Spruce Bark—A Source of Polyphenolic Compounds: Optimizing the Operating Conditions of Supercritical Carbon Dioxide Extraction

Abstract

The present study described the optimization of the extraction process with carbon dioxide in supercritical state for obtaining extractives, especially polyphenols from softwood bark, Norway spruce (Picea abies (L.) Karst.). Using a full 23 factorial design of experiments, the effect of varying the working parameters on the yield of extractives was studied for the following ranges: temperature 40–100 °C, pressure 1050–9000 psi (7.2–62 MPa), and concentration of EtOH/water co-solvent mixture 40–96.6%. In addition, total phenolics content and the antioxidant capacity of the spruce bark extract were determined. The optimum operating conditions for the yield of extractives were identified as 73 °C, 6465 psi (44.5 MPa), and 58% EtOH/water cosolvent concentration for a yield of 8.92%. The optimum conditions for achieving a total phenolics content of 13.89 mg gallic acid equivalent (GAE)/g dry extract were determined as: 45 °C, 1050 psi (7.2 MPa), and 96.6% EtOH/water mixture.

Bioprocess development of 2, 3-butanediol production using agro-industrial residues

“…Because of such inhibitory compounds, a retarded growth, and corresponding less 2,3-BDO production were noted with spruce biomass hydrolysate compared to oat hull. Similar observation was noted with Strizincova et al, in spruce bark biomass [ 27 ]. Phenolic compounds and degradation products of sugars are inhibitory compounds for microbial growth and fermentation.…”

Investigation of Total Phenolic Content and Antioxidant Activities of Spruce Bark Extracts Isolated by Deep Eutectic Solvents

“…It is known that the recovery of polar compounds from samples can be enhanced varying the extraction conditions (diffusivity, density, viscosity) and with the addition of a co-solvent [53]. As shown in Table 1, viscosity decreases with increasing HBD content.…”

“Smart Extraction Chain” with Green Solvents: Extraction of Bioactive Compounds from Picea abies Bark Waste for Pharmaceutical, Nutraceutical and Cosmetic Uses

“…Antioxidant compounds are the key shields protecting cells from free radical onslaughts that lead to the progression of chronic and degenerative diseases [ 16 ]. In this context, we need to find new and safe sources of antioxidants especially related to potential application in nutraceuticals and cosmetics.…”