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Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function

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A special issue of Plants (ISSN 2223-7747). This special issue belongs to the section "Plant Physiology and Metabolism".

Deadline for manuscript submissions: 20 April 2026 | Viewed by 14556

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Special Issue Editors

Dr. Farhat Abbas

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Guest Editor

College of Horticulture, South China Agricultural University, Guangzhou 510642, China
Interests: aroma and color compounds; biosynthesis pathway; regulatory mechanism
Special Issues, Collections and Topics in MDPI journals

Dr. Yiwei Zhou

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Guest Editor

Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
Interests: utilization and genetic breeding of ornamental plant germplasm resources; integrated multi-omics analysis of the formation mechanisms of important traits; construction of efficient detection systems for aroma and color
Special Issues, Collections and Topics in MDPI journals

Dr. Yanguo Ke

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Guest Editor

College of Agriculture and Life Sciences, Kunming University, Kunming 650214, China
Interests: mechanism of aroma and color formation in ornamental horticultural plants

Special Issue Information

Dear Colleagues,

This Special Issue focuses on plant pigments, particularly anthocyanins, carotenoids, and betalains. We invite submissions that explore the complex biosynthetic pathways and diverse functional roles of these compounds. The objective is to collect research that investigates the genetic and molecular mechanisms regulating their production and the response to diverse environmental stimuli. We are particularly focused on elucidating their essential roles in plant growth, development, and interactions with the surrounding environment. We encourage submissions that examine the complex relationship between these pigments and plant coloration, highlighting how their presence and abundance contribute to the diversity of colors observed in plant tissues. Understanding the mechanisms of plant pigmentation enables researchers to comprehend how plants utilize color for environmental communication, attraction of pollinators and seed dispersers, and defense against biotic and abiotic stresses. We invite submissions that investigate advanced scientific methods for the detection and quantification of anthocyanins, carotenoids, and betalains in plants. As the demand for rapid, accurate, and non-destructive detection techniques increases, researchers are persistently advancing innovative methods for these pigments. Contributions must detail advanced methodologies, including spectroscopic analysis, imaging techniques, and high-throughput screening methods, while evaluating their advantages and limitations within the framework of plant pigment research.

This Special Issue seeks to present a thorough and interdisciplinary perspective on the diverse functions of anthocyanins, carotenoids, and betalains within plant biology. We encourage researchers across disciplines to present their recent discoveries, promoting new insights and enhancing our comprehension of plant pigmentation, its ecological and evolutionary importance, and the advancement of novel detection methodologies.

Dr. Farhat Abbas
Dr. Yiwei Zhou
Dr. Yanguo Ke
Guest Editors

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Plants is an international peer-reviewed open access semimonthly journal published by MDPI.

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Keywords

anthocyanins
carotenoids
betalains
natural plant pigments
biosynthesis
regulatory mechanism

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Published Papers (11 papers)

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Research

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19 pages, 3238 KB

Open AccessArticle

Multi-Omics Analysis Provides Insights into Developmental Tepal Coloration in Gloriosa superba ‘Passion Flame’

by Xinyi Zhou, Kuang Sheng, Tong Wu, Liangsheng Zhang, Yuwei Liang and Xiaojun Chang

Plants 2026, 15(2), 235; https://doi.org/10.3390/plants15020235 - 12 Jan 2026

Viewed by 231

Abstract

Gloriosa superba ‘Passion Flame’ (flame lily) is a distinctive ornamental plant characterized by its striking floral structure and vivid coloration. During flower development, flame lily tepals undergo a pronounced color transition from green at the bud stage to bright red with a yellow base at maturity, providing an excellent system for studying flower pigmentation in monocots. Here, we applied a multi-omics approach to examine metabolite accumulation and gene expression dynamics across four stages of flower development. Metabolomic profiling identified 240 flavonoids and four anthocyanins, among which pelargonidin-3-O-glucoside showed the highest relative abundance among red pigmentation. Transcriptome analysis revealed that seven key anthocyanin structural genes showed strong correlations with anthocyanin accumulation. In parallel, several chlorophyll degradation genes, including GsSGR and GsPPH, were upregulated during tepal maturation, suggesting transcriptional activation of chlorophyll degradation pathways concurrent with pigment accumulation. Co-expression network analysis further identified GsMYB75 and GsMYB114 as temporally distinct regulators associated with anthocyanin biosynthesis, acting together with bHLH, NAC, and AP2/ERF transcription factors. This study provides new insights into the pigment regulation in G. superba ‘Passion Flame’ and offers candidate regulatory components for future functional studies and the improvement of ornamental traits in monocotyledonous plants. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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20 pages, 11309 KB

