Green synthesis of Ag nanoparticles from Argemone mexicana L. leaf extract coated with MOF-5 for the removal of metronidazole antibiotics from aqueous solution.

There are growing concerns about the toxicity of metronidazole (MNZ) antibiotics in wastewater, which must be removed. This study used AgN/MOF-5 (1:3) to investigate the adsorptive removal of MNZ antibiotics from wastewater. Green synthesis of Ag-nanoparticles was from Argemone mexicana leaf aqueous extract blended with the synthesized MOF-5 in 1:3 by proportion. The adsorption materials were characterized by scanning electron microscope (SEM), N2 adsorption-desorption analysis, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The surface area increased due to the appearance of micropores. Besides, the efficiency of AgN/MOF-5 (1:3) for MNZ removal was evaluated by adsorption properties, including key influential parameters (adsorbent dosage, pH, contact time, etc.) and adsorption mechanism, kinetics/isotherms. The results from the adsorption process conformed to pseudo-second-order kinetics (R2 = 0.998) and well fitted with the Langmuir isotherm having 191.1 mg/g maximum adsorption capacity. The adsorption mechanism of AgN/MOF-5 (1:3) was due to the interactions of π-π stacking, Ag-N-MOF covalent bonding and hydrogen bonding. Thus, AgN/MOF-5 (1:3) is a potential adsorbent for the removal of aqueous MNZ. The adsorption process is endothermic, spontaneous, and feasible based on the obtained thermodynamic parameter of ΔHO and ΔSO having 14.72 and 0.129 kJ/mol respectively.

Biochemical Studies on the Colorectal Tissues of Wistar Rats Treated with Methanol Leaf and Stem Bark Extracts of Annona muricata (Soursop).

Annona muricata (AMC), is a tropical plant species of the Annonaceae family known for its medicinal uses in ameliorating and/or protecting several organs and tissues in the body. In this study we elucidated the influence of the methanol extracts of AMC leaf and stem bark on the biochemical and histological integrity of the colorectum. Different doses (100, 200, 400, 600, and 800mg of extract/kg body weight) of methanol extracts of the leaves and stembark were orally administered to adult male Wistar rats of average weight (100 - 150 g) for 28 days. At the end of the experimental period, the rats were sacrificed and colorectal tissues harvested for analyses. Adenosine triphosphatase (ATPases), lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G6PD) activities, and tissue protein (TP) concentration, were evaluated by colorimetric method using appropriate test kits. The results in the colorectal tissue analysed showed that total ATPase, LDH and G6PD (energy markers) activities increased significantly in the groups which received methanol leaf and stem bark extracts of AMC when compared with control. However, a general decrease was observed in TP and Na+/K+-ATPase activity but there was a twist in Na+/K+-ATPase activity in stem bark doses of 200mg/kg and 400mg/kg which showed significant increases in dose dependent manner when compared with the control. Even though G6PD activity showed fluctuating patterns for both extracts, the highest dose (800mg/kg) reflected the most significant increase when compared with the control. The histology confirmed the toxicological results by the biochemical parameters. Under the condition of this study, we inferred that the methanol leaf and stem-bark extracts of AMC may significantly influence the enzymes by reducing and increasing total ATPase and Na+/K+-ATPase activities depending on the doses and administration should therefore depend on the desired outcome.

Biochemical investigation of the upstream anti-sickling mechanisms of soursop (Annona muricata): 15-acetyl guanacone as an inhibitor of deoxyhaemoglobin polymerisation.

Current sickle cell disease (SCD) therapies are limited and inefficient. The ethnomedicinal values of Annona muricata in the treatment of SCD, leading to this present research. Leaves and fruits of Annona muricata were processed using solvent extraction and partitioning; aqueous, chloroform and ethyl acetate fractions. In vitro (anti-oxidant and anti-sickling), in silico, quantitative (amino acids) and kinetic simulation experiments were done. 15-acetyl guanacone, was used, in silico against 2,3-bisphosphoglycerate (2, 3-BPG) mutase and deoxyhaemoglobin. The ethyl acetate and chloroform fractions better NO● scavengers, iron-chelators and ferric reducing. In vitro unsickling (UT50) had ethyl acetate = 5 h and methanol = 7 h. Chloroform fraction had EC50 1.00 mg/mL (EC50 = 546 mg/mL) to 10.00 mg/mL (EC50 = 99 mg/mL). EC50 and IC50 of ethyl acetate fraction had steady-decrease. At higher concentration, chloroform fraction had higher Bmax (1.48 × 1021 U/mL) and higher Kd (3.66 × 1019 mg/mL), whereas, at a lower concentration, the ethyl acetate fraction demonstrated higher Bmax (7.23 × 1012 U/mL) and lower Kd (2.12 × 1011 mg/mL); The relative affinity (BP) of chloroform fraction increased progressively with concentration. The amino acid profile revealed rich concentrations glycine, valine, leucine, lysine, phenylalanine, histidine, arginine, and tryptophan. From the in silico experiments, 15-acetyl guanacone specifically targeted the A and B chains, with greater affinity for the beta subunit. This suggested that 15-acetyl guanacone might be able to prevent the polymerisation of deoxyHbSS, induce an allosteric conformational change that increases the oxygen affinity, and decrease the cellular 2, 3-BPG concentration.Communicated by Ramaswamy H. Sarma.

