|Year : 2020 | Volume
| Issue : 71 | Page : 592-599
Profiling of antiviral and antioxidant phytochemicals of Pterocephalus frutescens hochist. using high-resolution ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometer
Atef A El-Hela1, Mostafa M Hegazy1, Marwa S Abu Bakr2, Hatem S Abbass3
1 Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University (Boys), Cairo 11884, Egypt
2 Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University (Girls), Cairo 11884, Egypt
3 Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University (Boys), Cairo 11884; Department of Pharmacognosy, Faculty of Pharmacy, Sinai University, Kantara 41636, Egypt
|Date of Submission||15-Dec-2019|
|Date of Decision||05-Feb-2020|
|Date of Acceptance||16-Apr-2020|
|Date of Web Publication||20-Oct-2020|
Hatem S Abbass
Department of Pharmacognosy, Faculty of Pharmacy, Sinai University, Kantara
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: Medicinal plant extracts and herbal preparations are complex mixtures of active and ballast substances, which may contain in frequently up to several hundreds of different constituents, with no exactly defined structures at which chromatography undoubtedly is a fundamental tool to overcome the challenges of these phytoanalytics. Aim of the Study: To investigate Pterocephalus frutescens aerial part extracts biologically and chemically and the correlation of biologically active constituents with their corresponding activities. Materials and Methods: Ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometer with principal component statistical analysis was used for the identification of phytoconstituents, while spectrophotometer was used for quantitative analysis and both qualitative and quantitative antioxidant effects using stable radical diphenylpicrylhydrazyl, and the cytopathic effect inhibition assay was used for antiviral screening. Results and Conclusion: P. frutescens extracts exhibited antioxidant and antiviral activities along with tentative identifying of 46 compounds from which 38 compounds were correlated with either antiviral and/or antioxidant activities, besides the quantification of phenolic, flavonoid, phenylethanoid, and iridoid contents.
Keywords: Antioxidant, antiviral, mass spectrometry, principal component analysis, ultra-performance liquid chromatography
|How to cite this article:|
El-Hela AA, Hegazy MM, Abu Bakr MS, Abbass HS. Profiling of antiviral and antioxidant phytochemicals of Pterocephalus frutescens hochist. using high-resolution ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometer. Phcog Mag 2020;16:592-9
|How to cite this URL:|
El-Hela AA, Hegazy MM, Abu Bakr MS, Abbass HS. Profiling of antiviral and antioxidant phytochemicals of Pterocephalus frutescens hochist. using high-resolution ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometer. Phcog Mag [serial online] 2020 [cited 2020 Dec 5];16:592-9. Available from: http://www.phcog.com/text.asp?2020/16/71/592/298702
- Biological investigation of Pterocephalus frutescens growing in Yemen showed both antiviral and antioxidant activities at which the responsible secondary metabolites for these activities were identified using rapid and accurate chromatographic analysis method as well. Quantification of the most important chemical classes was done for further confirmation and explaining of these activities.
Abbreviations used: BHT: Butylated hydroxy toluene; DPPH: Diphenylpicrylhydrazyl; ESI: Electrospray ionization; IC50value: Inhibition concentration of sample at 50% fall in absorbance; HAV: Hepatitis virus type A; HSV-I: Herpes simplex virus type I; HSV-II: Herpes simplex virus type II; PCA: Principal component analysis; RCMB: Regional Center for Mycology and Biotechnology; RT: Retention time; UPLC/QTOF-MS/MS: Ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometer.
