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9 pages, 741 KiB  
Article
Pruning and In-Season Canopy Manipulation Affects MidSouth Juice and Wine Phenolic Content
by Haley Williams, Eric Stafne, Yan Zhang and Sam Chang
Beverages 2024, 10(4), 98; https://doi.org/10.3390/beverages10040098 - 10 Oct 2024
Abstract
Low total soluble solids and high titratable acidity limit MidSouth use as a varietal red wine grape. While canopy management practices were reported not to have enough of an effect on these primary metabolites, they could potentially improve MidSouth secondary metabolites, broadening its [...] Read more.
Low total soluble solids and high titratable acidity limit MidSouth use as a varietal red wine grape. While canopy management practices were reported not to have enough of an effect on these primary metabolites, they could potentially improve MidSouth secondary metabolites, broadening its potential as a wine grape. Two studies assessed the effects of different canopy management treatments on monomeric anthocyanin pigments and total phenolic content in MidSouth juice and wine. The first study compared early pruning, early pruning with leaf removal, normal pruning with leaf removal, and normal pruning. Early pruning with leaf removal showed higher total phenolics in juice and wine in 2021 but lower levels in 2020. The second study evaluated leaf removal, shoot thinning, or neither leaf removal nor shoot thinning. Leaf removal resulted in higher anthocyanins and total phenolics in 2021 juice, while shoot thinning increased total phenolics in 2021 juice and both anthocyanins and phenolics in 2021 wine. Shoot thinning demonstrated the most consistent improvement in phenolic content. MidSouth grapes can produce a range of wine phenolic content, depending on canopy management and postharvest treatment. Further investigation is needed to understand yearly variations and optimize MidSouth for regional red wine production. Full article
(This article belongs to the Section Wine, Spirits and Oenological Products)
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15 pages, 1583 KiB  
Article
Proteomics Analysis on the Effects of Oxidative Stress and Antioxidants on Proteins Involved in Sterol Transport and Metabolism in Human Telomerase Transcriptase-Overexpressing-Retinal Pigment Epithelium Cells
by R. Scott Duncan, Andrew Keightley, Adam A. Lopez, Conner W. Hall and Peter Koulen
Int. J. Mol. Sci. 2024, 25(20), 10893; https://doi.org/10.3390/ijms252010893 - 10 Oct 2024
Abstract
Age-related macular degeneration (AMD) is the most prevalent ocular disease in the elderly, resulting in blindness. Oxidative stress plays a role in retinal pigment epithelium (RPE) pathology observed in AMD. Tocopherols are potent antioxidants that prevent cellular oxidative damage and have been shown [...] Read more.
Age-related macular degeneration (AMD) is the most prevalent ocular disease in the elderly, resulting in blindness. Oxidative stress plays a role in retinal pigment epithelium (RPE) pathology observed in AMD. Tocopherols are potent antioxidants that prevent cellular oxidative damage and have been shown to upregulate the expression of cellular antioxidant proteins. Here, we determined whether oxidative stress and tocopherols, using either normal cellular conditions or conditions of sublethal cellular oxidative stress, alter the expression of proteins mediating sterol uptake, transport, and metabolism. Human telomerase transcriptase-overexpressing RPE cells (hTERT-RPE) were used to identify differential expression of proteins resulting from treatments. We utilized a proteomics strategy to identify protein expression changes in treated cells. After the identification and organization of data, we divided the identified proteins into groups related to biological function: cellular sterol uptake, sterol transport and sterol metabolism. Exposure of cells to conditions of oxidative stress and exposure to tocopherols led to similar protein expression changes within these three groups, suggesting that α-tocopherol (αT) and γ-tocopherol (γT) can regulate the expression of sterol uptake, transport and metabolic proteins in RPE cells. These data suggest that proteins involved in sterol transport and metabolism may be important for RPE adaptation to oxidative stress, and these proteins represent potential therapeutic targets. Full article
(This article belongs to the Special Issue Retinal Diseases: From Molecular Pathology to Therapies—2nd Edition)
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13 pages, 4745 KiB  
Article
Effects of Zirconium-Based Crosslinkers with Different Zirconium Contents on Pigment Coating in Paper
by Hyeong-Hun Park, Chul-Hwan Kim, Tae-Gyeong Lee, Ju-Hyun Park, Min-Sik Park and Jae-Sang Lee
Appl. Sci. 2024, 14(20), 9187; https://doi.org/10.3390/app14209187 - 10 Oct 2024
Abstract
This study investigates the impact of zirconium-based KZC series crosslinkers with varying zirconium contents and the polyamine-based crosslinker (PBC) on the properties of coated paper, focusing on key performance metrics such as viscosity, wet rub and pick resistance, dry pick resistance, gloss, brightness, [...] Read more.
