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Publications

Zhang, H.; Lin, S.; Xie, R.; Zhong, W.; Wang, H.; Farag, M. A.; Hussain, H.; Arroo, R. R.; Chen, X.; Xiao, J.; Thermal degradation of (2R, 3R)-dihydromyricetin in neutral aqueous solution at 100 ℃ Food Chem. 435, 137560, (2024) DOI: 10.1016/j.foodchem.2023.137560

In the field of thermal degradation of flavonoids, current studies mainly focused on flavonols. However, the thermal degradation of dihydroflavonols in aqueous solution has received limited attention compared to flavonols. The single C2-C3 bonds of dihydroflavonols, which differs from the C2-C3 double bond in flavonols, may cause different degradation mechanisms. Dihydromyricetin (DMY) is a typical dihydroflavonol with six hydroxyl groups, and possesses various health effects. We explored the thermal degradation of DMY in neutral aqueous solution (pH 7) at 100 ℃. Ultra-performance liquid chromatography combined with photodiode array and electrospray ionization quadrupole-time-of-flight tandem mass spectrometric detection (UPLC-PDA-ESI-QTOF-MS/MS) provided suitable platform for exploring DMY degradation pathways, and negative ion mode was applied. Thermal treatment led to a decline in DMY level with time, accompanied by the appearance of various degradation products of DMY. Degradation mechanisms of DMY included isomerization, oxidation, hydroxylation, dimerization and ring cleavage. The pyrogallol-type ring B of DMY might be initially oxidized into ortho-quinone, which could further attack another DMY to form dimers. In addition, hydroxylation is likely to occur at C-2, C-3 of DMY or DMY dimers, which then further yields ring-cleavage products via breakage of the O1-C2 bond, C2-C3 bond, or C3-C4 bond. The 3-hydroxy-5-(3,3,5,7-tetrahydroxy-4-oxochroman-2-yl) cyclohexa-3,5-diene-1, 2-dione (m/z 333.0244) and unknown compound m/z 435.0925 were annotated as key intermediates in DMY degradation. Four phenolic acids, including 3,4,5-trihydroxybenzoic acid (m/z 169.0136, RT 1.4 min), 2,4,6-trihydroxyphenylglyoxylic acid (m/z 197.0084, RT 1.7 min), 2-oxo-2-(2,4,6-trihydroxyphenyl) acetaldehyde (m/z 181.0132, RT 2.4 min), and 2,4,6-trihydroxybenzoic acid (m/z 169.0139, RT 2.5 min) were identified as the major end products of DMY degradation. In addition, 5-((3,5dihydroxyphenoxy) methyl)-3-hydroxycyclohexa-3,5-diene-1,2-dione (m/z 261.0399, RT 11.7 min) and unidentified compound with m/z 329.0507 (RT 1.0 min) were also suggested to be end products of DMY degradation. These results provide novel insights on DMY stability and degradation products. Moreover, the heat treatment of DMY aqueous solution was found to gradually reduce the antioxidant activities of DMY, and even destroy the beneficial effect of DMY on the gut microbiota composition.
Printed publications

Noleto‐Dias, C.; Farag, M. A.; Porzel, A.; Tavares, J. F.; Wessjohann, L. A.; A multiplex approach of MS, 1D‐, and 2D‐NMR metabolomics in plant ontogeny: A case study on Clusia minor L. organs (leaf, flower, fruit, and seed) Phytochem. Anal. 1-24, (2023) DOI: 10.1002/pca.3300

