Activities, bioavailability, and metabolism of lipids from structural membranes and oils: Promising research on mild cognitive impairment.

Concomitant with increased lifespan, large segments of the population are experiencing cognitive decline, which might progress to Alzheimer's disease (AD). Currently, there is no cure for AD and, once the neurodegenerative disorders are established, patients use pharmacologic therapy to slow the progression of the symptoms and require appropriate care to manage their condition. The preclinical stage of neural degeneration that progress through mild cognitive impairment (MCI) before the onset of AD is when it might be possible to introduce behavioral changes and pharma-nutritional interventions that modify the risk factors of MCI conversion to AD. Some food components accumulate in brain tissues, where they play essential roles. Among them, polar lipids, omega 3 fatty acids, and carotenoids appear to work additively or synergistically. Therefore, there is an opportunity to formulate nutraceuticals/functional foods to slow the progression of MCI. In this paper, we review the biochemical bases and recent interventions with bioactive lipids-rich formulations. Based on accumulated evidence, we propose that appropriate large-scale trials are warranted.

Xanthophyll esters are found in human colostrum.

SCOPE: Carotenoids in human milk are associated with other lipid counterparts in several metabolic processes. One interesting association that has not been demonstrated to date is the presence of xanthophyll esters. Colostrum and mature milk samples were analyzed to determine the occurrence of xanthophyll esters and identify the compounds. Thus, the association of the amounts of these compounds with lactation and whether they are significant contributors to the carotenoid profile of human milk was assessed. METHODS AND RESULTS: Pre-term and term delivering mothers were included in the study to donate colostrum at 3-5 days postpartum and mature milk at 15 days postpartum. Carotenoids extracts were subjected to a clean-up procedure to remove the triacylglycerol fraction and then analyzed by HPLC-MSn . Identification of xanthophyll esters was achieved by considering their chromatographic behaviour, UV-visible characteristics and MSn features. CONCLUSION: Xanthophyll esters are significant contributors to the carotenoid profile in the colostrum, while mature milk does not contain these compounds. Therefore, fatty acid acylation to xanthophylls is activated during the accumulation of carotenoids in the human mammary gland. The sharp decline in the amount of xanthophyll esters in mature milk indicates that the lipophilic components are those recently incorporated in the mammary epithelium.

Picrocrocin kinetics in aqueous saffron spice extracts (Crocus sativus L.) upon thermal treatment.

The kinetics of picrocrocin degradation in aqueous extracts of saffron upon thermal treatment from 5 to 70 °C have been studied, together with the degradation of purified picrocrocin in water at 100 °C. The best fits to experimental data were found for a second-order kinetics model. Picrocrocin showed high stability with half-life periods (t(1/2)) ranging from >3400 h at 5 °C in saffron extracts to 9 h in the experiments with purified picrocrocin at 100 °C. In saffron extracts, the evolution of the rate constant (k) with temperature showed maximum values at 35 °C, and filtration of the extracts contributed to picrocrocin stability. In the case of purified picrocrocin, the generation of safranal in the first 5 h (yield up to 7.4%) was confirmed. Spectrometric parameters used in saffron quality control (E(1cm)(1%) 257 nm and ΔΕ(pic)) were not appropriate for documenting the evolution of picrocrocin.

Effects of maternal carotenoid availability in relation to sex, parasite infection and health status of nestling kestrels (Falco tinnunculus).

Mothers can strongly influence the development of their offspring, and if maternal resources are limited, they may influence optimal reproductive strategies. In birds, maternally deposited carotenoids are a prominent component of egg yolk and are vital for the development of the embryo. However, results of long-lasting fitness consequences of this early nutritional environment have been scarce and inconsistent. In addition, sex-biased sensitivity to different egg components is one of the mechanisms postulated to account for sex-linked environmental vulnerability during early life. However, this important aspect is usually not accounted for when investigating maternal investment in carotenoids. In this study we gave carotenoid (lutein) supplements to female Eurasian kestrels (Falco tinnunculus) before and during egg laying. The experiment increased female plasma carotenoids, but this effect was not apparent in hatchling and fledgling plasma carotenoid concentration. Also, results showed that carotenoid supplementation increased the high density lipoprotein to low density lipoprotein ratio in adult females, suggesting that dietary carotenoids may influence lipid metabolism. Furthermore, the effect of the treatment was manifested in several nestling health state parameters. Nestlings of carotenoid-supplemented females were infested by less intestinal parasite groups, had higher lymphocyte concentrations in blood plasma, and were less stressed (heterophile to lymphocyte ratio) than control nestlings. In addition, an interaction between the experimental treatment and nestling sex was apparent for globulin concentrations, favouring the smaller male nestlings. Thereby, suggesting that males benefited more than females from an increase in maternal carotenoid investment. Our study shows that an increase in carotenoids in the maternal diet during egg laying favours nestling development in kestrels, and may also affect nestlings in a sex-specific way.

Characterization of polyphenol oxidase from the Manzanilla cultivar (Olea europaea pomiformis) and prevention of browning reactions in bruised olive fruits.

The crude extract of the polyphenol oxidase (PPO) enzyme from the Manzanilla cultivar (Olea europaea pomiformis) was obtained, and its properties were characterized. The browning reaction followed a zero-order kinetic model. Its maximum activity was at pH 6.0. This activity was completely inhibited at a pH below 3.0 regardless of temperature; however, in alkaline conditions, pH inhibition depended on temperature and was observed at values above 9.0 and 11.0 at 8 and 25 degrees C, respectively. The thermodynamic parameters of substrate oxidation depended on pH within the range in which activity was observed. The reaction occurred according to an isokinetic system because pH affected the enzymatic reaction rate but not the energy required to carry out the reaction. In the alkaline pH region, browning was due to a combination of enzymatic and nonenzymatic reactions that occurred in parallel. These results correlated well with the browning behavior observed in intentionally bruised fruits at different temperatures and in different storage solutions. The use of a low temperature ( approximately 8 degrees C) was very effective for preventing browning regardless of the cover solution used.

Pigment-lipoprotein complexes in table olives (Cv. Gordal) with green staining alteration.

In table olives showing the green staining alteration, extracts of pigment-lipoprotein complexes were obtained from the zone altered and the rest of the fruit. In the altered zone of the olive, the surrounding components of pigments were affected, with the degeneration of proteins and phospholipids forming the pigment-lipoprotein complexes. There was also less interaction between the pigments and the membrane lipids. These results suggested a greater loss of cell integrity in the green-stained zone of the fruit, allowing the migration and local accumulation of Cu-metallochlorophyll complexes, macroscopically visible as the form of green staining alteration.

Differences in the activity of superoxide dismutase, polyphenol oxidase and Cu-Zn content in the fruits of Gordal and Manzanilla olive varieties.

Activity of the enzymes superoxide dismutase (SOD) and polyphenol oxidase (PPO) as well as Cu-Zn content have been monitored during the thirteen weeks growth of both Gordal and Manzanilla olive variety fruits. These metalloenzymes, with Cu and Zn in the prostetic group, are involved in controlling the redox balance in the chloroplast environment. The results indicated that, under similar phenological and environmental conditions, there are periodic peaks of SOD activity in both varieties, followed by fluctuations in the copper content of the fruit. This was interpreted as a common and simultaneous response to situations of oxidative stress, and this response was more intense in the variety Gordal. The enzyme PPO showed an activity peak at start of growth and then practically disappeared. Thus, its activity cannot be correlated with situations of stress or with changes of Cu and Zn in the fruit.