Mechanism and Isotherm Modeling of Effective Adsorption of Malachite Green as Endocrine Disruptive Dye using Acid Functionalized Maize Cob (AFMC)

Cationic Malachite green has been identified as a candidate of endocrine disruptive compound found in the environment. In this study, the mechanism and isotherm modeling of effective adsorption of cationic malachite green dye onto acid functionalized maize cob (AFMC) was investigated by batch technique. The operational parameters such as initial concentration (100 – 600 mg/L); contact time (10 – 120 mins) and pH (3 – 10) influenced the removal efficiency and quantity adsorbed. Maximum of 99.3% removal efficiency was obtained at optimum conditions. AFMC physicochemical properties (surface area 1329 m2 /g and particle size 300μm0.97 and consistently low values of SSE, X2, HYBRID and MSPD adsorption statistical error functions (ASEF), equilibrium data were best fitted to Freundlich isotherm. Kinetic data were best described by pseudo second-order model with consistent R2 >0.98 and validated by ASEF. The mechanism of process was better described by intraparticle diffusion. Evidence of adsorption process was confirmed by change in morphology and surface chemistry determined by SEM and FTIR respectively. The performance of AFMC enlisted it as a sustainable and promising low-cost adsorbent from agro-residue for treatment of endocrine disruptive dye polluted water

Preparation and Characterization of Modified Adsorbents Derived from Pawpaw (Carica papaya) Leaf

The feasibility of a new and novel adsorbent was investigated by impregnation of pawpaw leaf (Carica papaya) in H2SO4 and NaOH respectively. The adsorbents prepared were characterized using FTIR, SEM, TGA and EDX techniques respectively. Physicochemical parameters of these adsorbents such as pH, moisture content, ash content, porosity and iodine number were also carried out; the results were then compared with the expensive commercial activated carbon (CAC) parameters. A close agreement in moisture, pH, porosity, ash content and iodine number of the acid activated pawpaw leaf (Carica papaya) shows its feasibility as a good and effective adsorbent. Conclusively, the present investigation shows that acid activated C. papaya leaf is a good and viable alternative adsorbent, which could be used in lieu of expensive CAC for adsorption processes

In Vivo Antiplasmodial Potential of the Leaf, Mesocarp, and Epicarp of the Raphia hookeri Plant in Mice Infected with Plasmodium berghei NK65

Background of the study. Raphia hookeri G. Mann & H. Wendl (Arecaceae) is an important plant used in folkloric medicine to treat various ailments such as inflammation, tumor, microbial infections, paralysis, hypertension, and rheumatism, primarily in Africa and Asia. Aim and Objectives. The study was designed to investigate the antiplasmodial and antioxidant potencies of Raphia hookeri leaves, mesocarp, and epicarp using Plasmodium infected mice. The bioactive constituents were further explored via gas chromatography-mass spectrometry (GC-MS). Results. The presence of alkaloids, fats and oils, phenolic, and flavonoids was detected via the qualitative test which was confirmed from the result obtained from the GC-MS chromatogram of ethanolic leaves extract. The GC-MS chromatogram of the constituents analogous to the twenty peaks was analyzed as follows: dodecanoic acid (1.94%), 2-undecanone (3.42%), hexadecanoic acid (44.84%), oleic acid (7.45%), octadecanoic acid (8.41%), narcissidine (2.38%), 1-dotriacontanol (2.38%), α-sitosterol (2.02%), and lupeol (1.42%). The total phenolics and flavonoids of 118 and 23.3702 mg/g were analyzed in the leaves extract. The leave extract exhibited inhibitory activity of 73.49% against free radicals which could lead to inflammation. The extracts and chloroquine-treated groups showed significant decrease in percentage parasitaemia with pronounced activity observed in chloroquine groups. Conclusion. The curative and scavenging potencies of studied plant could be attributed to the metabolites analyzed and could guide the formulation of new pharmacophores against malaria infections and inflammations

Silver nanoparticle synthesis by Acalypha wilkesiana extract: phytochemical screening, characterization, influence of operational parameters, and preliminary antibacterial testing