Open AccessArticle

Elucidating Scent and Color Variation in White and Pink-Flowered Hydrangea arborescens ‘Annabelle’ Through Multi-Omics Profiling

by Yanguo Ke, Dongdong Wang, Zhongjian Fang, Ying Zou, Zahoor Hussain, Shahid Iqbal, Yiwei Zhou and Farhat Abbas

Plants 2026, 15(1), 155; https://doi.org/10.3390/plants15010155 - 4 Jan 2026

Viewed by 344

Abstract

The color and scent of flowers are vital ornamental attributes influenced by a complex interaction of metabolic and transcriptional mechanisms. Comparative analyses were performed to determine the molecular rationale for these features in Hydrangea arborescens, between the white-flowered variety ‘Annabelle’ (An) and its pink-flowered variant ‘Pink Annabelle’ (PA). Gas chromatography–mass spectrometry (GC–MS) detected 25 volatile organic compounds (VOCs) in ‘An’ and 21 in ‘PA’, with 18 chemicals common to both types. ‘An’ exhibited somewhat higher VOC diversity, whereas ‘PA’ emitted much bigger quantities of benzenoid and phenylpropanoid volatiles, including benzaldehyde, benzyl alcohol, and phenylethyl alcohol, resulting in a more pronounced floral scent. UPLC–MS/MS metabolomic analysis demonstrated obvious clustering of the two varieties and underscored the enrichment of phenylpropanoid biosynthesis pathways in ‘PA’. Transcriptomic analysis revealed 11,653 differentially expressed genes (DEGs), of which 7633 were elevated and linked to secondary metabolism. Key biosynthetic genes, including PAL, 4CL, CHS, DFR, and ANS, alongside transcription factors such as MYB—specifically TRINITY_DN5277_c0_g1, which is downregulated in ‘PA’ (homologous to AtMYB4, a negative regulator of flavonoid biosynthesis)—and TRINITY_DN23167_c0_g1, which is significantly upregulated in ‘PA’ (homologous to AtMYB90, a positive regulator of anthocyanin synthesis), as well as bHLH, ERF, and WRKY (notably TRINITY_DN25903_c0_g1, highly upregulated in ‘PA’ and homologous to AtWRKY75, associated with jasmonate pathway), demonstrating a coordinated activation of color and fragrance pathways. The integration of metabolomic and transcriptome data indicates that the pink-flowered ‘PA’ variety attains its superior coloring and aroma via the synchronized transcriptional regulation of the phenylpropanoid and flavonoid pathways. These findings offer novel molecular insights into the genetic and metabolic interplay of floral characteristics in Hydrangea. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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19 pages, 4347 KB

Open AccessArticle

Effects of Continuous Low-Level UV-B, Alone or in Combination with Blue Light, on Photosynthetic and Antioxidant Responses of Morphologically Distinct Red-Leaf Lettuce Cultivars

by Ivan A. Timofeenko, Mikhail Vereshchagin, Ekaterina Dranichnikova, Nikolay Sleptsov, Anna Abramova, Olga V. Buyko, Arina Manevich, Vladimir Kreslavski and Pavel Pashkovskiy

