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Zeaxanthin, along with its isomer lutein, are the major carotenoids contributing to the characteristic colour of yellow sweet-corn. From a human health perspective, these two carotenoids are also specifically accumulated in the human macula, and are thought to protect the photoreceptor cells of the eye from blue light oxidative damage and to improve visual acuity. As humans cannot synthesise these compounds, they must be accumulated from dietary components containing zeaxanthin and lutein. In comparison to most dietary sources, yellow sweet-corn (Zea mays var. rugosa) is a particularly good source of zeaxanthin, although the concentration of zeaxanthin is still fairly low in comparison to what is considered a supplementary dose to improve macular pigment concentration (2mg/person/day). In our present project, we have increased zeaxanthin concentration in sweet-corn kernels from 0.2 to 0.3mg/100g FW to greater than 2.0mg/100g FW at sweet-corn eating-stage, substantially reducing the amount of corn required to provide the same dosage of zeaxanthin. This was achieved by altering the carotenoid synthesis pathway to more than double total carotenoid synthesis and to redirect carotenoid synthesis towards the β-arm of the pathway where zeaxanthin is synthesised. This resulted in a proportional increase of zeaxanthin from 22% to 70% of the total carotenoid present. As kernels increase in physiological maturity, carotenoid concentration also significantly increases, mainly due to increased synthesis but also due to a decline in moisture content of the kernels. When fully mature, dried kernels can reach zeaxanthin and β-carotene concentrations of 8.7 mg/100g and 2.6 mg/100g, respectively. Although kernels continue to increase in zeaxanthin when harvested past their normal harvest maturity stage, the texture of these 'over-mature' kernels is tough, making them less appealing for fresh consumption. Increase in zeaxanthin concentration and other orange carotenoids such as β-carotene also results in a decline in kernel hue angle of fresh sweet-corn from approximately 90° (yellow) to as low as 75° (orange-yellow). This enables high-zeaxanthin sweet-corn to be visually-distinguishable from standard yellow sweet-corn, which is predominantly pigmented by lutein., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Previous reviews of plum phytochemical content and health benefits have concentrated on the European plum, Prunus domestica L. However, the potential bioactivity of red- and dark red-fleshed Japanese plums, Prunus salicina Lindl., so-called blood plums, appears to warrant a significant increase in exposure, as indicated in a recent review of the whole Prunus genus. Furthermore, Japanese plums are the predominant plum produced on an international basis. In this review the nutrient and phytochemical content, breeding, horticultural practice, postharvest treatment and processing as well as bioactivity (emphasising in vivo studies) of Japanese plum are considered, with a focus on the anthocyanin content that distinguishes the blood plums., (© 2014 State of Queensland Journal of the Science of Food and Agriculture © 2014 Society of Chemical Industry.)

Carotenoids are responsible for the yellow color of sweet corn (Zea mays var. saccharata), but are also potentially the source of flavor compounds from the cleavage of carotenoid molecules. The carotenoid-derived volatile, β-ionone, was identified in both standard yellow sweet corn ('Hybrix5') and a zeaxanthin-enhanced experimental variety ('HZ') designed for sufferers of macular degeneration. As β-ionone is highly perceivable at extremely low concentration by humans, it was important to confirm if alterations in carotenoid profile may also affect flavor volatiles. The concentration of β-ionone was most strongly correlated (R(2) > 0.94) with the β-arm carotenoids, β-carotene, β-cryptoxanthin, and zeaxanthin, and to a lesser degree (R(2) = 0.90) with the α-arm carotenoid, zeinoxanthin. No correlation existed with either lutein (R(2) = 0.06) or antheraxanthin (R(2) = 0.10). Delaying harvest of cobs resulted in a significant increase of both carotenoid and β-ionone concentrations, producing a 6-fold increase of β-ionone in 'HZ' and a 2-fold increase in 'Hybrix5', reaching a maximum of 62 μg/kg FW and 24 μg/kg FW, respectively.

