Phytosterols in grapes and wine,and effects of agrochemicals on their levels

To improve the knowledge on the chemical diversity and complexity of grapevine, we investigated the plant sterol content of berry and seed tissues at pre-véraison and véraison stages in 2009 and 2010. We also assessed the effects of benzothiadiazole and chitosan elicitors on content of sterols in grapes and their levels in the corresponding experimental wines. β-Sitosterol was the most abundant component in berry tissues, in both growth stages and years, with the highest amounts in the flesh and skin at pre-véraison and véraison, respectively. Stigmasterol and campesterol were present in lower concentrations in both phenological stages and vintages. During the transition from pre-véraison to véraison, phytosterols decreased in all tissues, in both years, apart from stigmasterol in seeds. In addition, the results showed that the plant activators were more effective than conventional fungicides in rising the levels of sterols, particularly β-sitosterol, both in grapes and in microvinificates.     

Just Noticeable Differences and Weber Fraction of Oral Thickness Perception of Model Beverages

Rheological properties of beverages contribute considerably to texture perception. When developing new beverages, it is important to have knowledge on the smallest differences of viscosity which a consumer can discriminate. Thickness is the sensory attribute most commonly used to describe the viscosity of beverages. The aim of this study was to determine the Just Noticeable Differences (JNDs) of oral thickness perception and the Weber fraction (K) of Newtonian model stimuli (maltodextrin solutions). JNDs were determined using the method of constant stimuli with 5 reference stimuli ranging in viscosity from 10 to 100 mPa?s. JNDs increased with increasing viscosity of the reference stimulus. The Weber fraction (K) for oral thickness perception of model beverages was K = 0.26 for the studied viscosity range. The Weber fraction for oral thickness perception is comparable to Weber fractions reported in literature for perception of kinesthetic food firmness and spreadability, creaminess, sourness, and bitterness perception. This demonstrates that the human sensitivity towards oral discrimination of thickness of liquid stimuli is comparable to the human sensitivity towards discrimination of specific texture properties and specific taste stimuli.     

Research funding for psychology.

Describes recent trends in funding for basic and applied research in psychology. Comparisons are made with other disciplines and in relation to available manpower. Data that bear on research costs, proposals funded, research quality, and support for young vs senior psychologists are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

HPLC-ESI-MS/MS assessment of the tetrahydro-metabolites of cortisol and cortisone in bovine urine: promising markers of dexamethasone and prednisolone treatment

The effects of long-term administration of low doses of dexamethasone (DX) and prednisolone (PL) on the metabolism of endogenous corticosteroids were investigated in veal calves. In addition to cortisol (F) and cortisone (E), whose interconversion is regulated by 11β-hydroxysteroid dehydrogenases (11βHSDs), special attention was paid to tetrahydrocortisol (THF), allo-tetrahydrocortisol (aTHF), tetrahydrocortisone (THE) and allo-tetrahydrocortisone (aTHE), which are produced from F and E by catalytic activity of 5α and 5β-reductases. A specifically developed HPLC-ESI-MS/MS method achieved the complete chromatographic separation of two pairs of diastereoisomers (THF/aTHF and THE/aTHE), which, with appropriate mass fragmentation patterns, provided an unambiguous conformation. The method was linear (r² > 0.9905; 0.5–25 ng ml^?1), with LOQQ of 0.5 ng ml^?1. Recoveries were in range 75–114%, while matrix effects were minimal. The experimental study was carried out on three groups of male Friesian veal calves: group PL (n = 6, PL acetate 15 mg day^–1 p.o. for 31 days); group DX (n = 5, 5 mg of estradiol (E2) i.m., weekly, and 0.4 mg day^–1 of DX p.o. for 31 days) and a control group (n = 8). Urine was collected before, during (twice) and at the end of treatment. During PL administration, the tetrahydro-metabolite levels decreased gradually and remained low after the suspension of treatment. DX reduced urinary THF that persisted after the treatment, while THE levels decreased during the experiment, but rebounded substantially after the DX was withdrawn. Both DX and PL significantly interfered with the production of F and E, leading to their complete depletion. Taken together, the results demonstrate the influence of DX and PL administration on 11βHSD activity and their impact on dysfunction of the 5-reductase pathway. In conclusion, profiling tetrahydro-metabolites of F and E might serve as an alternative, indirect but reliable, non-invasive procedure for assessing the impact of synthetic glucocorticosteroids administration.     