Plants 2025, 14(24), 3821; https://doi.org/10.3390/plants14243821 - 16 Dec 2025

Viewed by 635

Abstract

The physiological, biochemical, and morphometric responses of two lettuce cultivars (Lactuca sativa L.), Gypsy and Pomegranate Lace, which differ in terms of leaf morphology and anthocyanin pigmentation, were examined under moderate light (290 µmol m⁻² s⁻¹) with the addition of blue light (BL, peak at 450 nm), UV-B (peak at 306 nm), and their combinations. Continuous low-intensity UV-B (30 mW m⁻²) was applied for 48 h—during the day with white (WL, Red: 51%, Green: 38%, Blue: 11%) or white + blue (WL + BL, Red: 30%, Green: 22%, Blue: 48%) light and at night alone—to assess the effects of sustained UVR8 activation in the absence of visible light. In the Pomegranate Lace cultivar, which has wrinkled leaves and localized anthocyanin pigmentation, the combination of WL + BL + UV-B enhanced the chlorophyll and carotenoid contents, photosynthetic rate, and stomatal conductance, whereas respiration did not change. These coordinated changes indicate efficient integration of cryptochrome and UVR8 signaling, which sustains photochemical efficiency and stimulates phenolic and carotenoid accumulation, reinforcing antioxidant capacity. In the Gypsy cultivar, which is characterized by smooth leaves and uniform pigmentation, UV-B + BL increased g_S along with the rates of respiration and photosynthesis and improved PSII efficiency. However, both cultivars showed a decrease in biomass and leaf area. Nevertheless, both cultivars exhibited increased antioxidant capacity, but in Gypsy, the addition of BL or UV-B affected the antioxidant capacity and PSII photochemical efficiency more effectively than in the Pomegranate Lace, likely due to deeper penetration in leaves and lower reflectance. Thus, long-term low-intensity UV-B radiation acts as a regulatory spectral cue that differentially modulates photosynthetic and antioxidant pathways. Its integration with blue light enables cultivar-specific optimization of photochemical resistance and metabolic resilience. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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21 pages, 10278 KB

Open AccessArticle

Transcription Factor TeMADS6 Coregulates Carotenoid Biosynthesis and Chlorophyll Degradation Resulting in Yellow-Green Petal Color of Marigold (Tagetes erecta)

by Chunling Zhang, Ke Zhu, Chujun Huang, Luan Ke, Yafeng Wen, Hang Li, Chaolong Yang, Zhengguo Tao and Yanhong He

Plants 2025, 14(24), 3763; https://doi.org/10.3390/plants14243763 - 10 Dec 2025

Cited by 1 | Viewed by 404

Abstract

Marigold (Tagetes erecta) is an important ornamental and industrial crop valued for its high lutein content. Although petal pigmentation during inflorescence development involves coordinated chlorophyll degradation and carotenoid biosynthesis, the transcriptional mechanisms regulating these processes remain poorly understood. Here, we identified a MADS-box transcription factor, TeMADS6, that coordinately regulates chlorophyll and carotenoid metabolism in marigold. Constitutive overexpression of TeMADS6 resulted in yellow-green petals. HPLC analysis revealed that lycopene, antheraxanthin, violaxanthin, zeaxanthin, and lutein levels were substantially reduced in TeMADS6-overexpression lines, while chlorophyll content was significantly increased compared with wild-type plants. Transcriptome profiling revealed strong repressions of the carotenoid biosynthetic genes TePSY1 and TeHYDB in transgenic florets. Moreover, the chlorophyll degradation gene TeNYC1 and TePPH2 were significantly downregulated, whereas TeSGR2 was upregulated. Together, these findings demonstrate that TeMADS6 acts as a dual-function transcriptional regulator controlling both chlorophyll degradation and carotenoid biosynthesis. This study provides new genetic resources for manipulating petal color and enhancing lutein accumulation in marigold, and advance understanding of the transcriptional networks orchestrating pigment metabolism during flower development. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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22 pages, 21492 KB

Open AccessArticle

Transcriptomic and Metabolic Profiles of Apple Peels of Different Colors

by Pingxing Ao, Yan Ma, Kang Luo, Yumei Ding, Hongjia Zhang, Yue Xu, Shaojie Yuan, Meng Zhang, Hui Guo, Gengyun Li, Yan Zhao, Jianxiang Liu, Leifeng Zhao and Yun Zheng

