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Apple (Malus domestica) fruits accumulate negligible levels of carotenoids, antioxidant pigments that are precursors for vitamin A in humans. As vitamin A deficiency is an important public health issue, we aimed at increasing carotenoids in apple by constitutively expressing the Arabidopsis thaliana DXR gene, one of the key regulatory steps in the plastidial isoprenoid pathway. For this purpose, we optimized an Agrobacterium-mediated transformation method in the commercial Fuji Raku Raku variety. This resulted in a shoot establishment efficiency of 0.75% at 20 weeks after infection. Molecular and microscopical analyses revealed that 80% of the hygromycin resistant shoots contained and expressed AtDXR:eGFP and that the AtDXR:eGFP fusion protein located in plastids. Transgenic seedlings displayed up to 3-fold increase in total carotenoids and in individual carotenoids compared to the WT, correlating with an increased transcript abundance of endogenous carotenogenic genes such as MdDXS, MdPSY1, MdPSY2, MdPSY3, MdLCYB1, and MdLCYB2. In addition, buds of 2-year-old transgenic dormant trees showed an increment up to 3-fold in lutein, and transient transformation of fruits revealed that AtDXR induced a 2-fold increment in total carotenoids. Thus, these results suggest that DXR may be a good candidate for increasing carotenoid levels in apple fruits through metabolic engineering., (© 2020 Wiley Periodicals, Inc.)

In Chlamydomonas reinhardtii, ketocarotenoid biosynthesis is limited to the diploid zygospore stage. In this study, we attempted to engineer the ketocarotenoid pathway into Chlamydomonas haploid vegetative green cells by overexpressing the key enzyme ß-carotene ketolase (CrBKT). We chose strain CC-4102 for the approach; competitive pathways, α-carotene biosynthesis and xanthophyll cycle are silenced in this strain. Driven by the strong constitutive HSP70/RBCS2 promoter CrBKT overexpression resulted in the production of canthaxanthin, the ketolation product from ß-carotene as well as a drastic reduction in the chlorophyll concentration. Intriguingly, these phenotypes could only be detected from lines transformed and grown heterotrophically in the dark. Once exposed to light, these transformants lost the aforementioned phenotypes as well as their antibiotic resistance. This phenomenon is in agreement with the fact that we were unable to recover any canthaxanthin-producing line among light-selected transformants.

Introduction: The castor bean (Ricinus communis L.), is an oilseed of relevant economic and social importance. From its seeds is extracted an oil of excellent properties, having wide use as industrial input and several applications. It is cultivated since the times of the ancient civilizations, the castor bean is a rustic plant, resistant to drought, belonging to the family of Euphorbiaceae, Drought stress, in addition to the negative effect on yield, causes or exacerbates other stresses, especially the stress of nutrient deficiencies for the plant. The purpose of this investigation was to study the effect of irrigation levels and Superabsorbents and biofertilizers on the agronomic properties of castor oil. Materials and methods: This experiment was conducted in West Azarbaijan Agricultural Research and Education Center, Orumieh-Iran in 2018-2021 crop season. A field experiment was carried out by a split-plot design based on a completely randomized block design with three replications. The first factor included Four levels (70, 100, 130, and 160 mm of evaporation pan), in the main plot and Sub-factor includes application of biofertilizer combination in four levels (Azospirillium, Citrobacter, combination of application of Azospirillium in Citrobacter and control without fertilizer) and superabsorbent in two levels (superabsorbent consumption and non-superabsorbent consumption) as factorial were placed in subplots. In this study, Chlorophyll a, Chlorophyll b, Cartonoid, Soluble sugar, prolin content, Catalase, Malondialdehyde, and protein content were measured. Also Traits were analyzed by using SAS 9.2 software and means comparison was tested by least significant difference (LSD). Results and discussion: Based on the results of the combined analysis of the variance of the data, there was a significant difference in was observed between the two years in terms of malondialdehyde content. There was a significant difference between the irrigation levels in terms of the effect on all traits of the probability level of 1%. The interaction effect of year and irrigation was significant only on leaf proline content at the level of 1% probability. There was a significant difference between the biofertilizer treatments and the interaction effect of biofertilizer on irrigation and superabsorbent levels in terms of the effect on all traits at the level of one percent probability. The interaction effect of irrigation with superabsorbent on chlorophyll a and b content and soluble sugar content at 1% probability level and on proline content and protein percentage at 5% probability level was significant. Between treatments of biofertilizer with superadd interaction in terms of the effect on chlorophyll b content, soluble sugar, proline content, malondialdehyde content, and protein percentage at the level of 1% percent and in terms of the effect on chlorophyll content, carotenoids and catalase activity in 5% probability level There was a significant difference. The results showed the highest chlorophyll a (23.00 mg g-1) and b content (14.93 mg g-1) as well as carotenoids (30.39 mg g-1) and the lowest amount of soluble sugar (113.33 micromol g-1 fresh weight), catalase (32.97ΔA240 mg-1 protein), malondialdehyde (132.44 nmol g-1 FW) and protein percentage (4.69%) were assigned to with Citrobacter treatment and irrigation after 70 mm of evaporation. Also, the highest soluble sugar content (131.42 micromol g-1 FW), proline (65.91 micromol g-1 FW), protein (11.48 %) was assigned to the treatment with Azosprilium + Citrobacter and irrigation after 160 mm of evaporation. In this study, the use of superabsorbent in the irrigation treatment of 70 mm evaporation had the highest chlorophyll a (21.29 mg g-1) and b content (12.78 mg g-1) and the lowest amount of soluble sugar (112.50 micromol g-1 FW), proline (26.50 micromol g-1 FW), catalase (35.99 ΔA mg-1 protein) and protein percentage (5.00%), While the highest soluble sugars content (129.12 micromols g-1 FW), proline (58.70 micromols g-1 FW), malondialdehyde (159.71 nmol g-1 FW), and protein (10.37 %), was observed in the treatment of superabsorbent application along with irrigation after 160 mm. In this study, the simultaneous application of superabsorbent and inoculation with azospirlium showed the highest chlorophyll a (22.25 mg g-1), b content (13.79 mg g-1), carotenoid (29.02 mg g-1), protein (7.99%) and the lowest content of catalase enzyme (39.58 ΔA240 mg-1 protein), The highest soluble sugar content (122.88 micromol g-1 FW) and the lowest amount of malondialdehyde (141.82 nmol g-1 FW) were detected in the treatment of superabsorbent application with Citrobacter. Conclusion: In this study, water deficit had an adverse effect on the physiological properties of castor oil. However, the use of biofertilizers and superplasticizers by improving biochemical and antioxidant properties was able to moderate the effect of drought stress on physiological properties and stabilize photosynthetic pigments, and the stability of photosynthetic pigments can improve photosynthetic properties and plant growth under water deficit conditions. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate three species of Dunaliella microalgae (Dunaliella salina, Dunaliella viridis, and Dunaliella sp.) indigenous to Iran as new sources of natural chemical and bioactive compounds for exploring pharmaceutical and nutraceutical potential applications. The results showed that the fat, carbohydrate (mono‐ and di‐saccharide), dietary fiber, and protein content of Dunaliella were in the range of 13.19–25.02, 7.59–12.37, 42.10–48.82, and 17.68–22.50 (%), respectively. Dunaliella salina contained a pigment fraction of 11.50%, which was largely composed of carotenoid (7.41%) and chlorophyll (4.09%). Antioxidant capacity and inhibition of 2,2‐diphenyl‐1‐1‐picrylhydrazyl (DPPH) of Dunaliella salina were 34.54 mg/1000 g and 55.63%, respectively. The lipid profile also revealed that three isolated Dunaliella are remarkable sources of polyunsaturated fatty acids (25.42%–40.13%). Further, the ratios of ∑n‐3/∑n‐6 (2.79%), docosahexaenoic acid (6.15%), and eicosapentaenoic acid (11.26%) were the highest in Dunaliella salina. The results, thus, proved that Dunaliella spp., especially Dunaliella salina (IBRC‐M 50030), which originates from a lake in Semnan province, Iran, has potential applications in the food and pharmaceutical industries due to its appropriate biopigment, protein, lipid, antioxidant activity, long‐chain polyunsaturated fatty acids, docosahexaenoic acid, and eicosapentaenoic acid. [ABSTRACT FROM AUTHOR]

