicrobial resistance, the screening of compounds with novel chemical structures is essential. This study intended to determine the antimicrobial potential of Streptomyces GLD22 strain isolated from Algeria.

METHODS

The characterization of Streptomyces strain GLD22 was performed by physiological, biochemical and molecular tests. The antimicrobial activity was tested by the well diffusion method and the minimum inhibitory concentration value calculation were performed using broth micro dilution technique. The extracellular metabolites profiling was done using GC-MS.

RESULTS

Physiological, biochemical and phylogenetic analysis confirmed that the strain GLD22 showed maximum identity towards Streptomyces species. The extra cellular metabolites revealed their antimicrobial activity at 1 mg/ml for Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli, whereas Staphylococcus aureus, Bacillus cereus and Bacillus subtilis documented 0.5, 1 and 1 mg/ml respectively. GC-MS analysis confirmed that 2-tert-butyl-4,6-bis(3,5-di-tert-butyl-4-hydroxybenzyl) phenol, Dibutyl phthalate and Cyclo(leucyloprolyl) were the major drug molecules present in the extract.

CONCLUSION

The novel Streptomyces strain GLD22 recovered from the Gueldaman cave of Algeria showed better antimicrobial activity towards both Gram positive and Gram negative pathogens. Interestingly, the MIC values were comparable with the standard drug molecules. In addition, the identification of active metabolites present in the crude extracts was an advantage.

Nanotechnology based solutions to combat zoonotic viruses with special attention to SARS, MERS, and COVID 19: Detection, protection and medication

Zoonotic viruses originate from birds or animal sources and responsible for disease transmission from animals to people through zoonotic spill over and presents a significant global health concern due to lack of rapid diagnostics and therapeutics. The Corona viruses (CoV) were known to be transmitted in mammals. Early this year, SARS-CoV-2, a novel strain of corona virus, was identified as the causative pathogen of an outbreak of viral pneumonia in Wuhan, China. The disease later named corona virus disease 2019 (COVID-19), subsequently spread across the globe rapidly. Nano-particles and viruses are comparable in size, which serves to be a major advantage of using nano-material in clinical strategy to combat viruses. Nanotechnology provides novel solutions against zoonotic viruses by providing cheap and efficient detection methods, novel, and new effective rapid diagnostics and therapeutics. The prospective of nanotechnology in COVID 19 is exceptionally high due to their small size, large surface-to-volume ratio, susceptibility to modification, intrinsic viricidal activity. The nano-based strategies address the COVID 19 by extending their role in i) designing nano-materials for drug/vaccine delivery, ii) developing nano-based diagnostic approaches like nano-sensors iii) novel nano-based personal protection equipment to be used in prevention strategies.This review aims to bring attention to the significant contribution of nanotechnology to mitigate against zoonotic viral pandemics by prevention, faster diagnosis and medication point of view.

Oxidative stress induced antioxidant and neurotoxicity demonstrated in vivo zebrafish embryo or larval model and their normalization due to morin showing therapeutic implications

AIMS

The study examined that morin as possible antioxidant and neuroprotective due to oxidative stress (H₂O₂) in zebrafish larval model.

MATERIALS AND METHODS

Zebrafish larvae were induced with oxidative stress using H₂O₂ at 1 mM; their behavioural changes were assessed through partition preference and horizontal compartment test. The head section without eyes and yolk sac of zebrafish larvae were employed for enzyme assays such as SOD, CAT, Thiobarbituric acid reactive substances assay, reduced glutathione, glutathione peroxidase activity, glutathione S transferase, Acetylcholinesterase activity and nitrate levels. Also, intracellular ROS and apoptosis in larval head was detected by DCFDA and acridine orange staining followed by gene expression studies.

KEY FINDINGS

Morin exposure was not harmful to the larvae at concentration between 20 and 60 μM, but it caused non-lethal deformity between 80 and 100 μM. In the partition test, zebrafish embryos treated with H₂O₂ showed cognitive impairment, whereas the morin-treated groups showed an improved behavioural activity. The study also found that restoring antioxidant enzymes and reduced lipid peroxidation which had a neuroprotective impact. Inhibition of NO overproduction and increased AChE activity were also shown to reduce the neuronal damage. Apoptosis and intracellular ROS levels were reduced in larvae when it was co-incubated with morin. Morin treatment up regulated the antioxidant enzymes against oxidative stress.

