Attia, Y. A., E. Abdelsalam, S. Saeed, M. S. M. Mohamed, and M. Samer, "Bioethanol Production from Potato Peels Using Saccharomyces cerevisiae Treated with ZnO and ZnO/g-C3N4 Nanomaterials", Egyptian Journal of Chemistry, vol. 65, issue 13, pp. 309 - 315, 2022. Abstract

Bioethanol is a promising biofuel produced from agricultural wastes. The problem is that the bioconversion of cellulose to bioethanol takes a long time for excellent results. Predominantly, efficient enzymes and active microorganisms (yeast) can enhance the enzymatic saccharification and fermentation bioprocesses, respectively. The addition of nutrients and electron acceptors in form of nanomaterials was found to modify the bioenvironment and to biostimulate the microorganisms to accomplish the target bioprocesses efficiently. The objective of this investigation was to increase bioethanol production from agricultural wastes using nanomaterials. In this study, the bioethanol production from potato peels (as an example of agricultural wastes) was increased using ZnO nanomaterials and ZnO/g-C3N4 nanomaterials with the concentration of 5, 10, 15, 50, 100, and 150 mg/L each as well as the control (without the addition of nanomaterials). It was hypothesized that yeast treatment with nanomaterials (nutrients) leads to biostimulate yeast cells and increases cell activity. Consequently, it is hypothesized that these procedures increase bioethanol production from potato peels over a shorter Hydraulic Retention Time (HRT), i.e., residence time. It was found that the biostimulation of the fungi (yeast) Saccharomyces cerevisiae using 150 mg/L of ZnO/g-C3N4 nanomaterials generated the highest bioethanol concentration of 33.2% compared to all other treatments. © 2022 National Information and Documentation Center (NIDOC)

Attia, Y. A., M. Samer, M. S. M. Mohamed, M. Salah, E. Moustafa, R. M. A. Hameed, H. Elsayed, and E. M. Abdelsalam, "Enhancing bioelectricity generation from wastewater in microbial fuel cells using carbon nanomaterials", Journal of Chemical Technology and Biotechnology, vol. 99, issue 5, pp. 1172 - 1180, 2024. Abstract

BACKGROUND: Microbial fuel cells (MFCs) offer a promising approach for treating wastewater and generating electrical energy simultaneously. However, their implementation in wastewater treatment plants is hindered by the limited electricity generation, often attributed to the electrolyte's high resistance. This study aimed to improve bioelectricity generation in MFCs by adding nanomaterials to the electrolyte to enhance conductivity. RESULTS: Three types of nanomaterials – carbon nanotubes (CNTs), graphitic carbon nitride (g-C3N4), and reduced graphene oxide (r-GO) – were synthesized and addition to the electrolyte at a concentration of 50 mg in 1.5 L. MFC performance was evaluated, employed a hydraulic retention time (HRT) of 140 h, and compared to a control with no nanomaterials added. The addition of nanomaterials significantly improved MFC performance. Compared to the control, the MFCs with CNTs, g-C3N4, and r-GO exhibited higher voltage: 1.301 V (CNTs), 1.286 V (g-C3N4), 1.280 V (r-GO) versus 0.570 V (control); increased power density: 14.11 mW m−3 (CNTs), 13.78 mW m−3 (g-C3N4), 13.66 mW m−3 (r-GO) versus 2.71 mW m−3 (control); enhanced areal power density: 21.06 mW m−2 (CNTs), 20.57 mW m−2 (g-C3N4), 20.39 mW m−2 (r-GO) versus 4.04 mW m−2 (control); and improved coulombic efficiency: 19.43% (CNTs), 19.19% (g-C3N4), 19.11% (r-GO) versus 8.54% (control). CONCLUSION: Incorporating nanomaterials into the MFC electrolyte significantly increased bioelectricity generation by 5.21 times and coulombic efficiency by 2.28 times compared to the control. This improvement is attributed to the high specific surface area of the nanomaterials, which facilitates the adhesion and growth of microorganisms around the anode, enhancing direct electron transfer. © 2024 Society of Chemical Industry (SCI). © 2024 Society of Chemical Industry (SCI).

