Total Phenolic Content, Antioxidant and Antibacterial Activities of Three Verbascum Species from Iran


The genus Verbascum L. belongs to the family Scrophulariaceae and includes plants that have been used widely in traditional medicine for a long time. Methanolic extracts of three Verbascum species from flora of Iran were in vitro screened for their possible antioxidant activities by three complementary test systems, namely DPPH free radical-scavenging, metal chelating activity and β-carotene/linoleic acid. The total phenol and flavonoid contents of the methanolic extracts from the aerial parts were measured by Folin Ciocalteu and AlCl3 assays, respectively. In addition, antibacterial activities of the methanolic extracts were studied by disc diffusion method against 3 Gram positive and Gram negative bacteria. Results showed that the methanolic extract of V. sinuatum contains the highest amount of phenolic compounds and of V. speciosum represents the highest flavonoid content. Results from antioxidant activity assays showed that the studied extracts are more active than ascorbic acidas a synthetic antioxidant in DPPH radical scavenging assay, but represent lower activity in metal-chelating assay. In β-carotene/linoleic acid system, oxidation of linoleic acid was effectively inhibited by V. speciosum extract (58.4±18.1mg/g), followed by V. sinuatum (51.41±2.28 mg/g). In addition, methanolic extracts of three Verbascum species showed strong antibacterial activity against all tested bacteria.


1. Halliwell B. The antioxidant paradox. Lancet 2000;355: 1179-1180.

2. Heinecke JW. Oxidative stress: new approaches to diagnosis and prognosis in atherosclerosis. The Am J Cardiol. 2003;91:12A-16A.

3. Metodiewa D, Koska C. Reactive oxygen species and reactive nitrogen species: relevance to cyto(neuro) toxic events and neurologic disorders. An overview. Neurotox Res.1999;1:197-233.

4. Maxwell SRJ. Prospects for the use of antioxidant therapies. Drugs1995;49:345-361.

5. Noguchi N, Niki E. Phenolic antioxidants: A rationale for design and evaluation of novel antioxidant drug for atherosclerosis. Free Rad Biol and Med.2000;28:1538-1546.

6. Gazzani G, Papetti A, Massolini G, Daglia M. Anti and Prooxidants activity of water soluble components of some common diet vegetables and the effect of thermal treatment. J Agric Food Chem.1998; 46: 4118-4122.

7. Larson RA. The antioxidants of higher plants. Phytochemistry1988;27:969-978.

8. Velioglu YS, Mazza G, Gao L, Oomah BD. Antioxidant activity and total phenolics in selected fruits, vegetables and grain products. J Agric Food Chem. 1998;46:4113-4117.

9. Vinson JA, Hao Y, Su X, Zubik L. Phenol antioxidant quantity and quality in foods: vegetables. J Agric Food Chem.1998;46:3630-34.

10. Huber-Morath A. Verbascum L. In: Davis PH [ed.], Flora of Turkey and the East Aegean Islands, Edinburgh: Edinburgh Univ Press, 1978; 6: 461-603.

11. Valdes B. Scrophulariaceae. In: Valdes B, Talvera S, Fernandez Galiano E [eds.], Flora vascular De Andalucia Occidental, Barcelona: Ketres, 1987;2:486-547.

12. Zohary M. Geobotanical Foundations of Middle East (Fisher, Stuttgart) Jerusalem: Israel, Hebrew University, 1973, pp. 307-329.

13. Sharifnia F. Notes on the distribution and taxonomy of Verbascum in Iran. Iranian J Bot. 2007;31: 30-32.

14. Judd WS, Campbell CS. Kellogg EA, Stevens PF. Plant Systematic: A Phylogenetic Approach. Sinauer, Sunderland, 1999, pp. 576.

15. Hoffman D. The Herbal Handbook: A User's Guide to Medicinal Herbalism. Healing Arts Press Rochester, 1988, pp. 67.

16. Berk SA. The Naturalist's Herb Guide. New York: Black Dog and Leventhal Publishers, 1996, pp. 162.

17. Mabey R. The new age herbalist. New York: Macmillan Publishing Company, 1988, pp. 113.

18. Grieve M. A Modern Herbal (Vol. II). The Medicinal, Culinary, Cosmetic, and Economic Properties, Cultivation and Folklore of Herbs, Grasses, Fungi, Shrubs and Trees with all their Modern Scientific Uses. New York: Dover Publications, 1981, pp. 562-566.

19. Singleton VL, Rossi JA. Colorimetry of total phenolics with phosphomolybdic-phosphotungstic acid reagents. Am J Enol Vitic. 1965;16:144-158.

20. Chang C, Yang M, Wen H, Chern J. Estimation of Total Flavonoid Content in Propolis by Two Complementary Colorimetric Methods. J Food Drug Anal. 2002;10:178-182.

