| dc.description.abstract | Reaction wood is a wood xylem formed as a respons of tree to external forces. Reaction wood has different chemical characteristics compared with normal wood. This research aimed to examine the variation of lignin contents at different positions in the reaction wood of Api-api (Avicennia sp.), and lignin solubility in alkali cooking. Klason lignin and acid-soluble lignin contents were determined using Klason method and UV-spectrophometry. Cooking experiment was carried out in 20% alkali solution at 150 C for 45 min. Klason lignin content varied between samples position was 15.03-20.8%, and acid-soluble lignin content was 3.06-4.29%. Wood samples derived from severest reaction wood part tend to have lowest Klason lignin content and highest acid-soluble lignin content. The lignin solubility of Api-api wood in the alkaline cooking at 150 C for 45 min was 46.13-54.47%. Although the statistical test was not significant, however, the lignin Avicennia sp. wood was relatively easy to be delignified in alkali cooking. | id |