Nowadays, the nutritional value of cookies is relatively low. To reduce wheat flour usage in the cookies, the freeze-dried whole leaf (WL) and chloroplast-rich fraction (CRF) derived from Thai jasmine rice grass were used as a food ingredient to increase the nutrients of cookies. Chloroplast is a rich source of macro and micronutrients. Thus, the use of chloroplast might improve the nutrients in food products. This research aimed to study the physical and chemical characteristics of freeze-dried WL and CRF from Thai jasmine rice grass. The nutritional and physical properties of the butter cookies substituted wheat flour with WL or CRF (0%, 2%, and 4% (w/w)) were also investigated. The result showed that CRF derived from Thai jasmine rice grass contained a significantly larger amount of macro and micronutrients (protein, lipid, ash, β-carotene, and total carotenoids) compared with WL (P<0.05), except for carbohydrate, fiber, total chlorophyll, and total phenolic compound. Furthermore, the cookies replaced wheat flour with 4% WL from Thai jasmine rice grass, containing the highest fiber led to a decreased spread ratio and increased the hardness of cookies. Whilst the cookies substituted with 4% CRF (w/w) were similar in texture to the cookies containing only wheat flour (P>0.05). Moreover, the replacement of wheat flour with freeze-dried WL and CRF derived from Thai jasmine rice grass enhanced nutrients and antioxidant activity compared with cookies in the absence of WL and CRF. The butter cookies with 4% replacement of WL showed the highest level of chlorophyll and total phenolic; the cookies with 4% replacement of CRF contained the largest amount of β-carotene (provitamin A) and total carotenoids. However, both cookies containing either WL or CRF were not significantly different in antioxidant activity (P>0.05). [ABSTRACT FROM AUTHOR]

A 50-year-old solitary, sun-exposed ginkgo tree had strongly been pruned in the fall of 2021. Very few buds for the formation of new leaves, twigs, and branches were left over. In spring 2022, these few remaining buds responded with the formation of a different leaf type. These leaves were 2.7 times larger and also thicker than in the years before. In addition, the mean content of total chlorophylls [Chl (a+b)] per leaf area unit of dark-green leaves was 1.45, those of green leaves two times higher as compared to the years before pruning and the two other ginkgo trees which had been investigated in parallel. A comparable increase was also found for the level of total carotenoids (x+c). The mean content for Chl (a+b) were 1,118 mg m-2 for dark-green and 898 mg m-2 for green leaves as compared to 435 to 770 mg m-2 in leaves of other trees. The higher values for Chl (a+b) and total carotenoid content showed up also on a fresh and dry mass basis. Thus, with the formation of a new, larger leaf type by changes in morphology (leaf size and thickness) and the increase of photosynthetic pigments, the pruned ginkgo tree was able to compensate for the much lower number of leaves and photosynthetic units. [ABSTRACT FROM AUTHOR]

