Effects of olive and pomegranate by-products on human microbiota : a study using the SHIME (R) in vitro simulator

Two by-products containing phenols and polysaccharides, a "pate" (OP) from the extra virgin olive oil milling process and a decoction of pomegranate mesocarp (PM), were investigated for their effects on human microbiota using the SHIME (R) system. The ability of these products to modulate the microbial community was studied simulating a daily intake for nine days. Microbial functionality, investigated in terms of short chain fatty acids (SCFA) and NH4+, was stable during the treatment. A significant increase in Lactobacillaceae and Bifidobacteriaceae at nine days was induced by OP mainly in the proximal tract. Polyphenol metabolism indicated the formation of tyrosol from OP mainly in the distal tract, while urolithins C and A were produced from PM, identifying the human donor as a metabotype A. The results confirm the SHIME (R) system as a suitable in vitro tool to preliminarily investigate interactions between complex botanicals and human microbiota before undertaking more challenging human studies

Olive-oil Phenolics and Health: Potential Biological Properties

Extra virgin olive oil, the primary source of oil in the Mediterranean diet, differs significantly in composition from dietary lipids that are consumed by other populations. The several minor constituents of virgin olive oil include vitamins such as alpha-and gamma-tocopherols (around 200 ppm) and beta-carotene, phytosterols, pigments, terpenic acids, flavonoids, squalene, and a number of phenolic compounds, such as hydroxytyrosol, usually grouped under the rubric "polyphenols". The antioxidant and enzyme-modulating activities of extra virgin olive oil phenolics, such as their ability to inhibit NF-kB activation in human monocyte/macrophages has been demonstrated in vitro. There is also solid evidence that extra virgin olive oil phenolic compounds are absorbed and their human metabolism has been elucidated. Several activities that might be associated with cardiovascular protection, such as inhibition of platelet aggregation and reduction of plasma rHcy have been demonstrated in vivo. The biologically relevant properties of olive phenolics are described, although further investigations in controlled clinical trials are needed to support the hypothesis that virgin olive oil consumption may contribute to lower cardiovascular mortality

Phenolic Profiles of Four Processed Tropical Green Leafy Vegetables Commonly Used as Food

The phenolic profiles are presented of four tropical green leafy vegetables ( Ocimum gratissimum, Vernonia amygdalina, Corchorus olitorius and Manihot utilissima) commonly used as food, after application of traditional treatments, such as boiling and abrasion. The HPLC/DAD/MS technique was mainly used to carry out this study. Preliminary evaluation of the antioxidant properties of the vegetables was also performed using the DPPH in vitro test. For the first time, seasonal variations in the phenolic content of the four investigated vegetables were highlighted. Of the four plants, all showed only quantitative differences, except for Ocimum graticimum, in which cichoric acid, previously detected as one of the main constituents of this vegetable collected in November (dry season), was absent in the sample harvested in March. The phenolic constituents are chemically unmodified after a strong heating process, such as the traditional blanching (about 15 minutes) applied by Nigerian people prior to consuming these vegetables. Nevertheless, these typical preparations showed a consistent decrease in the total phenolic compounds with respect to the raw material, particularly for Corchorus olitorius (from 42.3 to 5.56 mg/g dried leaves) and Vernonia amygdalina (from 40.2 to 4.4 mg/g dried leaves). As expected, when the blanching treatment is reduced to a few minutes, as for Manihot utilissima leaves, the cooked vegetable maintained almost unaltered its original phenolic content (around 10 mg/g dried leaves). The unique exception is the blanched Ocimum gratissimum sample that showed a consistent increment of the total phenols, particularly of rosmarinic acid (from 6.1 to 29.8 mg/g dried leaves) with respect to the unprocessed vegetable

New isobaric lignans from refined olive oils as quality markers for virgin olive oils.

Herein we describe the influence of olive oil refining processes on the lignan profile. The detection of new isobaric lignans is suggested to reveal frauds in commercial extra-Virgin Olive Oils. We analyzed five commercial olive oils by HPLC-DAD-TOF/MS to evaluate their lignan content and detected, for the first time, some isobaric forms of natural (+)-pinoresinol and (+)-1-acetoxypinoresinol. Then we analyzed partially and fully-refined oils from Italy, Tunisia and Spain. The isobaric forms occur only during the bleaching step of the refining process and remain unaltered after the final deodorizing step. Molecular dynamic simulation helped to identify the most probable chemical structures corresponding to these new isobars with data in agreement with the chromatographic findings. The total lignan amounts in commercial olive oils was close to 2 mg/L. Detection of these new lignans can be used as marker of undeclared refining procedures in commercial extra-virgin and/or Virgin Olive Oils

A New Extract from Pomegranate (Punica granatum L.) By-Products as a Potential Oenological Tannin: Preliminary Characterization and Comparison with Existing Commercial Products

Oenotannins are nowadays widely used as co-adjuvant in the winemaking process. The increasing cultivation and consumption of pomegranate (Punica granatum L.) leads to high amounts of by-products, mainly peels. Aim of this study was to propose a dried tannin-rich extract from pomegranate by-products as a new oenotannin. A decoction was prepared from mesocarp of the Wonderful pomegranate variety only using hot water as extracting solvent. The dried decoction was physical-chemically characterized and compared to 7 existing commercial oenotannins from different botanical origin (grape seed, oak, gallnut), according to UV-Vis Spectroscopy, Colorimetric analysis (CIELab), gelatin index, reactivity to proteins, HPLC-DAD, DPPH, and Total Polyphenols content by both Folin-Ciocalteu and the International Organization of Vine and Wine (OIV) methods. Data showed the lowest antiradical (AR) and total polyphenolic content (TPC) for the pomegranate tannin but also the highest AR/TPC ratio suggesting a good radical scavenging potential of this new tannin. Pomegranate tannin showed high reactivity with proteins, a unique chromatographic profile, and a low color impact. The new pomegranate tannin showed an interesting potential for oenological applications in particular for reducing the use of sulfites during vinification and for the white wine stabilization