Benzimidazolone-Dioxazine Pigments-Based Conjugated Polymers for Organic Field-Effect Transistor

Molecules based on benzimidazolone-dioxazine are known as blue/violet pigments and have been commercialized for decades. However, unfavorable solubility limits the application of these structures as building blocks of conjugated polymers despite their low band gaps. Herein, a series of donor-acceptor conjugated polymers containing soluble benzimidazolone-dioxazine structures as the acceptors and oligothiophene as donors are synthesized and investigated. With increasing numbers of thiophene rings, the steric hindrance diminishes and high molecular weight polymers can be achieved, leading to an improved performance in organic field effect transistor devices. The hole mobility of polymers with three to six thiophene units is in the order of 10^-1 cm² V^-1 s ^-1 . Among all the polymers, polymer P3 with three thiophene units between benzimidazolone-dioxazine structures shows the best hole mobility of 0.4 cm² V^-1 s ^-1 . Grazing-incidence wide-angle X-ray scattering results reveal that the high mobility of organic field-effect transistors (OFETs) can be accredited by matched donor-acceptor packing in the solid thin films.

Protein-binding approaches for improving bioaccessibility and bioavailability of anthocyanins

Color is an important characteristic of food. Over the last 15 years, more attention has been paid to natural colorants because of the rising demand for clean-label food products. Anthocyanins, which are a group of phytochemicals responsible for the purple, blue or red hues of many plants, offer a market advantage. In addition, anthocyanin-rich foods are associated with protection against cardiovascular disease, thrombosis, diabetes, cancer, microbial-based disorders, neurological disorders, and vision ailments. However, the real health value of anthocyanins, whether as a natural colorant or a functional ingredient, is dependent on the ultimate bioaccessibility and bioavailability in the human body. Many animal and human clinical studies revealed that, after intake of anthocyanin-rich foods or anthocyanin extracts, only trace amounts (< 1% of ingested content) of anthocyanins or their predicted metabolites were detected in plasma after a standard blood draw, which was indicative of low bioavailability of anthocyanins. Protein binding to anthocyanins is a strategy that has recently been reported to enhance the ultimate bioactivity, bioaccessibility, and bioavailability of anthocyanins as compared to anthocyanins delivered without a protein carrier. Therefore, in this review, we address anthocyanin properties in food processing and digestion, anthocyanin-protein complexes used in food matrices, and changes in the bioaccessibility and bioavailability of anthocyanins when bound into anthocyanin-protein complexes in foods. Finally, we summarize the challenges and prospects of this delivery system for anthocyanin pigments.

Chemical characterization of yellow-orange and purple varieties of Opuntia ficus-indica fruits and thermal stability of their betalains

Betalains are plant pigments with biological properties and can be used instead of synthetic colorants to confer color and functional properties to foods. The objective of this work was to carry out the chemical characterization of two varieties of prickly pear of Opuntia ficus-indica, one of yellow-orange coloration (Mandarina) and the other of purple coloration (Vigor), through measurements of chemical parameters and color in pulp, antioxidant activity, total phenolic compounds, and betalain content. Considering the thermolability of betalains and their potential applications in food, the thermal stability and activation energy of betacyanins from Vigor variety and betaxanthins from the Mandarina variety were also evaluated and compared with those from beetroot, the main source of betalains. Results for chemical characterization agreed with previous prickly pear reports of other regions, while the thermal degradation kinetics of betalains showed a first-order degradation pattern with respect to time and temperature treatment. Betacyanins from Vigor prickly pear showed similar thermal stability to those from beetroot, which was reflected in similar values of activation energy, while betaxanthins from Mandarina prickly pear showed a higher stability, and therefore a higher activation energy, than those from beetroot. Based on the results, the prickly pear varieties used in this study can be considered as a good source of betalains with potential applications in food and, in addition, the methodology for the evaluation of thermostability can be used to compare the stability of betalains from different sources in a temperature range of 50-90°C. PRACTICAL APPLICATION: The varieties of prickly pear used in this study can be considered a good source of red-purple and yellow-orange easily extractable pigments. In addition, we report a methodology that can be used for the evaluation of the thermal stability of these pigments and to compare this stability between different plant sources. Gaining knowledge on betalain thermal stability will make it possible to propose specific applications, for example, in processed foods requiring different pigment stabilities.

