Flavin mononucleotide (FMN) is a vital coenzyme derived from riboflavin (vitamin B2). It plays a crucial role in various biological processes, particularly in the electron transport chain, where it assists in cellular respiration by facilitating the transfer of electrons. FMN is essential for the function of several enzymes, known as flavoproteins, which are involved in metabolic reactions. In addition to its role in energy production, FMN is important for the metabolism of fats, carbohydrates, and proteins. It also contributes to the synthesis of flavin adenine dinucleotide (FAD), another important coenzyme. Deficiencies in FMN can lead to various health issues, highlighting its significance in maintaining overall metabolic health.