This study investigates the impact of zirconium-based KZC series crosslinkers with varying zirconium contents and the polyamine-based crosslinker (PBC) on the properties of coated paper, focusing on key performance metrics such as viscosity, wet rub and pick resistance, dry pick resistance, gloss, brightness, ink set-off, and print mottle. The findings reveal that crosslinkers’ type and concentration significantly influence the coating colors’ viscosity, with PBC demonstrating lower low shear viscosity at lower concentrations. The KZC series showed stable viscosity across a zirconium content range of 7% to 20%, and both crosslinker types enhanced wet rub resistance at higher concentrations. Notably, the KZC series, particularly KZC7, exhibited superior wet pick resistance at increased concentrations, highlighting its effectiveness in enhancing the durability of the coating layer. All crosslinkers maintained excellent dry pick resistance, ensuring robust coating performance. While gloss and brightness were generally unaffected, KZC20, which had the highest zirconium content, slightly reduced these optical properties. Ink set-off tests indicated that the KZC series performed better at lower concentrations, whereas higher concentrations led to increased ink set-off, potentially due to over-crosslinking. Print mottle remained consistent across all crosslinkers, indicating uniform coating quality. Overall, the zirconium-based KZC series significantly enhances wet resistance and maintains high performance across various properties, though it may slightly reduce gloss and brightness and increase ink set-off at higher concentrations. PBC offers a balanced performance profile, emphasizing the need for careful crosslinker type and concentration optimization to achieve the desired coating properties for specific applications. This comprehensive evaluation provides valuable insights for developing and optimizing high-performance coated papers. Full article
(This article belongs to the Special Issue Advances in Pulp and Paper Technologies 2nd Edition)
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18 pages, 2439 KiB  
Article
Phytochemical and Functional Properties of Fruit and Vegetable Processing By-Products
by Roberto Ciccoritti, Roberto Ciorba, Danilo Ceccarelli, Monica Amoriello and Tiziana Amoriello
Appl. Sci. 2024, 14(20), 9172; https://doi.org/10.3390/app14209172 - 10 Oct 2024
Abstract
Processing sustainability and the concept of zero waste discharge are of great interest for many industries. Every year, fruit and vegetable processing industries generate huge amounts of by-products, which are often intended for animal feed or discarded as waste, posing a problem to [...] Read more.
Processing sustainability and the concept of zero waste discharge are of great interest for many industries. Every year, fruit and vegetable processing industries generate huge amounts of by-products, which are often intended for animal feed or discarded as waste, posing a problem to both environmental and economic points of view. However, to minimize the waste burden, the valorization of these residues received increased interest. In fact, fruit and vegetable by-products are an excellent source of valuable compounds, such as proteins, dietary fibers, lipids, minerals, vitamins, phenolic acids, flavonoids, anthocyanins, carotenoids, and pigments, which can be recovered and reused, creating new business prospects from a circular economy perspective. Understanding the chemical characteristics of these materials is a key concern for their valorization and the identification of their most appropriate intended use. In this study, the phytochemical and functional properties of fruit and vegetable processing by-products (peel and pomace) were investigated. Samples of different plants (i.e., apple, black and orange carrot, cucumber, kumquat, mango, parsnip, peach, black plum) were analyzed using chemical analytical methods and characterized using Fourier Transform Mid-Infrared spectroscopy (FT-MIR). The results highlighted their high nutritional composition in terms of protein, lipids, fiber, and ash, as well as bioactive and antioxidant profiles. These characteristics make these residues suitable as natural ingredients for the development of high-added-value products in food, cosmetic, and pharmaceutical industries. Full article
(This article belongs to the Special Issue Application of Natural Components in Food Production)
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9 pages, 3790 KiB  
Communication
The Endogenous Expression of BMI1 in Adult Human Eyes
by Zhongyang Lu, Maria G. Morales, Shufeng Liu and Hema L. Ramkumar
Cells 2024, 13(19), 1672; https://doi.org/10.3390/cells13191672 - 9 Oct 2024
Abstract
BMI1, also known as B lymphoma Mo-MLV insertion region 1, is a protein in the Polycomb group that is implicated in various cellular processes, including stem cell self-renewal and the regulation of cellular senescence. BMI1 plays a role in the regulation of retinal [...] Read more.
