The Role of Dietary Phenolic Compounds in Protein Digestion and Processing Technologies to Improve Their Antinutritive Properties

Abstract

Digestion is the key step for delivering nutrients and bioactive substances to the body. The way different food components interact with each other and with digestive enzymes can modify the digestion process and affect human health. Understanding how food components interact during digestion is essential for the rational design of functional food products. Plant polyphenols have gained much attention for the bioactive roles they play in the human body. However, their strong beneficial effects on human health have also been associated with a negative impact on the digestion process. Due to the generally low absorption of phenolic compounds after food intake, most of the consumed polyphenols remain in the gastrointestinal tract, where they then can exert inhibitory effects on enzymes involved in the degradation of saccharides, lipids, and proteins. While the inhibitory effects of phenolics on the digestion of energy-rich food components (saccharides and lipids) may be regarded as beneficial, primarily in weight-control diets, their inhibitory effects on the digestion of proteins are not desirable for the reason of reduced utilization of amino acids. The effect of polyphenols on protein digestion is reviewed in this article, with an emphasis on food processing methods to improve the antinutritive properties of polyphenols.

Use of grape pomace in formulated feed for the rainbow trout fry, Oncorhynchus mykiss (Walbaum, 1792)

“…Under high polyphenolic intake, most polyphenols remain in the gastrointestinal tract because of the low absorption rate of phenolic compounds in the intestine. In this organ, these polyphenols produce inhibitory effects on enzymes involved in the degradation of nutrients, such as α-amylase, saccharides, lipases, and proteases (Cirkovic-Velickovic & Stanic-Vucinic, 2017;Marques et al, 2016), thus reducing nutrient digestibility (Adamidou et al, 2009). In this sense, a decrease in dry matter digestibility was recorded in the second experiment in treatments with higher phenolic content (D12 and D18).…”

“…Grape pomace (GP) is made from solid residues produced after the juice is extracted from grapes (around 20% of total), consisting of seeds, skin, and stems used in ethanol production by fermentation (Trošt et al, 2016). GP contains antinutritional factors (such as phenolic compounds) (Brenes, Viveros, Chamorro, & Arija, 2016), widely known as digestive enzyme inhibitors (Cirkovic-Velickovic & Stanic-Vucinic, 2017;Førde-Skjaervik, Refstie, Aslakse, & Skrede, 2006). In addition, it is of low nutritional value (protein ≤10%, lipids ≤12%, and carbohydrates 33-50% as fiber), which varies according to grape type and proportion of seeds, skin, and stems (Guerra-Rivas, Gallardo, Mantecón, del Alamo-Sanza, & Manso, 2016;Sousa et al, 2014).…”

Nutritional and Functional Properties of Extruded Cassava‐Soy Composite with Grape Pomace

“…The aromatic nuclei and hydroxyl group of the aromatic ring of the phenolic compounds provide the principal binding sites for protein‐phenolic complexation . It has been suggested that hydrogen bonding between the phenolic hydroxyl group and the NH‐ and CO‐groups of proteins are involved in protein–phenolics interaction . These interactions result in formation of insoluble complexes which ultimately reduces the digestibility of proteins.…”

Perspectives of lupine wholemeal protein and protein isolates biodegradation

“…Polyphenols decrease protein digestion in vitro due to their covalent, as well as noncovalent interactions with proteins. Regarding the influence of phenolic compounds on the digestibility of other nutrients, after food intake, most of the consumed polyphenols remain in the GIT, where they can then exert inhibitory effects on enzymes involved in the degradation of saccharides, lipids and proteins (Cirkovic Velickovic & Stanic‐Vucinic, ). Polyphenol compounds have been shown to inhibit crucial enzymes involved in the digestion of starch and lipid (Boath et al ., ; Sakulnarmrat et al ., ; Lochocka et al ., ), as well as protein (He et al ., ).…”

“…Polyphenol compounds have been shown to inhibit crucial enzymes involved in the digestion of starch and lipid (Boath et al ., ; Sakulnarmrat et al ., ; Lochocka et al ., ), as well as protein (He et al ., ). The effects of phenolic compounds on protein digestibility are consequences of their binding to endogenous proteins, mainly digestive proteases (inhibition, activation, none), as well as protein substrates, which further influences protease activity and protein substrate accessibility (Cirkovic Velickovic & Stanic‐Vucinic, ). Therefore, the reactions of enzymes and protein substrates with phenolic compounds can be influenced by their AA sequence/profile, molecular size and structure.…”