In the present study, the effects of cadmium (25 µM and 50 µM) and zinc (200 µM and 400 µM) treatments on some bioactive compounds and mineral levels in leaves of japanese barberry, boxwood, and gold tassel genotypes were investigated. Given the results, it was determined that photosynthetic pigments were stimulated by 200 µM Zn and 400 µM Zn. Boxwood was found to be tolerant to the treatments in terms of chlorophyll and carotenoid. In contrast, japanese barberry was found to be tolerant in terms of chlorophyll b and total chlorophyll. The amount of anthocyanin was higher in the leaves of gold tassel, and boxwood and the total phenolic was higher level in gold tassel and japanese barberry in all treatments. Proline and nitrate levels were generally high in the treated groups of three plants, as well as RWC in japanese barberry and boxwood. Given the element results, japanese barberry had a higher accumulation capacity for P, S, Mn, Cl, Cd, Fe, Al, Si, Cu, Ba, Zn, Ti, and Cr, boxwood for K, Mn, Cl, Cd, Zn, Fe, Al, Si, and Cr, and Gold tassel for K, P, S, Mn, Cl, and Cd. As a result, boxwood showed a higher tolerance to 400 µM Zn, japanese barberry plant to 200 µM Zn, and 50 µM Cd. It can be said that boxwood and japanese barberry plants can be used in afforestation projects in urban parks, gardens, and roadside, as well as in areas with high soil pollution, to reduce the pollution damage. [ABSTRACT FROM AUTHOR]

Drought stress has become more common in recent years as a result of climate change impacts on the production of banana crops and other fruit trees. The growth and productivity of Musa spp are severely impacted by the gradual degradation of water resources and the erratic distribution pattern of annual precipitation amount. The aim of the work includes increased drought tolerance in light of water scarcity in the world as a result of the bananas’ being gluttonous for water needs. This investigation was carried out from 2019 to 2020 to study the effect of potassium silicate on morphological growth and biochemical parameters of Musa acuminata L under drought stress by PEG. As a result, drought stress reduced the morphological characteristics such as shoots number, shoot length, roots number, and survival percentage and biochemical characteristics such as chlorophyll a, b, carotenoids, stomatal status, and RWC. While proline content increased in the leaf of M. acuminata L. Media complemented with K2SiO3 (2 to 6 mM) either individually or in combination with PEG led to an improvement in all morphological and biochemical characteristics. The activities of CAT, POD, and PPO enzymes increased significantly compared to control. Furthermore, the lowest PPO, CAT, and POD activity were achieved. Additionally, K2SiO3 treatments under drought stress successfully enhanced the leaf stomatal behavior. Our results suggest that K2SiO3 can help to maintain plant integrity in the tested cultivar under drought stress. [ABSTRACT FROM AUTHOR]

Bitter gourd (Brâncuși cultivar) stems, tendrils and leaves from local production were studied for their content in some classes of nutritive compounds. Chlorophyll, carotenoids (total, βcarotene and lycopene), phenolic compounds (total, flavonoids, anthocyanins, tannins) and ascorbic acid were determined. Vegetative organs of M. charantia were found to contain high amounts of chlorophyll (1,643 mg/kg DW in leaves). The total carotenoid content was 176-386, with the highest amounts in leaves. While β-carotene was dominant in the stems (177 mg/kg), the other vegetative organs had significant amounts of lycopene (67 mg/kg in leaves). The total phenolic inventory ranged from 6,283 in leaves to 9,657 in stems. Flavonoids were dominant, by 50-70%, with the highest amounts in stems. Of these, 501-997 mg/kg were anthocyanins. Tannins constituted 8.1-9.3% of the phenolic inventory. Ascorbic acid concentration ranged between 1,7134 and 2,691 mg/kg, with the highest values in tendrils. In conclusion, vegetative organs of M. charantia can be a valuable source of phytochemicals. [ABSTRACT FROM AUTHOR]

Caraway leaves from local production were studied for their content in some classes of compounds with antioxidant potential. Chlorophylls, carotenoids (total, β-carotene, lycopene, lutein, zeaxanthin and cryptoxanthin), phenolic compounds (total, flavonoids, anthocyanins), ascorbic acid, essential oils. The chlorophyll content was 346 mg/kg DW, of which only chlorophyll a was found in detectable amounts. Total carotenoid concentration was 2,190 mg/kg DW, consisting almost entirely (2,078 mg/kg) of β-carotene including, 86 mg/kg lutein and low amounts of other compounds. 23,755 mg/kg was the total phenolic content, of which 6,435 mg/kg flavonoids, including 104 mg/kg anthocyanins. Leaves contained 2,319 mg/kg ascorbic acid and 6,676 mg/kg essential oil. These concentrations are comparable with those commonly found in most studied species of Apiaceae [ABSTRACT FROM AUTHOR]