© 2019, The Author(s). Introduction: The application of skin bleaching products to inhibit melanogenesis is a common practice within the African diaspora. Despite the adverse health effects of skin bleaching, rigorous studies investigating skin bleaching behavior among these populations in the United States are limited. In our P30 pilot study, we explored predictors of skin bleaching practice intensity among African and Afro-Caribbean women. Methods: In collaboration with our Community Engagement Core, we conducted a cross-sectional study to investigate the relationship between demographic and psychosocial predictors and skin-bleaching-related practice patterns among African and Afro-Caribbean women in New York City. Results: Among the 76 participants recruited, the median age at the initiation of skin bleaching was 19.5 (16–25) years, yielding a median duration of 13.5 (6–23) years. Although pregnant women were not actively recruited for the study, 13.2% (n = 10) of the participants used skin bleaching products while pregnant or possibly breastfeeding. Nativeness and education were associated with various components of skin bleaching practice intensity, including duration of skin bleaching, daily use of products, and bleaching of the entire body. Participants’ perceived skin-color-related quality of life was not associated with skin bleaching practice intensity. Conclusion: Skin bleaching is a habitual practice that likely requires culturally sensitive interventions to promote behavioral change. The existence of prenatal and postnatal exposure to mercury, hydroquinone, and other potentially harmful chemicals in skin bleaching products highlights an urgent need to explore the adverse effects of skin bleaching practices on birth outcomes and the growth and neurodevelopment of young babies

Phytochemical Analysis and Antioxidant Potential of Raphia Hookeri Leaf and Epicarp

The contribution of oxidative stress to the pathogenesis of several health conditions and its association with life-threatening diseases such as malaria has necessitated the search for more phytochemicals with antioxidant properties. Various parts of Raphia hookeri such as the leaves, fruit and sap have been moderately studied and applied in different areas of industry. However, the epicarp is generally discarded. The ethanolic extracts of Raphia hookeri leaf and epicarp were herein investigated for their total phenolic and flavonoid contents using spectrometric methods. 1,1-diphenyl-2-picryl hydrazyl radical (DPPH) and 2,2-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) cation assays were used to determine the antioxidant potential of the extracts. The recorded Total Phenolic Content (TPC) of both extracts are comparable while the Total Flavonoid Content of the leaf extract is higher. Consequently, the antioxidant activity of the leaf extract was higher. Although the antioxidant potential of the leaf is higher (351.170±22.950 mg/g RE), the comparable TPC and the antioxidant activity exhibited by Raphia hookeri epicarp extract projects it as a rich phytochemical bio-resourse which may have future relevance in the pharmaceutical industry

Kinetics and Equilibrium Models for Sorption of Cu(II) onto a Novel Manganese Nano-adsorbent

The studies of kinetics and equilibrium sorption of Cu(II) were undertaken using nanoscale zerovalent manganese (nZVMn) synthesized by chemical reduction in a single pot system. nZVMn was characterized using scanning electron microscopy, energy dispersive x-ray, and surface area determined by Brunauer–Emmett–Teller. The effect of pH, contact time, adsorbent dose, agitation speed, initial Cu(II) concentrations, temperature, and ionic strength on the sorption of Cu(II) onto nZVMn were investigated in a batch system. The kinetic data followed pseudo-second-order. The mechanism was governed by pore diffusion. The equilibrium sorption data were tested by Freundlich, Langmuir, Temkin, Dubinin–Kaganer–Raduskevich, and Halsey isotherm models. The Langmuir monolayer adsorption capacity (Qmax = 181.818 mg/g) is much greater compared to other nano-adsorbents used in sorption of Cu(II). The thermodynamic parameters (ΔH0, ΔS0, ΔG0) revealed a feasible, spontaneous, and endothermic adsorption process. nZVMn has a great potential for effective removal of copper (II) in aqueous solution

Emerging Water Pollutants and Wastewater Treatments

The environment is continuously threatened with various kind of pollutants, which have detrimental effects not only on human health, but also on eco-systems. In general, the water body is an easy route to wastewater disposal where many contaminants of emerging concerns, such as pharmaceuticals and personal care products etc. are present. Very recently, other classes of novel water pollutants occur which include nanoplastics and nanoparticles. Here, we discuss both classical and newly emerging water pollutants categories with their possible consequences. In addition, treatments and tackling techniques of these water pollutants are summarized. Ten different areas of concern to solve these problems and challenges of emerging water pollutants are highlighted

