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The existence of harmonics in the power distribution system (PDS) is treated as the most serious issue that affects its stability and reliability. The active power filter (APF) therefore plays a vital role in PDS to compensate for the harmonics for the improvement of the power quality (PQ) and to keep the total harmonic distortion (THD) below 5% as per IEEE-519. In this work, a three-phase four-wire (3P-4W) multi-level inverter (MLI)-based APF is proposed to overcome the shoot-through effect (STE) and reduce the distortions in the supply current. The control of the voltage source inverter (VSI) is achieved using an Adaline-based LMS (A-LMS) algorithm with a hysteresis current controller. The proposed filter that uses the A-LMS technique is compared with the conventional recursive least square (RLS) algorithm. The A-LMS approach is mainly operated for maintaining the dc link voltage of MLI, which follows the principle of capacitor energy and reduces the total harmonic distortion (THD) under different load variations. The performance of MLI under different load conditions is designed, developed, and validated by using a MATLAB/Simulink environment, and the preeminent features are established.

Abstract Background The transcription factor NFκB is an important mediator of cell survival and inflammation in the immune system. In the central nervous system (CNS), NFκB signaling has been implicated in regulating neuronal survival following acute pathologic damage such as traumatic brain injury (TBI) and stroke. NFκB is normally bound by the principal inhibitory protein, IκBα, and sequestered in the cytoplasm. Activation of NFκB requires the degradation of IκBα, thereby freeing NFκB to translocate to the nucleus and activate the target genes. Mice deficient in IκBα display deregulated and sustained NFκB activation and early postnatal lethality, highlighting a critical role of IκBα in NFκB regulation. Results We investigated the role of IκBα in regulating NFκB activity in the brain and the effects of the NFκB/IκBα pathway in mediating neuroinflammation under both physiological and brain injury conditions. We report that astrocytes, but not neurons, exhibit prominent NFκB activity, and that basal NFκB activity in astrocytes is elevated in the absence of IκBα. By generating mice with brain-specific deletion of IκBα, we show that IκBα deficiency does not compromise normal brain development. However, basal neuroinflammation detected by GFAP and Iba1 immunoreactivity is elevated. This leads to impaired inflammatory responses following TBI and worsened brain damage including higher blood brain barrier permeability, increased injury volumes and enlarged ventricle volumes. Conclusions We conclude that, in the CNS, astrocyte is the primary cell type subject to NFκB regulation. We further demonstrate that IκBα plays an important role in regulating NFκB activity in the brain and a robust NFκB/IκBα-mediated neuroinflammatory response immediately following TBI is beneficial.

Currently, Nano-materials have been explored for their abundant biomedical applications. In the present study the green synthesized (SC-AgNPs) by root extract of Smilax Chenensis have been characterized by UV-visible spectroscopy revealed SPR peak at 432 nm and FT-IR data reveals that the bioactive components of root extract have been actively involved in the reduction and stabilization of SC-AgNPs. TEM and AFM results revealed that SC-AgNPs were roughly spherical in shape. Further, the particle size of SC-AgNPs was also carried out by Dynamic Light Scattering method by aqueous colloidal solution and the results reveals that the SC-AgNPs are poly-dispersed in nature with an average size 45.6 nm with a Z average of 39.5 nm. The stability of colloidal SC-AgNPs was further confirmed by negative zeta potential value of - 21.0 mV. The SC-AgNPs showed good antibacterial activity against both gram -ve and gram + ve bacteria, whereas, SC-AgNPs coupled with antibiotic reveals excellent and enhanced antibacterial activity. The gram -ve E.coli and gram + ve S.aureus revealed highest zone of inhibition when compared to other two bacterial species. So, SC-AgNPs coupled with antibiotics can be excellent alternative to treat antibiotic resistant bacteria. The SC-AgNPs also reveals excellent antioxidant activity among them DPPH method revealed superior activity with an IC 50 value76.22. The SC-AgNPs also reveals superior anticancer activity against MDA-MB-231 with IC 50 value of 33.98 µg/mL and photo-catalytic activity the optical density of reduced from 1.861 to 0.135 OD within 30 min. The green SC-AgNPs detected to have multiple therapeutic applications., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