| Introduction|| |
Quadrupole time-of-flight mass spectrometer attached to ultra-performance liquid chromatography (UPLC/QTOF-MS/MS) is nearly standard equipment in a modern analytical laboratory and is indispensable for scientific research on a high level as screening and identifying compounds in different medicinal plants in a fast and accurate manner. The honeysuckle family or Caprifoliaceae (Dipsacaceae) family is consisting of about 860 species and 42 genera, which distributed in Europe, Asia, and Africa. Some species of this family have been naturalized in other places.Pterocephalus, comprising 25 species, ranges from the Mediterranean, to Central Asia, the Himalayas, Western China, and tropical Africa. Plants of the genus Pterocephalus are widely used in folkloric medicines, around the entire world, as anti-inflammatory, analgesic, antihepatotoxic, antioxidant, antibacterial, spasmolytic, hemostatic, and astringent properties.,,, Several active constituents have been isolated from genus Pterocephalus including iridoid, hydroxycinnamic acid esters, phenolic glycosides, lignans, triterpenoid saponins, and flavonoid C-glycosides.,,, Surprisingly, Pterocephalus frutescens was not evaluated phytochemically and/or biologically, up to this date. In the present work, it is worthy to give an idea about the evaluation of antiviral and antioxidant activities and illustrating secondary metabolites responsible for both activities using reliable, fast, accurate, simple, and reproducible technique UPLC/QTOF-MS/MS in association with principal component analysis (PCA) as a qualitative technique. Quantitative measurements of polyphenolic content are of interest as a lot of findings have been reported earlier, suggesting a relationship between total polyphenols content and health effects, mainly antioxidant activity which tested in our work.
| Materials and Methods|| |
The aerial parts of P. frutescens Hochist. were collected in June 2017 at flowering stage from Jabal An-Nabi Shu'ahyb, Sanaa, Al Yemen. The plant was collected, identified, and authenticated by Dr. Abdo H. Marey, Professor of Botany and Plant Taxonomy, Faculty of Science, Al-Azhar University, Cairo, Egypt. A voucher sample was kept in the Herbarium of Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt.
Extraction and isolation
Air-dried powdered aerial part plant material of P. frutescens (250 g) was extracted by Soxhlet apparatus with n-hexane (2 × 2 L) and then with methanol (3 × 3 L) to afford (7.5 and 35 g), respectively, after evaporation under vacuum by a rotatory evaporator (BUCHI Rotavapor® R-210/R-215, Germany). From methanol extract, 0.5 g was subjected to the quantitative determination of polyphenolics and UPLC/QTOF-MS/MS analysis; 1 g reserved for biological investigations and the remaining residue were dissolved in water and then partitioned successively with ethyl acetate (2 × 200 mL) and n-butanol saturated with water (3 × 200 mL) to afford light brown masses (8.5 and 11 g), respectively.
Quantitative determination of polyphenolics
Quantitative determination of phenolic, flavonoid, phenylethanoid, and iridoid contents using selective method for each phytochemical class was done using Genesys Spectrophotometer (Milton Roy, INC., Rochester, NY, USA). The reagents used for each were Folin-Ciocalteu (Sigma Chemical Co., St. Louis, MO, USA) and gallic acid (Merck, Darmstadt, Germany) for phenolic content quantification; quercetin (Merck Co. Darmstadt, Germany) and aluminum chloride (Merck, Darmstadt, Germany) for flavonoid content quantification, Arnow's reagent and verbascoside (Sigma Chemical Co., St. Louis, MO, USA) for phenylethanoid content quantification; and Trim and Hill reagent and Herbagoside (Sigma Chemical Co., St. Louis, MO, USA) for iridoid content quantification.
Screening of antiviral activity was achieved using cytopathic effect (CPE) inhibition assay against hepatitis virus type A (HAV) and herpes simplex virus type I (HSV-I) and II (HSV-II) at the Regional Center for Mycology and Biotechnology, Al-Azhar University. Incubation was done at 37°C for 5 days and observation was made every 24 h to record the CPE. Antiviral activity was determined by the inhibition of CPE compared with control. The results were expressed as:
–ve: No inhibition, +: 25% inhibition, ++: 50 inhibition, +++: 75% inhibition, and ++++: 100% inhibition of CPE.
Determination of the antioxidant effect of the different extracts of P. frutescens was done using stable radical diphenylpicrylhydrazyl (DPPH) (Sigma Chemical Co., St. Louis, MO, USA). Both qualitative and quantitative antioxidant effects were experimented.
TLC assay (qualitative method)
20 μL aliquot of each extract was spotted on silica gel plates and developed using butanol:acetic acid:water (4:1:5) as a mobile phase; after development, the dried TLC plates were sprayed with 0.2% DPPH solution (Sigma Chemical Co., St. Louis, MO, USA) in methanol and examined after 30 min, where active extracts as antioxidants appeared as yellow spots against purple background.