SIGNIFICANCE

Morin provides protection against H₂O₂ induced oxidative stress through a cellular antioxidant defence mechanism by up-regulating gene expression, thus increasing the antioxidant activity at cellular or organismal stage.

NV14 from serine O-acetyltransferase of cyanobacteria influences the antioxidant enzymes in vitro cells, gene expression against H2 O2 and other responses in vivo zebrafish larval model

In this study, we have identified a novel peptide NV14 with antioxidative functions from serine O-acetyltransferase (SAT) of Artrospira platensis (Ap). The full sequence of ApSAT and its derived NV14 peptide "NVRIGAGSVVLRDV" (141-154) was characterized using bioinformatics tools. To address the transcriptional activity of ApSAT in response to induce generic oxidative stress, the spirulina culture was exposed to H₂ O₂ (10 mM). The ApSAT expression was studied using RT-PCR across various time points and it was found that the expression of the ApSAT was significantly upregulated on Day 15. The in vitro cytotoxicity assay against NV14 was performed in human dermal fibroblast cells and human blood leukocytes. Results showed that NV14 treatment was non-cytotoxic to the cells. Besides, in vivo treatment of NV14 in zebrafish larvae did not exhibit the signs of developmental toxicity. Further, the in vitro antioxidant assays enhanced the activity of the antioxidant enzymes, such as SOD and CAT, due to NV14 treatment; and also significantly reduced the MDA levels, while increasing the superoxide radical and H₂ O₂ scavenging activity. The expression of antioxidant enzyme genes glutathione peroxidase, γ-glutamyl cysteine synthase, and glutathione S-transferase were found to be upregulated in the NV14 peptide pretreated zebrafish larvae when induced with generic oxidative stress, H₂ O₂ . Overall, the study showed that NV14 peptide possessed potent antioxidant properties, which were demonstrated over both in vitro and in vivo assays. NV14 enhanced the expression of antioxidant enzyme genes at the molecular level, thereby modulating and reversing the cellular antioxidant balance disrupted due to the H₂ O₂ -induced oxidative stress.

Pharmacological importance of TG12 from tachykinin and its toxicological behavior against multidrug-resistant bacteria Klebsiella pneumonia

Development of antimicrobial drugs against multidrug-resistant (MDR) bacteria is a great focus in recent years. TG12, a short peptide molecule used in this study was screened from tachykinin (Tac) protein of an established teleost Channa striatus (Cs) transcriptome. Tachykinin cDNA has 345 coding sequence, that denotes a protein contained 115 amino acids; in which a short peptide (TG12) was identified at 83-94. Tachykinin mRNA upregulated in C. striatus treated with Aeromonas hydrophila and Escherichia coli lipopolysaccharide (LPS). The mRNA up-regulation was studied using real-time PCR. The up-regulation tachykinin mRNA pattern confirmed the immune involvement of tachykinin in C. striatus during infection. Further, the identified peptide, TG12 was synthesized and its toxicity was demonstrated in hemolytic and cytotoxic assays using human erythrocytes and human dermal fibroblast cells, respectively. The toxicity study exhibited that the toxicity of TG12 was similar to negative control, phosphate buffer saline (PBS). Moreover, the antibiogram of TG12 was active against Klebsiella pneumonia ATCC 27736, a major MDR bacterial pathogen. Further, the antimicrobial activity of TG12 against pathogenic bacteria was screened using minimum inhibitory concentration (MIC) and anti-biofilm assays, altogether TG12 showed potential activity against K. pneumonia. Fluorescence assisted cell sorter flow cytometer analysis (FACS) and field emission scanning electron microscopy (FESEM) was carried on TG12 with K. pneumonia; the results showed that TG12 significantly reduced K. pneumonia viability as well as TG12 disrupt its membrane. In conclusion, TG12 of CsTac is potentially involved in the antibacterial immune mechanisms, which has a prospectus efficiency in pharma industry against MDR strains, especially K. pneumonia.

