Optimasi Produksi Urease Oleh Bakteri Ureolitik Mud Volcano Dan Aplikasinya Pada Perbaikan Keretakan Beton Menggunakan Response Surface Methodology (Rsm)

Afriliona, Fellycita Kartika (2023) Optimasi Produksi Urease Oleh Bakteri Ureolitik Mud Volcano Dan Aplikasinya Pada Perbaikan Keretakan Beton Menggunakan Response Surface Methodology (Rsm). Masters thesis, Institut Teknologi Sepuluh Nopember.

Text 6005221006-Master_Thesis.pdf - Accepted Version Restricted to Repository staff only until 1 September 2025. Download (5MB) | Request a copy

Abstract

Urease merupakan enzim yang dapat menghidrolisis urea menjadi amonia dan kalsium karbonat. Keretakan pada struktur beton disebabkan oleh tegangan berlebih dan penyusutan pada beton. Grouting merupakan metode perbaikan dengan memasukan material konstruksi berupa semen dan air ke dalam rongga pada retakan beton. Kelemahan metode grouting yaitu viskositas tinggi dan dapat mencemari lingkungan. Sehingga, diperlukan solusi untuk memperbaiki keretakan beton yang efektif dan ramah lingkungan, yaitu menggunakan Enzyme Induce Carbonate Precipitation dengan memanfaatkan urease oleh bakteri ureolitik yang berperan sebagai katalisator pengendapan kalsium karbonat dengan mengisi celah keretakan beton. Injeksi pada retakan beton dilakukan menggunakan larutan EICP yang terdiri urease, urea dan CaCl2. Urease diperoleh dari bakteri ureolitik yang diisolasi dari dari Gunung Lumpur (Mud Volcano). Penelitian ini bertujuan untuk mengetahui kondisi optimum produksi urease menggunakan faktor suhu, pH, konsentrasi substrat dengan mengukur aktivitas urease tertinggi dan mengetahui kondisi optimum proses presipitas kalsium karbonat dengan larutan EICP yang diaplikasikan untuk perbaikan keretakan beton menggunakan faktor konsentrasi urea, dan konsentrasi CaCl2 dengan mengukur uji kuat tekan beton. Optimasi dilakukan menggunakan metode Response Surface Methdoology (RSM). Karakterisasi urease dilakukan menggunakan Nessler untuk uji aktivitas urease, crude urease dipurifikasi dengan amonium sulfat, dan analisis kadar protein menggunakan metode Bradford, serta dilakukan uji titik isoelektrik. Urease dengan nilai aktivitas spesifik tertinggi terbaik digunakan untuk aplikasi perbaikan keretakan pada beton dengan dilakukan uji kuat tekan beton (Concrete Compressive Strength Test) menggunakan UTM. Hasil dari penelitian ini yaitu didapatkan 10 isolat bakteri ureolitik dari Gunung Lumpur (Mud Volcano) dan didapatkan isolat bakteri BM8 dengan aktivitas tertinggi yang menunjukkan perubahan warna ungu pada media skrining Christesen’s Urea Agar, isolat bakteri BM8 berjenis gram positif dan berbentuk basil. Diperoleh aktivitas spesifik urease tertinggi yaitu sebesar 9773 U/mg dengan kondisi optimum produksi urease pada pH 7, suhu 35C, dan konsentrasi substrat 2%. Uji kuat tekan beton retak tertinggi yaitu 18,22 MPa dengan kondisi optimum larutan injeksi konsentrasi urea 500 mM dan konsentrasi CaCl2 500 mM.
====================================================================================================================================
Urease is an enzyme that can hydrolyze urea into ammonia and calcium carbonate. Cracks in concrete structures are caused by excess stress and shrinkage in concrete. Grouting is a repair method by inserting construction materials in the form of cement and water into the voids in the concrete cracks. The weakness of the grouting method is the high viscosity and can pollute the environment. Thus, a solution is needed to repair concrete cracks that are effective and environmentally friendly, namely using Enzyme Induced Carbonate Precipitation by utilizing urease by ureolytic bacteria which act as a catalyst for the deposition of calcium carbonate to fill the cracks in concrete. Injection into concrete cracks was carried out using an EICP solution consisting of urease, urea and CaCl2. Urease is obtained from ureolytic bacteria isolated from Gunung Lumpur. This study aims to determine the optimum conditions for urease production using temperature, pH, and substrate concentration factors by measuring the highest urease activity and to determine the optimum conditions for the calcium carbonate precipitation process with EICP solution which is applied to repair cracks in concrete using the urea concentration and CaCl2 concentration by measuring the Concrete Compressive Strength Test. Optimization was carried out using the Response Surface Methodology (RSM) method. Urease characterization was carried out using Nessler to test urease activity, crude urease was purified with ammonium sulfate, and protein content analysis was carried out using the Bradford method, as well as an isoelectric point test. Urease with the highest specific activity value is best used for crack repair applications in concrete by conducting a Concrete Compressive Strength Test using UTM. The results of this study were 10 isolates of ureolytic bacteria from Mud Volcano and BM8 isolates with the highest activity showing a purple discoloration on Christesen's Urea Agar screening medium, BM8 isolates were gram-positive and bacillus-shaped. The highest specific activity of urease was obtained, namely 9773 U/mg with optimum conditions for urease production at pH 7, temperature 35C, and substrate concentration of 2%. The highest compressive strength test for cracked concrete was 18.22 MPa with the optimum conditions for injection solution with 500 mM urea concentration and 500 mM CaCl2 concentration.

Item Type:	Thesis (Masters)
Uncontrolled Keywords:	Bakteri Ureolitik, Urea, Urease, Presipitasi Kalsium Karbonat, Response Surface Methodology; Ureolytic Bacteria, Grouting, Urea, Urease, Response Surface Methodology
Subjects:	Q Science > Q Science (General) Q Science > QH Biology Q Science > QH Biology > QH301 Biology Q Science > QR Microbiology Q Science > QR Microbiology > QR74.8 Bacteria
Divisions:	Faculty of Science and Data Analytics (SCIENTICS) > Biology > 46101-(S2) Master Thesis
Depositing User:	Fellycita Kartika Afriliona
Date Deposited:	24 Aug 2023 06:28
Last Modified:	24 Aug 2023 06:31
URI:	http://repository.its.ac.id/id/eprint/101800

Actions (login required)

View Item