Browse Items (16481 total)
Sort by:
-
Biodiversity and Indigenous Medicinal Knowledge of North-East India: Navigating Climate Change Impacts on Medicinal Plants for Conservation and Advancement
The northeastern region of India holds the sixth position among the world's 25 biodiversity hotspots, covering approximately 8% of the nation's total land area, which amounts to 262, 060 square kilometres. Situated in the eastern Himalayas, any alterations in this biodiversity-rich area can have significant and far-reaching consequences. Indigenous tribes of this region believe in the remarkable healing properties of certain medicinal plants, and within its diverse population of around 225 communities, each tribal and sub -tribal group possesses distinct traditional knowledge. Capturing and harnessing this indigenous wisdom by scientists and researchers could unlock new avenues for progress, particularly within the pharmaceutical sector. Climate change stands as one of the paramount global environmental challenges. Predictions indicate that by the close of the 21st century, the Earth's average temperature might rise by anywhere between 0.3 to 4.8 C, accompanied by a potential sea level increase of 26 to 82 cm. These climate shifts could have adverse effects on the abundance and accessibility of medicinal plants, potentially leading to species extinction. Moreover, the impact of climate change could extend beyond availability to also encompass alterations in the pharmacological properties of various plants, particularly those found in alpine environments. This discussion underscores the importance of existing knowledge, critical analyses, challenges, opportunities, and the immense value of medicinal plants. It emphasizes the intersection of changing climate and the vulnerability of medicinal plant resources, necessitating a comprehensive understanding of these effects in the context of the North Eastern region of India. To address these challenges, there is a pressing need for in-depth research on the geographical distribution of plant communities and strategies to enhance the secondary synthesis of critically endangered medicinal plants under the current climate change scenarios. The Author(s). -
Biodegradation studies of polyhydroxyalkanoates extracted from bacillus subtilis NCDC 0671 /
Research Journal of Chemistry And Environment, Vol.23, Issue 6, pp.107-114 -
Biodegradation studies of polyhydroxyalkanoates extracted from Bacillus subtilis NCDC 0671
The major characteristic feature that distinguishes polyhydroxyalkanoates (PHAs) from its synthetic counterparts is its biodegradability. PHAs are the only class of biopolymers reported to be 100% degradable under both aerobic and anaerobic conditions without production of any toxic residues. The biodegradability of PHAs is influenced by several factors like moisture, temperature, pH, surface area and molecular weight of the polymer. The rate of biodegradation varies greatly depending on the environment. Biodegradation studies were carried out using plating method and direct inoculation method using selected Bacillus strains. Fungal degradation of PHA sheets was assessed using Penicillium chrysogenum. Biodegradation of PHA sheets in different soil types like river valley, agricultural land and garden soil was investigated. The degree of PHA degradation in aqueous environment was studied by incubating the sheets in distilled water, sea water, fish tank water and pond water. The highest degradation rate was observed with agriculture land soil (35.47 0.13%) and fish tank soil (36.93 0.13%). The non-toxic nature of the soil incubated with PHA sheets was ensured using plant growth test. 2019, World Research Association. All rights reserved. -
Biodegradation of polypropylene films by Bacillus paralicheniformis and Lysinibacillus fusiformis isolated from municipality solid waste contaminated soil
