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Sunflecks are transient patches of direct radiation that provide a substantial proportion of the daily irradiance to leaves in the lower canopy. In this position, faster photosynthetic induction would allow for higher sunfleck-use efficiency, as is commonly reported in the literature. Yet, when sunflecks are too few and far between, it may be more beneficial for shade leaves to prioritize efficient photosynthesis under shade. We investigated the temporal dynamics of photosynthetic induction, recovery under shade, and stomatal movement during a sunfleck, in sun and shade leaves of Fagus sylvatica from three provenances of contrasting origin. We found that shade leaves complete full induction in a shorter time than sun leaves, but that sun leaves respond faster than shade leaves due to their much larger amplitude of induction. The core-range provenance achieved faster stomatal opening in shade leaves, which may allow for better sunfleck-use efficiency in denser canopies and lower canopy positions. Our findings represent a paradigm shift for future research into light fluctuations in canopies, drawing attention to the ubiquitous importance of sunflecks for photosynthesis, not only in lower-canopy leaves where shade is prevalent, but particularly in the upper canopy where longer sunflecks are more common due to canopy openness.

The yield of high-value products, such as pigments that could be extracted from microalgae, is affected by various nutritional and physical factors. Consequently, there is a need for fast visualization techniques that investigate the responses of individual microalgal cells to changing environmental conditions without introducing perturbations. Here, we apply CARS microscopy to map the distribution of pigments in the diatoms Ditylum brightwellii and Stephanopyxis turris and report their relative change in response to varying light cycles using a marker-based watershed analysis of the acquired images. Simultaneously, the underlying specific pigment composition alterations are revealed using Raman microspectroscopy at 785 nm excitation. In regards to assessing the chemical content of microalgae, these methods present themselves as viable alternatives to the standard techniques currently in use because of their non-disruptive nature and the wealth of complementary information that could be obtained from them.

Summary Growth and pigment composition of both the skeleton-bearing and naked forms and toxicology of the naked form of Dictyocha octonaria were studied here using clonal cultures derived from a single cell from Wellington Harbour. In this study both the naked and skeleton-bearing forms showed optimum growth between 14 and 18°C. Maximum growth rates of the naked and skeleton-bearing forms were 1.46 and 0.99 division day−1, respectively. Growth rates of the naked form at temperatures 22°C. Cells of the naked form died at 24°C while those of the skeleton-bearing form at 26°C. In this study the naked and skeleton-bearing forms cultured in identical growth conditions contained almost the same pigments, except zeaxanthin, which made up about 3.2% of the total carotenoid in the skeleton-bearing form and virtually none in the naked form. Toxicological tests conducted on rotifers indicated that the naked form was not harmful to the test organisms.

Summary Elderberry concentrate is widely used for food colouring. Its production includes several processing steps, which influence pigment composition, thus affecting the quality of final product. In this study, qualitative and quantitative changes in anthocyanin components were followed during the production of elderberry juice concentrate using Haschberg and Samocco varieties. Juice concentration resulted in more than five-fold concentration increase in anthocyanins; however, clarification, filtration and evaporation steps caused slight but continuous decrease in anthocyanins relative to the dry matter of the product. Pectolytic enzymatic treatment was found to be one of the most critical processing steps that affects anthocyanin yield during production, and this effect on yield can be variety-dependent. Additionally, two condensed dimeric anthocyanin species generated after heat treatment are reported for the first time to be present in elderberry juice concentrate. Our results suggest that cyanidin-based anthocyanin conjugates with more complex saccharide moieties are more robust during production.

Pigmentation secondary to minocycline ingestion is an uncommon adverse event affecting 3.7-14.8% of treated individuals for which few effective therapies are available. Three patterns of minocycline pigmentation have a characteristic clinical and histological appearance. The pigment composition in each variety is different and occurs at varying skin depths. Accordingly, a tailored approach according to the type of minocycline pigmentation is crucial for treatment success. The purpose of this intervention was to evaluate the efficacy of non-ablative fractional photothermolysis in combination with the Q-switched alexandrite laser for the treatment of type I minocycline pigmentation on the face. A patient with type I minocycline pigmentation was treated with non-ablative 1550-nm fractional photothermolysis followed immediately by 755-nm Q-switched alexandrite laser and then observed clinically to determine the outcome of this modality. The patient was seen in clinic 1 month later following her single treatment session and 100% clearance of all blue facial pigment was observed. Non-ablative fractional photothermolysis in combination with the 755-nm Q-switched alexandrite laser should be considered for treatment of type I minocycline pigmentation.