BMI1, also known as B lymphoma Mo-MLV insertion region 1, is a protein in the Polycomb group that is implicated in various cellular processes, including stem cell self-renewal and the regulation of cellular senescence. BMI1 plays a role in the regulation of retinal progenitor cells and the renewal of adult neuronal cells. However, the presence, location, and quantification of BMI1 in the adult human eye have never previously been reported. In this study, we collected 45 frozen globes from eye banks, and ocular tissues were dissected. Protein was quantified by utilizing a custom electrochemiluminescence (ECL) assay developed to quantify the BMI1 protein. BMI1 was found in all ocular tissues at the following levels: the retina (1483.6 ± 191.7 pg/mL) and the RPE (296.4 ± 78.1 pg/mL). BMI1 expression was noted ubiquitously in the GCL (ganglion cell layer), the INL (inner nuclear layer), the ONL (outer nuclear layer), and the RPE (retinal pigment epithelium) via immunofluorescence, with higher levels in the inner than in the outer retinal layers and the RPE. These data confirm that BMI1 is expressed in the human retina. Further studies will illuminate the role that BMI1 plays in ocular cells. BMI1 levels are lower in aged retinas, possibly reflecting changes in retinal somatic and stem cell maintenance and disease susceptibility. Full article
(This article belongs to the Special Issue Retinal Pigment Epithelial Cells in Age-Related Macular Degeneration)
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16 pages, 4856 KiB  
Article
Conservation of Yuan Dynasty Caisson Paintings in the Puzhao Temple, Hancheng, Shaanxi Province, China
by Juanli Wang, Peng Fu, Ming Cao and Wenqiang Dong
Coatings 2024, 14(10), 1287; https://doi.org/10.3390/coatings14101287 - 9 Oct 2024
Abstract
Caisson paintings are an integral part of the unique interior decoration ceiling of traditional Chinese architecture. There are a large number of Yuan Dynasty caisson paintings in the Puzhao Temple, in Hancheng, Shaanxi Province, China. These caisson paintings have exquisite patterns and rich [...] Read more.
Caisson paintings are an integral part of the unique interior decoration ceiling of traditional Chinese architecture. There are a large number of Yuan Dynasty caisson paintings in the Puzhao Temple, in Hancheng, Shaanxi Province, China. These caisson paintings have exquisite patterns and rich colors, which are rare artistic treasures of the Yuan Dynasty. In the history of nearly 700 years, due to various environmental and human factors, the caisson paintings have experienced various degradation; for example, the paper of the caisson paintings is acidified, the surface is polluted, the color is faded, mottled, and it is difficult to identify. Therefore, their protection is vital. In order to ensure the scientific and targeted development of the protection scheme, this study conducted a comprehensive and in-depth analysis of the paper fibers, pigments, adhesives, wood supports, and pollutants of the caisson paintings and carried out a series of protection experiments in the field and laboratory, providing a step-by-step review of the protection treatment application for the caisson paintings. Mechanical and wet cleaning were used to remove the pollutants. The caisson painting was deacidified with a barium hydroxide ethanol solution, and the paper and pigments of the caisson painting were strengthened with water-based fluorine. Several conservation problems, such as the removal of pollutants, the deacidification of acidified paper, and the reinforcement of flaking paper and pigments, were solved. Meanwhile, good conservation and restoration results for caisson paintings were obtained. This research method of combining theory and practice has greatly improved the scientificity and success rate of conservation work. These research results provide valuable experience and reference for other caisson paintings in similar environments. Full article
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15 pages, 5124 KiB  
Article
Functionality and Scar Evaluation of the Donor Site in Extended Radial Forearm Flap Phalloplasty: How Affected Is the Arm in Day-to-Day Life?
