Graft copolymerization is a promising method for properties modification of natural polymers. Cassava starch, a natural polymer was extracted using wet extraction route. Part of the obtained starch was pre-gelatinized at above 70oC and esterified using phthalic anhydride. CaO (catalyst) was prepared by calcining snail shell powder in a muffle furnace at 800oC for 4 h. The native and pregelatinized/phthalated starch solutions were grafted with acrylonitrile at 120oC in the presence of CaO catalyst. The prepared CaO catalyst was characterized using SEM, EDS, TGA, XRD, and FTIR for surface assessment, elemental evaluation, thermal degradation, amorphosity/crystallinity determination, and functional group evaluation, respectively. The SEM-EDS of the prepared CaO catalyst revealed spherical shape and the elemental compositions. The FTIR spectra of the grafted native cassava starch copolymer and grafted phthalated cassava starch copolymer revealed the existence of C equivalent to N-peak at 2364 and 2262 cm-1, respectively which is an evidence of grafting. The surface of the native cassava starch grafted copolymer granules was eroded with cracks, while that of the phthalated cassava starch grafted copolymer showed coagulated and coerced morphology. The XRD result of the native cassava starch grafted copolymer revealed one major sharp peak at angle 2 theta=25o while that of the phthalated cassava starch grafted copolymer revealed numerous peaks. The TGA analysis revealed that the phthalated cassava grafted copolymer framework was completely broken at 500oC unlike the native cassava starch grafted copolymer whose complete decomposition was about 420oC. It was observed that the modified samples had improved features over the native sample.

Graft copolymerization is a promising method for properties modification of natural polymers.Cassava starch, a natural polymer was extracted using wet extraction route.Part of the obtained starch was pre-gelatinized at above 70 o C and esterified using phthalic anhydride.CaO (catalyst) was prepared by calcining snail shell powder in a muffle furnace at 800ºC for 4 h.The native and pregelatinized/phthalated starch solutions were grafted with acrylonitrile at 120 o C in the presence of CaO catalyst.The prepared CaO catalyst was characterized using SEM, EDS, TGA, XRD, and FTIR for surface assessment, elemental evaluation, thermal degradation, amorphosity/crystallinity determination, and functional group evaluation, respectively.The SEM-EDS of the prepared CaO catalyst revealed spherical shape and the elemental compositions.The FTIR spectra of the grafted native cassava starch copolymer and grafted phthalated cassava starch copolymer revealed the existence of C≡N-peak at 2364 and 2262 cm -1 , respectively which is an evidence of grafting.The surface of the native cassava starch grafted copolymer granules was eroded with cracks, while that of the phthalated cassava starch grafted copolymer showed coagulated and coerced morphology.The XRD result of the native cassava starch grafted copolymer revealed one major sharp peak at angle 2θ=25 o while that of the phthalated cassava starch grafted copolymer revealed numerous peaks.The TGA analysis revealed that the phthalated cassava grafted copolymer framework was completely broken at 500 o C unlike the native cassava starch grafted copolymer whose complete decomposition was about 420 o C. It was observed that the modified samples had improved features over the native sample.

Chitosan nanoparticles ( CNp ), nickel-chitosan nanoparticles ( Ni-CNp ), and copper-chitosan nanoparticles ( Cu- CNp ) were synthesized from pure chitosan. The samples were characterized using Energy-Dispersive X-ray Spectroscopy (EDS), Transmission Electron Microscopy (TEM), Fourier-Transform Infra -Red (FTIR), and X-ray Diffraction (XRD). Their inhibitory and bactericidal potentialities were tested against Salmonella sp. and Shigella sp. at 1000, 500, 250, and 125 mg mL -1 . The EDS results revealed the elemental composition of the samples. At 1000 mg mL -1 : against Salmonella sp. , MIC values for CNp , Ni-CNp , and Cu-CNP were 20.4 +/- 0.64, 25.6 +/- 0.71, and 34.3 +/- 0.57 mgmL -1 , respectively; for Shigella sp., the MIC values for CNp , Ni-CNp , and Cu-CNP were 20.8 +/- 0.64, 24.2 +/- 0.21, and 23.57 +/- 0.58 mgmL -1 , respectively. This trend was also observed at 500, 250, and 125 mg mL -1 . The results established that the incorporation of heavy metals into CNp induced more antimicrobial potency against Salmonella sp. and Shigella sp.

