Omaish Alqahtani

Dr. Omaish Alqahtani

Najran University, Collage of Pharmacy, Saudi Arabia
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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14 September 2023 in Metabolites
Verified
Journal Article
Open access
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MOMohamed A. A. Orabi
Mohamed A. A. Orabi
ASO HAMEED HASANASO HAMEED HASAN
ASO HAMEED HASAN
SASameh AbouZid
Sameh AbouZid
Dalia El AmirDalia El Amir
Dalia El Amir
Mona HettaMona Hetta
Mona Hetta
MEMohamed A. El-Shanawany
Mohamed A. El-Shanawany
Dietary fruits and vegetables play a vital role as food and drugs and are the main sources of antioxidant defences against degenerative diseases, such as brain dysfunctions, cardiovascular diseases, immune system deteriorations, and cancers, brought on by oxidative damage. Phyllanthus emblica is a significant herbal remedy used in conventional medicine to recover lost strength and power. In this research, the potential value of Phyllanthus emblica as a food and drug is researched. The total phenolic, total flavonoid, and total tannin contents as well as the nutritional value, vitamin C, vitamin E, and mineral contents of different organs of P. emblica were evaluated. The antioxidant and antimicrobial activities of extracts and fractions of different organs of P. emblica were determined. A total of eleven flavonoids, simple phenolic, tannin-related phenolic, and tannin molecules were isolated from a hydroalcoholic extract of the leaves and fruits. The structures were identified by spectroscopic data and comparison with the literature values as gallic acid (1), naringenin 7-O-(6″-O-galloyl)-β-D-glucopyranoside (2), 3,3′-di-O-methyl ellagic acid-4′-O-β-d-glucopyranoside (3), 1-O-galloyl glycerol (4), 1,6-di-O-galloyl-β-d-glucopyranoside (5), flavogallonic acid bislactone (6), corilagin (7), ethyl gallate (8), urolithin M5 (9), (E)-p-coumaroyl-1-O-β-d-glucopyranoside (10), and 1,2,4,6-tetra-O-galloyl-β-d-glucopyranoside (11). Among them, compounds 3 and 10 are first isolated from the plant. Molecular docking was performed to investigate the comparative interactions between positive controls (galantamine and donepezil) and selected compounds utilizing acetylcholinesterase (4EY7) as a target receptor. Results exhibited the potency of these compounds against the target receptor. In summary, P. emblica has a wealth of minerals, vitamins C and E, and polyphenolic phytochemicals that may work together to treat infectious disease, prevent and/or treat oxidative-damage-related illnesses including Alzheimer’s disease.

17 July 2022 in Molecules
Verified
Journal Article
Open access
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HAHany Attia
Hany Attia
HAHassan A. Albarqi
Hassan A. Albarqi
ISIsmail Guda Said
Ismail Guda Said
OAOmaish Alqahtani
Omaish Alqahtani
MRMohamed A. El Raey
Mohamed A. El Raey
Helicobacter pylori (H. pylori) is a global health threat, and the World Health Organization has included H. pylori among 12 bacterial species that require high priority future strategies for the development of new antibiotics due mainly to its high rates of resistance. Metallic nanoparticles are known for their antimicrobial properties. The FDA (Food and Drug Administration) has approved zinc oxide nanoparticles (ZnONPs) as biocompatible antimicrobials. Green synthesis of ZnONPs was performed based on Oak galls extract (OGE) and was characterized by UV, IR, DLS, TEM, and SEM measurements. In addition, LC-MS/MS was used for the identification of OGE constituents. A checkerboard assay was used to evaluate the activity of synthesized Qi-ZnONPs and OGE against H. pylori, and their synergistic effects with amoxicillin were evaluated. LC-MS/MS analyses identified 20 compounds as major gallic acid conjugates. The ZnONPs had average particle sizes of 5.5 nm (DLS) and 7.99 nm (TEM). Both OGE and Qi-ZnONPs exhibited moderate activity against H. pylori. Amoxicillin and Qi-ZnONPs combinations (1:2 and 1:4 amoxicillin:/Qi-ZnONPs) significantly decreased the MIC90 by two-fold and four-fold, respectively, and FIC values for the combinations were more significant than with OGE alone. OGE is rich in phenolics. The synergism between Qi-ZnONPs and amoxicillin can provide an alternative safe agent of low cost to combat H. Pylori infections.

13 June 2022 in BMC Complementary Medicine and Therapies
Verified
Journal Article
Open access
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MMMater H. Mahnashi
Mater H. Mahnashi
YAYahya S. Alqahtani
Yahya S. Alqahtani
AAAli O. Alqarni
Ali O. Alqarni
BABandar Alyami
Bandar Alyami
OAOmaish Alqahtani
Omaish Alqahtani
ASAbdul Sadiq
Abdul Sadiq
Aim: The study was planned to investigate the phytochemicals, antidiabetic and antioxidant studies of A. consanguineum. Methods: The preliminary studies were performed on crude extract and different solvent fractions. Based on the potency, the chloroform fraction was semi-purified to phyto-fractions CHF-1 – 5. Furthermore, CHF-3 was subjected to isolation of pure compounds using column chromatography. The α-glucosidase, α-amylase and antioxidant assays (DPPH, ABTS, H2O2) were performed on all samples. The in-vivo experiments on compounds 1 and 2 were also performed using oral glucose tolerance test. Docking studies were performed on α-glucosidase and α-amylase targets. Results: Among all fractions, the chloroform fraction exhibited excellent activities profile giving IC50 values of 824, 55, 117, 58 and 85 μg/ml against α-glucosidase, α-amylase, DPPH, ABTS and H2O2 targets respectively. Among the five semi-purified chloroform phyto-fractions (CHF-1-5), CHF-3 was the leading fraction in activities giving IC50 values of 85.54, 61.19 and 26.58 μg/ml against α-glucosidase, α-amylase and DPPH respectively. Based on the overall potency and physical amount of CHF-3, it was subjected to purification to get compounds 1 and 2. The two compounds were also found potent in in-vitro activities. The observed IC50 values for compound 1 were 7.93, 28.01 and 6.19 μg/ml against α-glucosidase, α-amylase and DPPH respectively. Similarly, the compound 2 exhibited IC50 of 14.63, 24.82 and 7.654 μg/ml against α-glucosidase, α-amylase and DPPH respectively. Compounds 1 and 2 were potent in decreasing the blood glucose levels in experimental animals. Compounds 1 and 2 also showed interactions with the respective enzymes with molecular docking. Conclusions: We can conclude that A. Consanguineum is a rich source of natural antidiabetic agents. Bioguided isolation of compound 1 and 2 showed potential inhibitions in all tested in-vitro antidiabetic targets. Further, both the compounds were also able to decrease the blood glucose levels in experimental animals.