21. Mensor LL, Menezes FS, Leitao GG, Reis AS, Santos TS, Coube CS. Screening of Brazilian plant extracts for antioxidant activity by the use of DPPH free radical method. Photother Res. 2001; 15:127-130.

22. Koleva II, Van Beek TA, Linssen JPH, De Groot A, Evstatieva LN. Screening of plant extracts for antioxidant activity, a comparative study on three testing methods. Phytochem Anal. 2002;13: 8-17.

23. Dinis TCP, Madeira VMC, Almeida MLM. Action of phenolic derivates (acetoaminophen, salycilate and 5-aminosalycilate) as inhibitors of membrane lipid peroxidation and as peroxyl radical scavengers. Arch Biochem Biophys. 1994; 315: 161-169.

24. Barriere C, Centeno D, Lebert A, Leroy-Setrin S, Berdague JL, Talon R, Talhouk SN. Roles of superoxide dismutase and catalase of Staphylococcus xylosus in the inhibition of linoleic acid oxidation. FEMS Microbiol Lett. 2001; 201: 181–185.

25. Bauer AW, Kirby WM, Sherries JC, Turck M. Antibiotic susceptibility testing by single disk method. American J Clin Pathol. 1966; 45: 493–496.

26. Decker EA. Phenolics: Prooxidants or Antioxidants? Nutr Rev. 1997; 55: 396-407.

27. Shahidi F, Janitha PK, Wanasundara PD. Crit Rev Food Sci Nutr. 1992; 32: 67-103.

28. Das NP, Pereira TA. Effect of flavonoids on thermal auto oxidation of Palm oil: structure- activity relationship. J Am Oil Chem Soc. 1990; 44:255-258.

29. Younes M. Inhibitory action of some flavonoids on enhanced spontaneous lipid peroxidation following glutathione depletion. Planta Med. 1981; 43:240-245.

30. Vaya J, Belinky PA, Aviram M. Antioxidant constituents fromlicoriceroots: Isolation, structure elucidation and antioxidative capacity toward LDL oxidation. Free Rad Biol Med. 1997; 23(2): 302-313.

31. Sacchetti G, Maietti S, Muzzoli M, Scaglianti M, Manfredini S, Radice M, Bruni R. Comparative evaluation of 11 essential oils of different origin as functional antioxidants, antiradicals and antimicrobials in foods. Food Chem. 2005; 91: 621–632.

32. Gyamfi MA, Yonamine M, Aniya Y. Free-radical scavenging action of medicinal herbs from Ghana Thonningia sanguinea on experimentally- induced liver injuries. Gen Pharmacol. 1999; 32(6): 661- 667.

33. Ozturk M, Ozturk FA, Duru ME, Topcu G. Antioxidant activity of stem and root extracts of Rhubarb (Rheum ribes): An edible Med plant. Food Chem. 2007; 103: 623-630.

34. Siddaraju MN, Dharmesh SM. Inhibition of gastric H+, K+-ATPase and Helicobacter pylori growth by phenolic antioxidants of Curcuma amada. J Agric Food Chem. 2007; 55: 7377-7386.

35. Meir S, Kanner J, Akiri B, Philosof-Hadas S. Determination and involvement of aqueous reducing compounds in oxidative defense systems of various senescing leaves. J Agric Food Chem. 1995; 43: 1813-1817.

36. Yamaguchi F, Ariga T, Yoshimura Y, Nakazawa H. Antioxidative and Anti-glycation activity of garcinol from Garcinia indica fruit rind. J Agric Food Chem. 2000; 48(2):180-185.

37. Smith C, Mitchinson MJ, Arouma OI, Halliwell B. Stimulation of lipid peroxidation and hydroxyl radical generation by the contents of human atherosclerosis lesions.Biochem J. 1992; 15: 905- 910.

38. Tepe B, Sokmen M, Akpulat HA, Yumrutas O, Sokmen A. Screening of antioxidative properties of the methanolic extracts of Pelargonium endlicherianum Fenzl., Verbascum wiedemannianum Fisch. & Mey., Sideritis libanotica Labill. subsp. linearis (Bentham) Borm., Centaurea mucronifera DC. and Hieracium cappadocicum Freyn from Turkish flora. Food Chem. 2006; 98: 9–13.

39. Senatore F, Rigano D, Formisano C, Grassia A, Basile A, Sorbo S. Phytogrowth-inhibitory and antibacterial activity of Verbascum sinuatum. Fitoterapia 2007; 78: 244–247.

40. Amirnia R, Khoshnoud H, Alahyary P, Ghiyasi M, Tajbakhsh M, Valizadegan O. Antimicrobial activity of Verbascum speciosum against three bacteria strains. Fresenius Environ Bull. 2011; 20: 690-693.