Evaluation of single cell protein from yeast for the development of wood adhesives

Abstract

The use of synthetic adhesives in the wood-based panels industry has been influenced by environmental and health restrictions. The main adhesives used in the industry have been urea-formaldehyde and phenol-formaldehyde. However, as these raw materials are petroleum products and natural gas, their processes are related to global warming and they may not be available in the future. Even formaldehyde affects human health. These issues have promoted the use of natural raw materials from sustainable origin in the manufacture of adhesives, such as lignin, tannins and proteins. This research proposes the use of single cell protein extract from yeast (SCPey) as a raw material to produce novel wood adhesives. The protein contents, amino acidic composition and the molecular weight distribution of protein extracts from Rhodotorula rubra, Pichia pastoris and Sacharomyces cerevisiae were investigated. Adhesive solutions were characterized and tested through a dynamic thermo mechanical analysis (DMA). Lap joints of wood veneers were assembled using adhesive solutions in order to perform mechanical tests and evaluate the adhesive performance. Protein content of R. rubra, P. pastoris and S. cerevisiae were 72.4, 71.0 and 64.6 %, respectively. The amino acidic composition of SCPey samples promotes the content of reactive functional groups with the ones present in wood polymers. Molecular weight distribution of proteins from protein extracts ranged from 8 to 130 kDa. DMA showed that the adhesive solutions of the SCPey have a proper performance enhancing the wood adhesion. The joint strength under dry conditions with adhesives based on SCPey ranged from 2.40 to 2.99 MPa, which is similar to those obtained with UF and based on a protein isolated soy flour adhesive. Hence, the results showed that SCPey is a promising natural raw material to produce alternative wood adhesives with superior performance.

Comparative Study of Carbon Nanotubes and Lignosulfonate as Polyvinyl Acetate (PVAc) Wood Adhesive-Reinforcing Agents

“…The three-point flexion method applied over the wood sample was established with a range of temperature from 25 to 250 • C; temperature rate 10 ( • C/min); static force 275 (mN); dynamic force 250 (mN); frequency 1 Hz [34][35][36]. DMA thermal conditions were set up from room temperature to 250 • C due to the neat PVAc-D3 decomposition temperature being approximately 220 • C and considering this adhesive was modified by fillers that could eventually improve its thermal performance; the polymer decomposition range was extended up to 250 • C of temperature.…”

A Study of the Properties of UV-Aged and Low Formaldehyde Emissions Particleboards Manufactured with Bio-Based Wood Protein Adhesives

“…The same author also investigated the impact of various polysaccharide fillers on the performance of soybean and cottonseed protein adhesive [13]. Núñez et al, in 2016 [14], investigated the use of yeast single-cell protein extract (SCPey) as a raw material to produce innovative wood adhesives. Wood veneers glued with the adhesive solutions were used for mechanical testing and adhesive performance evaluation.…”

Application of Fungal Biomass for the Development of New Polylactic Acid-Based Biocomposites

“…For example, the worldwide fermentation of citric acid using filamentous fungous Aspergillus niger results in the generation of 80,000 tons/year of the FB as by-product [44]. Moreover, unlike biopolymers of plant origin such as soy protein and corn starch, FB is available all around the year, as its production is neither seasonal nor climate (geographical location)-dependent [45].…”