Plants 2025, 14(21), 3304; https://doi.org/10.3390/plants14213304 - 29 Oct 2025

Viewed by 676

Abstract

Apple (Malus domestica) is a woody fruit tree belonging to the Rosaceae family, genus Malus. It has been widely reported that MYB transcription factors are critical regulators for the red color of apple peel by activating the expression of anthocyanin biogenesis genes. However, it is still not clear what the molecular mechanism for the yellow color of apple peel is. In order to investigate key genes and metabolites responsible for yellow coloration of apple peel, three strains of apples, “Venus Gold (Ype)” with yellow peel, “Yanfu8 (Mpe)” with medium red peel, and “Red love” with dark red peel, were selected in this study. Transcriptomic and metabolomic profiles were obtained for the peels of the three apple strains. After analyzing the transcriptomic profiles and being verified with qRT-PCR experiments, our results suggest that LAR1 is a critical gene for the yellow color of Ype peel. Analysis of metabolomic profiles revealed that the abundances of catechin and epicatechin in Ype peel were higher than those in Rpe, indicating an important reason for the yellow color of Ype peel. Furthermore, when comparing volatile metabolites from Ype, Mpe, and Rpe, hundreds of volatile metabolites show significantly different abundances, suggesting that apples with different peel colors have different odors. Our results uncover a novel metabolic mechanism for yellow coloration, where high expression of LAR1 promotes accumulation of catechin and epicatechin, providing the first integrated transcriptomic and metabolomic evidence for this pathway in apple peel. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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20 pages, 7618 KB

Open AccessArticle

Anatomical and Digital Image Analysis of Flavonoid-Mediated Grain Coloration in Rye (Secale cereale L.)

by Pavel A. Zykin, Elena A. Andreeva, Natalia V. Tsvetkova, Andrey N. Bulanov and Anatoly V. Voylokov

Plants 2025, 14(16), 2557; https://doi.org/10.3390/plants14162557 - 17 Aug 2025

Viewed by 3613

Abstract

Rye exhibits high diversity in grain coloration among small cereals, which is mainly linked to the presence of colored flavonoids synthesized in the outer layers of the kernel. This variability is not yet sufficiently described from colorimetric, cytological, and biochemical points of view. In this study, the localization of flavonoid pigments, anthocyanins and proanthocyanidins (PAs), was analyzed across different grain tissues in 26 rye lines with identified anthocyanin grain color genes. Grain coloration was objectively characterized using the CIELAB color coordinates and the GrainScan software for image analysis of individual grains. The distribution of anthocyanins and PAs was investigated through light microscopy and matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) on longitudinal and cross sections of the grains. The results revealed that violet-grained lines accumulate anthocyanins in the pericarp, while green-grained lines contain anthocyanins in the aleurone layer. MALDI-IMS confirmed the presence of specific anthocyanins: cyanidins in the pericarp of violet-grained lines and delphinidins in the aleurone layer of green-grained lines. All studied lines, except for the anthocyanin-less vi3 mutants, exhibited PAs in the brown-colored testa. Four main color groups of the rye grains (yellow, green, brown, and violet) could be clearly differentiated using the CIE color coordinate h°. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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21 pages, 7191 KB

Open AccessArticle

Variability in Anthocyanin Expression in Native Maize: Purple Totomoxtle as a Phenotypic Trait of Agroecological Value

by José Gregorio Joya-Dávila, Federico Antonio Gutiérrez-Miceli, Leslie Alondra Serrano-Gómez, Alexis Salazar-Navarro, Daniel González-Mendoza, Olivia Tzintzun-Camacho, Ana Martín Santos-Espinoza, Grisel Sánchez-Grajalez, Eraclio Gómez-Padilla and Jaime Llaven-Martínez

Plants 2025, 14(16), 2511; https://doi.org/10.3390/plants14162511 - 12 Aug 2025

Cited by 1 | Viewed by 1052

Abstract

Purple totomoxtle (maize husk) in native maize represents a phenotypic trait of cultural and agronomic significance within traditional Mesoamerican agroecosystems. This study evaluated the phenotypic expression of anthocyanins in vegetative and reproductive tissues of ten native maize genotypes, including inter-parental crosses derived from both pigmented and non-pigmented lines. Field trials were conducted under rainfed conditions in Chiapas, Mexico. Visual and quantitative assessments included pigmentation intensity, chlorophyll and carotenoid content, ear traits and appearance, grain health, and yield performance. Genotypes exhibiting the purple phenotype showed consistent pigment accumulation in stems, nodes, leaf sheaths, tassels, and bracts (totomoxtle), with statistically significant differences compared to non-pigmented controls. Anthocyanin content in totomoxtle increased by 30% during late developmental stages, whereas chlorophyll and carotenoid levels peaked during early vegetative growth. Pigmented materials displayed healthier grain, enhanced ear appearance, and higher yields, with the JCTM × LLMJ cross reaching 6.60 t ha⁻¹. These findings highlight the functional value of purple totomoxtle and its potential in agroecological programs aimed at resilience, genetic conservation, and integral resource utilization, providing useful criteria such as stable pigment expression and superior yield to guide sustainable reproduction strategies. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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12 pages, 3425 KB

