Plant Unsaturated Fatty Acids: Multiple Roles in Stress Response

Complexity Meets Risk-The Next Generation of Genome-Edited Plants Challenges Established Concepts for Environmental Risk Assessment in the EU

For 20 years, the environmental risk assessment (ERA) of genetically modified plants (GMPs) has used a comparative assessment approach, comparing the GMP to presumably safe and familiar non-modified plant varieties. With new genomic techniques, it is now possible to design complex GMP applications with systemic metabolic changes, resulting in novel plant phenotypes. These plant phenotypes can exhibit profoundly altered morphological, physiological, or compositional characteristics, intentionally lacking equivalence with parental plants and non-modified comparators. Through the analysis of case studies involving GMPs with modifications of complex metabolic pathways, we evaluate the current practice of the comparative safety assessment approach applied in ERA in the European Union and its ability to inform ERA, particularly regarding environmental risks. Our findings show that the existing approach has notable weaknesses when applied to complex GMP applications. We suggest complementing ERA with a hypothesis-driven assessment approach that considers various protection goals and relies on whole-plant experimental assessments to draw risk conclusions. As plant modifications become increasingly complex, such as the development of synthetic biology plants, conducting ecologically realistic assessments will be crucial for future ERA.

Acyl-CoA-binding proteins: bridging long-chain acyl-CoA metabolism to gene regulation

Acyl-Coenzyme A-binding proteins (ACBPs) sequester and transport long-chain acyl-Coenzyme A (LCA-CoA) molecules, key intermediates in lipid metabolism, membrane biogenesis, and energy production. In addition, recent research emphasizes their regulatory role in linking the metabolic state to gene expression. In animals, ACBPs coordinate acetyl-CoA metabolism and enzyme activity, thereby affecting gene expression through broad signaling networks. In plants, ACBPs contribute to development and stress responses, with hypoxia research showing their involvement in detecting LCA-CoA fluctuations to trigger genetic acclimation. This review explores ACBPs in LCA-CoA signaling and gene regulation, emphasizing their function as universal 'translators' of metabolic states for cellular acclimation. Further ACBP research will offer novel regulatory insights into numerous signaling pathways fundamental to health, development, and environmental responses across kingdoms.

Transcriptome and Metabolome Analyses of the Salt Stress Response Mechanism in Lonicera caerulea

Lonicera caerulea is a wild fruit species with high edible and medicinal value. However, the molecular regulation and metabolic mechanisms of L. caerulea under salt stress are still unclear. Salt stress causes damage to the cell membrane of L. caerulea and induces changes in malondialdehyde content, relative electrolyte leakage, leaves' stomatal opening, and the water loss rate. It also increases the activity of antioxidant enzymes and the content of soluble sugars. A comprehensive transcriptomic and metabolomic analysis of L. caerulea exposed to salt stress at four different (treatment) time intervals yielded a total of 99,574 unigenes and 1375 metabolites. Among these, 4081, 4042, and 4403 differentially expressed genes (DEGs) were identified in 12 transcriptomes, while 776, 832, and 793 differentially accumulated metabolites (DAMs) were detected in 12 metabolomes. The DEGs play important roles in several signaling pathways, including MAPK signaling, fatty acid metabolism, starch and sucrose metabolism, phenylpropanoid biosynthesis, and plant hormone signal transduction. KEGG pathway enrichment analysis revealed that these DEGs and DAMs are associated with flavonoid and lipid biosynthesis pathways. The combined transcriptomic and metabolomic analyses suggest that flavonoid and fatty acid compounds may be involved in regulating plant responses to salt stress. These findings will lay the foundation for the selection of L. caerulea germplasm resources and the expansion of its cultivation area. These research findings will lay the foundation for the cultivation of salt-tolerant new varieties of L. caerulea and their planting in saline-alkali soils.