The present research was carried out to look into therapeutic insight of biosynthesized silver nanoparticles (AgNPs) by leaf extract of Byttneria herbacea Roxb (BH). The analysis of biosynthesized BH-AgNPs by UV-visible spectroscopy shows an intense surface plasmon resonance (SPR) peak at 422 nm initially and 437 nm after 30 min which certainly reveals the formation of BH-AgNPs. Fourier Infra-red Spectroscopy (FT-IR) reveals that BH-AgNPs are biosynthesized by using different bioactive compounds like O-H stretch of free hydroxyl alcohol and phenols, N-H bond of primary amines present in the leaf extract. Transmission Electron Microscope (TEM) analysis revealed that BH-AgNPs are almost spherical in nature with an average size range from of 2 nm to 12 nm. The particle size analysis by Dynamic Light Scattering (DLS) reveals that the BH-AgNPs are poly-dispersed in nature with an average size of 8 nm ± 2 nm, with a negative zeta potential value of -21 mV which reveals the biosynthesized BH-AgNPs are very stable. The BH-AgNPs ( Byttneria herbacea -AgNPs ) revealed excellent free radical scavenging activity and exceptional antimicrobial activity. The anti-proliferative and cytotoxic studies in KB oral cancer cells revealed biosynthesized BH-AgNPs can employ as future novel therapeutic agents in cancer treatment and other biomedical applications.

This study focuses on a one-pot solvothermal synthetic route for the preparation of uniformly decorated zinc oxide nanoparticles on the surface of reduced graphene oxide (rGO/ZnO-NC) by using Andrographis paniculata leaf aqueous extract as an eco-friendly reducing agent. After characterizing the samples by different physical and chemical techniques, the anticancer activity of the synthesized rGO/ZnO-NC was examined on two human cancerous cell lines (HCT116 and A549) and one normal cell line (hMSCs). The MTT assays revealed that rGO/ZnO-NC exhibited dose-dependent cytotoxicity at a maximum concentration range of 10 ppm and the viability of the cells was drastically decreased to 95-96%. Measurement of reactive oxygen species (ROS) generation and Annexin V-FTIC staining assay revealed that rGO/ZnO-NC induced apoptosis in HCT116 and A549 cell lines. Thus, this study shows that the green-synthesized rGO/ZnO-NC has great potential in developing an efficacious novel therapeutic agent for cancers., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

In the present investigation, green synthesis of silver nanoparticles (AgNPs) was carried out using aqueous leaf extract of Argyreia nervosa . The results of the spectral characterisation have revealed that the surface Plasmon resonance band was observed at 421 nm confirms the formation of AgNPs. The Fourier Transform Infra-red Spectroscopy result shows the reduction of silver nitrate into AgNPs by the reduction of different functional groups. Transmission Electron Microscope analysis revealed that the particles are roughly spherical and poly-disperse in shape and size, the particles are within the size range of 10-55 nm. Dynamic Light Scattering revealed that the nanoparticles were also within the range of 10-50 nm, An-AgNPs have a high negative zeta potential value of -38.9 mV. An-AgNPs showed efficient free radical scavenging activity and showed excellent antimicrobial activity. Anti-proliferative and cytotoxic effect of An-AgNPs was carried out by MTT assay against KB oral cancer cells, the IC 50 value of An-AgNPs is 58.64 µg/ml. The cell's growth is arrested at the G2/M phase, so the An-AgNPs activated the Caspase 3 pathway which leads to the Apoptosis of KB oral cancer cells. So it is concluded that the green synthesised An-AgNPs have manifold functions.

