Anthocyanins, the naturally occurring pigments responsible for most red to blue colours of flowers, fruits and vegetables, have also attracted interest because of their potential health effects. With the aim of contributing to major insights into their structure–activity relationship (SAR), we have evaluated the radical scavenging and biological activities of selected purified anthocyanin samples (PASs) from various anthocyanin-rich plant materials: two fruits (mahaleb cherry and blackcurrant) and two vegetables (black carrot and “Sun Black” tomato), differing in anthocyanin content (ranging from 4.9 to 38.5 mg/g DW) and molecular structure of the predominant anthocyanins. PASs from the abovementioned plant materials have been evaluated for their antioxidant capacity using Trolox Equivalent Antioxidant Capacity (TEAC) and Oxygen Radical Absorbance Capacity (ORAC) assays. In human endothelial cells, we analysed the anti-inflammatory activity of different PASs by measuring their effects on the expression of endothelial adhesion molecules VCAM-1 and ICAM-1. We demonstrated that all the different PASs showed biological activity. They exhibited antioxidant capacity of different magnitude, higher for samples containing non-acylated anthocyanins (typical for fruits) compared to samples containing more complex anthocyanins acylated with cinnamic acid derivatives (typical for vegetables), even though this order was slightly reversed when ORAC assay values were expressed on a molar basis. Concordantly, PASs containing non-acylated anthocyanins reduced the expression of endothelial inflammatory antigens more than samples with aromatic acylated anthocyanins, suggesting the potential beneficial effect of structurally diverse anthocyanins in cardiovascular protection.

Anthocyanins are key pigments of plants, providing color to flowers, fruit, and foliage and helping to counter the harmful effects of environmental stresses. It is generally assumed that anthocyanin biosynthesis arose during the evolutionary transition of plants from aquatic to land environments. Liverworts, which may be the closest living relatives to the first land plants, have been reported to produce red cell wall-bound riccionidin pigments in response to stresses such as UV-B light, drought, and nutrient deprivation, and these have been proposed to correspond to the first anthocyanidins present in early land plant ancestors. Taking advantage of the liverwort model species Marchantia polymorpha, we show that the red pigments of Marchantia are formed by a phenylpropanoid biosynthetic branch distinct from that leading to anthocyanins. They constitute a previously unreported flavonoid class, for which we propose the name “auronidin,” with similar colors as anthocyanin but different chemistry, including strong fluorescence. Auronidins might contribute to the remarkable ability of liverworts to survive in extreme environments on land, and their discovery calls into question the possible pigment status of the first land plants.

Tomato ( Solanum lycopersicum L.) is one of the most cultivated vegetable in the world and it represents a large source of bioactive compounds, including carotenoids and polyphenols (phenolic acids and flavonoids). However, the concentration of flavonoids in tomato is considered sub-optimal, particularly because anthocyanins are not generally present. Therefore, this crop has been the object of an intense metabolic engineering in order to obtain anthocyanin-enriched tomatoes by using either breeding or transgenic strategies. Some wild tomato species, such as S. chilense and S. cheesmaniae , biosynthesize anthocyanins in the fruit sub-epidermal tissue, and some alleles from those genotypes have been introgressed into a new developed purple tomato line, called “Sun Black” (SB). It is a tomato line with a purple skin color, both in green and in red fruit stages, due to the biosynthesis of anthocyanins in the peel, and a normal red color pulp, with a taste just like a traditional tomato. SB is the result of a breeding programme and it is not a genetically modified (GM) product. We report the chemical characterization and structure elucidation of the attractive anthocyanins found in the peel of SB tomato, as well as other bioactive compounds (carotenoids, polyphenols, vitamin C) of the whole fruit. Using one- and two-dimensional NMR experiments, the two main anthocyanins were identified to be petunidin 3- O -[6″- O -(4 ‴ - O - E - p- coumaroyl-α-rhamnopyranosyl) -β-glucopyranoside]-5- O -β-glucopyranoside (petanin) and malvidin 3- O -[6″- O -(4 ‴ - O - E - p- coumaroyl-α-rhamnopyranosyl)-β-glucopyranoside]-5- O -β-glucopyranoside (negretein). The total anthocyanins in the whole ripe fruit was 1.2 mg/g dry weight (DW); 7.1 mg/100 g fresh weight (FW). Chlorogenic acid (the most abundant phenolic acid) was 0.6 mg/g DW; 3.7 mg/100 g FW. The main flavonol, rutin was 0.8 mg/g DW; 5 mg/100 g FW. The total carotenoid content was 211.3 μg/g DW; 1,268 μg/100 g FW. The total phenolic content was 8.6 mg/g DW; 52.2 mg/100 g FW. The vitamin C content was 37.3 mg/100 g FW. The antioxidant activities as measured by the TEAC and ORAC assays were 31.6 and 140.3 μmol TE/g DW, respectively (193 and 855.8 μmol TE/100 g FW, respectively). The results show the unique features of this new tomato genotype with nutraceutical properties.

