Tharwat Selim

Prof. Dr. Tharwat Selim


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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Verified
Journal Article
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Amr HashemAmr Hashem
Amr Hashem
TSTharwat Selim
Tharwat Selim
MAMohammed H. Alruhaili
Mohammed H. Alruhaili
Samy SelimSamy Selim
Samy Selim
DADalal Hussien M. Alkhalifah
Dalal Hussien M. Alkhalifah
Salem S. SalemSalem S. Salem
Salem S. Salem
In the current study, prickly pear peel waste (PPPW) extract was used for the biosynthesis of selenium nanoparticles through a green and eco-friendly method for the first time. The biosynthesized SeNPs were characterized using UV-Vis, XRD, FTIR, TEM, SEM, EDX, and mapping. Characterization results revealed that biosynthesized SeNPs were spherical, polydisperse, highly crystalline, and had sizes in the range of 10–87.4 nm. Antibacterial, antifungal, and insecticidal activities of biosynthesized SeNPs were evaluated. Results revealed that SeNPs exhibited promising antibacterial against Gram negative (E. coli and P. aeruginosa) and Gram positive (B. subtilis and S. aureus) bacteria where MICs were 125, 125, 62.5, and 15.62 µg/mL, respectively. Moreover, SeNPs showed potential antifungal activity toward Candida albicans and Cryptococcus neoformans where MICs were 3.9 and 7.81 µg/mL, respectively. Furthermore, tested crud extract and SeNPs severely induced larvicidal activity for tested mosquitoes with LC50 and LC90 of 219.841, 950.087 mg/L and 75.411, 208.289 mg/L, respectively. The fecundity and hatchability of C. pipiens mosquito were significantly decreased as applied concentrations increased either for the crude or the fabricated SeNPs extracts. In conclusion, the biosynthesized SeNPs using prickly pear peel waste have antibacterial, antifungal, and insecticidal activities, which can be used in biomedical and environmental applications.

27 July 2022 in Insects
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Journal Article
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TSTharwat Selim
Tharwat Selim
IRIbrahim E. Abd-El Rahman
Ibrahim E. Abd-El Rahman
HMHesham A. Mahran
Hesham A. Mahran
HAHamza A. M. Adam
Hamza A. M. Adam
VIVincent Imieje
Vincent Imieje
Ahmed I. HasaballahAhmed I. Hasaballah
Ahmed I. Hasaballah
In this study, the crude extract and its isolated compounds from the stem bark of Annickia chlorantha were tested for their larvicidal, developmental, and repellent activity against the mosquito vector, Culex pipiens, besides their toxicity to the non-target aquatic organism, the zebrafish (Danio rerio). The acute larvicidal activity of isolated compounds; namely, palmatine, jatrorrhizine, columbamine, β-sitosterol, and Annickia chlorantha methanolic extract (AC), was observed. Developmentally, the larval duration was significantly prolonged when palmatine and β-sitosterol were applied, whereas the pupal duration was significantly prolonged for almost all treatments except palmatine and jatrorrhizine, where it shortened from those in the control. Acetylcholinesterase (AChE) enzyme showed different activity patterns, where it significantly increased in columbamine and β-sitosterol, and decreased in (AC), palmatine, and jatrorrhizine treatments, whereas glutathione S-transferase (GST) enzyme was significantly increased when AC methanolic extract/isolated compounds were applied, compared to the control. The adult emergence percentages were significantly decreased in all treatments, whereas tested compounds revealed non-significant (p > 0.05) changes in the sex ratio percentages, with a slight female-to-male preference presented in the AC-treated group. Additionally, the tested materials revealed repellence action; interestingly, palmatine and jatrorrhizine recorded higher levels of protection, followed by AC, columbamine, and β-sitosterol for 7 consecutive hours compared to the negative and positive control groups. The non-target assay confirms that the tested materials have very low toxic activity compared to the reported toxicity against mosquito larvae. A docking simulation was employed to better understand the interaction of the isolated compounds with the enzymes, AChE and GST. Additionally, DFT calculations revealed that the reported larvicidal activity may be due to the differing electron distributions among tested compounds. Overall, this study highlights the potential of A. chlorantha extract and its isolated compounds as effective mosquitocidal agents with a very low toxic effect on non-target organisms.