Bitter gourd fruits (Brâncuși cultivar) from local production were studied for their content in some classes of nutritive compounds. Carotenoids (total, β-carotene, lycopene and lutein), phenolic compounds (total, flavonoids, anthocyanins, tannins), ascorbic acid, soluble sugars and lipids were determined. With 231/251 mg/kg DW (peel/pulp) total carotenoid content in M. charantia fruits was lower than in other known Cucurbitaceae. β-carotene was dominant in the peel while lycopene constituted a large fraction in the pulp. Lutein was found in low amounts (<1 mg/kg) only in the peel. On the contrary, with 13,527/18,598 mg/kg, the total phenolic inventory is richer than in many other related species. Flavonoids (8,763/14,545 mg/kg) were dominant in both peel and pulp. Of these, only a small fraction (267/212 mg/kg) were anthocyanins. Tannins constituted over 9.5% of the phenolic inventory. Ascorbic acid concentration was high, 14,689 mg/kg in peel and 12,847 mg/kg in pulp. Soluble sugars were 9,035/9,579 while lipids were 3,800/3,200 mg/kg. [ABSTRACT FROM AUTHOR]

Fennel leaves from local production were studied for their content in some classes of compounds with antioxidant potential. Chlorophylls (a and b), carotenoids (total, β-carotene, lycopene, lutein, zeaxanthin and cryptoxanthin), phenolic compounds (total, flavonoids, anthocyanins), ascorbic acid, essential oils. The chlorophyll content was 1,459 mg/kg DW, of which over 86% chlorophyll a. Total carotenoid concentration was 1,609 mg/kg DW, including 1,002 mg/kg β-carotene, 109 mg/kg lycopene, 32 mg/kg lutein and low amounts of other compounds. 13,292 mg/kg was the total phenolic content, of which 686 mg/kg flavonoids, including 146 mg/kg anthocyanins. Leaves contained 2,658 mg/kg ascorbic acid and 20,553 mg/kg essential oil. While comparable with other Apiaceae in most types of compounds, fennel had a lower flavonoid inventory, but a higher amount of lycopene. [ABSTRACT FROM AUTHOR]

The aim of the study was to measure the tensile strength of 4-year-old alfalfa leaves cultivated from seeds exposed to pre-sowing stimulation with He–Ne laser light for 1 or 5 min (designated respectively as F1 and F5) and alternating magnetic field with the exposure time of 1 or 5 min (respectively, L1 and L5). The leaves were measured in terms of blade length and width as well as petiole thickness prior to the tensile test. Measurements were also conducted to determine the chlorophyll fluorescence lifetime and content of photosynthetic pigments (chlorophyll a, b, a + b and carotenoids). The observed tensile strength was between 1.59 and 2.45 N. In the test group, the observed strength was lower in leaves collected from the top and central section of the stem but higher in the bottom part of the stem as compared to the control. The maximum increase of the tearing tensile force relative to the control (C) was observed for the L1 and F1 stimulation samples in leaves collected from the top and bottom parts of the stem, while the maximum decrease for that force was recorded for L5 leaves from the middle and top part of the stem. Chlorophyll fluorescence lifetimes and the overall content of photosynthetic pigments (chlorophyll a and b and carotenoids) were noticeably decreased in the leaves subjected to the stressors/stimulants applied. The results obtained for F1, L5 and, L1 stimulation revealed a decrease in fluorescence lifetimes. The content of photosynthetic pigments was also decreased under the influence of laser light stimulation (L1). This was a clear indication of plant ageing. [ABSTRACT FROM AUTHOR]

A fast and low-cost analytical method to determine the concentrations of carotenoids (β-carotene, lutein, and lycopene) from mixed standard solutions or from fruit extracts (kiwi fruits, tomato paste, pink grapefruit juice, kiwi-pineapple smoothie, and apricot nectar) was tested. The methodology was based on UV-Vis spectrophotometry and Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS). Results showed that relative concentrations of β-carotene, lutein, and lycopene in solvent were successfully determined by this technique with an error inferior to 6%. In real extracts, the procedure succeeded well in identifying the major carotenoid type of the fruit samples but also a more complex profile of a fruit mixture. The results also showed that accuracy of carotenoids determination by UV-Vis spectrophotometry-MCR-ALS in fruit extracts was conditioned by their spectral characteristics (III/II ratios and λmax), their relative proportion, and the extract purity. [ABSTRACT FROM AUTHOR]

The content of chlorophylls (Chl) (a+b), total carotenoids (x+c), and the pigment ratios of Chl a/b and Chls to carotenoids (a+b)/(x+c) of green leaves of five C4 plants were determined and compared to those of C3 plants. The C4 plants were: Pacific and Chinese silvergrass (Miscanthus floridulus and Miscanthus sinensis), sugar cane (Saccharum officinarum) as well as feed and sugar maize (Zea mays). The three C3 plants were beech, ginkgo, and oak. C4 plants possess higher values for the ratio Chl a/b (3.4-4.5) as compared to the C3 plants (2.6-3.3). Sugar maize had the highest values for Chl a/b (4.04-4.70) and exceptionally high contents of total carotenoids and consequently lower values for the ratio of (a+b)/(x+c) (mean: 3.75 ± 0.6). During autumnal senescence also C4 plants showed a faster decline of Chl b as compared to Chl a yielding high values for Chl a/b of 6 to 8. Chlorophylls declined faster than carotenoids yielding low (a+b)/(x+c) values below 1.0. [ABSTRACT FROM AUTHOR]

