Health-Promoting Properties of Pectin-Polyphenol Complex Extracted from Olive Oil By-Product Alperujo: Antioxidant, Antiproliferative, and Anti-Inflammatory Activities.

This research explores the health-promoting properties of the pectin-polyphenol complex extracted from alperujo, a by-product of olive oil production. This study investigates the chemical composition and antioxidant activity of the extracts, revealing their high antioxidant activity in vitro. Cell viability assays conducted on colon carcinoma cells (Caco-2) demonstrate the inhibitory effect of the extracts on cell proliferation.

Antioxidant activity and inhibitory effects on angiotensin I-converting enzyme and α-glucosidase of trans-p-coumaroyl-secologanoside (comselogoside) and its inclusion complex with β-cyclodextrin. Bioaccessibility during simulated in vitro gastrointestinal digestion.

This study explored the impact of complexing comselogoside (COM) with β-cyclodextrin (β-CD) on antioxidant capacity and investigated its in vitro inhibitory effects against α-glucosidase and angiotensin I-converting enzyme (ACE). The COM: β-CD complex in three molar ratios (1:2, 1:1, and 2:1) showed significantly higher antioxidant activity compared to free COM, assessed by DPPH and ferric reducing power assays. COM exhibited weak to moderate α-glucosidase inhibition (IC 1221 μM) and notable ACE inhibition (IC 119.

Application of Thermo-Malaxation Followed by Three-Phase Centrifugation to Enable the Biorefinery of Alperujo, the Main By-Product of Olive Oil.

The pomace olive oil sector needs to improve its use of the main olive oil by-product, called alperujo, which is currently used mainly for combustion after extraction of pomace oil, with all the problems this process entails due to the high degree of humidity, organic load and phytotoxic substances. In this work, a solution at an industrial level that uses thermo-malaxation at a temperature close to 65 °C for one or two hours followed by centrifugation in three phases is proposed. In this way, over 40% of the pomace oil that is rich in minor compounds, a solid with a lower degree of humidity (55%), and a liquid aqueous fraction that is rich in bioactive compounds such as phenolics and sugars are obtained.

Isolation and structural determination of cis- and trans-p-coumaroyl-secologanoside (comselogoside) from olive oil waste (alperujo). Photoisomerization with ultraviolet irradiation and antioxidant activities.

p-Coumaroyl-6́-secologanoside (comselogoside) is a secoiridoid identified in large amounts in olive fruits, although no studies in vitro or in vivo of comselogoside have been reported. This work focuses on the recovery and purification of this compound from olive mill waste (alperujo). The successive isolation on Amberlite XAD-16 and Sephadex LH-20 resins, allowed a comselogoside extract with 80-85% of purity.

Inhibitory Effect of Olive Phenolic Compounds Isolated from Olive Oil By-Product on Melanosis of Shrimps.

Melanosis is an unsolved problem of the crustacean industry and the cause of great loss of value. This study investigates the effect of two potent, natural antioxidants isolated from olive waste (hydroxytyrosol, HT and 3,4-dihydroxyphenylglycol, DHPG) and three novel HT-derivatives containing selenium and sulfur (dihydroxytyrosyl diselenide, -hydroxytyrosyl selenourea, and -hydroxytyrosyl thiourea) on the prevention of melanosis in Atlantic ditch shrimp () during refrigerated storage. These results clearly demonstrate the positive inhibitory effect of DHPG and dihydroxytyrosyl diselenide on delaying melanosis in vivo, although this effect was not dose dependent.

Antiproliferative Activity of Olive Extract Rich in Polyphenols and Modified Pectin on Bladder Cancer Cells.

Bladder cancer (BC) is one of the most common human cancers. There is an interest in controlling and treating BC and other types of cancer via the use of natural substances and/or combination chemotherapy. Modified forms of pectin have been reported to possess anticancer bioactivity related to the interaction of galactosyl, a main component of pectin, with galectin-3, a carbohydrate-binding protein that is overexpressed on many types of cancer cells.

