Extraction and Application Extraction and Application of Natural Dye from Silkworm Manure: Cultivating Identity and Sustainability in Community Handwoven Silk

Abstract

This research aimed to investigate the extraction and application of natural dye derived from silkworm manure, an agricultural by-product of the traditional mulberry–silkworm farming system, for the development of handwoven silk textiles and the enhancement of community identity and sustainability. The study examined the effects of solvent volume and extraction time on dye extraction using 10 g of silkworm manure. The results revealed that the dye extracts exhibited pH values ranging from 7.38 to 7.92, indicating neutral to slightly alkaline characteristics. The extraction condition using 200 mL of solvent for 120 minutes yielded the highest pH value (7.92±0.03), while extraction with 300 mL of solvent for 120 minutes produced the highest hue value (69.31±0.92), resulting in a distinctive dark green–brown coloration. Analysis of L*, a*, and b* color values showed that extraction with 100 mL of solvent for 90 minutes provided the highest brightness and color intensity. Increasing solvent volume and extraction time significantly reduced color intensity (p≤0.05), highlighting the importance of controlling extraction conditions.

Silk dyeing under optimal extraction conditions combined with natural mordants did not significantly affect color values; however, it influenced the acid–base balance of the dye extract, particularly when ash water was used, resulting in increased pH. Color fastness tests demonstrated good performance, with rubbing fastness rated at 4–5 and washing fastness at 3–4, while the mechanical properties of silk fibers and fabrics remained within acceptable standards. Furthermore, the development of prototype handwoven silk products dyed with silkworm manure showed a high level of consumer acceptance and demonstrated tangible economic value creation. Overall, the findings confirm that silkworm manure-based natural dye represents a viable local innovation aligned with the Bio–Circular–Green (BCG) economy concept, contributing to waste reduction, value-added product development, and the sustainable advancement of community-based handwoven silk production.