Roba Attar

Dr. Roba Attar

orcid

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

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

Representative Publications

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11 June 2022 in Cellulose
Verified
Journal Article
Open access
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ASAbdu Subaihi
Abdu Subaihi
SASalhah D. Al-Qahtani
Salhah D. Al-Qahtani
RARoba Attar
Roba Attar
KAKholood Alkhamis
Kholood Alkhamis
HAHanan K. Alzahrani
Hanan K. Alzahrani
NENashwa Elmetwaly
Nashwa Elmetwaly
Textiles that respond to external stimuli with a change in their properties are referred to as “smart clothing”. Fluorescent textiles, which change color in response to light, are a subset of smart textiles. Herein, fluorescent and hydrophobic composite coatings were prepared and applied onto cellulose-based fabrics by the pad-dry-curing method. This innovative approach involves the integration of lanthanide-doped aluminum strontium oxide pigment phosphor nanoparticles into room temperature vulcanized silicone rubber. The pigment phosphor nanoparticles must be uniformly dispersed without agglomeration in order to create a transparent nanocomposite film. The pad-dry-cured film was successfully cured onto the cotton fabric under ambient conditions. The superhydrophobic activity of the fluorescent fibers improved with increasing pigment content. Both the ultraviolet protection and the antibacterial properties of the coated fibers were also investigated. The generated translucent fluorescent layer exhibited an absorbance peak of 358 nm and an emission peak of 517 nm. The fluorescent cotton fibers exhibited different colors, including white under visible daylight and intense green under ultraviolet devices, as described by the CIE Lab, as well as decay time, excitation and emission spectra. Both the mechanical performance and comfortability of the coated fibers were tested by measuring air permeability and bend length. The spectroscopic results of the treated fabrics are detailed using a scanning electron microscope and energy dispersive X-ray spectra. During ultraviolet stimulation, the coated cloth displayed a reversible and fast fluorescent photochromism that was not fatigued. The qualities of colorfastness were described, including washing, crocking, sweat, and light.

21 March 2022 in Biotechnology & Biotechnological Equipment
Verified
Journal Article
Open access
Mohammed Nabih BaeshenMohammed Nabih Baeshen
Mohammed Nabih Baeshen
RARoba Attar
Roba Attar
TBThamer A. Bouback
Thamer A. Bouback
AAAbdulaziz O. Albeshri
Abdulaziz O. Albeshri
NBNaseebh N Baeshen
Naseebh N Baeshen
AMArif Mohammed
Arif Mohammed
The emergence of superbugs and resistant pathogens poses a challenge in scientific and medical research as they threaten public health worldwide. Many herbal natural products currently used in therapies have been suggested to exert antimicrobial, antiviral and even virucidal activities against a vast majority of impervious pathogens. Rhazya stricta, a folk medicinal desert plant from Saudi Arabia was recently revealed to exhibit bactericidal activity against multidrug-resistant (MDR) microorganisms. The pandemic caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a threat to public health worldwide. Hence, we examined the antiviral activity of R. stricta against the virus. The R. stricta water extract was prepared at the traditional dose. The antagonistic effects of this extract against pathogens have been proven in previous studies, and those against SARS-CoV-2 were shown in the present study. Therefore, we explored the effects of the plant extracts and fractions against the virus for future drug development. All plant extracts showed antiviral effects against SARS-CoV-2 in the Vero E6 cell lines. Non-alkaloids showed the strongest effect against the virus, followed by weak base alkaloids and finally strong base alkaloids. A cytotoxicity assay was performed to explore the safest dose with the strongest antiviral effects. The non-alkaloid extract derived from R. stricta leaves is a promising antiviral candidate for the development of potential drugs with appropriate activity against COVID-19 and other life-threatening diseases.

27 January 2025 in International Journal of Biological Macromolecules
Verified
Journal Article
Closed access
Samy SelimSamy Selim
Samy Selim
MAMohammed S. Almuhayawi
Mohammed S. Almuhayawi
MAMohammed H. Alruhaili
Mohammed H. Alruhaili
ASAmna A Saddiq
Amna A Saddiq
ABAfra Mohammed Baghdadi
Afra Mohammed Baghdadi
SASOAD Khalil ALJAOUNI
SOAD Khalil ALJAOUNI

