Here is a starting point:

LC-APCI-MS method for detection and analysis of tryptanthrin, indigo, and indirubin in Daqingye and Banlangen (vol 43, pg 346, 2007)

By:Liau, BC (Liau, Bing-Chung); Jong, TT (Jong, Ting-Ting); Lee, MR (Lee, Maw-Rong); Chen, SS (Chen, Shih-Shiung)

JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS

Volume: 44

Issue: 3

Pages: 829-829

Special Issue: SI

DOI: 10.1016/j.jpba.2007.06.029

Published: JUL 27 2007

Differences in leaf yield and indigo precursors production in woad (Isatis tinctoria L.) and Chinese woad (Isatis indigotica Fort.) genotypes

By:Angelini, LG (Angelini, Luciana G.); Tozzi, S (Tozzi, Sabrina); Di Nasso, NNO (Di Nasso, Nicoletta Nassi o)

FIELD CROPS RESEARCH

Volume: 101

Issue: 3

Pages: 285-295

DOI: 10.1016/j.fcr.2006.12.004

Published: MAR 15 2007

Quantification of active principles and pigments in leaf extracts of Isatis tinctoria by HPLC/UV/MS

By:Mohn, T (Mohn, Tobias); Potterat, O (Potterat, Olivier); Hamburger, M (Hamburger, Matthias)

PLANTA MEDICA

Volume: 73

Issue: 2

Pages: 151-156

DOI: 10.1055/s-2007-967105

Published: FEB 2007

OPTIMIZATION OF TEMPERATURE AFFECTED EXTRACTION OF INDIGO DYE IN THE LEAF EXTRACTS OF POLYGONUM TINCTORIUM Ait. CULTIVATED IN POLAND - PRELIMINARY STUDIES

By:Kukula-Koch, W (Kukula-Koch, Wirginia)[ 1 ] ; Glowniak, K (Glowniak, Kazimierz)[ 1 ] ; Koch, W (Koch, Wojciech)[ 2 ] ; Kwiatkowski, S (Kwiatkowski, Stanislaw)[ 1 ]

ACTA POLONIAE PHARMACEUTICA

Volume: 70

Issue: 3

Pages: 579-583

Published: MAY-JUN 2013

Isatis tinctoria L.: biomass production and indigo dye yield as influenced by mineral or organic nitrogen fertilization

By:Orsini, R (Orsini, R.)[ 1 ] ; Aquilanti, L (Aquilanti, L.)[ 1 ] ; Osimani, A (Osimani, A.)[ 1 ] ; Serrani, L (Serrani, L.)[ 1 ] ; Baldini, G (Baldini, G.)[ 1 ] ; Seddaiu, G (Seddaiu, G.)[ 2 ] ; De Sanctis, G (De Sanctis, G.)[ 3,4 ] ; Santilocchi, R (Santilocchi, R.)[ 1 ]

AGROCHIMICA

Volume: 56

Issue: 6

Pages: 292-308

Published: NOV-DEC 2012