Browsing by Author "Farag, Mohamed A"

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Application of molecular imprinting approach for alkaloids analysis in food and nutraceuticals: review and perspective
(Springer Netherlands, 2023-10) Emara, Samy; Kamal, Maha; Sallam, Ibrahim E; Serag, Ahmed; Farag, Mohamed A
Alkaloids are major dietary components well known for their pharmacological activities. Herbal matrices require extensive processing due to their high level of complexity in order to isolate their alkaloidal contents. Molecularly imprinted polymers (MIPs) are tailored receptors with a highly specific molecular recognition, which is the most important function of receptors. They can hence be utilized in applications wherein selective binding activities are of significance, such as solid phase extraction (SPE), chromatographic separation and chemical sensors. This review presents on recent applications of MIPs to analyze alkaloids in plants and bio-fluid samples as well as herbal formulations. We discuss the develop- ment of nano-sized MIPs for various applications, particularly in biomimetic sensors for electrochemical detection of various alkaloids. Due to its easier phase separation compared to common MISPEs, magnetic MISPEs were also discussed in order to explore the potential benefits of this approach for further phyto- chemical applications.
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.
A Comparative Metabolomics Approach for Egyptian Mango Fruits Classification Based on UV and UPLC/MS and in Relation to Its Antioxidant Effect
(Multidisciplinary Digital Publishing Institute (MDPI), 2022-07) Farag, Mohamed A; Abdelwareth, Amr; Zayed, Ahmed; Eissa, Tarek F.; Dokalahy, Eric; Frolov, Andrej; Wessjohann, Ludger A
Mango (Mangifera indica L.) is a tropical climacteric fruit that encompasses a myriad of metabolites mediating for its nutritive value, unique taste, flavor, and medicinal uses. Egypt is among the top mango producers worldwide, albeit little characterization has been made toward its fruits’ chemical composition. This study aims to assess metabolites difference via comparative profiling and fingerprinting of Egyptian mango in context to its cultivar (cv.) type and/or growth province. To achieve such goal, hyphenated chromatographic techniques (UPLC/MS) and UV spectroscopy were employed and coupled to multivariate data analysis for Egyptian mango fruits’ classification for the first time. UPLC/MS led to the detection of a total of 47 peaks identified based on their elution times and MS data, belonging to tannins as gallic acid esters, flavonoids, xanthones, phenolic acids and oxylipids. UV/Vis spectra of mango fruits showed similar absorption patterns mostly attributed to the phenolic metabolites, i.e., gallic acid derivatives and phenolic acids showing λmax at ca. 240 and 270 nm. Modeling of both UPLC/MS and UV data sets revealed that cv. effect predominated over geographical origin in fruits segregation. Awees (AS) cv. showed the richest phenolic content and in agreement for its recognition as a premium cv. of mango in Egypt. Results of total phenolic content (TPC) assay revealed that AS was the richest in TPC at 179.1 mg GAE/g extract, while Langara from Ismailia (LI) showed the strongest antioxidant effect at 0.41 mg TE/g extract. Partial least square modeling of UV fingerprint with antioxidant action annotated gallates as potential contributor to antioxidant effect though without identification of exact moieties based on UPLC/MS. The study is considered the first-time investigation of Egyptian mango to aid unravel phytoconstituents responsible for fruits benefits using a metabolomics approach.
Effect of Gut Microbiota Biotransformation on Dietary Tannins and Human Health Implications
(MDPI, 4/29/2021) Sallam, Ibrahim E; Abdelwareth, Amr; Attia, Heba; Aziz, Ramy K; Homsi, Masun Nabhan; von Bergen, MArtin; Farag, Mohamed A
Tannins represent a heterogeneous group of high-molecular-weight polyphenols that are ubiquitous among plant families, especially in cereals, as well as in many fruits and vegetables. Hydrolysable and condensed tannins, in addition to phlorotannins from marine algae, are the main classes of these bioactive compounds. Despite their low bioavailability, tannins have many beneficial pharmacological effects, such as anti-inflammatory, antioxidant, antidiabetic, anticancer, and cardioprotective effects. Microbiota-mediated hydrolysis of tannins produces highly bioaccessible metabolites, which have been extensively studied and account for most of the health effects attributed to tannins. This review article summarises the effect of the human microbiota on the metabolism of different tannin groups and the expected health benefits that may be induced by such mutual interactions. Microbial metabolism of tannins yields highly bioaccessible microbial metabolites that account for most of the systemic effects of tannins. This article also uses explainable artificial intelligence to define the molecular signatures of gut-biotransformed tannin metabolites that are correlated with chemical and biological activity. An understanding of microbiota–tannin interactions, tannin metabolism-related phenotypes (metabotypes) and chemical tannin-metabolites motifs is of great importance for harnessing the biological effects of tannins for drug discovery and other health benefits.
