Structure and antioxidant activity of diarylheptanoids extracted from bark of grey alder (Alnus incana) and potential of biorefinery-based bark processing of European trees
-
Galina Telysheva
,
Tatiana Dizhbite
Abstract
The bark of trees has a big potential as a source of green chemicals. The aim of the present work was to valorise the potential of deciduous tree species with this regard. Three widely spread trees in Europe (grey alder, ash tree, aspen) were in focus as a source of polyphenols, and the yields of polyphenolic compound in the extracts were considered as evaluation criteria. The highest yields of hydrophilic extractives were found in barks of grey alder and aspen (36.8 and 22.9%, respectively). In the former, the highest antioxidant activity was found towards free radicals (DPPH• and ABTS•+) and superoxide anion radical. Open chain diarylheptanoids, mainly oregonin, were identified as the major constituents of the grey alder hydrophilic extract. In addition to oregonin, the presence of 2 linear diarylheptanoids [platyphylloside and 1,7-bis-(3,4-dihydroxyphenyl)-heptane-5-O-β-D-glucopyranoside] was confirmed. For the first time, the compounds 1,7-bis-(3,4-dihydroxyphenyl)-3-hydroxyheptane-5-O-β-D-xylopyranoside and 1,7-bis-(3,4-dihydroxyphenyl)-heptane-3-one-5-O-β-D-glucopyranoside were detected in grey alder bark. The results of experiments in vitro and in vivo have shown the high potential for diarylheptanoids-containing extracts in prophylaxis and/or treatment of diseases due to the metabolic disorders and ageing. The biological activity of grey alder extract was confirmed in in vitro experiments by incubation of human blood samples. In vivo experiments with rats also showed positive results. The conclusion is that grey alder extracts have a high potential for prevention of ageing related pathologies. Besides diarylheptanoids, the bark contains condensed tannins in commercially available quantity (12.5%). Eco-friendly wood adhesives were obtained on a tannins basis. The bark left after polyphenols isolation can be used in soil melioration and as a sorbent for the removal of oil products from water surface. The investigation of the phenolic pool of grey alder could contribute to cluster technologies within the biorefinery-based bark processing.
©2011 by Walter de Gruyter Berlin Boston
Articles in the same Issue
- Editorial
- EWLP 2010, 16th–19th August 2010, Hamburg, Germany
- Review
- Bio based fuels and fuel additives from lignocellulose feedstock via the production of levulinic acid and furfural
- Original Papers
- Optimization of steam pretreatment conditions for enzymatic hydrolysis of poplar wood
- Fungal pretreatment of pine wood to reduce the emission of volatile organic compounds
- Dilute acid pretreatment of starch-containing rice hulls for ethanol production
- Studies of the chemoenzymatic modification of cellulosic pulps by the laccase-TEMPO system
- Development of an integrated thermal and enzymatic hydrolysis for lignocellulosic biomass in fixed-bed reactors
- A larch based biorefinery: pre-extraction and extract fermentation to lactic acid
- Lignins as agents for bio-protection of wood
- Isolation and characterization of the phenolic fractions of wood pyrolytic oil
- Purification of Eucalyptus globulus water prehydrolyzates using the HiTAC process (high-temperature adsorption on activated charcoal)
- Disintegration and dissolution kinetics of wood chips in ionic liquids
- Ionic liquids as media for biomass processing: opportunities and restrictions
- Autohydrolysis of birch wood
- Solvent extraction as a means of preparing homogeneous lignin fractions
- Conditioning of SO2-ethanol-water spent liquor from spruce for the production of chemicals by ABE fermentation
- Total mass balances of SO2-ethanol-water (SEW) fractionation of forest biomass
- Lignin oxidation mechanisms under oxygen delignification conditions. Part 1. Results from direct analyses
- Lignin oxidation mechanisms under oxygen delignification conditions. Part 2: Advanced methods for the detailed characterization of lignin oxidation mechanisms
- Lignin oxidation mechanisms under oxygen delignification conditions. Part 3. Reaction pathways and modeling
- Simplified determination of total lignin content in kraft lignin samples and black liquors
- Xylan deposition onto eucalypt pulp fibers during oxygen delignification
- Dissolution of dissolving pulp in alkaline solvents after steam explosion pretreatments
- Structure and antioxidant activity of diarylheptanoids extracted from bark of grey alder (Alnus incana) and potential of biorefinery-based bark processing of European trees
- Short Note
- Binding affinities of different metal ions to unbleached hardwood kraft pulp
- Meetings
- Meetings
Articles in the same Issue
- Editorial
- EWLP 2010, 16th–19th August 2010, Hamburg, Germany
- Review
- Bio based fuels and fuel additives from lignocellulose feedstock via the production of levulinic acid and furfural
- Original Papers
- Optimization of steam pretreatment conditions for enzymatic hydrolysis of poplar wood
- Fungal pretreatment of pine wood to reduce the emission of volatile organic compounds
- Dilute acid pretreatment of starch-containing rice hulls for ethanol production
- Studies of the chemoenzymatic modification of cellulosic pulps by the laccase-TEMPO system
- Development of an integrated thermal and enzymatic hydrolysis for lignocellulosic biomass in fixed-bed reactors
- A larch based biorefinery: pre-extraction and extract fermentation to lactic acid
- Lignins as agents for bio-protection of wood
- Isolation and characterization of the phenolic fractions of wood pyrolytic oil
- Purification of Eucalyptus globulus water prehydrolyzates using the HiTAC process (high-temperature adsorption on activated charcoal)
- Disintegration and dissolution kinetics of wood chips in ionic liquids
- Ionic liquids as media for biomass processing: opportunities and restrictions
- Autohydrolysis of birch wood
- Solvent extraction as a means of preparing homogeneous lignin fractions
- Conditioning of SO2-ethanol-water spent liquor from spruce for the production of chemicals by ABE fermentation
- Total mass balances of SO2-ethanol-water (SEW) fractionation of forest biomass
- Lignin oxidation mechanisms under oxygen delignification conditions. Part 1. Results from direct analyses
- Lignin oxidation mechanisms under oxygen delignification conditions. Part 2: Advanced methods for the detailed characterization of lignin oxidation mechanisms
- Lignin oxidation mechanisms under oxygen delignification conditions. Part 3. Reaction pathways and modeling
- Simplified determination of total lignin content in kraft lignin samples and black liquors
- Xylan deposition onto eucalypt pulp fibers during oxygen delignification
- Dissolution of dissolving pulp in alkaline solvents after steam explosion pretreatments
- Structure and antioxidant activity of diarylheptanoids extracted from bark of grey alder (Alnus incana) and potential of biorefinery-based bark processing of European trees
- Short Note
- Binding affinities of different metal ions to unbleached hardwood kraft pulp
- Meetings
- Meetings
