Seven chalcone derivatives were synthesized by the Claisen-Schmidt condensation. The structures of the compounds were confirmed by spectral data (Ultraviolet/visible, infrared, nuclear magnetic ...resonance and mass spectroscopy). The compounds were tested for their in silico and in vitro antimicrobial and antioxidant activities. The molecular docking assessments showed that all the compounds exhibited good binding affinity with the target microorganism proteins but, compounds 6e and 6g showed better binding affinity compared with the standards. The antimicrobial test revealed that all the compounds screened were active against Staphylococcus aureus and Bacillus subtilis and had minimum inhibitory concentrations (MIC) between 0.4 and 0.6 mg/mL. Compounds 6a, 6c and 6d had moderate activities on Salmonella typhi. Compounds 6b and 6c had moderate activity on Escherichia coli. Compound 6c had moderate activity on Aspergillus niger while compounds 6a and 6e had poor activity. All the compounds except compound 6e had no inhibition against Pseudomonas aeruginosa. The in-vitro antioxidant activity was assessed using ethylenediaminetetraacetate (EDTA) as the standard. Compounds 6c, 6e and 6g gave excellent inhibitory activity better than the standard. Compound 6a gave good activity at 500 μg/mL and 1000 μg/mL concentrations but, below the standard at 250 μg/mL and no inhibition at 125 μg/mL. Compound 6d had good inhibition at 500 μg/mL and 1000 μg/mL but, no inhibition at 125 μg/mL and 250 μg/mL. Compound 6b was found to be inactive in all the concentrations. Absorption, distribution, metabolism and excretion properties of the compounds were assessed using SwissADME. The results of lead likeness showed that compound 6e is a lead-like molecule.
The Antibiogram properties of 1-chloro-2-isocyanatoethane derivatives of thiomorpholine (CTC), piperazine (CPC) and morpholine (CMC) were evaluated by the approved agar well diffusion, the minimum ...inhibitory concentration (MIC) and in silico techniques. A total of fourteen microbial cultures consisting of ten bacteria and four yeast strains were used in the biological study while affinity of the compounds for DNA gyrase, a validated antibacterial drug target, was investigated by docking method. Results indicate that both thiomorpholine and piperazine had zero activity against the Gram negative organisms tested. With morpholine, similar result was obtained except that cultures of Escherichia coli (ATCC 15442) and Salmonella typhi (ATCC 6539) presented with weak sensitivity (7-8 mm) as shown by the inhibition zone diameter (IZD) measurement. The Gram positive organisms were more sensitive to morpholine than the other compounds. The highest IZD values of 15-18 mm were achieved except for Streptococcus pneumoniae (ATCC 49619) in which mobility of the compound stopped after 12 mm. S. pneumoniae was resistant to both thiomorpholine and piperazine. The yeast strains were not sensitive to any of the studied compounds investigated. The MIC tests evaluated against a reference antibiotic show that while morpholine was most active at 4 μg.ml-1 against both B. cereus ATCC (14579) and B. subtilis, the least active compound was thiomorpholine which inhibited S. aureus (ATCC 25923) at 64 μg.ml-1. The three compounds demonstrated high affinity for the target protein (DNA gyrase) ranging from -4.63 to -5.64 Kcal/mol and even showed better ligand efficiencies than three known antibiotics; chlorobiocin, ciprofloxacin and tetracycline. This study identified the studied compounds as potential antibiotic leads with acceptable physicochemical properties and gave the molecular basis for the observed interactions between the compounds and the target protein which can be harnessed in structural optimization process.
This work evaluated the use of Dialium guineense seed waste (DGS) and its sodium hydroxide modified form (NH-DGS) as biosorbent for ciprofloxacin (CPF) from synthetic solution as well as the ...desorption potentials. Central composite design (CCD) was applied for optimization of the alkaline treated biosorbent by response surface methodology using design expert. Both biosorbents were characterized by FTIR, SEM, EDX, and BET analysis. The CCD showed NaOH concentration of 0.46 M and temperature of 96 °C to be effective for optimized modification of NH-DGS. Optimum removal of CPF was obtained at pH 6.0, contact time 120 min, temperature 300 K, and dosage of 0.1 g. The Freundlich model gave the best fit compared to the other isotherms tested with R
2
values >0.97951. NH-DGS exhibited a maximum uptake capacity of 120.34 mg/g higher than some reported adsorbents for CPF. The pseudo-second-order model was suitable in the fitting of the kinetic data. A non-spontaneous process was obtained for CPF biosorption on DGS which became spontaneous after alkaline treatment. Over 84% desorption of CPF was achieved on both biosorbents using 0.3 M HCl which envisaged the use of NH-DGS as an efficient material for treatment of waters contaminated with CPF.
