# Unraveling filamentous algae as a renewable bioresource for advanced moisture-absorbent innovative aquatic fibers

## TL;DR

This study explores using filamentous algae to create sustainable, moisture-absorbent fibers for textiles, with Rhizoclonium sp. showing strong potential.

## Contribution

The study introduces Rhizoclonium sp. as a novel, renewable source for bio-based textile fibers with superior moisture absorption.

## Key findings

- Rhizoclonium sp. achieved a high biomass yield of 1.04 g dry weight L−1 after 21 days.
- Optimized cultivation increased biomass productivity by 8.6% and improved fiber flexibility.
- Rhizoclonium sp. fibers showed 12% moisture regain, outperforming cotton and lyocell.

## Abstract

Filamentous algae, characterized by high cellulose content and absence of lignin, present a promising sustainable alternative to conventional plant and synthetic fibers. The present study systematically evaluated the suitability of freshwater filamentous algae as a new resource for textile fibers, targeting applications in moisture-absorbent textiles. Among twelve strains screened, the isolate Rhizoclonium sp. emerged as the most promising candidate due to its high biomass yield (1.04 g dry weight L− 1) after 21 days of cultivation. In addition, it showed superior visible fiber flexibility following air-drying, an essential prerequisite for textile processing. Cultivation conditions were optimized (using WHM medium, pH 8, and thiamin supplementation) to maximize fiber quality, resulting in 8.6% increase in biomass productivity. Biochemical profiling of the optimized biomass revealed a significant enhancement of total carbohydrates (+ 18.0%), alongside reductions in protein (-18.4%) and ash content (-14.9%), supporting improved fiber durability and flexibility. Comparative FTIR analysis showed a strong cellulose signature and marked similarity to cotton, while also revealing high native starch content, further supporting their applicability as bio-based binders in nonwoven products. Functional characterization demonstrated that optimized Rhizoclonium sp. fibers exhibited exceptional moisture regain (~ 12%), surpassing conventional fibers such as cotton and lyocell. Overall, this study establishes native Rhizoclonium sp. as a highly versatile and renewable bioresource for innovative aquatic fibers, underpinning the development of an environmentally responsible algae-derived textile value chain.

The online version contains supplementary material available at 10.1186/s40643-026-01028-1.