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- Co, Michelle, 1975-, et al.
(författare)
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Extraction of Antioxidants from Spruce (Picea abies) Bark using Eco-Friendly Solvents
- 2012
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Ingår i: Phytochemical Analysis. - : Wiley-Blackwell. - 0958-0344 .- 1099-1565. ; 23:1, s. 1-11
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Tidskriftsartikel (refereegranskat)abstract
- Introduction-Antioxidants are known to avert oxidation processes and they are found in trees and other plant materials. Tree bark is a major waste product from paper pulp industries; hence it is worthwhile to develop an extraction technique to extract the antioxidants.Objective- To develop a fast and environmentally sustainable extraction technique for the extraction of antioxidants from bark of spruce (Picea abies) and also to identify the extracted antioxidants that are abundant in spruce bark.Methodology- A screening experiment that involved three different techniques, was conducted to determine the best technique to extract antioxidants.The antioxidant capacity of the extracts was determined with DPPH (2,2-diphenyl-2’-picrylhydrazyl) assay. Pressurised fluid extraction (PFE) turned out to be the best technique and a response surface design was therefore utilised to optimise PFE. Furthermore, NMR and HPLC-DAD-MS/MS were applied to identify the extracted antioxidants.Results- PFE using water and ethanol as solvent at 160 and 180°C, respectively, gave extracts of the highest antioxidant capacity. Stilbene glucosides such as isorhapontin, piceid and astringin were identified in the extracts.Conclusion-The study has shown that PFE is a fast and environmentally sustainable technique, using water and ethanol as solvent for the extraction of antioxidants from spruce bark.
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| 2. |
- Fagerlund-Edfeldt, Amelie, et al.
(författare)
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Effect of Debarking Water from Norway Spruce (Picea abies) on the Growth of Five Species of Wood-Decaying Fungi
- 2014
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Ingår i: Zeitschrift für Naturforschung C - A Journal of Biosciences. - 0939-5075 .- 1865-7125. ; 9-10:69c, s. 418-424
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Tidskriftsartikel (refereegranskat)abstract
- Norway spruce (Picea abies) debarking water is an aqueous extract obtained as waste from the debarking of logs at paper mills. The debarking water contains a mixture of natural compounds that can exhibit diverse biological activities, potentially including fungicidal activity on some species of wood-decaying fungi. Thus, we investigated the growth rates of such fungi on agar plates to which debarking water extracts had been added. The experiment included five wood-decaying fungi, viz. Gloeophyllum sepiarium, Oligoporus lateritius, Ischnoderma benzoinum, Junghuhnia luteoalba, and Phlebia sp. Growth reduction was observed for all species at the highest tested concentrations of freeze-dried and ethanol-extracted debarking water, the ethyl acetate-soluble fraction and the diethyl ether-soluble fraction. However, the magnitude of the effect varied between different species and strains of individual species. The brown-rot fungi G. sepiarium and O. lateritius were generally the most sensitive species, with the growth of all tested strains being completely inhibited by the ethyl acetate-soluble fraction. These results indicate that development of antifungal wood-protecting agents from debarking water could potentially be a way to make use of a low-value industrial waste.
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