Cellulose nanocrystals from grape pomace: Production, properties and cytotoxicity assessment

Caroline C S Coelho; Michele Michelin; Miguel A Cerqueira; Catarina Gonçalves; Renata V Tonon; Lorenzo M Pastrana; Otniel Freitas-Silva; António A Vicente; Lourdes M C Cabral; José A Teixeira

doi:10.1016/j.carbpol.2018.03.023

Cellulose nanocrystals from grape pomace: Production, properties and cytotoxicity assessment

Carbohydr Polym. 2018 Jul 15:192:327-336. doi: 10.1016/j.carbpol.2018.03.023. Epub 2018 Mar 13.

Affiliations

¹ PPGCAL/Instituto de Química, UFRJ, Cidade Universitária, Ilha do Fundão, 21949-900, Rio de Janeiro, RJ, Brazil; Embrapa Agroindústria de Alimentos, Av. das Américas 29501, 23020-470, Rio de Janeiro, RJ, Brazil; Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
² Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal. Electronic address: mimichelin@ceb.uminho.pt.
³ International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330, Braga, Portugal.
⁴ PPGCAL/Instituto de Química, UFRJ, Cidade Universitária, Ilha do Fundão, 21949-900, Rio de Janeiro, RJ, Brazil; Embrapa Agroindústria de Alimentos, Av. das Américas 29501, 23020-470, Rio de Janeiro, RJ, Brazil.
⁵ Embrapa Agroindústria de Alimentos, Av. das Américas 29501, 23020-470, Rio de Janeiro, RJ, Brazil.
⁶ Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.

PMID: 29691028
DOI: 10.1016/j.carbpol.2018.03.023

Abstract

Cellulose nanocrystals (CNCs) were obtained from grape pomace through chemical and physical pretreatments. Bleached cellulose pulp was subjected to acid hydrolysis (AH) for 30 or 60 min and an ultrasound treatment to obtain CNCs (AH_30S and AH_60S). Compositional analyses of untreated (UGP) and pretreated (PGP) grape pomace showed the effectiveness of pretreatment in removing non-cellulosic components, recovering 80.1% cellulose in PGP (compared to 19.3% of UGP). Scanning and transmission electron microscopies were used to evaluate the CNCs morphology. AH in combination with ultrasound treatment led to needle-shaped structures and apparently more dispersed suspensions. Crystallinity index and thermal stability were studied by X-ray diffraction and thermogravimetric analysis, respectively. The AH_60S sample presented high aspect ratio, crystallinity and thermal stability. CNCs toxicity was evaluated by exposing Caco-2 cells to CNCs suspension and evaluating their viability. Results showed that CNCs are non-toxic, opening the opportunity for their use on food and pharmaceutical applications.

Keywords: Biopolymer; Lignocellulosic; Nanotechnology; Pretreatment.