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Purpose: Evaluate the efficacy of hydroxytyrosol in the local treatment of inflammatory colitis. Currently, the existing treatments for inflammatory bowel diseases does not cure the disease and it is associated with high rates of side effects and complications. Hydroxytyrosol is a phenyl-ethyl-alcohol derived from the hydrolysis of oleuropein and present in olive oil, previous studies have demonstrated the anti-inflammatory effect of dietary hydroxytyrosol supplement, with no toxicity. Materials & Methods: Colitis has been induced by using Trinitrobenzene Sulfonic Acid at 40 rats. They were divided into four groups randomly: 10 rats without treatment; 10 rats with pectin/alginate mixture; 10 rats treated with pectin/alginate + olive oil; 10 rats treated with pectin/alginate + olive oil + hydroxytyrosol. Animals were sacrificed 10 days after induction of trinitrobenzene sulfonic acid, receiving 5 days of continuous treatment. Samples of the rectal area were studied and observed under a microscope to determine the damage by Hunter scoring modified, assessing inflammatory infiltration, number of intestinal walls involved, damage to the mucosal architecture, and edema. Results: When the rectum was analyzed in a global way, nonsignificant differences were observed; however, when performing an individualized analysis, statistically significant differences in the inflammatory infiltrate are present in the samples, which were evaluated using the ANOVA and Student-T statistics. Conclusions: Local treatment with the natural antioxidant hydroxytyrosol combined with pectin/alginate and olive oil of inflammatory bowel disease has been shown to be effective against inflammatory infiltration of TNBS-induced colitis. [ABSTRACT FROM AUTHOR]

The Michael addition reactions of carbohydrate-derived nitroalkenes with ethyl thioglycolate and 2-mercaptobenzyl alcohol were studied. Reactions were conducted under mild, solvent-free conditions with DABCO as a catalyst, affording the corresponding adducts in good yields. Furthermore, compounds resulting from the addition with 2-mercaptobenzyl alcohol were used as starting materials for the synthesis of chiral 3-nitro-2H-thiochromenes. For some of the compounds synthesized herein, the antioxidant and antiproliferative activities against a panel of human solid tumor cell lines were assayed and compared with those of carbohydrate-nitroalkene substrates. [ABSTRACT FROM AUTHOR]

Lignin is the cell wall component most frequently associated with hardening. Its characterization and quantification are very important to understand the biochemical modifications related to the changes in texture of vegetables such as asparagus ( Asparagus officinalis), in which this organoleptic attribute is a very important quality factor. In this study, asparagus lignin from the basal sections of fresh and stored spears was analyzed using 2 methods, the traditional (Klason lignin) and the recently developed derivatization, followed by reductive cleavage (DFRC) method. The latter is a simple and reproducible technique for lignin characterization based on a degradation procedure that produces analyzable monomers and dimers by cleaving α- and β-aryl ethers in lignins. The primary monomers derived from DFRC degradation of lignins are essentially p-coumaryl peracetate, coniferyl peracetate, and sinapyl peracetate. To evaluate the efficiency of the DFRC method, our investigations have been carried on distinct sample types, including wood (data not shown), straw, and asparagus samples. The results have confirmed that lignin composition is affected by plant nature. It has been found that whereas wood samples mostly contain coniferyl units, plant foods, such as straw and asparagus, contain both coniferyl and guaiacyl units. [ABSTRACT FROM AUTHOR]

Olive cake was processed by steam-explosion under different steam conditions, followed by fractionation to separate the main components. In the water-soluble fraction, the main compounds were carbohydrates. Glucose represented a significant part of the total monosaccharide content, especially under conditions of mild severity, followed by arabinose, but the solubilization of sugars occurred predominantly in the oligomeric fraction. Mannitol was also found in significant amounts (1.5%), similar to that in the initial material. In the ethyl acetate extract, low molecular weight phenols were identified, the most aboundant being hydroxytyrosol, which is present in the olive pulp. Hydroxytyrosol is abundant and has great antioxidant activity, reaching 149 mg/100 g of dry olive cake. The procedure used in this study obtained all the hydroxytyrosol residual present in the by-product. The constitutive polymers were quantified in the insoluble fraction, and the sugar composition showed that cellulose was associated with a high proportion of xylans and other polysaccharides rich in arabinose and galactose. This cellulose was nearly amorphous, as it was highly susceptible to hydrolytic enzymes. The extractables in dilute alkali (not true lignins) increased as steaming became more severe; the residual “lignin” in this fraction decreased. Enzymatic hydrolysis of the insoluble fraction using a cellulolytic complex was also studied. The slight increase in the extent of saccharification was not proportional to the high alkaline delignification. However, when the residues were efficiently delignified with chlorite treatment, the susceptibility to enzymatic hydrolysis greatly increased. [ABSTRACT FROM AUTHOR]

The lignocellulosic by-products, whole stones, and seed husks obtained from processing pitted table olives and oil olives were pretreated under various conditions of steam explosion, with and without previous acid impregnation. The various water-soluble noncarbohydrate compounds generated during steam explosion, such as sugar degradation compounds (furfural and hydroxymethylfurfural), lignin degradation compounds (vanillic acid, syringic acid, vanillin, and syringaldehyde) and the simple phenolic compounds characteristic of olive fruit (tyrosol and hydroxytyrosol), were identified. The amount of hydroxytyrosol solubilized was higher than that of the other compounds, and increased with increasing steaming temperature and time. This suggests its presence as a structural component of the olive stone. [ABSTRACT FROM AUTHOR]