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1.
Prep Biochem Biotechnol ; 54(2): 226-238, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37210635

RESUMO

Peptidases, which constitute about 20% of the global enzyme market, have found applications in detergent, food and pharmaceutical industries, and could be produced on a large scale using low-cost agro-industrial waste. An acidophilic Bacillus cereus strain produced acidic peptidase on binary-agro-industrial waste comprising yam peels and fish processing waste at pH 4.5 with high catalytic activity. A five-variable central composite rotatable design of a response surface methodology was used to model bioprocess conditions for improved peptidase production in solid-state fermentation. Data generated was leveraged as the basis for applying the novel Manta-ray foraging optimization-linked feed-forward artificial neural network to predict bioprocess conditions optimally. Results obtained from the optimization experiments revealed a significant coefficient of determination of 0.9885 with low-performance error. The bioprocess predicted a peptidase activity of 1035.32 U/mL under optimized conditions set as 54.8 g/100 g yam peels, 23.85 g/100 g fish waste, 0.31 g/100 g CaCl2, 47.54% (v/w) moisture content, and pH 2. Peptidase activity was improved 5-fold, and was stable for 240 min between pH 2.5 and 3.5. Michaelis-Menten kinetics revealed a Km of 0.119 mM and a catalytic efficiency of 45462.19 mM-1 min-1. The bioprocess holds promise for sustainable enzyme-driven applications.


Assuntos
Resíduos Industriais , Peptídeo Hidrolases , Fermentação , Bacillus cereus , Algoritmos
2.
Prep Biochem Biotechnol ; 53(6): 690-703, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36269079

RESUMO

Serratia marcescens strain UCCM 00009 produced a mixture of gelatinase and keratinase to facilitate feather degradation but concomitant production of prodigiosin could make waste feather valorization biotechnologically more attractive. This article describes prodigiosin fermentation through co-valorization of waste feather and waste frying peanut oil by S. marcescens UCCM 00009 for anticancer, antioxidant, and esthetic applications. The stochastic conditions for waste feather degradation (WFD), modeled by multi-objective particle swarm-embedded-neural network optimization (ANN-PSO), revealed a gelatinase/keratinase ratio of 1.71 for optimal prodigiosin production and WFD. Luedeking-Piret kinetics revealed a non-exclusive, non-growth-associated prodigiosin yield of 9.66 g/L from the degradation of 88.55% waste feather within 96 h. The polyethylene glycol (PEG) 6000/Na+ citrate aqueous two-phase system-purified serratiopeptidase demonstrated gelatinolytic and keratinolytic activities that were stable for 240 h at 55 °C and pH 9.0. In vitro evaluations revealed that the prodigiosin inhibited methicillin-resistant Staphylococcus aureus at IC50 of 4.95 µg/mL, the plant-pathogen, Sclerotinia sclerotiorum, at IC50 of 2.58 µg/mL, breast carcinoma at IC50 of 0.60 µg/mL and 2,2-diphenyl-1-picryl-hydrazyl hydrate (DPPH) free-radical at IC50 of 96.63 µg/mL). The pigment also demonstrated commendable textile dyeing potential of fiber and cotton fabrics. The technology promises cost-effective prodigiosin development through sustainable waste feather-waste frying oil co-management.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Prodigiosina , Animais , Plumas , Heurística , Serratia marcescens
3.
Environ Monit Assess ; 193(11): 718, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34642861

RESUMO

The surface resistivity method was used to appraise the protectivity of hydrogeological units and corrosivity of the top soil in Obot Akara County, southern Nigeria. A total of 28 vertical electrical sounding (VES) was undertaken in the area using the Schlumberger electrode configuration. The results of the VES data interpretation reveal 3 to 4 geoelectric layers in the study area. The resistivity of the first layer interpreted as the Motley top soil ranges from 34.7 to 929.7 Ωm with a mean value of 381.1 Ωm. The third layer, with a resistivity range of 99.4 to 2716.7 Ωm, constitutes the aquifer unit in most communities in the area, with an average thickness of 58.3 m, while the fourth layer penetrated in most communities has a resistivity range of 216.1 to 1475.7 Ωm with a mean value of 657.5 Ωm. The longitudinal conductance and resistivity reflection coefficient of the aquifer protective layers vary from 0.04 to 0.76 mhos and - 0.74 to 0.93, respectively. Analysis of these results shows that 89.3% of the hydrogeological units in the area is weakly/poorly protected, 10.7% has moderate to good protection, while 85.7% of the top soil at the sounding stations is noncorrosive and 14.3% is slightly to moderately corrosive. The implication of these results is that most of the hydrogeological units in the area are likely prone to contamination in particular by some ferrugenized materials from the overlying layers. Also, underground metal storage tanks and galvanized and steel pipes can be buried in the topmost layer in most communities in the area without any risk of failure. Although these findings are very promising especially in groundwater management and exploitation in the area, hydrogeochemical and microbiological analyses of groundwater samples from available boreholes are recommended to corroborate the results.


Assuntos
Cáusticos , Água Subterrânea , Monitoramento Ambiental , Substâncias Protetoras , Solo
4.
Environ Monit Assess ; 187(4): 156, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25736831

RESUMO

The geophysical-based integrated electrical conductivity (IEC) and the groundwater hydraulic confinement-overlying strata-depth to water table (GOD) techniques were used to assess vulnerability levels of aquifers and the extent of aquifer protection in Abi, Nigeria. The IEC indices was generated from constrained one dimensional (1D) inversion of vertical electrical sounding (VES) and two dimensional (2D) electrical resistivity tomography (ERT) data, acquired randomly in the area. The GOD indices were sourced from existing geologic data within the area. Results showed that IEC values vary from <0.1 S in the weakly protected areas to >2.0 S in the strongly protected areas. The GOD indices vary from <0.3 in the lowly vulnerable areas to 0.6 in the highly vulnerable areas. Thus, the groundwater resources in the area need to be properly managed for sustainability and such management practices have been suggested.


