Evaluation of the characteristics of Eucalyptus pellita and acacia hybrid superior clones selected from breeding program in Indonesia as materials for pulp and papermaking

This study evaluates the characteristics of superior clones of Eucalyptus pellita and Acacia hybrid (Acacia mangium × A. auriculiformis) aged six years selected from a breeding program in Indonesia as materials for pulp and papermaking. Height, diameter, and wood density differed significantly between species and among the clones, with respective mean values 21.6 m, 12.57 cm, and 657 kg.m-3 for E. pellita and 19.5 m, 24.83 cm, and 567 kg.m-3 for Acacia hybrid. Most fiber morphologies were significantly different between species. Cellulose and lignin differed significantly only among Acacia hybrid clones. The mean value of screened pulp yield Acacia hybrid (52.50%) was higher than that of E. pellita (50.31%). Kappa number and brightness were significantly different between species and among E. pellita clones. Some correlations of growth and wood properties showed a better relationship to pulp properties. Handsheet properties varied between species, and some clones showed an outstanding one.

The contents of phenolics and cell wall component of Eucalyptus pellita F. Muell stemwood and bark

Eucalyptus pellita is the fast-growing species which is being developed for a raw material of pulp and paper in Indonesia. The aim of this research was to evaluate the total phenolics (TPC) and flavanols contents (TFC) in the stemwood and bark parts from four individual trees. Another purpose was to determine its cell wall contents. Wood and bark materials in two vertical positions (bottom and top) were successively extracted using dichloromethane, ethanol and hot water as the solvents. Axial factor affected significantly in the values of hot water extract, TPC, and TFC but no significantly affected the cell wall component contents. The ethanol extract levels in the heartwood part was the significantly highest. It is noticed that the heartwood part had high levels of the TPC and TFC and low level in lignin content. From this experiment, the comparatively high levels of TPC and TFC in the heartwood indicate the potential antioxidative properties that should be explored in the future. Further, the low content of Klason lignin in the heartwood part would be an advantage for pulp production.