by Mahmut Ozturk, Sascha Wellenbrock, Philipp Wiebringhaus, Marie-Luise Aitzetmüller-Klietz, Lara Küenzlen, Anna Burger, Sahra Nasim, Tobias Hirsch, Matthias Aitzetmüller-Klietz, Baksan Tav and Ulrich M. Rieger
J. Clin. Med. 2024, 13(19), 6004; https://doi.org/10.3390/jcm13196004 - 9 Oct 2024
Abstract
Background: The radial forearm flap remains the gold standard in phalloplasty in gender-affirming surgery due to its versatility and functional outcome, but the significant donor site morbidity and its impact on daily functioning and aesthetic perception remains understudied. This study provides valuable insights [...] Read more.
Background: The radial forearm flap remains the gold standard in phalloplasty in gender-affirming surgery due to its versatility and functional outcome, but the significant donor site morbidity and its impact on daily functioning and aesthetic perception remains understudied. This study provides valuable insights into the mid-term functional and aesthetic outcomes of the forearm in transgender individuals following radial forearm flap phalloplasty using widespread instruments for assessment scoring systems and for the evaluation of postoperative wound healing of surgical interventions in general. Methods: Between January 2013 and March 2018, a total of 47 patients underwent radial phalloplasty at AGAPLESION Markus Hospital, and 20 consented to participate in this cross-sectional, retrospective study evaluating functional and aesthetic outcomes post-radial forearm flap phalloplasty using standardized questionnaires (DASH, POSAS, and SBSES). A univariate median regression of each score was performed to determine the associations with selected variables, and correlation analyses between scores was performed using a nonparametric Spearman rank correlation. Results: Among the 20 participants, the median Quick DASH, DASH functionality, DASH sport and music, and DASH work scores indicated minimal to no functional impairment. Scar evaluations using the PSAS, OSAS, and SBSES scales showed overall patient satisfaction with minimal concerns regarding pigmentation and scar texture. Notably, an increase of 0.27 cm2 in wound surface area added one point to the DASH sport and music score (p = 0.037). Statistical analysis also demonstrated a significant correlation between functional and aesthetic assessment scores. Conclusions: The radial forearm phalloplasty donor site, evaluated by the PSAS, OSAS, and SBSES scales, leads to minimal or no functional impairment; however, the worsening of the DASH sport and music score with increasing wound surface reflects a direct relation between wound size and functional impairment. Full article
(This article belongs to the Special Issue Recent Advances on Reconstructive Urology and Prosthetic Surgery)
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18 pages, 8881 KiB  
Article
Investigation of Structural and Spectral Peculiarities of Fusarium sp. Indicator Pigment Bostrycoidin
by Anastasia Povolotckaia, Dmitrii Pankin, Vasiliy Novikov, Evgenii Borisov, Sergey Kuznetsov, Alexey Dorokhov, Anatoly Gulyaev, Elena Zavyalova, Rugiya Alieva, Sergey Akulov, Sergey Belousov and Maksim Moskovskiy
Molecules 2024, 29(19), 4765; https://doi.org/10.3390/molecules29194765 - 8 Oct 2024
Abstract
Bostrycoidin is one of the pigments produced by the Fusarium genus of fungi. On the one hand, it has significant pharmacological importance, while on the other hand, it serves as a presence marker of Fusarium infection in useful grain crops, fruits, and soils. [...] Read more.
