Abstract: The toxic effects of selected Malaysian timbers (Madhuca utilis, Anisoptera laevis and Endospermum malaccense) heartwood extracts were studied with the aim to determine and understanding the function of wood extracts as a natural protection against termite. The results show that no-choice experiments revealed toxic properties of all investigated extracts by the contact against Coptotermes gestroi and Coptotermes curvignathus. However, high termite mortality was only achieved with Madhuca utilis extracts and methanol solvents.

ABSTRACT The effects of four different types of bleaching agents (hydrogen peroxide, sodium hypochlorite, sodium chlorite and oxalic acid) mixed together with 2% boron-based preservative (Celbor SP) were studied on green sawn rubberwood. Two concentration levels (1% and 2%) of were used. Whitish values (W) and colour changes (ΔE) of sawn rubberwood were assessed before and after chemical treatment using a colour meter. Preliminary observation indicated that timber treated with 1% and 2% hydrogen peroxide produced better and more homogeneous colour properties. Hydrogen peroxide treated timber gave higher whitish values (6.23 and 9.91 for 1% and 2% solution, respectively) and lower colour changes (8.49 and 5.51 for 1% and 2% solution, respectively) when compared to the other three chemicals. Evaluation on the effects of bleaching (hydrogen peroxide with a higher level of concentration) on physical, mechanical and biological properties of rubberwood also have been determined in this study.

Extratos de madeira de cerne de Calophyllum inophyllum (bintangor) foram obtidos pelo método de agitação e os seus componentes analisados por cromatografia em fase gasosa-espectrometria de massa (GC-MS). Dez compostos foram identificados pelo emprego de solvente etanol (EtOH), e catorze por metanol (MeOH) e apenas nove por éter de petróleo (PETETHR). Os principais compostos dessas frações foram identificados como monoterpenos (75,11%, 53,75%), quando extraídos com os solventes EtOH e PETETHR. O ensaio anti-cupins dos extratos da madeira também foram investigados contra Coptotermes curvignathus. O nível de concentração necessário para a atividade anti-fungica pode ser uma indicação da dose de aplicação dos extratos de madeira para o novo experimento da ação termiticida.

Wood extractives from heartwood of Callophylum inophyllum (bintangor) were obtained by shaker method and analyzed for their constituents by gas chromatography-mass spectrometry (GC-MS). Ten compounds were identified by ethanol (EtOH) solvents, fourteen by methanol (MeOH) and only nine by petroleum ether (PETETHR). Major compounds were contributed by monoterpenes (75.11%, 53.75%) when extracted with EtOH and PETETHR solvents. The anti-termitic assay of the wood extracts was also investigated against Coptotermes curvignathus. The level of concentration for anti-termite activity may be an indication of the dose application of the wood extracts for new development of termiticide.