Green synthesis of lignin nanorods/g-C3N4 nanocomposite materials for efficient photocatalytic degradation of triclosan in environmental water

Triclosan (TCS) is a common anti-microbial ingredient in pharmaceutical and personal care products. The usage of TCS was banned by the United States Food and Drug Administration (in 2016) due to its potential health risks. However, TCS has been frequently detected in the aquatic environment. Therefore, it is vital to design low-cost and highly efficient photocatalysts to enhance TCS's photocatalytic degradation in wastewater treatment to eliminate its toxicity to environmental health. In this study, we developed a highly efficient catalyst by incorporating lignin nanorods (LNRs) into graphitic carbon nitride (GCN) nanomaterials as green LNRs/GCN-based nanocomposite photocatalysts for the effective degradation of TCS in waters. LNRs/GCN nanosheets (NSs) and LNRs/GCN-NRs based nanocomposite materials were prepared using a simple wet-impregnation method. The surface morphology and optical properties of as-synthesized materials were well-characterized using FE-SEM, XRD, XPS, and UV-DRS. The photocatalyst (LNRs/GCN-NRs) material showed maximum TCS degradation efficiency of 99.9% and a high rate constant of 0.0661 min^-1 under pH-10 with crucial reactive spices (OH and O₂^-), and excellent cycling performance (over five cycles) within 90 min of UV-light illumination. LNRs/GCN-NRs nanocomposite indicated enhanced photocatalytic performances for TCS degradation due to its strong synergistic effect between LNRs and GCN-NRs as bifunctional catalyst substrate morphology with efficient bandgap energy and accessible active sites compared to LNRs/GCN-NSs. Therefore, LNRs/GCN-NRs nanocomposite was observed to be a highly-active, low-cost, stable, eco-friendly, and efficient photocatalyst for complete degradation of TCS under UV-light irradiation.

Hepatoprotective effect of selected isoandrographolide derivatives on steatotic HepG2 cells and High Fat Diet fed rats

Non-alcoholic Fatty Liver Disease (NAFLD) is one of the growing epidemics of the globe. This study was aimed to evaluate the anti-NAFLD effect of selected IAN derivatives using in silico, in vitro and in vivo models. In silico tools viz., DataWarrior, SwissADME and Gaussian 09 were used to predict the pharmacokinetic properties and electronic distribution patterns of the derivatives; docking analysis was done with Autodock against PPARα. Toxicities of the derivatives were assessed in HepG2 cells using MTT assay. Anti-NAFLD efficacies of the derivatives were assessed in free fatty acid induced steatotic HepG2 cells. In vivo anti-NAFLD effect of active isoandrographolide (IAN) derivative, 19-propionyl isoandrographolide (IAN-19P) was assessed in High Fat Diet fed rats. In silico and in vitro studies indicated that IAN-19P showed improved drug-likeness and drug score. The toxicity of IAN-19P to HepG2 cells was comparatively less than IAN and other derivatives. In free fatty acid induced steatotic HepG2 cells, treatment with IAN-19P significantly lowered intracellular triglyceride content and leakage of LDH and transaminases. Treating High Fat Diet fed animals with IAN-19P significantly lowered plasma lipids, transaminases, LDH and GGT levels. The treatment with IAN-19P upregulated the expressions of PPARα and CPT-1. IAN-19P did not produce any noticeable adverse effect till 2 g/kg concentration in acute and 250 mg/kg concentration in subacute toxicity studies. This study indicated the beneficial effect of IAN-19P for the treatment of NAFLD; however robust investigations are needed to establish the potential of IAN-19P to treat NAFLD.

