Interactions between Salivary Proteins and Apple Polyphenols and the Fate of Complexes during Gastric Digestion.

Beneficial polyphenols in apples can reach the stomach as complexes formed with salivary proteins. The present study aimed at documenting the interactions between salivary proteins and cider apple polyphenols and the fate of complexes during gastric digestion. A polyphenolic extract was mixed with human saliva, and interactions were characterized by analyzing proteins and polyphenols in the insoluble and soluble fractions of the mixtures, before and after in vitro gastric digestion.

Effect of some local plant extracts on fatty acid composition of fish () during smoking and sun drying in the Far-North region of Cameroon.

The objective of this study was to assess the antioxidant activities of three plant extracts ( leaves, fruits, and leaves) and to evaluate their effects on the preservation of fish polyunsaturated fatty acids (PUFAs) during smoking and sun-drying processes. PUFAs are highly prone to oxidation during fish processing. The plant extracts were analyzed for their polyphenol contents and were evaluated for their total antiradical capacity.

Physical and Oxidative Stabilization of Oil-In-Water Emulsions by Roasted Coffee Fractions: Interface- and Continuous Phase-Related Effects.

Emulsions fortified with polyunsaturated fatty acids are highly relevant from a nutritional perspective; however, such products are prone to lipid oxidation. In the current work, this is mitigated by the use of natural antioxidants occurring in coffee. Coffee fractions with different molecular weights were extracted from roasted coffee beans.

Oil Bodies from Chia ( L.) and Camelina ( L.) Seeds for Innovative Food Applications: Microstructure, Composition and Physical Stability.

Exploring and deciphering the biodiversity of oil bodies (OBs) recovered from oilseeds are of growing interest in the preparation of sustainable, natural and healthy plant-based food products. This study focused on chia ( L.) and camelina ( L.

Interactions between Salivary Proteins and Dietary Polyphenols: Potential Consequences on Gastrointestinal Digestive Events.

The present review documents the current knowledge and hypotheses on how polyphenols-saliva interactions may modulate the bioaccessibility or bioavailability of nutrients and highlights research prospects in the field. After an updated description of the different classes of dietary polyphenols and their modifications by food processing or digestion, an overview of interactions between salivary proteins and polyphenols (with an emphasis on tannins) is provided. studies show that the solubility of salivary protein-tannin complexes in gastric conditions depends on the degree of tannin polymerization, while complexes are partly solubilized by bile salts.

Biochemical and physical-chemical characterisation of leaf proteins extracted from Cichorium endivia leaves.

This study provides a detailed characterisation of a leaf protein concentrate (LPC) extracted from Cichorium endivia leaves using a pilot scale process. This concentrate contains 74.1% protein and is mainly composed of Ribulose-1,5-BISphosphate Carboxylase/Oxygenase (RuBisCO).

NMR structural elucidation of dehydrodimers resulting from oxidation of 5-O-caffeoylquinic acid in an apple juice model solution.

During apple juice and cider-making processes, phenolic compounds undergo enzymatic oxidation. 5-O-caffeoylquinic acid (CQA) is one of the major hydroxycinnamic acid derivatives and it is the preferential substrate for polyphenol oxidase (PPO) in apple juices. Consequently, CQA dehydrodimers (MW 706 Da) are among the main products resulting from CQA oxidation.

Preparative isolation of apple flavan-3-ols monomers and oligomers using pH-zone-refining centrifugal partition chromatography combined with reversed-phase liquid chromatography.

Flavan-3-ols (catechin monomers and procyanidins) are the main class of polyphenols in apples and are found in high concentrations in cider apple varieties. They are known to be involved in bitterness and astringency in apple-based beverages, and also contribute to polyphenol nutritional intake.Therefore, highly purified flavan-3-ol fractions isolated from raw materials are needed to study their various properties.

Reactivity of flavanols: Their fate in physical food processing and recent advances in their analysis by depolymerization.