Strengths of numerical relationships between phytoplankton abundance estimates made by microscopy and CHEMTAX have often been tested using regression analysis. To specifically test agreement, where data points lie along a line of equality, the Bland and Altman technique is commonly used in the medical literature and applied here to phytoplankton analysis for the first time (simultaneously with regression). Our analyses are based on a sample set collected off Coffs Harbour (∼ 30°S), Eastern Australia. While comparing abundance estimates of different phytoplankton pigment-types derived from microscopy and CHEMTAX we specifically aim at: (1) determining the usefulness of the Bland and Altman technique in comparing phytoplankton abundance estimates made by both quantification techniques, and (2) identifying the lowest taxonomic level (i.e., interclass or intraclass level) at which phytoplankton abundance estimates agree. Our results suggest that Bland and Altman analysis is highly suited to compare phytoplankton abundance estimates made by microscopy and CHEMTAX. It delivered a quantifiable difference of chlorophyll a concentrations between abundance estimates, which may benefit the future calibration of phytoplankton quantification techniques. Both Bland and Altman and regression analyses were suited to resolve imbalances between phytoplankton abundance estimates made by microscopy and CHEMTAX. Best agreement was found within dinoflagellates (class-level), poor agreement within three diatom pigment-types (intraclass level). We attributed the poor agreement within diatom abundance estimates to classification errors of microscopically determined taxa into pigment-types. Intraspecific pigment composition seems more variable than generally assumed, calling for studies resolving this variation to further conform abundance estimates made by microscopy and CHEMTAX.

The use of the photochemical reflectance index (PRI) as a promising proxy of light use efficiency (LUE) has been extensively studied, and some issues have been identified, notably the sensitivity of PRI to leaf pigment composition and the variability in PRI response to LUE because of stress. In this study, we introduce a method that enables us to track the short-term PRI response to LUE changes because of photosynthetically active radiation (PAR) changes. The analysis of these short-term relationships between PRI and LUE throughout the growing season in two species (Quercus robur L. and Fagus sylvatica L.) under two different soil water statuses showed a clear change in PRI response to LUE, which is related to leaf pigment content.The use of an estimated or approximated PRI0, defined as the PRI of perfectly dark-adapted leaves, allowed us to separate the PRI variability due to leaf pigment content changes and the physiologically related PRI variability over both daily (PARrelated) and seasonal (soil water content-related) scales.The corrected PRI obtained by subtracting PRI0 from the PRI measurements showed a good correlation with the LUE over both of the species, soil water statuses and over the entire growing season.

The effect of the proportion of ‘Hass’ avocado skin tissue present during aqueous cold pressed avocado oil extraction on the pigment concentration and oil quality was determined. Increasing amounts of skin (i.e., from 0 to 100% of available skin) were included with the flesh before grinding and malaxing in a laboratory-scale cold pressed extraction process. The recovered oils were analyzed for oil quality and color. The pigment concentrations in the oil were determined by high performance liquid chromatography (HPLC). With increasing amounts of skin addition, there was an increase in the green color, as indicated by hue angle, of the avocado oils. There were also increased concentrations of carotenoids and chlorophylls in the oil as the proportion of skin during malaxing was increased. The lutein concentration in the oils increased from 1.13 to 3.21 μg g−1 as the amount of skin added to the malaxer increased from 0 to 100% skin, and the total chlorophyll concentration in the same oils increased from 7.3 to 27.5 μg g−1. The green color of cold pressed avocado oil and the pigment concentrations can be increased by adding more skin to the malaxer during oil extraction.