Bostrycoidin is one of the pigments produced by the Fusarium genus of fungi. On the one hand, it has significant pharmacological importance, while on the other hand, it serves as a presence marker of Fusarium infection in useful grain crops, fruits, and soils. In this regard, the structural and optical properties of the bostrycoidin molecule were studied in the framework of density functional theory (DFT). The most stable geometry as well as higher-energy conformers and tautomers were investigated. The lowest-energy tautomer was found to be about 3 kcal/mol higher in energy than the most stable structure, resulting in relatively low population of this state. The obtained conformational rotamers associated with the rotation of the OMe group possess similar energy. The vibrational spectrum was modeled for the most stable conformer, and the most active peaks in the IR absorbance spectrum were assigned. Moreover, the electronic absorption spectrum was simulated within the time-dependent DFT approach. The obtained theoretical spectrum is in good agreement with the experimental data and the theoretically calculated longest-wavelength transition (HOMO–LUMO) was about 498 nm. Full article
(This article belongs to the Section Molecular Structure)
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31 pages, 3022 KiB  
Review
Age-Related Macular Degeneration (AMD): Pathophysiology, Drug Targeting Approaches, and Recent Developments in Nanotherapeutics
by Mahendra Singh, Riyakshi Negi, Alka, Ramachandran Vinayagam, Sang Gu Kang and Prashant Shukla
Medicina 2024, 60(10), 1647; https://doi.org/10.3390/medicina60101647 - 8 Oct 2024
Abstract
The most prevalent reason for vision impairment in aging inhabitants is age-related macular degeneration (AMD), a posterior ocular disease with a poor understanding of the anatomic, genetic, and pathophysiological progression of the disease. Recently, new insights exploring the role of atrophic changes in [...] Read more.
The most prevalent reason for vision impairment in aging inhabitants is age-related macular degeneration (AMD), a posterior ocular disease with a poor understanding of the anatomic, genetic, and pathophysiological progression of the disease. Recently, new insights exploring the role of atrophic changes in the retinal pigment epithelium, extracellular drusen deposits, lysosomal lipofuscin, and various genes have been investigated in the progression of AMD. Hence, this review explores the incidence and risk factors for AMD, such as oxidative stress, inflammation, the complement system, and the involvement of bioactive lipids and their role in angiogenesis. In addition to intravitreal anti-vascular endothelial growth factor (VEGF) therapy and other therapeutic interventions such as oral kinase inhibitors, photodynamic, gene, and antioxidant therapy, as well as their benefits and drawbacks as AMD treatment options, strategic drug delivery methods, including drug delivery routes with a focus on intravitreal pharmacokinetics, are investigated. Further, the recent advancements in nanoformulations such as polymeric and lipid nanocarriers, liposomes, etc., intended for ocular drug delivery with pros and cons are too summarized. Therefore, the purpose of this review is to give new researchers an understanding of AMD pathophysiology, with an emphasis on angiogenesis, inflammation, the function of bioactive lipids, and therapy options. Additionally, drug delivery options that focus on the development of drug delivery system(s) via several routes of delivery can aid in the advancement of therapeutic choices. Full article
(This article belongs to the Special Issue Retinal Diseases: Clinical Presentation and Novel Treatments)
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16 pages, 3634 KiB  
Article
Alleviation of NaCl Stress on Growth and Biochemical Traits of Cenchrus ciliaris L. via Arbuscular Mycorrhizal Fungi Symbiosis
by Jahangir A. Malik, Abdulaziz A. Alqarawi, Fahad Alotaibi, Muhammad M. Habib, Salah N. Sorrori, Majed B. R. Almutairi and Basharat A. Dar
Life 2024, 14(10), 1276; https://doi.org/10.3390/life14101276 - 8 Oct 2024
Abstract
Soil salinization, especially in arid and semi-arid regions, is one of the major abiotic stresses that affect plant growth. To mediate and boost plant tolerance against this abiotic stress, arbuscular mycorrhizal fungi (AMF) symbiosis is commonly thought to be an effective tool. So, [...] Read more.
