Morphological Characters and Qualitative Leaf Phytochemistry of Two Dye Plants, Indigofera tinctoria and Phyllanthus reticulatus, in Water and Ethanol Extracts

Abstract

Weavers in North Central Timor, Indonesia, obtain their blue to black dye from two shrubs, tarum (Indigofera tinctoria L., Fabaceae) and mangsian (Phyllanthus reticulatus Poir, Phyllanthaceae). Local users often apply one name to both plants, and the leaves of the two species have never been compared under a single extraction protocol. This study aimed to establish diagnostic field characters that separate these two look-alike dye plants and, for the first time, to compare their qualitative leaf secondary metabolite profiles in water and 95% ethanol under one identical cold maceration protocol. Plants were sampled purposively from stands used by local weavers. Morphological characters were recorded by direct observation and checked against taxonomic literature, and leaf macerates were screened for nine metabolite classes using standard colour and precipitation tests. Four characters separated the species clearly in the field: compound leaf type (imparipinnate in I. tinctoria against paripinnate in P. reticulatus), lamina shape and size, fruit type (dehiscent pod against fleshy globose berry), and stem colour. The aqueous macerate of I. tinctoria gave eight positive classes and its ethanolic macerate gave six, while both macerates of P. reticulatus gave seven each. Anthocyanins were absent from all four extracts. Tannins and phenolics reacted strongly in every extract, and both ethanolic macerates gave the darkest end points. The recovered profile therefore depends on species identity and solvent polarity together. Water recovered at least as many classes as 95% ethanol in both species, which supports the simple aqueous maceration that weavers already use