Optimasi Medium dan Kondisi Fermentasi untuk Produksi Biomassa Lactiplantibacillus plantarum DLBSK207 dengan Response Surface Methodology

Abstract

Penelitian ini bertujuan untuk mengoptimalkan medium dan kondisi fermentasi untuk produksi biomassa Lactiplantibacillus plantarum DLBSK207 menggunakan metode Response Surface Methodology (RSM). Metode RSM dipilih karena kemampuannya dalam mengevaluasi interaksi antar variabel dengan efisien, serta mengurangi jumlah percobaan yang diperlukan untuk mencapai kondisi optimum. Penelitian ini dilakukan di laboratorium PT XYZ, yang memiliki fasilitas dan teknologi yang mendukung penelitian ini. Optimasi menggunakan kombinasi sumber karbon, sumber nitrogen, kondisi lingkungan seperti pH awal medium dan suhu inkubasi. Mikronutrien yang sama digunakan di semua formula seperti natrium asetat 5,0 g/L; MgSO4·7H2O 0,1 g/L; K2HPO4 2,0 g/L; MnSO4·H2O 0,05 g/L dan Tween 80 1,0 g/L. Metode One-Factor-At-a-Time (OFAT) digunakan sebagai tahap awal untuk mengidentifikasi pengaruh tiap variabel, kemudian dilanjutkan optimasi ke tahapan kedua menggunakan metode Plackett-Burman Design (PBD), untuk menyaring variabel-variabel yang memberikan pengaruh terbesar terhadap respon yang dihasilkan. Enam faktor pertumbuhan yang sangat berpengaruh dipilih dari hasil OFAT, dan enam variabel terpilih (glukosa, maltosa, ekstrak ragi, pepton, pH awal medium, dan suhu inkubasi) digunakan dalam optimasi PBD. Sebanyak 46 formula diuji menggunakan Box-Behnken Design (BBD) dengan parameter respon viabilitas sel, berat sel kering, dan pH akhir. Formula optimum terdiri dari glukosa 33,76 g/L, ekstrak ragi 32,59 g/L, dan pepton 23,38 g/L, pada pH awal 6,0 dan suhu 35°C. Validasi dilakukan lima kali, menunjukkan viabilitas sel 9,30 log CFU/mL, berat sel kering 4,319 g/L, dan pH akhir 4,82. Medium hasil optimasi menghasilkan berat sel kering 1,56 kali lebih tinggi dibandingkan MRS broth. Produksi 10 L pada pH 6,0 dengan NH4OH 25% meningkatkan biomassa 2,32 kali lebih tinggi dari MRS broth. Optimasi ini meningkatkan produksi biomassa Lactiplantibacillus plantarum DLBSK207, cocok untuk skala produksi besar.

Kata kunci: berat sel kering, Lactiplantibacillus plantarum DLBSK207, optimasi medium, Response Surface Methodology, viabilitas sel

This study focuses on optimizing the medium and fermentation conditions to produce Lactiplantibacillus plantarum DLBSK207 biomass using the Response Surface Methodology (RSM). The RSM method was chosen for its ability to efficiently evaluate the interactions between variables while minimizing the number of experiments needed to achieve optimum conditions. This research was conducted in the laboratories of PT XYZ, which are equipped with the necessary facilities and technology to support this testing. The optimization process involves a combination of carbon and nitrogen sources, specifically glucose, yeast extract, and peptone, as well as environmental conditions during fermentation, including the initial pH of the medium and incubation temperature. The same micronutrients are used across all formulations: 5.0 g/L sodium acetate; 0.1 g/L MgSO4·7H2O; 2.0 g/L K2HPO4; 0.05 g/L MnSO4·H2O and 1.0 g/L Tween 80. The One-Factor-At-a-Time (OFAT) method was initially employed to identify the impact of each variable. Following this, optimization proceeded to the second stage using the Plackett-Burman Design (PBD) to filter variables with the most significant influence on the response. Six critical components identified by OFAT (glucose, maltose, yeast extract, peptone, initial medium pH, and incubation temperature) were selected for PBD optimization. A total of 46 formulations were tested using Box-Behnken Design (BBD), with response parameters including cell viability, dry cell weight, and final pH. The optimum formula consisted of 33.76 g/L glucose, 32.59 g/L yeast extract, and 23.38 g/L peptone, at an initial pH of 6.0 and a temperature of 35°C. Validation was conducted five times, yielding cell viability of 9.30 log CFU/mL, dry cell weight of 4.319 g/L, and a final pH of 4.82. The optimized medium resulted in 1.56 times higher dry cell weight compared to MRS broth. Production in a 10 L volume at pH 6.0 using 25% NH4OH led to a 2.32-fold increase in biomass compared to MRS broth. This optimization significantly enhanced biomass production of Lactiplantibacillus plantarum DLBSK207, making it suitable for larger-scale production.

Keywords: dry cell weight, Lactiplantibacillus plantarum DLBSK207, optimized medium, Response Surface Methodology, viable cells