Spectrophotometric assay (quantitative method)
The test was carried out by adding 160 μL (0.1 mM) DPPH solution in methanol to 40 μL of each sample solution in methanol. After 30 min, the absorbance was measured at 517 nm. Lower absorbance of the reaction mixture indicates higher free radical scavenging activity according to recent published method. Butylated hydroxy toluene (BHT) (Sigma Chemical Co., St. Louis, MO, USA) in methanol was used as standard. The capability of scavenging the DPPH radical was calculated using the following equation:
DPPH scavenging effect (%) = [(Acontrol− Asample)/Acontrol] – 100.
The the inhibition concentration of sample at 50% fall in absorbance of DPPH (IC50) value was used to compare the DPPH scavenging activity of the highest free radical scavenging activity extract with two standard controls, BHT and quercetin using various concentrations in methanol according to previously discussed method.
Ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometer analysis
The lyophilized plant extracted sample injected in the positive mode at which separation of small molecules was carried out on a Axion AC system (Kyoto, Japan) connected with an auto sampler system, an In-Line filter disks precolumn (0.5 μm × 3.0 mm, Phenomenex, USA), and a Xbridge C18(3.5 μm, 2.1 mm × 50 mm) column (Waters Corporation, Milford, MA, USA) maintained at 40°C and a flow rate of 300 μL/min. The mobile phase composition and the gradient elution were performed according to the method discussed in Fayek et al. LC-MS grade acetonitrile and gradient solvents including isopropanol, methanol, dichloromethane, and ethyl acetate were provided by Thermo-Fisher (Thermo Fisher Scientific, USA). Formic acid 98%, ammonium hydroxide, ammonium formate, and ammonium acetate were purchased from Sigma-Aldrich (Sigma-Aldrich Co., Louis St., MO, USA). MS was performed on a TripleTOF™ 5600 System QTOF/MS with a Duo-Spray™ source operating in the electrospray ionization mode (AB SCIEX, Concord, Canada). The sprayer capillary and declustering potential voltages were 4500 and 80 V. The source temperature, collision energy, ion tolerance, and Triple TOF 5600 operation parameters were reported in Fayek et al. The method consisted of high-resolution survey spectra from 50 to 1100 m/z, and the mass spectrometer was operated in a pattern where a 50-ms survey scan was detected. Subsequently, the top 15 intense ions were selected for acquiring MS/MS fragmentation spectra after each scan.
Data were processed using MS-DIAL 3.96 software for nontargeting small molecule comprehensive analysis of the sample. According to the acquisition mode, ReSpect Positive (2737 records), MassBank Positive (8068 records), and GNPS Positive (8782 records) databases were used as reference databases. The search parameters were set according to Tsugawa et al. The MS-DIAL output was used to make manual annotation and confirmation of the identified peaks using PCA, which is an unsupervised clustering method requiring little prior knowledge of the data set. PCA scores' plot analysis was performed in Excel using a macro written by Tsugawa et al. and is available for free.
| Results and Discussion|| |
Quantitative determination of polyphenolics
The results of this study provide evidence that the methanol extract has phenolic, flavonoid, phenylethanoid, and iridoid compounds in relatively high amounts [Table 1]; therefore, this species may have a great relevance in the prevention and therapies of diseases in which oxidants or free radicals are implicated.
|Table 1: Quantitative determination of total phenolic, flavonoid, phenylethanoid, and iridoid contents of the methanol extract of Pterocephalus frutescens|
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The results of antiviral screening of different extracts of P. frutescens [Table 2] showed that the observed activity of both hexane and ethyl acetate extracts on (HAV, HSV-I, and HSV-II) was attributed to flavonoids identified in the plant extract by UPLC/QTOF-MS/MS, due to inhibitory structure–function relationship between flavonoids and various enzymes associated with the life cycle of viruses. The chromatographic UPLC/QTOF-MS/MS method revealed the presence of 30 compounds with antiviral potentials which were reported previously as shown in [Table 6]. For example, amentoflavone has activity against HSV-I and HSV-II with EC50 values of 17.9 and 48.0 mg/ml, respectively, as well apigenin which reported to have the highest inhibition against HSV-I with the widest therapeutic range (0.4–1.6 μg/mL) and loliolide which has both anti-HSV and anti-hepatitis virus type C (HCV).,, Phenolic and iridoid compounds also play an important role as antiviral agents; the presence of 98 mg% of phenolic compounds along with 40 μg% of iridoid compounds explains both hexane and ethyl acetate antiviral activities.