The results of the analyses of elemental composition of red and black pigments of Levantine rock art from La Saltadora rock shelters (Valltorta gorge, Castellon, Spain) are presented in this paper. Nondestructive analyses were carried out using a portable energy dispersive X-ray fluorescence (EDXRF) spectrometer developed for in situ analysis. The results revealed the strong presence of calcium in all the analyzed locations due to the contribution of the underlying calcareous bedrock and the overlying crust. Iron is the main element detected in red pigments and manganese in black pigments. Iron and calcium ratios have been found indicative of the degree of preservation of the pictorial layer. Trace elements detected in the pigment composition confirm the use of different raw materials. Therefore, this work illustrates the potential of the portable EDXRF spectrometers for in situ analysis of rock art paintings. Copyright © 2010 John Wiley & Sons, Ltd.

Summary Some basic aspects of the determination of the relative proportions of myoglobin pigments in meat by reflectance spectrophotometry are briefly reviewed. The potential of the Unicam SP 890 diffuse reflectance accessory for the quantitative determination of myoglobin forms in beef is assessed. The construction of the Unicam apparatus differs from most other reflectance units in that it has no integration sphere. The K/S values obtained with the Unicam apparatus and the requirements to be met by the samples correlate well with those for other spectrophotometric apparatus, except that the thickness of meat samples does not seem to affect the measured reflectance. A simple and rapid method is described for the determination by reflectance spectrophotometry of the proportion of oxymyoglobin and ferric myoglobin in meat surfaces. If only negligible amounts of reduced myoglobin are present in the sample, then the absorbance at 580 nm minus the absorbance at 630 nm is linearly related to the percentage of oxymyoglobin, or ferric myoglobin. The theoretical basis for this linear relationship is outlined. A drawback of the method is that the difference in absorbance (A580 - A632) is dependent on the myoglobin concentration in the meat sample. Nevertheless, the method is very convenient for comparing the pigment composition of meat samples with similar myoglobin contents and for following the course of pigment changes in a single meat sample.

Summary The quantitative distribution of chlorophylls and carotenoids in five capsicum cultivars at four stages of maturation and ripening has been established using chromatographic, spectroscopic and chemical methods. From immature, mature, half-ripened and fully-ripened capsicum fruits, up to twelve, twelve, twenty-nine and twenty-six individual pigments respectively were isolated and most identified. The pigment composition results were consistent with a proposed pathway of synthesis of the red keto-carotenoids, capsanthin and capsorubin. Significant differences were found in pigment concentrations among the cultivars at all stages of maturation and ripening, even though the cultivars showed the same visual colour. Lycopene and chlorophyll pigments other than chlorophylls a and b were not found in any cultivar at any stage of maturation or ripening.

Summary Reflectance measurements and subjective colour evaluations of retail-packed beef were recorded and compared. Subjective colour evaluation, which was found to be closely linked to the visual assessment of the overall quality of the meat, is largely determined by the percentage of oxymyoglobin (red) relative to ferric myoglobin (brown). The reflectance colour value, which is the difference in reflectances (expressed in absorbance units) at 580 and 630 nm, is linearly related to the percentage of oxymyoglobin and to the subjective colour score. The correlation between objective and subjective colour evaluation is statistically highly significant (correlation coefficient = 0.94). Reflectance spectrophotometry is thus shown to be a convenient and reliable method for objective colour measurement and for the determination of the pigment composition in the surface zone of intact beef samples.

Four clonal isolates of Nostoc linckia isolated from different localities were compared with respect to growth, nitrogen content (cellular and extracellular), and pigment composition. A considerable range of variation was observed among these isolates. This indicates the existence of genetically distinct clonal populations of the alga in natural habitats.

Calcifying and a noncalcifying strains of Emiliania huxleyi were cultured in nutrient replete turbidostats under a photon flux density (PFD) gradient from 50 to 600 μmol E · m -2 · s -1 . For both strains, growth was PFD-saturated at 300 μmol E · m -2 · s -1 . The strains, although with clearly different physiological properties due to the presence or absence of calcification, showed the same trends and magnitude of change in their pigment compliment as a function of PFD. Light-controlled pigment composition and the trends of change in pigment composition were identical in both strains. Fucoxanthin (Fuco) was the major carotenoid in the calcifying strain, while in the noncalcifying strain this role was assumed by 19' hexanoyloxyfucoxanthin (19 Hex). The photoprotective pigments and 19 Hex, normalized to chl a, increased with increasing light, while chl a content per cell and chl c's and Fuco, normalized to chl a, decreased with increasing PFD. The sum of all carotenoids normalized to chl a was remarkably similar in all PFDs used. Collectively, our results suggest that 19 Hex was synthesized from Fuco with light as a modulating factor and that the total amount of carotenoids is strain-specific and synthesized/catabolized in tandem with chl a to a genetically predefined level independent of PFD.