Physio-Biochemical Responses of Sweet Cherry Leaf to Natural Cold Conditions

Trees of the sweet cherry cultivar 'Grace Star' (Prunus avium L.) were exposed to low temperatures without frost for two consecutive nights under natural conditions 36 d after flowering, to study the effects on the physiological properties and metabolic status of leaves. The response was studied by measuring chlorophyll fluorescence and gas exchange parameters and by analyzing chloroplast pigments (i) immediately after exposure, (ii) 24 h and (iii) 48 h later. The first exposure at 2.4 (±0.2) °C and a minimum of 0.8 °C elicited more changes than the second exposure at 4.9 (±0.3) °C and a minimum of 2.4 °C. After the first exposure, the maximum quantum yield of PS II (Fv/Fm), effective quantum efficiency of PS II, net photosynthesis (P_N), stomatal conductance (g_s), transpiration, and intercellular CO₂ concentration were significantly lower, and after the second exposure, the content of chlorophyll b, total chlorophyll, β-carotene, and lutein were lower. The content of antheraxanthin and zeaxanthin was higher immediately after both exposures, and that of antheraxanthin was also higher 24 h later. Recovery took longer in trees that were exposed twice. Fv/Fm recovered within 48 h, but the de-epoxidation state of the xanthophyll cycle pool, P_N, and g_s did not reach the level of controls, indicating that the stress effect lasted several days which is probably sufficient to cause fruit drop and reduce yield.

Eco-Evo-Devo of petal pigmentation patterning

Colourful spots, stripes and rings decorate the corolla of most flowering plants and fulfil important biotic and abiotic functions. Spatial differences in the pigmentation of epidermal cells can create these patterns. The last few years have yielded new data that have started to illuminate the mechanisms controlling the function, formation and evolution of petal patterns. These advances have broad impacts beyond the immediate field as pigmentation patterns are wonderful systems to explore multiscale biological problems: from understanding how cells make decisions at the microscale to examining the roots of biodiversity at the macroscale. These new results also reveal there is more to petal patterning than meets the eye, opening up a brand new area of investigation. In this mini-review, we summarise our current knowledge on the Eco-Evo-Devo of petal pigmentation patterns and discuss some of the most exciting yet unanswered questions that represent avenues for future research.

Enhancing Bioproducts in Seaweeds via Sustainable Aquaculture: Antioxidant and Sun-Protection Compounds

Marine macroalgae are considered an untapped source of healthy natural metabolites and their market demand is rapidly increasing. Intertidal macroalgae present chemical defense mechanisms that enable them to thrive under changing environmental conditions. These intracellular chemicals include compounds that can be used for human benefit. The aim of this study was to test cultivation protocols that direct seaweed metabolic responses to enhance the production of target antioxidant and photoprotective biomaterials. We present an original integrated multi-trophic aquaculture (IMTA) design, based on a two-phase cultivation plan, in which three seaweed species were initially fed by fish effluents, and subsequently exposed to various abiotic stresses, namely, high irradiance, nutrient starvation, and high salinity. The combined effect of the IMTA's high nutrient concentrations and/or followed by the abiotic stressors enhanced the seaweeds' content of mycosporine-like amino acids (MAAs) by 2.3-fold, phenolic compounds by 1.4-fold, and their antioxidant capacity by 1.8-fold. The Sun Protection Factor (SPF) rose by 2.7-fold, and the chlorophyll and phycobiliprotein synthesis was stimulated dramatically by an order of magnitude. Our integrated cultivation system design offers a sustainable approach, with the potential to be adopted by emerging industries for food and health applications.

Characterization of New Egyptian Linseed Varieties and the Effects of Roasting on Their Pigments, Tocochromanols, Phytosterols, Omega-3 Fatty Acids, and Stability

The purpose of this study was to explore the effects of roasting linseeds on the pigment, lipid profile, bioactive components, and oxidative stability of the extracted oils. The linseed varieties Giza 11, Giza 12, Sakha 3, and Sakha 6 were roasted at 180 °C for 10 min, and the oils were extracted by cold pressing. The results showed that, after roasting, there was an increase in oil percentage and peroxide value, as well as small increases in p-anisidine and acid values. Roasting also caused an increase in chlorophyll content, while lutein and β-carotene tend to slightly decrease, except in the Giza 11 variety. The total phenolics content was markedly enhanced after roasting. Omega-3 fatty acids were not affected by the roasting process. The total amounts of tocochromanol were found to decrease in the Giza 12 and Sakha 6 varieties after roasting. Plastochromanol-8 increased in all varieties after roasting. The phytosterol composition was minimally affected by roasting. Roasting enhanced the stability of the extracted oils, increasing the induction period and decreasing EC50 values. These results may thus help to discriminate between the different linseed varieties and serve to recommend the use of roasting to enhance the oxidative stability of extracted oil.

