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Opinion Article - Biology & Medicine Case Reports (2022) Volume 6, Issue 1

Acquiring nutrition through single cell protein.

Olivia T*

Department of Environmental Engineering, Technical University of Denmark, Denmark

*Corresponding Author:
Olivia T
Department of Environmental Engineering,
Technical University of Denmark,

Received: 29-Dec-2021, Manuscript No. AABMCR-22-101; Editor assigned: 30-Dec-2021, PreQC No. AABMCR-22-101(PQ); Reviewed: 16-Jan-2022, QC No AABMCR-22-101; Revised: 19-Jan-2022, Manuscript No. AABMCR-22-101(R); Published: 27-Jan-2022, DOI:10.35841/aabmcr-6.1.101

Citation: Olivia T. Acquiring nutrition through single cell protein. Biol Med Case Rep. 2022;6(1):101

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Single cell proteins (SCPs) are obtained as dried cells and/or purified proteins from the cells of microorganisms with high protein content. SCPs have a high protein content with a wide amino acid range, low fat content, and a greater protein: carbohydrate ratio than forages, making them an appealing nutrient supplement for humans. Vitamins such as thiamine, riboflavin, pyridoxine, nicotinic acid, pantothenic acid, folic acid, biotin, cyanocobalamin, ascorbic acid, -carotene, and tocopherol; important amino acids such as lysine and methionine; minerals; nucleic acids and lipids are all present in SCPs. SCPs have previously been utilised in a variety of applications, including food (aroma carriers, vitamin carriers, emulsifying acids, etc.) and feed (pigs, poultry, cattle, fish), as well as the paper and lead industries [1].

Bacterial Metabolism

Enzymatic assimilation (the intake and use of organic and inorganic substances essential for cellular growth and maintenance) and dissimilation reactions are common metabolic processes in bacteria (the oxidation and breakdown of substrate). Assimilation reactions are endergonic, meaning they consume energy, whereas dissimilation reactions are exergonic, meaning they produce it. These processes are important in the cell's fundamental functions and constitute the basis for bacterial cell self-replication.

B-complex vitamins are functional coenzymes that catalyse various oxidation–reduction reactions in bacterial enzymatic systems and are important in cell development and energy transformation processes. The biological oxidation of organic substances in SCP metabolism produces simple organic and/or inorganic chemicals, as well as ATP [2]. These chemicals are required by the bacterial cell's anabolic processes. Within heterotrophic metabolism, bacteria have two forms of energy production: anaerobic respiration or fermentation and aerobic respiration. Energy can be produced in both aerobic and anaerobic conditions.

The fermentation is anaerobic, which means that the terminal electron acceptor (e.g., SO42-, NO3–, or fumarate) is not O2. Glycolysis converts glucose to pyruvate, which produces ATP and NADH (by the conversion of NAD). In the presence of NADH, pyruvate produces fermentation end products. Glucose catabolism is a part of aerobic respiration. Through electron transport and chemiosmosis, the pyruvate produced by glucose breakdown produces acetic acid, carbon dioxide, and NADH. Acetic acid reacts with coenzyme A to form acetyl SCoA, which then detaches from CoA to join the reaction cycle (Krebs or Glyoxylate).

Algal Metabolism

The term "micro-algal metabolism" refers to a set of processes that includes both biochemical and nutrition transport pathways. Intake nutrients are transformed into nutritional principles needed for important functions like growth, reproduction, and defence systems via a metabolic pathway. The processes for acquiring carbon sources, light capture, food assimilation (nitrogen and sulphur), and production of distinct secondary metabolites distinguish microalgal metabolism from other organisms' metabolisms.

The micro-algae have oxygen-evolving photosynthesis, which is a distinguishing trait that sets them apart from other lower eukaryotes. At the thylakoid membrane level, this metabolic activity is defined by certain reactions that are commonly induced in the presence of light. The basic chemo-organotrophic metabolism of algae is similar to that of bacteria. Anabolic activities in algae can occur in the presence of light (photolithotrophic) or in the absence of light (cryptotrophic). Specialized enzymatic systems, such as ATP synthases, the cytochrome b6–f complex, or enzymes specific to the photosynthetic carbon-reduction cycle, catalyse the photorespiration process. Photosynthetic reactions in microalgae produce carbohydrates in the form of phosphates. The photolithotrophic metabolism of algae involves routes that are not possible to follow in the dark. Photons, nitrogen, ammonium nitrate, ammonium sulphate, ammonium di-hydrogen phosphate, and carbon dioxide are all used in the production of critical C skeletons in known linear processes. Only organic carbon is available to microalgae that grow in the dark [3,4,5].


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