|Table 2: Antiviral screening of different extracts of Pterocephalus frutescens|
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Qualitative TLC-DPPH assay of the tested extracts showed that they are active as DPPH scavengers appearing as zones with different Rf values in the chromatogram; then, quantitative estimation of their antioxidant potentials at dose level of 0.1 mg/ml revealed that they possess significant DPPH free radical scavenging activity which is proven comparable to the reference synthetic antioxidant (BHT). This activity may be explained by high polyphenolic compound contents [Table 1] and further confirmed by tentatively identification of 38 antioxidant compounds [Table 6], which are distributed in different plant extracts. For example, flavonoid aglycons (apigenin, kaempferol, and quercetin) concentrated in hexane extract; flavonoid glycosides and other phenolic compounds concentrated in both ethyl acetate and n-butanol extracts. The most promising extract was ethyl acetate with 89.93% DPPH scavenging activity [Table 3] and an IC50 of 0.05 mg/mL nearly similar to that of BHT [Table 4].
|Table 3: Calculated percent free radical scavenging activity of the different extracts of Pterocephalus frutescens and butylated hydroxy toluene|
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|Table 4: Diphenylpicrylhydrazyl free radical scavenging activity IC50 (mg/ml) of Pterocephalus frutescens ethyl acetate extract, butylated hydroxy toluene, and quercetin|
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Interpretation of ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometer results
A total of 46 compounds were tentatively identified in [Table 5]; whereas the data were obtained from PCA scores' plot analysis from MS-DIAL exhibited a pseudomolecular ion peaks with different adducts. The compounds include amino acids (3), coumarins (4), simple phenolic compounds (9), and flavonoids of different subclasses (23) and of other different chemical classes (7) [Table 6].
|Table 5: Metabolites identified from methanol extract of Pterocephalus frutescens using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometer analysis in positive ionization mode|
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|Table 6: The suspected biological active metabolites and their chemical class|
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Compound identification based on the data of MS-DIAL includes assigning of the compounds with the highest total score above 70%, dissociating the link between precursors and their fragment ions, compromising the molecular identification process, and expressing the fragment presence by %. These two criteria were achieved by DIA methods; reducing false-negative results in contrast to traditional data-dependent MS/MS acquisitions. The further confirmation of the compounds was done by comparison with METLIN (http://metlin.scripps.edu), a freely accessible web-based. In addition to traditional methods of confirmation utilizing retention time, comparison of fragmentation pattern of each chemical class with literature reviews and high-resolution mass error values calculations using the following formula:
Error = (Experimental mass − Calculated mass)/Experimental mass.
To improve mass accuracy, no error exceeds 14 ppm. For comparison with literatures of amino acids, the characteristic m/z was due to the loss of 18 and 46 amu appears to be prevalent so that the [(M + H)-H2O]+ and [(M + H)-CO2H2]+, respectively. The losses of hydroxyl, methyl, or carboxylic groups were helpful in the identification of the specific phenolic compounds to form fragments at m/z [M + H-16]+, [M + H-14]+, or [M + H-44]+, respectively. Coumarin derivatives common fragment ions attributed to loss of CO from the pyrone ring to form a benzofuran ring at m/z [M + H-28]+ which is further fragmented by the loss of H2O moiety to form a fragment at m/z [M + H-18]+. Another fragment ions have been attributed to generate a ketene ion at m/z [M + H-72]+. The hydroxy-substituted coumarins showed fragmentation process with the loss of C2H2O to generate a signal at m/z [M + H-42]+. The fragmentation patterns of flavonoids were very diverse according to subclass (flavones, flavonols, flavanones, and/or isoflavones) and according to glycosylation pattern which previously published in details.,,
| Conclusion|| |
Our results showed that P. frutescens has a high interesting value for pharmaceutical industries as it revealed antiviral and antioxidant activities. Tentative profiling of different secondary metabolites of P. frutescens aerial parts was done in a fast and accurate manner without tedious routine experiments, which could be applicable for chemical investigation of different plant materials.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Steinmann D, Ganzera M. Recent advances on HPLC/MS in medicinal plant analysis. J Pharm Biomed Anal 2011;55:744-57.