The present work aims to explore the potential to improve quality of purslane microgreens by combining water salinity and LED lighting during their cultivation. Purslane plants were grown in a growth chamber with light insulated compartments, under different lighting sources on a 16 h d−1 photoperiod—fluorescent lamps (FL) and two LED treatments, including a red and blue (RB)) spectrum and a red, blue and far red (RB+IR) LED lights spectrum—while providing all of them a light intensity of 150 µmol m−2 s−1. Plants were exposed to two salinity treatments, by adding 0 or 80 mM NaCl. Biomass, cation and anions, total phenolics (TPC) and flavonoids content (TFC), total antioxidant capacity (TAC), total chlorophylls (Chl) and carotenoids content (Car) and fatty acids were determined. The results showed that yield was increased by 21% both in RB and RB+FR lights compared to FL and in salinity compared to non-salinity conditions. The nitrate content was reduced by 81% and 91% when microgreens were grown under RB and RB+FR, respectively, as compared to FL light, and by 9.5% under saline conditions as compared with non-salinity conditions. The lowest oxalate contents were obtained with the combinations of RB or RB+FR lighting and salinity. The content of Cl and Na in the leaves were also reduced when microgreens were grown under RB and RB+FR lights under saline conditions. Microgreens grown under RB light reached the highest TPC, while salinity reduced TFC, Chl and Car. Finally, the fatty acid content was not affected by light or salinity, but these factors slightly influenced their composition. It is concluded that the use of RB and RB+FR lights in saline conditions is of potential use in purslane microgreens production, since it improves the yield and quality of the product, reducing the content of anti-nutritional compounds. [ABSTRACT FROM AUTHOR]

Microgreens are receiving increasing popularity as functional and healthy foods due to their nutritional value and high content of bioactive compounds. The aim of the present study was to evaluate the effects of nutrient deprivation through the regulation of nutrient solution (NS) feeding days on the plant growth and chemical composition of spinach microgreens. For this purpose, spinach microgreens were subjected to four different fertigation treatments—namely, 0 (control), 5, 10, and 20 NS feeding days before harvesting—and harvested tissues were evaluated with regard to fresh and dry yield, color of true leaves, antioxidant activity, and chlorophyll, carotenoid, and phenolic compound contents. The results of our study revealed that prolonged NS feeding (20 NS) resulted in the highest fresh yield and photosynthetic pigment contents (chlorophylls, lutein, and β-carotene). In contrast, mineral concentrations (P, K, Ca, and Mg) were the lowest for the 20 NS, whereas the control (0 NS) and 5 NS recorded the highest concentrations. Apart from that, spinach microgreens subjected to 10 NS treatment recorded 70.7% less nitrates, better mineral concentrations, 7.0% higher total ascorbic acid, similar polyphenol contents, higher DM%, and only 12.6% yield decrease compared to 20 NS treatment. In conclusion, although the highest overall fresh yield was recorded with the 20 NS treatment, the highest nitrate concentrations and the lowest mineral concentrations may raise food safety concerns. On the other hand, 10 NS treatment seems to be the most promising, since it combined high yields with high mineral concentrations and low nitrate concentrations, without compromising bioactive compound (e.g., polyphenols) contents, presenting a cost-effective and sustainable practice for microgreen cultivation. [ABSTRACT FROM AUTHOR]

In nature, soil salinity and fluctuating light (FL) often occur concomitantly. However, it is unknown whether salt stress interacts with FL on leaf photosynthesis, architecture, biochemistry, pigmentation, mineral concentrations, as well as whole-plant biomass. To elucidate this, tomato (Solanum lycopersicum) seedlings were grown under constant light (C, 200 μmol m−2 s−1) or FL (5-650 μmol m−2 s−1), in combination with no (0 mM NaCl) or moderate (80 mM NaCl) salinity, for 14 days, at identical photoperiods and daily light integrals. FL and salt stress had separate effects on leaf anatomy, biochemistry and photosynthetic capacity: FL reduced leaf thickness as well as nitrogen, chlorophyll and carotenoid contents per unit leaf area, but rarely affected steady-state and dynamic photosynthetic properties along with abundance of key proteins in the electron transport chain. Salt stress, meanwhile, mainly disorganized chloroplast grana stacking, reduced stomatal density, size and aperture as well as photosynthetic capacity. Plant biomass was affected interactively by light regime and salt stress: FL reduced biomass in salt stressed plants by 17%, but it did not affect biomass of non-stressed plants. Our results stress the importance of considering FL when inferring effects of salt-stress on photosynthesis and productivity under fluctuating light intensities. [ABSTRACT FROM AUTHOR]

Hydroponically grown loquat seedlings were subjected to increasing NaCl concentrations (0, 12, 24, and 48 mM) for 42 d. At the whole plant level, Na+ and Cl- accumulated proportionally to the salt treatments; however, Na+ accumulated prevalently in leaves whilst Cl- accumulated prevalently in stems. Reduction of leaf biomass was only observed in seedlings grown with 48 mM NaCl, whereas net photosynthesis declined along with increasing NaCl concentration and salinity led to general accumulation of glucose, reduction of mannitol and sorbitol, and changes in pigment composition in loquat leaves. Increasing level of salinity induced accumulations of both proline and H2O2 but not of malondialdehyde byproducts. Dramatic alteration of sugar patterns in the leaves poses serious concerns about possible effects of salinity to fruit production. Further research is necessary to investigate the concentration at which NaCl significantly compromises the yield of this economically important fruit species. [ABSTRACT FROM AUTHOR]

