Dietary Heme-Containing Proteins: Structures, Applications, and Challenges

Abstract

Heme-containing proteins, commonly abundant in red meat and blood, are considered promising dietary sources for iron supplementation and fortification with higher bioavailability and less side effects. As the precise structures and accurate bioactivity mechanism of various heme-containing proteins (hemoglobin, myoglobin, cytochrome, etc.) are determined, many methods have been explored for iron fortification. Based on their physicochemical and biological functions, heme-containing proteins and the hydrolyzed peptides have been also widely utilized as food ingredients and antibacterial agents in recent years. In this review, we summarized the structural characterization of hemoglobin, myoglobin, and other heme proteins in detail, and highlighted recent advances in applications of naturally occurring heme-containing proteins as dietary iron sources in the field of food science and nutrition. The regulation of absorption rate, auto-oxidation process, and dietary consumption of heme-containing proteins are then discussed. Future outlooks are also highlighted with the aim to suggest a research line to follow for further studies.

Electrochemical transformations catalyzed by cytochrome P450s and peroxidases

“…137,138 Iron heme is the prosthetic group in hemoproteins such as myoglobin, hemoglobin, peroxidase, cytochromes, catalase, albumin, prion protein, guanylate cyclase and nitric oxide synthase (Scheme 3). [139][140][141] The central iron atom binds the oxygen and transfers it in various forms to small reactant molecules. There are various unbound cofactors used for enzymatic synthesis such as NADH, adenosine triphosphate (ATP), flavin mononucleotide (FMN), and thiamine diphosphate (ThDP).…”

Characteristics and molecular properties of crude hemeproteins extracted from Asian seabass gills using an ultrasound‐assisted process

“…1 Anemia, a most serious condition of iron deficiency, causes short-/long-term effects on an individual, particularly infants and pregnant women. 2 Currently, the most common iron supplements are divalent non-heme iron, such as iron(II) gluconate, iron(II) sulfate, and so forth. Nevertheless, these supplements exhibit certain adverse effects.…”

“…2 Additionally, the iron in these supplements can be easily affected by chelators such as tannic acid and phytic acid in foods, thus reducing iron absorption efficiency and adversely impacting the supplement's effectiveness. 2 However, iron-containing proteins from natural sources are gaining popularity as dietary supplements due to their high bioavailability and low cytotoxicity. 3 Natural iron-containing proteins are the primary source of iron that is required by living cells for growth and building enzymes, proteins, and hormones.…”

“…3 Natural iron-containing proteins are the primary source of iron that is required by living cells for growth and building enzymes, proteins, and hormones. 2 In terms of nutrition, dietary iron is typically divided into two types: heme iron and non-heme iron. Heme contains porphyrin, to which one iron atom is bound.…”

“…In general, bovine and porcine hemeproteins have been widely applied and are readily available as supplements with higher iron content and fewer adverse effects. 2 However, the restrictions of some religions limit their use. Thus, alternative sources of iron, especially from the leftover of fish processing industries, have drawn the attention from both entrepreneurs and consumers.…”