Rasha Gomma Gomma

Dr. Rasha Gomma Gomma


Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

View All Publications
10 December 2020 in Horticulturae
Verified
Journal Article
Open access
PDF file
IEIman El-Sayed
Iman El-Sayed
RGRasha Gomma Gomma
Rasha Gomma Gomma
EEEman F. El-Haggar
Eman F. El-Haggar
RErasha el-ziat
rasha el-ziat
DSDina M. Soliman
Dina M. Soliman
Although goldenrod (Solidago canadensis) is considered an invasive plant in many countries, it is a global cut-flower species. In addition, demand for goldenrod has increased significantly in recent years. Thus, the present study aimed to evaluate the response of Solidago canadensis cv. Tara to brassinosteroids (BRs) at levels of 0.10−3, 10−6, and 10−8 M, and chitosan at 0, 100, 150, and 200 mg/L as a foliar application to increase the quality and quantity of production, and its polyphenolic compounds. Moreover, antibacterial activity and genetic polymorphism for both untreated and the optimally treated goldenrod were investigated. The results showed that the highest mean of growth characteristics was found when plants were treated with BRs at 10−8 M, whereas the longer vase life was obtained using 200 mg/L chitosan. Furthermore, higher pigment values, N, P, K, and total phenolic content, antioxidant capacity, chlorogenic acid, and rutin content were detected on plants treated with 200 mg/L chitosan. In addition, foliar application with 200 mg/L chitosan caused higher antibacterial activity among the control and BRs. The optimal treatment of BR at 10−8 M (89%) showed a low genetic similarity, based on sequence-related amplified polymorphism (SRAP) analysis, comparable with the control and 200 mg/L chitosan. BR at 10−8 M and 200 mg/L chitosan showed a significant enhancement of growth parameters. As a result, it can be concluded that goldenrod, as a herb extract, shows significant promise as a natural preservative in pharmaceutical, food, and cosmetic products.

22 April 2022 in Journal of Genetic Engineering and Biotechnology
Verified
Journal Article
Open access
PDF file
RGRasha Gomma Gomma
Rasha Gomma Gomma
MFMohamed Fadel
Mohamed Fadel
YYYehya A. Youssef
Yehya A. Youssef
HTHanan Taie
Hanan Taie
NANivien A. Abosereh
Nivien A. Abosereh
MMMohamed Marzouk
Mohamed Marzouk
During the last decade, enormous research efforts have been directed at identifying potent microorganisms as sustainable green cell factories for eco-friendly pigments. Talaromyces atroroseus has recently been shown to excrete large amounts of azaphilone mycotoxin-free red pigment mixture comprising some known coloring components together with many uncharacterized metabolites. In this study, a new Talaromyces atroroseus isolate was identified via sequencing of the fragment of the nuclear ribosomal gene cluster containing internal transcribed spacers and 5.8S rRNA gene. The parameters that affected the level of pigment production were optimized in uncommon static conditions of culture and genetic improvement, via γ-irradiation, to improve pigment yield. Moreover, chemical characterization using LC/MS and skin safety test of the target pigment mixture were precisely conducted to maximize its benefits as a natural and safe red pigment for wool fabrics. Molecular identification via the sequencing of the ITS of the rDNA encoding gene cluster revealed that the fungal isolate TRP-NRC was T. atroroseus TRP-NRC (deposited in GenBank under accession number MW282329). In the static conditions of culture, pigment production was dramatically enhanced to 27.36 g/L in an optimum yeast malt peptone medium of 2% mannitol at pH 2−4.5 and 30 °C for 7 days of incubation. Under exposure to a 400-Gy γ-radiation dose, pigment yield was increased to a 3-fold level higher than that recorded for the wild type. Based on the inter-simple sequence repeats (ISSR), as a molecular marker tool, the wild-type T. atroroseus TRP-NRC strain and its mutants were discriminated. The UHPLC/HRESI-MS analytical tool characterized 60 metabolites, including many unknown molecules, at appropriate concentrations. It is worthy to note that four mitorubrin derivatives were identified for the first time in T. atroroseus, i.e., mitorubrinolamine acetate, dihydro-PP-O, mitorobrinal, and mitorubrinol. The range of irritation indexes (0−0.1) demonstrated an adequate skin safety after the direct local application of the pigment mixture. Finally, the pigment mixture exhibited a remarkably good dyeing ability in wool fabrics, with high-fastness properties. Because of its sustainable and economic production, the target red pigment mixture may be applied in the future in textile, food, cosmetics, or different pharmaceutical industries after extensive conventional safety and toxicity studies, which are currently under consideration.