The study focused on the preparation and antibacterial evaluation of chitosan (CHT), carboxymethyl chitosan (CMC) and their respective metal composites. All the samples were characterized using Fourier Transform Infrared (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The antibacterial potentials of the samples were tested against Escherichia coli, Klebsiella sp., Pseudomonas aeruginosa A, and Pseudomonas aeruginosa B. SEM results revealed different changes in samples surfaces as a result of chemical modification. EDS revealed the presence of Ni and Cu in the composites. XRD spectra of CMC showed that the crystalline region of CHT was reduced by the modification. The antibacterial results indicated that the samples had inhibitory and bactericidal effects against Escherichia coli and Klebsiella sp. at 1000, 500, and 250 mg mL-1. The study showed that CMC and CMC-metal composites performed better at inhibiting the growth of microorganisms than CHT and CHT-metal composites.

•Synthesis and characterization of hydroxyapatite (HAp).•Ca(II) favorable adsorption sites of HAp for the removal of Cu(II) and Ni(II) ions.•Exothermic adsorption process of Cu(II) and Ni(II) ions.•Outer sphere mechanism of the adsorption of Cu(II) and Ni(II) ions.•Cu(II) and Ni(II) ions adsorbed from simulated and real industrial waste.

This study assesses the mineral levels in water, sediment, and fishes from Ekiti State University pond, Nigeria; and investigates the metal levels in locally made and imported feeds. Four fish samples (tilapia I and II; catfish I and II) from the pond were dissected to obtain livers, gills, and tissues. The water, sediments, feeds, and fish parts were analyzed using a Flame Photometer (Corning 400) and an Atomic Absorption Spectrophotometer (Buck Scientific 210). The levels of Na, K, Ca, Fe, Cu, Zn, and Mn in the pond water are 10.00, 8.89, 3.02, 6.67, 0.03, 0.25, and 0.18 mg/L, respectively. The concentrations of Na, K, Ca, Fe, Cu, Zn, and Mn in the sediment are 2.52, 4.21, 2.72, 29.78, 0.11, 0.95, and 0.42 mg/kg, respectively. The levels of metals in the feed samples (locally made and imported) range as follows: Na (47.56 - 76.06); K (181.06 - 190.05); Ca (95.43 - 244.53); Fe (2.38 - 4.16); Cu (0.17 each); Zn (1.03 - 1.31); Mn (0.59 - 0.83 mg/kg). The concentrations of metals in the liver, gill, and tissue range as follows: Na (4.90 - 54.56); K (5.02 - 69.07); Ca (21.42 - 522.57); Fe (0.72 - 9.54); Cu (0.06 - 0.44); Zn (0.24 - 1.17); Mn (0.02 - 0.52 mg/kg). However, Cd, Pb, Cr, Ni, and Co were not detected in all the samples. The results showed that the mineral levels in the fishes are within the permissible limits of the World Health Organization (WHO) and Standard Organization of Nigeria (SON).

Amino acids composition of Thryonomysswingerianus is reported. Whereas protein values (g100g-1) were liver (74.1), kidney (91.5), heart (84.6); corresponding total amino acid values were 93.5, 83.2 and 80.6. True protein from the crude protein of the samples ran thus: liver>kidney>heart. Of the twenty parameters reported on, liver was best in 12/20 (60.0%), kidney and heart both shared the second position of 4/20(20%) each. Among the essential amino acids, leucine predominated in both liver (7.96g100g-1 protein) and kidney (8.11g100g-1 protein) but valine (6.21g100g-1 protein) predominated in the heart. The P-PER values were; P-PER1: 2.78 (liver), 2.91(kidney), 0.716 (heart) and P-PER2: 2.71 (liver), 2.90 (kidney), 0.564 (heart). However, there was a reverse between liver and kidney in the EAAI values with liver (92.0) > kidney (90.2) > heart (87.6) with corresponding BV values of 88.5 > 86.6 > 83.7. In the amino acids scoring pattern, Ser was limiting in liver (0.533) and heart (0.394) but Thr (0.490) in kidney in whole hen’s egg score comparison; in FAO/WHO scoring standards, Thr was limiting in liver (0.988) and kidney (0.625) but Leu (0.459) in heart. In pre-school requirements, liver recorded no limiting amino acid whereas Thr was limiting in kidney (0.735) and Leu was limiting in the heart (0.486). T.swingerianus red viscera was compared with the red viscera of livestock animals (cattle, sheep and pork) as well as FAO/WHO/UNU standards for total essential amino acids. Our results when compared with the livestock red viscera (without Trp) and FAO/WHO/UNU (g100g-1 protein), we have heart: grasscutter/cattle/sheep/pig:45.3 /46.0/42.7/46.6; kidney: grasscutter/cattle/sheep/pig: 47.6/43.8/42.5/46.7; liver: grasscutter/cattle/sheep/pig: 50.7/47.7/41.5/47.5 and grasscutter liver/kidney/heart/ FAO/WHO/UNU:50.7/47.6/45.3/32.8 showing that all the red viscera values in T.swingerianus were better than the essential amino acids in the FAO/WHO/UNU standards and livestock red viscera. Statistical values showed that significant differences existed among the samples at r=0.01.

