The chemical compositions of cultivated 3 year-old bamboo culms of Gigantochloa brang, G. levis, G. scortechinii and G. wrayi were studied. The culms exhibited different chemical composition in extractives, α-cellulose, lignin and ash contents between the bamboo species, location in the culms and position at the nodes and internodes. The extractive content in four species ranged from 8.30 to 9.23%. The extractive content of G.brang, G.levis, G.scortechinii and G.wrayi were 8.30%, 9:23%, 8:00% and 8.62% respectively. The holocellulose content for G. levis were 85.08%, G. wrayi 84.53%, G. brang 79.94% and G. scortechinii 74.62%. The holocellulose content for the cultivated bamboo genus Gigantochloa were 74% to 85%. The α-cellulose is the chemical constituents in the holocellulose. The highest was G.brang (51.58%) followed by G. scortechinii (46.87%), G. wrayi (37.66%) and G. levis (33.80%). The lignin content ranged between 24.84 to 32.65%. The highest were obtained in G. scortechinii (32.55%), G. wrayi (30.04%), G. levis (26.50%) and lowest in G. brang (24.83%). The ash content in four species of Gigantochloa bamboo ranged between 0.88 to 2.86%. The ash content is the highest in G. scortechinii (2.83%) follow by G. levis (1.29%), G. brang (1.25%) and the lowest in G. wrayi (0.88%).

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The chemical constituents of oil-heat treated cultivated 15 years-old Acacia hybrid were investigated. The logs of A. hybrid were harvested and cut at bottom, middle and top portions and oil-heat treated using organic palm oil at temperatures of 180, 200 and 220°C for the time 30, 60 and 90 minutes. The wood samples were dried and grinded into sawdust, and air-dried again prior to the chemical analysis. Untreated samples were used as controls. The results on the analysis of the chemical contents in the oil-treated A. hybrid shows some changes occurred when treated from 180 to 220°C. The variation occurred in the chemical contents for both the sapwood and heartwood. The holocellulose Vol. 2, No. 1 International Journal of Chemistry 98contents decrease from 71.5 to 63.1% and 73.4 to 64.0% for sapwood and heartwood respectively. The cellulose contents decreased from 47.1 to 37.7% for the sapwood and 48.9 to 38.1% for heartwood. The hemicellulose content's increases from 24.4 to 25.4% in the sapwood and 24.5 to 25.9% for the heartwood. Lignin contents increased 20.8 to 24.0% for the sapwood and 22.4 to 24.9% in the heartwood for treatment temperature from 180 to 220°C.

Screening of different cultivated bamboo species to find out potential variety of bamboo is most important. Structural variations in term of anatomy, physical and strength properties of 3 year-old cultivated Gigantochloa brang, G. levis, G. scotechinii and G. wrayi were investigated for screening purposes. The culms of these bamboos were selected, harvested and processed for subsequent studies. The results show that each species exhibited differences in the anatomy, physical and strength properties. Each species has differences in the fiber characteristics which showed significant differences between species in terms of length, diameter and lumen sizes. The vascular bundle for these genera were between 4-7/4mm 2 and were dense at the outer position in the cross section of the culm having 8.5 vascular bundle/4mm 2 , middle 4.88 vascular bundle/4mm 2 and at the inner position having 3.4 vascular bundle per/4mm 2 . The vascular bundle length was between 845-1183 μm and a width of 530-759 μm. The fibre lengths were between (1745.00-2039.98 μm), diameter (17.26-22.75 μm), lumen (3.83-8.66 μm) and wall thickness (1.3 -5.31μm). The moisture content (MC) of the bamboo in green condition ranged between 73-112%, the MC is higher at internodes (95%) compared to nodes (78%). Position at inner layer has MC at 126%, middle at 83% and outer at 41%. Density increases from outer to inner layer which started from 500 kg/m 2 at inner and increased to more than 820 kg/m 2 at outer part of bamboo at 12% moisture content. The specific gravity for all species tested was about 0.69 -0.78, but the inner position is 0.58, middle 0.73 and outer positions is 0.94. Shrinkage at radial, tangential and the volumetric were at 5-9, 7-12, and 10-17% respectively for all species. Position in a higher rate of shrinkage were at inner (8.6, 13.50, 15.44%), follow by middle (6.85, 9.72, 12.57%)

The chemical, colour and strength properties of thermally modified cultivated 15-year-old Acacia hybrid were investigated. Logs of A. hybrid were harvested and cut at the bottom, middle and top sections. The wood later underwent hot oil thermal modification using palm oil at temperatures 180°C, 200°C and 220°C for 30, 60 and 90 min. Untreated wood was used as control. The hot oil thermal modification process caused some features changed in the chemical composition, colour appearances and strength properties of A. hybrid wood. Parameters such as temperatures and treatment time were closely monitored as they influence the chemical, colour and strength changes in the treated wood. Temperatures of 180°C, 200°C and 220°C, and treatment time of 1 hr, 2 hrs. and 3 hrs. were used in the study. The degradation in holocellulose, cellulose, and hemicellulose contents was recognized when acacia woods were exposed to oil thermally modified process. Holocellulose and celulose degraded with the increasing of treatment temperature and duration of heating exposure, while lignin showed the increment in content through this treatment. The colour changes in the sapwood and heartwood were measured using the Minolta Chroma-meter CR-310 and the results are presented according to the CIE L*a*b* colour coordinates system. The results show that temperature at certain treatment time enhanced and darkened the treated wood. The colour of the treated sapwood can be enhanced to match the colour of the natural A. hybrid heartwood. The strength properties of the oil heat treated A. hybrid wood decreases in values of both MOR and MOE throughout the treatment process. The decreases in values were influenced by temperature and duration of the treatment.

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