Effect of edible pectin-fish gelatin films containing the olive antioxidants hydroxytyrosol and 3,4-dihydroxyphenylglycol on beef meat during refrigerated storage.

The objective of this research was to evaluate the effect of the addition of two antioxidants naturally present in olives, hydroxytyrosol (HT) and 3,4-dihydroxyphenylglycol (DHPG), to a pectin-fish gelatin edible film on the preservation of raw beef meat during refrigerated storage. A new composite film that included beeswax was also prepared, resulting in a reduction in the film's oxygen permeability. Results showed that the meat samples wrapped with film containing antioxidants reduced the formation of oxidation products in the form of thiobarbituric acid reaction substances (TBARS) compared with control film without antioxidants.

Selenium and sulphur derivatives of hydroxytyrosol: inhibition of lipid peroxidation in liver microsomes of vitamin E-deficient rats.

Purpose: The objective of this study was to evaluate the capacity of modified phenols synthesized from hydroxytyrosol, a natural olive oil phenol, specifically those containing a selenium or sulphur group, to inhibit lipid peroxidation.

Methods: The compounds' abilities to inhibit lipid peroxidation in liver microsomes obtained from vitamin E-deficient rats were compared to hydroxytyrosol.

Results: All synthetic compounds had a significant higher ability to inhibit lipid peroxidation than hydroxytyrosol.

Physical and functional properties of pectin-fish gelatin films containing the olive phenols hydroxytyrosol and 3,4-dihydroxyphenylglycol.

This study describes the development of a composite edible film based on pectin and fish skin protein capable of protecting food from microbial attack and oxidative degradation. The film was prepared with glycerol as plasticizer and the antioxidant and antimicrobial phenolic compounds hydroxytyrosol (HT) and 3,4-dihydroxyphenylglycol (DHPG), extracted from olive fruit, as active agents. The influence of the concentration of plasticizer and active HT/DHPG on the mechanical and functional properties of the films was investigated, with values of water vapor permeability (WVP) between 0.

Complexation of hydroxytyrosol and 3,4-dihydroxyphenylglycol with pectin and their potential use for colon targeting.

Hydroxytyrosol (HT) and 3,4-dihydroxyphenylglycol (DHPG) are two phenolic antioxidants naturally found in olive fruit with anti-inflammatory properties. This study explored the interaction of pectin with HT and DHPG via their encapsulation into pectinate beads. Purification by size exclusion chromatography, changes in the fluorescence spectrum of the HT and pectin, and MALDI TOF-TOF analysis suggested the existence of the phenol-pectin complexes.

Influence of pH on the antioxidant phenols solubilised from hydrothermally treated olive oil by-product (alperujo).

The application of a novel industrial process based on the hydrothermal treatment of olive oil waste (alperujo) led to a final liquid phase that contained a high concentration of simple phenolic compounds. In this study the effect of pH on phenol extraction with ethyl acetate from the aqueous phase of hydrothermally treated alperujo at 160°C/60min (without modification, pH 4.5, and adjusted to pH 2.

Antioxidant phenolic extracts obtained from secondary Tunisian date varieties (Phoenix dactylifera L.) by hydrothermal treatments.

Three common non-commercial Tunisian date varieties were treated by two thermal systems, obtaining a liquid fraction which was characterized and its antioxidant capacity determined. The concentration of total phenols in the three varieties (Smeti, Garen Gazel, and Eguwa) was increased by steam explosion treatment up to 5311, 4680, and 3832 mg/kg of fresh dates, and their antioxidant activity up to 62.5, 46.

Isolation and identification of minor secoiridoids and phenolic components from thermally treated olive oil by-products.

The application of an industrial process based on the hydrothermal treatment of 160 °C/60 min of alperujo, a by-product of olive oil extraction, allows the formation of a liquid phase containing a high concentration of phenolic and secoiridoid compounds. Ethyl acetate was used to extract these phenolic compounds from the aqueous matrix. In this study, the isolation with polyamide and XAD resin allowed detection of the presence of phenolic compounds in minor concentrations.

