Supervisors info:
Βασίλης Βαλδραμίδης, Αναπληρωτής Καθηγητής, Τμήμα Χημείας, ΕΚΠΑ (Επιβλέπων),
Γεώργιος Μάρκου Ανώτερος Ερευνητής ΙΤΑΠ, ΕΛΓΟ-ΔΗΜΗΤΡΑ,
Χαράλαμπος Προεστός Καθηγητής, Τμήμα Χημείας, ΕΚΠΑ
Summary:
In this postgraduate thesis, we examine the production and characterization of microbial biomass from methane-oxidizing bacteria, as an alternative protein source, which could be utilized in the future either in animal feed or even as an additive in human food. Specifically, all stages for the conventional production of biomass in the laboratory are outlined, including the factors that may affect the multiplication of methane-oxidizing bacteria, as well as the optimal conditions for the growth of liquid cultivations aimed at maximizing the production of microbial biomass rich in proteins. Furthermore, the analytical techniques for the characterization of the produced biomass are described, while at the same time, the detailed results of these analyses, the percentage concentration of the identified components, and their biological value are provided. Specifically, the produced biomass consists of 30% proteins, 15% carbohydrates, and 2% lipids. Additionally, the amino acid profile and lipid profile were determined using the analytical techniques HPLC-FLR and GC-BID, respectively. These results demonstrate the ability of methanotrophic bacteria to synthesize all essential amino acids for the formation of diverse proteins, while the synthesized lipids contribute to the general survival, growth, and adaptation of the bacteria in the cultures. Finally, using Nuclear Magnetic Resonance (NMR), a qualitative determination of the components of the liquid nutrient medium of the cultures was carried out, where several useful by-products of the metabolic pathway of methanotrophic bacteria were detected, such as ectoine, formaldehyde, methanol, PHA & PHB, ethanol, and squalene, which can be utilized by the food, pharmaceutical, and cosmetic industries.
Keywords:
Single cell protein production, Biomass characterization, Methane-Oxidizing bacteria, Method development and validation, Analytical techniques
