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This study develops environmentally benign capping technique to synthesize nanoparticles of Curcuma longa-coated titanium dioxide (CR-TiO 2 ) from titanium isopropoxide by utilizing the extract of Rosa rubiginosa flowers as reducing and chelating agent. The biogenically synthesized nanoparticles revealed excellent anti-bacterial, electrochemical, and photocatalytic properties due to the presence of porous TiO 2 nanostructures. The sharp peaks by XRD pattern showed the crystallinity and phase purity of TiO 2 nanoparticles. BET analysis proved mesoporous nature of the materials with specific surface area of 134 m 2  g -1 . The vibrational spectra suggest hydroxyl groups from flavonoids of Curcuma longa acting as functionalizing agent for TiO 2 nanoporous structures with visible luminescence, which is proven in fluorescence spectra and is applicable for photocatalytic studies. The anti-bacterial studies showed good inference on TiO 2 nanoparticles against Pseudomonas auruginosa and proved it to be an excellent antipseudomonal agent with the oxidative potential. The maximum degradation of phenol red dye in the presence of TiO 2 under visible light conditions was observed. The supercapacitor fabricated using the biogenic TiO 2 three-electrode system exhibited a specific capacitance of 128 Fg -1 (10 mV s -1 ), suggesting it as an excellent electrode material. The LSV curve at 50 mV s -1 scan rate showed that oxygen reduction potential (ORR) of CR-TiO 2 electrodes was 121 mV. The present study is a new application of nanoparticles in sustainability consideration of the environment as well as a solution to the power crisis with fewer limitations. The well-distinguished antidiabetic and BSA denaturation potential suggests that these porous TiO 2 nanostructures can be useful for drug delivery as glucose inhibitors and oral anti-inflammatory drugs with the restriction of adverse side effects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The current research was designed to investigate the antibacterial activity of probiotic bacteria mediated cadmium oxide nanoparticles (CdO NPs) on common fish pathogenic bacteria like Serratia marcescens, Aeromonas hydrophila, Vibrio harveyi, and V. parahaemolyticus. CdO NPs were synthesized using probiotic bacteria as follows: Lactobacillus species with different precursor of cadmium sulfate concentrations (5, 10, and 20 mM). The average crystalline sizes of the CdO NPs were determined based on the XRD patterns using the Debye-Scherrer equation for different precursor concentrations. Specifically, sizes of 40, 48, and 67 nm were found at concentrations of 5, 10, and 20 mM, respectively. The antibacterial efficacy of CdO NPs was estimated using a well diffusion assay, which demonstrated the best efficacy of 20 mM CdO NPs against all pathogens. AFM analysis of nanoparticle-treated and untreated biofilms was performed to further validate the antibacterial effect. Antibacterial activity of CdO nanoparticles synthesized at varying concentrations (5, 10, and 20 mM) against fish pathogens (S. marcescens, A. hydrophila, V. harveyi, and V. parahaemolyticus). The results indicated the highest inhibitory effect of 20 mM CdO NPs across all concentrations (30, 60, and 90 μg/mL), demonstrating significant inhibition against S. marcescens. These findings will contribute to the development of novel strategies for combating aquatic diseases and advancing aquaculture health management practices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Mosquitoes stand out as the most perilous and impactful vectors on a global scale, transmitting a multitude of infectious diseases to both humans and other animals. The primary objective of the current research was to assess the effectiveness of EOs from Ocimum tenuiflorum L. and Ocimum americanum L. in controlling Anopheles stephensi Liston. Culex quinquefasciatus Say and Aedes aegypti L. mosquitoes. The larvae, pupae and eggs of the mosquitoes were exposed to four different concentrations (6.25-50 ppm). The tested EOs resulted in >99-100 % mortality at 120 h for the eggs of all examined mosquito species. It also showed robust larvicidal and pupicidal activity with LC 50 and LC 90 values of 17-39, 23-60 ppm and 46-220, and 73-412 ppm against Aedes, Culex and Anopheles mosquito species, respectively, at 24 h of treatment. The Suitability Index or Predator Safety Factor demonstrated that the EOs extracted from O. tenuiflorum L. and O. americanum L. did not cause harm to P. reticulata, D. indicus (water bug), G. affinis and nymph (dragonfly). GC-MS analysis identified the major probable constituents of the oil, including Phenol, 