Methods of Protein Digestive Stability Assay - State of the Art

Protein identification and in vitro digestion of fractions from Tenebrio molitor

“…The different protein band pattern could be explained by different positions at which amino acids are cleaved in vitro by trypsin and chymotrypsin. It is known that pepsin splits proteins to smaller parts which increases its accessibility, but does not digest proteins to amino acids [5]; trypsin cleaves peptide bonds on the carboxyl side of arginine or lysine, and chymotrypsin usually cleaves peptide bonds on the carboxyl side of aromatic amino acids (phenylalanine, tryptophan and tyrosine) or leucine [37,38].…”

“…However, the nutritional value of a food protein is evaluated not only by its amino acid composition, but also by protein digestibility. Protein digestion in humans generally starts with pepsin cleavage in the stomach, subsequently trypsin and chymotrypsin digestion in the intestinal lumen, and the last step includes cleavage by proteases present on the intestinal surface [5]. In vitro digestion is often used as an approximation for in vivo processes [6].…”

“…During protein digestion and absorption in the human body, protein is broken down to amino acids and peptides by digestive enzymes [5]. Afterward, free amino acids and small peptides are absorbed through the gastrointestinal wall.…”

Proteomics in Forensic Sciences: Identification of the Nature of the Last Meal at Autopsy

“…The assessment of other kinds of protein foodstuff should be evaluated case-by-case. Indeed, the pepsin stability/susceptibility of most food proteins, which has been already established in vitro, should be confirmed in vivo, eventually in processed foodstuff and in the presence of other components constituting a real meal . To this purpose, milk contains a multitude of minor proteins, whose individual behavior in the stomach is only partly known .…”

“…Indeed, the pepsin stability/susceptibility of most food proteins, which has been already established in vitro, should be confirmed in vivo, eventually in processed foodstuff and in the presence of other components constituting a real meal. 30 To this purpose, milk contains a multitude of minor proteins, whose individual behavior in the stomach is only partly known. 31 Therefore, it could be evaluated in order to individuate novel milk-specific protein probes.…”