Jasmonic Acid Signaling Pathway Mediates Decabromodiphenyl Ethane (DBDPE) Tolerance by Modulating Photosynthesis and Oxidative Stress in Sugar Beet: Insights from Integrative Physiological and Multiomics Analyses

Decabromodiphenyl ethane (DBDPE), an emerging ubiquitous contaminant, enters the food chain through crop bioaccumulation, threatening food safety. This study investigated the bioaccumulation, toxicity, and tolerance mechanisms of DBDPE in sugar beet. The results showed that DBDPE was absorbed by roots and transported to leaves in a constant proportion, with greater toxicity in leaves than in roots. Physiological analyses revealed that DBDPE induced chloroplastic dysfunction and oxidative stress in a concentration-dependent manner. The antioxidant system in response to DBDPE varied with exposure levels. Integrated transcriptomic, proteomic, and metabolomic analyses revealed that remodeling of jasmonic acid (JA) biosynthesis and consequent activation of JA signaling were critical for DBDPE tolerance. Exogenous JA and JA-Ile (active JA) maintained photosynthetic activity by protecting chloroplasts and mitigated oxidative damage by enhancing antioxidant system activity, thereby improving DBDPE tolerance. This study provides an insight into the development of effective mitigation strategies against DBDPE toxicity in crops.

P. Oliveira MB, Carpena M, Prieto MA. Therapeutic and Preventive Potential of Plant-Derived Antioxidant Nutraceuticals

Oxidative stress and its relation to the onset of several chronic diseases have been increasingly highlighted in recent years. In parallel, there has been an increasing interest in the antioxidant properties of phytochemicals. Phytochemicals are products of plant secondary metabolism, including structural polysaccharides, unsaturated fatty acids, pigments (chlorophylls, carotenoids, and anthocyanins), or phenolic compounds. Phytochemicals can be obtained from lower and higher plants, their fruits, and even from macro- or microalgae. Their diverse structural features are linked to different beneficial effects through various molecular mechanisms, contributing to disease prevention. Beyond antioxidant activity, many phytochemicals also display anti-inflammatory, antidiabetic, anti-obesity, and neuroprotective effects, which can be intertwined. Beyond these, other natural antioxidants can also be obtained from animal, fungal, and bacterial sources. Thus, a wide range of antioxidants have the potential to be used as nutraceuticals with chemopreventive effects on the onset of various diseases related to antioxidant stress. Given their enormous structural and sourcing diversity, the present work provides an updated insight into the therapeutic and preventive potential of plant-derived antioxidants and nutraceuticals.

SIZ1 SUMOylates and stabilizes WRI1 to safeguard seed filling and fatty acid biosynthesis under high-temperature stress

High-temperature stress hinders seed filling, reducing seed quality and crop yield. However, the molecular mechanisms underlying this process remain unclear. Here, we identify SAP AND MIZ1 DOMAIN-CONTAINING LIGASE1 (SIZ1) as a key regulator of seed filling under prolonged high temperatures in Arabidopsis (Arabidopsis thaliana). SIZ1 and WRINKLED1 (WRI1) are co-expressed during seed filling, and overexpressing either gene enhances seed filling and promotes fatty acid biosynthesis under high-temperature stress. Genetic and biochemical analyses revealed that SIZ1 stabilizes WRI1 by promoting its SUMOylation at Lys-257 and Lys-266, thereby inhibiting its interaction with the CULLIN3-based ubiquitin E3 ligase adaptor protein BTB/POZMATH (BPM) and preventing its ubiquitination and degradation. Mutating these SUMOylation sites accelerates WRI1 degradation, impairing its function in seed filling under high-temperature stress. Furthermore, high-temperature stress induces SIZ1 expression and reduces WRI1 levels, suggesting that SIZ1-mediated SUMOylation counteracts high-temperature stress-induced WRI1 instability. These findings establish SIZ1 as a crucial factor in maintaining WRI1 stability and seed filling under high-temperature stress, providing valuable genetic resources and a theoretical foundation for addressing prolonged high-temperature stress in agricultural production.

Ionic Homeostasis, Carbohydrate Metabolism, and Oxidative Balance Underlie Wild Soybean Resistance to Low Potassium Stress

The scarcity of potassium resources in farmland soils poses a major challenge to global food security. Wild soybean (Glycine soja), a valuable wild germplasm related to cultivated soybeans, is known for its high-stress resistance and adaptability. This study comprehensively compares two wild soybean ecotypes in terms of growth parameters, photosynthetic physiology, mineral ions and metabolite contents, and gene expression, aiming to clarify the regulatory mechanisms of low potassium stress tolerance in wild soybean seedlings' leaves. Results show that in barren-tolerant wild soybean (GS2), genes involved in potassium ion transport were significantly upregulated. This promotes potassium absorption and transport, maintaining a high K+ concentration and K+/Na+ ratio. Carbohydrate synthesis is enhanced in GS2, with increased sucrose and raffinose accumulation and a more active tricarboxylic acid (TCA) cycle. GS2 also strengthens the ascorbic acid-glutathione (ASA-GSH) cycle, along with promoting salicylic acid and 4-aminobutyric acid GABA synthesis, which boosts antioxidant capacity and reactive oxygen species (ROS) scavenging, maintaining oxidative balance. Under low potassium stress, GS2 accumulates unsaturated fatty acids, enhancing cell-membrane fluidity and providing a stress-resistant structural barrier. Overall, this study provides a basis for developing high-quality wild soybean resources and exploring genes for low potassium stress tolerance, which could contribute to improving cultivated soybeans' adaptability to potassium-deficient soils and ensuring global food production stability.