The fossil fuel or petroleum derived plastics are applied in our routine life because of their easy availability. Distribution and contamination of the plastics in the landfills are the major reasons for these biodegradation study. This current study reveals the biodegradation of polypropylene films and the growth of Bacillus paralicheniformis and Lysinibacillus fusiformis isolated from plastic contaminated soil collected from municipality solid waste management site. The degradation rate of PP films was confirmed by the results of biodegradation analysis. The growth of Bacillus paralicheniformis and Lysinibacillus fusiformis had shown OD values at 600nm after the degradation period of 4 weeks increasing from 0.131 to 0.334 and 0.148 to 0.213 respectively. The viable cell count increased from 804cells/ml to 1204cells/ml and 10.104cells/ml to 15.204cells/ml respectively. The physical and chemical changes of PP films were confirmed by FT-IR and XRD analysis. These analysis confirmed that the bacterial strains have the ability to change the chemical and physical nature of PP films and can utilize the PP films as sole carbon source. 2021 World Research Association. All rights reserved. -
Biodegradable Organic Polymers for Environmental Protection and Remediation
As the era of urbanization and industrialization progressed, non-biodegradable polymers became a severe threat to the environment and the world's rapidly growing population. These synthetic polymers possess flexible applications and cost effectiveness which makes their usage more feasible and convenient. Today they are used from simple packaging to critical biomedical tools. Although these polymers possess many merits, all come to halt when it comes to biodegradability. The inherent mechanisms in nature are unable to degrade and decompose these synthetic polymers leading to their accumulation and persistence in nature for decades causing calamitous effects. In search of solutions for the adverse effects caused by synthetic polymers, the world turned toward biologically synthesized biodegradable organic polymers. These biopolymers have a diverse set of physical and chemical characteristics that can be easily manipulated, allowing for a wide range of applications. Biopolymers like polyhydroxyalkanoates and levan have adaptable qualities that resemble those of synthetic plastics which makes them a promising alternative to synthetic plastics. However, the setback in the large-scale usage of biopolymers is their high cost of production and commercialization. The biopolymers are broadly classified into three major classes based on their origin: plant-based biopolymers (cellulose, starch), animal-based biopolymers (chitin, chitosan, keratin), and microbial biopolymers (polyhydroxyalkanoates, levan). The extraction or synthesis of these biopolymers from their biological sources varies significantly from each other; however, in order to bring out the sustainable production, these polymers should be produced by coupling with waste valorization approaches. The waste materials from plants and animals, particularly agro-industrial wastes, can be used as inexpensive substrates for the commercial manufacture of these crucial biopolymers, thereby reducing the accumulation in the environment. Another field of biopolymer usage is in remediation of pollutants. Many biopolymers are currently being used in the active removal of heavy metal, dye, and other similar pollutants. The numerous physical, chemical, and biological processes for extraction or synthesis of industrially valuable biopolymers from the waste raw materials are discussed in this chapter, along with their application in remediation of pollutants and environmental protection. 2025 WILEY-VCH GmbH, Boschstra 12, 69469 Weinheim, Germany. All rights reserved. -
Biodegradable blend film derived from polycaprolactone an guar gum blend for packaging application /
Patent Number: 202141012114, Applicant: Sudhakar Y N. -
Biodegradable blend film derived from polycaprolactone an guar gum blend for packaging application /
Patent Number: 202141012114, Applicant: Sudhakar Y N. -
Bioconversion of Feather Composts using Proteolytic Bacillus mycoides for their Possible Application as Biofertilizer in Agriculture
Proteolytic Bacillus strains were screened for highest protease production amongst which Bacillus mycoides (G2) was chosen as an assuring protease producer. Enzyme activity was maximum at 37C, pH-7, when the medium was supplemented with 0.5 and 0.75% of sucrose and beef extract respectively. Tapioca flour and soybean meal were capable of replacing commercial carbon and nitrogen sources respectively. Feather degradation studies revealed 62% of degradation with Quail feather (QF), followed by Chicken feather (CF) (58%), Guinea fowl feather (51%) and Pigeon feather (43%). Biodegradation of feather samples in soil evidenced degradation of Quail feather and Chicken feather at the following patternQF Treatment 1 (5%) ? CF Treatment 1 (5%) ? QF Treatment 2 (10%) ? CF Treatment 2 (10%). Maximum degradation of QF and sufficient release of free amino acids into the feather compost was obvious with Field Emission Scanning Electron Microscopic (FE-SEM) and High Performance Thin Layer Chromatographic (HPTLC) analyses respectively. In vitro plant growth studies of tomato and chilly plants were accomplished with feather composts. Maximum growth of 26.44cm (shoot length) was achieved when feather compost prepared with degraded QF (5%) was utilized as plant growth substrate, than other treatment pots (P < 0.05). Plant growth was exemplary in the case of tomato when compared to that of chilly. Sound degradation of QF, followed by CF using Bacillus mycoides could strengthen the efficacy of microbial fermentation processes. This significant attempt could support poultry farms as well as organic agricultural sectors ecologically. Graphic Abstract: [Figure not available: see fulltext.] 2021, The Author(s), under exclusive licence to Springer Nature B.V. -
Bioconversion of chicken feather waste into feather hydrolysate by multifaceted keratinolytic Bacillus tropicus LS27 and new insights into its antioxidant and plant growth-promoting properties
Abstract: Keratin, the main structural constituent of feathers, contains a lot of valuable amino acids which are potential bioactive compounds as well. Since conventional methods are not efficient enough to achieve complete removal of chicken feather waste, biological mode of feather degradation is one of the most appropriate ways to utilize feathers, thereby reducing wastes as well as generating value-added products from feathers. This study was focussed on valorizing chicken feather into feather hydrolysate (FH) containing bioactive compounds for plant growth promotion. Keratinolytic bacteria capable of degrading chicken feathers were isolated from the poultry waste dumping site of Russell Market, Shivajinagar, Bangalore, Karnataka, India. The isolated bacteria was identified as Bacillus tropicus LS 27. A minimal media with chicken feather as the sole source of carbon and nitrogen was prepared and inoculated with Bacillus tropicus LS 27 [5% (v/v)]. Degradation of keratin protein by bacteria caused the solubilization of amino acids which was confirmed by high-performance liquid chromatography (HPLC) analysis where an appreciable amount of amino acids like cysteine, valine, isoleucine, proline, lysine, methionine, and phenylalanine was detected. The Fourier transform infrared spectroscopy (FTIR) analysis of hydrolysed chicken feathers showed C=0 stretching, S-H bond stretching, and formation of carboxylic acid groups indicating effective degradation of chicken feathers. Scanning electron microscope (SEM) images revealed the degradation pattern of feathers showing complete degradation of barbs and barbules with a portion of rachis remaining. Feather hydrolysate was further explored for its antioxidant activity using DPPH scavenging assay, and the value was found to be 1.5 mg/mL. The bacterial cells when screened for heavy metal tolerance showed significant metal tolerance to lead (Pb) and chromium (Cr). Since Bacillus tropicus LS27 showed indole-3-acetic acid (IAA), siderophore, and ammonia production, the prepared feather hydrolysate along with the bacterial cells were used as soil amendment for plant growth studies over Spinacia oleracea L. The study revealed that plants supplemented with 20% (v/v) FH showed elevated plant growth, therefore proving to be optimum for the support of plant growth. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023. -
Bioconversion of chicken feather waste into feather hydrolysate by multifaceted keratinolytic Bacillus tropicus LS27 and new insights into its antioxidant and plant growth-promoting properties
Abstract: Keratin, the main structural constituent of feathers, contains a lot of valuable amino acids which are potential bioactive compounds as well. Since conventional methods are not efficient enough to achieve complete removal of chicken feather waste, biological mode of feather degradation is one of the most appropriate ways to utilize feathers, thereby reducing wastes as well as generating value-added products from feathers. This study was focussed on valorizing chicken feather into feather hydrolysate (FH) containing bioactive compounds for plant growth promotion. Keratinolytic bacteria capable of degrading chicken feathers were isolated from the poultry waste dumping