The stress tolerance index (STI) of leaf photosynthetic parameters was analysed in recombinant introgression lines of spring wheat (Triticum aestivum L.) grown under water stress of varying intensity in the simulated conditions of soil and soil-atmospheric drought. STI for the chlorophyll content was >1 regardless of experimental conditions. Carotenoids content increased only when soil drought occurred. Maximum quantum yield of PSII photochemistry was the most stable and stress-resistant parameter. Minimal fluorescence yield of the dark-adapted state was only sensitive to soil-atmospheric drought. Nonphotochemical quenching decreased under water stress, while parameters of the fast light curve based on chlorophyll fluorescence increased proportionally to the level of the stress load. We believe that these parameters are the most sensitive to the changes in the water supply of wheat plants, and are convenient for the rapid and noninvasive assessment of the wheat photosynthetic apparatus state under drought conditions. [ABSTRACT FROM AUTHOR]

The leaves of scorzonera are vulnerable to mechanical damage due to heavy rainfall or wind. The aim of the study was to determine the impact of pre-sowing exposure of scorzonera seeds to laser light on the mechanical strength of the leaves and the content of photosynthetic pigments. The research material consisted of scorzonera leaves obtained from seeds treated with He-Ne laser light at the wavelength of 632.8 nm, surface power density of 5 mW cm–2, and exposure time of 1, 5, 10, and 30 minutes. Young’s modulus measurements showed that the leaves of the plants grown from seeds subjected to laser light stimulation were characterized by better mechanical strength compared to the leaves of the control. The highest values of the Young’s modulus were recorded for scorzonera plants grown from seeds subjected to laser light exposure for 10 minutes. Exposure to light for a period of 1, 5 and 30 minutes significantly affected the content of chlorophylls and carotenoids in the leaves relative to the control. The largest increase in the content of photosynthetic pigments was recorded for 1 minute. The improvement in the mechanical strength of scorzonera leaves may reduce their vulnerability to mechanical damage during vegetation. [ABSTRACT FROM AUTHOR]

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Seedlings of Sinapis alba L. species (white/yellow mustard) were grown in nutrient solution containing different concentrations 50, 100, 250 and 500 mg/kg Cu for 10 days. Seedlings were measured and weighed at the end of the experiment. Leaf pigment concentration (chlorophylls a and b and carotenoids), tissular copper concentration and Biological Accumulation Coefficients (BAC) were determined. Copper content in Sinapis alba L. tissues reached 74.54 - 171.20 mg/kg dry mass, with highest values at high ambient concentration. BAC reached 1.49 at 50 mg/kg and was subunitary at higher concentrations, between 0.75 - 0.34. Shoot length and biomass emphasize a significant decrease at high ambient copper levels, while photosynthetic pigment concentrations did not decrease. These results indicate a limited tolerance of white mustard to high copper concentrations and a limited bioaccumulation potential of this metal. [ABSTRACT FROM AUTHOR]

Light-emitting diodes (LEDs) are a promising technology with a potential to improve the irradiance efficiency, light quality, and the light spectrum for increasing plant yield and quality. In this experiment, we investigated the impacts of various LED light qualities, including 100% red, 100% blue, 70% red + 30% blue, and 100% white, on the growth and photosynthesis, phytochemical contents, and mineral element concentrations in lettuce ( Lactuca sativa L. cv. 'Grizzly') in comparison to normal greenhouse conditions. Photon flux of 300 µmol m s was provided for 14 h by 120 LEDs set on a 60 cm × 60 cm sheet of aluminum platform in the growth chambers, where plants were grown for 60 d. Fresh mass per plant was significantly higher when grown under 100% blue and 70% red + 30% blue LEDs compared to the other environments including greenhouse conditions. Phytochemical concentrations and a nutritive value of lettuce were also significantly affected by the light treatments. Chlorophyll and carotenoid concentrations increased in the plants grown under 70% red + 30% blue LEDs compared to those grown in the greenhouse. Vitamin C content was 2.25-fold higher in the plants grown under 100% blue LEDs compared to those grown in the greenhouse. Higher photosynthesis and maximal quantum yield of PSII photochemistry were also observed in the plants treated with LED lights. The application of LED light led to the elevated concentrations of macro-and micronutrients in lettuce possibly because of the direct effect of LED light and lower stress conditions in the growth chambers compared to the greenhouse. Although the mechanism of the changes in lettuce grown under LED is not well understood, the results of this study demonstrated that LED light could be used to enhance the growth and nutritional value of lettuce in indoor plant production facilities. [ABSTRACT FROM AUTHOR]

Sarracenia is a genus of carnivorous plants characterised by leaves modified into pitchers which lure, trap and digest insects. The aim of this study was to analyse the photochemical efficiency and contents of photosynthetic pigments and phenolic compounds in different pitcher parts - operculum, wing, pitchertube upper part and pitcher-tube lower part of three morphologically different Sarracenia hybrids. The photochemical efficiency of the operculum and the pitcher-tube upper part was lower than that of the pitcher-tube lower part and wing, especially in hybrid B. In all hybrids, the wing had higher amount of chlorophyll a than other pitcher parts. In contrast, a higher amount of phenolic compounds, in particular anthocyanins, was measured in the operculum and the pitcher-tube upper part, parts which are red-coloured and participate in luring and trapping insects. Although there were some differences among the hybrids, the results show that amount of phenolic compounds and photosynthetic pigments as well as photochemical efficiency are related to the function of the pitcher part analysed. [ABSTRACT FROM AUTHOR]