Attia, Y. A., M. Samer, M. S. M. Mohamed, E. Moustafa, M. Salah, and E. M. Abdelsalam, "Nanocoating of microbial fuel cell electrodes for enhancing bioelectricity generation from wastewater", Biomass Conversion and Biorefinery, vol. 14, issue 1, pp. 847 - 858, 2024. Abstract

Microbial fuel cells (MFCs) are devices where bacteria generate electrical energy by oxidizing organic matter in wastewater. The implementation of MFCs on a commercial scale is limited due to electrode resistances, which are one of the key factors limiting electricity generation. This study presents a method to maximize the electrical power production from MFCs by coating the electrodes using nanomaterials which leads to prototyping novel electrodes having higher electrical conductivity than common electrodes. The voltage reached 1.234 V directly after operating the MFCs, with nanocoated electrodes, and showed voltage stability till the end of the 140 h interval with a peak value of 1.367 V with a maximum areal power density of 116 mW m−2 and a maximum volumetric power density of 15.6 mW m−3. However, the voltage of the control (without coating) was steadily increased to 0.616 V after 22 h with a maximum areal power density of 23.6 mW m−2 and a maximum volumetric power density of 3.2 mW m−3 then showed voltage stability till the end of the 140 h interval. It was found that the coulombic efficiency of the MFCs where its electrodes are coated with graphitic carbon nitride nanosheets was higher than graphene, carbon nanotubes, and the control in a descending order, respectively. By this method, it is possible to improve the electrical conductivity of the MFCs which results in increasing the generated electrical power by 4.9 times the conventional method. © 2022, The Author(s).

Tammam, A. M., M. S. M. Mohamed, and H. Moubasher, "Optimisation of Fungal Laccase Production from Monodictys castaneae", ASM Science Journal, vol. 18, 2023. Abstract

Laccases are copper-containing oxidase enzymes that have broad substrate specificity and applicability in industrial processes. The purpose of this work was to optimise laccase production by a certain endophytic fungus. Monodictys castaneae (Wallr.) Hughes was cultured and incubated using different nutritional and physiological factors affecting laccase production. It was found that the optimum physiological conditions for laccase production were 4 disc inoculum size, a 9-day fermentation period, pH 5, and 28°C. The enzyme was purified using acetone precipitation, gel filtration, and ion-exchange chromatography. The enzyme was identified as a monomeric protein with a molecular mass of 63 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Different concentrations of CuSO4 were used to stimulate laccase production and activity. A 0.15 g/l concentration of CuSO4 was the optimum dosage for laccase activity enhancement. For enzyme-guaiacol interaction, the optimal pH and temperature were 5.4 and 35 °C, respectively. The laccase activity was highly stimulated using 3 mM and 7 mM concentrations of chloride salts of Cd+2, Ca+2, Cr+2 and Fe+3, but the enzyme activity was slightly inhibited by 10 mM concentrations of these metal ions. According to all previous results, Monodictys castaneae showed promising potential as a producer of laccase. © (2023), (Akademi Sains Malaysia). All Rights Reserved.

Ouf, S. A., F. A. El-Amriti, M. A. Abu-Elghait, S. E. Desouky, and M. S. M. Mohamed, "Role of Plant Growth Promoting Rhizobacteria in Healthy and Sustainable Agriculture", Egyptian Journal of Botany, vol. 63, issue 2, pp. 333 - 359, 2023. Abstract

CONVENTIONAL agriculture plays a vital role in meeting the increasing demands for food which result from the continuous rising of the human population. Nowadays farmers use more and more amounts of chemical fertilizers and pesticides which have a bad influence on soil quality, the ecosystem, and the health of humans. Hence, it is important to explore other approaches to decrease the application of chemical fertilizers and enhance crop productivity. Inoculation of the crop with plant growth promoting rhizobacteria (PGPR) to augment sustainable agriculture production is another strategy that is eco-friendly and could be carried out in the long run. PGPR is a group of bacteria able to colonize the root of plants and increase their growth and yield. They help in increasing water absorption, suppress pathogens, and also enhance the uptake of nutrients from soil. Biochemical applications by which rhizobacteria can stimulate the growth of plants were discussed in this article; (i) bio-stimulants: represented by particular phytohormones synthesized by PGPR for e.g. auxins or indole acetic acid (IAA), cytokinins, gibberellic acid (GA) and ethylene, (ii) biofertilization: through helping the uptake of many nutrients from the environment e.g. biological nitrogen fixation, phosphate solubilization and production of siderophore, (iii) bioprotectants or biocontrol: by preventing plant diseases through antibiotic, lytic enzymes and/or hydrogen cyanide (HCN) production. © 2023 National Information and Documentation Center (NIDOC).