Bird cherry (Prunus padus) anthocyanins were extracted with acidified methanol, fractionated by column chromatography on Toyopearl HW40(S) and purified in a C-18 Sep-Pak cartridge. The pigment composition was very simple, as there were only two compounds. The anthocyanins cyanidin-3-rutinoside (60%) and cyanidin-3-glucoside (40%) were determined using chromatographic and spectroscopic methods. © 2002 Society of Chemical Industry

The phenolic constituents of 95 black teas, from nine countries, were analysed by HPLC. The procedure resolved 38 coloured phenolic components which were classified as theaflavins (4), thearubigins (22) and flavonol glycosides (11). One of the thearubigin constituents was unresolved chromatographically, but nevertheless quantified as a hump. The relative levels of these substances for different regions and countries of origin were compared. Statistical analysis of the HPLC results with discriminant analysis or canonical variant analysis and ANOVA, highlighted the characteristic differences in phenolic substance levels which contributed most powerfully to the discrimination between origins. Discriminant analysis revealed a discrimination rule based on phenolic composition which achieved a country of origin classification success of 94%. This type of approach highlights which substances are most important in defining origin in terms of tasters' assessments.

The phenolic constituents of 95 black teas, representing nine countries, were analysed and assessed by HPLC. The procedure resolved 38 coloured phenolic components which were classified as theaflavins (4), thearubigins (23) and flavonol glycosides (11). The relative levels of these constituents were monitored by HPLC. One of the thearubigin constituents was unresolved chromatographically, but nevertheless quantified as a hump. The data set was statistically analysed using principal component analysis (PCA) and multiple regression. PCA indicated that three of the quality attributes, quality/flavour, brightness/briskness and quality with milk, were strongly correlated with each other. The fourth attribute, colour/strength, was found to be the most effective in discriminating between teas, particularly between high strength teas from Assam and Tanzania and low strength teas from Sri Lanka and Malawi. Multiple regression was used to investigate the relationship between tasters' scores and the chemical constituents. The model established gives an R 2 of 63% based on six components; five resolved thearubigins and the unresolved thearubigin hump. These results indicate the potential to develop objective chemical assessment procedures for determining the quality of teas and is the first report of the flavour impact of individual thearubigins constituents.

6 Pags.- 1 Tabl.- 6 Figs., A D1-D2-cyt b-559 complex containing 4 chlorophyll a, 1 β-carotene and 1 cytochrome b-559 per 2 pheophytin a has been isolated from spinach with 30% yield using a Q-Sepharose Fast-Flow anion-exchange column equilibrated with 0.1% Triton X-100, 10 mM MgSO4 and 50 mM Tris-HCl (pH 7.2). The preparation was then stabilized with 0.1% dodecyl-β-d-maltoside. This method gave a yield 10 times higher than that using a Fractogel TSK-DEAE 650(S) column equilibrated with 0.1% Triton X-100, 30 mM NaCl and 50 mM Tris-HCl (pH 7.2). The PS II RC complex was characterized using absorption and fluorescence spectroscopy at 277 and 77 K. A selective reversible bleaching under reducing conditions with maximum at 682 nm, associated with pheophytin a reduction, and light-induced absorption differences with a lifetime of 1.0 ms, ascribed to the triplet state of P680 were measured and indicated that the isolated Dl-D2-cyt b-559 complex is active in charge separation. The results are compared with the data obtained for a PS II RC preparation containing 6 chlorophyll a, 2 β-carotene and 1 cyt b-559 per 2 pheophytin a.

