Characterization of Major Components in Barks from Five Canadian Tree Species


  • Zeen Huang
  • Ning Yan


Barks, extractives, Canadian tree species, chemical composition, total phenolics, formaldehyde-condensable polyphenols, antioxidant activity, FT-IR


In this study, the major components in barks from five Canadian tree species and their chemical and biological properties were characterized. The extractives soluble in hexane, ethanol, and 1% NaOH solution were measured through successive extractions. Total phenolic content was determined by the Folin-Ciocalteu method, antioxidant activity was evaluated by 1,1-diphenyl-2-picrylhydrazyl-free radical scavenging assay, and the characteristics of functional groups were analyzed by Fourier transform IR spectroscopy. The formaldehyde-condensable polyphenols were estimated with the Stiasny method. Lignin and holocellulose contents were determined by gravimetric method. Results showed that the amounts of extractives soluble in the three solvents varied significantly with bark species. Lodgepole pine bark contained the highest content of hexane-soluble extractives (15.0%), and aspen bark contained a very high content of ethanol solubles (22.3%). The 1% NaOH solubles ranged from 20.5 to 35.5% of the original bark. Except balsam fir, the total phenolic contents of ethanol solubles were between 200 and 300 mg equivalent catechin per gram of extract. The ethanol-soluble extractives from lodgepole pine bark and sugar maple bark had considerably high antioxidant potential; their IC50 values were about 11 μg/mL. The barks of softwood species contained a higher amount of formaldehyde-condensable polyphenols than those of hardwood species included in this study.


ASTM (2007) D 1109-84. Standard test method for 1% sodium hydroxide solubility of wood. American Society for Testing and Materials, West Conshohocken, PA.nBorgin K, Corbett K (1974) The hydrophobic and water-repellent properties of wattle bark extractives. Wood Sci Technol 8(2):138-147.nBrowning BL (1967) Methods of wood chemistry, Vol. 2. Wiley-Interscience, New York, NY. 698 pp.nDiouf PN, Stevanovic T, Cloutier A (2009) Antioxidant properties and polyphenol contents of trembling aspen bark extracts. Wood Sci Technol 43(5-6):457-470.nD'Souza J, Yan N (2013) Producing bark-based polyols through liquefaction: Effect of liquefaction temperature. ACS Sustainable Chemistry & Engineerin 1(5):534-540.nEffland MJ (1977) Modified procedure to determine acid-insoluble lignin in wood and pulp. Tappi J 60(10): 143-144.nFengel D, Wegener G (eds.) (1984) Bark constituents. In Wood chemistry ultrastructure reactions. Walter de Gruyter, Berlin, Germany. 613 pp.nGarro Galvez JM, Riedl B, Conner AH (1997) Analytical studies on tara tannins. Holzforschung 51:235-243.nHarkin JM, Rowe JW (1971) Bark and its possible uses. Res note FPL-091. USDA For Serv Forest Prod Lab, Madison, WI. 56 pp.nHillis WE (1987) Heartwood and tree exudates. Springer-Verlag, Berlin, Germany. 268 pp.nHuang Z, Hashida K, Makino R, Kawamura F, Shimizu K, Kondo R, Ohara S (2009) Evaluation of biologica activities of extracts from 22 African tropical wood species. J Wood Sci 55(3):225-229.nKiefer HJ, Kurth EF (1953) The chemical composition of bast fibers of Douglas-fir bark. Tappi J 36:14-19.nKofujita H, Ettyu K, Ota M (1999) Characterization of the major components in bark from five Japanese tree species for chemical utilization. Wood Sci Technol 33:223-228.nKu CS, Mun SP (2007) Characterization of proanthocyanidin in hot water extract isolated from Pinus radiata bark. Wood Sci Technol 41(3):235-247.nKurth EF (1947) The chemical composition of barks. Chem Rev 40(1):33-49.nMiyazaki J, Hirabayashi Y (2010) Effect of the addition of Acacia mangium bark on thermosetting of phenol-formaldehyde resin. Wood Sci Technol 45(3):449-460.nNgueho Yemele MC, Koubaa A, Diouf PN, Blanchet P, Cloutier A, Stevanovic T (2008) Effects of hot-water treatment of black spruce and trembling aspen bark raw material on the physical and mechanical properties of bark particleboard. Wood Fiber Sci 40:339-351.nOna T, Sonoda T, Shibata M, Fukazawa K (1995) Small-scale method to determine the content of wood components from multiple eucalypt samples. Tappi J 78(3): 121-126.nPakdel H, Murwanashyaka JN, Roy C (2002) Extraction of betulin by vacuum pyrolysis of birch bark. J Wood Chem Technol 22(2-3):147-155.nPuls J (1993) Substrate analysis of forest and agricultural wastes. Pages 65-78 in Saddler JN (ed.). Bioconversion of forest and agricultural plant residues. CAB International, Wallingford, UK.nRoss J, Gagnon H, Girard D, Hachey J-M (1996) Chemical composition of the bark oil of balsam fir Abies balsamea (L.) Mill. J Essent Oil Res 8(4):343-346.nSilverstein RM, Bassler GC, Morrill TC (1981) Spectrometric identification of organic compounds. John Wiley and Sons, New York, NY. 442 pp.nSofowora A (1996) Research on medicinal plants and traditional medicine in Africa. J Altern Complement Med 2(3):365-372.nSweet HR, Fetrow RH (1975) Ground-water pollution by wood waste disposal. Ground Water 13(2):227-231.nTroughton GE (1995) Literature review of worldwide research reports on bark utilization. A free report from Department of Economic Development and Tourism, Forest Industry Development, Edmonton, Alberta, Canada.nVazquez G, Antorrena G, Parajo JC, Francisco JL (1989) Preparation of wood adhesives by polycondensation of phenolic acids from Pinus pinaster bark with resoles. Holz Roh Werkst 47:491-494.nVazquez G, Gonzalez-Alvarez J, Freire S, Lopez-Suevos F, Antorrena G (2001) Characteristics of Pinus pinaster bark extracts obtained under various extraction conditions. Holz Roh Werkst 59(6):451-456.nYazaki Y, Hillis WE (1977) Polyphenolic extractives of Pinus radiata bark. Holzforschung 31(1):20-25.nYuan T, Wan C, Gonzalez-Sarrias A, Kandhi V, Cech NB, Seeram NP (2011) Phenolic glycosides from sugar maple (Acer saccharum) bark. J Nat Prod 74:2472-2476.nZhao Y, Yan N, Feng M (2010) Characterization of phenol formaldehyde resins derived from liquefied lodgepole pine barks. Int J Adhes Adhes 30(8):689-695.nZhao Y, Yan N, Feng M (2012) Polyurethane foams derived from liquefied mountain pine beetle-infested barks. J Appl Polym Sci 123(5):2849-2858.nZhao Y, Yan N, Feng M (2013) Bark extractives-based phenol-formaldehyde resins from beetle-infested lodgepole pine. J Adhes Sci Technol 27(18-19):2112-2126.n






Research Contributions