Elmelegy, S. A., M. S. Khalil, and M. S. M. Mohamed, "Efficient biodegradation and detoxification of Congo red via newly isolated Bacillus strains", Egyptian Journal of Chemistry, vol. 67, issue 1, pp. 67 - 76, 2024. Abstract

Pollution with xenobiotic compounds such as congo red (CR) is a serious problem in the environment. In the present study, an attempt has been made to screen and isolate a potential local bacterial strains from dye contaminated area for decolorization of CR dye as an example of (azo-dye). Out of 52 bacterial isolates demonstrated the ability to grow on CR dye as a sole carbon source, three bacterial isolates showed high dye decolorization percentage ranged from 65.8 to 81.5% after 4 days of incubation (λ max of CR 498 nm). The selected bacterial strains were identified as Bacillus licheniformis S2, Bacillus amyloliquefaciens S12 and Bacillus subtilis S50 based on morphological, molecular and biochemical characteristics. A set of experiments were carried out to optimize the degradation ability of the selected isolates under different physicochemical conditions such as different concentrations of CR, pH range, temperatures and static and shaking incubation. The results revealed that the three Bacillus species were able to degrade CR more efficiently at static conditions compared to shaking conditions and the optimum CR dye concentration for the three isolates was 100 μM at 37 ºC and pH 7.0. Spectroscopic techniques were performed to evaluate the isolates degradation abilities and to identify the degradation by-products by UV-Vis and GC-MS, indicated the complete degradation of congo red to other less-toxic compounds after 6 days of incubation. The phytotoxicity test on Vicia faba and Triticum aestivum seeds revealed that all bacterial degraded dye metabolites had almost negligible effect on both plant germinations compared to untreated dye, which indicating the successful detoxification of CR dye. Therefore, the selected Bacillus strains from this study might be useful in the treatment of industrial effluent contaminated with synthetic dyes. © 2024 National Information and Documentation Center (NIDOC).

Elarabi, N. I., AA Abdelhadi, A. A. Nassrallah, M. S. M. Mohamed, and H. A. R. Abdelhaleem, "Biodegradation of isoproturon by Escherichia coli expressing a Pseudomonas putida catechol 1,2-dioxygenase gene", AMB Express, vol. 13, issue 1, 2023. Abstract

The phenylurea herbicides are persistent in soil and water, necessitating the creation of methods for removing them from the environment. This study aimed to examine the soil microbial diversity, searching for local bacterial isolates able to efficiently degrade the phenylurea herbicide isoproturon, 3-(4-isopropylphenyl)-1, 1-dimethylurea (IPU). The best isolates able to effectively degrade IPU were selected, characterized, and identified as Pseudomonas putida and Acinetobacter johnsonii. The catechol 1, 2-dioxygenase enzyme's catA gene was amplified, cloned, and expressed in E. coli M15. The Expressed E. coli showed high degradation efficiency (44.80%) as analyzed by HPLC after 15 days of inoculation in comparison to P. putida (21.60%). The expression of the catA gene in P. putida and expressed E. coli was measured using quantitative polymerase chain reaction (qPCR). The results displayed a significant increase in the mRNA levels of the catA gene by increasing the incubation time with IPU. Hydrophilic interaction chromatography (HILIC) mass spectrometry analysis revealed that three intermediate metabolites, 1-(4-isopropylphenyl)-3-methylurea (MDIPU), 4-Isopropylaniline (4-IA) and 1-(4-isopropylphenyl) urea (DDIPU) were generated by both P. putida and expressed E. coli. In addition, IPU-induced catA activity was detected in both P. putida and expressed E. coli. The supernatant of both P. putida and expressed E. coli had a significant influence on weed growth. The study clearly exhibited that P. putida and expressed E. coli were capable of metabolizing IPU influentially and thus could be utilized for bioremediation and biodegradation technology development. © 2023, Springer-Verlag GmbH Germany, part of Springer Nature.

Arabi, D. S., O. Hamdy, Z. A. Abdel-Salam, M. S. M. Mohamed, and M. Abdel-Harith, "Utilization of Spectrochemical Analysis and Diffuse Optical Techniques to Reveal Adulteration of Alike Fish Species and Their Microbial Contamination", Food Analytical Methods, vol. 15, issue 4, pp. 1062 - 1073, 2022. Abstract

Fish products are essential sources of animal proteins and numerous nutrients required for healthy human nutrition worldwide. However, some types of low-priced fish may look very similar to some other expensive types, and usually, it is not easy to differentiate between them for inexperienced customers. Moreover, in some markets, adulterating such high-priced fish types through its substitution by cheaper ones or mixing with bacterially spoiled ones, mostly when sold as fish fillets, is sometimes common. Certainly, fish microbial contamination in open markets represents serious hazards for people’s public health. Accordingly, seeking easy and fast fish fraud detection methods and their microbial contamination disclosure is crucial. Currently, available techniques are costly, time-consuming, and requiring special laboratories. In the present work, laser-induced fluorescence (LIF), as a spectrochemical analytical technique and diffuse optical measurements, has been used to discriminate between fillets of low-priced Tilapia and expensive Nile Perch and disclose microbial contamination in any. The experimental data have been analyzed and evaluated using the principal component analysis (PCA), partial least square regression (PLSR), and receiver operatic characteristic (ROC) methods. The results demonstrated the high advantages of optical and spectrochemical techniques in the fast and accurate discrimination between the two fish species. Moreover, LIF spectral band obtained at 490 nm showed a difference in microbial load between both species. © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.