Introduction: The genus Clusia L. is mostly recognised for the production of prenylated benzophenones and tocotrienol derivatives.Objectives: The objective of this study was to map metabolome variation within Clusia minor organs at different developmental stages.Material and Methods: In total 15 organs/stages (leaf, flower, fruit, and seed) were analysed by UPLC‐MS and 1H‐ and heteronuclear multiple‐bond correlation (HMBC)‐NMR‐based metabolomics.Results: This work led to the assignment of 46 metabolites, belonging to organic acids(1), sugars(2) phenolic acids(1), flavonoids(3) prenylated xanthones(1) benzophenones(4) and tocotrienols(2). Multivariate data analyses explained the variability and classification of samples, highlighting chemical markers that discriminate each organ/stage. Leaves were found to be rich in 5‐hydroxy‐8‐methyltocotrienol (8.5 μg/mg f.w.), while flowers were abundant in the polyprenylated benzophenone nemorosone with maximum level detected in the fully mature flower bud (43 μg/mg f.w.). Nemorosone and 5‐hydroxy tocotrienoloic acid were isolated from FL6 for full structural characterisation. This is the first report of the NMR assignments of 5‐hydroxy tocotrienoloic acid, and its maximum level was detected in the mature fruit at 50 μg/mg f.w. Seeds as typical storage organ were rich in sugars and omega‐6 fatty acids.Conclusion: To the best of our knowledge, this is the first report on a comparative 1D‐/2D‐NMR approach to assess compositional differences in ontogeny studies compared with LC‐MS exemplified by Clusia organs. Results derived from this study provide better understanding of the stages at which maximal production of natural compounds occur and elucidate in which developmental stages the enzymes responsible for the production of such metabolites are preferentially expressed.
Printed publications

Nagia, M.; Morgan, I.; Gamel, M. A.; Farag, M. A.; Maximizing the value of indole-3-carbinol, from its distribution in dietary sources, health effects, metabolism, extraction, and analysis in food and biofluids Crit. Rev. Food Sci. Nutr. 1-22, (2023) DOI: 10.1080/10408398.2023.2197065

Indole-3-carbinol (I3C) is a major dietary component produced in Brassica vegetables from glucosinolates (GLS) upon herbivores’ attack. The compound is gaining increasing interest due to its anticancer activity. However, reports about improving its level in plants or other sources are still rare. Unfortunately, I3C is unstable in acidic media and tends to polymerize rendering its extraction and detection challenging. This review presents a multifaceted overview of I3C regarding its natural occurrence, biosynthesis, isolation, and extraction procedure from dietary sources, and optimization for the best recovery yield. Further, an overview is presented on its metabolism and biotransformation inside the body to account for its health benefits and factors to ensure the best metabolic yield. Compile of the different analytical approaches for I3C analysis in dietary sources is presented for the first time, together with approaches for its detection and its metabolism in body fluids for proof of efficacy. Lastly, the chemopreventive effects of I3C and the underlying action mechanisms are summarized. Optimizing the yield and methods for the detection of I3C will assist for its incorporation as a nutraceutical or adjuvant in cancer treatment programs. Highlighting the complete biosynthetic pathway and factors involved in I3C production will aid for its future biotechnological production.
Publications

S. Ramadan, N.; Fayek, N. M.; M. El-Sayed, M.; S. Mohamed, R.; Wessjohann, L. A.; Farag, M. A.; Averrhoa carambola L. fruit and stem metabolites profiling and immunostimulatory action mechanisms against cyclosporine induced toxic effects in rat model as analyzed using UHPLC/MS-MS-based chemometrics and bioassays Food Chem. Toxicol. 179, 114001, (2023) DOI: 10.1016/j.fct.2023.114001

The Averrhoa carambola L. tree encompasses a myriad of phytochemicals contributing to its nutritional and health benefits. The current study aims at investigating the A. carambola L. the metabolite profile grown in tropical and temperate regions represented by fruit and stem, for the first time using UPLC/MS-based molecular networking and chemometrics. Asides, assessment of the immunostimulatory effect of ripe fruit and stem, was compared in relation to metabolite fingerprints. Eighty metabolites were identified, 8 of which are first-time to be reported including 3 dihydrochalcone-C-glycosides, 4 flavonoids, and one phenolic. Multivariate data analysis revealed dihydrochalcones as origin-discriminating metabolites between temperate and tropical grown fruits. Further, an in vivo immunomodulatory assay in a cyclosporine A-induced rat model revealed a potential immune-enhancing effect as manifested by down-regulation of inflammatory markers (IL-6, INF-γ, IL-1, TLR4, and ESR) concurrent with the up-regulation of CD4 level and the CD4/CD8 ratio. Moreover, both extracts suppressed elevation of liver and kidney functions in serum as well as reduction in oxidative stress with concurrent increased levels of T-protein, albumin, globulin, and A/G ratio. This study pinpoints differences in secondary metabolite profiles amongst A. carambola L. accessions from different origins and organ type and its immunomodulatory action mechanisms.
Publications