The current investigation highlights the green synthesis of silver nanoparticles (AgNPs) by the insectivorous plant Drosera spatulata Labill var. bakoensis, which is the first of its kind. The biosynthesized nanoparticles revealed a UV visible surface plasmon resonance (SPR) band at 427 nm. The natural phytoconstituents which reduce the monovalent silver were identified by FTIR. The particle size of the Ds-AgNPs was detected by the Nanoparticle size analyzer confirms that the average size of nanoparticles was around 23 ± 2 nm. Ds-AgNPs exhibit high stability because of its high negative zeta potential (- 34.1 mV). AFM studies also revealed that the Ds-AgNPs were spherical in shape and average size ranges from 10 to 20 ± 5 nm. TEM analysis also revealed that the average size of Ds-AgNPs was also around 21 ± 4 nm and the shape is roughly spherical and well dispersed. The crystal nature of Ds-AgNPs was detected as a face-centered cube by the XRD analysis. Furthermore, studies on antibacterial and antifungal activities manifested outstanding antimicrobial activities of Ds-AgNPs compared with standard antibiotic Amoxyclav. In addition, demonstration of superior free radical scavenging efficacy coupled with potential in vitro cytotoxic significance on Human colon cancer cell lines (HT-29) suggests that the Ds-AgNPs attain excellent multifunctional therapeutic applications., (© 2021. The Author(s).)

Biosynthesis of plant-mediated silver nanoparticles is gaining significant importance due to environmentally safe 'green method' and it is an efficient alternative method. In the present study, silver nanoparticles were synthesized by using root extract of Glycyrrhiza glabra an important medicinal plant. The AgNPs are characterized by spectral analysis; the surface plasmon resonance (SPR) peak of AgNPs showed maximum absorption at 445 nm. Fourier-transform infrared spectroscopy (FT-IR) data show that the O-H hydroxyl groups, carboxylic acids, ester and ether groups and C-O stretching of alcohols have been utilized in the formation of AgNPs. The X-ray powder diffraction (XRD) data reveal that the AgNPs are face-centered cubic (fcc) in structure. The size was determined by particle size analyzer and atomic force microscope (AFM); the results reveal that AgNPs were spherical in shape and the average grain size is determined as 41.5-46.5 nm. Transmission electron microscopy (TEM) micrographs obtained show that AgNPs were roughly spherical and well dispersed with the sizes ranging from 10 to 45 nm ± 5 nm. The biofabricated AgNPs are extremely stable due to its high negative zeta potential -34.1 mV which indicates that the nanoparticles are polydispered in nature. The cytotoxic studies of AgNPs on human CD34 +ve stem cells in microcarrier culture reveal excellent growth at different concentrations of biosynthesized AgNPs. This is the first report of microcarrier culture of CD34 +ve stem cells on biosynthesized AgNPs.

The enhancement of plant secondary metabolite production in cell suspension cultures through biotic or abiotic elicitation has become a potential biotechnological approach for commercialization or large-scale production of bioactive compounds. Gymnema sylvestre R.Br. is an important medicinal plant, rich in a group of oleanane triterpenoid saponins called gymnemic acid, well known for its anti-diabetic activity. Two endophytic fungal strains were isolated from the leaves of G. sylvestre and identified as Polyancora globosa and Xylaria sp. based on the PCR amplification and internal transcribed spacer (ITS 1-5.8S-ITS 2) sequencing of 18S rRNA gene. The process of elicitation of cell suspension cultures of G. sylvestre with dried powder of fungal mycelia (DPFM) and extracellular culture filtrate (ECF) of endophytic fungi consistently enhanced the accumulation of gymnemic acid and the DPFM was proved to be an effective elicitor when compared to the ECF. The DPFM elicited the gymnemic acid content in the range of 2.57-10.45-fold, while the ECF elicited the gymnemic acid content in the range of 2.39-7.8-fold. P. globosa, a novel and a rare endophytic fungal strain, has shown a great influence on the production of gymnemic acid. Cell suspension cultures elicited with DPFM of P. globosa produced higher amount of gymnemic acid content (124.23 mg/g dried cell weight) compared to the cultures elicited with DPFM of Xylaria sp. (102.24 mg/g DCW). But the cultures treated with consortium of DPFM of both fungi showed great influence on the production of gymnemic acid (139.98 mg/g DCW) than the cultures treated with DPFM alone. Similarly, cultures treated with consortium of ECF of both fungi produced more gymnemic acid content (94.86 mg/g DCW) compared with cultures treated with ECF of Xylaria sp. (77.93 mg/g DCW) and ECF of P. globosa (78.65 mg/g DCW) alone.

