Carbohydrates valorization of Quinoa (Chenopodium quinoa) stalk in xylooligosaccharides and carotenoids as emergent biomolecules

Rosas Vega F.E.; Sanchez Muñoz S.; Severo Gonçalves I.; Terán Hilares F.; Rocha Balbino T.; Soares Forte M.B.; da Silva S.S.; dos Santos J.C.; Terán Hilares R. · Industrial Crops and Products (2023) · DOI: 10.1016/j.indcrop.2023.116274

Resumen

Quinoa (Chenopodium quinoa) stalk (QS) is an unvalued and renewable lignocellulosic waste. Aiming to its valorization, autohydrolysis process (178 °C and 10 bar) for xylooligosaccharides (XOS) production and enzymatic hydrolysate of residual solid for carotenoids production by Rhodotorula glutinis were evaluated. The highest yield of XOS (79 mg/g of biomass) containing mainly xylotetraose (X4) to xylohexaose (X6) was achieved in 20 min of process, while high xylobiose (X2, 18 mg/g of QS) and xylotriose (X3, 18 mg/g of QS) contents were observed in 45 min. In ultrafiltration-UF using membrane with nominal MWCO of 10 kDa, higher permeate flux was observed at pH 6.6 than at lower pH values (3.6, 4.6, and 5.6). In the retentate after nanofiltration-NF (150–300 Da), 56 % of total XOS (X2-X6) was recovered. Finally, 4.1 mg of carotenoids/g of dry cells weight, corresponding to 6.27 mg of carotenoids/g of total sugar consumed, were produced by the yeast using residual solids hydrolysate. Therefore, quinoa stalk was shown as an interesting source for high value biomolecules production.

Instituciones: Universidad Nacional José María Arguedas; Universidad Católica de Santa María