Preservation Of Pigments Research Articles

Salicylic Acid Priming Improves Cotton Seedling Heat Tolerance through Photosynthetic Pigment Preservation, Enhanced Antioxidant Activity, and Osmoprotectant Levels.

The escalating global temperatures associated with climate change are detrimental to plant growth and development, leading to significant reductions in crop yields worldwide. Our research demonstrates that salicylic acid (SA), a phytohormone known for its growth-promoting properties, is crucial in enhancing heat tolerance in cotton (Gossypium hirsutum). This enhancement is achieved through modifications in various biochemical, physiological, and growth parameters. Under heat stress, cotton plants typically show significant growth disturbances, including leaf wilting, stunted growth, and reduced biomass. However, priming cotton plants with 1 mM SA significantly mitigated these adverse effects, evidenced by increases in shoot dry mass, leaf-water content, and chlorophyll concentrations in the heat-stressed plants. Heat stress also prompted an increase in hydrogen peroxide levels-a key reactive oxygen species-resulting in heightened electrolyte leakage and elevated malondialdehyde concentrations, which indicate severe impacts on cellular membrane integrity and oxidative stress. Remarkably, SA treatment significantly reduced these oxidative stresses by enhancing the activities of critical antioxidant enzymes, such as catalase, glutathione S-transferase, and ascorbate peroxidase. Additionally, the elevated levels of total soluble sugars in SA-treated plants enhanced osmotic regulation under heat stress. Overall, our findings reveal that SA-triggered protective mechanisms not only preserve photosynthetic pigments but also ameliorate oxidative stress and boost plant resilience in the face of elevated temperatures. In conclusion, the application of 1 mM SA is highly effective in enhancing heat tolerance in cotton and is recommended for field trials before being commercially used to improve crop resilience under increasing global temperatures.

Effect of Temperature on Photosynthetic Pigment Degradation during Freeze–Thaw Process of Postharvest of Celery Leaves

Celery (Apium graveolens L.) is a kind of green leaf vegetable with a large consumption demand in the food industry. It is a commonly used material in quick-frozen food stuffing such as dumplings and steamed stuffed. Fresh celery leaf blades and petioles are rich in photosynthetic pigments including chlorophyll and carotenoid, their contents are closely related to the quality of celery and its products. In order to explore the effects of freezing and thawing temperature and thawing time on the degradation of photosynthetic pigments in celery leaf blades and petioles, the changes in photosynthetic pigments during thawing storage were measured under different freezing and thawing temperatures. The results showed that lower freezing and thawing temperatures were beneficial to the preservation of photosynthetic pigments in celery leaf blades and petioles, and the loss of photosynthetic pigments enhanced with the increase in thawing temperature and thawing time. Under the cold storage condition of −80 °C, the loss rate of pigment substances can be reduced by nearly 20% compared with that of −18 °C, and −80 °C and 4 °C could be the best temperature combination of freezing and thawing. The content and degradation rate of photosynthetic pigments in celery leaf blades were higher than that in petioles during thawing, with a total chlorophyll loss rate reaching 35% during 6 to 12 h after thawing. The increase in temperature difference between freezing and thawing could aggravate the damage to the cell structure and the degradation of the pigment, as chlorophyll is more sensitive to temperature changes, and the degradation rate is significantly higher than that of carotenoids. From the perspective of delaying the degradation of photosynthetic pigments, the results of this study will provide potential references for the reasonable configuration of freezing and thawing temperatures in the process of storage and transportation of celery products.

A review on mechanisms and impacts of cold plasma treatment as a non-thermal technology on food pigments.

Food characteristics like appearance and color, which are delicate parameters during food processing, are important determinants of product acceptance because of the growing trend toward more diverse and healthier diets worldwide, as well as the increase in population and its effects on food consumption. Cold plasma (CP), as a novel technology, has marked a new trend in agriculture and food processing due to the various advantages of meeting both the physicochemical and nutritional characteristics of food products with minimal changes in physical, chemical, nutritional, and sensorial properties. CP processing has a positive impact on food quality, including the preservation of natural food pigments. This article describes the influence of CP on natural food pigments and color changes in vegetables and fruits. Attributes of natural pigments, such as carotenoids, chlorophyll, anthocyanin, betalain, and myoglobin, are presented. In addition, the characteristics and mechanisms of CP processes were studied, and the effect of CP on mentioned pigments was investigated in recent literature, showing that the use of CP technology led to better preservation of pigments, improving their preservation and extraction yield. While certain modest and undesirable changes in color are documented, overall, the exposure of most food items to CP resulted in minor loss and even beneficial influence on color. More study is needed since not all elements of CP treatment are currently understood. The negative and positive effects of CP on natural food pigments in various products are discussed in this review.