Open AccessArticle

Disruption of ABI4 Enhances Anthocyanin Accumulation in Arabidopsis Seedlings Through HY5-Mediated Light Signaling

by Mingyang Zeng, Yan Wu, Shunfa Lin, Fang Zhang, Haiyan Jiang, Lixia Ma and Dong Liu

Plants 2025, 14(13), 1905; https://doi.org/10.3390/plants14131905 - 20 Jun 2025

Cited by 2 | Viewed by 1174

Abstract

The AP2/ERF transcription factor ABSCISIC ACID INSENSITIVE 4 (ABI4) plays diverse roles in plant development and responses to abiotic stress. However, its potential involvement in regulating anthocyanin biosynthesis is not fully understood. In this study, three different loss-of-function abi4 alleles (abi4-1, abi4-2, and abi4-101) were employed to investigate the role of ABI4 in the regulation of anthocyanin accumulation in Arabidopsis seedlings. These abi4 mutants exhibited significantly increased anthocyanin accumulation, which was associated with elevated expression of genes involved in anthocyanin biosynthesis. HY5 (LONG HYPOCOTYL 5), a central component of photomorphogenesis, acts as a key light-regulated molecular switch. Further analysis revealed that ABI4 requires HY5 to function as a negative regulator of anthocyanin biosynthesis. Additionally, loss of ABI4 resulted in heightened light sensitivity, leading to increased light-induced chlorophyll accumulation and chloroplast development, along with upregulation of photosynthesis-related genes. Interestingly, the light-hypersensitive phenotype of abi4 mutants was partially rescued by the loss of HY5 function. Taken together, these findings demonstrate that ABI4 negatively regulates anthocyanin accumulation in Arabidopsis seedlings through a HY5-dependent light signaling pathway. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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18 pages, 4298 KB

Open AccessArticle

Functional Characterization of Anthocyanin Biosynthesis-Related Dihydroflavonol 4-reductase (DFR) Genes in Blueberries (Vaccinium corymbosum)

by Yongyan Zhang, Sijian Guo, Zening Zhang, Ruide Li, Shitao Du, Siyi Hao and Chunzhen Cheng

Plants 2025, 14(10), 1449; https://doi.org/10.3390/plants14101449 - 13 May 2025

Viewed by 1474

Abstract

Dihydroflavonol 4-reductase (DFR) genes contribute greatly to anthocyanin biosynthesis in plants. Up to now, however, research on the DFR gene family and the key anthocyanin-related DFR members in blueberries (Vaccinium corymbosum) has been limited. In this study, we performed a genome-wide identification of the blueberry DFR gene family, identifying 36 VcDFR genes categorized into five subfamilies. Gene expression analysis showed that three Subfamily III members (VcDFR11/29/34) and four Subfamily V members (VcDFR4/7/30/33) are highly expressed in blueberry fruits, particularly at late ripening stages. Transient overexpression analysis in apple fruits verified the contributions of VcDFR11 and VcDFR30 to anthocyanin biosynthesis, with VcDFR11 showing better promoting effects. Blueberry fruit-based transient overexpression further confirmed the promoting effects of VcDFR11 on anthocyanin accumulation and the expression of anthocyanin-related structural genes (especially its downstream anthocyanindin synthase (ANS) and UDP-glucose: flavonoid 3-O-glycosyltransferase (UFGT) genes). The VcDFR11 promoter contains binding sites for both bHLH and MYB transcription factors (TFs). Consistently, yeast one-hybrid and dual-luciferase assays confirmed that anthocyanin-related VcMYB-1 and VcbHLHs can bind to and activate the VcDFR11 promoter. Furthermore, co-overexpressing VcMYB-1/VcbHLHs with VcDFR11 led to much higher anthocyanin accumulation than overexpressing VcDFR11 alone, indicating that these TFs positively regulate anthocyanin biosynthesis by upregulating VcDFR11. In summary, our study characterized the blueberry DFR gene family and demonstrated the role of VcDFR11 in anthocyanin biosynthesis. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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21 pages, 10507 KB

