Glucose oxidase from Aspergillus niger IPBCC.08.610 (GOD_IPBCC) is a locally sourced flavoenzyme from Indonesia that can potentially be developed in a variety of industrial processes. Although this enzyme has a high activity in catalyzing the redox reactions, the use of this enzyme was still limited to be applied as glucose biosensor. Using information from the amino acid sequences, a computational structure of GOD_IPBCC was therefore designed by homology modeling method using two homologous structures of GOD from protein data bank (1CF3 and 5NIT) as the templates. The quality of the resulting structures was evaluated geometrically for selection of the best model, and subsequently, 50 ns of MD simulations were carried out for the selected model as well as the corresponding template. Results obtained from the validation analysis showed that the 1CF3 template-built structure was selected as the best reliable model. The structural comparison exhibited that the best-modeled structure consisted of two functional domains and three catalytic residues similarly to the corresponding experimental structure. The overall dynamic behavior of the 50 ns of the structure was structurally stable and comparable with that of the positive control both from globally and locally observations. Implications of these stable nature within the best-modeled structure unfold the possibilities in search of notable residues and their roles to enhance enzyme thermostability.

L-asparaginase merupakan enzim yang menghidrolisis L-asparagin menjadi L-aspartat dan ammonia yang dapat digunakan dalam terapi pengobatan Leukemia Limfoblastik Akut. Penentuan struktur 3D L-asparaginase dari berbagai sumber dapat memberikan informasi penting dalam memahami sifat dan fungsi biokimia L-asparaginase di level molekuler untuk penelusuran L-asparaginase alternatif sebagai protein teurapetik. Tujuan penelitian ini adalah memprediksi struktur 3D enzim L-asparaginase II dari bakteri laut Vibrio sp. AND4 dengan E.coli L-asparaginase II mutant (T12V) in complex with L-Asn at pH 7.0 [Escherichia coli K-12] (PDB ID: 6PA9) sebagai templat struktur, menggunakan metode pemodelan homologi dengan program SWISS-MODEL. Penelitian ini menghasilkan model struktur 3D dengan Sequence identity 70,55%, memiliki nilai QMEANDisCo 0,86±0,05 dan nilai GMQE sebesar 0,86. Terdapat 93,1% residu berada di daerah the most favored regions dan 0,3% residu berada di daerah disallowed regions pada Ramachandran plot, dengan G-Factors sebesar -0.08 yang memenuhi syarat-syarat kualitas struktur ideal.

Cinnamon (Cinnamomum burmannii) is an herbal plant that has a function, one of which is lowering glucose in the blood and warding off free radicals that cause oxidative stress. This study aims to determine the inhibitory activity of the enzyme compound α-glucosidase and the suppression of DPPH free radicals using the first, second, and third replications of cinnamon bark water extract (C. burmannii) as a natural source of antidiabetic drug candidates. The extraction method uses the infundation technique and is carried out using a spectronometer. The highest yield was obtained in the extraction of the first repeat, which is with an average of 0.674%, the yield did not differ markedly (p>0.05) with the second and third repeats. The highest results of total phenolic testing were obtained in the second repeat extraction of 100.374 GAE g-1, the results differed markedly (p<0.05) with the first and third repeats. The highest results of testing antioxidant activity were obtained at the extraction of the first repeat which was 9.012 mg of AAE g-1, the results differed markedly (p<0.05) with the second and third repeats. The highest result of testing of enzyme inhibition activity α-glucosidase was found in the extraction of the first repeat which was 99.650%, the results did not differ markedly (p>0.05) with the second and third repeats.