Effect of Solid-State Fermentation on Vitamin C, Photosynthetic Pigments and Sugars in Willow Herb (Chamerion angustifolium (L.) Holub) Leaves

The goal of this investigation was to establish the impact of solid-state fermentation of different durations on the quantitative changes of vitamin C, sugars and photosynthetic pigments in the leaves of willow herbs. The tested leaves were fermented using two solid-state fermentation methods (aerobic and anaerobic) for different time periods (unfermented and fermented for 24, 48 and 72 h). The quantitative and qualitative composition of chlorophylls, carotenoids, sugars and vitamin C were determined using high performance liquid chromatography (HPLC) with UV detectors. Results indicated that aerobic and anaerobic solid-state fermentation significantly decreased the contents of vitamin C, dehydroascorbic and L-ascorbic acids in leaves compared with the unfermented leaves. The contents of total chlorophyll and chlorophyll a were the highest in unfermented leaves and after 24 h of aerobic solid-state fermentation. The maximum content of total carotenoids in leaves were after 48 and 72 h of aerobic solid-state fermentation (149.31 mg 100 g^-1 and 151.51 mg 100 g^-1, respectively). The application of anaerobic solid-state fermentation resulted in significant increase in the content of total sugars, fructose and glucose in investigated samples. In conclusion, optimization of fermentation parameters allows increasing the content of sugars and photosynthetic pigments in leaves of willow herbs.

The Effect of Background Color on Skin Color Variation of Juvenile Plectropomus leopardus

Fish skin color is usually strongly affected by the background color of their environment. The study investigated the effects of five different background colors on the skin color of leopard coral groupers (Plectropomus leopardus). More than 450 juveniles were reared in Blue, Red, Black, White, and Transparent background tanks for 56 days. The paraffin section showed that the skin melanin zone of fish in the White group was smaller, whereas the Black and Red groups (especially Black) were nearly the largest. The apparent skin color of P. leopardus was red on the white background, which darkened in response to the other color backgrounds. The Black group revealed the blackest skin color, followed by the transparent group. Moreover, the White group had the highest L*, a*, and b* values. The melanin content and tyrosinase activity in the dorsal and ventral skin of the Black group were significantly higher than those in the other groups (p < 0.05), and the serum α-MSH level was higher in the Black group as well. The carotenoid and lutein contents showed completely different trends among the experimental groups, as carotenoid content was higher in the Red and White groups, while lutein content was higher in the Transparent group. The expression level of scarb1 was highest in the Blue and White groups, followed by the Transparent group, and lowest in the Black group (p < 0.05). The expression trend of scarb1 was similar to the skin color in different backgrounds, indicating that the background color regulated scarb1 expression level through visual center, then influenced the uptake and transport of carotenoids, then influenced the skin color formation of P. leopardus. Moreover, lighter colors inhibited the formation of melanocytes and had a significant effect on carotenoid and lutein contents. Pigment-related genes were involved in the regulation of fish skin color, and they were affected by background color in P. leopardus. These results indicate that a white background is more conducive to maintaining red skin color in juvenile P. leopardus.

Chemical Profiling, Antiproliferative and Antimigratory Capacity of Haberlea rhodopensis Extracts in an In Vitro Platform of Various Human Cancer Cell Lines

Haberlea rhodopensis is a Balkan endemic plant that belongs to the Gesneriaceae family, and is believed to have medicinal use and health-promoting properties. This study aimed to (i) prepare aqueous (HAE) and ethanolic (HEE) extracts from the leaves of H. rhodopensis from in vitro propagated plants, (ii) screen for their potential antiproliferative and antimigratory activities, and (iii) chemically characterize both HAE and HEE by identifying compounds which may contribute to their observed bioactivity thereby further supporting their potential use in biomedical applications. The antiproliferative activity of both extracts was assessed against six human cancer cell lines by employing the sulforhodamine-B (SRB) assay. HEE was found to be more potent in inhibiting cancer cell growth as compared to HAE. Therefore, HEE's antimigratory effects were further studied in hepatocellular carcinoma (HepG2) and non-small cell lung adenocarcinoma (A459) cell lines as they were among the most sensitive ones to its antiproliferative activity. HEE was found to exert significant antimigratory concentration-dependent effects in both cell lines assessed with the wound healing assay. Chemical characterization by UPLC-MS/MS analysis identified that HEE contains higher levels of flavonoids, phenolic compounds, pigments (chlorophyll-/-b, lycopene, and β-carotene), monoterpenoids, and condensed tannins compared to HAE, while HAE, contains higher levels of soluble protein and sugars. Furthermore, HEE demonstrated remarkable antioxidant activity evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH^●), 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS^●+) and ferric reducing/antioxidant power (FRAP) assays. We have obtained comprehensive results highlighting the potential of HEE as a source of bioactive compounds with anticancer properties. Future studies should aim at identifying the chemical constituents responsible for the bioactivities observed, and focus on investigating HEE's effects, in in vivo preclinical cancer models.