Kletter C, Kriechbaum M. Tibetan Medicinal Plants. CRC Press; 2001.
Fahem A, Ahmed A, Maha M, Soltan A, Hussein A, Zaki A. Anti-hepatotoxic effect of Pterocephalus sanctus
growing in Egypt. JASRM 2008;3:83-7.
Wu CL, Zhang ZF, Liu Y. A systematic review on Dipsacaceae
species research development. J Chengdu Med Coll 2009;1.
Guo C, Wu Y, Zhu Y, Wang Y, Tian L, Lu Y, et al
and In vivo
antitumor effects of n-butanol extracts of Pterocephalus hookeri
on hep3b cancer cell. Evid Based Complement Alternat Med 2015;2015:159132.
Vahedi H, Nasrabadi M, Lari J, Halimi M. Volatile constituents and antimicrobial activities of Pterocephalus canus
. J Med Plants Res 2011;5:5646-8.
Wu YC, Guo CX, Zhu YZ, Li YM, Guo FJ, Zhu GF. Four new bis-iridoids isolated from the traditional Tibetan herb Pterocephalus hookeri
. Fitoterapia 2014;98:104-9.
Ahmed FA, Shahat AA. Flavonoid C-glycosides from Pterocephalus sanctus
growing in Egypt. Natl Product Communications 2006;1:1934578X0600100605.
Gülcemal D, Masullo M, Alankuş-Calişkan O, Karayildirim T, Senol SG, Piacente S, et al
. Monoterpenoid glucoindole alkaloids and iridoids from Pterocephalus pinardii
. Magn Reson Chem 2010;48:239-43.
Gülcemal D, Bedir E, Karayıldırım T, Milena M, Piacente S, Şenol S, et al
. Constituents of Pterocephalus pinardii
Boiss. Planta Med 2009;75:PJ103.
Yang CS, Sang S, Lambert JD, Lee MJ. Bioavailability issues in studying the health effects of plant polyphenolic compounds. Mol Nutr Food Res 2008;52 Suppl 1:S139-51.
Abdelhady NM, Badr KA. Comparative study of phenolic content, antioxidant potentials and cytotoxic activity of the crude and green synthesized silver nanoparticles' extracts of two Phlomis
species growing in Egypt. J Pharmacog Phytochem 2016;5:377-83.
Vijayan P, Raghu C, Ashok G, Dhanaraj SA, Suresh B. Antiviral activity of medicinal plants of Nilgiris. Indian J Med Res 2004;120:24-9.
El-Hela AA, Abdelhady NM, Gonaid MH, Badr KA. Antioxidant, cytotoxic and antimicrobial activities of crude and green synthesized silver nanoparticles' extracts of Crataegus sinaica
Boiss leaves. Int J Pharm Sci Rev Res 2017;45:223-32.
Yılmaz H, Çarıkçı S, Kılıç T, Dirmenci T, Arabacı T, Gören AC. Screening of chemical composition, antioxidant and anticholinesterase activity of section Brevifilamentum of Origanum
(L.) species. Records Natl Products 2017;11.
Fayek NM, Farag MA, Abdel Monem AR, Moussa MY, Abd-Elwahab SM, El-Tanbouly ND. Comparative metabolite profiling of four citrus peel cultivars via ultra-performance liquid chromatography coupled with quadrupole-time-of-flight-mass spectrometry and multivariate data analyses. J Chromatogr Sci 2019;57:349-60.
Tsugawa H, Cajka T, Kind T, Ma Y, Higgins B, Ikeda K, et al
. MS-DIAL: Data-independent MS/MS deconvolution for comprehensive metabolome analysis. Nat Methods 2015;12:523-6.