Assuntos
Água Subterrânea/química , Poluição da Água/análise , Monitoramento Ambiental/métodos , Geologia , Nigéria , Poluição da Água/estatística & dados numéricos
5.
Heliyon ; 8(3): e09027, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35284665

RESUMO

The inefficiencies and uncertainties surrounding solutions from existing inversion methods have necessitated investigation for more efficient techniques for the inversion of ill-posed magnetic problems. In this study, the Social Spider Optimization (SSO) algorithm has been modified, adopted and successfully used in modelling physical characteristics of magnetic anomalies originating from simple-shaped geologic structures. The study, aimed at testing the capacity and efficiency of the SSO algorithm to model magnetic data of varying complexity, was successfully conducted on both synthetic data with varying levels of noise and real field data obtained from mining fields in Senegal and Egypt. To assess the mathematical nature of the inverse problem considered, error energy maps were produced for each model parameter pairs in the synthetic examples. These maps enabled the pre-assessment of the resolvability model parameter for the ill-posed problem. In addition, uncertainty analysis aimed at providing insight to the reliability of the obtained solutions was carried out using the Metropolis-Hastings (M-H) sampling algorithm. Results show that the procedure converges fast and generates accurate results even when confronted with constrained multi-parameter non-linear inversion problems. Its outstanding converging speed and accuracy of the results reveal it as an excellent procedure for overcoming agelong problems of local optimal solutions associated with pre-existing algorithms. The consistency of the results with actual values affirms the efficacy of the new procedure which is pioneering in geophysical literature. It is therefore a stable and efficient tool for performing geophysical data inversion and is therefore recommended for use in inverting geophysical data with higher complexities like seismic reflection and gravity data, that require many corrections to be performed before reliable geological interpretations can be made.

6.
Biotechnol Rep (Amst) ; 35: e00746, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35707314

RESUMO

A strain of Stenotrophomonas acidaminiphila, isolated from fermenting bean-processing wastewater, produced alkaline protease in pretreated cassava waste-stream, but with low yield. Strain improvement by alternate combinatorial random mutagenesis and bioprocess optimization using comparative statistical and neural network methods enhanced yield by 17.8-fold in mutant kGy-04-UV-25. Kinetics of production by selected mutant modeled by logistic and modified Gompertz functions revealed higher specific growth rate in mutant than in the parent strain, likewise volumetric and specific productivities. Purification by PEG/Na+ citrate aqueous two-phase system recovered 73.87% yield and 52.55-fold of protease. Its activity was stable at 5-35% NaCl, 45-75°C, and was significantly enhanced by 1-15 mM sodium dodecyl sulfate (SDS). The protease was inhibited by low concentrations of phenyl-methyl-sulfonyl fluoride but was activated by 1-5 mM Mn2+ suggesting a manganese-dependent serine­protease. The 45.7 kDa thermo-halo-stable alkaline protease demonstrated keratinolytic and blood-stain removal potentials showing prospects in textile and detergent industries, respectively.

7.
Niger Med J ; 60(4): 211-218, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31831942

RESUMO

BACKGROUND: Too many artemisinin-based combination therapies (ACTs) are available, thus creating a dilemma on the most preferred for the treatment of malaria. AIM: We compared the effect of six ACTs in mitigating Plasmodium-induced hepatorenal toxicity in experimental malaria. MATERIALS AND METHODS: Forty adult male Swiss mice allotted into eight groups: Group 1 (normal control [NC] uninfected and untreated), Group 2 (parasitized nontreated - [PNT]), and Groups 3-8 received Plasmodium berghei inoculum. After 72 h, the initial parasitemia was established. Groups 3-8 were administered oral therapeutic doses of artesunate-amodiaquine (AA), artesunate-mefloquine (AM), artesunate-sulfadoxine-pyrimethamine (ASP), artemisinin-piperaquine (AP), dihydroartemisinin-piperaquine (DP), and artemether-lumefantrine (AL) per kg bodyweight, respectively, as standard regimen, and final parasitemia determined. Animals were euthanized via chloroform inhalation and blood collected for hepatorenal analysis. Liver and kidney were dissected out for histology. RESULTS: Parasitemia was significantly (P < 0.05) decreased in tests compared to PNT, except in ASP group. Liver enzymes were significantly (P < 0.05) increased in PNT compared to tests and NC. Hyperplastic cells and portal tract inflammation were prominent in ASP group, but mild to moderate in other treated groups. Urea-creatinine were significantly (P < 0.05) increased in PNT compared to treated groups. The Na+ and Cl- were significantly (P < 0.05) reduced in PNT, with significantly (P < 0.05) increased K+ compared to NC and treated groups. Glomerulonephritis and glomerulus splitting was observed in PNT, while moderate distortions were observed in treated groups. The AA and AM groups had good kidney histoarchitecture. CONCLUSION: Parasitemia decreased in all the treatment groups except in PNT and ASP groups which had severe hepatorenal distortions. Hepatorenal histoarchitecture were mildly distorted in the AA, AM and AL-administered groups with lower hepatorenal indices comparable to NC. The least elevated liver enzymes were in AA and AM. In decreasing order ASP > DP > AL > AP > AM > AA.

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