The present study reports that the biosynthesis of AgNPs using an endophytic fungus isolated from the ethnomedicinal plant Centella asiatica. The endophytic fungus was identified as Aspergillus versicolor ENT7 based on 18S rRNA gene sequencing (NCBI Accession number KF493864). The AgNPs synthesized were characterized by UV-visible spectroscopy, Fourier transform infra-red spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD), particle size analyzer, and zeta potential measurements. The UV-Vis absorption spectra showed the peak at 429 nm which confirmed the synthesis of AgNPs. TEM analysis revealed that the AgNPs were spherical in shape with 3-40 nm in size; similar results were also obtained by Horiba particle size analyzer with 5-40 nm in size. The synthesized AgNPs were highly stable due to their high negative zeta potential value of -38.2 mV. XRD studies showed (111), (200), (220), (311), and (222) planes of the face-centered cubic (FCC) lattice, indicating the crystalline nature of the AgNPs. Selected area electron diffraction (SAED) pattern of the AgNPs showed five circular fringes which were in accordance with XRD data and confirmed the formation of high crystalline nature of AgNPs. FTIR measurements indicated the peaks at 3273, 2925, 1629, 1320, and 1020 cm -1 corresponding to different functional groups possibly involved in the synthesis and stabilization of AgNPs. The synthesized AgNPs exhibited effective free radical scavenging activity with the IC50 value of 60.64 µg/ml. The synthesized AgNPs were found to be highly toxic against both gram-positive and gram-negative bacteria and also showed a very good antifungal activity.

New and novel strategies are of recent interest in the development of silver nanoparticles. The plant extracts are eco-friendly, economical and cost effective for synthesis of nanoparticles. In this paper, we represent biofabrication of silver nanoparticles (AgNPs) using Andrographis paniculata and the synthesized AgNPs was monitored by ultra-violet visible spectroscopy (UV-Vis). The morphology and crystalline nature of AgNPs were determined from scanning electron microscopy (SEM) with Energy dispersive X-ray (EDX), X-ray diffraction patterns (XRD), Fourier transform-infrared spectroscopy (FT-IR). The size and the stability were detected by using Nanoparticle analyzer. The average size of the AgNPs was found to be 54 ± 2 nm and the Zeta potential was found to be -50.7 mV. The synthesized AgNPs have very good antifungal activity., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Nanoparticles have been used to alter and improve the pharmacokinetic and pharmacodynamic properties of various types of drug molecules. The plant extracts are eco-friendly, economical and cost effective for synthesis of large scale of nanoparticles. In this paper we represent the synthesis of silver nanoparticles (AgNPs) from room dried leaves of Vinca rosea. The AgNPs were characterized by UV-vis spectroscopy. The AgNPs are crystalline in nature, were determined from scanning electron microscopy (SEM) coupled with energy dispersive X-ray (EDX), X-ray diffraction patterns (XRD), and also the size of the NPs was calculated by using Hariba Nanoparticle analyzer and the stability was calculated by using the Zetapotential. The nanoparticles obtained from leaf extracts were of size 27±2 and 30±2 respectively and Zetapotential of AgNPs was found to be -63.1 mV, so it indicates the dispersion and stability. The synthesized AgNPs have very good antimicrobial activity., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Iron-sulfur (Fe-S) clusters are key metal cofactors of metabolic, regulatory, and stress response proteins in most organisms. The unique properties of these clusters make them susceptible to disruption by iron starvation or oxidative stress. Both iron and sulfur can be perturbed under stress conditions, leading to Fe-S cluster defects. Bacteria and higher plants contain a specialized system for Fe-S cluster biosynthesis under stress, namely the Suf pathway. In Escherichia coli the Suf pathway consists of six proteins with functions that are only partially characterized. Here we describe how the SufS and SufE proteins interact with the SufBCD protein complex to facilitate sulfur liberation from cysteine and donation for Fe-S cluster assembly. It was previously shown that the cysteine desulfurase SufS donates sulfur to the sulfur transfer protein SufE. We have found here that SufE in turn interacts with the SufB protein for sulfur transfer to that protein. The interaction occurs only if SufC is present. Furthermore, SufB can act as a site for Fe-S cluster assembly in the Suf system. This provides the first evidence of a novel site for Fe-S cluster assembly in the SufBCD complex.