29 May 2025 in Scientific Reports
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FEFathy M. Elkady
Fathy M. Elkady
BBBahaa Mohammed Badr
Bahaa Mohammed Badr
ESEbrahim Saied
Ebrahim Saied
Amr HashemAmr Hashem
Amr Hashem
MAMohammed S. Abdulrahman
Mohammed S. Abdulrahman
MAMohammed Aufy
Mohammed Aufy
The unregulated administration of currently available antimicrobial agents resulted in overspreading of resistant microbial phenotypes. In this study, Mucor racemosus was used for biosynthesis of zinc oxide nanoparticles (ZnO NPs) through fungi-based ecofriendly approach. The biosynthesized of ZnO NPs was initially considered based on analytical practices including UV–vis spectroscopy and transmission electron microscopy (TEM). Additionally, their cytotoxicity and anticancer activity were analyzed using suitable cell lines and their antioxidant effect was also assessed. Microbiologically, their inhibitory activity was comparatively evaluated against various methicillinresistant Staphylococcus aureus (MRSA) and methicillinsensitive Staphylococcus aureus (MSSA). Characterization of ZnO NPs displayed a distinct maximum absorption peak at 320 nm appeared in the UV–vis. Also, TEM revealed predominantly spherical ZnO NPs with particle size distribution ranging from 15 to 55 nm (mean size ≃ 40 nm). The normal cell line (Wi-38) illustrated the biosafety of ZnO NPs, where results showed IC50 of 197.2 µg/mL. Furthermore, ZnO NPs exhibited promising suppressive activity on Hep-G2 cancerous cell with IC50 of 51.4 µg/mL. Besides, ZnO NPs displayed antioxidant activity where IC50 was 69.2 µg/mL. As well, the minimum inhibitory concentrations of ecofriendly ZnO NPs against the tested MRSA and MSSA isolates were ranged from 32 to 512 µg/mL. Also, their minimum bactericidal concentrations against the tested MSSA was in lower range, 32–1024 µg/mL, than the recorded range, 128–1024 µg/mL, against the MSSA. Also, the crystal violet (CV) assay showed an eradication potential of the biosynthesized ZnO NPs on MRSA and MSSA biofilm in a range of 23.24–73.96% and 6.63–74.1%, respectively. In conclusion, the ecofriendly synthesized ZnO NPs with antioxidant and anticancer activities demonstrated promising inhibitory effect on planktonic growth form of MRSA and MSSA clinical isolates with capability to eradicate their preformed biofilm. To achieve their full potential, future research needs to enhance the synthesis process to make ZnO NPs more uniform and scalable, as well as investigate their action mechanisms at the molecular level.

1 September 2021 in African Entomology
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Ahmed I. HasaballahAhmed I. Hasaballah
Ahmed I. Hasaballah
TSTharwat Selim
Tharwat Selim
MTM.A. Tanani
M.A. Tanani
ENEnas Nasr
Enas Nasr
In the current study, insecticidal activity, growth regulation, adult performance and repellency of petroleum ether, methanol, chloroform and ethanol extracts of Salix safsaf leaves were tested against third instar larvae of the housefly, Musca domestica. Different concentrations were applied through larval feeding to further investigate different biological aspects. Obtained data revealed that mortality percentages among the third instar larvae and pupal stage increased with increasing concentration. Moreover, larval and pupal duration was remarkably lengthened in a concentration-dependent manner vs the control. Furthermore, pupation and adult emergence percentages were inversely decreased with applied concentrations. The LC50 and LC90 values may be arranged as follows: petroleum ether (467.714 and 793.348 ppm), methanol (423.22 and 710.18 ppm), chloroform (533.55 and 942.88 ppm) and ethanol (384.90 and 712.33 ppm), respectively, compared with synthetic insecticide deltamethrin as a positive control that showed an LC50 value of 0.889 ppm and LC90 of 1.367 ppm. Overall, the toxic effects of methanol and ethanol extracts of S. safsaf could compete with the synthetic insecticide deltamethrin as a natural insecticide in the control. Different tested extracts affected the adult longevity, pre-maturation period, maturation period and post-maturation period in a delayed manner. Tested extracts exhibited potent repellency action that reached about 67.0 % for petroleum ether and 87.3 % for ethanol extract at a concentration of 800 ppm. Generally, S. safsaf leaf extracts may be considered as a potent candidate for housefly control and could be exploited as a component of integrated vector control strategies that may help in developing future safe and cheap insecticides of natural origin.