Background: Diets high in fruit and vegetables are known to have significant health benefits. This is in part due to the presence of phytochemicals, which possess potential protective health benefits. This study focuses on the ability of strawberries to be bred for higher anthocyanin content. This is a major contributor to the characteristic colour and nutritional value of ripe strawberries, together with phenolic acids, ascorbic acid and total antioxidant capacity., Results: Anthocyanins in five commercial strawberry cultivars and three breeding lines were assessed. This led to the discovery of one breeding line (BL 2006-221) as an exceptional source of anthocyanins (~1 g kg(-1) fresh weight), with approximately double the levels of current commercial cultivars. Temperature was shown to influence anthocyanin extraction, with 40 °C being the best extraction temperature using the accelerated solvent extraction (ASE) method. Hue angle and anthocyanin concentration showed a good correlation (r(2) = 0.69)., Conclusion: The new breeding line BL 2006-221 has the potential to be used in the development of phytochemically rich strawberry cultivars. Using hue angle as a screening tool for total anthocyanin concentration and extraction of anthocyanins from strawberries by ASE at 40 °C would support such cultivar development., (© 2012 Commonwealth of Australia.)

This work sought to define how pancreatitis affected antibiotic distribution in a perfused rat pancreas model. The distribution kinetics of four antibiotics were examined in control animals and animals with pancreatitis. Meropenem and piperacillin distributed into the extracellular space, and their distribution kinetics were unaffected by pancreatitis. In contrast, in pancreatic cells from animals with pancreatitis, ciprofloxacin showed a reduced uptake and clindamycin showed a reduced distribution.

Background: New varieties of fruits and vegetables, with higher carotenoid levels, are being developed to improve the potential health benefits to consumers. To assist the development of a new variety of high zeaxanthin sweetcorn, an analytical screening method was developed, including chromameter measurement of hue angle and optimized extraction for HPLC, and applied to 385 lines of a breeding population and six commercial varieties., Results: Saponification had no effect on carotenoid extraction. In the breeding population, carotenoid levels had a wide range with the highest levels of zeaxanthin being 11.9 mg kg(-1) fresh weight, which was at least six times greater than the tested commercial varieties. The regression of hue angle versus zeaxanthin was described by the equation, hue angle = 76.16 + 4.50 x exp(-0.24 x zeaxanthin) + 11.73 x exp(-0.24 x zeaxanthin), r(2) of 0.59. The top 6% of lines, with regards to zeaxanthin (zeaxanthin + beta-cryptoxanthin + beta-carotene) and total carotenoids, all had hue angles

This study examined the physicochemical-pharmacokinetic relationships for the sulphonylureas in the perfused rat pancreas and liver. Multiple indicator dilution studies were conducted with bolus injections of tolbutamide, chlorpropamide, gliclazide, glipizide, glibenclamide and glimepiride, and a reference marker albumin, in the perfused pancreas and liver. Individual solute pharmacokinetics were analysed using nonparametric moment analysis and nonlinear regression assuming a physiologically based pharmacokinetic model. All solutes had similar shaped outflow concentration-time profiles in both the pancreas and liver, but varied in extraction. Negligible drug extraction was evident in the pancreas. Hepatic extraction ranged from 0.03 (tolbutamide) to 0.52 (glibenclamide) and could be related to solute lipophilicity and perfusate protein binding. The sulphonylurea mean transit times in both the pancreas and liver varied four- and ninefold respectively and were related to the lipophilicity and perfusate protein binding of the drug. The permeability surface area product of sulphonylureas from the perfusate into the organs were greater in the liver and were mainly determined by lipophilicity (pancreas, r2 = 0.89; liver, r2 = 0.80). The distribution of the sulphonylureas in both the perfused pancreas and perfused liver was dependent on their lipophilicity and perfusate protein binding., (Copyright 2009 Wiley-Liss, Inc.)

