Ethanolic fermentation using Saccharomyces cerevisiae was carried out on three types of hydrolysates produced from lignocelulosic biomass which are commonly found in Malaysia such as oil palm trunk, rubberwood and mixed hardwood. The effect of fermentation temperature and pH of hydrolysate was evaluated to optimize the fermentation efficiency which defined as maximum ethanol yield in minimum fermentation time. The fermentation process using different temperature of 25 degrees Celsius, 30 degrees Celsius and 40 degrees Celsius were performed on the prepared fermentation medium adjusted to pH 4, pH 6 and pH 7, respectively. Results showed that the fermentation time was significantly reduced with the increase of temperature but an adverse reduction in ethanol yield was observed using temperature of 40 degrees Celsius. As the pH of hydrolysate became more acidic, the ethanol yield increased. Optimum fermentation efficiency for ethanolic fermentation of lignocellulosic hydrolysates using S. cerevisiae can be obtained using 33.2 degrees Celsius and pH 5.3.

Disposing of solid waste and demand of fossil fuel have become the great challenges in the 21st century. Malaysia as one of the top producers of palm oil and wooden furniture in the world is well positioned to take the challenge of the reuses of its enormous output of lignocellulosic biomass such as oil palm trunk, sawdust of rubberwood and sawdust of mixed hardwood generated from palm oil and furniture industries. Before these lignocellulosic biomasses can be used to produce fuel and major chemicals which are normally derived from petroleum, lignocellulosic materials have to be converted to glucose. Hence, it is a need to investigate the conversion efficiency and to determine the optimum conditions for the conversion of lignocellulosic materials to glucose. This present work is aimed to investigate the potential use of oil palm trunk, rubberwood sawdust and mixed hardwood sawdust as an alternative feedstock for lignocellulosic glucose production. This research also served to identify the optimum two-stage concentrated acid hydrolysis condition that can convert these three lignocellulosic biomasses to glucose efficiently. Two stages concentrated sulfuric acid hydrolysis process using different acid concentration and reaction time were performed on those lignocellulosic biomass samples. The optimum results for oil palm trunk, rubberwood and mixed hardwood sawdust were obtained by using 60% acid concentration reacted for 30 min during 1st stage hydrolysis and subsequently followed by another 60 min reaction time with 30% acid concentration during the 2nd stage hydrolysis. The results, showed that oil palm trunk has a higher glucose conversion yield than those of rubberwood sawdust and mixed hardwood sawdust.

Large area of oil palm plantation in Malaysia generated significant amount of oil palm biomass such as oil palm trunk. This material is assumed to possess multipurpose utilization, including a starch-producing raw material. This work is aimed to determine the total extractable starch from oil palm trunk (OPT) using commercial steeping methods. The extraction methods used in this study include steeping the OPT in sodium metabisulphite (Na2S2O5) alone and with the addition of lactic acid (C3H6O3). The effect of process parameters: incubation temperature (IT) (room temperature at 26 °C, 40 °C, 50 °C), incubation period (IP) (24 h, 36 h, 48 h) and substrate mesh size (MS) (20 mesh, 40 mesh, 60 mesh) were evaluated for their effect on starch yield. The experimental results indicated that with the addition of lactic acid during steeping improved the starch yield (3.61%) as compared to that of steeping using sodium metabisulphite alone (0.92%). The effect of substrate mesh size is more significant than process parameters: incubation temperature and incubation period on the starch yield. The contour plot was derived from the equation and applied to determine the interactive effects of IT × IP, IT × MS and IP × MS. Among the interactions, IT × MS is more significant than IT × IP, and IP × MS on the starch yield. A second-order regression equation was developed for the response as a function of independent coded parameters (R2 = 0.91). Conclusively, starch recovery increased with increase of OPT mesh size and steeping incubation temperature.

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Termites thrive in great abundance in terrestrial ecosystems and the symbiotic gut microbiota play important roles in digestion of lignocelluloses and nitrogen metabolism. Termites are excellent models of biocatalysts as they inhabit dense microbes in their guts that produce digestive enzymes to decompose lignocelluloses and convert it to end products such as sugars, hydrogen, and acetate. Different of digestive system between lower and higher termites which lower termites dependent on their dual decomposing system, consisting of termite's own cellulases and gut's protists. Higher termites decompose cellulose using their own enzymes, because of the absence of symbiotic protists. Termite gut prokaryotes efficiently support lignocelluloses degradation. In this review, a brief overview of recent experimental works, development and commercialization is discussed. Significant progress has been made to isolate cellulolytic strains from termites and optimise the digestion efficiency of cellulose. Future perspective should emphasize the isolation of cellulolytic strains from termites, genetically modifying or immobilization of the microbes which produce the desired enzyme and thus benefits on the microbiology and biotechnology.