Browsing by Author "Eissa, Tarek F"

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Aroma‑based discrimination of Egyptian versus Indian guava fruits and in response to probiotics as analyzed via SPME/GC–MS and chemometric tools
(Nature Publishing Group, 2023-12) Kamal, Islam M; Zayed, Ahmed; Eissa, Tarek F; Farag, MohamedA
Guava tree (Psidium guajava L., Myrtaceae) is an economic grown worldwide, particularly in tropical and subtropical regions. Guavas encompass numerous cultivars (cvs.) that were discriminated in previous studies based on leaf morphological features and profile of volatile organic compounds (VOCs). Nevertheless, fruit VOCs have also shown outstanding potential for discrimination of other plant taxa, which has not been utilized in guava. Hence, the current study investigates the various guava cvs. harvested from India and Egypt. A total of 5 samples were analyzed by solid phase microextraction coupled to gas chromatography/mass spectrometry. Results led to the detection of 42 VOCs belonging to aldehydes, alcohols, esters, ketones, aliphatic and aromatic hydrocarbons, in addition to monoterpene and sesquiterpene hydrocarbons. Butylated hydroxytoluene and β-caryophyllene were predominant reaching 77% and 41% in Egyptian and Indian guava, respectively. The impact of probiotic fermentation, i.e., Lactobacillus acidophilus and L. plantarum on aroma profile was not significantly different (p > 0.05). Multivariate data analyses were further applied for samples classification and markers determination, including principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). PCA score plot showed clear segregation of Egyptian from Indian specimens, whereas OPLS-DA revealed that β-caryophyllene was associated with white fruit versus 3-butenyl isothiocyanate and muurolol in red fruit type in the case of Indian guava. The richness of Egyptian guava in butylated hydroxytoluene in addition to the presence of vitamin C may potentiate its antioxidant activity, to be followed in subsequent studies regarding its health effects. © 2023, The Author(s).
Chemometrics-Based Aroma Discrimination of 14 Egyptian Mango Fruits of Different Cultivars and Origins, and Their Response to Probiotics Analyzed via SPME Coupled to GC−MS
(ACS Publications, 2022-01) Farag, Mohamed A; Dokalahy, Erick U; Eissa, Tarek F; Kamal, Islam M; Zayed, Ahmed
The present study investigated the volatile organic compounds (VOCs) in 14 Egyptian mango specimens collected from three different regions and of different cultivars (cvs). VOCs were extracted via solid-phase microextraction, followed by gas chromatography−mass spectrometry analysis. The results obtained for sesquiterpene hydrocarbons’ qualitative abundance were represented by 28 peaks, whereas monoterpene hydrocarbons amounted for the highest levels in most of the mango cvs. Multivariate data analyses were employed for sample classification and identification of markers. Unsupervised principal component analysis revealed that “zebdia” cv from the three origins combined together being enriched in terpinolene. Moreover, supervised orthogonal partial least square-discriminant analysis identified β- terpinene and (Z)-geranylacetone in the premium “awees” cv. The impact of probiotic bacteria on mango juice aroma was further assessed revealing no potential changes in the composition. This study provides the first comprehensive insights into Egyptian mango aroma and reveals that the cv type overcomes the geographical origin in their aroma profile.
Peganum harmala enhanced GLP-1 and restored insulin signaling to alleviate AlCl3-induced Alzheimer-like pathology model
(Springer Nature, 06/08/2021) Saleh, Rofida A; Eissa, Tarek F; Abdallah, Dalaal M; Saad, Muhammed A; El-Abhar, Hanan S
Peganum harmala (P. harmala) is a folk medicinal herb used in the Sinai Peninsula (Egypt) as a remedy for central disorders. The main constituents, harmine and harmaline, have displayed therapeutic efficacy against Alzheimer’s disease (AD); however, the P. harmala potential on sensitizing central insulin to combat AD remains to be clarified. An AD-like rat model was induced by aluminum chloride (AlCl3; 50 mg/kg/day for six consecutive weeks; i.p), whereas a methanolic standardized P. harmala seed extract (187.5 mg/kg; p.o) was given to AD rats starting 2 weeks post AlCl3 exposure. Two additional groups of rats were administered either the vehicle to serve as the normal control or the vehicle + P. harmala seed extract to serve as the P. harmala control group. P. harmala enhanced cognition appraised by Y-maze and Morris water maze tests and improved histopathological structures altered by AlCl3. Additionally, it heightened the hippocampal contents of glucagon-like peptide (GLP)-1 and insulin, but abated insulin receptor substrate-1 phosphorylation at serine 307 (pS307-IRS-1). Besides, P. harmala increased phosphorylated Akt at serine 473 (pS473-Akt) and glucose transporter type (GLUT)4. The extract also curtailed the hippocampal content of beta amyloid (Aβ)42, glycogen synthase (GSK)-3β and phosphorylated tau. It also enhanced Nrf2, while reduced lipid peroxides and replenished glutathione. In conclusion, combating insulin resistance by P. harmala is a novel machinery in attenuating the insidious progression of AD by enhancing both insulin and GLP-1 trajectories in the hippocampus favoring GLUT4 production.
Valorization potential of Egyptian mango kernel waste product as analyzed viaGC/MS metabolites profling from diferent cultivars and geographical origins
(Nature Publishing Group, 2024-01) El‑Shabasy, Rehan M; Eissa, Tarek F; Emam, Yossef; Zayed, Ahmed; Fayek, Nesrin; Farag, Mohamed A
Increasing attention has been given to mango (Mangifera indica) fruits owing to their characteristic taste, and rich nutritional value. Mango kernels are typically discarded as a major waste product in mango industry, though of potential economic value. The present study aims to outline the frst comparison of diferent mango kernel cvs. originated from diferent localities alongside Egypt, e.g., Sharqia, Suez, Ismailia, and Giza. Gas chromatography–mass spectroscopy (GC–MS) post silylation analysis revealed that sugars were the major class being detected at 3.5–290.9 µg/mg, with some kernels originating from Sharqia province being the richest amongst other cvs. In consistency with sugar results, sugar alcohols predominated in Sharqia cvs. at 1.3–38.1 µg/mg represented by ribitol, iditol, pinitol, and myo-inositol. No major variation was observed in the fatty acids profle either based on cv. type or localities, with butyl caprylate as a major component in most cvs. identifed for the frst time in mango. Regarding phenolics, Sedeeq cv. represented the highest level at 18.3 µg/mg and showing distinct variation among cvs. posing phenolics as better classifcation markers than sugars. Multivariate data analyses (MVA) confrmed that the premium cvs “Aweis and Fons” were less enriched in sugars, i.e., fructose, talose, and glucose compared to the other cvs. Moreover, MVA of Zabdeya cv. collected from three localities revealed clear segregation to be chemically distinct. Sharqia originated mango kernels were rich in sugars (e.g., glucose and fructose), whilst sarcosine esters predominated in other origins.