Influence of chitosan-stabilized silver nanoparticles on the physiological and biochemical state of potato plants (<i>Solanum tuberosum</i> L.) <i>in vitro</i> culture

The article contains the results of study of the influence of added to culture medium silver-containing chitosan- based nanocomposites (Chitosan-Ag) at a dilution of 1:500 and 1:1000 (the mass ratio of the components is 50:1 for Chit- Ag 50:1 and 100:1 for Chit-Ag 100:1) on the development of potato microshoots and microclones with a formed root system. Potato microshoots cultivated for 4 weeks on nutrient medium modified with nanocomposites were characterized by slow development and the absence of rhizogenesis, which indicates the toxic effect of the studied nanocomposite concentrations. When replacing the standard nutrient medium with nanocomposites modified for a potato microclone with developed roots, the Chit-Ag 50:1 reduced the rate of growth and development of microclones compared to control and pure chitosan. The Chit- Ag 100:1 nanocomposite had no influence on the microclone growth compared to the control, but reduced the root biomass compared to chitosan. The preservation of photosynthetic pigments and proline concentrations with decreasing the hydrogen peroxide level indicates the absence of the toxic effect of silver-containing chitosan-based nanocomposites on the formed potato microclones. The chitosan concentration increase in the nanocomposite composition helps us to reduce the toxic effect due to the formation of a dense stabilizing shell that delays the silver ion generation.

Use of sedimentary algal pigment analyses to infer past lake-water total phosphorus concentrations

We tested the feasibility of using sedimentary algal pigment analyses by spectral deconvolution to infer past lake-water total phosphorus concentrations. We established equations that link lake-water nutrient concentrations and sediment pigment concentrations, using a combination of calibration in both space and time, with a training set of 31 Swedish lakes. The calibration dataset yielded a significant positive relationship between total carotenoid concentrations and lake-water total phosphorus concentrations. We also compared sediment-pigment-based nutrient inferences with time series of water column monitoring data to evaluate whether temporal changes in total phosphorus concentrations are well captured by analysis of sedimentary pigments. We found that changes in pigment preservation through time can alter the relationship between concentrations of lake-water nutrients and sedimentary pigments, thus limiting the reliability of historical ecological conditions inferred from pigments in the sediment. Our data suggested that ratios of Chlorophyll derivatives to total carotenoids (CD/TC ratio) and Chlorophyll a to Chlorophyll derivatives (CPI) can be used as proxies for pigment preservation. Using our approach, inferred temporal changes in water-column total phosphorus concentrations in lakes are promising, but require further development, specifically with respect to the influence of pigment degradation in both the water column and sediments, as well as the factors that control such degradation.

The Church of S. Maria Delle Palate in Tusa (Messina, Italy): Digitization and Diagnostics for a New Model of Enjoyment

Cultural places represent the tangible part of the identity and historical heritage of a civilization as well as an extraordinary driving force for the economic development of a country. Within its huge asset, Italy counts a wide number of archaeological sites and monuments which, despite their cultural value, are totally cut off from the most important cultural routes. This paper aims to demonstrate how specific actions of digitization can contribute to valorize (restoring a cultural value) ‘marginal’ landmarks, promoting their knowledge and inclusion. The case study described is represented by the Church of “Santa Maria delle Palate”, located inside the well-known Archaeological Park of Halaesa Arconidea (Tusa, ME). The church, built in 1551 and subject to several renovations throughout the centuries, has been investigated as part of an interdisciplinary training and skill transfer project carried out by a CNR-IPCF research team. During the activities, the group of trainees approached a multi-analytic method for the study of many Sicilian places using different techniques such as laser scanning, photogrammetry, thermography and spectroscopy and collecting a large amount of information and data. In 2019, the building in question was the object of a complete architectural survey in order to obtain an accurate digital replica; moreover, the wall painting representing St. Francis, preserved in the southern nave, was investigated through non-invasive investigations (IR-imaging, XRF and Raman spectrometry) with the intention of collecting information about its state of preservation and nature of pigments used and help the restoration work, which would have been carried out in the following months. The result of the work is a combined “digital archive” useful not only for the purposes of conservation, monitoring and dissemination, but as a container of information enjoyable at different levels of depth. In addition to the scientific outcomes achieved for the study of the painting, relevant from the historical and artistic point of view, we must underline the importance of the work for the implementation of a web-based platform where expert and inexpert users can virtually access the church virtual tour and search for specialized contents (e.g., measures, analyzes results). Media such as this are finally demonstrated to be able to promote the inclusion (e.g., for people unable to reach the place or with reducing mobility) and accessibility to cultural places during ordinary (maintenance, closure) or extraordinary events (pandemic).