site of Russell Market, Shivajinagar, Bangalore, Karnataka, India. The isolated bacteria was identified as Bacillus tropicus LS 27. A minimal media with chicken feather as the sole source of carbon and nitrogen was prepared and inoculated with Bacillus tropicus LS 27 [5% (v/v)]. Degradation of keratin protein by bacteria caused the solubilization of amino acids which was confirmed by high-performance liquid chromatography (HPLC) analysis where an appreciable amount of amino acids like cysteine, valine, isoleucine, proline, lysine, methionine, and phenylalanine was detected. The Fourier transform infrared spectroscopy (FTIR) analysis of hydrolysed chicken feathers showed C=0 stretching, S-H bond stretching, and formation of carboxylic acid groups indicating effective degradation of chicken feathers. Scanning electron microscope (SEM) images revealed the degradation pattern of feathers showing complete degradation of barbs and barbules with a portion of rachis remaining. Feather hydrolysate was further explored for its antioxidant activity using DPPH scavenging assay, and the value was found to be 1.5 mg/mL. The bacterial cells when screened for heavy metal tolerance showed significant metal tolerance to lead (Pb) and chromium (Cr). Since Bacillus tropicus LS27 showed indole-3-acetic acid (IAA), siderophore, and ammonia production, the prepared feather hydrolysate along with the bacterial cells were used as soil amendment for plant growth studies over Spinacia oleracea L. The study revealed that plants supplemented with 20% (v/v) FH showed elevated plant growth, therefore proving to be optimum for the support of plant growth. Graphical abstract: [Figure not available: see fulltext.] 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. -
Bioconvective flow of nanofluid past a cylinder subject to ThompsonTroian slip
The bioconvective flow of a nanofluid across a cylinder under the impact of ThompsonTroian slip conditions is studied in this work. The nonzero velocity at the boundary, which affects the distribution of shear stress and, in turn, the overall flow pattern, is explained by this slip condition. Additionally, the paper covers the dynamics of nanofluid flow and its mass and heat transfer characteristics. Partial differential equations (PDEs) that characterize the momentum, energy, concentration and species movement in the fluid, are used to simulate the flow. Through similarity transformations, these PDEs are transformed into a system of ordinary differential equations (ODEs), simplifying the intricate flow phenomena. After applying the similarity transformations, the resulting system of ODEs is solved via the RungeKuttaFehlberg (RKF45) technique. The study emphasizes how important precise modeling and numerical solutions are for managing and predicting bioconvective flows in real-world applications, including cooling systems, chemical reactors and microfluidic devices. The results provide a basis for further research into more complex flow scenarios as well as for the creation of cutting-edge materials and technologies that take advantage of nanofluid dynamics. The changes in the slip parameter resulted in 12.23% changes in the Nusselt number, whereas the changes in the magnetic field parameter accounted for 1.22.4%. However, the velocity of the nanofluid was found to decrease for a stronger magnetic field. 2025 World Scientific Publishing Company. -
Bioconvective flow of bi-viscous Bingham nanofluid subjected to Thompson and Troian slip conditions
This paper describes the bioconvection phenomenon and its significant influence on the thermal features of the flow of bi-viscous Bingham (BVB) nanofluid past a vertically stretching flat surface. The analysis of the impact of convection parameters is considered along with various other forces. Meanwhile, the flow of BVB nanofluid is put through the slip conditions defined by Thompson and Troian for the velocity at the boundary. The flow of BVB nanofluid is modeled using the partial differential equations (PDEs) under the assumptions of thermophoresis and Brownian motion which occur due to the movement of nanoparticles. Along with these forces, the radiation is also considered so that the obtained results are close to the practical scenarios. Thus, using the proper Lie group similarity transformations, the intended mathematical model is converted into ordinary differential equations (ODEs). The resulting equation system is encoded using the RKF-45 technique, and the outcomes are explained using graphs and tables. The solutions found for the model showed that, for higher ranges of the non-Newtonian fluid parameter, the velocity decreases while the heat transferred by the nanofluid increases. The availability of motile density at the surface grows as the Plet number rises, whereas the Schmidt numbers decline in their respective profiles. 2023 World Scientific Publishing Company. -