Effective degradation of tetracycline by manganese peroxidase producing Bacillus velezensis strain Al-Dhabi 140 from Saudi Arabia using fibrous-bed reactor

A tetracycline degrading bacterial strains was characterized from the municipal sludge and detected its ability to produce manganese peroxidase. The molecular weight of manganese peroxidase was determined as 46 kDa after Biogel P-100 gel filtration column chromatography purification. Maximum tetracycline degradation was observed with the manganese peroxidase from the strain Bacillus velezensis Al-Dhabi 140 and the optimum degradation process was studied. Optimization revealed the maximum removal efficacy was obtained as 87 mg/L at initial tetracycline concentration 143.75 mg/L, pH 6.94 and 8.04% inoculum. Consequently, fibrous bed reactor containing the culture of B. velezensis Al-Dhabi 140 in fibrous matrix was formed to transform tetracycline in synthetic wastewater. The transformed product of tetracycline from the fibrous bed reactor was evident by the activity of ligninolytic enzymes produced by B. velezensis Al-Dhabi 140 in reactor. The decreased level of antibacterial potency was obtained after 10 days. The zone of inhibition was 24 ± 1 mm after 1 day and it decreased as 9 ± 1 mm after 10 days. Based on the findings, fibrous bed B. velezensis Al-Dhabi 140 could be an efficient strain for tetracycline removal from artificial wastewater, even from natural wastewater.

Removal of nitrogen from wastewater of date processing industries using a Saudi Arabian mesophilic bacterium, Stenotrophomonas maltophilia Al-Dhabi-17 in sequencing batch reactor

The main aim of the present study was to assess the technical feasibility of nutrients removal from the wastewater from the date processing industries in sequencing batch reactor. Heterotrophic nitrifying and aerobic denitrifying bacteria were isolated from the soil sediment samples. The bacterial strain Al-Dhabi-17 effectively removed nutrients than other isolates from the wastewater and characterized as Stenotrophomonas maltophilia Al-Dhabi-17. The nutrient removal efficacy was improved by optimizing process parameters. Removal of NH₄⁺ from the medium reached 42% within 60 h of cultivation and the nitrification rate was 111 ± 3.1 mg after 24 h. After 96 h, NO₃^- reached 6 ± 0.4 mg/mL concentration. The strain S. maltophilia Al-Dhabi-17 showed the ability to utilize NH₄⁺ ranged between 100 and 300 mg/L. The supplemented sucrose, glucose and date molasses reached maximum nitrification process after 72 h (p < 0.05). Reduction of NH₄⁺ -N reached 73.4% within 48 h time in the medium supplemented with date molasses. Nutrient removal was observed in the broad pH range (6.0-8.5) and maximum nutrient removal achieved at alkaline range (p < 0.05). Sequencing batch reactor was fed with wastewater and nutrient removal was analyzed under optimized condition. The associated chemical oxygen demand, phosphate and total nitrogen removal efficiencies for the suspended growth sequencing batch reactor were 96.5%, 97.9% and 88.4%, respectively. The sequencing batch reactor inoculated with S. maltophilia Al-Dhabi-17 showed promising for nitrogen removal.

Medicinal Plants, Phytochemicals, and Herbs to Combat Viral Pathogens Including SARS-CoV-2

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome corona virus-2 (SARS-CoV-2), is the most important health issue, internationally. With no specific and effective antiviral therapy for COVID-19, new or repurposed antiviral are urgently needed. Phytochemicals pose a ray of hope for human health during this pandemic, and a great deal of research is concentrated on it. Phytochemicals have been used as antiviral agents against several viruses since they could inhibit several viruses via different mechanisms of direct inhibition either at the viral entry point or the replication stages and via immunomodulation potentials. Recent evidence also suggests that some plants and its components have shown promising antiviral properties against SARS-CoV-2. This review summarizes certain phytochemical agents along with their mode of actions and potential antiviral activities against important viral pathogens. A special focus has been given on medicinal plants and their extracts as well as herbs which have shown promising results to combat SARS-CoV-2 infection and can be useful in treating patients with COVID-19 as alternatives for treatment under phytotherapy approaches during this devastating pandemic situation.