Soil salinization, especially in arid and semi-arid regions, is one of the major abiotic stresses that affect plant growth. To mediate and boost plant tolerance against this abiotic stress, arbuscular mycorrhizal fungi (AMF) symbiosis is commonly thought to be an effective tool. So, the main purpose of this study was to estimate the role of AMF (applied as a consortium of Claroideoglomus etunicatum, Funneliformis mosseae, Rhizophagus fasciculatum, and R. intraradices species) symbiosis in mitigating deleterious salt stress effects on the growth parameters (shoot length (SL), root length (RL), shoot dry weight (SDW), root dry weight (RDW), root surface area (RSA), total root length (TRL), root volume (RV), root diameter (RD), number of nodes and leaves) of Cenchrus ciliaris L. plants through improved accumulations of photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll), proline and phenolic compounds. The results of this experiment revealed that the roots of C. ciliaris plants were colonized by AMF under all the applied salinity levels (0, 75, 150, 225, and 300 mM NaCl). However, the rate of colonization was negatively affected by increasing salinity as depicted by the varied colonization structures (mycelium, vesicles, arbuscules and spores) which were highest under non-saline conditions. This association of AMF induced an increase in the growth parameters of the plant which were reduced by salinity stress. The improved shoot/root indices are likely due to enhanced photosynthetic activities as the AMF-treated plants showed increased accumulation of pigments (chlorophyll a, chlorophyll b and total chlorophyll), under saline as well as non-saline conditions, compared to non-AMF (N-AMF) plants. Furthermore, the AMF-treated plants also exhibited enhanced accumulation of proline and phenolic compounds. These accumulated metabolites act as protective measures under salinity stress, hence explaining the improved photosynthetic and growth parameters of the plants. These results suggest that AMF could be a good tool for the restoration of salt-affected habitats. However, more research is needed to check the true efficacy of different AMF inoculants under field conditions. Full article
(This article belongs to the Special Issue Plant Biotic and Abiotic Stresses 2024)
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14 pages, 1302 KiB  
Review
Research Progress on Bioactive Substances of Beets and Their Functions
by Chun Bian, Lanyang Ji, Wei Xu, Shirong Dong and Nan Pan
Molecules 2024, 29(19), 4756; https://doi.org/10.3390/molecules29194756 - 8 Oct 2024
Abstract
As a globally cultivated and economic crop, beets are particularly important in the cane sugar and feed industries. Beet pigments are among the most important natural pigments, while various chemical components in beets display beneficial biological functions. Phenolic substances and betalains, as the [...] Read more.
As a globally cultivated and economic crop, beets are particularly important in the cane sugar and feed industries. Beet pigments are among the most important natural pigments, while various chemical components in beets display beneficial biological functions. Phenolic substances and betalains, as the main bioactive compounds, determine the functional characteristics of beets. This review categorizes the basic types of beets by the chemical composition of bioactive substances in their leaves, stems, and roots and emphatically summarizes the research progress made on the functions of two major substances in different types of beets: phenolic compounds and betalain pigments. This study provides useful insights for the comprehensive and effective application of beets in the health food and pharmaceutical industries. Full article
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20 pages, 2663 KiB  
Article
Stress Responses to Bark Beetle Infestations among Pine (Pinus sylvestris), Fir (Abies alba), and Beech (Fagus sylvatica) Trees
by Petr Soudek, Radka Podlipná, Lenka Langhansová, Kateřina Moťková, Marcela Dvořáková, Šárka Petrová, Daniel Haisel, Tetiana M. Satarova, Petre I. Dobrev, Alena Gaudinová, Pavlína Máchová, Adam Véle, Martin Fulín, Helena Cvrčková, Petr Hošek and Kateřina Berchová-Bímová
Forests 2024, 15(10), 1761; https://doi.org/10.3390/f15101761 - 8 Oct 2024
Abstract
Insect infestation triggers multiple defense responses in plants, both locally at the infection site and systemically throughout the plant, including the production of feeding deterrents, toxins, defensive proteins, enzymes, and secondary metabolites. Our study aimed to compare the endogenous levels of antioxidative enzymes, [...] Read more.
