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Title: Bacterial Cellulose Purification with Non-Conventional, Biodegradable Surfactants
Bacterial cellulose (BC) is a versatile biopolymer with significant potential across biomedical, food, and industrial applications. To remove bacterial contaminants, such as protein and DNA, BC pellicles undergo purification, which traditionally relies on harsh alkali treatments, such as sodium hydroxide or strong surfactants, which present environmental concerns. In response, this study evaluates the efficacy of various non-conventional surfactants—both non-biodegradable and biodegradable—as alternatives for BC purification. Among the surfactants tested, sodium cocoyl isethionate (SCI), a mild anionic and biodegradable surfactant, emerged as particularly effective, achieving an 80.7% reduction in protein content and a 65.19% reduction in double-stranded DNA (dsDNA) content relative to untreated samples. However, these advantages were not without additional challenges, such as the appearance of residual surfactants. Given SCI’s promising performance and biodegradability, it was further examined in two-step treatment protocols; additionally, sodium dodecyl sulfate (SDS) was also examined as a more traditional anionic surfactant as well as NaOH. For the two-step treatment protocol, BC pellicles were treated with one reagent for 3 h, followed by a second reagent for an additional 3 h. Notably, by using NaOH as the final step in the two-step treatment protocol, residual surfactant was not detected in the FTIR analysis. Overall, this work demonstrates that SCI, in addition to subsequent NaOH treatment, can be used as a surfactant-based approach for BC purification, representing a potential environmentally friendly alternative to traditional surfactant-based approaches for BC purification.  more » « less
Award ID(s):
2236940
PAR ID:
10567725
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Multidisciplinary Digital Publishing Institute
Date Published:
Journal Name:
Polysaccharides
Volume:
5
Issue:
4
ISSN:
2673-4176
Page Range / eLocation ID:
857 to 871
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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