The juices from 39 strawberry genotypes were analysed for anthocyanin composition and colour characteristics. No single cultivar or breeding line possessed the innate pigment characteristics thought to confer greater colour stability on strawberry juices but the anthocyanin patterns were far more complex than hitherto reported in strawberries. Thirteen different peaks were observed during high-performance liquid chromatography of the juices and tentative identifications are proposed for two previously unidentified strawberry anthocyanins. The occurrence of pelargonidin 3-rutinoside was confirmed. Colour quality measurements derived from CIELAB L*a*b* values are reported for the fresh juices.

Color stabilities were compared using various color indices-free an-thocyanin content, color density, polymeric color, browning and Hunter color values. Comparisons included both strawberry syrup plain and fortified with anthocyanins and/or ascorbic acid levels equivalent to those of blackcurrant syrup. Anthocynin pigments of unfortified strawberry syrup were less stable than those of blackcurrant syrup. Color stability of strawberry syrup fortified with equal anthocyanin concentrations was similar to blackcurrant syrup. Hence, color stability was dependent upon total anthocyanin concentration rather than qualitative pigment composition. Addition of ascorbic acid decreased color stability of strawberry syrup. Strawberry anthocyanin pigment fortification had a protective effect on ascorbic acid.

A tentative method is developed to determine the assimilative surface and the total and active photosynthetic volume in caespitose algal communities. The estimation of these variables and the analysis of photosynthetic pigments allow the description of structural adaptive responses in relation to light reception in two morphotypes of Corallina elongata, i. e., those growing in sunny and shaded intertidal localities. A cross transplantation of both morphotypes demonstrates that one type rapidly converts to the other. This indicates an adaptivity of morphology and pigment composition. The results presented in this work as well as the comparison between intertidal and terrestrial communities suggest that both have a similar potential efficiency in harvesting the incident radiation, but that the degree of compactation of the photosynthetic apparatus (Leaf Area Index) is different.

The pigmentation of five strains of Oscillatoria bornetii and four strains of Oscillatoria agardhii/rubescens were surveyed in vivo by spectrophotometry. The O. bornetii strains are very homogeneous with regard to qualitative pigment composition, but strain differences with regard to relative pigment content are remarkable. The O. agardhii/rubescens complex is variable, especially with regard to phycoerythrin content. In vivo pigment techniques may be promising as an additional, simple tool in blue–green algal taxonomy.

Eine Optimierung der Entwasserungsgeschwindigkeit der Streichfarbe durch entsprechende Pigmentzusammensetzung und Kombination, Elektrolytgehalt, Stabilitatsverhalten, Binderart und -menge usw., ist die Grundvoraussetzung fur eine positive Beeinflussung der Strichmorphologie und mus auf die jeweiligen Gegebenheiten, wie Rohpapier, Auftragssystem, Maschinengeschwindigkeit usw., abgestimmt werden. Dabei ist in allen Fallen ein schneller Stock- oder Immobilisierungspunkt der Streichfarbe anzustreben, um ein Absacken der Streichfarbe in das Rohpapier bzw. Bindemittepenetration in das Rohpapier sowie Bindemittelmigrationen an die Strichoberflache zu verhindern. bzw. Bindemittelpenetration in das Rohpapier sowie Bindemittelmigrationen an die Strichoberflache zu verhindern. The optimization of the rate of dewatering of coating dyes with respect to pigment composition and combination, electrolyte content, stability, kind and amount of binding agent etc. is considered the basic requirement of an advantageous effect on the coating morphology and has to be adapted to the actual conditions, as raw paper coating system, machine speed etc. Rapid immobilization has to be achieved in order to avoid the penetration of the coating dye and the binding agent into the raw paper as well as the migration of the binding agent on the coating surface.

Treatment with 6-benzylaminopurine (6-BAP; 10−5 g/ml) accelerates the growth of detached cucumber cotyledons (Cucumis sativas L.), primarily through an increased water uptake by the tissues. A comparative study of pigment composition and ultrastructure in 6-BAP treated and untreated cotyledons shows that cytokinin, in the presence of light, accelerates the transformation of etioplasts into chloroplasts. 6-BAP also enhances the synthesis of membrane precursors as indicated by the formation of a dense prolamellar body and by the persistence of a pseudo-cristalline structure in 6-BAP treated material. Stimulation of biosynthetic activity by cytokinin leads simultaneously to an increase in the rate of the pigment synthesis and to an acceleration in the building of the lamellar system. Furthermore, chloroplasts of 6-BAP treated cotyledons show abnormal features such as a striking increase in the number of thylacoids per granum and a poor development of the intergranal system.