Insect infestation triggers multiple defense responses in plants, both locally at the infection site and systemically throughout the plant, including the production of feeding deterrents, toxins, defensive proteins, enzymes, and secondary metabolites. Our study aimed to compare the endogenous levels of antioxidative enzymes, photosynthetic pigments, phytohormones, total phenols, and flavonoids in bark-beetle-infested and uninfested trees. We evaluated the surviving trees in bark-beetle-infested stands, assessing both the condition and defense of uninfested and infested beech (Fagus sylvatica), pine (Pinus sylvestris), and fir (Abies alba) trees. Sampling was performed at six affected sites in the Czech Republic, targeting trees that were resilient to significant health deterioration caused by abiotic and biotic factors. The results showed different levels of most of the measured compounds in the three species. Among all the tested species, photosynthetic pigment levels showed the strongest association with infestation status, which was generally lower in the infested plants. For chlorophyll a, extremely significant reductions were observed from 123 ± 20.6 to 101 ± 17.9 μg/g dry weight (DW) in pine, from 231 ± 33.1 to 199 ± 22.2 μg/g DW in beech, and from 60 ± 5.66 to 51.3 ± 6.27 μg/g DW in fir. In contrast, enzymatic activities indicated only isolated instances of significant association, whereas antioxidative properties (total phenolic content, flavonoids, and 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity) were not significantly associated with infestation status. There was a statistically significant increase in glutathione reductase activity in infested fir and pine trees. However, this difference was not statistically significant in beech. In contrast, a significant increase in superoxide dismutase activity was detected in infected beech trees. Phytohormones have emerged as the most diverse group of analyzed compounds. Cytokinins were the most distinct, with many of them being significantly increased in infested pines, whereas both beech and fir showed only one significant association. Additionally, derivatives of jasmonic acid also showed a distinct pattern of change associated with bark beetle infestation, with the levels of three out of the four analyzed jasmonates being significantly decreased in infested pines, whereas no effects were observed in beeches and firs. Notably, many phytohormones were significantly elevated in the infested pine, whereas both beech and fir exhibited only one significant association. Overall, the data showed that pines responded differently to bark beetles than to beeches or firs. The greatest changes in phytohormones were observed in pine, whereas the most significant changes in photosynthetic pigments were observed in beech and fir trees. Full article
(This article belongs to the Section Forest Ecophysiology and Biology)
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14 pages, 3436 KiB  
Article
Chlorophyll and Carotenoid Metabolism Varies with Growth Temperatures among Tea Genotypes with Different Leaf Colors in Camellia sinensis
by Pengfei Xu, Jingbo Yu, Ruihong Ma, Yanyan Ji, Qiang Hu, Yihu Mao, Changqing Ding, Zhengzhen Li, Shibei Ge, Wei-Wei Deng and Xin Li
Int. J. Mol. Sci. 2024, 25(19), 10772; https://doi.org/10.3390/ijms251910772 - 7 Oct 2024
Abstract
The phenotype of albino tea plants (ATPs) is significantly influenced by temperature regimes and light conditions, which alter certain components of the tea leaves leading to corresponding phenotypic changes. However, the regulatory mechanism of temperature-dependent changes in photosynthetic pigment contents and the resultant [...] Read more.
The phenotype of albino tea plants (ATPs) is significantly influenced by temperature regimes and light conditions, which alter certain components of the tea leaves leading to corresponding phenotypic changes. However, the regulatory mechanism of temperature-dependent changes in photosynthetic pigment contents and the resultant leaf colors remain unclear. Here, we examined the chloroplast microstructure, shoot phenotype, photosynthetic pigment content, and the expression of pigment synthesis-related genes in three tea genotypes with different leaf colors under different temperature conditions. The electron microscopy results revealed that all varieties experienced the most severe chloroplast damage at 15 °C, particularly in albino cultivar Baiye 1 (BY), where chloroplast basal lamellae were loosely arranged, and some chloroplasts were even empty. In contrast, the chloroplast basal lamellae at 35 °C and 25 °C were neatly arranged and well-developed, outperforming those observed at 20 °C and 15 °C. Chlorophyll and carotenoid measurements revealed a significant reduction in chlorophyll content under low temperature treatment, peaking at ambient temperature followed by high temperatures. Interestingly, BY showed remarkable tolerance to high temperatures, maintaining relatively high chlorophyll content, indicating its sensitivity primarily to low temperatures. Furthermore, the trends in gene expression related to chlorophyll and carotenoid metabolism were largely consistent with the pigment content. Correlation analysis identified key genes responsible for temperature-induced changes in these pigments, suggesting that changes in their expression likely contribute to temperature-dependent leaf color variations. Full article
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23 pages, 2582 KiB  
Article
Effects of Salicylic Acid on Physiological Responses of Pepper Plants Pre-Subjected to Drought under Rehydration Conditions
by Fabrício Custódio de Moura Gonçalves, Luís Paulo Benetti Mantoan, Carla Verônica Corrêa, Nathália de Souza Parreiras, Luiz Fernando Rolim de Almeida, Elizabeth Orika Ono, João Domingos Rodrigues, Renato de Mello Prado and Carmen Sílvia Fernandes Boaro
Plants 2024, 13(19), 2805; https://doi.org/10.3390/plants13192805 - 7 Oct 2024
Abstract
Capsicum annuum L. has worldwide distribution, but drought has limited its production. There is a lack of research to better understand how this species copes with drought stress, whether it is reversible, and the effects of mitigating agents such as salicylic acid (SA). [...] Read more.
