eversvd,+15 (7)

The small industry UMK Shibiru in Ngadirejo, Temanggung produces natural dyes from the leaves and twigs of Strobilanthes cusia using a water maceration process of three days. This study evaluates how cutting leaves and twigs into smaller sizes and varying maceration time affect dye extraction efficiency and facilitate waste utilization as fertilizer. Chopping the material increases cell wall and membrane breakdown, enhances mass transfer, and produces smaller solid residues that are easier to dry and convert into manure-based fertilizer, thus creating a valuable by-product. UV-Vis spectrophotometric analysis showed that Cusia strobilantes leaves and twigs contain two dye components with absorption peaks at 409 nm (purple) and 678 nm (red), with purple being more dominant and dye content higher in leaves than in twigs. The smaller the particle size and the longer the maceration time, the higher the absorbance, indicating more extracted dye. The best results were obtained for a size of 0.5 cm and a maceration time of 3 days, yielding for the 409 nm wavelength absorbance values of 24.295 for leaves and 10.975 for twigs, and for 678 nm wavelength 12.150 for leaves and 4.975 for twigs. Currently, the two colors are not separated, so the combined maceration product produces a dark blue color when used for fabric dyeing.