Fractional and Structural Characterization of Ball Milled and Enzyme Lignins from Oil Palm Empty Fruit Bunch Fiber


  • Run-Cang Sun
  • Laurence Mott
  • James Bolton


Oil palm empty fruit bunch fiber, lignin, polysaccharides, phenolic acids and aldehydes, molecular weight, FT-IR, <sup>13</sup>C-NMR spectroscopy


The pure milled lignin (PML), hemicellulose rich milled lignin (HRML), pure enzyme lignin (PEL), lignin rich enzyme lignin (LREL), and solubilized lignin during enzyme treatment (SLET) fractions were obtained by 90% and 50% dioxane-water extractions from 6 days' ball milled oil palm empty fruit bunch fiber and the subsequently 3 days' cellulase-treated fiber residues, respectively. The purification was performed with a two-step precipitation method instead of traditional ether precipitation. The five lignin fractions were compared using spectroscopic and degradative techniques. The pure milled lignin and pure enzyme lignin fractions showed a very low content of associated polysaccharides (2.84-2.98%), and contained a large proportion of noncondensed syringyl units with some amounts of noncondensed guaiacyl units and fewer p-hydroxyphenyl units. They are composed mainly of β-O-4 ether bonds together with small amounts of β-5 carbon-carbon linkages. The lignin fractions also appeared to be very closely associated with hydroxycinnamic acid and glucuronic acid or 4-O-methylglucuronic acid. Glucuronic acid or 4-O methylglucuronic acid and over 83% of p-coumaric acid were identified to be esterified to lignin, and over 53% of ferulic acid was found to be linked to lignin by ether bonds.


Almendros, G., A. T. Martínez, A. E. González, F. J. Gonzalez-Vila, R. Fründ, and H.-D. Lüdemann. 1992. CPMAS 13C NMR study of lignin preparations from wheat straw transformed by five lignocellulose-degrading fungi. J. Agric. Food Chem. 40:1297-1302.nBen-Ghedalia, D., and E. Yosef. 1994. Effect of isolation procedure on molecular weight distribution of wheat straw lignins. J. Agric. Food Chem. 42:649-652.nBlakeney, A. B., P. J. Harris, R. J. Henry, and B. A. Stone. 1983. A simple and rapid preparation of alditol acetates for monosaccharide analysis. Carbohydrate Res. 113:291-299.nBjörkman, A. 1956. Studies on finely divided wood. Part 1. Extraction of lignin with neutral solvents. Sven. Pappcrstidn. 59:477-485.nButa, J. G., F. Zadrazil, and G. C. Galletti. 1989. FT-IR Determination of lignin degradation in wheat straw by white rot fungus Stropharia rugosoannulata with different oxygen concentrations. J. Agric. Food Chem. 37:1382-1384.nFroass, P. M., A. J. Ragauskas, and J. E. Jiang. 1996. Chemical structure of residual lignin from kraft pulp. J. Wood Chem. Technol. 16:347-365.nGallacher, J., C. E. Snape, K. Hassan, and M. C. Jarvis. 1994. Solid-state 13C NMR study of palm trunk cell walls. J. Sci. Food Agric. 64:487-491.nHimmelsbach, D. S., and F. E. Barton II. 1980. 13C Nuclear magnetic resonance of grass lignins. J. Agric. Food Chem. 28:1203-1208.nImamura, T., T. Watanable, M. Kuwahara, and T. Koshijima. 1994. Ester linkages between lignin and glucuronic acid in lignin-carbohydrate complexes from fagus crenata. Phytochemistry 37:1165-1173.nJung, H.-J. G., and D. S. Himmelsbach. 1989. Isolation and characterization of wheat straw lignin. J. Agric. Food Chem. 37:81-87.nKamishima, H., S. Fukuoka, and R. Matsuo. 1988. Industrial utilization of oil palm by-products. Cellulose Chem. Technol. 22:449-456.nKondo, T., T. Ohshita, and T. Kyuma. 1992. Comparison of characteristic of soluble lignins from untreated and ammonia-treated wheat straw. Anim. Feed Sci. Technol. 39:253-263.nKondo, T., T. Watanabe, T. Ohshita, and T. Kyuma. 1995. Comparative characterisation of dioxane-soluble lignins released by ball milling and by sheep digestion from forage grasses. J. Sci. Food Agric. 68:383-388.nLam, T. B. T., K. Ilyama, and B. Stone. 1992. Cinnamic acid bridges between cell wall polymers in wheat and phalaris internodes. Phytochemistry 31:1179-1183.nLapierre, C., B. Monties, E. Guittet, and J. Y. Lallemand. 1984. Photosynthetically 13C-labelled poplar lignins: 13C NMR experiments. Holzforschung 38:333-342.nLawther, J. M., R. C. Sun, and W. B. Banks. 1995. Extraction, fractionation, and characterization of structural polysaccharides from wheat straw. J. Agric. Food Chem. 43:667-675.nNewby, V. K., R. M. Sablon, R. L. M. Synge, K. V. Casteel, and C. F. V. Sumere. 1980. Free and bound phenolic acids of lucerne (medicago sativa cv europe). Phytochemistry 19:651-657.nNimz, H. H., D. Robert, O. Faix, and M. Nemr. 1981. Carbon-13 NMR spectra of lignins, 8: Structural differences between lignins of hardwoods, softwoods, grasses and compression wood. Holzforschung 35:16-26.nPan, X.-Q., D. Lachenal, V. Neirinck, and D. Robert. 1994. Structure and reactivity of spruce mechanical pulp lignins: 13C-NMR spectral studies of isolated lignins. J. Wood Chem. Technol. 14:483-506.nScalbert, A., B. Monties, E. Guittet, and J. Y. Lallemand. 1986. Comparison of wheat straw lignin preparations I. Chemical and spectroscopic characterizations. Holzforschung 40:119-129.nSreekala, M. S., S. Thomas, and N. R. Neelakantan. 1996. Utilization of short oil palm empty fruit bunch fibre as a reinforcement in phenol-formaldehyde resins: Studies on mechanical properties. J. Polymer Eng. 16:265-294.nSun, R. C., J. M. Lawther, and W. B. Banks. 1995. Influence of alkaline pre-treatments on the cell wall components of wheat straw. Ind. Crops Prod. 4:127-145.nSun, R. C., J. M. Lawther, and W. B. Banks. 1996. Effects of pre-treatment temperature and alkali concentration on the composition of alkali-soluble lignins from wheat straw. J. Appl. Polym. Sci. 62:1473-1481.nSun, R. C., J. M. Lawther, and W. B. Banks. 1997a. A tentative chemical structure of wheat straw lignin. Ind. Crops Prod. 6:1-8.nSun, R. C., J. M. Lawther, and W. B. Banks. 1997b. Fractional isolation and physico-chemical characterization of alkali-soluble lignins from wheat straw. Holzforschung 51:244-250.nTanahashi, M., and T. Higuchi. 1990. Effect of the hydrophobic regions of hemicelluloses on dehydrogenative polymerization of sinapyl alcohol. Mokuzai Gakkaishi 36:424-428.nTerrón, M. C., M. L. Fidalgo, G. Almendros, and A. E. Gonzalez. 1996. Molecular characterization of alkali lignin-IM30C: A valid alternative preparation to the Björkman lignin in the analytical study of wheat straw lignin. Rapid Comm. Mass Spectr. 10:413-418.nTomimura, Y. 1992. Chemical characteristics and utilization of oil palm trunks. JARQ 25:283-288.n






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