Using leaf spectroscopy and pigment estimation to monitor indoor grown lettuce dynamic response to spectral light intensity

Rising urban food demand is being addressed by plant factories, which aim at producing quality food in closed environment with optimised use of resources. The efficiency of these new plant production systems could be further increased by automated control of plant health and nutritious composition during cultivation, allowing for increased produce value and closer match between plant needs and treatment application with potential energy savings. We hypothesise that certain leaf pigments, including chlorophylls, carotenoids and anthocyanins, which are responsive to light, may be good indicator of plant performance and related healthy compounds composition and, that the combination of leaf spectroscopy and mathematical modelling will allow monitoring of plant cultivation through noninvasive estimation of leaf pigments. Plants of two lettuce cultivars (a green- and a red-leaf) were cultivated in hydroponic conditions for 18 days under white light spectrum in climate controlled growth chamber. After that period, plant responses to white light spectrum ('W') with differing blue wavelengths ('B', 420 - 450 nm) percentage (15% 'B15', and 40% 'B40') were investigated for a 14 days period. The two light spectral treatments were applied at photon flux densities (PFDs) of 160 and 240 µmol m^-2 s^-1, resulting in a total of four light treatments (160WB15, 160WB40, 240WB15, 240WB40). Chlorophyll a fluorescence measurements and assessment of foliar pigments, through destructive (in vitro) and non-destructive (in vivo) spectrophotometry, were performed at 1, 7 and 14 days after treatment initiation. Increase in measured and estimated pigments in response to WB40 and decrease in chlorophyll:carotenoid ratio in response to higher PFD were found in both cultivars. Cultivar specific behavior in terms of specific pigment content stimulation in response to time was observed. Content ranges of modelled and measured pigments were comparable, though the correlation between both needs to be improved. In conclusion, leaf pigment estimation may represent a potential noninvasive and real-time technique to monitor, and control, plant growth and nutritious quality in controlled environment agriculture.

Improvement in the Sequential Extraction of Phycobiliproteins from Arthrospira platensis Using Green Technologies

Arthrospira platensis (commercially known as Spirulina) is an excellent source of phycobiliproteins, especially C-phycocyanin. Phycobiliproteins are significant bioactive compounds with useful biological applications. The extraction process plays a significant role in downstream microalga production and utilisation. The important pigments found in A. platensis include chlorophyll and carotenoids as nonpolar pigments and phycobiliproteins as polar pigments. Supercritical fluid extraction (SFE) as a green extraction technology for the high-value metabolites of microalgae has potential for trends in food and human health. The nonpolar bioactive compounds, chlorophyll and carotenoids of A. platensis, were primarily separated using supercritical carbon dioxide (SC-CO₂) solvent-free fluid extraction pressure; the temperature and ethanol as cosolvent conditions were compared. The residue from the A. platensis cells was subjected to phycobiliprotein extraction. The phosphate and water extraction of A. platensis SFE residue were compared to evaluate phycobiliprotein extraction. The SFE results exhibited higher pressure (350 bar) and temperature extraction (50 °C) with ethanol-free extraction and increased nonpolar pigment. Phycobiliprotein yield was obtained from A. platensis SFE residue by ethanol-free buffer extraction as a suitable process with antioxidant properties. The C-phycocyanin was isolated and enhanced to 0.7 purity as food grade. This developed method can be used as a guideline and applied as a sustainable process for important pigment extraction from Arthrospira microalgae.

Zinc biofortification of hydroponically grown basil: Stress physiological responses and impact on antioxidant secondary metabolites of genotypic variants

