ANTIBACTERIAL ACTIVITY OF LACTOBACILLUS PLANTARUM SM 7-4 CELL-FREE SUPERNATANT AND ETHANOLIC EXTRACT OF TURMERIC (\TEXTIT{CURCUMA LONGA}) AS BIOPRESERVATIVE FOR TOFU

• Main Author: Adyasa Khadifa, Gelar
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/79010
• Institution: Institut Teknologi Bandung

In tofu production process, turmeric is often used as a dye and for inhibiting its bacterial growth. On the other hand, secondary metabolites from bacteria Lactobacillus plantarum such as plantarisin and some organic acids which have antimicrobial effects have the prospect to be developed as a natural preservative. This study aims to determine the ability in inhibiting bacteria of metabolite from Lactobacillus plantarum SM 7-4 and ethanolic extract of turmeric (Curcuma longa) in increasing storage time of tofu- Growth medium of Lactobacillus plantarum SM 7-4 containing its metabolites was separated from the bacteria. Bacterial growth inhibition activity of cell-free supernatant (CFS) was reduced when heated and when its pH was neutralized. CFS has MIC for Escherichia coli at 20.000 gg/mL. Ethanol extract of turmeric rhizome (density of extract 1 % w/v was 0.94 g/mL) showed MIC to Escherichia coli at 287 yg/mL- Bacterial growth time test in room temperature showed the bland tofi-l with initial bacteria of 5.5 - 106 CFU/g had 1,2 hours until it hit 107 CFU/g. Tofu soaked with turmeric extract 2% w/v for 30 minutes had reduced initial bacterial count to 9.8 105 CFU/g and had 8 hour to hit aforementioned limit. Tofu soaked with CFS 2% w/v for 30 minutes had reduced initial bacterial count to 2.635 - 106 and had more than 12 hours to reach the limit. The CFS of Lactobacillus plantarum SM 74 with concentration of 2% w/v was able to increase the storage time of tofu better than the ethanol extract of mrmeric with concentration.of 2% w/v.