Effect of Plant Growth-Promoting Bacteria Azospirillum brasilense on the Physiology of Radish (Raphanus sativus L.) under Waterlogging Stress

Stress due to waterlogging is considered an abiotic factor that negatively affects crop production, which, together with the excessive fertilization of crops, reduces cost-effectiveness and generates the need to create sustainable alternatives economically and environmentally. The effect of inoculation with Azospirillum brasilense on the physiology of the Raphanus sativus var. Crimson Giant subjected to waterlogging, was evaluated. Stomatal conductance, chlorophyll concentration and chlorophyll a fluorescence were analyzed to establish this effect, corroborating the beneficial effect of inoculation with A. brasilense in radish under waterlogging stress. The stomatal conductance of inoculated and waterlogged treatments presented the same values as the control plants, and photosystem II efficiency was favored in inoculated and waterlogged treatments (0.6 Fv/Fm) compared to non-inoculated and waterlogged treatments (0.3 Fv/Fm). The results suggested that this increased efficiency was due to the preservation of photosynthetic pigments in the tissues, allowing the preservation of stomatal conductance and a reduction in the amount of energy dissipated in the form of heat (fluorescence) due to inoculation with A. brasilense. Therefore, plant growth-promoting bacteria are responsible for activating and improving some physiological mechanisms of the plant.

Pigmented Remedies: The Pharmacy of Colour in Early Modern Europe.

This article will examine pigments recently identified in an unpublished conservation survey at the Wellcome Collection that included two 17th-century medical manuscripts. These pigments, which were drawn from plant and mineral products, served a dual purpose based on their medicinal and pigmented properties. An exploration of how these pigments were used (and why) by a range of practitioners - including apothecaries, physicians, "kitchen physicians," and artisans - reveals the importance of colour throughout early modern Europe. The persistence of traditional medical theories is revealed by examining evidence across an extensive period covering the 16th to the 18th century. Receipt books, medical treatises, and health guides are contrasted with artisanal texts reflecting the blurring of boundaries between the worlds of medicine and art. Modern analysis by conservators of colour used in medieval and early modern texts is crucial to the preservation of pigments but also provides a deeper understanding of what and how pigmented products were used in the period and, ultimately, informs our current understandings of early modern life and medicine.

Effect of nonthermal treatments on selected natural food pigments and color changes in plant material.

In recent years, traditional high-temperature food processing is continuously being replaced by nonthermal processes. Nonthermal processes have a positive effect on food quality, including color and maintaining natural food pigments. Thus, this article describes the influence of nonthermal, new, and traditional treatments on natural food pigments and color changes in plant materials. Characteristics of natural pigments, such as anthocyanins, betalains, carotenoids, chlorophylls, and so forth available in the plant tissue, are shortly presented. Also, the characteristics and mechanism of nonthermal processes such as pulsed electric field, ultrasound, high hydrostatic pressure, pulsed light, cold plasma, supercritical fluid extraction, and lactic acid fermentation are described. Furthermore, the disadvantages of these processes are mentioned. Each treatment is evaluated in terms of its effects on all types of natural food pigments, and the possible applications are discussed. Analysis of the latest literature showed that the use of nonthermal technologies resulted in better preservation of pigments contained in the plant tissue and improved yield of extraction. However, it is important to select the appropriate processing parameters and to optimize this process in relation to a specific type of raw material.

Algal Community Change in Mountain Lakes of the Alps Reveals Effects of Climate Warming and Shifting Treelines1.