Therapeutic and nutraceutical potential of rosmarinic acid—Cytoprotective properties and pharmacokinetic profile

Rosmarinic acid (RA) is a natural polyphenolic antioxidant derived from many common herbal plants. This compound displays several important biological properties, including anti-inflammatory, antiviral, antibacterial, antidepressant, anticarcionogenic, and chemopreventive properties. The importance of its activities and its possible application in processed foods as a natural antioxidant has reached a new interest levels in recent years. The health effects of this polyphenol depend greatly on both its intakes and bioavailability. This review focuses on the importance of RA as a dietary supplement, and summarizes its pharmacokinetics and metabolism, including the factors that limit its oral bioavailability which leads to a lower therapeutic action. Further experimental investigations are needed to optimize and enhance the oral bioavailability of this natural compound which consequently will help increasing therapeutic efficacy of RA in vivo.     

Food and feed components for gut health‐promoting adhesion of E. coli and Salmonella enterica

BACKGROUND: A host runs less risk of contracting a gastrointestinal infection when enteropathogenic bacteria adhere to dietary fibers instead of to epithelial cell receptors. The aim of this study was to test the binding capacity of food and feed components for intestinal bacteria from various hosts using a miniaturized in vitro assay. In total, 18 dietary components were tested with four strains of E. coli, seven strains of Salmonella enterica and two strains of Lactobacillus. RESULTS: A comparison of the results obtained for all Salmonella strains tested revealed that konjac gum and sesame seed extract represented the most efficient binding matrices. Similarly, for all E. coli strains tested, sesame seed extract and artichoke performed well as binding matrices. Salmonella isolates from chickens adhered best to sesame seed extract. E. coli K88 and S. enterica sv. Typhimurium isolated from pigs effectively bound to BioMos®, pumpkin, sesame seed extract, and tomato. Sesame seed extract and tomato also had adhesive capacities for E. coli K 99, S. enterica sv. Dublin, and S. enterica sv. Typhimurium from calves. With human isolates, konjac gum showed a high binding potential for S. enterica and E. coli. CONCLUSION: The adhesion screening of different food and feed components resulted in highly discriminating product rankings. Copyright © 2008 Society of Chemical Industry     

Analysis of volatile components of fruits by HS‐PTV‐GC

A method for the analysis of fruit headspace using a programmed temperature vaporiser (PTV) gas chromatographic injector as an intermediate trap is proposed. The method consists of a purge of the volatile compounds into the PTV glass‐liner filled with a packing material of high surface area. The trapped compounds are thermally desorbed in the PTV injector and transferred to the gas chromatographic column. The variables that influence the extraction and transfer processes have been optimised for fruit flavour analysis. Examples of the application of the method to the analysis of bananas, blackberries and raspberries are given. © 1999 Society of Chemical Industry     

The nutraceutical value of grain legumes: characterisation of bioactives and antinutritionals related to diabesity management

Beyond the nutritional value, legumes and particularly common beans are found in several dietary supplements used to treat diabesity (diabetes and obesity). These products contain not only inhibitors of carbohydrate-hydrolising enzymes (α-amylase, α-glucosidase), but also antinutritional factors that can cause adverse effects on human health. In the present research, twenty-two accessions of grain legumes were screened for bioactive (α-amylase and α-glucosidase inhibitors) and antinutritional (lectins, flatulence-producing sugars, trypsin inhibitors) phytochemicals. Results showed that four accessions had high α-amylase inhibiting activities (AI > 30%), and particularly the common bean ‘Great Northern’ resulted of interest for its high carbo-blocker activity (AI = 42.6 ± 0.5%), absence of lectins, low amounts of flatulence-producing oligosaccharides (2.5 ± 0.2 g/100 g DW) and low anti-trypsin activity (22.5 ± 4.3 trypsin inhibiting unit/mg DW). The knowledge offered from this work provides leads to the ultimate goal of developing new, more effective and safer dietary supplements for diabesity management.