فهرست مطالب rokiah hashim

The main objectives of this study were to evaluate the biodegradation behaviour of experimental particleboard bonded with modified 30 % of PVOH, 70 % of Oil palm starch and 3 % of nano silicon dioxide (SiO2). Boric acid at 2 % was also added as a cross-linker to PVOH in modified oil palm starch to enhance decay resistant for the samples. All the particleboards were evaluated by soil burial, borer and fungal strains tests. The samples were then compared with particleboard bonded with native oil palm starch and commercial urea formaldehyde (UF). The results indicated that particleboards bonded with modified PVOH/Oil palm starch were more resistant than particleboard bonded with their native starch and thus can be used as a potential binder for green particleboard in future. The SiO2 also showed a significant effect towards modified oil palm starch as compared to their native oil palm starch and commercial binder.

Oil palm trunk particleboard without synthetic adhesive has been introduced as one of the potential green technology products as an alternative to the synthetic resin bonded particleboard. The chemical constituents of the lignocellulosic materials are important in allowing particles to achieve self bonding. The main objective of this study was to evaluate the influence of starch content on the physical and mechanical properties, as well as some biodegradation activities including termite decay and soil burial decay of the particleboard without synthetic adhesive. Internal bonding strength, modulus of rupture, thickness swelling, and soil burial were performed according to British Standard and European Standard. The termite decay on specimen was evaluated with Microtermes gilvus. Addition of starch into specimens resulted in adverse effect on thickness swelling but improved mechanical properties of the samples. However, removing starch containing in particles showed insignificant effect on mechanical properties of the specimens. Weight loss of specimens exposed to termites was not affected by starch content statistically. However, soil buried test samples had significant weight loss.

The study was done to investigate the antioxidant, total phenol content and antifungal characteristics of phenolics compounds of extracts from Cinnamomum iners (Reinw. ex Blume-Lauraceae) wood. Radical scavenging activity method of DPPH was used to determine antioxidant activity of the extracts. Four fungus, namely white fungi (Pycnoporus sanguineus, Trametes versicolor, Fomitopsis palustris) and brown fungi (Gleophyllum trabeum) were used to determine the antifungal activity of the Cinnamomum iners extracts. The results showed that ethanol extract had the highest antioxidant activity with EC50 value of 14.96 μg/mL followed by chloroform extract with EC50 >30 μg/mL while water extract did not show any significant antioxidant activity. For total phenolics content, ethanol extract resulted on the highest value of 56.23%, followed by chloroform extract and water extract having total phenolic values of 51.13% and 7% respectively. On the other hand for antifungal assay, ethanol extract produce the widest inhibition zone followed by chloroform extract and water extract respectively.

Pycnoporus sanguineus is a white rot fungus that is known for selective and destructive wood bio delignification in tropical forests. This filamentous fungus is harvested on oil palm biomass (OPB) under solid substrate fermentation (SSF) and produces white-rot decay by generating ligninolytic enzyme Laccase (Lac). Laccase is produced at room temperature in the presence of Kirk’smedia supplemented with glucose, ammonium nitrate and corn steep liquor. The Lac enzymes are able to endure temperatures ranging from 10 to 700C and also the pH variation from 2.5-6. The synthesis of this enzyme, accountable for lignin degradation in oil palm biomass can further be exploited to degrade the unmanageable organic contaminants in the atmosphere. It is observed that selective lignin degradation was produced by P.sanguineus for time period of 4 weeks. The weight and component losses of oil palm trunk chips after decay were evaluated and analyzed by Scanning Electron Microscope. The maximum Laccase activity was 1007. 8 U/L on the 10th day of incubation. The present work is dedicated to assess the biodegradation of oil palm biomass and study for its pretreatment of enzyme activity.