Combating dye pollution using cocoa pod husks: a sustainable approach

The adsorptive potential of activated carbon prepared by chemical activation of Cocoa pod husk (CPHAA) to remove Congo red (CR) dye from its aqueous solution was investigated in this study. CPHAA was characterised using Energy Dispersive X-Ray, Scanning Electron Micrograph and Fourier Transform Infrared Spectroscopy techniques. The effects of contact time, initial dye concentration, pH and solution temperature were studied. Equilibrium data were fitted to Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models. The equilibrium data were best represented by Langmuir isotherm model, with maximum monolayer adsorption capacity of 43.67 mg/g. The kinetic data were fitted to Pseudo-first-order, Pseudo-second-order, Elovich and Intraparticle diffusion models; the pseudo-second-order kinetic model provided the best correlation. Thermodynamic parameters such as standard enthalpy (ΔHo), standard entropy (ΔSo) and standard free energy (ΔGo) were evaluated. The thermodynamic study showed that the process is endothermic, spontaneous and feasible. The mean free energy of adsorption shows that the mechanism is by physisorption. CPHAA was found to be an effective adsorbent for the removal of CR dye from aqueous solution

Bottom-up approach synthesis of core-shell nanoscale zerovalent iron (CS-nZVI): Physicochemical and spectroscopic characterization with Cu(II) ions adsorption application

Single pot system in chemical reduction via bottom-up approach was used for the synthesis of core shell nanoscale zerovalent iron (CS-nZVI). CS-nZVI was characterized by a combination of physicochemical and spectroscopic techniques. Data obtained showed BET surface area 20.8643 m2/g, t-Plot micropore volume 0.001895 cm3/g, BJH volume pores 0.115083 cm3/g, average pore width 186.9268 Å, average pore diameter 240.753 Å, PZC 5.24, and pH 6.80. Surface plasmon Resonance from UV-Vis spectrophotometer was observed at 340 nm. Surface morphology from SEM and TEM revealed a spherical cluster and chain-like nanostructure of size range 15.425 nm �97.566 nm. Energy Dispersive XRF revealed an elemental abundance of 96.05% core shell indicating the dominance of nZVI. EDX showed an intense peak of nZVI at 6.2 keV. FTIR data revealed the surface functional groups of Fe–O with characteristics peaks at 686.68 cm�1, 569.02 cm�1 and 434 cm�1. In a batch technique, effective adsorption of endocrine disruptive Cu(II) ions was operational parameters dependent. Isotherm and kinetics studies were validated by statistical models. The study revealed unique characteristics of CS-nZVI and its efficacy in waste water treatment

Green synthesis of silver nanoparticles using terrestrial fern (Gleichenia Pectinata (Willd.) C. Presl.): characterization and antimicrobial studies

Novel silver nanoparticles from Gleichenia Pectinata (Willd.) C. Presl. was synthesized. A combination of spectroscopic and microscopic techniques were utilized to characterize the newly synthesized Gleichenia Pectinata Silver Nanoparticles (GPAgNPs) vis-à-vis UV-Vis Spectroscopy, Fourier Transform Infra-Red (FTIR) Spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDX) and X-Ray Diffraction (XRD) Analyses. Significant absorption was observed at 460 nm resulting from the surface Plasmon resonance (SPR). A rapid rate of synthesis was observed and the best surface plasmon resonance was obtained at 105 minutes contact time. SEM and TEM showed an spherical shape of GPAgNPs with an average size of 7.51 nm. The XRD result revealed a crystalline and polydispersed GPAgNPs. GPAgNPs were effective against four antibiotic resistant pathogens and they exhibited excellent antimicrobial activity against Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae and Candida albicans. GPAgNPs favorably competed with standard antibiotics. This therefore enlisted GPAgNPs as potential antimicrobial and therapeutic agents against multidrug resistant micro-organisms (MDRM)