Bioconvective DarcyFrochherimer flow of the ReeEyring nanofluid through a stretching sheet with velocity and thermal slips
In the current study, the bioconvective flow of ReeEyring through an expanding sheet with the porous medium is analyzed by considering the inclined magnetic field and gyrotactic microorganisms. Buongiorno's model, which defines the two major mechanisms; thermophoresis and Brownian motion is used to frame the mathematical model. The presence of motile cells helps in stabilizing the nanoparticle and avoids the sedimentation due to nanoparticles. The mathematical model with these assumptions is framed using partial differential equations (PDE) that are later remodeled to ordinary nonlinear differential equations by incorporating desirable similarity transformation. The equations so obtained shall be solved using DTM and the outcomes are described through graphs and tables. The graphs indicated that the velocity of the nanofluid flow reduces with the increase in the porosity and similarly, the higher values of Peclet number (Pe) are found to diminish the motile density. Whereas the increase in the thermophoresis parameter enhances the thermal and mass profiles of the nanofluid. 2022 Informa UK Limited, trading as Taylor & Francis Group. -
Bioconvection of a radiating hybrid nanofluid past a thin needle in the presence of heterogeneous-homogeneous chemical reaction
The photocatalytic nature of TiO2 finds applications in medicinal field to kill cancer cells, bacteria, and viruses under mild ultraviolet illumination and the antibacterial characteristic of Ag makes the composition Ag - TiO2 applicable for various purposes. It can also be used in other engineering appliances and industries such as humidity sensor, coolants, and in footwear industry. Hence, this study deals with the analysis of the effects of magnetic field, thermal radiation, and quartic autocatalysis of heterogeneous-homogeneous reaction in an electrically conducting Ag - TiO2 - H2O hybrid nanofluid. Furthermore, the gyrotactic microorganisms are used as active mixers to prevent agglomeration and sedimentation of TiO2 that occurs due to its hydrophobic nature. The mathematical model takes the form of partial differential equations with viscosity and thermal conductivity being the functions of volume fraction. These equations are converted to ordinary differential equations by using similarity transformation and are solved by RKF-45 method with the aid of shooting method. It is observed that the increase in the size of the needle enhances the overall performance of the hybrid nanofluid. Furthermore, the temperature of the hybrid nanofluid increases with the increase in volume fraction. It is observed that the friction produced by the Lorentz force increases the temperature of the nanofluid. It is further observed that the heterogeneous reaction parameter has more significant effect on the concentration of bulk fluid than the homogeneous reaction parameter. Copyright 2021 by ASME. -
Bioconvection in buoyancy induced flow of Williamson nanofluid over a Riga Plate-DTM-Padapproach
The buoyancy induced flow of Williamson nanofluid containing Gyrotactic microorganisms along a vertical Riga plate has been investigated. This research aims at analysing the heat and mass transfer characteristics of Williamson Nanofluid in the presence of Gyrotactic microorganisms that helps in avoiding the agglomeration of nanoparticles during the nanofluid flow. The Gyrotactic microorganisms act as active mixers that help in stabilising the nanoparticles in the suspension. Also, the movement of these cells gives rise to a macro phenomenon called bioconvection that helps in preventing the agglomeration of nanoparticles. Furthermore, the magnetic field generated due to the flow of nanofluid is considered in addition to Thermophoresis and Brownian Motion to make the results more appropriate. Buongiornos Model has been incorporated to frame the system of equations that govern the fluid flow. Later, lie group analysis is performed to transform these equations into ordinary differential equations that are further solved using the differential transform method with Padapproximant. It is observed that the Lorentz force generated by the Riga plate in parallel to the flow helps in increasing the velocity of the nanofluid. It is also noticed that bioconvection reduces the flow speed and enhances the heat transfer rate. 2020 by American Scientific Publishers All rights reserved. -