2-Methoxy-4-(1-Propenyl)- (28.29 %); 1-Methyl-3-(1'-Methylcyclopropyl) Cyclopentene (46.46 %); (E,E,E)-3,7,11,15-Tetramethylhexadeca-1,3,6,10,14-Pentaene (18.91 %) and 1,3-Isobenzofurandione, 3a,4,7,7a-Tetrahydro-4,7-Dimethyl (33.02 %). These constituents may play a significant role in the mosquitocidal activity of the oil. The same results were identified in the formulation prepared from the EOs. This marks the first report confirming the successful utilization of EOs derived from O. tenuiflorum L. and O. americanum L. in mosquito population control initiatives., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Two-step water electrolysis has been proposed to tackle the ticklish H 2 /O 2 mixture problems in conventional alkaline water electrolysis recently. However, low buffering capacity of pure nickel hydroxide electrode as redox mediator limited practical application of two-step water electrolysis system. A high-capacity redox mediator (RM) is urgently needed to permit consecutive operation of two-step cycles and high-efficiency hydrogen evolution. Consequently, a high mass-loading cobalt-doped nickel hydroxide/active carbon cloth (NiCo-LDH/ACC) RM is synthesized via a facile electrochemical method. The proper Co doping can apparently enhance the conductivity and simultaneously remain the high-capacity of the electrode. Density functional theory results further confirms more negative values in redox potential of NiCo-LDH/ACC than Ni(OH) 2 /ACC on account of the charge redistribution induced by Co doping, which can prevent the parasitic O 2 evolution on RM electrode during decoupled H 2 evolution step. As a result, the NiCo-LDH/ACC combined the superiorities of high-capacity Ni(OH) 2 /ACC and high-conductivity Co(OH) 2 /ACC, and the NiCo-LDH/ACC with 4:1 ratio of Ni to Co presented a large specific capacitance of 33.52F/cm 2 for reversible charge-discharge and high buffering capacity with two-step H 2 /O 2 evolution duration of 1740 s at 10 mA/cm 2 . The necessary input voltage (2.00 V) of the whole water electrolysis was broken into two smaller ones, 1.41 and 0.38 V, for H 2 and O 2 production, respectively. NiCo-LDH/ACC provided a favorable electrode material for the practical application of two-step water electrolysis system., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Two-step alkaline water electrolysis is considered a safe and efficient method for producing hydrogen from renewable energy. Reversal of the current polarity in a bifunctional electrocatalyst used as a gas evolution electrode (GEE) in two-step water electrolysis can generate H 2 /O 2 at different times and in different spaces. The design of a bifunctional electrocatalyst with high durability and excellent activity is imperative to achieving continuous, safe, and pure H 2 generation via two-step alkaline water electrolysis. Here, we present for the first time a novel 3D Mo-doped NiCo phosphide honeycomb electrocatalyst that was grown on nickel foam (3D Mo-NiCoP/NF) and fabricated using polystyrene as a template. The electrocatalyst exhibited extremely low overpotentials in both the hydrogen evolution reaction (HER; 117 mV at 10 mA/cm 2 ) and the oxygen evolution reaction (OER; 344 mV at 100 mA/cm 2 ). As a bifunctional electrocatalyst for two-step alkaline water electrolysis, the device had a 1.784 V cell voltage at 10 mA/cm 2 , 95% decoupling efficiency, and ∼83% energy conversion efficiency. Taken together, the use of 3D Mo-NiCoP/NF as a GEE reduced the complexity and lowered the cost of the electrolyzer. The latter could be used to construct highly competitive water-splitting systems for continuous H 2 production and green energy harvesting., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Nanoscale zero-valent iron (nZVI or Fe 0 ) can rapidly reduce Cr(VI) contaminants in the water environment, but the agglomeration and passivation of the Fe 0 system have adverse effects on its application. In this study, a novel mesoporous Santa Barbara Amorphous-15 supported Fe/Ni bimetallic composite (SBA-15@Fe/Ni) is proposed to remove Cr(VI). The proposed material can enhance the stability and removal capacity of the nZVI system. The results show that the unique six-way through-hole structure of SBA-15 provides a place for the dispersion of Fe 0 particles. Meanwhile, SBA-15 effectively alleviates the accumulation of Fe 0 particles. The removal efficiency of SBA-15@Fe/Ni is better than two single systems (SBA-15 and Fe/Ni). The removal efficiency of SBA-15@Fe/Ni towards Cr(VI) can reach 97.62% after 60 min at pH 4.0. SBA-15@Fe/Ni still maintains excellent performance in the presence of various competitive ions (Cl - , SO 4 2- , CO 3 2- , NO 3 - ). At 298 K, the maximum