University Frères Mentouri Constantine 1

Several biotechnological and industrial applications are based on the use of various microbial enzymes. Today, amylases are one of the most demanded enzymes due to their high productivity yield and thermostability. The potential use of Geotrichum candidum PO27 for the production of α-amylase was investigated for its ability to utilize olive pomace (OP) waste as a carbon source. Plackett and Burman Design (PBD) and Response Surface Methodology (RSM) using Central Composite Design (CCD) approaches were used to obtain optimal conditions for enzyme production. Cultivation parameters, including pH, inoculum, various carbon and nitrogen sources, and other supplements, were screened by solid-state fermentation (SSF) at 60 °C. Under optimal conditions (moisture content 24.77%, malt extract 1.84 g%, and CaCl₂ 1.84 g%), the maximum production reached 412.94 U/g, which was in agreement with the statistical model prediction (421.32 U/g). The model showed a 2.27-fold increase in α-amylase production compared with the initial medium (181.61 U/g). Peak α-amylase production was achieved after 40 h of incubation at pH 5.53, and sugar concentrations ranged from 10.87 mg/ mL to 5.537 within the first 6 h of culture. Due to the low substrate cost and short incubation time of the strain, Geotrichum candidum PO27 α-amylase may be of significant commercial value to industries requiring enzymatic hydrolysis of starch.

Electrocatalytic nitrate reduction (NO₃RR) methods are promising in addressing nitrate (NO₃^-) pollution and green ammonia (NH₃) synthesis.However, the NO₃RR process is complex, and overcoming the high energy barrier of the reaction is crucial for improving NH₃ selectivity.In this study, Cu₂O was combined with two-dimensional copper(II) tetrakis (4-carboxyphenyl) porphyrin (Cu-TCPP) nanosheets.The Cu-TCPP/Cu₂O/CF tandem catalytic electrode was reported, demonstrating enhanced catalytic performance through synergistic interactions across multiple active sites.After 4 h of electrocatalytic nitrate reduction tests, the Cu-TCPP/Cu₂O/CF catalysts achieved NH₃ yields up to 0.0937 mmol h^-1 cm^-2 and NH₃ faraday efficiency (FE_NH3) up to 90.22% at a potential of -1 V vs RHE.In addition, the source of nitrate reduction activity was analyzed under different initial conditions, in situ Raman characterization and the NO₃RR pathway on the catalyst surface was investigated.Interestingly, the Zn-nitrate (Zn-NO₃^-) battery constructed with Cu-TCPP/Cu₂O/CF as the cathode showed a FE_NH3 of 98.89% and an NH₃ yield of 199.25 μmol h^-1 cm^-2.The constructed Zn-NO₃^- battery could be discharged continuously for more than 24 h while synthesizing NH₃ efficiently.Cu-TCPP/Cu₂O/CF has good potential for practical applications and provides a reference for subsequent work on metal-organic framework tandem catalysts.

This study presents an innovative approach to eco-friendly pesticide removal by investigating the biodegradation of tribenuron-Me (TBM) using a novel bacterial strain, Microbacterium paraoxydans BS3-TBM, isolated from TBM-contaminated agricultural soil.Identified through 16S rRNA anal., this strain demonstrated remarkable potential by utilizing TBM as its sole carbon source.Under optimal conditions-TBM concentration of 5.25 mg/L, inoculum volume of 9.9% (volume/volume), and pH of 5.008-Microbacterium paraoxydans BS3-TBM achieved a 99% degradation of TBM within just 5 days, as predicted by an Artificial Neural Network-Genetic Algorithm (ANN-GA) model.Anal. of the degradation intermediates revealed the formation of N-methyl-4-methoxy-6-methyl-1,3,5-triazin-2-amine (N-MTA) and Me 2-(aminosulfonyl) benzoate (MASB) due to TBM hydrolysis.Importantly, both N-MTA and MASB were completely removed following biol. treatment using the bacterial strain Microbacterium paraoxydans BS3-TBM.Toxicity assays using the microalgae Nannochloropsis gaditana confirmed a significant reduction in the toxicity of the treated TBM solution compared to the untreated sample.These findings highlight the effectiveness and environmental safety of using Microbacterium paraoxydans BS3-TBM for TBM removal, offering a promising solution for sustainable pesticide degradation