24 November 2024 in Sustainability
Verified
Journal Article
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SRSanad H. Ragab
Sanad H. Ragab
SAShatha I. Alqurashi
Shatha I. Alqurashi
MAMohammad M. Aljameeli
Mohammad M. Aljameeli
MTMichael G. Tyshenko
Michael G. Tyshenko
AAAhmed H. Abdelwahab
Ahmed H. Abdelwahab
TSTharwat Selim
Tharwat Selim
The potential range and distribution of insects are greatly impacted by climate change. This study evaluates the potential global shifts in the range of Gryllus bimaculatus (Orthoptera: Gryllidae) under several climate change scenarios. The Global Biodiversity Information Facility provided the location data for G. bimaculatus, which included nineteen bioclimatic layers (bio01–bio19), elevation data from the WorldClim database, and land cover data. For the near future (2021–2040) and far future (2081–2100) under low (SSP1-2.6) and high (SSP5-8.5) emission scenarios, the Beijing Climate Center Climate System Model (BCC-CSM2-MR) and the Institute Pierre-Simon Laplace Coupled Model Intercomparison Project (IPSL-CM6A-LR) were used. Assessing habitat gain, loss, and stability for G. bimaculatus under potential scenarios was part of the evaluation analysis. The results showed that the main environmental parameters affecting the distribution of G. bimaculatus were mean temperature of the driest quarter, mean diurnal temperature range, isothermality, and seasonal precipitation. Since birds, small mammals, and other insectivorous insects rely on G. bimaculatus and other cricket species as their primary food supply, habitat loss necessitates management attention to the effects on the food web. The spread of G. bimaculatus as a sentinel species in the food chain and its use in animal feeds are both impacted by habitat loss and gain.

27 December 2024 in Sustainability
Verified
Journal Article
Open access
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SRSanad H. Ragab
Sanad H. Ragab
AAAbeer Alkhaibari
Abeer Alkhaibari
JAJalal Alharbi
Jalal Alharbi
SASultan Mohammed Areshi
Sultan Mohammed Areshi
AMAbadi Mashlawi
Abadi Mashlawi
MKMohamed Kamel
Mohamed Kamel
Culex pipiens (Diptera: Culicidae) is a disease vector for the West Nile virus (WNV). Climate change impacts the disease transmission carried by mosquitoes, and it is partly to blame for the resurgence of mosquitoes as important disease vector insects. This study assessed the geographic range of Culex pipiens in the United States under both present and projected climatic scenarios, identifying the primary environmental factors influencing its distribution. Employing species distribution modeling (MaxEnt, Version 3.4.1) and occurrence data from the Global Biodiversity Information Facility, we examined the effects of key variables, including altitude, temperature seasonality (bio4), and annual precipitation (bio12), on habitat suitability for C. pipiens. The analysis revealed that altitude accounted for 60.3% of the model’s explanatory power, followed by temperature seasonality (31%) and annual precipitation (8.7%). Areas having low elevation and moderate temperature fluctuations were the most favorable for C. pipiens, with a predicted range extending across the Midwest and southeastern United States under present variables. Future projections for 2050 and 2070 under Representative Concentration Pathway (climatic change) scenarios suggest possible northward expansion in response to rising temperatures and altered precipitation patterns. The study highlights some shifts in C. pipiens distribution and the potential for increased disease transmission into new areas. This study serves as a catalyst for decision-makers to coordinate their management reaction and create more resilient and comprehensive strategies to safeguard human health.