Capsicum annuum L. has worldwide distribution, but drought has limited its production. There is a lack of research to better understand how this species copes with drought stress, whether it is reversible, and the effects of mitigating agents such as salicylic acid (SA). Therefore, this study aimed to understand the mechanisms of action of SA and rehydration on the physiology of pepper plants grown under drought conditions. The factorial scheme adopted was 3 × 4, with three water regimes (irrigation, drought, and rehydration) and four SA concentrations, namely: 0 (control), 0.5, 1, and 1.5 mM. This study evaluated leaf water percentage, water potential of shoots, chlorophylls (a and b), carotenoids, stomatal conductance, chlorophyll a fluorescence, and hydrogen peroxide (H2O2) concentration at different times of day, water conditions (irrigation, drought, and rehydration), and SA applications (without the addition of a regulator (0) and with the addition of SA at concentrations equal to 0.5, 1, and 1.5 mM). In general, exogenous SA application increased stomatal conductance (gs) responses and modified the fluorescence parameters (ΦPSII, qP, ETR, NPQ, D, and E) of sweet pepper plants subjected to drought followed by rehydration. It was found that the use of SA, especially at concentrations of 1 mM in combination with rehydration, modulates gs, which is reflected in a higher electron transport rate. This, along with the production of photosynthetic pigments, suggests that H2O2 did not cause membrane damage, thereby mitigating the water deficit in pepper plants. Plants under drought conditions and rehydration with foliar SA application at concentrations of 1 mM demonstrated protection against damage resulting from water stress. Focusing on sustainable productivity, foliar SA application of 1 mM could be recommended as a technique to overcome the adverse effects of water stress on pepper plants cultivated in arid and semi-arid regions. Full article
(This article belongs to the Special Issue Drought Responses and Adaptation Mechanisms in Plants)
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25 pages, 946 KiB  
Review
Structure–Function Relationships and Health-Promoting Properties of the Main Nutraceuticals of the Cactus Pear (Opuntia spp.) Cladodes: A Review
by Meriyem Koufan, Basma Choukrane and Mouaad Amine Mazri
Molecules 2024, 29(19), 4732; https://doi.org/10.3390/molecules29194732 - 7 Oct 2024
Abstract
Over the past decade, several studies have established a direct link between functional foods, nutraceuticals, and a reduced risk of oxidative-stress-related diseases. Nutraceuticals, which encompass a variety of bioactive molecules, exhibit both nutritional and therapeutic properties. The cactus pear (Opuntia spp.) is [...] Read more.
Over the past decade, several studies have established a direct link between functional foods, nutraceuticals, and a reduced risk of oxidative-stress-related diseases. Nutraceuticals, which encompass a variety of bioactive molecules, exhibit both nutritional and therapeutic properties. The cactus pear (Opuntia spp.) is a plant genus with many species recognized as functional foods, largely attributed to their high content of nutraceuticals, including polyphenols, fatty acids, vitamins, amino acids, pigments, and phytosterols. These compounds of different structures and functions possess different biological activities, contributing to the health-promoting properties of cactus pear. This makes cactus pears a valuable plant for the food, cosmetic, and pharmaceutical industries. While extensive research has focused on the nutritional profile of cactus pear fruits, the cladodes have received comparatively limited attention. Notably, the nutritional composition of cladodes can exhibit considerable variability, influenced by species and growing conditions. Furthermore, although various bioactive compounds have been identified in cladodes, studies elucidating their mechanisms of action, health benefits, and potential therapeutic applications remain insufficient. Addressing these gaps is crucial for enhancing the understanding and utilization of cactus pear cladodes. This paper provides a comprehensive overview of the structure–function relationships of the main nutraceuticals found in cactus pear cladodes. It synthesizes data from recent and relevant literature to elucidate the content of these compounds in relation to species and geographical origin, while also detailing the main biological activities and health-promoting benefits associated with cactus pear cladodes. Full article
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