Dan M, Su M, Gao X, Zhao T, Zhao A, Xie G, et al
. Metabolite profiling of Panax notoginseng using UPLC-ESI-MS. Phytochemistry 2008;69:2237-44.
Kumar S, Pandey AK. Chemistry and biological activities of flavonoids: An overview. ScientificWorldJournal 2013;2013:162750.
Sachan DS, Hongu N, Johnsen M. Decreasing oxidative stress with choline and carnitine in women. J Am Coll Nutr 2005;24:172-6.
Hassan ST, Masarčíková R, Berchová K. Bioactive natural products with anti-herpes simplex virus properties. J Pharm Pharmacol 2015;67:1325-36.
Wang Y, Tang C, Zhang H. Hepatoprotective effects of kaempferol 3-O-rutinoside and kaempferol 3-O-glucoside from Carthamus tinctorius
L. on CCl4-induced oxidative liver injury in mice. J Food Drug Analysis 2015;23:317-10.
Lyu SY, Rhim JY, Park WB. Antiherpetic activities of flavonoids against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in vitro
. Arch Pharm Res 2005;28:1293-301.
Firuzi O, Lacanna A, Petrucci R, Marrosu G, Saso L. Evaluation of the antioxidant activity of flavonoids by “ferric reducing antioxidant power” assay and cyclic voltammetry. Biochim Biophys Acta 2005;1721:174-84.
Lee CH, Yang L, Xu JZ, Yeung SY, Huang Y, Chen ZY. Relative antioxidant activity of soybean isoflavones and their glycosides. Food Chem 2005;90:735-41.
Cui XX, Yang X, Wang HJ, Rong XY, Jing S, Xie YH, et al
. Luteolin-7-O-glucoside present in lettuce extracts inhibits hepatitis B surface antigen production and viral replication by human hepatoma cells in vitro
. Front Microbiol 2017;8:2425.
Biljali S, Hadjimitova VA, Topashka-Ancheva MN, Momekova DB, Traykov TT, Karaivanova MH. Antioxidant and antiradical properties of esculin, and its effect in a model of epirubicin-induced bone marrow toxicity. Folia Med 2012;54:42-9.
Procházková D, Boušová I, Wilhelmová N. Antioxidant and prooxidant properties of flavonoids. Fitoterapia 2011;82:513-23.
Bailly F, Cotelle P. Anti-HIV activities of natural antioxidant caffeic acid derivatives: Toward an antiviral supplementation diet. Curr Med Chem 2005;12:1811-8.
Ozçelik B, Kartal M, Orhan I. Cytotoxicity, antiviral and antimicrobial activities of alkaloids, flavonoids, and phenolic acids. Pharm Biol 2011;49:396-402.
Chiang LC, Chiang W, Chang MY, Ng LT, Lin CC. Antiviral activity of Plantago major extracts and related compounds in vitro
. Antiviral Res 2002;55:53-62.
Wang GF, Shi LP, Ren YD, Liu QF, Liu HF, Zhang RJ, et al
. Anti-hepatitis B virus activity of chlorogenic acid, quinic acid and caffeic acid in vivo
and in vitro
. Antiviral Res 2009;83:186-90.
Witaicenis A, Seito LN, da Silveira Chagas A, de Almeida LD Jr., Luchini AC, Rodrigues-Orsi P, et al
. Antioxidant and intestinal anti-inflammatory effects of plant-derived coumarin derivatives. Phytomedicine 2014;21:240-6.
Gravina HD, Tafuri NF, Silva Júnior A, Fietto JL, Oliveira TT, Diaz MA, et al
assessment of the antiviral potential of trans-cinnamic acid, quercetin and morin against equid herpesvirus 1. Res Vet Sci 2011;91:e158-62.
Kim KH, Tsao R, Yang R, Cui SW. Phenolic acid profiles and antioxidant activities of wheat bran extracts and the effect of hydrolysis conditions. Food Chem 2006;95:466-73.
Galabov AS, Iosifova T, Vassileva E, Kostova I. Antiviral activity of some hydroxycoumarin derivatives. Z Naturforsch C J Biosci 1996;51:558-62.