removal capacity of SBA-15@Fe/Ni towards Cr(VI) is 180.99 mg/g. The possible removal process of SBA-15@Fe/Ni towards Cr(VI) is divided into the following steps: First, Cr(VI) is attracted into the vicinity of the SBA-15@Fe/Ni channel by the electrostatic attraction; Second, the reduction of Cr(VI) occurs after contacting with the Fe/Ni system, and its driving force mainly comes from nZVI and Fe(II); Furthermore, the introduction of Ni can promote Cr(VI) reduction through electron transfer and catalytic hydrogenation. In conclusion, adopting SBA-15@Fe/Ni to treat chromium contamination is an effective and promising approach., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Pseudomonas aeruginosa (PA) is an opportunistic pathogen that causes high mortality in cystic fibrosis patients. Treatment failures often occur due to the emergence of antibiotic resistance. Inhibition of virulence factors production without suppressing the growth of the pathogens is a potential alternative strategy to control the antibiotic resistance. In order to accomplish, three different interaction studies were performed using Bacillus subtilis BR4, PA and their extracellular contents. Firstly, co-cultivation was performed with different cell density of BR4 or PA. In co-culture setup (F), high cell density of BR4 significantly inhibits the biofilm formation of PA in a growth-independent manner (p < 0.01). To substantiate the biofilm inhibition, LC-MS/MS was performed and metabolic profile of monocultures and cocultures were compared. Multivariate analysis corroborated that metabolic profile of coculture setup (F) is drastically different from other coculture and monoculture setups. To check the effect of extracellular content of PA on BR4, supernatant of PA was extracted with ethyl acetate and different concentration of that extract (PA-EXT) was supplemented with BR4 culture. Exogenous supplementation PA-EXT (40 μg/mL) led to increased biofilm inhibitory activity (p < 0.01) in BR4. Further, to check the effect of extracellular content of BR4, PA was grown in the supernatant of BR4. PA survives in the spent media of BR4 without biofilm formation. Though 50% spent media of BR4 was replaced with fresh media, PA could not produce biofilm. In support of this, LC-MS/MS analysis has revealed that abundance of quorum sensing (QS) signals was reduced in the spent media grown PA than control. Furthermore, BR4 protects zebrafish larvae (Danio rerio) against PA infection and increases their survival rate (p < 0.05). We found that PA-induced oxidative stress and apoptosis were also significantly reduced in the BR4-pretreated larval group than control group. These results clearly indicate that BR4 exerts growth-independent QS inhibition in PA, suggesting that it could be used as a probiotic for future therapeutic interventions., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Analyzing the health benefits of any two immunostimulants (synbiotics) in combined form and information on their interactions gain more visibility in the usage of synbiotics in aquafarms. With this intention, the current work explores the immunostimulant effect and structural interaction of synbiotic (β-1, 3 glucan binding protein from marine crab, Portunus pelagicus (Ppβ-GBP) and Bacillus licheniformis) on Oreochromis mossambicus. The experimental diet was prepared with Ppβ-GBP and B. licheniformis, and nourished to the fingerlings of O. mossambicus for 30 days. After the experimental trial, a higher growth rate and immune reactions (lysozyme, protease, myeloperoxidase and alkaline phosphatase activity) were noticed in the fish nourished with synbiotic (B. licheniformis and Ppβ-GBP) enriched diet. Moreover, the synbiotic enriched diet elevated the antioxidant responses like glutathione peroxidase (GSH-Px) and catalase (CAT) activity in the experimental diet-nurtured fish. At the end of the feed trial, synbiotic diet nourished fish shows an increased survival rate during Aeromonas hydrophila infection, reflecting the disease resistance potential of experimental fish. Also, the interaction between Ppβ-GBP and Bacillus licheniformis was analyzed through computational approaches. The results evidenced that, Ppβ-GBP interacts with the B. licheniformis through sugar-based ligand, β-glucan through a hydrogen bond with a good docking score. Thus, the synbiotic diet would be an effective immunostimulant to strengthen the fish immune system for better productivity., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Magnetic carbon materials promise distinct advantages in the decontamination of heavy metal ions. In this work, a novel interconnected hierarchical nickel-carbon (Ni@IHC) hybrid was synthesized by