Is food preference innate instinct driven or human's free will?

The question whether food preference decisions are controlled by innate instincts, or a conscious decision-making process is still open. The answer to this question is important not only for neuroscientists, psychologists, and philosophers but also for food scientists and developers. Looking from different perspectives involved in food preference decisions could not only settle a long ongoing debate but also pave the way to understand why people prefer to eat what they eat.

Anti-Amyloid Aggregation Activity of Black Sesame Pigment: Toward a Novel Alzheimer's Disease Preventive Agent.

Black sesame pigment (BSP) represents a low cost, easily accessible material of plant origin exhibiting marked antioxidant and heavy metal-binding properties with potential as a food supplement. We report herein the inhibitory properties of the potentially bioaccessible fraction of BSP following simulated gastrointestinal digestion against key enzymes involved in Alzheimer's disease (AD). HPLC analysis indicated that BSP is transformed under the pH conditions mimicking the intestinal environment and the most abundant of the released compounds was identified as vanillic acid. More than 80% inhibition of acetylcholinesterase-induced aggregation of the ß-amyloid Aß1-40 was observed in the presence of the potentially bioaccessible fraction of BSP, which also efficiently inhibited self-induced Aß1-42 aggregation and ß-secretase (BACE-1) activity, even at high dilution. These properties open new perspectives toward the use of BSP as an ingredient of functional food or as a food supplement for the prevention of AD.

Chemical composition and inhibitory activities on dipeptidyl peptidase IV and pancreatic lipase of two underutilized species from the Brazilian Savannah: Oxalis cordata A.St.-Hil. and Xylopia aromatica (Lam.) Mart.

Brazil has the greatest vegetal biodiversity in the world, but products derived from native species are not optimally utilized. Oxalis cordata and Xylopia aromatica are two underutilized species whose leaves and fruits, respectively, have been used as food in the 19th century. In this study, we used chemical and in vitro assays to evaluate the potential of these species as functional foods. The inhibitory activity on pancreatic lipase and DPP-IV were evaluated using the crude extracts and fractions ethyl acetate, butanol and water of these two species. For polyphenols determination, samples were prepared with different solvents and these were analysed by chromatographic and spectroscopic methods. Finally, fatty acids profile was determinated by gas chromatography. The crude extract (IC50=0.84mg/ml), ethyl acetate extract (IC50=0.88mg/ml) an aqueous fraction (IC50=0.63mg/ml) of C. cordata were inhibitory on pancreatic lipase but inactive against dipeptidyl peptidase IV (DPP-IV). Extracts from X. aromatica were inactive against the lipase pancreatic enzyme, but a butanolic fraction inhibited DPP-IV (IC50=0.71±0.05mg/ml). The phenolic acids orientin/isorientin, chlorogenic acid (0.32g/100g) and the flavonoid derivatives rutin (0.27g/100g), quercetin and luteolin were observed in all products. Additionally, fatty acid quantification showed that oleic (7.5g/100g) and linoleic acid (6.5g/100g) were predominant in X. aromatica fruit. This study confirms the potential for the use of both plants as functional foods due to their nutritional value, biological activity and important phytochemical content.

Epilutein for Early-Stage Age-Related Macular Degeneration: A Randomized and Prospective Study.

PURPOSE: The hypothesis that oral supplementation of the epilutein/lutein combination could augment the macular pigment optical density (MPOD) in patients with age-related macular degeneration (AMD) was tested. METHODS: In a prospective randomized interventional study, 40 consecutive patients with early-stage AMD were recruited. After a 2-week run-in period, patients were randomly treated with a daily oral administration of 8 mg epilutein and 2 mg lutein (group 1) or 10 mg lutein (group 2) for 2 months. At baseline (BL) and 1-month (M1) and 2-month visits (M2), all patients underwent a complete ophthalmological examination, including measurement of MPOD in a 7° area (Visucam 200; Carl Zeiss Meditec, Milan, Italy). Xanthophylls were quantified in plasma, as well as the HDL, non-HDL, and erythrocyte fractions at each study visit. RESULTS: Twenty-one patients (mean age 69.4 ± 6.7 years, 35 eyes) were included in group 1. Mean MPOD was 0.203 ± 0.02 optical density units (ODU) at BL, and increased to 0.214 ± 0.04 ODU at M1 (p = 0.008) and 0.206 ± 0.03 ODU at M2 (p = 0.04). Sixteen patients (mean age 72.0 ± 6.3 years, 29 eyes) were included in group 2. Mean MPOD was 0.215 ± 0.03 at BL, which reduced to 0.202 ± 0.03 ODU at M1 (p = 0.003) and 0.207 ± 0.02 ODU at M2 (p < 0.001). A rise in the systemic level of total xanthophylls was observed at M1 for both groups. At M2, total xanthophylls were significantly increased only in group 1 and decreased in group 2. CONCLUSION: In patients with early-stage AMD, the administration of lutein in combination with epilutein was associated with an increased MPOD compared to the administration of lutein alone.