Emerging paradigms of viral diseases and paramount role of natural resources as antiviral agents

In the current scenario, the increasing prevalence of diverse microbial infections as well as emergence and re-emergence of viral epidemics with high morbidity and mortality rates are major public health threat. Despite the persistent production of antiviral drugs and vaccines in the global market, viruses still remain as one of the leading causes of deadly human diseases. Effective control of viral diseases, particularly Zika virus disease, Nipah virus disease, Severe acute respiratory syndrome, Coronavirus disease, Herpes simplex virus infection, Acquired immunodeficiency syndrome, and Ebola virus disease remain promising goal amidst the mutating viral strains. Current trends in the development of antiviral drugs focus solely on testing novel drugs or repurposing drugs against potential targets of the viruses. Compared to synthetic drugs, medicines from natural resources offer less side-effect to humans and are often cost-effective in the productivity approaches. This review intends not only to emphasize on the major viral disease outbreaks in the past few decades and but also explores the potentialities of natural substances as antiviral traits to combat viral pathogens. Here, we spotlighted a comprehensive overview of antiviral components present in varied natural sources, including plants, fungi, and microorganisms in order to identify potent antiviral agents for developing alternative therapy in future.

Conversion of waste frying oil into biodiesel using recoverable nanocatalyst based on magnetic graphene oxide supported ternary mixed metal oxide nanoparticles

The magnetic graphene oxide (GO) supported with heterogeneous ternary mixed metal oxide (MMO) was used as nanocatalyst to enhance the conversion of waste frying oil (WFO) triglycerides to biodiesel via esterification process. In this regard, acidic MGO was modified with three basic metal cations of cerium, zirconium, and strontium oxides to produce heterogeneous MGO@MMO nanocatalyst. The nanocatalyst was characterized by FESEM, TEM, EDX and FTIR. The influence of different parameters such as catalyst material ratio, methanol to oil ratio, contact time, and reaction temperature was studied. Based on the results of effecting parameters, the MGO@MMO nanocatalyst converted WFO to biodiesel with a yield 94%, a reaction time of 90 min, methanol to oil ratio (8:1), and a temperature of 60 °C. Esterification mechanism indicated the MGO@MMO nanocatalyst having both binary Brønsted acid-base sites that increased the conversion yields as compared to MGO and MMO at low temperatures.

Biochemical analysis of leptospiral LPS explained the difference between pathogenic and non-pathogenic serogroups

Lipopolysaccharide (LPS) is the major surface antigen of Leptospira. In this study, the genes involved in the LPS biosynthesis were analyzed and compared by bioinformatics tools. Also, the chemical composition analysis of leptospiral lipopolysaccharides (LPS) extracted from 5 pathogenic serovars like Autumnalis, Australis, Ballum, Grippotyphosa, Pomona, and the nonpathogenic serovar Andamana was performed. Methods used were Limulus amebocyte lysate assay (LAL), gas chromatography-mass spectrometry (GC-MS), fourier transform infrared spectroscopy (FT-IR), and nuclear magnetic resonance spectroscopy (NMR). LAL assay showed a significantly higher level of endotoxicity among pathogenic serovars (~0.490 EU/mL) than that of nonpathogenic Andamana (~0.102 EU/mL). FAMES analysis showed the presence of palmitic acid (C16:0), hydroxy lauric acid (3-OH-C12:0), and oleic acid (C18:0). Palmitoleic acid (C16: 1), and 3- hydroxy palmitate (3-OH-C16:0) was detected only in pathogenic serovars. In contrast myristoleic acid (C14:1) and stearic acid (C18:0) were present in Andamana. FTIR analysis revealed C-O-C stretch of esters, 3°ROH functional groups and carbohydrate vibration range were similar among pathogenic serovars. The NMR analysis reveals similarity for 6 deoxy sugars and methyl groups of Autumnalis, Australis, and Ballum. Further, the presence of palmitoleic acid and 3-hydroxy palmitate may be the significant pathogen-associated predisposing factor. This mediates high osmolarity glycerol (HOG) mediated stress response in leptospiral LPS mediated pathogenesis.

