Oil palm residue biodelignification by bacillus cereus ligninase from coptotermus curvignathus gut for handsheet production

• Main Author: S, Sharfina Mutia Syarifah
• Format: Thesis
• Language: English; English; English
• Published: 2020
• Subjects: QP501-801 Animal biochemistry
• Online Access: http://eprints.uthm.edu.my/1071/1/24p%20SHARFINA%20MUTIA%20SYARIFAH.pdf; http://eprints.uthm.edu.my/1071/2/SHARFINA%20MUTIA%20SYARIFAH%20COPYRIGHT%20DECLARATION.pdf; http://eprints.uthm.edu.my/1071/3/SHARFINA%20MUTIA%20SYARIFAH%20WATERMARK.pdf; http://eprints.uthm.edu.my/1071/
• Institution: Universiti Tun Hussein Onn Malaysia

Conventional methods used to delignify lignin using mechanical and chemical process consumed high energy and environmentally unfriendly. Meanwhile, the demand for paper substantially increased with declined wood fibres. In this study, Bacillus cereus isolated from termite species Coptotermes curvignathus gut’s bacteria was tested for biodelignification capability on palm oil biomasses: oil palm leaves (OPL), oil palm trunk (OPT) and empty fruit bunch (EFB). The biopulp was produced under submerged fermentation (SmF) using Luria Bertani (LB) broth at pH 6.5, 120 rpm and 37 °C for 7 days. The enzyme expression was partially characterized and protein sequenced. There were 11 enzymes responsible for lignin degradation such as 4-aminobutyrate aminotransferase (GABA), serine hydrolase, amidohydrolase, chemotaxis protein, GMC family protein, glycosyltransferase, heme peroxidase, phosphate binding protein PstS, ABC transporter ATP-binding protein, nitrate reductase, and nitrite reductase. The delignification ability was tested on its chemical composition. Methods used followed technical association pulp and paper industry TAPPI T 222 om-02 (lignin content), Kurscher-Hoffner (holocellulose and hemicellulose content) and Chlorite (cellulose content). The highest lignin reduction was 21.7% for treated EFB followed by OPT (7.0%) and OPL (9.2%). EFB showed highest reduction (76.9%) for scanning electron microscope (SEM) and imageJ analysis and lowest gap average area (0.03 mm2) compared with untreated OPL which were 26.3% and 1.63 mm2, respectively. The treated biopulps were ground using refiner mechanical pulping (RMP) and proceeded handsheet making according to technical association pulp and paper industry (TAPPI) standard methods. Treated EFB performed best in mechanical properties with higher tensile index (7.15 Nm/g), tearing index (1.69 mN.m2/g) and bursting index (0.35 kPa.m2/g) which supports paper strength with fixed grammage and thickness value. This concludes that Bacillus cereus delignification on EFB sample is the finest pair for handsheet production. This research proposed an alternative biopulping process on oil palm residues handsheets.