12 August 2022 in Journal of Genetic Engineering and Biotechnology
Verified
Journal Article
Open access
PDF file
SNShaimaa A. Nour
Shaimaa A. Nour
GEghada el-sayed
ghada el-sayed
HTHanan Taie
Hanan Taie
MTMaha Taimour
Maha Taimour
Ahmed Fikry El-sayedAhmed Fikry El-sayed
Ahmed Fikry El-sayed
RGRasha Gomma Gomma
Rasha Gomma Gomma
The production of industrial enzymes such as xylanase using sufficient cost-effective substrates from potent microorganisms is considered economically feasible. Studies have reported castor cake (Ricinus communis) as the most potent and inexpensive alternative carbon source for production of xylanase C by using Aspergillus terreus (A. terreus). A. terreus strain RGS Eg-NRC, a local isolate from agro-wastes, was first identified by sequencing the internal transcribed spacer region of a nuclear DNA encoding gene cluster deposited in GenBank (accession number MW282328). Before optimization of xylanase production, A. terreus produced 20.23 U/g of xylanase after 7 days using castor cake as a substrate in a solid-state fermentation (SSF) system that was employed to achieve ricin detoxification and stimulate xylanase production. Physicochemical parameters for the production of xylanase were optimized by using a one-variable-at-a-time approach and two statistical methods (two-level Plackett–Burman design and central composite design, CCD). The maximum xylanase yield after optimization was increased by 12.1-fold (245 U/g). A 60–70% saturation of ammonium sulfate resulted in partially purified xylanase with a specific activity of 3.9 IU/mg protein. At 60 °C and pH 6, the partially purified xylanase had the highest activity, and the activation energy (Ea) was 23.919 kJmol. Subsequently, antioxidant capacity and cytotoxicity tests in normal Ehrlich ascites carcinoma human cells demonstrated xylooligosaccharides produced by the xylanase degradation of xylan as a potent antioxidant and moderate antitumor agent. Further investigations with sodium dodecyl sulfate polyacrylamide gel electrophoresis then determined the molecular weight of partially purified xylanase C to be 36 kDa. Based on the conserved regions, observations revealed that xylanase C belonged to the glycosyl hydrolase family 10. Next, the xylanase-encoding gene (xynC), which has an open reading frame of 981 bp and encodes a protein with 326 amino acids, was isolated, sequenced, and submitted to the NCBI GenBank database (accession number LC595779.1). Molecular docking analysis finally revealed that Glu156, Glu262, and Lys75 residues were involved in the substrate-binding and protein-ligand interaction site of modeled xylanase, with a binding affinity of −8.7 kcal. mol−1. The high production of safe and efficient xylanase could be achieved using economical materials such as Ricinus communis.

12 April 2024 in Agronomy
Verified
Journal Article
Open access
PDF file
KLKreema A. El Lebody
Kreema A. El Lebody
RGRasha Gomma Gomma
Rasha Gomma Gomma
GEghada el-sayed
ghada el-sayed
SHShaymaa Hussein
Shaymaa Hussein
Fall armyworm, Spodoptera frugiperda, is a serious agricultural pest native to tropical and subtropical regions of the Western Hemisphere and has invaded Africa and further spread into most countries of Asia within two years. In Egypt, researchers have conducted thorough investigations into the behavior of the fall armyworm and various methods to manage its impact. This study aims to further our understanding of the genetic diversity of fall armyworm populations in Egypt. By collecting specimens from five provinces across the country, we sought to analyze their genetic makeup. Through examination of partial sequences of the mitochondrial cytochrome oxidase subunit I (COI), we identified three distinct haplotypes. Phylogenetic analysis suggests that the primary sources of Spodoptera frugiperda in Egypt likely stem from both Asian and African origins. Employing the PCR-RFLP technique on the complete COI sequence, we were able to discern genotype patterns within the fall armyworm population. Our findings indicate the presence of two distinct strains—the Corn and Rice strains—within Egypt. This research contributes essential insights into the genetic diversity of insects in Egypt, providing valuable knowledge that can inform more effective strategies for managing this agricultural pest.