The production of pigments by halophilic archaea has been analysed during the last half a century. The main reasons that sustains this research are: (i) many haloarchaeal species possess high carotenoids production availability; (ii) downstream processes related to carotenoid isolation from haloarchaea is relatively quick, easy and cheap; (iii) carotenoids production by haloarchaea can be improved by genetic modification or even by modifying several cultivation aspects such as nutrition, growth pH, temperature, etc.; (iv) carotenoids are needed to support plant and animal life and human well-being; and (v) carotenoids are compounds highly demanded by pharmaceutical, cosmetic and food markets. Several studies about carotenoid production by haloarchaea have been reported so far, most of them focused on pigments isolation or carotenoids production under different culture conditions. However, the understanding of carotenoid metabolism, regulation, and roles of carotenoid derivatives in this group of extreme microorganisms remains mostly unrevealed. The uses of those haloarchaeal pigments have also been poorly explored. This work summarises what has been described so far about carotenoids production by haloarchaea and their potential uses in biotechnology and biomedicine. In particular, new scientific evidence of improved carotenoid production by one of the better known haloarchaeon (Haloferax mediterranei) is also discussed. [ABSTRACT FROM AUTHOR]

Twenty herbs, showing medicinal benefits on human life, like Taraxacum officinale, Plantago lanceolata, Hypericum perforatum, Ocimum basilicum, Melissa officinalis, Mentha piperita, and others, were tested. The percentage content of pigments, i.e. chlorophylls, carotenoids, and flavonoids, in the chosen herbs was determined. The spectrophotometric method, which is quick and readily available, was used. Measurements required pigment extraction with a solvent. Ethanol was used for the determination of chlorophylls and carotenoids, and acetone for the determination of flavonoids. Hierarchical agglomerative cluster analysis was performed in order to confirm the experimental results. The study of flavonoids content showed an interesting regularity which can be used for the classification of herbs. Plants belonging to the Lamiaceae family showed the flavonoids content in the range from 0.18 % to 0.68 %, whereas those belonging to the Apiaceaehas family showed the flavonoids content in the 0.75-1.20 % range. [ABSTRACT FROM AUTHOR]

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This study examined the composition and properties of chlorophyll and carotenoid extracted from the leaves of several Mediterranean evergreen shrubs and subshrubs (Myrtus communis L., Pistacia lentiscus L., Thymus vulgaris L., Salvia officinalis L. and Laurus nobilis L.) commonly used as herbs and spices. In order to fully assess their composition over a wide polarity range, pigments were extracted by successive solvent extraction with hexane, 80% acetone and 96% ethanol. Agitation-assisted extraction (AAE), ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) were employed and compared regarding their effect on the pigments' yield and composition. Individual chlorophylls and carotenoids were analyzed by HPLC-DAD, while the content of total pigments and the extracts' antioxidant capacity were determined spectrophotometrically. Throughout the experiments, pheophytin a, b and b' were dominant chlorophyll molecules, while lutein and β-carotene were dominant carotenoids. Overall, the extracted pigments were determined as being in the range of 73.84–127.60 mg 100 g−1 and were the lowest in T. vulgaris, with no significant differences between other species. M. communis and P. lentiscus had the highest antioxidant capacities, showing a moderate positive correlation with carotenoid and chlorophyll levels. Significant differences were found in the levels of individual pigments with most of them showing a medium level of polarity due to the dissolution in acetone as a medium polar solvent. AAE and PLE demonstrated similar efficacy in the extraction of both carotenoids and chlorophylls; however, preference can be given to PLE, being a novel method with numerous advantages, e.g., shorter extraction time and lower solvent consumption. The examined plant species certainly expressed great diversity and showed the potential for application in the production of various functional products. [ABSTRACT FROM AUTHOR]

Sea buckthorn (Hippophae rhamnoides L. (HR)) leaf powders are the underutilized, promising resource of valuable compounds. Genotype and processing methods are key factors in the preparation of homogenous, stable, and quantified ingredients. The aim of this study was to evaluate the phenolic, triterpenic, antioxidant profiles, carotenoid and chlorophyll content, and chromatic characteristics of convection-dried and freeze-dried HR leaf powders obtained from ten different female cultivars, namely 'Avgustinka', 'Botaniceskaja Liubitelskaja', 'Botaniceskaja', 'Hibrid Percika', 'Julia', 'Nivelena', 'Otradnaja', 'Podarok Sadu', 'Trofimovskaja', and 'Vorobjovskaja'. The chromatic characteristics were determined using the CIELAB scale. The phytochemical profiles were determined using HPLC-PDA (high performance liquid chromatography with photodiode array detector) analysis; spectrophotometric assays and antioxidant activities were investigated using ABTS (2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) and FRAP (ferric ion reducing antioxidant power) assays. The sea buckthorn leaf powders had a yellowish-green appearance. The drying mode had a significant impact on the total antioxidant activity, chlorophyll content, and chromatic characteristics of the samples; the freeze-dried samples were superior in antioxidant activity, chlorophyll, carotenoid content, and chromatic profile, compared to convection-dried leaf powder samples. The determined triterpenic and phenolic profiles strongly depend on the cultivar, and the drying technique had no impact on qualitative and quantitative composition. Catechin, epigallocatechin, procyanidin B3, ursolic acid, α-amyrin, and β-sitosterol could be used as quantitative markers in the phenolic and triterpenic profiles. The cultivars 'Avgustinka', 'Nivelena', and 'Botaniceskaja' were superior to other tested cultivars, with the phytochemical composition and antioxidant activity. [ABSTRACT FROM AUTHOR]