combining the solvothermal method with a one-step pyrolysis under argon atmosphere. Benefitting from 3D flower-like morphology, interconnected porous nanosheets, large surface area, and abundant Ni nanoparticles, Ni@IHC hybrids can remove Cr(VI) within 25 min by using formic acid (FA) as a reductant at 25 ℃. Furthermore, the experimental parameters that can affect the material catalytic performance such as initial Cr(VI) concentration, catalyst dosage, FA concentration, and temperature were also investigated in detail. It was found that highly dispersed Ni nanoparticles contributed significantly to the reduction process. More importantly, the embedded Ni nanoparticles favor fast separation by a magnet and were helpful for the recycles use. This Ni@IHC hybrid was obtained by a facile and easy scale-up method, resulting in the fast transformation of Cr(VI) into Cr(III)., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Here we attempted to synthesize β-1,3-glucan binding protein-based silver nanoparticles (Phβ-GBP-AgNPs) and evaluate its wound healing and disease resistance prompting ability in Oreochromis mossambicus. Using a column chromatography technique, an immune molecule, Phβ-GBP was purified from the haemolymph of rice field crab, Paratelphusa hydrodromus. Phβ-GBP-AgNPs were synthesized and described through SDS-PAGE, UV-vis spectroscopy, HR-TEM, XRD and FTIR analysis. HR-TEM revealed that the synthesized Phβ-GBP-AgNPs were spherical with a 20-40 nm size range and the particles were not aggregated. Wound and infection were experimentally generated in O. mossambicus and treated with Phβ-GBP, chem-AgNPs and Phβ-GBP-AgNPs for 20 days. The immune parameters (peroxidase, lysozyme and protease) and antioxidant enzymes (SOD and catalase) were examined in the serum of experimental fish. Phβ-GBP-AgNPs elevated the immune and antioxidant enzymes during the healing process and enhanced the wound healing percentage in fish than Phβ-GBP and chem-AgNPs. The immune parameters and antioxidant enzymes were declined in the serum of fish (treated with Phβ-GBP-AgNPs) after the mid-period of wound healing. Compared to others, relative percentage survival was increased in experimentally wounded and infected fish treated with Phβ-GBP-AgNPs against Aeromonas hydrophila. Moreover, Phβ-GBP-AgNPs exhibited less toxicity towards Artemia salina than chem-AgNPs during 24 h exposure period. As a result, Phβ-GBP-AgNPs may act as an alternative to commercial antibiotics and be considered an effective immunostimulant in treating skin lesions in intensive farming., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Mushrooms have an important role in sustainability since they have long been used as valuable food source and traditional medicine around the world. Regrettably, they are among the most rigorously affected populations, along with several plants and animals, due to the destructive activities of mankind. Thus the authentication and conservation of mushroom species are constantly needed to exploit the remarkable potential in them. In this perspective, an attempt has been made to identify and assess the biological attributes of psychedelic mushrooms collected from Kodaikanal, Tamil Nadu, India. The macromorphological features of the psychedelic mushroom DPT1 helped its presumptive identification and the molecular characters depicted by DNA marker revealed its close relationship with the genus Psilocybe. Accordingly, the psychedelic mushroom was identified as Psilocybe cubensis DPT1 and its crude ethyl acetate extract on analysis revealed the occurrence of phytoconstituents like alkaloids, flavonoids, tannins, saponins and carbohydrates. Moreover, it exhibited 80% larvicidal activity against Culex quinquefasciatus mosquito at 800 ppm concentration and an array of antibacterial effects with utmost susceptibility of Proteus vulgaris, and the identification of bioactive compounds by different analytical techniques substantiate that the bioactivities might be due to the presence of phytochemicals. The results of the study indicated that the extract of P. cubensis DPT1 having notable antibacterial and mosquito larvicidal efficacies which could be probed further for the isolation of medicinally important as well as bio-control compounds., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

