17 research outputs found

    Robust superhydrophobic cellulose nanofiber aerogel for multifunctional environmental applications

    Get PDF
    The fabrication of superadsorbent for dye adsorption is a hot research area at present. However, the development of low-cost and highly efficient superadsorbents against toxic textile dyes is still a big challenge. Here, we fabricated hydrophobic cellulose nanofiber aerogels from cellulose nanofibers through an eco-friendly silanization reaction in liquid phase, which is an extremely efficient, rapid, cheap, and environmentally friendly procedure. Moreover, the demonstrated eco-friendly silanization technique is easy to commercialize at the industrial level. Most of the works that have reported on the hydrophobic cellulose nanofiber aerogels explored their use for the elimination of oil from water. The key novelty of the present work is that the demonstrated hydrophobic cellulose nanofibers aerogels could serve as superadsorbents against toxic textile dyes such as crystal violet dye from water and insulating materials for building applications. Here, we make use of the possible hydrophobic interactions between silane-modified cellulose nanofiber aerogel and crystal violet dye for the removal of the crystal violet dye from water. With a 10 mg/L of crystal violet (CV) aqueous solution, the silane-modified cellulose nanofiber aerogel showed a high adsorption capacity value of 150 mg/g of the aerogel. The reason for this adsorption value was due to the short-range hydrophobic interaction between the silane-modified cellulose nanofiber aerogel and the hydrophobic domains in crystal violet dye molecules. Additionally, the fabricated silane-modified cellulose nanofiber hydrophobic aerogels exhibited a lower thermal conductivity value of 0.037 W\ub7m -1 K -1 , which was comparable to and lower than the commercial insulators such as mineral wools (0.040 W\ub7m -1 K -1 ) and polystyrene foams (0.035 W\ub7m -1 K -1 ). We firmly believe that the demonstrated silane-modified cellulose nanofiber aerogel could yield an eco-friendly adsorbent that is agreeable to adsorbing toxic crystal violet dyes from water as well as active building thermal insulators

    Evaluation of the neuroprotective activity of P. amarus in attenuating arsenic-induced neurotoxicity - an in vivo study

    No full text
    Background: Arsenic is viewed as a bizarre and frightful element in human history. Recent studies showed that even low levels of arsenic can cause neurological damage. Phyllanthus amarus is an important medicinal herb proved to have neuro protective effect in experimental animals. This pre-clinical study used an animal model of arsenic toxicity and screened the different neuroprotective mechanisms of Phyllanthus amarus ethanolic extract. Purpose: To assess the effect of Phyllanthus amarus ethanolic extract on various biochemical parameter's in the brain of arsenic administered Wistar albino rats. Methodology: The neuroprotective activity of P. amarus against arsenic induced toxicity was studied in Wistar albino rats. The experimental animals (n=24) were divided into four groups of 6 rats each. Rats in group I received distilled water, whereas rats in groups II, III, and IV received arsenic as sodium arsenite salt (40 mg/kg b.w) in drinking water daily for 28 days. In addition, rats from groups III, and IV also received P. amarus ethanolic extract 100 and 200 mg/kg b.w, by intragastric route, once daily for a period of 28 days. At the end of the experiment rats were subjected to various neurobehavioral tests such as Elevated plus maze, Light dark arena, Forced swim test and Tail suspension test. After 24 h of the last treatment, the animals were euthanized and brain tissue was assayed for various biochemical parameters. Results: ANOVA and Post hoc testing of behavioral and biochemical data (Dunnett's t-test and Student unpaired T test) showed co-administration of P. amarus ethanolic extract significantly reversed anxiety and depression-like behaviors in experimental animals. P. amarus ethanolic extract effectively reduced acetyl cholinesterase activity in the brain, and it also increased the levels of dopamine and serotonin in the brains of arsenic-treated animals as compared to only arsenic treated group. P. amarus ethanolic extract significantly decreased lipid peroxidase and increased brain catalase and super oxidase dismutase activities. Conclusion: Based on the pharmacological, and biochemical analysis the plant extracts of P. amarus have shown protective effects against arsenic induced neurotoxicity

    Trimethoxy Crown Chalcones as Multifunctional Class of Monoamine Oxidase Enzyme Inhibitors