Ocimum basilicum L. is an aromatic plant rich in bioactive metabolites beneficial to human health. The agronomic biofortification of basil with Zn could provide a practical and sustainable solution to address Zn deficiency in humans. Our research appraised the effects of biofortification implemented through nutrient solutions of different Zn concentration (12.5, 25.0, 37.5, and 50 µM) on the yield, physiological indices (net CO₂ assimilation rate, transpiration, stomatal conductance, and chlorophyll fluorescence), quality, and Zn concentration of basil cultivars 'Aroma 2' and 'Eleonora' grown in a floating raft system. The ABTS, DPPH, and FRAP antioxidant activities were determined by UV-VIS spectrophotometry, the concentrations of phenolic acids by mass spectrometry using a Q Extractive Orbitrap LC-MS/MS, and tissue Zn concentration by inductively coupled plasma mass spectrometry. Although increasing the concentration of Zn in the nutrient solution significantly reduced the yield, this reduction was less evident in 'Aroma 2'. However, regardless of cultivar, the use of the maximum dose of Zn (50 µM) increased the concentration of carotenoids, polyphenols, and antioxidant activity on average by 19.76, 14.57, and 33.72%, respectively, compared to the Control. The significant positive correlation between Zn in the nutrient solution and Zn in plant tissues underscores the suitability of basil for soilless biofortification programs.

In Living Color: Pigment-Based Microbial Ecology At the Mineral-Air Interface

Pigment-based color is one of the most important phenotypic traits of biofilms at the mineral-air interface (subaerial biofilms, SABs), because it reflects the physiology of the microbial community. Because color is the hallmark of all SABs, we argue that pigment-based color could convey the mechanisms that drive microbial adaptation and coexistence across different terrestrial environments and link phenotypic traits to community fitness and ecological dynamics. Within this framework, we present the most relevant microbial pigments at the mineral-air interface and discuss some of the evolutionary landscapes that necessitate pigments as adaptive strategies for resource allocation and survivability. We report several pigment features that reflect SAB communities' structure and function, as well as pigment ecology in the context of microbial life-history strategies and coexistence theory. Finally, we conclude the study of pigment-based ecology by presenting its potential application and some of the key challenges in the research.

High Ecophysiological Plasticity of Desmarestia aculeata (Phaeophyceae) Present in an Arctic Fjord under Varying Salinity and Irradiance Conditions

The seaweed Desmarestia aculeata (Phaeophyceae) is distributed in the temperate zone of the North Atlantic up to the Arctic, where it is exposed to a high Arctic light regime and fluctuating salinity conditions resulting from glacial and terrestrial run-off. Information on how this species is able to thrive under current and future Arctic conditions is scarce. During the Arctic summer of 2019, D. aculeata was collected in Kongsfjorden, Svalbard (78.9° N, 11.9° E) to investigate its physiological and biochemical responses to variations in salinity (salinities: 34, 28 and 18) and daily cycles of irradiance (50-500 μmol photons m^-2s^-1) at 0 °C over 21 days. The species revealed effective short-term acclimation to both abiotic drivers. Maximal quantum yield of PSII (F_v/F_m) fluctuated with the light cycle at a salinity of 34, while the maximum relative electron transport rate (rETRmax) significantly differed between salinities of 28 and 18. Chlorophyll a and β-Carotene remained at high concentrations in all treatments showing pronounced acclimation during the experiment. High mannitol concentrations were measured throughout the experiment, while phlorotannins were high at low salinity. Hyposalinity and light are interacting drivers of the physiological and biochemical acclimation process for D. aculeata. Our experiment highlights the high ecophysiological plasticity of D. aculeata, suggesting that the species will likely be capable of withstanding future habitat changes in the Arctic.

Impact of Growth Phase, Pigment Adaptation, and Climate Change Conditions on the Cellular Pigment and Carbon Content of Fifty-One Phytoplankton Isolates

Owing to their importance in aquatic ecosystems, the demand for models that estimate phytoplankton biomass and community composition in the global ocean has increased over the last decade. Moreover, the impacts of climate change, including elevated carbon dioxide (CO₂ ), increased stratification, and warmer sea surface temperatures, will likely shape phytoplankton community composition in the global ocean. Chemotaxonomic methods are useful for modeling phytoplankton community composition from marker pigments normalized to chlorophyll a (Chl a). However, photosynthetic pigments, particularly Chl a, are sensitive to nutrient and light conditions. Cellular carbon is less sensitive, so using carbon biomass instead may provide an alternative approach. To this end, cellular pigment and carbon concentrations were measured in 51 strains of globally relevant, cultured phytoplankton. Pigment-to-Chl a and pigment-to-carbon ratios were computed for each strain. For 25 strains, measurements were taken during two growth phases. While some differences between growth phases were observed, they did not exceed within-class differences. Multiple strains of Amphidinium carterae, Ditylum brightwellii and Heterosigma akashiwo were measured to determine whether time in culture influenced pigment and carbon composition. No appreciable trends in cellular pigment or carbon content were observed. Lastly, the potential impact of climate change conditions on the pigment ratios was assessed using a multistressor experiment that included increased mean light, temperature, and elevated pCO₂ on three species: Thalassiosira oceanica, Ostreococcus lucimarinus, and Synechococcus. The largest differences were observed in the pigment-to-carbon ratios, while the marker pigments largely covaried with Chl a. The implications of these observations to chemotaxonomic applications are discussed.