Proximate composition, phytochemical analysis, and in vitro antioxidant potentials of extracts of Annona muricata (Soursop).

Numerous bioactive compounds and phytochemicals have been reported to be present Annona muricata (Soursop). Some of these chemical compounds have been linked to the ethnomedicinal properties of the plant and its antioxidant properties. The aim of this study was to assess the proximate composition, phytochemical constituents and in vitro antioxidant properties of A. muricata using standard biochemical procedures. The defatted Annona muricata crude methanolic extracts of the different parts of the plant were used for the estimation of proximate composition and phytochemical screening. The crude methanolic extracts of the different parts of the plant were also fractionated using solvent-solvent partitioning. Petroleum ether, chloroform, ethyl acetate, methanol, and methanol-water (90:10) were the solvents used for the fractionation. The different fractions obtained were then used to perform in vitro antioxidant analyses including, 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, ferric reducing properties, and hydroxyl radical scavenging ability. The leaf methanolic extract had a higher lipid content, whereas its chloroform fraction demonstrated a better ability to quench DPPH free radical. The root-bark methanol-water, leaf methanol, fruit pulp chloroform, and leaf petroleum ether fractions demonstrated potent ferric reducing properties. The leaf and stem-bark petroleum ether fractions demonstrated better hydroxyl-free radical scavenging abilities. The leaf and fruit pulp of Annona muricata have a very potent antioxidant ability compared to the other parts of the plant. This can be associated with the rich phytochemicals and other phytoconstituents like phenols, flavonoids, alkaloids, and essential lipids, etc. Significant correlations were observed between the antioxidant status and phytochemicals present. These results thus suggest that some of the reported ethnomedicinal properties of this plant could be due to its antioxidant potentials.

Addition of multimodal therapy to standard management of steady state sickle cell disease.

Most people on folic acid to boost erythropoiesis and prophylactic antimicrobials, the standard management of steady state sickle cell disease (SCD), have unacceptable numbers of crises. The objective of this study was to evaluate the effects of adding multimodal therapy with potassium thiocyanate and omega-3 fatty acids to the standard management of steady state SCD. Pre- and post-treatment numbers of crises and other disease indices were compared in 16 HbSS individuals on folic acid and paludrine after 12 months of adding eicosapentaenoic acid 15 mg/kg/day, docosahexaenoic acid 10 mg/kg/day, and potassium thiocyanate 1-2 mL/day, each milliliter of which contained 250 mg of thiocyanate and 100 micrograms of iodine to prevent hypothyroidism: a possible side-effect due to competitive inhibition of the transport of iodide into the thyroid gland by thiocyanate. Median number of crises reduced from 3/yr to 1/yr (P < 0.0001). There was no evidence of impaired thyroid function. Plasma level of tri-iodothyronine improved (P < 0.0001). Steady state full blood count and bilirubin level did not change significantly. The findings suggest that addition of potassium thiocyanate and eicosapentaenoic and docosahexaenoic acids to standard management of steady state SCD reduces the number of crises. This observation needs to be evaluated in larger studies.

Pilot study of omega-3 fatty acid supplements in sickle cell disease.

In a previous retrospective study, it was observed that the greater the amounts of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the blood, the lesser the number of complications of sickle cell disease (SCD) and the higher the steady state haemoglobin level. SCD causes ischaemia-reperfusion injury and inflammation; which can be ameliorated by a metabolite of DHA that down-regulates expression of pro-inflammatory genes. The objectives of this prospective pilot study were to evaluate the effects of DHA and EPA supplements in SCD, and test the hypothesis that these effects are mediated partly by reducing inflammation. Oral DHA and EPA supplements were given to 16 SCD patients for 6 months. We then compared pre- and post-supplementation values of number of crisis, steady state Hb, plasma unconjugated bilirubin and three indices of inflammation: plasma interleukin-6, blood neutrophil and platelet counts. There was a significant reduction in the plasma level of unconjugated bilirubin, and the number of sickle cell crisis; but not in the markers of inflammation. The pilot data suggest that DHA and EPA supplements reduce the number of crisis and steady state haemolysis in SCD; but provide no evidence that these effects are mediated by reducing inflammation.