Pectin Influences the Absorption and Metabolism of Polyphenols from Blackcurrant and Green Tea in Rats.

Consumption of polyphenols and dietary fiber as part of a normal diet is beneficial to human health. In this study, we examined whether different amounts of dietary soluble fiber (pectin) affect the absorption and metabolism of polyphenols from blackcurrant and green tea in rats. After 28 days, the rats fed blackcurrant and green tea with pectin (4 or 8%) had significantly lower body weight gain and food intake compared to the rats fed a control diet.

Composition and safety evaluation of tea from New Zealand kawakawa (Piper excelsum).

Kawakawa (Piper excelsum) has food, medicinal and cultural importance to the indigenous Māori people of New Zealand, and is being incorporated into a range of commercial food and therapeutic products, including tea. In this study, the chemical compositions of kawakawa fresh leaves, dried leaves for tea, and hot brewed tea, were analysed and compared. The key metabolites were diayangambin, elemicin, myristicin, unidentified lignans and amides.

Glycosides of the Neurotoxin Tutin in Toxic Honeys Are from Coriaria arborea Phloem Sap, Not Insect Metabolism.

Some honeys contain the neurotoxin tutin (1) plus hyenanchin (2), 2-(β-d-glucopyranosyl)tutin (3), and 2-[6'-(α-d-glucopyranosyl)-β-d-glucopyranosyl]tutin (4). These honeys are made by bees collecting honeydew from passionvine hoppers feeding on the sap of tutu plants ( Coriaria spp.).

Selenium treatment differentially affects sulfur metabolism in high and low glucosinolate producing cultivars of broccoli (Brassica oleracea L.).

The effect of selenium (Se) application on the sulfur (S)-rich glucosinolate (GSL)-containing plant, broccoli (Brassica oleracea L. var. italica) was examined with a view to producing germplasm with increased Se and GSL content for human health, and to understanding the influence of Se on the regulation of GSL production.

Sweet Poisons: Honeys Contaminated with Glycosides of the Neurotoxin Tutin.

Poisonings due to consumption of honeys containing plant toxins have been reported widely. One cause is the neurotoxin tutin, an oxygenated sesquiterpene picrotoxane, traced back to honeybees (Apis mellifera) collecting honeydew produced by passionvine hoppers (Scolypopa australis) feeding on sap of the poisonous shrub tutu (Coriaria spp.).

Starch phosphorylation in potato tubers is influenced by allelic variation in the genes encoding glucan water dikinase, starch branching enzymes I and II, and starch synthase III.

Starch phosphorylation is an important aspect of plant metabolism due to its role in starch degradation. Moreover, the degree of phosphorylation of starch determines its physicochemical properties and is therefore relevant for industrial uses of starch. Currently, starch is chemically phosphorylated to increase viscosity and paste stability.

Flavor, glucosinolates, and isothiocyanates of nau (Cook's scurvy grass, Lepidium oleraceum) and other rare New Zealand Lepidium species.

The traditionally consumed New Zealand native plant nau, Cook's scurvy grass, Lepidium oleraceum, has a pungent wasabi-like taste, with potential for development as a flavor ingredient. The main glucosinolate in this Brassicaceae was identified by LC-MS and NMR spectroscopy as 3-butenyl glucosinolate (gluconapin, 7-22 mg/g DM in leaves). The leaves were treated to mimic chewing, and the headspace was analyzed by solid-phase microextraction and GC-MS.

Inhibition of platelet activation by lachrymatory factor synthase (LFS)-silenced (tearless) onion juice.

Onion and garlic are renowned for their roles as functional foods. The health benefits of garlic are attributed to di-2-propenyl thiosulfinate (allicin), a sulfur compound found in disrupted garlic but not found in disrupted onion. Recently, onions have been grown with repressed lachrymatory factor synthase (LFS) activity, which causes these onions to produce increased amounts of di-1-propenyl thiosulfinate, an isomer of allicin.

A Narcissus mosaic viral vector system for protein expression and flavonoid production.

Background: With the explosive numbers of sequences generated by next generation sequencing, the demand for high throughput screening to understand gene function has grown. Plant viral vectors have been widely used as tools in down-regulating plant gene expression. However, plant viral vectors can also express proteins in a very efficient manner and, therefore, can also serve as a valuable tool for characterizing proteins and their functions in metabolic pathways in planta.

Fast phenotyping of LFS-silenced (tearless) onions by desorption electrospray ionization mass spectrometry (DESI-MS).

