Isolation of Bacteria from Kombucha to Evaluate Their Ability in Production of Bacterial Cellulose

Yeoh, Wei Jet (2024) Isolation of Bacteria from Kombucha to Evaluate Their Ability in Production of Bacterial Cellulose. Final Year Project (Bachelor), Tunku Abdul Rahman University of Management and Technology.

Text Yeoh Wei Jet_Full Text.pdf Restricted to Registered users only Download (8MB)

Abstract

Bacterial cellulose (BC) is an extremely sustainable and multipurpose biomaterial that can be utilized in various industrial applications, particularly in the pharmaceutical industry. Unlike plant cellulose, BC would not result in negative environmental impacts that cause global warming. It was found that different bacterial species produce cellulose with varying properties. Therefore, the discovery of superior cellulose-producing bacteria is highly desired. This study aimed to isolate bacteria from kombucha cultures for the production of BC. Glucose yeast mannitol and peptone (GYMP) agar supplemented with cycloheximide was used to isolate bacteria from two kombucha cultures. Screening for potential BC bacteria was performed by selecting the bacteria that grew and formed a chemotactic ring on Hestrin Scharmn (HS) soft agar through the soft-agar swim plate method. Bacteria isolates (A1 & A2) from one kombucha source were found to be gram-positive cocci, whereas bacteria isolates (B1 & B2) from another kombucha B were gram-negative bacilli. The water contents in A1, A2, B1, and B2 were 98.5%, 98.6%, 96.5%, and 96.9% respectively. The FTIR spectra of all BCs showed peaks at 3300-3350 cm-1 (–O–H stretching), 2850-2950 cm-1 (C–H stretching), 1600-1700 cm-1 (C-H deformation vibrations), 1300-1400 cm-1 (OH in-plane bonding), and 1000-1100 cm-1 (C-O stretching), all of which are similar to the peaks found in the spectrum of plant cellulose. The tensile strengths of A1 and A2 were 107.42 Nmm-2 and 133.07 Nmm-2, respectively, which were higher than 2.27 Nmm-2 and 7.94 Nmm-2 for B1 and B2. In short, BCs obtained from bacteria A1 and A2 are better than BCs from B1 and B2.