Bioactive lipids and allelopathic potential of the invasive plant Heracleum sosnowskyi: insights into its fatty acid composition, antimicrobial and cytotoxic effects

Sosnowsky's hogweed (Heracleum sosnowskyi Manden) is one of the most dangerous invasive plant, notorious with presence of toxic substances. At the same time H. sosnowskyi phytochemistry from perspective of applications in pharmacology, especially lipids have not been much studied. This study aims to analyse lipids of H. sosnowskyi, especially fatty acids, their composition, metabolism patterns and biological activity. Extraction possibilities of lipids from different parts of H. sosnowskyi have been studied and besides traditional solvents, so called green solvents can be used. In lipid extracts various positional and geometric isomers of fatty acids have been found and their concentrations and profiles differ amongst plant parts. Multifactor statistical analysis demonstrates the contribution of the metabolism of fatty acids in different parts of a plant. H. sosnowskyi lipid extracts demonstrate high antimicrobial activity and cytotoxic activity against cancer cell lines and so plant biomass after eradication can be used to obtain substances with high application potential in the bio-pharma industry.

Effect of the insecticide clothianidin on the photosynthetic electron transport chain in pea

Clothianidin (CL) is a neonicotinoid insecticide widely used in crop protection against insect pests. However, its effects on photosynthesis remain largely unknown. Here, by investigating the influence of CL at the concentrations of 22 and 110 μg/L on the primary processes of photosynthesis, membrane fluidity and structural changes of pea chloroplasts, we located several primary binding sites of this pesticide. Similar dynamics were observed for both concentrations. However, statistically significant differences were only found at 110 μg/L for all methods used. The light saturated rate of linear electron flow decreased mainly due to the disturbance of electron flow on the acceptor side of photosystem II (PSII) associated with the appearance of QB-nonreducing centers and empty QB binding sites of PSII. The functioning of the donor side of PSII, the activity of photosystem I (PSI) and the maximum quantum yield of PSII photochemistry (Fv/Fm) were not found to be significantly altered. Increased membrane fluidity and structural alterations of the thylakoid membrane led to a decrease in the development of the proton gradient ΔрН and membrane energization processes.

Metabolomic responses of wheat grains to olive mill wastewater and drought stress treatments

The present research aimed to assess the metabolomic responses of wheat to olive mill wastewater (OMWW) and drought stress treatments. Wheat plants were cultivated under controlled conditions with the following treatments: control (75% field capacity, FC), OMWW (75 ml L-1), drought stress (40% FC, applied 30 days after sowing), and a combined treatment of OMWW and drought stress. Drought stress alone reduced grain yield by 67%, while the OMWW-treated plants resulted in a 29% reduction under stress relative to the control. OMWW application improved soil properties, enhancing organic matter and nutrient levels. Wheat grains from OMWW-treated plants exhibited higher sugar content and related enzyme activities, indicating improved metabolism, with significant increases in starch, fructose, and glucose levels alongside stable invertase and sucrose phosphate synthase activities. The study also noted substantial changes in amino acids, fatty acids, and phenolic acids in plants subjected to OMWW and drought stress. These modifications indicate OMWW's capability to influence vital biochemical pathways and boost antioxidant capacities in wheat. In conclusion, OMWW proves to be an effective soil amendment that mitigates drought stress and contributes to the production of nutrient-rich, resilient wheat, underscoring its potential as a sustainable agricultural practice in water-scarce areas.