4 May 2022 in Molecules
Verified
Journal Article
Open access
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HHHeba ali Hassan
Heba ali Hassan
AHAhmed R. Hassan
Ahmed R. Hassan
Eslam A.R. MohamedEslam A.R. Mohamed
Eslam A.R. Mohamed
Ahmad Ayad Qatran Al-KhdhairawiAhmad Ayad Qatran Al-Khdhairawi
Ahmad Ayad Qatran Al-Khdhairawi
AKAlaa Karkashan
Alaa Karkashan
AAAhmed E. Allam
Ahmed E. Allam
(1) Background: Natural constituents are still a preferred route for counteracting the outbreak of COVID-19. Essentially, flavonoids have been found to be among the most promising molecules identified as coronavirus inhibitors. Recently, a new SARS-CoV-2 B.1.1.529 variant has spread in many countries, which has raised awareness of the role of natural constituents in attempts to contribute to therapeutic protocols. (2) Methods: Using various chromatographic techniques, triterpenes (1–7), phenolics (8–11), and flavonoids (12–17) were isolated from Euphorbia dendroides and computationally screened against the receptor-binding domain (RBD) of the SARS-CoV-2 Omicron variant. As a first step, molecular docking calculations were performed for all investigated compounds. Promising compounds were subjected to molecular dynamics simulations (MD) for 200 ns, in addition to molecular mechanics Poisson–Boltzmann surface area calculations (MM/PBSA) to determine binding energy. (3) Results: MM/PBSA binding energy calculations showed that compound 14 (quercetin-3-O-β-D-glucuronopyranoside) and compound 15 (quercetin-3-O-glucuronide 6″-O-methyl ester) exhibited strong inhibition of Omicron, with ΔGbinding of −41.0 and −32.4 kcal/mol, respectively. Finally, drug likeness evaluations based on Lipinski’s rule of five also showed that the discovered compounds exhibited good oral bioavailability. (4) Conclusions: It is foreseeable that these results provide a novel intellectual contribution in light of the decreasing prevalence of SARS-CoV-2 B.1.1.529 and could be a good addition to the therapeutic protocol.

24 November 2022 in Journal of Biomolecular Structure and Dynamics
Verified
Journal Article
Closed access
AKAlaa Karkashan
Alaa Karkashan
RARoba Attar
Roba Attar
Recently, a new variant B.1.1.529 or Omicron variant and its sub-variants (BA2.75, BA.5) of SARS-CoV-2 (Severe acute respiratory virus 2) have been reported with a larger number of mutations in the spike protein and particularly in the RBD (receptor-binding domain). The omicron (B.1.1.529) variant has aggravated the pandemic situation further and needs more analysis for therapeutic development. Keeping in view the urgency of the required data, the current study used molecular modeling and simulation-based methods to target the NRP1 (Neuropilin 1) protein to halt the entry into the host cell. Employing a molecular screening approach to screen the North-East African natural compounds database (NEANCDB) revealed Subereamine B with a docking score of −8.44 kcal/mol, Zinolol with the docking score of −8.05 while Subereamine A with a docking score of −7.88 kcal/mol as the best hits against NRP1. Molecular simulation-based further validation revealed stable dynamics, good structural packing, and dynamic residues flexibility index. Moreover, hydrogen bonding fraction analysis demonstrated the interactions remained sustained during the simulation. Furthermore, the total binding free energy for Subereamine B was −44.24 ±0.91 kcal/mol, for Zinolol −34.32 ±0.40 kcal/mol while for Subereamine A the TBE was calculated to be −41.78 ± 0.36 kcal/mol respectively. This shows that the two arginine-based alkaloids, i.e. Subereamine B and Subereamine A could inhibit the NRP1 more strongly than Zinolol. In conclusion, this study provides a basis for the development of novel drugs against SARS-CoV-2. Communicated by Ramaswamy H. Sarma

1 January 2024 in Brazilian Journal of Biology
Verified
Journal Article
Open access
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RARoba Attar
Roba Attar
The emergence of antibiotic resistance (AR) in bacteria is becoming an alarming health concern because it allows them to adapt themselves to changing environments. It is possible to prevent the spread of AR in many ways, such as reducing antibiotic misuse in human and veterinary medicine. Streptococcus pseudopneumoniae is one of these AR bacterial species that can cause pneumonia in humans and is responsible for high mortality and morbidity rates. It is oval shaped gram-positive bacterium that shows resistance to several antibiotics like penicillin, tetracycline, ciprofloxacin, erythromycin, and co-trimoxazale and no approved vaccine is available to overcome diseases of the pathogen. Thus, substantial efforts are necessary to select protective antigens from a whole genome of pathogens that are easily tested experimentally. The in silico designed vaccine was safe and potent in immunizing individuals against the aforementioned pathogens. Herein, we utilized a subtractive genomic approach to identify potential epitope-based vaccine candidates against S. pseudopneumoniae. In total, 50850 proteins were retrieved from the NCBI, representing the complete genome of S. pseudopneumoniae. Out of the total, CD-HIT analysis identified 1022 proteins as non-redundant and 49828 proteins as redundant and further subjected for subcellular localization in which bulk of proteins was located in the cytoplasm, with seven extracellular proteins (penicillin-binding protein, alpha-amylase, solute-binding protein, hypothetical protein, CHAP domain-containing protein, polysaccharide deacetylase family protein, hypothetical protein). Six immune cells epitopes (SNLQSENDRL, RNDSLQKQAR, NPTTTSEGF, KVKKKNNKK, AYSQGSQKEH, and SVVDQVSGDF) were predicted with the help of the IEDB server. To design a multi-epitopes vaccine these immune cell epitopes were together by GPGPG and adjuvant linker to enhance immune response efficacy. The 3D structure of the designed vaccine was modeled and conducted molecular docking and dynamic simulation studies were to check the binding efficacy with immune cells receptor and dynamic behavior of the docked complex. Finally, we concluded that the designed vaccine construct can provoke a proper and protective immune response against S. pseudopneumoniae.