The results of experiments with rubber seed proteins and wheat gluten suggest that this process can be applied to agro-industrial residues.Īs the building blocks of proteins, amino acids are important components in food and feed. Hydrophobic selectivity of 0.6 mol-hydrophobic/mol-total free amino acids was observed after 6 h hydrolysis of wheat gluten and 24 h hydrolysis of rubber seed proteins and BSA. Combination of Pronase and Peptidase R showed the highest selectivity towards hydrophobic amino acids, roughly doubling the content of hydrophobic amino acids in the products compared to the original substrates. Hydrophobic selectivity was influenced by the combination of proteases and by the extent of hydrolysis. High degree of hydrolysis (>50 %) could be achieved. Several protease combinations were applied for hydrolysis of rubber seed protein concentrate, wheat gluten, and bovine serum albumin (BSA). Selectivity can be achieved by selection of starting material, selection of hydrolysis conditions, and separation of achieved hydrolysate. Here, we present methods for selective production of hydrophobic amino acids from proteins. Several essential amino acids for food and feed have hydrophobic side chains this property may also be exploited for subsequent separation. For clarity, the preceding region is not shown but its continuation indicated by an arrow head.Protein hydrolysis enables production of peptides and free amino acids that are suitable for usage in food and feed or can be used as precursors for bulk chemicals. The wiggly line is a cartoon representation of the polypeptide chain of the α-subunit of haemoglobin between His-F8 and the C-terminal Arg residue. 3 of the original, produced many years ago for teaching purposes. This movement is associated with breaking of ionic bonds between the subunits in the overall change in quaternary structure: The classic illustration of the importance of these dual properties of tyrosine is in Perutz’s description of the differences between the oxy- and deoxy- structures of haemoglobin, where oxygenation of the haem cause the movement of tyrosine from the hydrophobic interior of the protein to the hydrophilic surface. Indeed, one should ask how useful a particular classification is in any circumstance, and be aware of its limitations. It is important not to try to fit things into rigid classifications that may not be appropriate for them. The ring is aromatic and hydrophobic, but the hydroxyl substituent is hydrophilic. It has both hydrophobic and hydrophilic features and can exhibit bothīehaviours depending on the circumstances.

The answer to this question emerges from an examination of the structure of tyrosine - or, more strictly, the tyrosyl residue, which is how it exists in proteins, the concern of the question:

Hydrophobic amino acids function