Farag, M. A.; Baky, M. H.; Morgan, I.; Khalifa, M. R.; Rennert, R.; Mohamed, O. G.; El-Sayed, M. M.; Porzel, A.; Wessjohann, L. A.; Ramadan, N. S.; Comparison of Balanites aegyptiaca parts: metabolome providing insights into plant health benefits and valorization purposes as analyzed using multiplex GC-MS, LC-MS, NMR-based metabolomics, and molecular networking RSC Adv. 13, 21471-21493, (2023) DOI: 10.1039/d3ra03141a

Balanites aegyptiaca (L.) Delile (Zygophyllaceae), also known as the desert date, is an edible fruit-producing tree popular for its nutritional and several health benefits. In this study, multi-targeted comparative metabolic profiling and fingerprinting approaches were conducted for the assessment of the nutrient primary and secondary metabolite heterogeneity in different parts, such as leaves, stems, seeds, unripe, and ripe fruits of B. aegyptiaca using nuclear magnetic resonance (NMR), ultra-performance liquid chromatography (UPLC-MS), and gas chromatography mass-spectrometry (GC-MS) based metabolomics coupled to multivariate analyses and in relation to its cytotoxic activities. NMR-based metabolomic study identified and quantified 15 major primary and secondary metabolites belonging to alkaloids, saponins, flavonoids, sugars, and amino and fatty acids. Principal component analysis (PCA) of the NMR dataset revealed α-glucose, sucrose, and isorhamnetin as markers for fruit and stem and unsaturated fatty acids for predominated seeds. Orthogonal projections to latent structure discriminant analysis (OPLS-DA) revealed trigonelline as a major distinctive metabolite in the immature fruit and isorhamnetin as a major distinct marker in the mature fruit. UPLC-MS/MS analysis using feature-based molecular networks revealed diverse chemical classes viz. steroidal saponins, N-containing metabolites, phenolics, fatty acids, and lipids as the constitutive metabolome in Balanites. Gas chromatography-mass spectroscopy (GC-MS) profiling of primary metabolites led to the detection of 135 peaks belonging to sugars, fatty acids/esters, amino acids, nitrogenous, and organic acids. Monosaccharides were detected at much higher levels in ripe fruit and disaccharides in predominate unripe fruits, whereas B. aegyptiaca vegetative parts (leaves and stem) were rich in amino acids and fatty acids. The antidiabetic compounds, viz, nicotinic acid, and trigonelline, were detected in all parts especially unripe fruit in addition to the sugar alcohol D-pinitol for the first time providing novel evidence for B. aegyptiaca use in diabetes. In vitro cytotoxic activity revealed the potential efficacy of immature fruit and seeds as cytotoxic agents against human prostate cancer (PC3) and human colorectal cancer (HCT-116) cell lines. Collectively, such detailed profiling of parts provides novel evidence for B. aegyptiaca medicinal uses.
Publications

Abdel Shakour, Z. T.; El-Akad, R. H.; Elshamy, A. I.; El Gendy, A. E.-N. G.; Wessjohann, L. A.; Farag, M. A.; Dissection of Moringa oleifera leaf metabolome in context of its different extracts, origin and in relationship to its biological effects as analysed using molecular networking and chemometrics Food Chem. 399, 133948, (2023) DOI: 10.1016/j.foodchem.2022.133948