Cell adaptation of the extremophilic red microalga Galdieria sulphuraria to the availability of carbon sources

Global energy demand and fossil fuels impact on climate can be partially managed by an increase in the use of biofuels for transports and industries. Biodiesel production is generally preceded by a transesterification process of the green biomass triacylglycerols that generates large amounts of glycerol as a by-product. In this study, the extremophilic red microalga Galdieria sulphuraria 074W was cultivated in heterotrophy. The microalgal growth parameters and biomass composition were compared when grown on an equivalent molar concentration of carbon of either glucose or glycerol as unique carbon source. The maximal biomass reached in these two conditions was not significantly different (∼2.5 g.L^-1). Fatty acid profile, protein and storage carbohydrate contents were also statistically similar, irrespectively of the metabolized carbon source. We also observed that the pigment content of G. sulphuraria cells decreased during heterotrophic growth compared to photoautotrophic cultivated cells, and that this diminution was more important in the presence of glucose than glycerol: cells were yellowish in the presence of glucose and green in the presence of glycerol. The pigmentation was restored when glucose was totally consumed in the medium, suggesting that the presence of glucose repressed pigment synthesis. Based on this observation, a transcriptome analysis was performed in order to better understand the mechanisms involved in the loss of color mediated by darkness and by glucose in G. sulphuraria. Three conditions were analyzed: heterotrophy with glycerol or glucose and phototrophy. This allowed us to understand the transcriptional response of cells to light and dark environments both at the nuclear and chloroplast levels, and to show that transcription of gene families, acquired by horizontal gene transfer, such as sugar, amino acid, or acetate transporters, were involved in the response to the availability of different (in)organic sources.

New species of Sticta (lichenised Ascomycota, lobarioid Peltigeraceae) from Bolivia suggest a high level of endemism in the Central Andes

Six species of Sticta are described as new to science on the basis of material from Bolivia and supported by phylogenetic analysis of the fungal ITS barcoding marker. The species were resolved in all three of the clades (I, II, III) widespread and common in the Neotropics, as defined in an earlier study on the genus. Comparison with material from neighbouring countries (i.e. Colombia, Ecuador, Peru) suggests that these new species may be potentially endemic to the Bolivian Yungas ecoregion. For each species, a detailed morphological and anatomical description is given. Stictaamboroensis Ossowska, Kukwa, B. Moncada & Lücking is a medium-sized green-algal species with laminal to submarginal apothecia with hirsute margins and with light to dark brown lower tomentum. Stictaaymara Ossowska, Kukwa, B. Moncada, Flakus, Rodriguez-Flakus & Lücking is a comparatively small cyanobacterial taxon with Nostoc as photobiont, laminal, richly branched, aggregate isidia and a golden to chocolate-brown lower tomentum. The medium-sized, cyanobacterial S.bicellulata Ossowska, Kukwa, B. Moncada & Lücking has cyanobacterial photobiont, bicellular ascospores, apothecia with white to golden-brown hairs on the margins, K+ violet apothecial margin (ring around disc) and epihymenium and a white to dark brown lower tomentum. In contrast, the green-algal species, S.carrascoensis Ossowska, Kukwa, B. Moncada & Lücking is characterised by its large size, apothecia with dark brown hairs on the margins and a yellow medulla. The cyanobacterial S.catharinae Ossowska, B. Moncada, Kukwa, Flakus, Rodriguez-Flakus & Lücking forms stipitate thalli with Nostoc as photobiont, abundant, laminal to submarginal apothecia and a golden-brown lower tomentum. Finally, the cyanobacterial S.pseudoimpressula Ossowska, Kukwa, B. Moncada & Lücking produces laminal apothecia with an orange-yellow line of pruina along the margins which reacts K+ carmine-red. In addition to the six new Bolivian taxa, the cyanobacterial S.narinioana B. Moncada, Ossowska & Lücking is described as new from Colombia and it represents the closely-related sister species of the Bolivian S.aymara; it differs from the latter largely in the marginal instead of laminal isidia.