1 January 2020 in Egyptian Pharmaceutical Journal
Verified
Journal Article
Closed access
PDF file
RGRasha Gomma Gomma
Rasha Gomma Gomma
NANivien A Abo-Sereh
Nivien A Abo-Sereh
Bigad KhalilBigad Khalil
Bigad Khalil
Background and objective Invertase, one of the most important enzymes used in industrial and pharmaceutical applications, has been produced from different Aspergillus spp. Statistical and mathematical tools [response surface methodology (RSM)] have been carried out to optimize culture conditions to facilitate maximum enzyme production. This investigation aims to screen the ability of some Aspergillus spp. to produce invertase enzyme, to optimize the culture parameters, and to detect the genetic diversity between them. Materials and methods A total of five fungal strains were tested for the production of invertase. The most promising strain was selected for optimization. Optimization experiments were carried out to obtain maximum enzyme production, and a molecular marker (RAPD-PCR) was used to differentiate between these strains. Results and conclusion Some Aspergillus spp. were examined to produced invertase enzyme after 2 days of cultivation. Aspergillus niger recorded the highest enzyme production (6.8 U/ml). Ten RAPD-PCR primers were used to differentiate between Aspergillus spp. A total of 131 bands were amplified in the five strains of Aspergillus spp. Based on RAPD-PCR analysis, the highest similarities obtained between A. parasiticus and A. niger showed 75%. Moreover, the RAPD-PCR technique is a good tool for differentiation between the Aspergillus spp. To optimize culture condition, RSM was used to increase invertase production by A. niger. Temperature, pH, and incubation time dramatically affect invertase yield. A combination of these factors (pH 5, 35°C, and incubation for 72 h) was optimum for maximum production of invertase (8.2 U/ml). Our results employed RSM to elucidate the combination of effective factors such as temperature, pH, and incubation time to obtain a high yield of an important enzyme, invertase, from A. niger, used as a promising candidate for industrial applications.

28 June 2022 in Egyptian Journal of Chemistry
Verified
Journal Article
Closed access
NSNivien Abd-Rahman Abo Serih
Nivien Abd-Rahman Abo Serih
RGRasha Gomma Gomma
Rasha Gomma Gomma
Ahmed Fikry El-sayedAhmed Fikry El-sayed
Ahmed Fikry El-sayed
MHMaher A. Hammad
Maher A. Hammad
GEGhada M. El-Sayed
Ghada M. El-Sayed
Due to the problems assigned by unregulated and indiscriminate applications of ‎pesticides, adverse effects to human health, different life forms, and ecosystems were ‎evolved. Development of technologies that guarantee their elimination in a safe, efficient, ‎and economical way is important, among these strategies, bioremediation that overcomes ‎the limitations of traditional methods for the disposal of hazardous compounds. An ‎organophosphorus pesticide, Glyphosate (N-phosphono methyl glycine), was the most ‎persistent pesticide in the Al-Jabal Al-Asfar drain water canal. Four bacterial isolates ‎recorded a notable degradation behavior toward glyphosate with various capabilities. The ‎PCR amplification of the 16s rDNA gene was employed to identify these bacterial ‎isolates. They were identified as Bacillus cereus NRC1-PP, Pseudomonas alcaligenes ‎NRC2-Gly, Pseudomonas stutzeri NRC3-8PS, and Bacillus licheniformis NRC4-1BL and ‎deposited at GenBank. Bacillus cereus NRC1-PP, as the highest degrader, biodegraded ‎‎28.96% of glyphosate when injected in minimal salt media after ten days. Enhancement ‎of Glyphosate biodegradation potential for Bacillus cereus NRC1-PP through physical ‎mutagen UV radiation and chemical mutagen Ethyl methane sulfonate (EMS) was ‎implemented. The biodegradation fitness was increased to 2.5-fold in UV-10 bacterial ‎mutant. Protein profiles of Bacillus cereus NRC1-PP and its mutants were investigated ‎by SDS-PAGE. Dendrogram of SDS-PAGE based on unweighted pair group method ‎with arithmetic averages algorithm (UPGMA) divided and categorized into 2 main ‎clusters according to similarity coefficient. The enzymatically- generated degradation ‎products of Glyphosate by GC/MS were detected. The treated samples were presented 12 ‎metabolites were detected in the case of UV-10 treatment; however, only presented 7 ‎metabolites were assigned in the untreated sample (control). These metabolites included ‎amino methyl phosphonic, and new ions such as C2N2O and C3H4O3P. The results of this ‎study indicate that bacterial isolate and their mutants are good candidates for Glyphosate ‎biodegradation in safe and efficient behavior