Purpose: To set up and validate a viable perfused rat pancreas model suitable for pharmacokinetic studies., Materials and Methods: We setup and conducted multiple indicator dilution studies in the single pass perfused rat pancreas. The distribution of the reference markers [99mTc]-red blood cells (RBC), [14C]-sucrose, and [3H]-water, and tolbutamide were analysed using both non-parametric and parametric methods., Results: The perfusion preparation was observed to be viable by oxygen consumption, outflow perfusate pH, lactate release and insulin release in response to glucose. Parametric analysis of the outflow profiles suggested that the transport of water and tolbutamide from the vascular space was permeability limited. Parametric and nonparametric estimates of Vd for RBC and sucrose were similar and were 0.14+/-0.01, 0.15 0.005 and 0.35+/-0.01 ml/g. The parametric estimate for water, 1.04+/-0.05 ml/g was greater than the nonparametric estimate, 0.89+/-0.02 ml/g. The multiple indicator dilution method Vd of tolbutamide of 0.75+0.08 ml/g was similar to the reported value of 0.73+/-0.04 ml/g estimated by tissue partitioning studies., Conclusions: A viable single pass pancreas perfusion model was established and applied to define distribution spaces of reference markers and the distribution kinetics of tolbutamide.

Hyperprolactinaemia during lactation is a consequence of the sucking stimulus and in part due to reduced prolactin (PRL) negative feedback. To date, the mechanisms involved in this diminished sensitivity to PRL feedback are unknown but may involve changes in PRL signal transduction within tuberoinfundibular dopaminergic (TIDA) neurons. Therefore, we investigated signal transducers and activators of transcription (STAT) 5 signaling in the TIDA neurons of lactating rats. Dual-label confocal immunofluorescence studies were used to determine the intracellular distribution of STAT5 within TIDA neurons in the dorsomedial arcuate nucleus. In lactating rats with pups removed for 16 h, injection of ovine PRL significantly (P < 0.05) increased the STAT5 nuclear/cytoplasmic ratio compared with vehicle-treated mothers. In contrast, ovine PRL injection did not increase the STAT5 nuclear/cytoplasmic ratio in lactating mothers with pups, demonstrating that PRL signal transduction through STAT5 is reduced in TIDA neurons in the presence of pups. To investigate possible mechanisms involved in reduced PRL signaling, we examined the expression of suppressors of cytokine signaling (SOCS) proteins. Northern analysis on whole hypothalamus showed that CIS (cytokine-inducible SH2 domain-containing protein), but not SOCS1 or SOCS3, mRNA expression was significantly (P < 0.01) up-regulated in suckled lactating rats. Semiquantitative RT-PCR on arcuate nucleus micropunches also showed up-regulation of CIS transcripts. Immunofluorescence studies demonstrated that CIS is expressed in all TIDA neurons in the dorsomedial arcuate nucleus, and the intensity of CIS staining in these neurons is significantly (P < 0.05) increased in lactating rats with sucking pups. Together, these results support the hypothesis that loss of sensitivity to PRL-negative feedback during lactation is a result of increased CIS expression in TIDA neurons.

To assess the availability of Ca2+ in the lumen of the thylakoid membrane that is required to support the assembly of the oxygen-evolving complex of photosystem II, we have investigated the mechanism of 45Ca2+ transport into the lumen of pea (Pisum sativum) thylakoid membranes using silicone-oil centrifugation. Trans-thylakoid Ca2+ transport is dependent on light or, in the dark, on exogenously added ATP. Both light and ATP hydrolysis are coupled to Ca2+ transport through the formation of a transthylakoid pH gradient. The H+-transporting ionophores nigericin/K+ and carbonyl cyanide 3-chlorophenylhydrazone inhibit the transport of Ca2+. Thylakoid membranes are capable of accumulating up to 30 nmol Ca2+ mg-1 chlorophyll from external concentrations of 15 μM over the course of a 15-min reaction. These results are consistent with the presence of an active Ca2+/H+ antiport in the thylakoid membrane. Ca2+ transport across the thylakoid membrane has significant implications for chloroplast and plant Ca2+ homeostasis. We propose a model of chloroplast Ca2+ regulation whereby the activity of the Ca2+/H+ antiporter facilitates the light-dependent uptake of Ca2+ by chloroplasts and reduces stromal Ca2+ levels.