Study and Characterization of Special Gypsum-Based Pastes for Their Use as a Replacement Material in Architectural Restoration and Construction

Within the construction sector, the use of gypsum-based pastes features in the majority of monuments, giving this material significant relevance in conservation and restoration projects affecting the world's cultural heritage. In this research, we evaluated special gypsum-based colored pastes mixed with air lime, hydraulic lime and sodium silicate, and eight different pigments for their use as replacement materials in architectural restoration and construction. We analyzed the suitability of their physical and chemical properties and their hydric characteristics, mechanics and colorimetric implications in two different studies after 28 days and 120 days. The characterization of the products has mainly confirmed the suitability of the pastes containing pigments for use in the most common applications for these kinds of mixes, highlighting that their specific capacities are worth leveraging. The crystallization of gypsum minerals, observed in all of the mixes, helps to consolidate the shrinkage cracks which appear inside the pastes, improving their mechanical strength values. Another observation of the pastes is related to the amorphous silica precipitates in the mixes which contained sodium silicate: the latter provided to them good mechanical behavior. The improvement observed in the pastes containing the green earth pigment is substantial, due to the inclusion of aluminum silicates and Mg, which is partly responsible for the increased compressive strength of the pastes. Finally, the colorimetric analysis is of vital importance in determining the loss of intensity of the colors of the pastes used, since subjective observation leads to serious errors of interpretation.

Distinguishing Genuine Imperial Qing Dynasty Porcelain from Ancient Replicas by On-Site Non-Invasive XRF and Raman Spectroscopy

The combined use of non-invasive on-site portable techniques, Raman microscopy, and X-ray fluorescence spectroscopy on seven imperial bowls and two decorated dishes, attributed to the reigns of the Kangxi, Yongzheng, Qianlong, and Daoguang emperors (Qing Dynasty), allows the identification of the coloring agents/opacifiers and composition types of the glazes and painted enamels. Particular attention is paid to the analysis of the elements used in the (blue) marks and those found in the blue, yellow, red, and honey/gilded backgrounds on which, or in reserve, a floral motif is principally drawn. The honey-colored background is made with gold nanoparticles associated with a lead- and arsenic-based flux. One of the red backgrounds is also based on gold nanoparticles, the second containing copper nanoparticles, both in lead-based silicate enamels like the blue and yellow backgrounds. Tin and arsenic are observed, but cassiterite (SnO₂) is clearly observed in one of the painted decors (dish) and in A676 yellow, whereas lead (calcium/potassium) arsenate is identified in most of the enamels. Yellow color is achieved with Pb-Sn-Sb pyrochlore (Naples yellow) with various Sb contents, although green color is mainly based on lead-tin oxide mixed with blue enamel. The technical solutions appear very different from one object to another, which leads one to think that each bowl is really a unique object and not an item produced in small series. The visual examination of some marks shows that they were made in overglaze (A608, A616, A630, A672). It is obvious that different types of cobalt sources were used for the imprinting of the marks: cobalt rich in manganese for bowl A615 (Yongzheng reign), cobalt rich in arsenic for bowl A613 (but not the blue mark), cobalt with copper (A616), and cobalt rich in arsenic and copper (A672). Thus, we have a variety of cobalt sources/mixtures. The high purity of cobalt used for A677 bowl indicates a production after ~1830-1850.

Partial replacement of soybean meal with Chlorella vulgaris in broiler diets influences performance and improves breast meat quality and fatty acid composition

Alternative feed ingredients, such as microalgae, may be more sustainable in comparison to conventional feedstuffs that need large amounts of arable land and are often imported. This study evaluates the effects of Chlorella vulgaris various inclusion levels in the diet of broiler chickens on performance, carcass yield, organ measurements, breast meat quality, fatty acids profile, and antioxidant capacity. A total of two hundred forty 5 d old male Ross 308 broilers were randomly allotted to 4 groups (6 replicates of 10 birds each). Each group received either a control diet or a diet where soybean meal was replaced with 10% (CV10%), 15% (CV15%), or 20% C. vulgaris for 40 d. Performance parameters, carcass and meat traits were evaluated. Compared to the control group, birds supplemented with C. vulgaris (15% and 20%) had lower body weight, weight gain, and feed intake (P < 0.0001), whereas no differences were observed between the control and CV10% groups (P > 0.05). Feed conversion ratio did not differ between control and CV groups. Diets containing C. vulgaris significantly increased ileal digesta viscosity, weight and size of several gastrointestinal compartments, as well as breast muscle yield (P < 0.0001). Incorporation of C. vulgaris resulted in yellower breast muscle (P < 0.0001), with significantly increased chlorophyll a (P < 0.05), chlorophyll b, and total carotenoids contents (P < 0.0001). Inclusion of C. vulgaris decreased bacterial count in meat samples in comparison to controls (P < 0.0001). A 20% C. vulgaris inclusion resulted in higher water holding capacity (P < 0.05) and lower cooking loss (P < 0.05). As dietary C. vulgaris increased, concentrations of DHA + EPA (P < 0.05) and n-3 PUFA (P < 0.0001) increased in breast meat, while the n-6/n-3 PUFA ratio decreased (P < 0.0001). Sensory analysis showed that breast meat from the CV10% group had the highest acceptance score. Overall, dietary concentrations of C. vulgaris of up to 20% improve breast meat quality, whereas 10% of C. vulgaris inclusion is recommended.