Isolation and Characterization of a Secoiridoid Derivative from Two-Phase Olive Waste (Alperujo).

A secoiridoid derivative was isolated from the ethyl acetate extract of two-phase olive waste (alperujo). The structure of this compound was fully characterized as s-trans-(E)-3-(1-oxobut-2-en-2-yl)glutaric acid. The spectroscopic data, including one- and two-dimensional nuclear magnetic resonance, mass spectrometry, infrared analysis, and ultraviolet spectrum, were showed.

Inhibitory and synergistic effects of natural olive phenols on human platelet aggregation and lipid peroxidation of microsomes from vitamin E-deficient rats.

Purpose: This study explored the in vitro antioxidant and anti-platelet activities of hydroxytyrosol, hydroxytyrosol acetate, 3,4-dihydroxyphenylglycol and two phenolic olive extracts. These compounds and extracts were obtained from a new industrial process to hydrothermally treat the alperujo (160 °C/60 min), a by-product of olive oil extraction.

Methods: The extracts and the purified compounds were obtained chromatographically using both ionic and adsorbent resins.

Properties of lignin, cellulose, and hemicelluloses isolated from olive cake and olive stones: binding of water, oil, bile acids, and glucose.

A process based on a steam explosion pretreatment and alkali solution post-treatment was applied to fractionate olive stones (whole and fragmented, without seeds) and olive cake into their main constitutive polymers of cellulose (C), hemicelluloses (H), and lignin (L) under optimal conditions for each fraction according to earlier works. The chemical characterization (chromatographic method and UV and IR spectroscopy) and the functional properties (water- and oil-holding capacities, bile acid binding, and glucose retardation index) of each fraction were analyzed. The in vitro studies showed a substantial bile acid binding activity in the fraction containing lignin from olive stones (L) and the alkaline extractable fraction from olive cake (Lp).

A study of the precursors of the natural antioxidant phenol 3,4-dihydroxyphenylglycol in olive oil waste.

3,4-Dihydroxyphenylglycol (DHPG) is a potent antioxidant recently found in the free form in olive oil and table olives. DHPG can be recovered from olive oil solid waste by a hydrothermal treatment. It was observed that an increase in the concentration of DHPG occurred when alperujo aqueous extracts were subjected to mild thermal conditions (post-treatment).

Isolation and identification of phenolic glucosides from thermally treated olive oil byproducts.

A liquid phase rich in bioactive compounds, such as phenols and sugars, is obtained from olive oil waste by novel thermal treatment. Two groups of fractions with common characteristics were obtained and studied after thermal treatment, acid hydrolysis, and separation by ultrafiltration, chromatography, and finally Superdex Peptide HR. In the first group, which eluted at the same time as oligosaccharides with a low DP (4-2), an oleosidic secoiridoid structure conjugated to a phenolic compound (hydroxytyrosol) was identified as oleuropeinic acid, and three possible structures were detected.

New phenolic compounds hydrothermally extracted from the olive oil byproduct alperujo and their antioxidative activities.

The application of a novel process based on the hydrothermal treatment of olive oil waste (alperujo) led to a final liquid phase that contained a high concentration of simple phenolic compounds. This study evaluated the effects of time (15-90 min) on the composition of the phenolic compounds isolated at a fixed temperature of 160 °C. Phenolic compounds were extracted with ethyl acetate.

New hydrothermal treatment of alperujo enhances the content of bioactive minor components in crude pomace olive oil.

The application of a new process based on the hydrothermal treatment of olive oil waste (alperujo) led to a final solid rich in pomace olive oil (POO) enriched in minor components with functional activities. The effects of the time (15-90 min) and the temperature (150, 160, and 170 °C) of the thermal processing of alperujo on the yield, quality, and enrichment of minor components of crude POO were evaluated. The final treated solid had an increase in oil yield up to 97%, with a reduction in solids up to 35.