Fast MS techniques have been applied to the analysis of sulfur volatiles in Allium species and varieties to distinguish phenotypes. Headspace sampling by proton transfer reaction (PTR) MS and surface sampling by desorption electrospray ionization (DESI) MS were used to distinguish lachrymatory factor synthase (LFS)-silenced (tearless; LFS-) onions from normal, LFS-active (tear-inducing; LFS+), onions. PTR-MS showed lower concentrations of the lachrymatory factor (LF, 3) and dipropyl disulfide 12 from tearless onions.

A mass spectrometric method for quantifying C3 and C6 phosphorylation of starch.

The glucosyl residues comprising starch can be phosphorylated at either the C3 or the C6 position of the molecule because of the activities of two distinct dikinase enzymes. After hydrolysis of the starch, the C6 phosphorylation is easy to measure using a routine enzyme assay for glucose 6-phosphate, but the C3 phosphorylation is more difficult to assay. A mass spectrometric (MS) method has been developed that, in a single run, can distinguish and quantify the glucose 3-phosphate and glucose 6-phosphate produced by hydrolysis of starch and can also measure the glucose content to give an accurate estimate of the starting material.

Biofortification of tomato (Solanum lycopersicum) fruit with the anticancer compound methylselenocysteine using a selenocysteine methyltransferase from a selenium hyperaccumulator.

Methylselenocysteine (MeSeCys) is an amino acid derivative that possesses potent anticancer activity in animals. Plants that can tolerate growth on soils with high Se content, known as Se hyperaccumulators, do so by converting inorganic Se to MeSeCys by the enzyme selenocysteine methyltransferase (SMT). A cDNA encoding the SMT from a Se hyperaccumulator was overexpressed in tomato (Solanum lycopersicum).

Amyloid fibril formation from crude protein mixtures.

Amyloid fibrils have potential as bionanomaterials. A bottleneck in their commercial use is the cost of the highly purified protein typically needed as a starting material. Thus, an understanding of the role of heterogeneity in the mixtures from which amyloid fibrils are formed may inform production of these structures from readily available impure starting materials.

Metabolomic analysis identifies inflammatory and noninflammatory metabolic effects of genetic modification in a mouse model of Crohn's disease.

Interleukin-10 is an immunosuppressive cytokine involved in the regulation of gastrointestinal mucosal immunity toward intestinal microbiota. Interleukin-10-deficient (IL10(-/-)) mice develop Crohn's disease-like colitis unless raised in germ-free conditions. Previous gas chromatography-mass spectrometry (GC-MS) metabolomic analysis revealed urinary metabolite differences between IL10(-/-) and wildtype C57BL/6 mice.

Sesquiterpene lactones in Arnica montana: helenalin and dihydrohelenalin chemotypes in Spain.

An analytical RPLC method for sesquiterpene lactones in Arnica montana has been extended to include quantitative analyses of dihydrohelenalin esters. LC-ESI-MS-MS distinguished the isomeric helenalin and dihydrohelenalin esters. The dihydrohelenalin esters have lower response factors for UV detection than do helenalin esters, which must be taken into account for quantitative analyses.

Accumulation of an organic anticancer selenium compound in a transgenic Solanaceous species shows wider applicability of the selenocysteine methyltransferase transgene from selenium hyperaccumulators.

Tolerance to high selenium (Se) soils in Se-hyperaccumulating plant species is correlated with the ability to biosynthesise methylselenocysteine (MeSeCys), due to the activity of selenocysteine methyltransferase (SMT). In mammals, inclusion of MeSeCys in the diet reduces the incidence of certain cancers, so increasing the range of crop plants that can produce this compound is an attractive biotechnology target. However, in the non-Se accumulator Arabidopsis, overexpression of SMT does not result in biosynthesis of MeSeCys from selenate because the rate at which selenate is reduced to selenite by ATP sulfurylase (ATPS) is low.

Betalains in red and yellow varieties of the Andean tuber crop ulluco (Ullucus tuberosus).

The betalain pigments in ulluco (Ullucus tuberosus), a tuberous crop native to the Andes, have been investigated for the first time using LC-DAD-ESI-MS-MS(2) analyses. Five red, yellow, and red-spotted accessions introduced into New Zealand as a new food crop plus two red tetraploid lines were investigated. Thirty-two different betalains were identified.

The effect of oxidation or alkylation on the separation of wool keratin proteins by two-dimensional gel electrophoresis.

Comparative two-dimensional electrophoretic (2-DE) studies were performed over a time-course to examine the effect of oxidation or alkylation on the separation of wool keratin proteins. The effect of oxidation was followed by treating scoured wool fibres with increasing levels of hydrogen peroxide, ranging from 0-12 g/L, using conditions mimicking the industrial wool bleaching process. Peroxide treatment was found to have only a minor effect on the 2-DE separation of the intermediate filament protein (IFP) class.