A Straightforward Access to New Amides of the Melanin Precursor 5,6-Dihydroxyindole-2-carboxylic Acid and Characterization of the Properties of the Pigments Thereof

We report herein an optimized procedure for preparation of carboxamides of 5,6-dihydroxyindole-2-carboxylic acid (DHICA), the main biosynthetic precursor of the skin photoprotective agents melanins, to get access to pigments with more favorable solubility properties with respect to the natural ones. The developed procedure was based on the use of a coupling agent (HATU/DIPEA) and required protection of the catechol function by easily removable acetyl groups. The O-acetylated compounds could be safely stored and taken to the reactive o-diphenol form just before use. Satisfactorily high yields (>85%) were obtained for all amides. The oxidative polymerization of the synthesized amides carried out in air in aqueous buffer at pH 9 afforded melanin-like pigmented materials that showed chromophores resembling those of DHICA-derived pigments, with a good covering of the UVA and the visible region, and additionally exhibited a good solubility in alcoholic solvents, a feature of great interest for the exploitation of these materials as ingredients of dermocosmetic formulations.

Plankton Imagery Data Inform Satellite-Based Estimates of Diatom Carbon

Estimating the biomass of phytoplankton communities via remote sensing is a key requirement for understanding global ocean ecosystems. Of particular interest is the carbon associated with diatoms given their unequivocal ecological and biogeochemical roles. Satellite-based algorithms often rely on accessory pigment proxies to define diatom biomass, despite a lack of validation against independent diatom biomass measurements. We used imaging-in-flow cytometry to quantify diatom carbon in the western North Atlantic, and compared results to those obtained from accessory pigment-based approximations. Based on this analysis, we offer a new empirical formula to estimate diatom carbon concentrations from chlorophyll a. Additionally, we developed a neural network model in which we integrated chlorophyll a and environmental information to estimate diatom carbon distributions in the western North Atlantic. The potential for improving satellite-based diatom carbon estimates by integrating environmental information into a model, compared to models that are based solely on chlorophyll a, is discussed.

A computational chemistry-driven hypothesis on the mode of action of Hipposudoric Acid and related analogs

Aim: To elucidate the mode of action of the hipposudoric acid derivatives and identify hit compounds for synthesis. Materials & methods: Structural fragments of known bioactive fluorenes were introduced onto the hipposudoric acid scaffold to yield novel derivatives. The binding motifs of the novel compounds were compared to the pharmacophore of DHFR co-crystallized with Methotrexate (MTX). Results: Several of the novel compounds showed binding affinities that exceeded the affinity of the docked endogenous ligand (dihydrofolic acid). Conclusion: This study indicates that compounds 3r₁₂, 3r₉, 1s₉ and 3r₁₀ are promising candidates for synthesis and pharmacological evaluation.

Drying Microalgae Using an Industrial Solar Dryer: A Biomass Quality Assessment

Microalgae are considered a promising resource of proteins, lipids, carbohydrates, and other functional biomolecules for food and feed markets. Competitive drying solutions are required to meet future demands for high-quality algal biomass while ensuring proper preservation at reduced costs. Since often used drying methods, such as freeze or spray drying, are energy and time consuming, more sustainable processes remain to be developed. This study tested an indirect and hybrid solar dryer as an alternative to conventional freeze drying of industrially produced Tetraselmis chui and Nannochloropsis oceanica wet paste. The effects of the drying method on biomass quality parameters, including biochemical profiles, functional properties, and microbial safety, were assessed. No significant differences were found between the applied drying technologies for total proteins, carbohydrates, lipids, and fatty acid profiles. On the other hand, some pigments showed significant differences, displaying up to 44.5% higher contents in freeze-dried samples. Minor differences were also registered in the mineral profiles (<10%). Analyses of microbial safety and functional properties of the solar-dried biomass appear adequate for food and feed products. In conclusion, industrial solar drying is a sustainable technology with a high potential to preserve high-quality microalgal biomass for various markets at expected lower costs.