Starches were isolated from cocoyam (Xanthosoma sagittifollium), white yam (Dioscorea rotundata) and bitter yam (Dioscorea dumentorum). Starch modification was carried out using acetic anhydride and phthalic anhydride. The native and modified starches were characterized using Fourier Transformed Infra-red Spectroscopy (FTIR) for identification of the functional groups. Functional properties such as water absorption capacities, oil absorption capacity, swelling power, solubility, gelation temperature, least gelation capacity, amylose content and pH were determined using standard procedures. Acetylation increased the water absorption capacity, oil absorption capacity, swelling power, amylose content, and solubility of the starches while phthalation decreased water absorption capacity, oil absorption capacity, swelling power, and solubility of the starches. Native cocoyam starch has the highest gelation temperature (85 °C) while Acetylated bitter yam has the lowest gelation temperature (74 °C). The pH of the native and modified starches was within the range of 4.14 − 6.55. Phthalation and acetylation increased the bulk density of the starches. Native cocoyam, white yam, and bitter yam starches had the lowest gelation concentration (6%). Modification of native starches will improve the usage of starch in food and non-food applications.

Bioflocculants of microbial origin have the advantage of being safe, biodegradable and harmless to the environment. Production of bioflocculant by two fungi isolates and the factors affecting its production were investigated in this study. Primary screening of fungi for the production of bioflocculants, efficiencies and conditions for the optimum production of the bioflocculants were determined using standard microbiological and chemical methods. Aspergillus flavus MCB 271 and Aspergillus niger MCBF 08 were the best bioflocculant producers among the fourteen fungal isolates screened. Aspergillus flavus optimally produced bioflocculant with glucose and peptone as sole carbon and nitrogen sources respectively. Calcium ions (Ca2+) at 78.4% served as best cation sources for bioflocculant production with optimal pH of 7 and temperature of 40°C. Aspergillus niger MCBF 08 produced bioflocculant optimally when the media had peptone as a nitrogen source and maltose as a sole carbon source. The two species achieved the maximum flocculating activity of 97% (A. flavus MCBF 271) and 86% (A. niger MCBF 08) at pH values of 7 on the 3rd day of the study and caused a reduction in bacterial load of the wastewater samples by 58.73% and 60.85% respectively. These bioflocculants are thus potential replacement for synthetic flocculants conventionally used for wastewater treatment.

Batch experiments were conducted to evaluate the removal of Pb(II) ions from aqueous solutions using chemically and thermally activated cow dung (CTAC) ash and non-chemically but thermally activated cow dung (NTAC) ash under various experimental conditions. The optimum pH for the adsorption process using CTAC and NTAC was 5, while the optimum times using CTAC and NTAC were 240 and 180 min, respectively. Freundlich, Temkin, and Langmuir isotherm models were used to analyze the generated adsorption data. The Freundlich model had the highest coefficient of determination (R2) values that ranged from 0.989 to 0.999. The values of separation factor (RL) deduced from Langmuir isotherm were between 0 and 1 for both CTAC and NTAC ashes for the whole temperature range, which indicated favourable adsorption. Adsorption of the Pb(II) ions followed the pseudo-second-order kinetic model based on the R2 values that approached unity. Thermodynamic analyses revealed that the ΔH° values for CTAC and NTAC ashes were -8.69 and -11.39 kJ/mol, respectively, which indicated that ion adsorption was exothermic. Negative ∆S° values for the two adsorbents showed that the level of entropy was low at the solid/solvent interface during the adsorption process.

