Wettability, surface free energy and cellulose crystallinity for pine wood (Pinus sp.) modified with chili pepper extracts as natural preservatives

Autor(es)

Ziglio, Analine C. ^[1] ; Sardela, Mauro R. ^[2] ; Goncalves, Debora ^[3]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Escola Engn Sao Carlos, Ave Trabalhador Sao Carlense 400, BR-13566590 Sao Carlos, SP - Brazil

^[2] Univ Illinois, Frederick Seitz Mat Res Labs, 104 S Godwin Ave, Urbana, IL 61801 - USA

^[3] Univ Sao Paulo, Inst Fis Sao Carlos, Ave Trabalhador Sao Carlense 400, BR-13566590 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Cellulose; v. 25, n. 10, p. 6151-6160, OCT 2018.
• Citações Web of Science: 2

Resumo

Fresh chili peppers (Malagueta, Red Savina and Bhut Jolokia) were used as natural finishing agents for Pinus sp. (Pinus). The solvent extraction of dried peppers produced a viscous liquid primarily containing capsicin, a pungent, lipophilic compound, and known as oleoresin capsicum (OC). Changes in surface wettability were monitored by the sessile-drop technique for samples treated with OC. The contact angles for untreated and treated Pinus provided the values of surface energy, with its polar and dispersive components, and polarity ratios. When treated with OC extracted from more pungent peppers, such as Bhut Jolokia, Pinus showed higher contact angles in non-polar probe liquids and higher polarity. The protective efficacy of OC was investigated against two wood-decay fungi, Paecilomyces variotii (soft-rot fungus) and Pycnoporus sanguineus (white-rot fungus). The treated samples, when submitted to fungal decay, exhibited reduced percentage of mass loss, which indicated that OC can afford surface protection under the conditions studied here. Changes in cellulose crystallinity were observed owing to distinct contributions from amorphous and crystalline zones of Pinus after fungal decay. (AU)

• Processo FAPESP: 13/14262-7 - Filmes nanoestruturados de materiais de interesse biológico
• Beneficiário: Osvaldo Novais de Oliveira Junior
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 14/02766-3 - Sistemas epidérmicos para a análise de biofluídos
• Beneficiário: Debora Goncalves
• Modalidade de apoio: Bolsas no Exterior - Pesquisa