Tryptanthrin Content in Isatis tinctoria Leaves - A Comparative Study of Selected Strains and Post-Harvest Treatments

Abstract

Tryptanthrin is a pharmacologically active compound in the anti-inflammatory herb Isatis tinctoria, with potent inhibitory activity on prostaglandin and leukotriene synthesis and on inducible NO synthase. The tryptanthrin content of five defined woad strains was analyzed in dependence of the time of harvest and post-harvest treatment. Tryptanthrin was determined by a validated ESI-LC-MS isotope dilution assay with d ₈-tryptanthrin as internal standard. The tryptanthrin concentration in freeze-dried leaf samples was low. Drying at ambient temperature led to a significant increase of tryptanthrin concentration, but the highest concentrations were found when leaves were dried at 40 °C. Tryptanthrin content in fermented woad leaves was below the limit of quantification. Tryptanthrin appears thus to be a product of post-harvest processes, but details of its formation remain to be elucidated.

Key words

Isatis tinctoria - Brassicaceae - woad - tryptanthrin - anti-inflammatory - ESI LC-MS - isotope dilution - post-harvest modification

References

• 1 Hurry J B. The woad plant and its dye. Oxford University Press London; 1930
• 2 Hamburger M. Isatis tinctoria - From the rediscovery of an ancient medicinal plant towards a novel anti-inflammatory phytopharmaceutical.  Phytochemistry Rev. 2002;  1 333-344
• 3 Danz H, Stoyanova S, Wippich P, Brattström A, Hamburger M. Identification and isolation of the cyclooxygenase-2 inhibitory principle in Isatis tinctoria .  Planta Medica. 2001;  67 411-6
• 4 Danz H, Stoyanova S, Thomet O, Simon H U, Dannhardt G, Ulbrich H, Hamburger M. Inhibitory activity of tryptanthrin on prostaglandin and leukotriene synthesis.  Planta Medica. 2002;  68 875-80
• 5 Ishihara T, Kohno K, Ushio S, Iwaki K, Ikeda M, Kurimoto M. Tryptanthrin inhibits nitric oxide and prostaglandin E₂ synthesis by murine macrophages.  Eur J Pharmacol. 2000;  407 197-204
• 6 Honda G, Tosiriuk V, Tabata M. Isolation of an antidermatophytic, tryptanthrin, from indigo plants, Polygonum tinctorium and Isatis tinctoria .  Planta Medica. 1980;  38 275-6
• 7 Recio M C, Hamburger M, Rios J L. In vivo anti-inflammatory activity of Isatis tinctoria extracts and tryptanthrin.  Abstract book, 50th Annual Congress of Society of Medicinal Plant Research 2002. Canigueral S, editor Carlet (Valencia); CITA Publicaciones y Documentacion 2002: p 94
• 8 Heinemann C, Schliemann-Willers S, Oberthür C, Hamburger M, Elsner P. Prevention of experimentally induced irritant contact dermatitis by Isatis tinctoria and tryptanthrin and its impact on UVB-induced erythema.  Planta Medica. 2004;  70 385-90
• 9 Danz H, Baumann D, Hamburger M. Quantitative determination of the dual COX-2/5-LOX inhibitor tryptanthrin in Isatis tinctoria by ESI-LC-MS.  Planta Medica. 2002;  68 152-7
• 10 Benthin B, Danz H, Hamburger M. Pressurized liquid extraction (PLE) of medicinal plants.  J Chromatogr A. 1999;  837 211-9
• 11 Oberthür C, Hoffmann B, Hamburger M. Synthesis of d-tryptanthrin.  Pharmazie. 2002;  57 586-7
• 12 Oberthür C, Heinemann C, Elsner P, Benfeldt E, Hamburger M. A comparative study on the skin penetration of pure tryptanthrin and tryptanthrin in Isatis tinctoria extract by dermal microdialysis coupled with isotope dilution ESI-LC-MS.  Planta Medica. 2003;  69 385-9
• 13 Elliott M C, Stowe B B. A novel sulphonated natural indole.  Phytochemistry. 1970;  9 1629-32
• 14 Lockwood G B, Belkhiri A. Glucosinolate spectrum of some Algerian crucifers.  Pl Syst Evol. 1991;  176 11-20
• 15 Fréchard A, Fabre N, Péan C, Montaut S, Fauvel M T, Rollin P, Fouraste I. Novel indole-type glucosinolates from woad (Isatis tinctoria L.)  Tetrahedron Lett. 2001;  42 9015-7
• 16 Oberthür C, Schneider B, Graf H, Hamburger M. The elusive indigo precursors in woad (Isatis tinctoria L.) - Identification of the major indigo precursor, isatan A, and a structure revision of isatan B.  Chem Biodiv. 2004;  1 174-82
• 17 Kokobun T, Edmonds J, John P. Indoxyl derivatives in woad in relation to medieval indigo production.  Phytochemistry. 1997;  49 79-87
• 18 Maugard T, Enaud E, Choisy O, Legoy M D. Identification of an indigo precursor from leaves of Isatis tinctoria (woad).  Phytochemistry. 2001;  58 897-904