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Lignocellulose is resistant to degradation and requires pretreatment before hydrolytic enzymes can release fermentable sugars. Sulfuric acid has been widely used for biomass pretreatment, but high amount of degradation products usually occurred when using this method. To enhance accessibility to cellulose, we studied the performances of several dilute organic acid pretreatments of sugarcane bagasse and oil palm empty fruit bunch fiber. The results revealed that pretreatment with maleic acid yields the highest xylose and glucose release among other organic acids. The effects of concentration, duration of heating and heating temperature were further studied. Dilute maleic acid 1 % (w/w) pretreatment at 180 °C was the key to its viability as a substitute for sulfuric acid. Moreover, maleic acid did not seem to highly promote the formation of either furfural or 5-HMF in the liquid hydrolysate after pretreatment.

Each year, the palm oil industry generates a significant amount of biomass residue and effluent waste; both have been identified as significant sources of greenhouse gas (GHG) emissions. This issue poses a severe environmental challenge for the industry due to the possibility of long-term negative effects on human well-being. The palm-oil industry must invest significantly in the technology that is required to resolve these issues and to increase the industry's sustainability. However, current technologies for converting wastes such as lignocellulosic components and effluents into biochemical products are insufficient for optimal utilization. This review discusses the geographical availability of palm-oil biomass, its current utilization routes, and then recommends the development of technology for converting palm-oil biomass into value-added products through an integrated biorefinery strategy. Additionally, this review summarizes the palm oil industry's contribution to achieving sustainable development goals (SDGs) through a circular bioeconomy concept.

Production of bioplastics from renewable biological resources is a prerequisite for the development of a circular and sustainable society. Current bioplastics are mostly heat‐sensitive aliphatic polymers, requiring thermoresistant aromatic bioplastics. Herein, 3‐amino‐4‐hydroxybenzoic acid (AHBA) and 4‐aminobenzoic acid (ABA) are produced from kraft pulp, an inedible cellulosic feedstock, using metabolically engineered bacteria. AHBA is chemically converted to 3,4‐diaminobenzoic acid (DABA); subsequently, poly(2,5‐benzimidazole) is obtained by the polycondensation of DABA and processed into an ultrahigh thermoresistant film. The copolymerization of DABA with a small amount of ABA dramatically increases the degradation temperatures of the resulting films (over 740 °C) to yield the most thermoresistant plastic on record. Density functional theory calculations indicate that the incorporation of ABA strengthens the interchain hydrogen bonds between aromatic imidazole rings. Thus, an alternative organic molecular design is proposed for thermoresistant plastics without using heavy inorganics, although continuous aromatic heterocycles are widely considered ideal for polymer thermoresistance. This innovative macromolecular design increases thermoresistance and can be widely applied to well‐processable plastics for the production of lightweight materials and is expected to contribute to the development of a more sustainable society.

Kraft pulping of sweet sorghum bagasse (SSB) has been used for effective delignification method for cellulose production. This study was conducted to evaluate the performance pulp kraft of SSB for reducing sugar production. The study intended to investigate the effect of active alkali and sulfidity loading variation of SSB pulp kraft on reducing sugar yield per biomass. The SSB pulp was prepared after pulping using three variations of active alkali (17, 19, and 22%) and sulfidity loading (20, 22, and 24%) at 170°C for 4 h with liquor to wood ratio of 10. A total of 9 pulps were obtained from these pretreatments. Delignification pretreatment has been succesfully removed lignin and hemicellulose more than 90% and 50%, respectively. Increasing active alkali and sulfidity loading has significantly increased lignin removal caused by disruption of the cell wall structure for releasing lignin into black liquor in the cellulose extraction. The enzymatic hydrolysis of pulp was carried out with cellulase loading of 40 FPU per g substrate in the shaking incubator at 50°C and 150 rpm for 78 h. For each 24 h, the reducing sugar yield (DNS assay) has been observed. Even though the lignin and hemicellulose loss occurred along with higher active alkali loading, this condition tends to decrease its yield. The reducing sugar concentration varied between 7-8 g/L. Increasing active alkali and sulfidity was significantly decreased the reducing sugar per biomass. Pulp delignified by 17% active alkali and 20% sulfidity has demonstrated the maximum reducing sugar yield per biomass of 45.57% resulted after 72 h enzymatic hydrolysis. These results indicated that kraft pulping was success to degrade more lignin and hemicellulose content to facilitate the enzyme for breaking down the cellulose into its sugar monomer. A high loss of lignin and hemicellulose are not single factor to improve digestibility of SSB. This sugar has potential for yeast fermented into bioethanol.