Brassica oleracea var. acephala is known to have a strong tolerance to low temperatures, but the protective mechanisms enabling this tolerance are unknown. Simultaneously, this species is rich in health-promoting compounds such as polyphenols, carotenoids, and glucosinolates. We hypothesize that these metabolites play an important role in the ability to adapt to low temperature stress. To test this hypothesis, we exposed plants to chilling (8 °C) and additional freezing (−8 °C) temperatures under controlled laboratory conditions and determined the levels of proline, chlorophylls, carotenoids, polyphenols, and glucosinolates. Compared with that of the control (21 °C), the chilling and freezing temperatures increased the contents of proline, phenolic acids, and flavonoids. Detailed analysis of individual glucosinolates showed that chilling increased the total amount of aliphatic glucosinolates, while freezing increased the total amount of indolic glucosinolates, including the most abundant indolic glucosinolate glucobrassicin. Our data suggest that glucosinolates are involved in protection against low temperature stress. Individual glucosinolate species are likely to be involved in different protective mechanisms because they show different accumulation trends at chilling and freezing temperatures. [ABSTRACT FROM AUTHOR]

Given the important medicinal and nutritional value of wild edible greens, the last few years there is an increasing interest for their domestication and commercial exploitation. However, information concerning their adaptation to environmental conditions and their response to modern agricultural systems are scarce. In the present study, the effect of nutrient solution pH (4.0, 5.5 and 7.0) on the growth, chemical composition and inorganic nutrition of Taraxacum officinale and Reichardia picroides plants grown indoors in a floating hydroponic system was evaluated. Both species performed better at pH 5.5 and were slightly affected by pH 7.0, whereas pH 4.0 was not prohibitive for growth for both species, although R. picroides was less tolerant than T. officinale at low pH. Moreover, pH 4.0 did not severely affect nutrients uptake and transport within the plant tissues, suggesting that R. picroides susceptibility to low pH should not be attributed to nutrients imbalance. Nevertheless, low pH positively enhanced the content in total soluble solids, total phenolics, chlorophylls (a, b and total) and carotenoids, and decreased nitrates in both species. In conclusion, the studied species could be successfully grown in soilless systems with nutrient solutions of varied pH. Moreover, low pH levels (pH = 4.0) seemed to be beneficial to nutritional and dietary value in both species highlighting the potential of commercial cultivation under adverse conditions, especially in sustainable farming systems. [ABSTRACT FROM AUTHOR]

Torpedino di Fondi (TF) is a hybrid tomato landrace developed in Sicily and recently introduced in the south Lazio area along with the classical San Marzano (SM) cultivar. The present study aimed at characterizing TF tomatoes at both pink and red ripening stages, and at comparing them with traditional SM tomatoes. A multidisciplinary approach consisting of morphological, chemical (FT-ICR MS, NMR, HPLC, and spectrophotometric methods), and biological (antioxidant and antifungal in vitro activity) analyses was applied. Morphological analysis confirmed the mini-San Marzano nature and the peculiar crunchy and solid consistency of TF fruits. Pink TF tomatoes displayed the highest content of hydrophilic antioxidants, like total polyphenols (0.192 mg/g), tannins (0.013 mg/g), flavonoids (0.204 mg/g), and chlorophylls a (0.344 mg/g) and b (0.161 mg/g), whereas red TF fruits were characterized by the highest levels of fructose (3000 mg/100 g), glucose (2000 mg/100 g), tryptophan (2.7 mg/100 g), phenylalanine (13 mg/100 g), alanine (25 mg/100 g), and total tri-unsaturated fatty acids (13% mol). Red SM fruits revealed the greatest content of lipophilic antioxidants, with 1234 mg/g of total carotenoids. In agreement with phenolics content, TF cultivar showed the greatest antioxidant activity. Lastly, red TF inhibited Candida species (albicans, glabrata and krusei) growth. [ABSTRACT FROM AUTHOR]

Brassica oleracea var. acephala production and seed selection in the Mediterranean region is traditionally limited to private, family needs or small enterprises. In recent years it became popular, especially in the US, and known as a superfood due to the presence of specialized metabolites associated with health benefits, mainly from polyphenols, glucosinolates, and carotenoids groups. With the increasing popularity of this plant, there is a growing interest in its commercial production. Therefore, in the present work we aimed to study how seed origin influences the content of specialized metabolites in B. oleracea var. acephala. We grew plants from six different seed producers, in a hydroponic system under controlled conditions, and determined seed germination percentage, morphological characteristics, pigments, polyphenols, glucosinolates, and carotenoids content, as well as antioxidant activity. Seed origin influenced germination percentage, yield, and slightly morphological characteristic, but did not influence pigments, total polyphenols, phenolic acids, glucosinolates, and carotenoids content. However, content of flavonoids, ferulic, sinapinic, and, consequently, antioxidant activity was slightly different. [ABSTRACT FROM AUTHOR]