Efficient Binding of Heavy Metals by Black Sesame Pigment: Toward Innovative Dietary Strategies To Prevent Bioaccumulation.

Black sesame pigment (BSP) was shown to bind lead, cadmium, and mercury at pH 7.0 and to a lower extent at pH 2.0. BSP at 0.05 mg/mL removed the metals at 15 µM to a significant extent (>65% for cadmium and >90% for mercury and lead), with no changes following simulated digestion. The maximum binding capacities at pH 7.0 were 626.0 mg/g (lead), 42.2 mg/g (cadmium), and 69.3 mg/g (mercury). In the presence of essential metals, such as iron, calcium, and zinc, BSP retained high selectivity toward heavy metals. Model pigments from caffeic acid, ferulic acid, and coniferyl alcohol showed lower or comparable binding ability, suggesting that the marked properties of BSP may result from cooperativity of different sites likely carboxy groups and o-diphenol and guaiacyl functionalities. Direct evidence for the presence of such units was obtained by structural analysis of BSP by solid-state Fourier transform infrared spectroscopy and (13)C nuclear magnetic resonance spectroscopy.

Inhibition of dipeptidyl peptidase activity by flavonol glycosides of guava (Psidium guajava L.): a key to the beneficial effects of guava in type II diabetes mellitus.

Based on the traditional use in popular medicine, the effect of extracts from Psidium guajava L. leaves and of the main flavonol-glycoside components on dipeptidyl-peptidase IV (DP-IV), a key enzyme of blood glucose homoeostasis, has been investigated in-vitro. An ethanolic extract was prepared from dried, powdered leaves of guava and was found to contain seven main flavonol-glycosides, which were isolated by semipreparative HPLC and tested individually. The ethanolic guava leave extract was shown to exert a dose-dependent inhibition of DP-IV, with an IC50 of 380 µg/ml test assay solution. Also the individual flavonol-glycosides inhibited DP-IV dose-dependently, with variations of the effects by a factor of 10, and an overall effect accounting for 100% of that observed for the total guava extract. The recovery of individual flavonol-glycosides in CaCo-2 epithelial cells, a model of gastrointestinal tract absorption, amounted to 2.3-5.3% of the amount available for absorption over 60 min at 37°C.

Black sesame pigment: DPPH assay-guided purification, antioxidant/antinitrosating properties, and identification of a degradative structural marker.

An improved purification procedure leading to black sesame ( Sesamum Indicum L.) pigment was developed involving fat removal by treatment of ground black sesame seeds with dichloromethane followed by an optimized hydrolytic protocol with 6 M HCl, at 100 °C, overnight. The black pigment thus obtained displayed good antioxidant efficiency by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical assay (82% reduction at 0.5 mg/mL), good ferric ion-reducing capacity (61 µM Trolox equivalent concentration at 0.5 mg/mL), and potent antinitrosating properties (74% inhibition of 2,3-diaminonaphthalene (DAN) nitrosation at gastric pH at 2.5 mg/mL). A synthetic pigment obtained by oxidative polymerization of coniferyl alcohol (polyconiferyl alcohol, PCA), the putative biosynthetic precursor to the sesame pigment, was characterized as a reference standard. FT IR spectra of the purified sesame pigment and PCA supported the structural similarity. HPLC analysis of degradation products by alkaline hydrogen peroxide of purified black sesame pigment showed the formation of vanillic acid (VA) as the main isolable fragment. Similar yields of VA were obtained by degradation of PCA. A positive correlation between VA yields and DPPH activity was determined in samples of different purities. It is suggested that VA is a structural marker of black sesame pigment, confirming the biosynthetic origin from coniferyl alcohol and pointing to the o-methoxyphenol motif as the key factor accounting for the potent antioxidant properties of the pigment.