Open AccessArticle

Function of Anthocyanin and Chlorophyll Metabolic Pathways in the Floral Sepals Color Formation in Different Hydrangea Cultivars

by Yanguo Ke, Umair Ashraf, Dongdong Wang, Waseem Hassan, Ying Zou, Ying Qi, Yiwei Zhou and Farhat Abbas

Plants 2025, 14(5), 742; https://doi.org/10.3390/plants14050742 - 28 Feb 2025

Cited by 5 | Viewed by 2484

Abstract

Hydrangea (Hydrangea macrophylla) is distinguished by having sepals instead of real petals, a trait that facilitates color diversity. Floral color is largely predetermined by structural genes linked to anthocyanin production, but the genetic factors determining floral hue in this non-model plant remain unclear. Anthocyanin metabolites, transcriptome, and the CIEL*a*b* hue system were employed to elucidate the biochemical and molecular mechanisms of floral color formation in three hydrangea cultivars: ‘DB’ (deep blue), ‘LB’ (light blue), and ‘GB’ (green blue). UPLC-MS/MS identified 47 metabolites, with delphinidin, cyanidin, malvidin, petunidin, pelargonidin, and peonidin being prominent. Delphinidins were 90% of the primary component in ‘DB’. The dataset identifies 51 and 31 DEGs associated with anthocyanin, flavonoid, and chlorophyll biosynthesis, with CHS, CHI, F3H, F3′5′H, DFR, ANS, BZ1, and 3AT displaying the highest expression in ‘DB’. Notably, DFR (cluster-46471.3) exhibits high expression in ‘DB’ while being down-regulated in ‘LB’ and ‘GB’, correlating with higher anthocyanin levels in floral pigmentation. Comparative analyses of ‘LB’ vs. ‘DB’, ‘DB’ vs. ‘GB’, and ‘LB’ vs. ‘GB’ revealed 460, 490, and 444 differentially expressed TFs, respectively. WRKY, ERF, bHLH, NAC, and AP2/ERF showed the highest expression in ‘DB’, aligning with the color formation and key anthocyanin biosynthesis-related gene expression. The findings reveal the molecular mechanisms behind floral pigmentation variations and lay the groundwork for future hydrangea breeding programs. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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15 pages, 1745 KB

Open AccessReview

Zeaxanthin and Other Carotenoids: Roles in Abiotic Stress Defense with Implications for Biotic Defense

by Barbara Demmig-Adams, Amy K. Hodges, Stephanie K. Polutchko and William W. Adams III

Plants 2025, 14(17), 2703; https://doi.org/10.3390/plants14172703 - 30 Aug 2025

Cited by 2 | Viewed by 1596

Abstract

Xanthophylls are carotenoids with diverse roles in stress protection across all taxa of life. This review highlights chloroplast-localized xanthophylls (with a focus on zeaxanthin) of plants by presenting an overview of the protective effects of xanthophylls as well as the role of carotenoids as precursors of multiple plant stress hormones. It also examines the roles of xanthophylls and stress hormones in signaling cascades between the chloroplast and nuclear genes that control plant growth, development, and stress defenses. This overview addresses the biosynthetic pathways of xanthophylls and carotenoid-derived plant stress hormones, functions of xanthophylls in photoprotection of photosynthesis, carotenoids as essential human micronutrients, and roles of xanthophylls in membrane integrity. Attention is given to the involvement of zeaxanthin in both abiotic and biotic defense as well as its impact on components of the biotic defense system with contrasting targets. Examples for the multiple principal loops of signaling cascades between the chloroplast and nucleus, which are based on chloroplast redox state and modulated by xanthophylls, are summarized. This review integrates the role of chloroplast carotenoids in controlling light-use efficiency and providing photoprotection with their system-wide regulatory effects as precursors of carotenoid-derived plant stress hormones and modulators of chloroplast redox state. A better understanding of these connections is needed to guide development of plant lines with improved resilience and productivity in complex, changing, and challenging environments. Full article

(This article belongs to the Special Issue Anthocyanins, Carotenoids, and Betalains in Plants: From Biosynthesis to Function)

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