title: Characterisation of novel pH indicator of natural dye Oldenlandia umbellata L.
abstract: Oldenlandia umbellata L., commonly known as 'chay root', belongs to the family Rubiaceae and is one of the unexplored dye-yielding plants. The roots from this plant are the sources of red dye. Extraction protocol and dye characterisation have not been completely studied so far in this plant. Hence, in this article we have used UV spectrophotometry, thin layer chromatography, GC-MS, high-performance liquid chromatography and NMR to identify the five major colouring compounds, including 1,2,3-trimethoxyanthraquinone, 1,3-dimethoxy-2-hydroxyanthraquinone, 1,2-dimethoxyanthraquinone, 1-methoxy-2-hydroxyanthraquinone and 1,2-dihydroxyanthraquinone. It showed application feasibility as a new pH indicator.
authors.affiliation: School of Biotechnology, Chemical and Biomedical Engineering, VIT University, Vellore, India. rsiva77in@rediffmail.com
authors.forename: Siva
authors.initials: S
authors.lastname: Ramamoorthy
authors.forename: Gaurav
authors.initials: G
authors.lastname: Mudgal
authors.forename: D
authors.initials: D
authors.lastname: Rajesh
authors.forename: F
authors.initials: F
authors.lastname: Nawaz Khan
authors.forename: V
authors.initials: V
authors.lastname: Vijayakumar
authors.forename: C
authors.initials: C
authors.lastname: Rajasekaran
mesh_terms: D000880:Anthraquinones / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D004396:Coloring Agents / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D032067:Oldenlandia / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry
chemical_list: D000880:Anthraquinones; D004396:Coloring Agents; D007202:Indicators and Reagents; C010078:alizarin