Evaluation of Antioxidant Activity and Biotransformation of Opuntia Ficus Fruit: The Effect of In Vitro and Ex Vivo Gut Microbiota Metabolism
(2022-11) Sallam, Ibrahim E; Rolle-Kampczyk, Ulrike; Schäpe, Stephanie Serena; Zaghloul, Soumaya S; El-Dine, Riham S; Shao, Ping; Bergen, Martin von; Farag, Mohamed A
Opuntia ficus-indica biological effects are attributed to several bioactive metabolites. How- ever, these actions could be altered in vivo by biotransformation reactions mainly via gut microbiota. This study assessed gut microbiota effect on the biotransformation of O. ficus-indica metabolites both in vitro and ex vivo. Two-time aliquots (0.5 and 24 h) from the in vitro assay were harvested post incubation of O. ficus-indica methanol extract with microbial consortium, while untreated and treated samples with fecal bacterial culture from the ex vivo assay were prepared. Metabolites were analyzed using UHPLC-QTOF-MS, with flavonoid glycosides completely hydrolyzed in vitro at 24 h being con- verted to two major metabolites, 3-(4-hydroxyphenyl)propanoic acid and phloroglucinol, concurrent with an increase in the gallic acid level. In case of the ex vivo assay, detected flavonoid glycosides in untreated sample were completely absent from treated counterpart with few flavonoid aglycones and 3-(4-hydroxyphenyl)propanoic acid in parallel to an increase in piscidic acid. In both assays, fatty and organic acids were completely hydrolyzed being used as energy units for bacterial growth. Chemometric tools were employed revealing malic and (iso)citric acids as the main discriminating metabolites in vitro showing an increased abundance at 0.5 h, whereas in ex vivo assay, (iso)citric, aconitic and mesaconic acids showed an increase at untreated sample. Piscidic acid was a significant marker for the ex vivo treated sample. DPPH, ORAC and FRAP assays were further employed to determine whether these changes could be associated with changes in antioxidant activity, and all assays showed a decline in antioxidant potential post biotransformation.
Metabolomics-Based Approach for Coffee Beverage Improvement in the Context of Processing, Brewing Methods, and Quality Attributes
(MDPI, 18/03/2022) Farag, Mohamed A; Zayed, Ahmed; Sallam, Ibrahim E; Abdelwareth, Amr; Wessjohann, Ludger A
Coffee is a worldwide beverage of increasing consumption, owing to its unique flavor and several health benefits. Metabolites of coffee are numerous and could be classified on various bases, of which some are endogenous to coffee seeds, i.e., alkaloids, diterpenes, sugars, and amino acids, while others are generated during coffee processing, for example during roasting and brewing, such as furans, pyrazines, and melanoidins. As a beverage, it provides various distinct flavors, i.e., sourness, bitterness, and an astringent taste attributed to the presence of carboxylic acids, alkaloids, and chlorogenic acids. To resolve such a complex chemical makeup and to relate chemical composition to coffee effects, large-scale metabolomics technologies are being increasingly reported in the literature for proof of coffee quality and efficacy. This review summarizes the applications of various mass spectrometry (MS)- and nuclear magnetic resonance (NMR)-based metabolomics technologies in determining the impact of coffee breeding, origin, roasting, and brewing on coffee chemical composition, and considers this in relation to quality control (QC) determination, for example, by classifying defected and non-defected seeds or detecting the adulteration of raw materials. Resolving the coffee metabolome can aid future attempts to yield coffee seeds of desirable traits and best flavor types.
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.