The concentrations, sources, and risk of twenty organochlorine pesticides (OCPs) in soils and dusts from a typical urban setting in the Niger Delta of Nigeria were examined. The Σ20 OCP ...concentrations (ng g−1) varied from 4.49 to 150 with an average value of 32.6 for soil, 4.67 to 21.5 with an average of 11.7 for indoor dust, and 1.6 to 96.7 with an average value of 23.5 for outdoor dust. The Σ20 OCP concentrations in these media were in the order: soil > outdoor dust > indoor dust, which was in contrast with the order of the detection frequency, i.e., indoor dust (95 to 100 %) > soil (60 to 90 %) > outdoor dust (30 to 80 %). The concentrations of the different OCP classes in these media followed the order: aldrin + dieldrin + endrin and its isomers (Drins) > chlordanes > dichlorodiphenyltrichloroethane (DDTs) > hexachlorocyclohexane (HCHs) > endosulfans for outdoor dust and soil, while that of the indoor dust followed the order: Drins > chlordanes > endosulfans > DDTs > HCHs. The cancer risk values for human exposure to OCPs in these sites exceeded 10−6 which indicates possible carcinogenic risks. The sources of OCPs in these media reflected both past use and recent inputs.
Display omitted
•OCPs in dust and soils from Port Harcourt city were investigated.•OCP concentrations in soils were higher than those of outdoor and indoor dusts.•Drins and chlordanes were the dominant OCPs in these media.•Exposure to OCPs in these media pose a risk to humans.•OCPs in these media originated from predominantly aged used sources.
The concentrations of heavy metals in rice grains and soils from Ada cultivated fields were investigated. Rice and soil samples were digested and the heavy metal concentrations determined using ...atomic absorption spectrophotometer. The results showed the following concentrations of metals (mg/kg): soil-Pb (4.64 ± 2.18), Cd (0.83 ± 0.83), Zn (20.26 ± 18.60), Mn (68.90 ± 19.91), Ni (3.46 ± 2.42), and Cr (21.41 ± 14.6); rice-Pb (3.99 ± 1.43), Cd (1.10 ± 0.53), Zn (65.37 ± 58.09), Mn (37.81 ± 5.82), Ni (3.12 ± 1.49), and Cr (10.87 ± 6.47). The Canadian, Nigerian and Chinese maximum allowable concentration for cadmium in soil were exceeded by 15%, 30%, and 85% of the soil samples, respectively. Heavy metals in all the rice samples evaluated were found to be above the World Health Organization (WHO) maximum permissible limit for lead, cadmium, and chromium. Strong positive and significant correlations were observed between some metal pairs in soil and rice indicating the similarity in origin. The estimated daily intakes of Pb and Cd from rice grown on the fields were higher than the safety levels established by WHO and the Joint FAO/WHO Expert Committee Food Additive, respectively. Hazard quotients and total hazard index for Pb and Cd were greater than 1. This indicates that consumption of rice from these fields will likely induce adverse health effects arising largely from Pb and Cd exposure.
The pollution of water bodies with ciprofloxacin (CF) and other antibiotics has resulted in undesirable characteristics, such as color, odor and microbial resistance in environmental waters. Using ...agricultural waste as biosorbents for the removal of antibiotics from wastewater is a promising treatment approach. This research was based on the treatment of CF-polluted water by utilizing acid-modified
Dialium guineense
(tamarind) seed waste (HA-DGS), prepared by hydrochloric acid treatment of
Dialium guineense
seed (DGS). HA-DGS exhibited a maximum CF uptake of 125 mg/g, which was higher than most adsorbents reported in the literature. The DGS and HA-DGS were characterized by the FTIR, SEM, EDX, TGA and BET analyses. The acid modification was optimized by the application of response surface methodology using central composite design. Batch methodology showed that HA-DGS had higher CF uptake than DGS at variations of pH, temperature, contact time, adsorbent dosage and CF concentration. The Freundlich isotherm with
R
2
> 0.9795 was more applicable to both adsorbents, while DGS conformed to the pseudo-second-order kinetic (
R
2
> 0.9939) and HA-DGS (
R
2
> 0.9085), to the pseudo-first-order kinetics. Thermodynamics showed a physical and exothermic uptake of CF on the adsorbents. HA-DGS exhibited a maximum CF uptake of 125 mg/g, which was higher than most adsorbents reported in the literature. Quantum chemical parameters and condensed Fukui functions revealed efficient interaction between CF molecules and the prepared materials. Over 60% desorption of CF was obtained from the CF-loaded adsorbents using water and HCl solution. The results of this research showed HA-DGS as an efficient, low-cost, waste material that can be optimally valorized in the treatment of wastewater contaminated with CF.
Heteroleptic divalent metal complexes M(L) (bipy)(Y)•
O (where M = Mn, Co, Ni, and Zn; L = Schiff base; bipy = 2,2’-bipyridine; Y = OAc and
= 0, 1) have been synthesized from pyrimidine Schiff base ...ligand 3-{(
)-(4,6-dimethylpyrimidin-2-yl)iminomethyl} naphthalen-2-ol, 2,2’-bipyridine and metal(II) acetate salts. The Schiff base and its complexes were characterized by analytical (CHN elemental analyses, solubility, melting point, conductivity) measurements, spectral (IR, UV-vis,
H and
C-NMR and MS) and magnetometry. The elemental analyses, Uv-vis spectra and room temperature magnetic moment data provide evidence of six coordinated octahedral geometry for the complexes. The metal complexes’ low molar conductivity values in dimethylsulphoxide suggested that they were non-ionic in nature. The compounds displayed moderate to good antimicrobial and antifungal activities against
.