In this research, Bauhinia monandra seed and pod were investigated for the first time as a source for bioenergy production.Proximate analysis revealed that the biomass seed contains high volatile matter of 88.96 % and pod 92.64 %, the low ash content of 3.16 % for the seed and 0.89 % for the pod, with fixed carbon of 1.87 % for seed and 0.71 % for the pod.The ultimate analysis showed carbon, sulfur, and hydrogen are 41.45 %, 1.79 % and 6.28 % for the seed, while the pod had 42.25 %, 1.77 %, and 6.21 % respectively.Higher Heating Value ranges from 14.26 -14.69 MJ/kg were obtained for the biomass using three mathematical formulas.The Pyrolysis behavior of the biomass revealed four degradation peaks attributed to the removal of water molecules and the degradation of hemicellulose, cellulose, and lignin respectively.The kinetic parameters (activation energy (Ea) and frequency factor (A) determined from TG/DTG data revealed a relatively high Ea (35.5 -41.56 KJ/mol).The structural composition of the seed indicated 43.50 %, cellulose, 20.00 % hemicellulose, 19.50 % lignin, and 16.00 % extractive material, and pod had 37.50 % cellulose, 33.50 %

Background: Over exposure to Ultra Violet (UV) radiation is one of the most significant external stress-inducing factors resulting into occurrence of skin pigmentation among others in human body. The biological implication of such disorders is not only limited to premature skin aging and cancer, but also resulted into economic loss of perishable agricultural products. Methods: Methanol extracts of ten (10) medicinal plants with skin health traditional history were selected for this study. The biological profile of the extracts was assessed in an in-vitro system using colorimetric assays: tyrosinase inhibition, Ferric-ion Reducing Antioxidant Power (FRAP), Trolox Equivalent Absorbance Capacity (TEAC) and Fe II-induced microsomal lipid peroxidation. Results: Representative of asteraceae such as Laggera pterodonta (S3); Ageratum conyzoides (S4) and Chromolaena odorata (S5), while Euphorbia convoluloides (S8) were found to possess good anti- tyrosinase activity (IC50 = 177.50; 125.08; 167.58; 161.92) μg/ml respectively, in which the rate of formation of dopachrome proceeded via pseudo second order kinetic using the Largergren model. Other notable inhibition of oxidative stress displayed by the methanol extracts includes S7 (FRAP = 1905.12 ± 2.85 µM AAE/g); S1 & S6 (TEAC = 2163.48 ± 2.80; 1044.35 ± 28.99) µM TE/g, while S7 & S9 showed highest inhibitory activities on Fe II-induced microsomal lipid peroxidation (IC50 = 33.625; 35.125) µg/ml, respectively in competitive manner to that of the commercial anti-oxidant EGCG (IC50 = 36.250 µg/ml). Conclusion: The outcome of the biological properties of the selected plant extracts in this study suggested the existence of relationship between the traditional claims and the scientific data therein.

Chitosan, a useful biopolymer, was obtained from pulverized shells of blue crabs via demineralization, deproteination and de-acetylation. The chitosan was converted to nanoparticles using sodium tripolyphosphate (TPP) . The FTIR spectrum of chitosan nanoparticles showed various functional groups, such as hydroxyl, carbonyl, and amine among others, as expected in chitosan. The SEM analysis revealed clusters of crystals at the surfaces, while TEM showed a very smooth and fine surface morphology. The particle size was estimated at < 200nm. The XRD spectrum showed shifting of the 2Ɵ peaks angles 10 and 20 for normal chitosan to 17 and 25 for the chitosan nanoparticles. The TGA and its derivative (DTGA) showed that the biopolymer was thermally stable.

Gliricidia sepium and Gliricidia sepium Cellulose were used for the removal of disperse yellow 211 dye from aqueous solutions. The adsorbents were characterized using different instrumental analyses, and thereafter subjected to batch adsorption process. The adsorbents physical properties are similar in density, Gliricidia sepium has higher ash and silica contents compared with Gliricidia sepium cellulose. The Fourier Transform Infrared Spectroscopy (FTIR) revealed the functional groups present, while Scanning Electron Microscopy (SEM) analysis revealed changes inherent by the removal of lignin and hemicellulose from Gliricidia sepium to obtain Gliricidia sepium cellulose. Point zero charge for Gliricidia sepium biomass and Gliricidia sepium cellulose were observed at pH 4.2 and 6.0 respectively. The quantity of disperse yellow 211 dye adsorbed was strongly dependent on pH and temperature. The adsorption system using Gliricidia sepium and its cellulose were best described by pseudo-second order kinetic model with correlation coefficient (R 2 ) of 0.945 and 0.997, respectively. Based on the high correlation coefficient, adsorption using Gliricidia sepium obeyed Langmuir isotherm while Gliricidia sepium cellulose followed Freundlich isotherm. The underutilized Gliricidia sepium in its crude form and as cellulose has proven to be a good adsorbent for the removal of dispersed yellow 211 dye.