Preparation Method of Indigo Standard Solution and Variation of Indigo Contents in Blue Dye Extract from Breeding Lines of Persicaria tinctoria H. Gross

Abstract

: This study was carried out to find out the optimum method of preparation of indigo standard solution and its stability, and to investigate the indigo contents in Niram, blue dye extract, from a total of 7 indigo plants and 34 breeding lines of Persicaria tinctoria H. Gross. Proper solvent for indigo standard was dimethyl sulfoxide (DMSO), and appropriate concentration was 1 ㎎ of indigo in 10 mL of DMSO. Absorbance value of UV/Vis Spectrophotometer at 620 ㎚ of standard solution was changed decreasingly 12 hours after the preparation of standard solution irrespective of the storage conditions such as temperature and light. Average value of absorbance of 8-fold diluted standard solutions prepared daily during 16 days was 0.210 ± 0.005, indicating the powder of indigo compound was stable chemically. Calibration curve was made for quantitative analysis of indigo of 7 Niram samples, and indigo contents ranged from 0.69% to 18.76% showing relatively larger variation. Across all 34 breeding lines, the range of indigo content was from 7.9 ㎎ to 56.4 ㎎ per 100 g of fresh leaves, averaging 25.2 ㎎ of indigo content and showing a 47.7% coefficient of variation.

Genotoxicity testing of Persicariae Rhizoma (Persicaria tinctoria H. Gross) aqueous extracts

“…In addition, synthetic indigo of technical grade or 98% purity has exhibited mutagenic effects in the Salmonella /mammalian microsome assay ( 23 ) and also in the Ames test ( 25 ). PR is known to contain purple indirubin and blue indigo ( 15 ), and has been traditionally used as anti-inflammatory and detoxification agent in Korea ( 14 ). Until now, no preclinical studies of PR extracts containing indigo and indirubin, have been performed, to the best of our knowledge.…”

“…Persicariae Rhizoma (PR) is dried stem parts of Persicaria tinctoria H. Gross (Polygonaceae), and has been traditionally used as an anti-inflammatory and detoxification agent in Korea ( 14 ). PR contains two biologically active anti-inflammatory and antioxidative dyes, namely purple indirubin and blue indigo ( 15 ). Indirubin, a 3,2′-bisindole isomer of indigo, was first identified as the active ingredient of a traditional Chinese medicine preparation, Danggui Longhui Wan, which is used to treat various chronic diseases ( 16 ).…”

Inhibitory effects of Persicariae Rhizoma aqueous extracts on experimental periodontitis and alveolar bone loss in Sprague-Dawley rats

“…Persicariae Rhizoma (PR) is dried stem parts of Persicaria tinctoria H. Gross (Polygonaceae), and has been traditionally used as anti-inflammatory and detoxifying agent in Korea (12). PR contains two biologically active anti-inflammatory and antioxidative dyes, namely purple indirubin and blue indigo (13). Indirubin, a 3,2'-bisindole isomer of indigo, was initially identified as the active ingredient of a traditional Chinese medicine preparation, Danggui Longhui Wan, which is used to treat various chronic diseases (14).…”