Biocontrol potential of Flemingia wightiana: A natural weapon against Culex quinquefasciatus
Globally, mosquito-borne diseases, particlulalry those transmitted by Culex quincquefasciatus pose a significant public health challenge. Traditional methods of eradication using synthetic insecticides pose environmental concerns and a risk of developing insecticide-resistant varieties. Here, the use of plant-based biopesticides offers a safer and sustainable alternative. The study aimed to investigate the insecticidal properties of Flemingia wightiana (FW) leaves by synthesising leaf extracts and silver nano-particles. The toxicity of the test samples was tested on Oreochromis niloticus at concentrations of 0.1, 0.5, and 1 mg/L. Furthermore, the test samples were subjected to lethality assay on C. quinquefasciatus. Laboratory bioassays were conducted to evaluate the efficacy of crude extract and silver nanoparticles of F. wightiana at varying concentrations, specifically 0.5, 1, 2, and 4 mg/L. Ovicidal, emergency and larvicidal activity were studied. The results indicated significant larvicidal activity and exhibited better potential for toxicity against Culex larvae treated with AgNPs. FW-AgNPs have substantial effect in delaying the hatching of mosquito eggs. Moulting of larvae from one instar to the next was also delayed by treatment with AgNPs. The findings demonstrated that FW-AgNPs play a significant role in controlling C. quinquefasciatus populations. : Author (s). Publishing rights and ANSF. -
Biocontrol of Aedes aegypti using Talaromyces islandicus Synthesized Silver Nanoparticles
Aedes aegypti is the vector that spreads the dengue virus, causing dengue fever and dengue hemorrhagic fever. With more than half the worlds population at the risk of acquiring this infection, controlling the Aedes mosquitoes is the only path to limit the spread of the fatal disease. The emergence of insect resistance in mosquitoes raised the need for developing novel insecticides. Present research is focused on using fungus (Talaromyces islandicus) as the biosystem in the synthesis of nanoparticles. Myco-synthesized silver nanoparticles were characterized using UV-visible spectrometry that exhibited a peak at 429 nm. The XRD spectral peaks were in the range of 27.83, 32.27, 38.23and 65.01. The FTIR spectrum showed peaks corresponding to O-H, N-O, S=O, etc. representing the silver nanoparticles. SEM and EDAX represent the formation of silver ions that are spherical in shape with a size range of 23 to 26 nm. The antioxidant activity of silver nanoparticles and the extract of Talaromyces islandicus were assessed by DPPH assay, reducing power assay and hydrogen peroxide assay. The nanoparticles studied for its bio efficacy against the larval stages of Aedes aegypti indicated the LC50 value of 352.03, 389.86, 397.72 and 443.50 when tested against first, second, third and fourth instar larvae. respectively. The LC50 value of 540.41 was determined against the pupae of Aedes. The predatory efficiency of P. reticulata indicated the positive feeding behaviour of the fish when exposed to the silver nanoparticles. The cell toxicity assay was conducted against C6/36 insect cell lines and the cell viability inhibition was calculated. A toxic free, environmentally acceptable approach for controlling the mosquito vector by utilizing fungal nanoparticles was assessed and their efficacy in vector control was analyzed in this study. 2022 Chemical Publishing Co.. All rights reserved. -
Biocompatible Sodium Alginate Modified BaO2H2O2 Nanoparticles With Improved Therapeutic Efficacy Against Multidrug-Resistant Pathogens and Cancer Cells
