In a new study that was published in the journal Environmental Technology and Innovation, Prithvi along with his co-authors describe a novel process to degum ramie (Boehmeria nivea L.) is one of the oldest known fiber crops and one of the strongest natural fibers. For textile processing industry, the fiber needs to be degummed to a gum content below 6%. Conventionally, ramie is degummed by using chemicals like hot alkali solutions (sodium sulfate, sodium hydroxide or combination of both) followed by hydrogen peroxide treatment for bleaching or by water retting, both of which generate significant amount of effluent.
In the paper, the authors designed, developed, and optimizedan enzymatic fiber degumming process. First, a Partially Purified Enzyme Solution (PPES) containing pectinase, cellulase and xylanase was co-produced via ultrasound-assisted fermentation of orange peels using Bacillus subtilis ABDR01. Then, degumming with PPES was optimized for pH, temperature, incubation time and PPES concentration. Finally, three sets of ultrasound-assisted degumming experiments — chemical, enzymatic, and coupled enzymatic-chemical degumming with reduced alkali concentration (0.5% NaOH, 30 min) were performed. Chemical degumming for 2 h with 1% NaOH at 98 °C resulted in residual gum content of 5.9%, whereas ultrasound-assisted (30 min, 25 kHz) chemical degumming reduced the gum content to 3.1%. At a pH of 7.5, temperature of 45 °C, 30 h incubation and 2% PPES, gum removal efficiency of >60% and fibers with <10% residual gum were produced. Coupling the ultrasound-assisted enzymatic degumming with reduced alkali chemical degumming resulted in gum content of <3%.
Yadav, A., Simha, P., Sathe, P., Gantayet, L. M., & Pandit, A. (2022). Coupling chemical degumming with enzymatic degumming of ultrasound pre-treated ramie fiber using Bacillus subtilis ABDR01. Environmental Technology & Innovation, 102666.