Physiological and Metabolic Responses of Wheat (Triticum aestivum L.) after One-Generation Exposure to Perfluorooctanesulfonic Acid (PFOS)

The pattern of plant responses, particularly on the seeds/grains metabolite profile, after generational exposure to contaminants is not well documented. Seeds from wheat cultivated in soil amended with PFOS at 0 and 25 mg/kg in the first generation were grown in clean soil to produce daughter plants and seeds in the second generation and assigned treatment combinations of 0-0 mg/kg PFOS and 25-0 mg/kg PFOS. Plant stress and responses including growth and biomass production, chlorophyll content, lipid peroxidation, and enzyme activity were measured over a short exposure period (21 days growth period). Biomass yields, elemental concentration, and grain metabolites were also measured after a long exposure period (92 days growth period). The daughter plants exhibited decreased chlorophyll content and lipid peroxidation in a short exposure period. The elemental concentrations were mostly not affected except for changes in microelements, except B, in the grains. In the metabolomics analysis, grains harvested from plants previously exposed to PFOS (i.e., 25-0 mg/kg PFOS) showed increased abundances of sucrose, linolenic acid, tryptophan, inositol-4-monophosphate, and ferulic acid, perhaps in response to adaptation to former stress. The current findings seem to suggest that one-generation exposure to PFOS does not cause detrimental effects on the next generation after the cessation of exposure. The results provide insights into the effects of generational exposure of plants to PFOS.

Identification of novel candidate genes for regulating oil composition in soybean seeds under environmental stresses

Introduction

A key objective of soybean breeding programs is to enhance nutritional quality for human and animal consumption, with improved fatty acid (FA) composition for health benefits, and expand soybean use for industrial applications.

Methods

We conducted a metabolite genome-wide association study (mGWAS) to identify genomic regions associated with changes in FA composition and FA ratios in soybean seeds influenced by environmental factors. This mGWAS utilized 218 soybean plant introductions (PIs) grown in two field locations in Virginia over two years.

Results

The mGWAS revealed that 20 SNPs were significantly associated with 21 FA ratios, while additional suggestive SNPs were found for 36 FA ratios, highlighting potential quantitative trait loci linked to FA composition.

Discussion

Many of these SNPs are located near or within the genes related to phytohormone-mediated biotic and abiotic stress responses, suggesting the involvement of environmental factors in modulating FA composition in soybean seeds. Our findings provide novel insights into the genetic and environmental factors influencing FA composition in oilseeds. This research also lays the foundation for developing stable markers to develop soybean cultivars with tailored FA profiles for different practical applications under variable growth conditions.

OsMbl1 Counteracts OsGdsl1-Mediated Rice Blast Susceptibility by Inhibiting Its Lipase Activity

Plant lectins have a significant impact on the defense against pathogens and insect attacks. The jacalin-related lectin OsMbl1 from rice (Oryza sativa L.) has been reported to play a crucial role in pattern-triggered immunity (PTI). However, the underlying mechanism remains unclear. In this study, we identified a GDSL-like lipase, OsGdsl1, that interacts with OsMbl1 both in vitro and in vivo. The OsGdsl1 protein, which has lipase activity, is localized in the lipid bodies and apoplast. The expression of OsGDSL1 is modulated upon exposure to Magnaporthe oryzae (M. oryzae) or plant hormones. Deletion of the OsGDSL1 gene not only improved the resistance of rice to M. oryzae, but also led to an increased ROS burst after chitin treatments. The expression of some pathogenesis-related (PR) genes was upregulated in the mutants. We also found that OsMbl1 inhibited the lipase activity of OsGdsl1 during infection with M. oryzae. Overall, our results suggest that OsGdsl1 negatively regulates rice immunity to M. oryzae infection by downregulating ROS bursts and PR gene expressions, while its lipase activity, which is inhibited by OsMbl1, contributes to the enhancement of rice innate immunity during M. oryzae infection.

Both a Growth-Defence Trade-Off and a Leaf N: P Stoichiometric Imbalance Can Account For Ectomycorrhizal Hyphae Inhibited Non-Host Plant Growth

Previous studies indicated that ectomycorrhizal (EM) hyphae can access non-host plant roots and inhibit their growth, with the underlying mechanisms remaining largely unexplored. This study established a tripartite co-culture system consisting of EM fungi supported Quercus Mongolica and non-host plants Arabidopsis thaliana or Setaria italica. Plant growth, nutrient concentrations, transcriptome, microbial communities and fatty acids were determined to comprehensively understand the effects of EM on non-host plants. The results showed that roots of non-host plants were colonised by EM hyphae of Scleroderma, which significantly inhibited non-host growth and decreased their leaf [N], but increased leaf [P] and leaf free fatty acid concentrations. A small amount of 15N was transferred from non-host to Q. mongolica leaves. Foliar N application alleviated EM hyphae inhibited non-host plant growth. Genes associated with plant-pathogen interaction and defence hormone responses were activated, but those involved in photosynthesis and growth hormone responses were suppressed in A. thaliana leaves. Our findings suggest that a growth-defence trade-off, in conjunction with a leaf N: P stoichiometric imbalance, may explain the observed inhibition of non-host plant growth by EM hyphae. This study provides insights into ectomycorrhiza mediated host and non-host plants interaction, which is important for plant community establishment.