β-Glucan-binding protein (βGBP) is important for the rational expansion of molecular biology. Here, zinc oxide nanoparticle (ZnONP) was synthesized using βGBP from the crab Scylla serrata (Ss-βGBP-ZnONP). Ss-βGBP-ZnONP was observed as a 100 kDa band on sodium dodecyl sulfate polyacrylamide gel and characterized with UV-vis spectroscopy at 350 nm. X-ray diffraction analysis displayed values consistent with those for zincite. Fourier transform infrared spectroscopy revealed the presence of functional groups, including amide, alcohol, alkane, alkyl halide, and alkene groups. The zeta potential (-5.36 mV) of these particles indicated their stability, and transmission electron microscopy revealed the presence of 50 nm nanocones. Ss-βGBP-ZnONPs were tested at 100 μg/mL against the gram-positive Enterococcus faecalis and gram-negative Pseudomanas aeruginosa using confocal laser scanning microscopy and the bacterial viability assay was also performed. The growth of MCF7 breast cancer cells was inhibited following treatment with 75 μg/mL Ss-βGBP-ZnONPs. Thus, Ss-βGBP-ZnONPs have the ability to control the growth of pathogenic bacteria and inhibit the viability of MCF7 breast cancer cell lines., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Eleusine coracana (Finger millet) has high nutritional value with numerous health benefits and is of low cost. Isolation of beta-glucan (βG) from E. coracana (Ec-βG) has gained increasing research attention. UV-vis spectroscopy used to measure the surface plasmon resonance at 361 nm to confirm the presence of polysaccharides (glucan molecules) in Ec-βG. X-ray diffraction analysis of Ec-βG displayed a crystalline nature and confirmed the presence of the βG molecule. Further, the bioactive compounds of Ec-βG were screened using gas chromatography-mass spectrometry. The antibacterial activity of Ec-βG against both Gram-positive (Lysinibacillus fusiformis, Enterococcus faecalis) and Gram-negative (Proteus vulgaris, Shigella sonnei) bacteria were assessed through minimum inhibitory concentrations <70 μg/ml of Ec-βG. In addition, the antibiofilm activity and bacterial viability of Ec-βG at 100 μg/ml was confirmed by light and confocal laser scanning microscopy. Furthermore, Ec-βG inhibits α-amylase and α-glucosidase at an IC 50 -value of 1.23 and 1.42 μg/ml, respectively. Superoxide anion scavenging activity at IC 50 -1.4 μg/ml and DPPH radical scavenging activity at IC 50- 1.2 μg/ml showed that Ec-βG had potential antioxidant property. The in vitro hemolysis assay for biocompatibility of Ec-βG at 200 μg/ml showed 0.06 ± 0.09%. Therefore, Ec-βG has the potential to act as a suggestive agent for antibacterial, antidiabetic, and antioxidant activity., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Ammonia is a widespread pollutant that is toxic to living organisms in aquaculture. This study aimed to evaluate the effects of a diet supplemented with beta-glucan from yeast, Saccharomyces cerevisiae (Sc-βG), on the stress response of Oreochromis mossambicus (Tilapia) to ammonia. Fish were divided into four groups, including a control fed a basal diet and three experimental groups fed diets supplemented with Sc-βG at 2, 5 and 10 mg/g respectively. After 8 weeks, experimental groups were exposed to ammonia at 100 mg L -1 for 1 week. Growth was measured after the 8-week feeding trial and serum, mucus, and liver tissue were sampled before and after the ammonia challenge. Compared with the control diet, feed supplemented with Sc-βG at 10 mg/g significantly (p < 0.05) improved growth performance (7.8-9.9 g increase in weight). The cellular immune responses (myeloperoxidase, reactive oxygen species, and reactive nitrogen species), humoral immune responses (alkaline phosphatase, lysozyme, and peroxidase inhibition), and antioxidant response (catalase, superoxide dismutase, and glutathione) were tested in serum, mucus and liver tissue. Compared with the control, these responses were significantly (p < 0.05) enhanced at 10 mg/g supplementation with Sc-βG. This study demonstrates that Sc-βG may be applied to induce stress tolerance and improve growth performance in aquaculture., Competing Interests: Declaration of competing interest The authors state that there is no conflict of interest., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Soil contamination has enlarged over the decades due to intensive use of pesticides and chemical fertilizers in agronomy. Earthworms are significant organisms in the soil community. Earthworms are the major role in soil fertility in most ecological system and the production of biogenic structures. Moreover, earthworm gut mucus enhances the beneficial soil microorganism potential biological activities. They are used as model organisms for assessing the ecological risks of chemicals. Enrichment of essential nutrients in soil through earthworm is a cost-effective and eco-friendly approach. In India, the organophosphorus pesticide monocrotophos is commonly used to control agricultural pests. Hence, it is important to study the effect of monocrotophos on the gut microbiota