    No full text
    Background: Chalcones with methoxy substituent are considered as a promising framework for the inhibition of monoamine oxidase (MAO) enzymes. Methods: A series of nine trimethoxy substituted chalcones (TMa-TMi) was synthesized and evaluated as a multifunctional class of MAO inhibitors. All the synthesized compounds were investigated for their in vitro MAO inhibition, kinetics, reversibility, blood-brain barrier (BBB) permeation, and cytotoxicity and antioxidant potentials. Results: In the present study, compound (2E)-3-(4-nitrophenyl)-1-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (TMf) was provided with a MAO-A inhibition constant value equal to 3.47±0.09 μM with a selectivity of 0.008, thus comparable to that of moclobemide, a well known potent hMAO-A inhibitor (SI=0.010). Compound (2E)-3-(4-bromophenyl)-1-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (TMh) show good MAO-B inhibition with inhibition constant of 0.46±0.009 μM. The PAMPA assay demonstrated that all the synthesized derivatives can cross the BBB successfully. The cytotoxicity studies revealed that TMf and TMh have 88.22 and 80.18 % cell viability at 25 μM. Compound TMf appeared as the most promising antioxidant molecule with IC50 values, relative to DPPH and H2O2 radical activities equal to 6.02±0.17 and 7.25±0.07 μM. To shed light on the molecular interactions of TMf and TMh towards MAO-A and MAO-B, molecular docking simulations and MM/GBSA calculations have been carried out. Conclusion: The lead molecules TMf and TMh with multi-functional nature can be further employed for the treatment of various neurodegenerative disorders and depressive states

    Outcomes of Birdshot Chorioretinopathy Treated With an Intravitreal Sustained-Release Fluocinolone Acetonide–Containing Device

    No full text
    To evaluate outcomes in birdshot chorioretinopathy following intravitreal implantation of a fluocinolone acetonide–containing drug delivery device. Retrospective, multicenter, interventional case study. University- and community-based tertiary care. Twenty-two HLA-A29+ birdshot patients (36 eyes) were implanted with a sustained-release corticosteroid device and followed for up to 3 years. Main outcome measures were Snellen acuity, intraocular inflammation, adjunctive therapy, cataract, ocular hypertension, or glaucoma. Paired Wilcoxon statistics were used to analyze visual acuities; paired McNemar statistics were used to analyze presence or absence of other outcomes. Nineteen of 22 patients (32 eyes) completed 12 months of follow-up with improvement in median visual acuity ( P = .015 ). Prior to implantation, 18 of 22 patients (82%) received immunosuppressive therapy versus 1 of 19 (5%) by 12 months ( P < .001). Eyes with zero vitreous haze increased from 7 of 27 scored eyes (26%) at baseline to 30 of 30 eyes (100%) by 12 months ( P < .001). Cystoid macular edema decreased from 13 of 36 eyes (36%) at baseline to 2 of 32 eyes (6%) at 12 months ( P = .006). Five of 24 phakic eyes at baseline exited the study before surgery; all other eyes received cataract surgery. One hundred percent of study eyes had ocular hypertension, required intraocular pressure–lowering therapy, or had glaucoma surgery by 12 months. Implantation of a fluocinolone acetonide–containing intraocular device in birdshot chorioretinopathy can improve vision, control inflammation, and eliminate systemic therapy. There is a high incidence of cataract progression and intraocular hypertension or glaucoma

    Effects of Withania somnifera and Tinospora cordifolia Extracts on the Side Population Phenotype of Human Epithelial Cancer Cells: Toward Targeting Multidrug Resistance in Cancer

    No full text
    Recent reports suggest the existence of a subpopulation of stem-like cancer cells, termed as cancer stem cells (CSCs), which bear functional and phenotypic resemblance with the adult, tissue-resident stem cells. Side population (SP) assay based on differential efflux of Hoechst 33342 has been effectively used for the isolation of CSCs. The drug resistance properties of SP cells are typically due to the increased expression of ABC transporters leading to drug efflux. Conventionally used chemotherapeutic drugs may often leads to an enrichment of SP, revealing their inability to target the drug-resistant SP and CSCs. Thus, identification of agents that can reduce the SP phenotype is currently in vogue in cancer therapeutics. Withania somnifera (WS) and Tinospora cordifolia (TC) have been used in Ayurveda for treating various diseases, including cancer. In the current study, we have investigated the effects of ethanolic (ET) extracts of WS and TC on the cancer SP phenotype. Interestingly, we found significant decrease in SP on treatment with TC-ET, but not with WS-ET. The SP-inhibitory TC-ET was further fractionated into petroleum ether (TC-PET), dichloromethane (TC-DCM), and n-butyl alcohol (TC-nBT) fractions using bioactivity-guided fractionation. Our data revealed that TC-PET and TC-DCM, but not TC-nBT, significantly inhibited SP in a dose-dependent manner. Furthermore, flow cytometry-based functional assays revealed that TC-PET and TC-DCM significantly inhibited ABC-B1 and ABC-G2 transporters and sensitized cancer cells toward chemotherapeutic drug-mediated cytotoxicity. Thus, the TC-PET and TC-DCM may harbor phytochemicals with the potential to reverse the drug-resistant phenotype, thus improving the efficacy of cancer chemotherapy

    A New Potent and Selective Monoamine Oxidase-B Inhibitor with Extended Conjugation in a Chalcone Framework: 1-[4-(Morpholin-4-yl)phenyl]-5-phenylpenta-2,4-dien-1-one