— Conditions were established which allow selective alteration of the pigment composition of Anacystis cells. Nitrate-starvation at 28°C and 39°C resulted in the preponderance of chlorophyll a (Chi a) and that of phycocyanin (PC). In the case of starvation at 39°C strong correlation was observed between the disappearance of Chi a absorption and the appearance of an absorption band at 750 nm (P750) as the starvation proceeded. During regeneration the starved cells lost their P750 content. We show that P750 is quantitatively accounted for in the form of Chi a aggregates.

Pigment composition and color of a dark red Burgundy-type wine, strawberry preserves and canned strawberries were followed with time at a storage temperature of 37.7° Celcius. From thin-layer transreflectance measurements at two pH values, the normal pH of the products, 3.4, and on acidification to < 1.0, the course of anthocyanin degradation and brown polymer formation was followed. Experimental results suggested that on processing and during storage, anthocyanin pigment becomes incorporated into the pH nonresponsive polymeric moiety, resulting in a retardation of pigment degradation and thus, an increase in color stability.

—Chlorella cells were cultured in darkness on glucose and examined for pigment composition, capacity to evolve oxygen, and capacity to photo-oxidize artificial electron donors to Photosystems II and I. Evidence was obtained which indicated that such cells lack oxygen-evolving centers and the Mn pool associated with such centers but possess fully active System II and I trapping centers. Brief illumination (t1/2˜ 2–3 min) of dark-grown cells resulted in incorporation of Mn into the O2-evolving centers and the capacity to evolve O2 (photo-activation). Kinetic data from flashing or continuous light showed that the photoactivation is a multi-quantum process involving several rate limitations and a photosensitive state of limited stability. Measurements of oxygen-yield oscillations indicated that throughout the photoactivation process each newly formed oxygen-yielding center was independent of its neighbors. It is concluded that photoactivation of the Mn-containing oxygen-yielding catalyst is a fundamental process in all photosynthetic oxygen-evolving tissue.

Durch Verwendung geeigneter Zusatzstoffe wird versucht, das Fliesverhalten der Anstrichstoffe so zu steuern, das thixotrope Systeme entstehen. Die Wirkungsweise dieser thixotropen Zusatzstoffe ist von einigen Faktoren (Olgehalt, Pigment-Zusammensetzung, Fullstoffteilchen usw.) der Lack-Rezeptur abhangig. Influence of Thixotropic Substances on the Rheological Properties of Paints and Varnishes By using suitable added substances, the flow behaviour of paints and varnishes is so regulated, that thixotropic systems arise. The mode of operation of these thixotropic added substances is dependent on some of the lacquer-reception factors (oil content, pigment composition, filler particles etc.).

The carotenoid composition of the red and yellow cashew-apples and two commercial brands of pasteurized juice were determined by column and thin-layer chromatography, visible absorption spectroscopy and specific chemical reactions. Alpha-carotene, β-carotene, ζ-carotene, cis-β-carotene, cryptoxanthin, aurochrome, cryptochrome, and auroxanthin were identified in all samples, with β-carotene as the predominant pigment. Color differences reflected the total amount, not the type of carotenoid present. Geographic effects on the pigment composition did not appear to be appreciable. In the processed juice, the total carotenoid content and vitamin A value were lower but the epoxide level higher. No quantitative differences were noted among lots of the same brand or between brands of pasteurized juice.

The physiological changes in the green alga Spongiochloris typica were followed in liquid and agar for 8 weeks. Agar cultures changed drastically in lipid content, pigment composition, and heat and desiccation resistance. Changes in liquid cultures were gradual and not as extreme as those of agar cultures. However, rate and extent of dry-weight increments were similar in liquid and on agar. Liquid cultures are seemingly more stable in the physiological responses than are agar cultures where the environmental changes are conspicuous.