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Evaluation of the production of bio-products by the thermophilic bacterium Rhodothermus marinus

Mohammadi, Milad LU (2024) KBTM01 20241
Biotechnology (MSc)
Biotechnology (M.Sc.Eng.)
Abstract
In this study the thermophilic marine bacterium Rhodothermus marinus DSM 16675 was exploited for the production of biosurfactants. Different strategies employing batch, or a combination of batch and fed-batch cultivations were investigated. These cultivations were performed both on complex and defined media. The extracted crude biosurfactants were then analyzed with different methods such as FTIR, HPLC and mass spectrometry. The identified biosurfactants were saturated and unsaturated fatty acids with lengths ranging from C16:0 to C18:0. The LC-MS analysis on these samples revealed peaks at different retention times consisting of the same fatty acid precursor ion which is suggested to be due to different branching on the carbon chain.... (More)
In this study the thermophilic marine bacterium Rhodothermus marinus DSM 16675 was exploited for the production of biosurfactants. Different strategies employing batch, or a combination of batch and fed-batch cultivations were investigated. These cultivations were performed both on complex and defined media. The extracted crude biosurfactants were then analyzed with different methods such as FTIR, HPLC and mass spectrometry. The identified biosurfactants were saturated and unsaturated fatty acids with lengths ranging from C16:0 to C18:0. The LC-MS analysis on these samples revealed peaks at different retention times consisting of the same fatty acid precursor ion which is suggested to be due to different branching on the carbon chain. Furthermore, it was found that the exopolysaccharide (EPS) produced by this microorganism has emulsifying properties. The critical micelle concentration (CMC) of the crude EPS was calculated at 0.75 ± 0.01 g/L using advanced fluorometric method and curcumin as fluorescent probe. Moreover, the produced EPS was able to stabilize the water-in-oil emulsion at a concentration of 10 g/L with an emulsification index (% E24) of 59.3 ± 2.5 %. The reported EPS has the potential application in oil industry, but further experiments are required to fully utilize the properties of this emulsifier. (Less)
Popular Abstract
Nowadays we can find surfactants in many products that we daily use. Surfactants are compounds that can react both with water and fatty compounds such as vegetable oils and mix them together. This property gives rise to many potential applications from detergents to oil industry. Currently, most of the surfactants that are in use are derived from fossil fuel and consequently extensive research has been conducted to find more sustainable sources to produce these compounds. One such source are microorganisms such as bacteria. It has been suggested that bacteria produce surfactants during their growth to be able to utilize a variety of food sources as well as to increase their mobility. These surfactants that are produced by bacteria are... (More)
Nowadays we can find surfactants in many products that we daily use. Surfactants are compounds that can react both with water and fatty compounds such as vegetable oils and mix them together. This property gives rise to many potential applications from detergents to oil industry. Currently, most of the surfactants that are in use are derived from fossil fuel and consequently extensive research has been conducted to find more sustainable sources to produce these compounds. One such source are microorganisms such as bacteria. It has been suggested that bacteria produce surfactants during their growth to be able to utilize a variety of food sources as well as to increase their mobility. These surfactants that are produced by bacteria are called biosurfactants.
This research was focused on producing biosurfactants from a bacteria that was isolated from a hot spring where it thrived at high temperatures. More specifically, different parameters such as the concentration of nutrients were changed to see their effect on the production of biosurfactants. Different tests were done to see the composition of the biosurfactants as their structure influence their potential application. Consequently, two different types of biosurfactants were identified in this study but further analysis is required to unlock their full potential for industrial applications. (Less)
Please use this url to cite or link to this publication:
author
Mohammadi, Milad LU
supervisor
organization
course
KBTM01 20241
year
type
H2 - Master's Degree (Two Years)
subject
keywords
Rhodothermus marinus, biosurfactant, exopolysaccharide, fermentation, fatty acids, HPAEC-PAD, HPLC, MS, biotechnology
language
English
id
9161395
date added to LUP
2024-06-12 09:37:38
date last changed
2024-06-12 09:37:38
@misc{9161395,
  abstract     = {{In this study the thermophilic marine bacterium Rhodothermus marinus DSM 16675 was exploited for the production of biosurfactants. Different strategies employing batch, or a combination of batch and fed-batch cultivations were investigated. These cultivations were performed both on complex and defined media. The extracted crude biosurfactants were then analyzed with different methods such as FTIR, HPLC and mass spectrometry. The identified biosurfactants were saturated and unsaturated fatty acids with lengths ranging from C16:0 to C18:0. The LC-MS analysis on these samples revealed peaks at different retention times consisting of the same fatty acid precursor ion which is suggested to be due to different branching on the carbon chain. Furthermore, it was found that the exopolysaccharide (EPS) produced by this microorganism has emulsifying properties. The critical micelle concentration (CMC) of the crude EPS was calculated at 0.75 ± 0.01 g/L using advanced fluorometric method and curcumin as fluorescent probe. Moreover, the produced EPS was able to stabilize the water-in-oil emulsion at a concentration of 10 g/L with an emulsification index (% E24) of 59.3 ± 2.5 %. The reported EPS has the potential application in oil industry, but further experiments are required to fully utilize the properties of this emulsifier.}},
  author       = {{Mohammadi, Milad}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Evaluation of the production of bio-products by the thermophilic bacterium Rhodothermus marinus}},
  year         = {{2024}},
}