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Objectives We aimed to assess the intralumenal stability of oleuropein in human gastric and small intestinal contents. We additionally aimed to assess the stability characteristics of oleuropein in media simulating the intralumenal conditions. Methods The intralumenal stability of oleuropein was assessed in aspirates from the stomach and the upper small intestine of healthy volunteers collected under both fasted and fed state conditions and in media simulating the intralumenal environment. Key findings Oleuropein degraded in aspirates collected in the fasted state. When the initial concentration was about 50 μg/ml (close to expected intragastric concentration after single dose of commercially available products of oleuropein) the mean zero-order half-life of oleuropein in aspirates collected from the fasted small intestine was estimated to be 3.14 ± 0.08 h at 37°C (i.e. after oral administration in the fasted state, a substantial fraction of oleuropein degrades before reaching the intestinal mucosa). In contrast, oleuropein was stable in aspirates collected from the fed stomach; in small intestinal contents aspirated in the fed state the estimated zero-order degradation half-life was at least 12 h. Conclusions These data suggest that oleuropein should not have substantial intralumenal stability problems when administered in the fed state. Data collected in media simulating the intragastric and intraintestinal environment suggest that pH affects the stability of oleuropein only at low pH values (of about 2). At higher pHs degradation characteristics are at least partly affected by the presence of other scavengers of reactive oxygen species in the medium.

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; This study was conducted to determine whether olive fruits, rich in micronutrients, might improve bone loss in ovariectomized (OVX) rats (an experimental model of postmenopausal osteoporosis) and in OVX rats with granulomatosis inflammation (a model of senile osteoporosis). Six-month-old Wistar female rats underwent ovariectomy and were then immediately treated orally by substituting oil in the diet by 10 g/d green Lucques olives or 6 g/d black Lucques olives for each rat for 84 days. OVX rats and sham-operated controls received the same diet with oil. Three weeks before the end of the experiment, subcutaneous inflammation was provoked by injections of sterile magnesium silicate in half the animals in each group. In OVX rats, granulomatosis inflammation, characterized by a rise in inflammatory parameters such as fibrinogen, alpha1-acid glycoprotein, spleen weight and granulocyte level, and an impairment of oxidative status (as shown by a decrease in plasma antioxidant capacity, a higher rate of isoprostane excretion) elicited a bone loss in the whole femur and in the metaphyseal areas considered on their own. Whereas green olives had no effect on osteopenia, consumption of the black variety prevented bone loss in the whole femur and at cortical sites in those oestrogen-deficient animals with talc inflammation (diaphyseal bone mineral density: black olives and inflammation 0-2323 (SE 0.0026) v. ovariectomy and inflammation 0.2117 (SE 0.0030); P=0.027). This bone-sparing effect seemed to result from an improvement in the inflammatory and oxidative status. The present data show that black olives are able to prevent bone loss in an experimental model of senile osteoporosis (oestrogen-deficient rats in which a low-grade inflammation was induced by talc injection).

Στην παρούσα διατριβή μελετήθηκαν φυτοχημικά τα φύλλα της Olea europaea cv. koroneiki και τα υγρά απόβλητα ελαιοτριβείων, απομονώθηκαν συνολικά 20 φυσικά προϊόντα και παρουσιάστηκαν αναλυτικά οι πορείες και τα αποτελέσματα. Η επιλογή των φύλλων και των υγρών αποβλήτων έγινε διότι αποτελούν παραπροϊόντα της ελαιουργίας αλλά ταυτόχρονα και πλούσια πηγή πολυφαινολικών ενώσεων. Επιγραμματικά στην παρούσα εργασία: Τα υγρά απόβλητα ελαιοτριβείων (κατσίγαρος) υποβλήθηκαν σε κατεργασία με ρητίνες προσρόφησης XAD16 και XAD7ΗΡ, με αποτέλεσμα την παραγωγή 2 κλασμάτων, ενός που ήταν εμπλουτισμένο σε πολυφαινόλες και ενός που περιείχε τις χρωστικές της ελιάς αντίστοιχα. Το κλάσμα που προέκυψε από την επεξεργασία των υγρών αποβλήτων με ρητίνη προσρόφησης XAD16 εισήλθε στους χρωματογραφικούς διαχωρισμούς. Απομονώθηκαν και ταυτοποιήθηκαν συνολικά 11 δευτερογενείς μεταβολίτες που κατατάσσονται σε 3 κατηγορίες φυσικών προϊόντων. Συγκεκριμένα, ανήκουν στα ιριδοειδή, φλαβονοειδή και φαινολικά παράγωγα Από τα απομονωθέντα μόρια, 2 αποτελούν νέα φυσικά προϊόντα. Πρόκειται για τον μεθυλεστέρα του 2-[5-αιθ-(Ε)-υλιδενο-2-οξο- τετραϋδροπυραν-4-υλ] ακρυλικού οξέος και τον μεθυλεστέρα του 1- μέθυλο-7-οξο-6,7,9,10-τετραϋδρο-1Η, 5Η-πυρανο[3,4-c]πυρανο-4- καρβοξυλικού οξέος Μελετήθηκε φυτοχημικά το ακετονικό εκχύλισμα των φύλλων της Olea europaea cv. koroneiki. Απομονώθηκαν και ταυτοποιήθηκαν συνολικά 9 δευτερογενείς μεταβολίτες που κατατάσσονται σε 4 κατηγορίες φυσικών προϊόντων. Συγκεκριμένα, ανήκουν στα ιριδοειδή, φλαβονοειδή, τριτερπένια και φαινολικά παράγωγα (φαινολικά οξέα, φαινυλαιθανόλες). Από τα απομονωθέντα μόρια, 1 απαντάται για πρώτη φορά στην Olea europaea. Πρόκειται για τον 8-επι-κινγκισίδη. Αναπτύχθηκε συνολικά μία διαδικασία υψηλής τεχνολογίας, αξιοποίησης των υγρών αποβλήτων των ελαιοτριβείων, κατά την οποία ανακτώνται οι φυσικές πολυφαινόλες και παράλληλα απομακρύνονται από το περιβάλλον χιλιάδες τόνοι υγρών αποβλήτων Αναπτύχθηκε κατάλληλη μεθοδολογία για την απομόνωση ολευρωπεΐνης, υδροξυτυροσόλης, λακτόνης και τυροσόλης σε βιομηχανικά κλίμακα. Μελετήθηκε η περιέκτικότητα των αφεψημάτων που προέρχονταν από τα φύλλα 10 διαφορετικών Ελληνικών καλλιεργούμενων ποικιλιών ελιάς σε ολευρωπεΐνη, ελενολικό οξύ, τυροσόλη και 5-(αιθυλιδενο-2-οξο- τετραϋδρο-πυρανυλ-4-) οξικό οξύ (Λακτόνη) και παρατηρήθηκαν σημαντικές διαφοροποιήσεις ανάμεσά τους. Πραγματοποιήθηκαν πειράματα σε κουνέλια in vivo όπου η ολευρωπεΐνη εμφάνισε σημαντική αντι-ισχαιμική, αντιοξειδωτική και υπολιπιδαιμική δράση Πραγματοποιήθηκαν πειράματα σε αρουραίους in vivo στα οποία παρατηρήθηκε δράση της ολευρωπεΐνης κατά της οστεοπόρωσης, ενώ εξετάστηκε και η πιθανότητα η δράση αυτή να είναι δοσοεξαρτόμενη.

