Literature has shown that oil palm leaves (OPL) can be transformed into nanocellulose (NC) by fungal lignocellulosic enzymes, particularly those produced by the Trichoderma species. However, mechanism of β-glucosidase and xylanase selectivity to degrade lignin, hemicellulose and cellulose in OPL for NC production remains relatively vague. The study aimed to comprehend this aspect by an in silico approach of molecular docking, molecular dynamics (MD) simulation and Molecular-mechanics Poisson-Boltzmann surface area (MM-PBSA) analysis, to compare interactions between the β-glucosidaseand xylanase from Trichoderma asperellum UC1 in complex with each substrate. Molecular docking of the enzyme-substrate complex showed residues Glu165-Asp226-Glu423 and Arg155-Glu210-Ser160 being the likely catalytic residues of β-glucosidase and xylanase, respectively. The binding affinity of β-glucosidase for the substrates are as follows: cellulose (−8.1 kcal mol ) > lignin (−7.9 kcal mol ) > hemicellulose (−7.8 kcal mol ), whereas, xylanase showed a corresponding preference for; hemicellulose (−6.7 kcal mol ) > cellulose (−5.8 kcal mol ) > lignin (−5.7 kcal mol ). Selectivity of both enzymes was reiterated by MD simulations where interactions between β-glucosidasecellulose and xylanase-hemicellulose were the strongest. Notably low free-binding energy (ΔG ) of β-glucosidase

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Students are the next generation of leaders to govern the country. However, many pressures affect their performance and life at university such as academic and social pressures. These pressures can sometimes cause stress among students. Having suicidal thoughts, drugs addiction, and dropping out of college are some of the situations that might be caused by pressures and stress among students. Among all types of stress faced by students, academic stress is one of the reasons why some students fall into deeper problems such as depression and anxiety. Academic stress can come from various reasons such as lecturers, assignments, peers and much more. Thus, this paper aims to identify the academic stress level among students in Universiti Teknologi Malaysia (UTM). 100 students has been involved in this study which require them to answer a survey regarding sources of stress. The result from the survey is analyzed to determine the level of stress according to each source of stress. This study found that students mostly suffer from high academic stress due to results, tests, peers and self-inflicted stress. The results from this study will enable students, educators and universities to observe and take action on how to help students who suffer from academic stress during their study and for future research to further explore in this issue.

Currently, the catalytic residue of the highly prolific fungal β-glucosidase (BGL) of Trichoderma asperellum UC1 remains unvalidated.  The study used the alanine scanning method to confirm the catalytic residues of the BGL as Glu165, Asp226, and Glu423. This method cancels out all intermolecular hydrogen bonds with substrates, lignin, hemicellulose, and cellulose. Results revealed an overall decline in the stability of the energy-minimized mutant enzymes' compared to the wild-type BGL. The mutant enzyme registered lower PROCHECK (91.0%), ERRAT (93.09%), and Verify-3D (98.92%) values, in comparison to 90.2%, 92.09%, 98.06%, in the wild-type BGL, respectively. The mutant BGL UC1-substrate complexes were less stable than the wild-type enzyme, in which the mutant exhibited higher binding energies for docked lignin (−7.4% kcal mol-1), cellulose (−7.2 kcal mol-1), and hemicellulose (−7.2 kcal mol-1). Binding energies of the wild-type BGL with the corresponding substrates were lower at −7.9 kcal mol-1, −8.1 kcal mol-1, and −7.8 kcal mol-1. An interesting observation was that the alanine scanning changed the substrate preference order based on the calculated binding energies. The mutant BGL bound preferentially to lignin>cellulose=hemicellulose, while the wild-type BGL was selective to cellulose>lignin>hemicellulose. Hence, the findings convey the high likelihood of Glu165, Asp 256, and Glu423 are the catalytic residues of the BGL of T. asperellum UC1.