in Lampito mauritii. A 15-day exposure to a low (1/10th of the LC 50 after 96 h i.e., 0.093 ppm kg -1 ) and high sublethal concentration (1/3rd of the LC 50 after 96 h i.e., 0.311 ppm kg -1 ) of monocrotophos led to reduced proliferation of the gut microbiota in L. mauritii. However, exposure for 30 days led to a recuperation of the microbial populations to near control values. Among the eight bacterial and five fungal species that inhabit the gut of L. mauritii, only six bacterial and three fungal species were able to survive after exposure to monocrotophos. In addition to the study, histopathological changes were observed in the intestine of L.mauritii after application of lower sublethal concentration of monocrotophos. Severe pathological changes such as vacuolization, degenerated nuclei, damaged villi and congestion of the blood sinuses were noticed in the intestine on 1st and, 5th day of the experiment. But in 30th day the damages were slowly recovered due to degradation of monocrotophos by the presence of some pesticides degrading bacterial and fungal species and regenerative capability of chloragogen cells in the intestine. The results suggested that reduced microbial populations and pathological damages in intestine were observed during the application of monocrotophos. So, the monocrotophos have several harmful impacts on earthworms., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

β-cyclodextrin decorated graphene oxides (β-CD-GO) was prepared by using an in-situ aggregation treatment, and used to remove inorganic (Pb(II)) and organic pollutants (1-naphthol) from water environment. The batch adsorption experiments of as-prepared β-CD-GO were carried out as a function of pH values, initial Pb(II) and 1-naphthol concentration, ionic strength, contact time and temperature. β-CD-GO kinetic results indicated that the adsorption was dominated by chemisorptions and followed a pseudo-second order model. The maximum adsorption capacities of β-CD-GO toward Pb(II) and 1-naphtholon the base of the Langmuir model were 149.56 and 207.6 mg·g -1 at 293 K, respectively. The thermodynamic experiments revealed that the adsorption of Pb(II) and 1-naphthol was spontaneous and endothermic. The surface compexation, hydrogen bonds and π-π interactions contributed to Pb(II) and 1-naphthol adsorption by means of the hydroxy and carboxyl functional groups on the surface of the β-CD-GO. The experimental results indicate that the β-CD-GO is an excellent composite for the elimination of Pb(II) and 1-naphthol from wastewater., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Biofilm forming pathogenic bacteria showing resistance towards antimicrobial agents has increased the urge to find an alternative treatment strategy. Among the biofilm forming pathogenic bacteria, Pseudomonas aeruginosa is a well-recognised Gram negative biofilm former causing nosocomial infection and other disease among immunocompromised patients. The aim of the current study is to evaluate the antipathogenic potentials of S. platensis against P. aeruginosa. S. platensis methanolic extract (SME) inhibited the biofilm (89%), extracellular polymeric substances (EPS), cell surface hydrophobicity (CSH) (44%), pyocyanin, pyoveridin and swarming motility of P. aeruginosa. Partial purification of SME using thin layer chromatography (TLC), column chromatography and gas chromatography mass spectroscopy (GCMS) revealed the major component as hexadecanoic acid (HxD). Further analysis through in silico approach showed the efficient binding of HxD with the biofilm regulatory proteins (Las R and salidase enzyme) of P. aeruginosa. The coating of HxD over different material surfaces efficiently prevented the adhesion of P. aeruginosa biofilm. The results of the toxicity assay revealed that the SME is non-toxic towards Artemia salina at the given concentration. Hence the overall work proves the potential non-toxic effects of SME against P. aeruginosa pathogenicity., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Chitosan is the second most abundant polymer obtained from the byproduct of seafood. Chitosan and its derivatives and chitosan loaded drugs are the recent area of interest against microbial pathogenesis. The cationic chitosan nanoparticles (ChNPs) interact with the anionic surfaces of the microbial cell membrane, which promotes antimicrobial activity. Although, ChNPs are potential against pathogenic microbes, selection of adaptable, suitable and cost effective synthesis method is much important. In the present study, ChNPs were synthesized adopting ionic gelation using sodium tripolyphosphate as a cross linking agent and characterized by FTIR, DLS, SEM and TEM analysis. ChNPs were