The Characteristic Changes of Betung Bamboo (Dendrocalamus asper) Pretreated by Fungal Pretreatment

The fungal pretreatment effect on chemical structural and morphological changes of betung bamboo was evaluated based on its biomass components after being cultivated by white rot fungi, Trametes versicolor. Betung bamboo powder (15 g) was exposed to liquid inoculum of white rot fungi and incubated at 27 degrees C for 15, 30 and 45 days. The treated samples were then characterized by FT-IR spectroscopy, X-Ray diffraction and SEM-EDS analyses. Cultivation for 30 days with 5 and 10% loadings retained greater selectivity compared to that of the other treatments. FTIR spectra demonstrated that the fungus changed the chemical structure of pretreated bambooo indicated by the decreasing of functional group intensities without changing the functional groups. The decrease in intensity at wave number of 1246 cm(-1) (guaiacyl of lignin) was greater than that at wave number of 1328 cm(-1) (deformation combination of syringyl and xylan) after fungal treatment. X-ray analysis showed the pretreated samples had a higher crystallinity than the untreated ones which might be due to the cleavage of amorphous fractions of cellulose. The pretreated bamboo have more fragile than the untreated ones confirmed by SEM. Crystalline allomorph, I-beta (monoclinic) has transformed I alpha (triclinic) structure in the pretreated bamboo for 30 days.