30 November 2022 in Molecules
Verified
Journal Article
Open access
PDF file
AAAbdulsalam A. Alqahtani
Abdulsalam A. Alqahtani
MRMohamed A. El Raey
Mohamed A. El Raey
EAEman Abdelsalam
Eman Abdelsalam
AIAmmar M. Ibrahim
Ammar M. Ibrahim
OAOmaish Alqahtani
Omaish Alqahtani
HAHany Attia
Hany Attia
Almost one-third of all infectious diseases are caused by viruses, and these diseases account for nearly 20% of all deaths globally. It is becoming increasingly clear that highly contagious viral infections pose a significant threat to global health and economy around the world. The need for innovative, affordable, and safe antiviral therapies is a must. Zinc oxide nanoparticles are novel materials of low toxicity and low cost and are known for their antiviral activity. The genus Pelargonium was previously reported for its antiviral and antimicrobial activity. In this work, Pelargonium zonale leaf extract chemical profile was studied via high-performance liquid chromatography (HPLC) and was used for the biosynthesis of zinc oxide nanoparticles. Furthermore, the antiviral activity of the combination of P. zonale extract and the biosynthesized nanoparticles of ZnO against the human corona 229E virus was investigated. Results revealed that ZnONPs had been biosynthesized with an average particle size of about 5.5 nm and characterized with UV, FTIR, TEM, XRD, and SEM. The antiviral activity showed significant activity and differences among the tested samples in favor of the combination of P. zonale extract and ZnONPs (ZnONPs/Ex). The lowest IC50, 2.028 µg/mL, and the highest SI, 68.4 of ZnONPs/Ex, assert the highest antiviral activity of the combination against human coronavirus (229E).

15 June 2023 in Journal of Ethnopharmacology
Verified
Journal Article
Closed access
MMMater H. Mahnashi
Mater H. Mahnashi
MAMuhammad Ayaz
Muhammad Ayaz
YAYahya S. Alqahtani
Yahya S. Alqahtani
BABandar Alyami
Bandar Alyami
MSMuhammad Shahid
Muhammad Shahid
ASAbdul Sadiq
Abdul Sadiq

14 December 2022 in Pharmaceuticals
Verified
Journal Article
Open access
PDF file
MOMohamed A. A. Orabi
Mohamed A. A. Orabi
OAOmaish Alqahtani
Omaish Alqahtani
BABandar Alyami
Bandar Alyami
AAAhmed Abdullah Al Awadh
Ahmed Abdullah Al Awadh
EAEl-Shaymaa Abdel-Sattar
El-Shaymaa Abdel-Sattar
MAMohamed E. Abouelela
Mohamed E. Abouelela
Lung cancer and cutaneous leishmaniasis are critical diseases with a relatively higher incidence in developing countries. In this research, the activity of Carissa macrocarpa leaf hydromethanolic extract and its solvent-fractions (n-hexane, EtOAc, n-butanol, and MeOH) against the lung adenocarcinoma cell line (A549) and Leishmania major was investigated. The MeOH fraction exhibited higher cytotoxic activity (IC50 1.57 ± 0.04 μg/mL) than the standard drug, etoposide (IC50 50.8 ± 3.16 μg/mL). The anti-L. major results revealed strong growth inhibitory effects of the EtOAc fraction against L. major promastigotes (IC50 27.52 ± 0.7 μg/mL) and axenic amastigotes (29.33 ± 4.86% growth inhibition at 100 μg/mL), while the butanol fraction exerted moderate activity against promastigotes (IC50 73.17 ± 1.62), as compared with miltefosine against promastigotes (IC50 6.39 ± 0.29 μg/mL) and sodium stibogluconate against axenic amastigotes (IC50 22.45 ± 2.22 μg/mL). A total of 102 compounds were tentatively identified using UPLC-ESI-MS/MS analysis of the total extract and its fractions. The MeOH fraction was found to contain several flavonoids and flavan-3-ol derivatives with known cytotoxic properties, whereas the EtOAc fractions contained triterpene, hydroxycinnamoyl, sterol, and flavanol derivatives with known antileishmanial activity. Molecular docking of various polyphenolics of the MeOH fraction with HDAC6 and PDK3 enzymes demonstrates high binding affinity of the epicatechin 3-O-β-D-glucopyranoside and catechin-7-O-β-D-glucopyranoside toward HDAC6, and procyanidin C2, procyanidin B5 toward PDK3. These results are promising and encourage the pursuit of preclinical research using C. macrocarpa’s MeOH fraction as anti-lung cancer and the EtOAc fraction as an anti-L. major drug candidates.