Anthocyanins with various functions in nature are one of the most important sources of colours in plants. They are based on anthocyanidins or 3-deoxyanthocyanidins having in common a C15-skeleton and are unique in terms of how each anthocyanidin is involved in a network of equilibria between different forms exhibiting their own properties including colour. Sphagnorubin C (1) isolated from the cell wall of peat moss (Sphagnum sp.) was in fairly acidic and neutral dimethyl sulfoxide characterized by nuclear magnetic resonance (NMR) and ultraviolet–visible (UV–vis) absorption techniques. At equilibrium, the network of 1 behaved as a two–component colour system involving the reddish flavylium cationic and the yellow trans–chalcone forms. The additional D- and E-rings connected to the common C15-skeleton extend the π-conjugation within the molecule and provide both bathochromic shifts in the absorption spectra of the various forms as well as a low isomerization barrier between the cis- and trans-chalcone forms. The hemiketal and cis-chalcone forms were thus not observed experimentally by NMR due to their short lives. The stable, reversible network of 1 with good colour contrast between its two components has previously not been reported for other natural anthocyanins and might thus have potential in future photochromic systems. This is the first full structural characterization of any naturally occurring anthocyanin chalcone form.

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Anthocyanins, the naturally occurring pigments responsible for most red to blue colours

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In this age of multi-zone and multilateral wells, existing technologies are always challenged to achieve desired results. In the case of Statoil Skinfaks/Rimfaks (SRI) wells, capabilities of intelligent completion systems were stretched to the limit. Some of the challenges included depth, system optimization, feedback monitoring, subsea logic, placement of downhole hydraulic logic switches, hydraulic timing, cross flow design due to limited control lines, development of an auxiliary logic switch, etc. Operational requirements also pushed downhole tools like the flow control valves and logic switches in a novel and previously untried configuration. System operation logic mandated the design of a very complex hydraulic circuit. Cross flow design with limited control lines proved to be a significant challenge. Each of the wells had three zones to be controlled. The existing subsea trees allowed only three hydraulic control lines. Three balanced piston flow control valves normally require at least four control lines to be operated. A new system was to be developed to be able to control all three balanced piston valves with only three hydraulic control lines. This paper will present how a combination of analytical modeling, simulation and laboratory testing was used to overcome these and other design challenges during the system development phase. This novel methodology will aid the optimization and reduction in design cycle time of future intelligent completion systems. Four wells in the Statoil Skinfaks/Rimfaks Improved Oil Recovery Project were completed with intelligent systems in 2007. Thorough planning and execution yielded higher operational efficiency which resulted in job completion ahead of schedule. The installation phase will be discussed in the paper with special emphasis on pre-job planning, operational procedures, post-job results and lessons learned. Introduction The Skinfaks/Rimfaks Improved Oil Recovery wells are located in the Gullfaks oil and gas field. Four wells in the field were completed with intelligent systems. Each well had three zones and was approximately 4,900 meters deep. Systems designed to operate each well included adjustable flow control choking valves, hydraulic logic switches to address these valves and thousands of meters of control line for communication between the different components. Maintaining system reliability was important while designing the complex hydraulic circuit to operate the system. In order to overcome design challenges, a combination of analysis and laboratory testing was performed. Successful installation of any completion system requires systematic planning and close coordination between equipment suppliers, especially since they are located in different parts of the world. Periodic meetings facilitated proper communication between the operator and service companies. The objective was to minimize non-productive time during installation. System Design Completion design objectives for the wells included the installation of three surface controlled adjustable choking valves. Normally three hydraulically operated valves would require the installation of four control lines extending from the Christmas tree to the valves. The conventional control scheme dedicates one control line per valve to open each valve and a single shared control line used to close all of the valves. However, the available subsea tree and hanger provided only three available hydraulic communication paths. To accommodate the situation of limited number of penetrations, an alternate control method is available using a single control line to the valve plus an auxiliary switching valve known as the Single Line Switch (SLS).