Intracellular ROS scavenging and antioxidant regulation of WL15 from cysteine and glycine-rich protein 2 demonstrated in zebrafish in vivo model

Antioxidant peptides are naturally present in food, especially in fishes, and are considered to contain rich source of various bioactive compounds that are structurally heterogeneous. This study aims to identify and characterize the antioxidant property of the WL15 peptide, derived from Cysteine and glycine-rich protein 2 (CSRP2) identified from the transcriptome of a freshwater food fish, Channa striatus. C. striatus is already studied to contain high levels of amino acids and fatty acids, besides traditionally known for its pharmacological benefits in the Southeast Asian region. In our study, in vitro analysis of WL15 peptide exhibited strong free radical scavenging activity in 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), superoxide anion radical and hydrogen peroxide (H2O2) scavenging assay. Further, to evaluate the cytotoxicity and dose-response, the Human dermal fibroblast (HDF) cells were used. Results showed that the treatment of HDF cells with varying concentrations (10, 20, 30, 40 and 50 μM) of WL15 peptide was not cytotoxic. However, the treatment concentrations showed enhanced antioxidant properties by significantly inhibiting the levels of free radicals. For in vivo assessment, we have used zebrafish larvae for evaluating the developmental toxicity and for determining the antioxidant property of the WL15 peptide. Zebrafish embryos were treated with the WL15 peptide from 4 h of post-fertilization (hpf) to 96 hpf covering the embryo-larval developmental period. At the end of the exposure period, the larvae were exposed to H2O2 (1 mM) for inducing generic oxidative stress. The exposure of WL15 peptide during the embryo-larval period showed no developmental toxicity even in higher concentrations of the peptide. Besides, the WL15 peptide considerably decreased the intracellular reactive oxygen species (ROS) levels induced by H2O2 exposure. WL15 peptide also inhibited the H2O2-induced caspase 3-dependent apoptotic response in zebrafish larvae was observed using the whole-mount immunofluorescence staining. Overall results from our study showed that the pre-treatment of WL15 (50 μM) in the H2O2-exposed zebrafish larvae, attenuated the expression of activated caspase 3 expressions, reduced Malondialdehyde (MDA) levels, and enhanced antioxidant enzymes, including superoxide dismutase (SOD) and catalase (CAT). The gene expression of antioxidant enzymes such as glutathione S-transferase (GST), glutathione peroxide (GPx) and γ-glutamyl cysteine synthetase (GCS) was found to be upregulated. In conclusion, it can be conceived that pre-treatment with WL15 could mitigate H2O2-induced oxidative injury by elevating the activity and expression of antioxidant enzymes, thereby decreasing MDA levels and cellular apoptosis by enhancing the antioxidant response, demonstrated by the in vitro and in vivo experiments.

Adverse Effect of Antibiotics Administration on Horse Health: An Overview

Antibiotics-based therapy plays a paramount role in equine medicine because of their potential pharmacokinetics and pharmacodynamics properties. Conventional antibiotics show bacteriostatic and bactericidal properties by interfering bacterial cell wall and protein synthesis as well as inhibiting RNA polymerase, DNase 1, and DNA gyrase. Antibiotics are extensively used not only for the treatment of varied bacterial infections but also the prevention of postoperative and secondary infections. Surprisingly, antibiotics such as sulfonamides or trimethoprim/sulfonamide combinations, benzylpenicillin, cefquinome, fluphenazine, enrofloxacin, and sodium ceftriaxone cause detrimental effects on horses' health, namely, diarrhea, colitis, nephrotoxicity, ototoxicity, dysrhythmia, arthropathy, ataxia, anorexia, seizures, peripheral neuropathy, and certain neurologic abnormalities. Therefore, in equine practice, it is essential to optimize and analyze the combinations, formulations, route of administration, and dosages of certain antibiotics before administration. This review overviews the mode of actions and pharmacologic attributes of certain antibiotics, commonly used toward the treatment of disparate horse diseases. Most importantly, special emphasis was given to spotlight the potential adverse effects encountered during the administration of antibiotics as therapeutics in horses.