Article Per Year (5 Year)
p-Index From 2020 - 2025
0.23
P-Index
This Author published in this journals
All Journal Jurnal Penelitian Pendidikan IPA (JPPIPA) Acta Chimica Asiana
Lalu Rudyat Telly Savalas
University of Mataram
Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Education Materials Science & Nanotechnology Physics

Published : 2 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search

 1 
Theoretical study on the binding selectivity of 18-membered azacrown ethers with alkaline earth metal species Saprini Hamdiani; Lalu Rudyat Telly Savalas; Agus Abhi Purwoko; Saprizal Hadisaputra
Acta Chimica Asiana Vol. 1 No. 1 (2018)
Publisher : Chemistry Education Program, the University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (859.878 KB) | DOI: 10.29303/aca.v1i1.5

Abstract

The binding selectivity of 18-membered azacrown ethers (monoaza- N1, diaza- N2, triaza- N3, tetraaza- N4, pentaaza- N5, and hexaaza-18-crown-6 N6) with Ca2+, Sr2+, Ba2+ have been studied by density functional theory (DFT) calculations. The complex binding selectivity was analyzed in term of interaction energies, thermodynamic properties, second order interaction energies, and charge transfer effects. The geometrical study shows that Ca2+ and azacrown complexes acquire envelope like structure, leading to shorter bond lengths. As a result, these complex systems have the highest interaction energies. Theoretical study also showed that N6 complex with alkaline earth metal ion were shown to be more stable complex than those ligand with lower nitrogen number. The interaction energy order is N0 < N1 < N2 < N3 < N4 < N5 < N6. This trend shows that the presence of more nitrogen on the crown ether cavity increases the interaction energies by approx. 7.3 % in going from N0 to N6. It is clearly showed that the contribution of the number of nitrogen play a dominant role in the binding selectivity of these systems.
Isolation of Lipase from Candlenut Seeds and Its Immobilization in Polyacrylamide Gel Zella Yaumin Nasry; Nyoman Maya Krisnawati; Erin Ryantin Gunawan; Jannatin ‘Ardhuha; Agus Abhi Purwoko; Lalu Rudyat Telly Savalas
Jurnal Penelitian Pendidikan IPA Vol. 8 No. 3 (2022): July
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v8i3.1483

Abstract

In general, lipase enzymes are used in the form of free lipase enzymes which can only be used once and are less effective, so that their use is costly. Therefore, to maximize the use of the lipase enzyme, immobilization of the enzyme that allows multiple use is a choice. The purpose of this study was to determine the activity of the candlenut (Aleurites moluccana (L.) Wild) lipase in its free form and in immobilization form. The stability of the immobilized lipase enzyme with repeated use was also investigated. The enzyme was immobilized by trapping method using polyacrylamide gel. The immobilized lipase enzyme was characterized to determine its stability after repeated use with various gel concentrations. The crude extract of the lipase of candlenut seed sprouts had an activity of 2.32 U/mL, whereas the activity of the immobilized lipase enzyme in polyacrylamide gel at concentrations of 6%, 8%, and 10%, were 2.133; 2,259; and 2,311 U/mL, respectively. The optimum temperature for the immobilized lipase enzyme was 30 oC and the optimum pH was 7.5. After five time us usage, the immobilized enzyme showed activities of 49.49%, 72.60% and 86.53%, for 6%, 8% and 10% polyacrylamide gel, respectively. These results indicate that the immobilized lipase enzyme from seed sprouts of candlenut (Aleurites moluccana (L.) Wild) by trapping method using 10% polyacrylamide gel can maintain its stability after five times of use
Co-Authors Agus Abhi Purwoko Erin Ryantin Gunawan Jannatin ‘Ardhuha Nyoman Maya Krisnawati Saprini Hamdiani Saprizal Hadisaputra Zella Yaumin Nasry