Combining Linkage and Association Mapping Approaches to Study the Genetic Architecture of Verticillium Wilt Resistance in Sunflower

Sunflower Verticillium Wilt and Leaf Mottle (SVW), caused by Verticillium dahliae Kleb., is a globally prevalent disease affecting sunflower production. In this study, we identified a major quantitative trait locus (QTL) on chromosome 10 and other genomic regions associated with SVW resistance by integrating biparental and association mapping in sunflower populations from the National Institute of Agricultural Technology. Nine replicated field trials were conducted in highly infested V. dahliae reservoirs to assess disease incidence and severity. Both mapping populations were genotyped using double-digest restriction-site-associated DNA sequencing (ddRADseq). Association mapping with 18,161 SNPs and biparental QTL mapping with 1769 SNPs identified a major QTL on chromosome 10 explaining up to 30% of phenotypic variation for disease incidence at flowering and for the area under the disease progress curve for disease incidence, and which contributes to a lesser extent to disease severity reduction. Additional QTLs on chromosomes 17, 8, 9, 14, 13, and 11 were associated with reduced disease incidence, severity, or both. Candidate genes were identified within these associated regions, 39 of which are in the major QTL on Chromosome 10. These findings demonstrate the value of integrating complementary QTL mapping strategies for validating resistance loci and advancing sunflower breeding for SVW resistance.

PGPB-driven bioenrichment and metabolic modulation of Salicornia europaea under marine Aquaponic conditions

This study analyzed the secondary metabolite profile of Salicornia europaea inoculated with Brevibacterium casei EB3 and Pseudomonas oryzihabitans RL18 in aquaponic systems, exploring the metabolic mechanisms responsible for the observed shifts. Experiments were conducted in both microcosm and pilot-scale aquaponic setups to evaluate how these metabolic shifts vary across different system scales and their potential contributions to the observed increased accumulation of bioactive compounds with antioxidant and antimicrobial properties, including some phenolic acids, such as caffeic acid (154-fold), flavonoids (2.85-fold), and some unsaturated fatty acids, such as oct-3-enoic acid (32-fold). Metabolic profiling revealed shifts in pathways associated with plant growth and stress resilience, such as amino acid and phenolic biosynthesis. Additionally, differences in metabolic responses observed between microcosm and pilot-scale systems underscored the importance of understanding scaling effects. These findings highlight the potential for optimizing aquaponic systems by leveraging microbial-plant interactions to enhance ecological and economic outcomes. This approach offers valuable applications in nutrient recycling, phytopharmaceutical development, and the advancement of saline agriculture within integrated aquaculture frameworks.

Metabolic engineering of lipids for crop resilience and nutritional improvements towards sustainable agriculture

Metabolic engineering of lipids in crops presents a promising strategy to enhance resilience against environmental stressors while improving nutritional quality. By manipulating key enzymes in lipid metabolism, introducing novel genes, and utilizing genome editing technologies, researchers have improved crop tolerance to abiotic stresses such as drought, salinity, and extreme temperatures. Additionally, modified lipid pathways contribute to resistance against biotic stresses, including pathogen attacks and pest infestations. Engineering multiple stress-resistance traits through lipid metabolism offers a holistic approach to strengthening crop resilience amid changing environmental conditions. Beyond stress tolerance, lipid engineering enhances the nutritional profile of crops by increasing beneficial lipids such as omega-3 fatty acids, vitamins, and antioxidants. This dual approach not only improves crop yield and quality but also supports global food security by ensuring sustainable agricultural production. Integrating advanced biotechnological tools with a deeper understanding of lipid biology paves the way for developing resilient, nutrient-rich crops capable of withstanding climate change and feeding a growing population.

