Activity of spent coffee ground cinnamates against wood-decaying fungi in vitro

Abstract

Fungi and microbes can remarkably degrade the appearance and durability of organic materials, such as wood. The inhibitory effects of natural phenolics may offer more sustainable alternatives to preserve wood than the toxic biocides that are currently used. Although pure caffeine has been proven to have antibacterial properties, the applicability of spent coffee in wood preservation has not been determined. This work conducted in vitro tests with three brown rot and one white rot fungi and demonstrated the potential of spent coffee-derived cinnamates, analyzed with high-performance liquid chromatography, as antimicrobial agents. Spent coffee at concentrations of 1% and above in the growing media caused significant growth suppression of all of the fungi. This was not only because of the caffeine, but also the other chemicals present in the residue extracts, which demonstrated that spent coffee could be used as a source of green chemicals in wood preservative formulations.

Antifungal Activity of Organic Acies and Their Impact on Wood Decay Resistance

“…Bio-based chemicals are commonly studied as alternatives to creosote and metal salts in the field of wood preservation. The antifungal activity of many bio-based chemicals, such as tannins (Lomelí Ramírez et al 2012;Anttila et al 2013), stilbenes (Lu et al 2016), essential oils (Chittenden and Singh 2011;Cai et al 2020), bark extractives (Harun and Labosky Jr. 1985), and the derivatives of organic acids (Barbero-López et al 2018), makes them promising chemicals for transferable durability. These antifungals can be extracted from forestry and agricultural side streams, such as bark, via conventional as well as newly emerging methods (Zwingelstein et al 2020), resulting in chemical mixtures that are able to inhibit the harmful effects of wooddecaying fungi.…”

Antifungal Agents in Wood Protection—A Review

“…Various wood species impregnated with an aqueous solution of caffeine were resistant against white rot fungus ( T. versicolor ), brown rot fungi ( C. puteana , P. placenta and G. trabeum ), soft rot fungus ( Ch. globosum ), wood-staining fungi ( A. pullulans and S. pythiophila ), and molds ( A. niger , A. terreus , C. herbarum , P. variotii , P. cyclopium , P. funiculosum , P. brevicompactum , P. violacea , and T. viride ) [ 39 , 40 , 41 , 42 , 43 , 44 , 45 ]. Kobetičová et al [ 46 ] assessed the effect of non-toxic methylxanthines including caffeine and its metabolites—theobromine and theophylline on the growth of four wood-destroying fungal species ( S. lacrymans , C. puteana , G. sepiarium , and T. versicolor ) in the agar test.…”

Bio-Wastes as Aggregates for Eco-Efficient Boards and Panels: Screening Tests of Physical Properties and Bio-Susceptibility

“…In both cases, caffeine solution improved wood's biological resistance. Nevertheless, even if spent coffee grounds could be a source of chemicals that can moderate mould growth, they cannot be used to avoid the biological attack, as Barbero-López et al [77] reported. Indeed, the raw material is known as a good material to allow mould growth [78,79], as confirmed also in the present study.…”