Flavanols, a subgroup of polyphenols, are secondary metabolites with antioxidant properties naturally produced in various plants (e.g., green tea, cocoa, grapes, and apples); they are a major polyphenol class in human foods and beverages, and have recognized effect on maintaining human health.

Interactions between polyphenol oxidation products and salivary proteins: Specific affinity of CQA dehydrodimers with cystatins and P-B peptide.

Throughout the apple juice and cider making process, polyphenols undergo enzymatic oxidation which generates a great variety of polyphenol oxidation products. Since 5'-O-Caffeoylquinic acid (CQA) is one of the major phenolic compounds and the preferential substrate for polyphenoloxidase in apple juice, its oxidation leads to the formation of newly formed molecules by which dehydrodimers (MW 706 Da) are included. Interactions of salivary proteins (SP) with native polyphenols is a well-known phenomenon, but their interactions with polyphenol oxidation products has not been studied yet.

Structural characterization of native and oxidized procyanidins (condensed tannins) from coffee pulp (Coffea arabica) using phloroglucinolysis and thioglycolysis-HPLC-ESI-MS.

Procyanidins from coffee pulp are responsible from the limited valorization of this by-product. Information about procyanidin structure is still scarce and imprecise. The aim of this work was to study the native and oxidized procyanidins from coffee pulp with respect to composition and structure.

Tannin-controlled micelles and fibrils of κ-casein.

Effects of green tea tannin epigallocatechin-gallate (EGCG) on thermal-stress-induced amyloid fibril formation of reduced carboxymethylated bovine milk protein κ-casein were studied by dynamical light scattering and small angle X-ray scattering (SAXS). Two populations of aggregates, micelles, and fibrils dominated the time evolution of light scattering intensity and of effective hydrodynamic diameter. SAXS experiments allowed us to resolve micelles and fibrils so that the time dependence of the scattering profile revealed the structural evolution of the two populations.

Data set on hydroxycinnamic acid ester analysis from the cell walls of apples and grapes.

Data on the esters of hydroxycinnamic acids (HCAs) from the cell walls of wine grapes (Cabernet franc) and cider apples (Douce Moen and Guillevic) were acquired. Caffeic acid, -coumaric acid (CA) and ferulic acid (FA) monomers were identified by HPLC-UV/MS. Means to limit the oxidative degradation during cell wall preparation were assessed by the yield of HCA recovered after alkaline extraction.

Heat-unstable apple pathogenesis-related proteins alone or interacting with polyphenols contribute to haze formation in clear apple juice.

Physico-chemical instability is a damaging defect that can occur in clear bottled beverages leading to the formation of haze. In a previous study, we showed the presence of proteins in haze gathered from apple juices. For the first time, proteomics was used to sequence and identify four pathogenesis-related proteins (PRPs) from the haze of a commercial apple juice.

Phenolic distribution in apple epidermal and outer cortex tissue by multispectral deep-UV autofluorescence cryo-imaging.

Phenolic compounds in fruit are involved in responses to biotic and abiotic stresses and are responsible for organoleptic properties. To establish the distribution of these secondary metabolites at the tissue and sub-cellular scales, mapping of fluorescence in apple epidermis and outer cortex tissue in cryogenic condition was performed after deep-UV excitation at 275 nm. Douce Moën and Guillevic cider apple varieties were sampled and frozen after harvest, after 30 days at 4 °C and after 20 days at room temperature.

Preparative fractionation of 5'-O-caffeoylquinic acid oxidation products using centrifugal partition chromatography and their investigation by mass spectrometry.

When apples are processed into juices or ciders, a great variety of neoformed molecules are generated by enzymatic oxidation of polyphenols. These phenolic oxidation products could be responsible of specific organoleptic properties in apple juices and ciders. 5'-O-Caffeoylquinic acid (CQA) is the major hydroxycinnamic acid in apple and the preferential substrate of apple polyphenoloxidase (PPO).

Self-aggregation of oxidized procyanidins contributes to the formation of heat-reversible haze in apple-based liqueur wine.