The biological communities of mountain lakes are suspected to be highly sensitive to global warming and associated catchment changes. To identify the parameters determining algal community responses, subfossil pigments from 21 different mountain lakes in the Bavarian-Tyrolean Limestone Alps were investigated. Sediment cores were radio-isotopically dated, and their pigment preservation evaluated. General additive models (GAM) of pigment compositions were calculated with temperature as the explanatory variable and generalized linear models with several lake parameters explaining log-transformed GAM P-values. Lake depth and trophic state were identified as major control variables of the algal community and productivity changes. Shifts in a deep oligotrophic alpine lake (lg(P)=-1.04) were half as strong as in a shallow mesotrophic alpine lake (lg(P)=-1.86) with faster warming and higher productivity forcing the development of biomass. Phytoplankton and macrophyte pigments increased clearly with warming, at lower altitudes, and decreased at the treeline, so that periphytic pigments dominated alpine sediments. This pattern is probably the result of interactions of UV radiation and allochthonous inputs of DOM. Our findings suggest that (sub)alpine shallow lakes with higher nutrient levels are most vulnerable to climate change-driven changes whereas deep, nutrient-poor lakes appear more resilient.

Quantification of chlorophyll a, chlorophyll b and pheopigments a in lake sediments through deconvolution of bulk UV–VIS absorption spectra

Assessments of aquatic paleoproduction and pigment preservation require accurate identification and quantification of sedimentary chlorophylls. Using chromatographic techniques to analyze long records at high resolution is impractical because they are expensive and labor intensive. We have developed a new rapid and low-cost approach to infer the concentrations of chlorophyll a, chlorophyll b and related chlorophyll derivatives (pheopigments a) from the mathematical decomposition of UV–VIS measured bulk spectrophotometer absorption spectra of standard solutions and sediment extracts. We validated our method against high-performance liquid chromatography (HPLC) measurements on standard solutions and on varved, anoxic sediment from eutrophic Lake Lugano (Ponte Tresa sub-basin, southern Switzerland), where the history of productivity is relatively well known for the twentieth century. Our mathematical approach quantifies the concentration of chlorophyll b ( $$ {\text{R}}_{{{\text{ad}}_{\text{J}}}}^{2} $$ = 0.99, RMSEP ~ 5.9%), chlorophyll a ( $$ {\text{R}}_{{{\text{ad}}_{\text{J}}}}^{2} $$ = 0.98, RMSEP ~ 5.0%), and pyropheophorbide a ( $$ {\text{R}}_{{{\text{ad}}_{\text{J}}}}^{2} $$ = 0.99, RMSEP ~ 7.8%) in standard solutions. We obtain comparable results for total chloropigment a (chlorophyll a + pheopigments a), chlorophyll a and diagenetic products (pheopigments a) in the sediment samples of our case study (Ponte Tresa). Here, HPLC concentrations of chlorophyll b are very low. The method has, however, the potential to achieve values for chlorophyll b concentrations in sediments with chlorophylls a/chlorophylls b ratios lower than 3.4. The pigment stratigraphy of the Ponte Tresa sediments correspond very well with the paleoproduction and eutrophication history of the twentieth century. The ratio between chlorophyll a and pheopigments a used as a qualitative indicator of sedimentary chlorophyll preservation (chlorophyll a/{chlorophyll a + pheopigments a}) is only weakly correlated with aquatic paleoproduction (radj = 0.35, p-value = 0.045) and remained remarkably constant in the recent century despite strong anthropogenic eutrophication. The new method is useful for obtaining, in a cost- and time-efficient way, information about major sedimentary pigment groups that are relevant to inferring paleoproduction, potentially green algae biomass, pigment preservation and early diagenetic effects.

Surface mineral crusts: a potential strategy for sampling for evidence of life on Mars

AbstractSurface mineral crusts on Earth are highly diverse and usually, contain microbial life. Crusts constitute an attractive target to search for life: they require water for their formation, they efficiently entrap organic matter and are relatively easy to sample and process. They hold a record of life in the form of microbial remains, biomolecules and carbon isotope composition. A miniaturized Raman spectrometer is included in the ExoMars 2020 payload as it is sensitive to a range of photosynthetic pigments. Samples from the Haughton Impact Structure, Canadian High Arctic and others, shows the preservation of pigments in a range of crust types, especially supra-permafrost carbonate crusts and cryptogamic crusts. The Raman spectral signatures of these crusts are shown along with biomarker analysis to showcase these techniques prior to the ExoMars 2020 mission. Carotenoids and other photoprotective microbial pigments are identified in the Haughton surface crusts using Raman spectroscopy. Gas chromatography-mass spectrometry analyses show a distribution of fatty acids which are most likely from a cyanobacterial source. The successful demonstration of these analyses in the Haughton Impact structure shows the biosignature of surface mineral crusts can be easily extracted and provides an excellent target for sampling evidence of life on Mars.