    No full text
    The general blueprint for the design of monoamine oxidase-B (MAO-B) inhibitors has been based on two phenyl or heteronuclei linked via a spacer of appropriate length. In this study, 1-[4-(morpholin-4-yl)phenyl]-5-phenylpenta-2,4-dien-1-one (MO10) was prepared by the condensation of 4′-morpholinoacetophenone and cinnamaldehyde in basic alcoholic medium. MO10 was assessed for inhibitory activity against two human MAO isoforms, MAO-A and MAO-B. Interestingly, MO10 showed a remarkable inhibition against MAO-B with an IC50 value of 0.044 μM along with a selectivity index of 366.13. The IC50 value was better than that of lazabemide (IC50 value of 0.063 μM), which was used as a reference. Kinetics studies revealed that MO10 acted as a competitive inhibitor of MAO-B, with a Ki value of 0.0080 μM. The observation of recovery of MAO-B inhibition, compared to reference levels showed MO10 to be a reversible inhibitor. MTT assays showed that MO10 was nontoxic to normal VERO cells with an IC50 value of 195.44 μg/mL. SwissADME predicted that MO10 provided advantageous pharmacokinetics profiles for developing agents acting on the central nervous system, that is, high passive human gastrointestinal absorption and blood–brain barrier permeability. Molecular docking simulations showed that MO10 properly entered the aromatic cage formed by Y435, Y398, and FAD of the active site of MAO-B. On the basis of these results, MO10 can be considered a promising starting compound in development of agents for the treatment of various neurodegenerative disorders

    Extraction of Cellulose Nanofibers via Eco-friendly Supercritical Carbon Dioxide Treatment Followed by Mild Acid Hydrolysis and the Fabrication of Cellulose Nanopapers

    No full text
    The conventional isolation of cellulose nanofibers (CNFs) process involves high energy input which leads to compromising the pulp fiber&rsquo;s physical and chemical properties, in addition to the issue of elemental chlorine-based bleaching, which is associated with serious environmental issues. This study investigates the characteristic functional properties of CNFs extracted via total chlorine-free (TCF) bleached kenaf fiber followed by an eco-friendly supercritical carbon dioxide (SC-CO2) treatment process. The Fourier transmission infra-red FTIR spectra result gave remarkable effective delignification of the kenaf fiber as the treatment progressed. TEM images showed that the extracted CNFs have a diameter in the range of 10&ndash;15 nm and length of up to several micrometers, and thereby proved that the supercritical carbon dioxide pretreatment followed by mild acid hydrolysis is an efficient technique to extract CNFs from the plant biomass. XRD analysis revealed that crystallinity of the fiber was enhanced after each treatment and the obtained crystallinity index of the raw fiber, alkali treated fiber, bleached fiber, and cellulose nanofiber were 33.2%, 54.6%, 88.4%, and 92.8% respectively. SEM images showed that amorphous portions like hemicellulose and lignin were removed completely after the alkali and bleaching treatment, respectively. Moreover, we fabricated a series of cellulose nanopapers using the extracted CNFs suspension via a simple vacuum filtration technique. The fabricated cellulose nanopaper exhibited a good tensile strength of 75.7 MPa at 2.45% strain

    Extraction of cellulose nanofibers via eco-friendly supercritical carbon dioxide treatment followed by mild acid hydrolysis and the fabrication of cellulose nanopapers

    No full text
    The conventional isolation of cellulose nanofibers (CNFs) process involves high energy input which leads to compromising the pulp fiber’s physical and chemical properties, in addition to the issue of elemental chlorine-based bleaching, which is associated with serious environmental issues. This study investigates the characteristic functional properties of CNFs extracted via total chlorine-free (TCF) bleached kenaf fiber followed by an eco-friendly supercritical carbon dioxide (SC-CO2) treatment process. The Fourier transmission infra-red FTIR spectra result gave remarkable effective delignification of the kenaf fiber as the treatment progressed. TEM images showed that the extracted CNFs have a diameter in the range of 10–15 nm and length of up to several micrometers, and thereby proved that the supercritical carbon dioxide pretreatment followed by mild acid hydrolysis is an efficient technique to extract CNFs from the plant biomass. XRD analysis revealed that crystallinity of the fiber was enhanced after each treatment and the obtained crystallinity index of the raw fiber, alkali treated fiber, bleached fiber, and cellulose nanofiber were 33.2%, 54.6%, 88.4%, and 92.8% respectively. SEM images showed that amorphous portions like hemicellulose and lignin were removed completely after the alkali and bleaching treatment, respectively. Moreover, we fabricated a series of cellulose nanopapers using the extracted CNFs suspension via a simple vacuum filtration technique. The fabricated cellulose nanopaper exhibited a good tensile strength of 75.7 MPa at 2.45% strain
    corecore