Three new prostaglandins were isolated as minor constituents of the organic extract from the Caribbean soft coral Plexaura nina. The structures of the new natural products w ere established by means of spectral data analysis, including 2D NMR experiments. The unpalatability of the lipid extract of the coral and the defensive role of the major prostaglandin metabolites were determined by laboratory and field fish-feeding assays.

In search for compounds, able to protect nuclear DNA in cells exposed to oxidative stress, extracts from olive leaves, olive fruits, olive oil and olive mill waste water were tested by using the "single cell gel electrophoresis" methodology (comet assay). Jurkat cells in culture were exposed to continuously generated hydrogen peroxide (11.8+/-1.5 microM per min) by direct addition into the growth medium of the appropriate amount of the enzyme "glucose oxidase" in the presence or absence of the tested total extracts. The protective effects of the tested extracts or isolated compounds were evaluated from their ability to decrease hydrogen peroxide-induced formation of single strand breaks in the nuclear DNA, while the toxic effects were estimated from the increase of DNA damage when the extracts or isolated compounds were incubated directly with the cells. Significant protection was observed in extracts from olive oil and olive mill waste water. However, above a concentration of 100 microg/ml olive oil extracts exerted DNA damaging effects by themselves in the absence of any H2O2. Extracts from olive leaves and olive fruits although protective, were also able to induce DNA damage by themselves. Main compounds isolated from the above described total extracts, like oleuropein glucoside, tyrosol, hydroxytyrosol and caffeic acid, were tested in the same experimental system and found to exert cytotoxic (oleuropein glucoside), no effect (tyrosol) or protective effects (hydroxytyrosol and caffeic acid). In conclusion, cytoprotective as well as cytotoxic compounds with potential pharmaceutical properties were detected in extracts from olive oil related sources by using the comet assay methodology. Free Radic Res

The present study was designed to evaluate the effect of olive oil and its main polyphenol (oleuropein) in ovariectomised rats with or without inflammation. Rats (6 months old) were ovariectomised or sham-operated as control. Ovariectomised rats were separated into three groups receiving different diets for 3 months: a control diet with 25 g peanut oil and 25 g rapeseed oil/kg (OVX), the control diet with 50 g olive oil/kg or the control diet with 0·15 g oleuropein/kg. The sham-operated group was given the same control diet as OVX. Inflammation was induced 3 weeks before the end of the experiment by subcutaneous injections of talc (magnesium silicate) in one-half of each group. The sucess of ovariectomy was verified at necropsy by the atrophy of uterine horns. Inflammation, oleuropein or olive oil intakes did not have any uterotrophic activity, as they had had no effect on uterus weight. The plasma concentration of α-1-acid glycoprotein (an indicator of inflammation) was increased in OVX rats with inflammation. With regard to bone variables, osteopenia in OVX was exacerbated by inflammation, as shown by a decrease in metaphyseal and total femoral mineral density. Both oleuropein and olive oil prevented this bone loss in OVX rats with inflammation. At necropsy, oleuropein and olive oil consumption had had no effect on plasma osteocalcin concentrations (marker of bone formation) or on urinary deoxypyridinoline excretion (marker of bone resorption). In conclusion, oleuropein and olive-oil feeding can prevent inflammation-induced osteopenia in OVX rats.