Algal pigments in Hornsund (Svalbard) sediments as biomarkers of Arctic productivity and environmental conditions

AbstractPigments (chloropigments-a and carotenoids) in sediments and macroalgae samples, collected in Hornsund, in July 2015 and July 2016, were analysed (HPLC) in this work. In spite of the aerobic conditions and the periodic intensive solar irradiation in the Arctic environment, neither of which favour pigment preservation in water column and surface sediments, our results indicate that these compounds can provide information about phytoplankton composition, primary production and environmental conditions in this region. The sum of chloropigments-a, a marker of primary production, in the Hornsund sediments varied from 0.40 to 14.97 nmol/g d.w., while the sum of carotenoids ranged from 0.58 to 8.08 nmol/g d.w. Pheophorbides-a and pyropheophorbides-a made up the highest percentage in the sum of chloropigments-a in these sediments, supplying evidence for intensive zooplankton and/or zoobenthos grazing. Among the carotenoids, fucoxanthin and its derivatives (19’-hexanoyloxyfucoxanthin and 19’-hexanoyloxy-4-ketofucoxanthin) contributed the highest percentage, which points to the occurrence mainly of diatoms and/or haptophytes in the water. The pigment markers show that the input of macroalgae to the total biomass could be considerable only in the intertidal zone.

Melatonin Application to Pisum sativum L. Seeds Positively Influences the Function of the Photosynthetic Apparatus in Growing Seedlings during Paraquat-Induced Oxidative Stress.

Melatonin, due to its pleiotropic effects plays an important role improving tolerance to stresses. Plants increase endogenous melatonin synthesis when faced with harsh environments as well as exogenously applied melatonin limits stress injuries. Presented work demonstrated that single melatonin application into the seeds during pre-sowing priming improved oxidative stress tolerance of growing seedlings exposed to paraquat (PQ). PQ is a powerful herbicide which blocks the process of photosynthesis under light conditions due to free radicals excess production, when O2 is rapidly converted to and subsequently to other reactive oxygen species. The parameters of chlorophyll fluorescence [Fv/Fm, Fv/Fo, Rfd, ΦPSII, qP, and non-photochemical quenching (NPQ)] in all variants of pea leaves (derived from control non-treated seeds – C, and those hydroprimed with water – H, and hydroprimed with melatonin water solution 50 or 200 μM – H-MEL50 and H-MEL200, respectively) were analyzed as a tool for photosynthetic efficacy testing. Moreover stability of the photosynthetic pigments (chlorophylls a, b, and carotenoids) was also monitored under oxidative stress conditions. The results suggest that melatonin applied into the seed significantly enhances oxidative stress tolerance in growing seedlings. This beneficial effect was reflected in reduced accumulation of in leaf tissues, preservation of photosynthetic pigments, improved functioning of the photosynthetic apparatus and higher water content in the tissues during PQ-mediated stress. Our findings provide evidence for the physiological role of this molecule and serve as a platform for its possible applications in agricultural or related areas of research.

Long-term changes in pigmentation of arctic Daphnia provide potential for reconstructing aquatic UV exposure