M. oleifera known as “miracle tree” is increasingly used in nutraceuticals for the reported health effects and nutritional value of its leaves. This study presents the first metabolome profiling of M. oleifera leaves of African origin using different solvent polarities via HR-UPLC/MS based molecular networking followed by multivariate data analyses for samples classification. 119 Chemicals were characterized in both positive and negative modes belonging to 8 classes viz. phenolic acids, flavonoids, peptides, fatty acids/amides, sulfolipids, glucosinolates and carotenoids. New metabolites i.e., polyphenolics, fatty acids, in addition to a new class of sulfolipids were annotated for the first time in Moringa leaves. In vitro anti-inflammatory and anti-aging bioassays of the leaf extracts were assessed and in correlation to their metabolite profile via multivariate data analyses. Kaempferol, quercetin and apigenin-O/C-glycosides, fatty acyl amides and carotenoids appeared crucial for biological activities and leaves origin discrimination.
Publications

Otify, A. M.; Ibrahim, R. M.; Abib, B.; Laub, A.; Wessjohann, L. A.; Jiang, Y.; Farag, M. A.; Unveiling metabolome heterogeneity and new chemicals in 7 tomato varieties via multiplex approach of UHPLC-MS/MS, GC–MS, and UV–Vis in relation to antioxidant effects as analyzed using molecular networking and chemometrics Food Chem. 417, 135866, (2023) DOI: 10.1016/j.foodchem.2023.135866

Tomatoes show diverse phytochemical attributes that contribute to their nutritive and health values. This study comprehensively dissects primary and secondary metabolite profiles of seven tomato varieties. UHPLC-qTOF-MS assisted molecular networking was used to monitor 206 metabolites, 30 of which were first-time to be reported. Flavonoids, as valuable antioxidants, were enriched in light-colored tomatoes (golden sweet, sun gold, and yellow plum) versus high tomatoside A, an antihyperglycemic saponin, in cherry bomb and red plum varieties. UV–Vis analysis revealed similar results with a strong absorbance corresponding to rich phenolic content in light varieties. GC–MS unveiled monosaccharides as the main contributors to samples’ segregation, found abundant in San Marzano tomato accounting for its sweet flavor. Fruits also demonstrated potential antioxidant activities in correlation to their flavonoids and phospholipids. This work provides a complete map of tomatoes’ metabolome heterogeneity for future breeding programs and a comparative approach utilizing different metabolomic platforms for tomato analysis.
Publications

Noleto-Dias, C.; Picoli, E. A. T.; Porzel, A.; Wessjohann, L. A.; Tavares, J. F.; Farag, M. A.; Metabolomics characterizes early metabolic changes and markers of tolerant Eucalyptus ssp. clones against drought stress Phytochemistry 212, 113715, (2023) DOI: 10.1016/j.phytochem.2023.113715

L’Hér. (Myrtaceae) is one of the economically most important and widely cultivated trees for wood crop purposes worldwide. Climatic changes together with the constant need to expand plantations to areas that do not always provide optimal conditions for plant growth highlight the need to assess the impact of abiotic stresses on eucalypt trees. We aimed to unveil the drought effect on the leaf metabolome of commercial clones with differential phenotypic response to this stress. For this, seedlings of 13 clones were grown at well-watered (WW) and water-deficit (WD) conditions and their leaf extracts were subjected to comparative analysis using ultra-high performance liquid chromatography coupled to mass spectrometry (UPLC-MS) and nuclear magnetic resonance spectroscopy (NMR). UPLC-MS and NMR analyses led to the annotation of over 100 molecular features of classes such as cyclitols, phenolics, flavonoids, formylated phloroglucinol compounds (FPCs) and fatty acids. Multivariate data analysis was employed for specimens\' classifications and markers identification from both platforms. The results obtained in this work allowed us to classify clones differing in drought tolerance. Classification models were validated using an extra subset of samples. Tolerant plants exposed to water deficit accumulated arginine, gallic acid derivatives, caffeic acid and tannins at higher levels. In contrast, stressed drought-sensitive clones were characterised by a significant reduction in glucose, inositol and shikimic acid levels. These changes in contrasting drought response eucalypt pave ways for differential outcomes of tolerant and susceptible phenotypes. Under optimal growth conditions, all clones were rich in FPCs. These results can be used for early screening of tolerant clones and to improve our understanding of the role of these biomarkers in Eucalyptus tolerance to drought stress.
Publications