,
.
,
.
,
.
,
.
,
.
,
.
,
.
and
.
. The compounds also exhibited good antioxidant potentials with ferrous ion chelation and, 1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging assays. Molecular docking studies showed a good interaction with drug targets used. The structural and electronic properties of complexes were further confirmed by density functional theory calculations.
This study provides data on the concentrations and occupational risk of Cd, Pb, Cr, Ni, Cu, Co, Mn, Zn, and Fe in indoor dust from visual arts studios of nine tertiary institutions in southern ...Nigeria. The dust samples were digested in aqua regia and their metal concentrations were quantified by atomic absorption spectrometry. The concentrations of metals in dust from visual arts studios ranged from not detected (nd) to 91.5 mg kg
−1
Cd, 4.5 to 540 mg kg
−1
Pb, 0.10 to 1,100 mg kg
−1
Cr, 0.50 to 1,150 mg kg
−1
Ni, 10 to 15,600 mg kg
−1
Cu, 0.5 to 146 mg kg
−1
Co, 3.0 to 3,680 mg kg
−1
Mn, 93.5 to 9,600 mg kg
−1
Zn, and 853 to 237,000 mg kg
−1
Fe. The degree of contamination of the dust particles by metals was assessed by making use of the contamination/pollution index, geoaccumulation index and enrichment factor. These indices suggested that dusts from these visual arts studios were impacted with Cd, Pb, Cu, and Zn. The hazard index (HI) and cancer risk values relating to adults' exposure to metals in dust from these arts studios were within safe limits. Principal component analysis indicated that the sources of metal contamination in dust from these visual arts studios were related to inputs from constituents of the artist's materials and vehicular emissions.
The work reported the synthesis and characterisation of Fe
2+
, Co
2+
, and Ni
2+
complexes of 2-(4,6-dihydroxypyrimidin-2-ylamino)naphthalene-1,4-dione (HL). The spectroscopic and elemental analysis ...results obtained were consistent with the adoption of the formulas, ML
2
(M = Fe and Co) and ML
2
(H
2
O) (M = Ni) for the metal complexes. Electronic spectra and magnetic moments of the metal complexes corroborated octahedral geometry for Ni(II) complex and tetrahedral geometry for Fe(II) and Co(II) complexes. However, quantum-chemical calculations using density functional theory predicted trigonal bipyramidal geometry for Ni(II) complex and provided corroborative explanations for the structures of the other complexes. Conductance measurements in dimethylsulfoxide indicate that the complexes are non-electrolytes. The antimicrobial potential of the compounds was evaluated against
Staphylococcus aureus
,
Pseudomonas aeruginosa
,
Escherichia coli
,
Bacillus cereus
,
Proteus mirabilis
,
Klebsiella oxytoca
,
Aspergillus niger
,
A. flavus
, and
Rhizopus stolonifer
. The compounds gave moderate to good antimicrobial activity. However, the bacterial and fungal organisms were more susceptible to the cobalt complex and ligand respectively than the other compounds at concentration of 10 mg/mL. The compounds were also assessed for their antioxidant potential using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. The compounds displayed good DPPH radical scavenging activities. The nickel complex exhibited the best DPPH radical scavenging activity compared to the other compounds.
The potential toxic elements (Cu, Zn, Pb, Ni, Fe, Cr, Cd, Mn and Hg) were accumulated from rice grains and soil from an Ugbawka farm, Enugu State, Nigeria, which were determined to evaluate the ...potential health risk to rice consumers. The mean levels of metals found in soil (mg/kg) were as follows: Ni (0.57±0.24), Pb (2.44±0.17), Zn (3.35±2.05), Cu (0.71±0.33), Mn (37.72±10.97), Fe (13 856.6±31.43), Cr (2.51±0.98), Cd (0.51±1.36), and Hg (0.02±0.38); however metals found in rice grains (mg/ kg) were: Ni (0.81±0.72), Pb (0.94±0.70), Zn (8.22±2.97), Cu (0.59±0.42), Mn (13.30±4.56), Fe (13.28±0.73), Cr (15.00±10.00), Cd (0.36±0.07), and Hg (0.002±0.23). A small percentage (2.5%) of the soil samples were above the Chinese Maximum Allowable Concentration for cadmium in soil while cadmium and lead levels in the rice grains were above WHO permissible limit. Pearson’s correlations showed significant correlations amongst some metal pairs in soil and grains showing similarity in origin. The estimated daily intake of Pb was higher than the safety levels given by JECFA. Hazard Quotient for Pb and Total Hazard Index of all the metals were above one. This indicates possible potential health risk and adverse effect resulting from consumption of rice from Ugbawka farm.
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