The ability of tannins to self-associate or form complexes with other macromolecules has important nutritional implications but can also result in defects in beverages. In addition, oxidation may be involved in the aggregation properties of tannins. In order to assess the impact of tannin oxidation on their self-association, oligomeric procyanidins were oxidized in a model solution and their aggregation kinetics were studied using light scattering.

Screening of ordinary commercial varieties of apple fruits under different storage conditions for their potential vascular and metabolic protective properties.

Epidemiological studies reported that apple consumption is associated with a decrease of cardiovascular and metabolic dysfunction, probably due to the polyphenols and fibers present in this fruit. The storage conditions and genetic origin of apples have been reported to influence their content and, as a consequence, their pharmacological properties. The present study evaluated the influence of varieties and storage conditions of traditional and highly appreciated apples including Gala, Golden Delicious, Granny Smith and Pink Lady varieties after harvest and storage under classic cold conditions, under a controlled atmosphere, or under extreme ultra-low oxygen conditions.

Exploring the Degradation of Gallotannins Catalyzed by Tannase Produced by Aspergillus niger GH1 for Ellagic Acid Production in Submerged and Solid-State Fermentation.

Due to great interest on producing bioactive compounds for functional foods and biopharmaceuticals, it is important to explore the microbial degradation of potential sources of target biomolecules. Gallotannins are polyphenols present in nature, an example of them is tannic acid which is susceptible to enzymatic hydrolysis. This hydrolysis is performed by tannase or tannin acyl hydrolase, releasing in this way, biomolecules with high-added value.

Haze in Apple-Based Beverages: Detailed Polyphenol, Polysaccharide, Protein, and Mineral Compositions.

Producers of apple-based beverages are confronted with colloidal instability. Haze is caused by interactions between molecules that lead to the formation of aggregates. Haze composition in three apple-based beverages, namely, French sparkling cider, apple juice, and pommeau, was studied.

Polyphenol Interactions Mitigate the Immunogenicity and Allergenicity of Gliadins.

Wheat allergy is an IgE-mediated disorder. Polyphenols, which are known to interact with certain proteins, could be used to reduce allergic reactions. This study screened several polyphenol sources for their ability to interact with gliadins, mask epitopes, and affect basophil degranulation.

Historical biogeography of Reticulitermes termites (Isoptera: Rhinotermitidae) inferred from analyses of mitochondrial and nuclear loci.

Termites of the genus Reticulitermes are ecologically and economically important wood-feeding social insects that are widespread in the Holarctic region. Despite their importance, no study has yet attempted to reconstruct a global time-scaled phylogeny of Reticulitermes termites. In this study, we sequenced mitochondrial (2096bp) and nuclear (829bp) loci from 61 Reticulitermes specimens, collected across the genus' entire range, and one specimen of Coptotermes formosanus, which served as an outgroup.

HPLC-DAD-MS Profiling of Polyphenols Responsible for the Yellow-Orange Color in Apple Juices of Different French Cider Apple Varieties.

The pigments responsible for the yellow-orange coloration of apple juices have remained largely unknown up to now. Four French cider apple juices were produced in conditions similar to those used in the cider-making industry. The oxidized juices, characterized using the CIE L a b parameters, displayed various colors depending on the apple variety and native phenolic composition.

QTL analysis and candidate gene mapping for the polyphenol content in cider apple.

Polyphenols have favorable antioxidant potential on human health suggesting that their high content is responsible for the beneficial effects of apple consumption. They control the quality of ciders as they predominantly account for astringency, bitterness, color and aroma. In this study, we identified QTLs controlling phenolic compound concentrations and the average polymerization degree of flavanols in a cider apple progeny.

Tissue and cellular localization of tannins in Tunisian dates (Phoenix dactylifera L.) by light and transmission electron microscopy.

A histological approach including light microscopy and transmission electron microscopy (TEM) was used to provide accurate information on the localization of condensed tannins in the edible tissues and in the stone of date fruits (Phoenix dactylifera L.). Light microscopy was carried out on fresh tissues after staining by 4-dimethylaminocinnamaldehyde (DMACA) for a specific detection of condensed tannins.