Shakour, Z. T.; Shehab, N. G.; Gomaa, A. S.; Wessjohann, L. A.; Farag, M. A.; Metabolic and biotransformation effects on dietary glucosinolates, their bioavailability, catabolism and biological effects in different organisms Biotechnol. Adv. 54, 107784, (2022) DOI: 10.1016/j.biotechadv.2021.107784

Glucosinolate-producing plants have long been recognized for both their distinctive benefits to human nutrition and their resistance traits against pathogens and herbivores. Despite the accumulation of glucosinolates (GLS) in plants is associated with their resistance to various biotic and abiotic stresses, the defensive and biological activities of GLS are commonly conveyed by their metabolic products. In view of this, metabolism is considered the driving factor upon the interactions of GLS-producing plants with other organisms, also influenced by plant and plant attacking or digesting organism characteristics. Several microbial pathogens and insects have evolved the capacity to detoxify GLS-hydrolysis products or inhibit their formation via different means, highlighting the relevance of their metabolic abilities for the plants\' defense system activation and target organism detoxification. Strikingly, some bacteria, fungi and insects can likewise produce their own myrosinase (MYR)-like enzymes in one of the most important adaptation strategies against the GLS-MYR plant defense system. Knowledge of GLS metabolic pathways in herbivores and pathogens can impact plant protection efforts and may be harnessed upon for genetically modified plants that are more resistant to predators. In humans, the interest in the implementation of GLS in diets for the prevention of chronic diseases has grown substantially. However, the efficiency of such approaches is dependent on GLS bioavailability and metabolism, which largely involves the human gut microbiome.Among GLS-hydrolytic products, isothiocyanates (ITC) have shown exceptional properties as chemical plant defense agents against herbivores and pathogens, along with their health-promoting benefits in humans, at least if consumed in reasonable amounts. Deciphering GLS metabolic pathways provides critical information for catalyzing all types of GLS towards the generation of ITCs as the biologically most active metabolites. This review provides an overview on contrasting metabolic pathways in plants, bacteria, fungi, insects and humans towards GLS activation or detoxification. Further, suggestions for the preparation of GLS containing plants with improved health benefits are presented.
Publications

Otify, A. M.; Serag, A.; Porzel, A.; Wessjohann, L. A.; Farag, M. A.; NMR metabolome-based classification of Cymbopogon Species: a prospect for phyto-equivalency of its different accessions using chemometric tools Food Analytical Methods 15, 2095-2106, (2022) DOI: 10.1007/s12161-022-02257-8

Cymbopogon species are widely distributed worldwide and known for their high essential oil content with potential commercial and medicinal benefits justifying for their inclusion in food and cosmetics. Most species received scant characterization regarding their full complement of bioactive constituents necessary to explain their medicinal activities. In this study, the metabolite profiles of 5 Cymbopogon species, C. citratus, C. flexuosus, C. procerus, C. martini, and C. nardus, were characterized via NMR-based metabolomics. The results of 13 shoot accessions revealed the identification and quantification of 23 primary and secondary metabolites belonging to various compound classes. Multivariate analyses were used for species classification, though found not successful in discrimination based on geographical origin. Nevertheless, C. citratus was found particularly enriched in neral, geranial, (E)-aconitic acid, isoorientin, and caffeic acid as the major characterizing metabolites compared to other species, while an unknown apigenin derivative appeared to discriminate C. martini. The high essential oil and phenolic content in C. citratus emphasizes its strong antioxidant activity, whereas (E)-aconitic acid accounts for its traditional use as insecticide. This study affords the first insight into metabolite compositional differences among Cymbopogon species. Moreover, antimicrobial, insecticidal, antidiabetic, and antioxidant compounds were identified that can be utilized as biomarkers for species authentication.
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