Martin-Aragón S, Benedi JM, Villar AM. Effects of the antioxidant (6,7-dihydroxycoumarin) esculetin on the glutathione system and lipid peroxidation in mice. Gerontology 1998;44:21-5.
Zhou J, Chan L, Zhou S. Trigonelline: A plant alkaloid with therapeutic potential for diabetes and central nervous system disease. Curr Med Chem 2012;19:3523-31.
Dutta M, Ghosh AK, Mohan V, Mishra P, Rangari V, Chattopadhyay A, et al
. Antioxidant mechanism(s) of protective effects of Fenugreek 4-hydroxyisoleucine and trigonelline enriched fraction (TF4H (28%)) Sugaheal against copper-ascorbate induced injury to goat cardiac mitochondria in vitro
. J Pharm Res 2014;8:798-811.
Marín L, Miguélez EM, Villar CJ, Lombó F. Bioavailability of dietary polyphenols and gut microbiota metabolism: Antimicrobial properties. Bio Med Res Int 2015;2015.
Rahimuddin SA, Khoja SM, Zuhair MM, Howell NK, Brown JE. Inhibition of lipid peroxidation in UVA-treated skin fibroblasts by luteolin and its glucosides. Europ J Lipid Sci Technol 2007;109:647-55.
Lam KY, Ling AP, Koh RY, Wong YP, Say YH. A review on medicinal properties of orientin. Adv Pharmacol Sci 2016;2016:4104595.
Li YL, Ma SC, Yang YT, Ye SM, But PP. Antiviral activities of flavonoids and organic acid from Trollius chinensis Bunge. J Ethnopharmacol 2002;79:365-8.
An F, Yang G, Tian J, Wang S. Antioxidant effects of the orientin and vitexin in Trollius chinensis
Bunge in D-galactose-aged mice. Neural Regen Res 2012;7:2565-75. [Full text]
Srinivasan M, Sudheer AR, Menon VP. Ferulic Acid: Therapeutic potential through its antioxidant property. J Clin Biochem Nutr 2007;40:92-100.
Wang Y, Chen M, Zhang J, Zhang XL, Huang XJ, Wu X, et al
. Flavone C-glycosides from the leaves of Lophatherum gracile
and theirin vitro
antiviral activity. Planta Med 2012;78:46-51.
Shibano M, Kakutani K, Taniguchi M, Yasuda M, Baba K. Antioxidant constituents in the dayflower (Commelina communis L
.) and their alpha-glucosidase-inhibitory activity. J Nat Med 2008;62:349-53.
Grochowski DM, Locatelli M, Granica S, Cacciagrano F, Tomczyk M. A review on the dietary flavonoid tiliroside. Comprehensive Rev Food Sci Food Safety 2018;17:1395-421.
Shaw CY, Chen CH, Hsu CC, Chen CC, Tsai YC. Antioxidant properties of scopoletin isolated from Sinomonium acutum
. Phytother Res 2003;17:823-5.
Kwon HJ, Kang MJ, Kim HJ, Choi JS, Paik KJ, Chung HY. Inhibition of NFkappaB by methyl chlorogenate from Eriobotrya japonica
. Molecules Cells 2000;10:241-6.
Mahmood N, Pizza C, Aquino R, De Tommasi N, Piacente S, Colman S, et al
. Inhibition of HIV infection by flavanoids. Antiviral Res 1993;22:189-99.
Willig JA. Analysis of Antiviral and Chemoprotective Effects of Strawberry Anthocyanins; 2013.
Ma SC, But PP, Ooi VE, He YH, Lee SH, Lee SF, et al
. Antiviral amentoflavone from Selaginella sinensis
. Biol Pharm Bull 2001;24:311-2.
Ibrahim E, Desoukey S, Hadad G, Salam R, Ibrahim A. Analysis of cupressuflavone and amentoflavone from Cupressus sempervirens L
. and its tissue cultured callus using HPLC-DAD method. Pharm Pharmacol Int J 2017;5:174-80.