Abdelkader, A. A., M. S. Khalil, and M. S. M. Mohamed, "Simultaneous biodegradation of λ-cyhalothrin pesticide and Vicia faba growth promotion under greenhouse conditions", AMB Express, vol. 12, issue 1, 2022. Abstract

λ-cyhalothrin is a widely used synthetic pyrethroid insecticide and its persistence in plant, soil and water exerts a detrimental effect on humans as well as the environment. There are many studies regarding isolated bacteria capable of degrading λ-cyhalothrin in vitro. However, limited work has been done examining the microbial degradation of λ-cyhalothrin together with plant growth promotion under greenhouse conditions. In this study, 43 bacterial strains were isolated from heavily polluted soil with λ-cyhalothrin by the enrichment technique. The plant growth promotion characteristics of all isolates were evaluated. The results revealed that five isolates were potential in λ-cyhalothrin biodegradation at high concentration (1200 mg/L) within only 24 h together with their high plant growth promotion abilities. The morphological, biochemical and 16S rDNA sequence analyses identified the isolates as Bacillus subtilis strains. The GC/MS analysis revealed that the selected isolates reached high levels of degradation after only two days, the degradation percentage ranged from 95.72 to 99.52% after 48 h of incubation. Furthermore, the degradation pathway for complete detoxification and metabolism of λ-cyhalothrin was established. Moreover, greenhouse experiment was conducted, the results indicate that the application of seed coat significantly enhanced Vicia faba seedling growth and caused an increase from 38.4 to 40.2% percentage of fresh and dry weight, respectively compared to untreated control. All isolates were effective to remove the pesticide residues in Vicia faba seedlings and recorded the highest degradation percentage of 83.79 under greenhouse conditions. Therefore, it can be concluded that the Bacillus subtilis strains isolated in this study have a dual potential role in complete mineralization of λ-cyhalothrin residues in vivo as well as effective biofertilization for future use in sustainable agriculture. © 2022, The Author(s).

Saeed, S., M. Samer, M. S. M. Mohamed, E. Abdelsalam, Y. M. A. Mohamed, S. H. Abdel‑Hafez, and Y. A. Attia, "Implementation of graphitic carbon nitride nanomaterials and laser irradiation for increasing bioethanol production from potato processing wastes", Environmental Science and Pollution Research, vol. 29, issue 23, pp. 34887 - 34897, 2022. Abstract

Agricultural and agro-industrial wastes (e.g., potato peel waste) are causing severe environmental problems. The processes of pretreatment, saccharification, and fermentation are the major obstacles in bioethanol production from wastes and must be overcome by efficient novel techniques. The effect of exposing the fungi (yeast) Saccharomyces cerevisiae to laser source with the addition of graphitic carbon nitride nanosheets (g-C3N4) with different concentrations on bioethanol production was investigated through the implementation of a batch anaerobic system and using potato peel waste (PPW). Dichromate test was implemented as quantitative analysis for quantification of the bioethanol yield. The benefits of this test were the appearance of green color indicating the identification of ethanol (C2H5OH) by bare eye and the ease to calculate the bioethanol yield through UV–visible spectrophotometry. The control sample (0.0 ppm of g-C3N4) showed only a 4% yield of bioethanol; however, by adding 150 ppm to PPW medium, 22.61% of ethanol was produced. Besides, laser irradiations (blue and red) as influencing parameters were studied with and without the addition of g-C3N4 nanomaterials aiming to increase the bioethanol. It was determined that the laser irradiation can trigger the bioethanol production (in case of red: 13.13% and in case of blue: 16.14% yields, respectively) compared to the control sample (in absence of g-C3N4). However, by adding different concentrations of g-C3N4 nanomaterials from 5 to 150 ppm, the bioethanol yield was increased as follows: in case of red: 56.11% and, in case of blue: 56.77%, respectively. It was found that using fungi and exposing it to the blue laser diode source having a wavelength of 450 nm and a power of 250 mW for a duration of 30 min with the addition of 150 mg L−1 of g-C3N4 nanomaterials delivered the highest bioethanol yield from PPW. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.