investigated for antimicrobial activity against bacterial (Escherichia coli and Staphylococcus aureus) and fungal (Candida albicans) pathogens. ChNPs showed bactericidal activity at the lower minimum inhibitory concentration of about 40-80 μg mL -1 . Interestingly, ChNPs exhibits biocompatible antioxidant property by inhibiting DPPH free radicals at 76% and also proven to be a potential candidate against the microbial pathogenesis with an inevitable applications in biomedicine., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Pseudomonas aeruginosa is a Gram negative, opportunistic biofilm forming pathogenic bacterium which is developing as a serious problem worldwide. The pathogenicity of P. aeruginosa mainly depends upon biofilm and quorum sensing (QS) mechanism. Targeting biofilm and QS regulated factor will automatically reduce the pathogenicity of P. aeruginosa. Therefore it is compulsory to identify naturally derived biofilm and QS inhibitors against P. aeruginosa. In the present study Oscillatoria subuliformis, a marine cyanobacterium was used against the biofilm and QS of P. aeruginosa. O. subuliformis intracellular methanolic extract (OME) at different concentration (1.5 μg mL -1 , 3 μg mL -1 and 5 μg mL -1 ) was tested against several virulence factors like Extracellular Polymeric Substance (EPS), Cell Surface Hydrophobicity (CSH), elastase, pyocyanin and swarming motility. OME inhibited biofilm (56%), EPS (40%), CSH (56%), pyocyanin (27%), elastase activity and swarming motility in P. aeruginosa without interfering in their survival. Characterization of the OME using FTIR and GCMS confirmed palmitic acid and oleic acid as active compound. CLSM analysis of catheter coated with OME, palmitic and oleic acid proved biofilm inhibition over urinary catheters. The results postulates that oleic and palmitic acid could be an effective attenuator of P. aeruginosa pathogenesis., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The successful treatment of multi-drug resistant microbial pathogens represents a major challenge for public health management. Here, chitosan-alginate (CS/ALG) microspheres with narrow size distribution were fabricated by ionically cross linking method using Ca 2+ ions as agents for polymer solidification. The physicochemical properties of CS/ALG microspheres, such as surface morphology and size, were studied by SEM. The functional group interactions were confirmed by Fourier transform infrared (FTIR) spectroscopy. SEM revealed that the CS/ALG microspheres were spherical in shape with smooth surfaces, size was 50-100 μm. The synthesized CS/ALG microspheres showed antibacterial and antibiofilm activity on bacteria of public health relevance. CS/ALG microspheres exhibited antibacterial activity at the concentration of 5-20 μg, with significant inhibitory zones on multiple antibiotic resistant pathogens, including Gram positive Staphylococcus aureus, Enterococcus faecalis, and Gram negative Pseudomonas aeruginosa and Proteus vulgaris. Furthermore, in situ light microscopy and confocal laser scanning microscopy (CLSM) showed that CS/ALG microspheres inhibited the bacterial biofilm formation in S. aureus, E. faecalis P. aeruginosa and P. vulgaris after a single treatment with 40 μg. Overall, our findings underlined that chemically synthesized CS/ALG biomaterial has high antibacterial and antibiofilm activity against a number of microbial pathogens of interest for human health, thus this synthesis route can be further exploited for drug development in current biomedical science., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The green fabrication of metal nanoparticles using botanical extracts is gaining increasing research attention in nanotechnology, since it does not require high energy inputs or the production of highly toxic chemical byproducts. Here, silver (Ag), gold (Au) and their bimetallic (Ag/Au) nanoparticles (NPs) were green synthesized using the Gloriosa superba aqueous leaf extract. Metal NPs were studied by spectroscopic (UV-visible spectroscopy, fluorescence spectroscopy, FT-IR spectroscopy, XRD and EDX) and microscopic (AFM and TEM) analysis. AFM and TEM showed that Ag and Au NPs had triangular and spherical morphologies, with an average size of 20 nm. Bimetallic Ag/Au NPs showed spherical shapes with an average size of 10 nm. Ag and Ag/Au bimetallic NPs showed high antibacterial and antibiofilm activities towards Gram-positive and Gram-negative bacteria. Overall, the proposed synthesis route of Ag, Au and Ag/Au bimetallic NPs can be exploited by the pharmaceutical industry to develop drugs effective in the fight against microbic infections., (Copyright © 2016 Elsevier Ltd. All rights reserved.)