Despite the biologically damaging impacts of solar ultraviolet radiation (UV) in nature, little is known about its natural variability, forcing mechanisms, and long-term effects on ecosystems and organisms. Arctic zooplankton, for example the aquatic keystone genus Daphnia (Crustacea, Cladocera) responds to biologically damaging UV by utilizing photoprotective strategies, including pigmentation. We examined the preservation and content of UV-screening pigments in fossil Daphnia remains (ephippia) in two arctic lake sediment cores from Cornwallis Island (Lake R1), Canada, and Spitsbergen (Lake Fugledammen), Svalbard. The aims were to document changes in the degree of UV-protective pigmentation throughout the past centuries, elucidate the adaptive responses of zooplankton to long-term variations in UV exposure, and estimate the potential of fossil zooplankton pigments in reconstructing aquatic UV regimes. The spectroscopic absorbance measurements of fossil Daphnia ephippia under UV (280–400 nm) and visible light (400–700 nm) spectral ranges indicated that melanin (absorbance maxima at UV wavebands 280–350 nm) and carotenoids (absorbance maxima at 400–450 nm) pigments were preserved in the ephippia in both sediment cores. Downcore measurements of the most important UV-protective pigment melanin (absorbance measured at 305 and 340 nm) showed marked long-term variations in the degree of melanisation. These variations likely represented long-term trends in aquatic UV exposure and were positively related with solar radiation intensity. The corresponding trends in melanisation and solar activity were disrupted at the turn of the 20th century in R1, but remained as strong in Fugledammen. The reversed trends in the R1 core were simultaneous with a significant aquatic community reorganization taking place in the lake, suggesting that recent environmental changes, likely related to climate warming had a local effect on pigmentation strategies. This time horizon is also concurrent with previously recorded major ecological shifts in circumpolar lakes when human induced changes in ecological processes of sensitive arctic ecosystems started to occur. The current centennial record of UV-induced melanisation of sedimentary Daphnia ephippia presents unique reference material for assessing UV impacts in arctic aquatic ecosystems before human influence and during the 20th century climate change and provides potential for assessing past aquatic UV regimes.

Changes in photosynthesis of alpine plant Saussurea superba during leaf expansion

The native alpine plant Saussurea superba is widely distributed in Qinghai–Tibetan Plateau regions. The leaves of S. superba grow in whorled rosettes, and are horizontally oriented to maximize sunlight exposure. Experiments were conducted in an alpine Kobresia humilis meadow near Haibei Alpine Meadow Ecosystem Research Station (37°29′–37°45′N, 101°12′–101°33′E; alt. 3200 m). Leaf growth, photosynthetic pigments and chlorophyll fluorescence parameters were measured in expanding leaves of S. superba. The results indicate that leaf area increased progressively from inner younger leaves to outside fully expanded ones, and then slightly decreased in nearly senescent leaves, due to early unfavorable environmental conditions, deviating from the ordinary growth pattern. The specific leaf area decreased before leaves were fully expanded, and the leaf thickness was largest in mature leaves. There were no significant changes in the content of chlorophylls (Chl) and carotenoids (Car), but the ratios of Chl a/b and Car/Chl declined after full expansion of the leaves. The variation of Chl a/b coincided well with changes in photochemical quenching (qP) and the fraction of open PSII reaction centers (qL). The maximum quantum efficiency of PSII photochemistry after 5 min dark relaxation (F(v)/F(m)) continuously increased from younger leaves to fully mature leaves, suggesting that mature leaves could recover more quickly from photoinhibition than younger leaves. The light-harvesting capacity was relatively steady during leaf expansion, as indicated by the maximum quantum efficiency of open PSII centers (\(F_{\text{v}}^{{\prime }}\)/\(F_{\text{m}}^{{\prime }}\)). UV-absorbing compounds could effectively screen harmful solar radiation, and are a main protection way on the photosynthetic apparatus. The decline of qP and qL during maturation, together with limitation of quantum efficiency of PSII reaction centers (L(PFD)), shows a decrease of oxidation state of QA in PSII reaction centers under natural sunlight. Furthermore, light-induced (ΦNPQ) and non-light-induced quenching (ΦNO) were consistent with variation of L(PFD). It is concluded that the leaves of S. superba could be classified into four functional groups: young, fully expanded, mature, and senescent. Quick recovery from photoinhibition was correlated with protection by screening pigments, and high level of light energy trapping was correlated with preservation of photosynthetic pigments. Increasing of ΦNPQ and ΦNO during leaves maturation indicates that both thermal dissipation of excessive excitation energy in safety and potential threat to photosynthetic apparatus were strengthened due to the declination of qP and qL, and enhancement of L(PFD).

EFFECT OF DRYING METHODS ON CONTENT OF SOME NATURAL PIGMENTS IN URTICA DIOICA L. AND MELISSA OFFICINALIS L.