The increasing problem of multidrug-resistant pathogens and the limitations of conventional therapies for cancer treatments require designing new therapeutic agents. BaO2H2O2 and BaSA nanoparticles were prepared and characterized to determine their antimicrobial, antifungal, and anticancer activities. The XRD confirmed the crystallite sizes to be 34 nm for BaO2H2O2 and 25 nm for BaSA. The UVvisible analysis confirmed the band gap energies as 4.13 and 4.11 eV for BaO2H2O2 and BaSA, respectively. A shift in the blue-green PL emission from 488510 nm in BaO2H2O2 to 535 nm in BaSA indicated increased oxygen vacancies. EDAX analysis demonstrated elemental variations due to SA modification, whereas DLS measurements showed a decrease in the mean size of the nanoparticles from 116.70 nm (BaO2H2O2) to 111.90 nm (BaSA). Antimicrobial activity was shown against Klebsiella pneumoniae, Shigella dysenteriae, Escherichia coli, Pseudomonas aeruginosa, and Proteus vulgaris, while a considerable enhancement of antifungal activity against Candida albicans was observed in BaSA. Against MG-63 osteosarcoma cells, BaSA exhibited lower IC50 values (21.5, 20.2, 18.7 ?g mL?1 at 24, 48, and 72 h) when compared with BaO2H2O2 (23.4, 22.5, 21.3 ?g mL?1). Zebrafish embryos tolerated BaSA at 0.5 mg mL?1, with developmental abnormalities observed only at 1.0 mg mL?1. 2025 John Wiley & Sons Ltd. -
Biocompatible Pluronic F127-coated nickel titanate nanoparticles: toward effective antimicrobial and antioxidant therapies
Multidrug-resistant bacterial infections are a major global health concern. Nickel titanate (NiTiO?) nanoparticles offer potential antimicrobial applications, but their biocompatibility is limited. This study explores the surface modification of NiTiO? with Pluronic F127 (PF127) to enhance biological performance. NiTiO? nanoparticles were synthesized and coated with PF127. Characterization was performed using XRD, FTIR, HRTEM, BET and DLS. Antibacterial activity was assessed via pathogenic bacteria assays and colony-forming unit quantification. Antioxidant activity was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and zebrafish embryos evaluated in vivo toxicity. XRD confirmed hexagonal NiTiO?, and FTIR/HRTEM verified PF127 incorporation. BET analysis indicated a surface area of 28.66 m2 g?1 and mesoporous structure (2.59 nm pore diameter). DLS showed particle size reduction from 219.3 nm (NiTiO?) to 135.9 nm (NiTiO?PF127), confirming improved dispersion. NiTiO?PF127 exhibited enhanced antibacterial activity, with colony-forming unit counts decreasing in a concentration-dependent manner. The DPPH assay showed 53.7% radical scavenging at 20 ?g mL?1. Zebrafish embryo studies revealed higher viability and lower developmental toxicity for PF127-coated nanoparticles compared to uncoated NiTiO?. PF127 modification of NiTiO? improves dispersion, antibacterial and antioxidant activity, and biocompatibility. These results highlight NiTiO?PF127 nanocomposite as a promising candidate for biomedical and antimicrobial applications. 2026 Society of Chemical Industry. 2026 Society of Chemical Industry. -
Biocompatible NiTiO3Dopamine nanocomposites for combating drug-resistant pathogens through membrane disruption and oxidative stress
The rising threat of multidrug-resistant pathogens poses a challenge to public health. Highlighting the urgent need for novel antimicrobial agents, this study reports the synthesis of NiTiO3 nanoparticles and dopamine-functionalized NiTiO3 nanocomposites. Structural and elemental confirmation was obtained through XPS studies, which confirmed the presence of Ni2+ and Ti4+ in the nanocomposite, along with C 1s and O 1s peaks corresponding to dopamine coating. Photoluminescence spectra revealed that the NiTiO3dopamine nanocomposite exhibits notable green emission bands at 510, 518, and 527nm which arises from deep-level recombination associated with complex oxygen-related defects like oxygen vacancies. The NiTiO3-dopamine exhibited enhanced antimicrobial activity against S. aureus, B. subtilis, K. pneumoniae, S. dysenteriae, and C. albicans, compared to NiTiO3 alone. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays further revealed that NiTiO3dopamine achieved MIC at 600?g/mL and MBC at 1000?g/mL for K. pneumoniae, outperforming pure NiTiO3. ROS assays confirmed oxidative stress-mediated antimicrobial action, with ROS levels significantly quenched in the presence of histidine. SEM images of bacterial morphology showed extensive membrane disruption in NiTiO3dopamine treated cells. Furthermore, zebrafish embryo assays confirmed excellent biocompatibility of the NiTiO3dopamine nanocomposite, with normal development observed up to 72h post fertilization. 2025 Published by Elsevier B.V.