EXTRACTION OF NATURAL COLORS WITH POTENTIAL INDUSTRIAL APPLICATION FROM SMILAX DOMINGENSIS RHIZOME
Substitution of synthetic dyes and colorants is gaining worldwide interest due to the toxicity of the most commonly used colorants. Biodiversity resources are interesting options in the search for new colorants and dyes that do not harm the environment and give alternative economic relief. Seven-year-old rhizomes of Smilax domingensis Wild., cultivated in Samayac, Guatemala, were collected, chopped and shade-dried. Two systems for solvent extractions were assayed: an exhaustive extraction with ethanol 50% v/v, and a fractionated extraction with organic solvents with different polarity followed by concentration in a rotaevaporator. Phytochemical screening was qualitatively performed by qualitative color reactions and thin layer chromatography. Dye test was done in cotton fibers using the ethanol, methanol and water extracts, as well as the powdered rhizome. The highest yield was obtained with ethanol 50% (32.2%), being the most suitable solvent for colorant extraction. The fractionated extraction gave a lower yield (20.2%), methanol (16.1%) and water (3.4%) gave the highest yields within the fractionated extraction, while the other solvents gave a yield less than 1%. Flavonoids were demonstrated in the ethanol extract and fractions, chlorogenic acid in all fractions, while rutin was demonstrated only in methanol and water fractions. No evidence of anthocyanins was found. Extract solubility and staining tests showed high industrial applicability of these extracts for natural dying. It is suggested as a possible substitute for red and orange colors used industrially since the color of the extract was less intense than its artificial counterparts, yet an interesting brownish orange color could be obtained for cotton dying and cosmetic use.
Cáceres, S., Zambrano, G., Montenegro, M. and Cáceres, A. (2014). EXTRACTION OF NATURAL COLORS WITH POTENTIAL INDUSTRIAL APPLICATION FROM SMILAX DOMINGENSIS RHIZOME. Acta Hortic. 1030, 71-75
anthocyanins, flavonoids, natural food colorants