Medicinal plants are usually marketed to the public in a dried form and in this form they can also be used for the needs of the pharmaceutical industry. Since the drying process can affect chemical changes in the plants several drying methods and conditions have been tested to preserve the quality and quantity of biologically active components. The objective of this study was to investigate the effect of convection oven drying at 25°C ± 1°C for 65 hours, microwave oven drying at 800 W for 45 seconds, and air drying with sun exposure at 25°C ± 1°C for 65 hours on the content of chlorophylls and carotenoids in leaves of two medicinal plants. The plants selected were stinging nettle (Urtica dioica L.) and lemon balm (Melissa officinalis L.). The content of the natural pigments was investigated in the prepared extracts by the UV-VIS spectrophotometric method. Results showed higher content of pigments in Melissa officinalis when microwave drying procedure was applied compared to the oven dried samples and the sun dried samples (air dried with sun exposure) but a significant difference was only observed in the content of chlorophyll b. In Urtica dioica the air drying technique with sun exposure can be considered to be a more suitable drying procedure which preserves a higher amount of all pigments. Sun dried Urtica dioica samples had significantly higher chlorophylls and carotenoids content compared to the oven dried and microwave dried samples. In general, air drying with sun exposure seems to be the most suitable drying method in terms of preservation of pigments under study. This technique represents the simplest and most energy efficient drying procedure.

Painted Gallo-Roman Figurines in Vendeuil-Caply

In 2013, an archaelogical team exploring the site of Vendeuil-Caply in northern France brought to light a new corpus of Gallo-Roman terracotta figurines. The particular importance of this corpus lies in the preservation of pigments that decorated the surface of these figurines. From the 19th century onwards, the generic term that has been used to refer to this kind of Gallo-Roman production has been “white-clay,” most often associated with the Allier region of central France. This term arose from the stark, white color of the fabric. Consequently, archaeologists were quite surprised to find not only color on the figurines, but also repetitive patterns, such as feathers, or details of clothing.

Agro-food industry byproducts into value-added extruded foods

Food industry co-products, fruit pomace and liquid whey, were converted into shelf-stable, puffed products by using low-shear, low-temperature supercritical fluid extrusion. Co-products were utilized as a source of dietary fiber, phytochemicals, and milk nutrients in extruded products. Liquid whey was concentrated and pumped directly into extruder barrel in lieu of water while processing cereal formulations fortified with finely ground fruit pomace. The resulting extruded products were very light in weight with 0.21–0.35g/cm3 density and contain14g dietary fiber, 93mg gallic acid equivalent polyphenols, and 652mg vitamin C equivalent antioxidants in 100g products. The natural fruit color is retained in the final product, indicating the preservation of color pigments and the associated bioactive compounds. About 84% of the total phenolics and 74% of the antioxidants of apple pomace were preserved in the final extrudates. The utilization of the agro-industry waste streams offers effective preservation and utilization of the nutritionally attractive byproducts as a source of functional ingredients in extruded products while adding value to the industrial waste streams.

Color and Bioactive Compounds Characteristics on Dehydrated Sweet Cherry Products

It is widely known that quality properties of fruits can be affected by drying processes. The approach was the quality improvement of dried cherry products through the application of combined technologies of drying and pretreatments. The objective of this work was to analyze the effect of blanching or sugar infusion prior to air-drying or freeze-drying on quality properties such as color, bioactive compounds, and antiradical power of two cherry products (discs and dices). Air-drying caused darkening, whereas freeze-drying provoked higher lightness of discs compared to fresh fruit (p < 0.05). Cherry dices were lighter than the fresh fruit. A high retention of total anthocyanin (ACY) and phenolic content (TPC) was obtained in blanched freeze-dried discs (ACY = 165 ± 22 mg Cyd-3-glu/100 g d.w.; TPC = 739 ± 55 mg GAE/100 g d.w.). Sugar infusion pretreatment caused an important decrease in ACY (31–89 mg Cyd-3-glu/100 g d.w.) and TPC (222–271 mg GAE/100 g d.w.). When blanching was applied prior to air-drying, samples presented the highest antiradical power, similar to that observed in fresh fruit. In dices, the best quality attributes in terms of superficial color were found in control freeze-dried samples since they presented minor shifts in hue angle and a greater preservation of anthocyanin pigments (ACY = 211 ± 30 mg Cyd-3-glu/100 g d.w.). However, control air-dried dices presented the highest phenolic content (TPC = 771 ± 65 mg GAE/100 g d.w.). Regarding the possible application of the dry cherry products, discs could be directly consumed as snacks, while dices could be incorporated as ingredients in fruit bars, cookies, or muffins.