Inspired by nature: Fiber networks functionalized with tannic acid and condensed tannin-rich extracts of Norway spruce bark show antimicrobial efficacy

Tuula Jyske; Jaana Liimatainen; Jenni Tienaho; Hanna Brännström; Dan Aoki; Katsushi Kuroda; Dhanik Reshamwala; Susan Kunnas; Eelis Halmemies; Eiko Nakayama; Petri Kilpeläinen; Ari Ora; Janne Kaseva; Jarkko Hellström; Varpu S Marjomäki; Maarit Karonen; Kazuhiko Fukushima

doi:10.3389/fbioe.2023.1171908

Inspired by nature: Fiber networks functionalized with tannic acid and condensed tannin-rich extracts of Norway spruce bark show antimicrobial efficacy

Front Bioeng Biotechnol. 2023 Apr 19:11:1171908. doi: 10.3389/fbioe.2023.1171908. eCollection 2023.

Authors

Tuula Jyske¹, Jaana Liimatainen¹, Jenni Tienaho¹, Hanna Brännström², Dan Aoki³, Katsushi Kuroda⁴, Dhanik Reshamwala⁵, Susan Kunnas⁶, Eelis Halmemies⁷, Eiko Nakayama⁸, Petri Kilpeläinen¹, Ari Ora¹, Janne Kaseva⁹, Jarkko Hellström⁹, Varpu S Marjomäki⁵, Maarit Karonen¹⁰, Kazuhiko Fukushima³

Affiliations

¹ Natural Resources Institute Finland, Latokartanonkaari 9, Helsinki, Finland.
² Natural Resources Institute Finland, Teknologiakatu 7, Kokkola, Finland.
³ Department of Forest and Environmental Resources Sciences, Nagoya University, Nagoya, Japan.
⁴ Forestry and Forest Products Research Institute, Tsukuba, Japan.
⁵ Department of Biological and Environmental Science, Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland.
⁶ Natural Resources Institute Finland, Ounasjoentie 6, Rovaniemi, Finland.
⁷ Department of Chemistry, University of Jyväskylä, Jyväskylä, Finland.
⁸ Department of Environmental Science Design, Showa Women's University, Tokyo, Japan.
⁹ Natural Resources Institute Finland, Myllytie 1, Jokioinen, Finland.
¹⁰ Natural Chemistry Research Group, Department of Chemistry, University of Turku, Turku, Finland.

Abstract

This study demonstrated the antibacterial and antiviral potential of condensed tannins and tannic acid when incorporated into fiber networks tested for functional material purposes. Condensed tannins were extracted from industrial bark of Norway spruce by using pressurized hot water extraction (PHWE), followed by purification of extracts by using XADHP7 treatment to obtain sugar-free extract. The chemical composition of the extracts was analyzed by using HPLC, GC‒MS and UHPLC after thiolytic degradation. The test matrices, i.e., lignocellulosic handsheets, were produced and impregnated with tannin-rich extracts, and tannic acid was used as a commercial reference. The antibacterial and antiviral efficacy of the handsheets were analyzed by using bioluminescent bacterial strains (Staphylococcus aureus RN4220+pAT19 and Escherichia coli K12+pCGLS11) and Enterovirus coxsackievirus B3. Potential bonding of the tannin-rich extract and tannic acid within the fiber matrices was studied by using FTIR-ATR spectroscopy. The deposition characteristics (distribution and accumulation patterns) of tannin compounds and extracts within fiber networks were measured and visualized by direct chemical mapping using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and digital microscopy. Our results demonstrated for the first time, how tannin-rich extracts obtained from spruce bark side streams with green chemistry possess antiviral and antibacterial properties when immobilized into fiber matrices to create substitutes for plastic hygienic products, personal protection materials such as surgical face masks, or food packaging materials to prolong the shelf life of foodstuffs and prevent the spread of infections. However, more research is needed to further develop this proof-of-concept to ensure stable chemical bonding in product prototypes with specific chemistry.

Keywords: Picea abies; antibacterial; antiviral; bark; cellulose; phenolics; sidestream; tannins.

Grants and funding

This work was supported by the Academy of Finland’s Key Project funding “Forging ahead with Research” (InnoTrea project, decision no 305763), Academy of Finland’s project funding (ForestAntivirals project, decision no 342250), the Academy of Finland’s funding “Mobility from Finland” for T. Jyske (Inspired by nature project, decision no 316237), and the Business Finland “Co-Creation” and Co-Innovation fundings (Antiviral Fibers, decision no 40699/31/2020, and BIOPROT, decision no 4403/31/2021). The authors also gratefully acknowledge financial support from the project funded by the EU Interreg Botnia-Atlantica (TanWat) and Luke’s strategic research funding for project Added value potential of new and underutilized fiber sources in Finnish value networks of green bioeconomy: prefeasibility, prototyping, and market acceptance (VALUEPOT, no 4100-00180600). The authors acknowledge funding from the Jane and Aatos Erkko foundation (Broadly acting antivirals) and Business Finland “Research to Busines” funding (Natural antivirals) to Varpu Marjomäki group. The research mobility of E. Nakayama was supported by the Showa Women’s University Grant.