Wu LL, Yang XB, Huang ZM, Liu HZ, Wu GX. In vivo
and in vitro
antiviral activity of hyperoside extracted from Abelmoschus manihot
(L) medik. Acta Pharmacol Sin 2007;28:404-9.
Ku SK, Zhou W, Lee W, Han MS, Na M, Bae JS. Anti-inflammatory effects of hyperoside in human endothelial cells and in mice. Inflammation 2015;38:784-99.
Kapoor R, Sharma B, Kanwar S. Antiviral phytochemicals: An overview. Biochem Physiol 2017;6:7.
Chung CY, Liu CH, Burnouf T, Wang GH, Chang SP, Jassey A, et al
. Activity-based and fraction-guided analysis of Phyllanthus urinaria
identifies loliolide as a potent inhibitor of hepatitis C virus entry. Antiviral Res 2016;130:58-68.
Yang X, Kang MC, Lee KW, Kang SM, Lee WW, Jeon YJ. Antioxidant activity and cell protective effect of loliolide isolated from Sargassum ringgoldianum
subsp. coreanum. Algae 2011;26:201-8.
Ganeshpurkar A, Saluja A. The pharmacological potential of hesperidin. Indian J Biochem Biophys 2019;56:287-300.
Williams DL, Munday P. The effect of a topical antioxidant formulation including N-acetyl carnosine on canine cataract: A preliminary study. Veterinary Ophthalmol 2006;9:311-6.
Zhang M, Wu X, Lai F, Zhang X, Wu H, Min T. Betaine inhibits hepatitis B virus with an advantage of decreasing resistance to lamivudine and interferon α. J Agricult Food Chem 2016;64:4068-77.
Ganesan B, Buddhan S, Anandan R, Sivakumar R, AnbinEzhilan R. Antioxidant defense of betaine against isoprenaline-induced myocardial infarction in rats. Mol Biol Rep 2010;37:1319-27.
Maobe MA, Gitu L, Gatebe E, Rotich H, Box P. Phytochemical analysis of phenol and flavonoid in eight selected medicinal herbs used for the treatment of diabetes, malaria and pneumonia in Kisii, Kenya. Acad J Cancer Res 2012;5:31-9.
Smith CA, O'Maille G, Want EJ, Qin C, Trauger SA, Brandon TR, et al
. METLIN: A metabolite mass spectral database. Ther Drug Monit 2005;27:747-51.
Niu CY, Wu CS, Sheng YX, Zhang JL. Identification and characterization of flavonoids from semen Zizyphi spinosae by high-performance liquid chromatography/linear ion trap FTICR hybrid mass spectrometry. J Asian Nat Prod Res 2010;12:300-12.
Keskes H, Belhadj S, Jlail L, El Feki A, Sayadi S, Allouche N. LC–MS–MS and GC–MS analyses of biologically active extracts of Tunisian Fenugreek (Trigonella foenum-graecum
L.) seeds. J Food Measurem Characterization 2018;12:209-20.
El-Sayed MA, Al-Gendy AA, Hamdan DI, El-Shazly AM. Phytoconstituents, LC-ESI-MS profile, antioxidant and antimicrobial activities of Citrus
Burm. f. Cultivar variegated pink lemon. J Pharm Sci Res 2017;9:375.
Concannon S, Ramachandran VN, Smyth WF. A study of the electrospray ionisation of selected coumarin derivatives and their subsequent fragmentation using an ion trap mass spectrometer. Rapid Commun Mass Spectrom 2000;14:1157-66.
Demarque DP, Crotti AE, Vessecchi R, Lopes JL, Lopes NP. Fragmentation reactions using electrospray ionization mass spectrometry: An important tool for the structural elucidation and characterization of synthetic and natural products. Nat Prod Rep 2016;33:432-55.
Kachlicki P, Piasecka A, Stobiecki M, Marczak Ł. Structural characterization of flavonoid glycoconjugates and their derivatives with mass spectrometric techniques. Molecules 2016;21.
Fabre N, Rustan I, de Hoffmann E, Quetin-Leclercq J. Determination of flavone, flavonol, and flavanone aglycones by negative ion liquid chromatography electrospray ion trap mass spectrometry. J Am Soc Mass Spectrom 2001;12:707-15.
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]