Harnessing Apple Cell Suspension Cultures in Bioreactors for Triterpene Production: Transcriptomic Insights into Biomass and Triterpene Biosynthesis

Plant cell suspension cultures offer a sustainable method for producing valuable secondary metabolites, such as bioactive pentacyclic triterpenes. This study established a high-triterpene-yielding cell suspension culture from the apple cultivar "Cox Orange Pippin". Through transcriptomic analysis and triterpene profiling across growth phases, we uncovered complex regulatory networks that govern biomass production and triterpene biosynthesis. Key biological processes, including cell cycle regulation, cell wall biosynthesis, lipid metabolism, and stress response mechanisms, play pivotal roles in culture dynamics. Differential gene expression linked to these processes revealed how the culture adapts to growth conditions and nutrient availability at each growth phase. Methyl jasmonate elicitation enhanced phenylpropanoid and flavonoid biosynthesis, along with specific triterpene production pathways, highlighting its potential for optimizing secondary metabolite production. Key enzymes, such as oxidosqualene cyclase 4 and a putative C-2α hydroxylase, were identified as promising targets for future metabolic engineering efforts. This study represents the first in-depth report on the molecular mechanisms underlying plant cell growth in bioreactors, specially focusing on a cell suspension culture derived from a semi-russeted apple cultivar. The findings reveal key regulatory pathways in biomass accumulation and triterpene production, offering valuable insights for optimizing bioreactor cultures for industrial applications.

Overexpression of Plastid Acetyl-CoA Carboxylase Confers Stress Tolerances with Increased Levels of Unsaturated Fatty Acids in the Marine Diatom Phaeodactylum tricornutum

Acetyl-coenzyme A carboxylases (ACCs) catalyze the initial reaction of fatty acid (FA) biosynthesis. The marine diatom Phaeodactylum tricornutum has two nuclear-encoded ACCs (PtACC1 (Phatr3_EG01955) and PtACC2 (Phatr3_J55209)), both which are homomeric and predicted to be localized in the plastids and the cytosol, respectively. In this study, we focused on stromal ACC1 by constructing P. tricornutum strains expressing GFP-tagged PtACC1 (ACCG strains) and confirmed that PtACC1 was localized in or around the pyrenoid. Here, we showed that unsaturated FAs (UFAs) composing the thylakoid membrane lipids increased in PtACC1 strains grown under high light conditions (190 µmol photons m-2 s-1), and that the content of triacylglycerol (TAG) and unsaturation ratios in TAG increased under oxidative stresses (with added 50 µM H2O2). ACCG strains showed faster growth rates than wild type under high light and/or oxidative stress conditions. These results suggest that cell proliferation is maintained by an accelerated recovery of PSII due to the increased UFAs in the thylakoid membrane in ACCG strains grown in high light, and that increased UFAs in ACCG cells enhanced the tolerance to oxidative stresses presumably due to the increased scavenging capacity of UFAs against reactive oxygen species. The introduction of plastidic ACC resulted in stimulating supply of UFAs to specific lipids that in turn enhanced tolerance to various stresses.

Analysis of salinity-induced metabolome changes in Indian mustard (Brassica juncea) roots and shoots: hydroponic versus microplot cultivation

BACKGROUND

Brassica juncea L. (family Brassicaceae) or Indian mustard is a fast-growing oilseed crop. Climate changes mean that it is very important to evaluate the effects of salinity stress on B. juncea. The aim of this study was therefore to show the metabolic effect of salinity stress on shoots and roots using two cultivation models - hydroponic and microplot - in different cultivars, including RH-725 and RH-761. Salinity levels of 5, 7.5, and 10 dS m⁻¹ were investigated, and compared with a control of 0 dS m⁻¹, using untargeted metabolomics with gas chromatography-mass spectrometry (GC-MS) post-silylation, focusing on metabolic markers such as proline and glycine-betaine.

RESULTS

A total of 56 metabolites were identified, with the most prevalent classes belonging to sugars (8), followed by organic acids (13), amino acids (11), and fatty acids/esters (11). Shoots were found to have a higher sugar content than roots. Increases in unsaturated fatty acids were also associated with salinity stress, compared with a decrease in saturated fatty acids. Absolute levels of proline and glycine-betaine correlated with salinity stress, with the largest increases detected in shoots grown under hydroponic conditions, particularly for the RH-761 cultivar. Multivariate data analyses revealed that roots were more affected than shoots, regardless of cultivation model.

CONCLUSION

These findings might explain the different metabolic behavior of B. juncea's roots and shoots under various levels of salinity, associated with higher levels of free sugars in shoots and lipids in roots. © 2024 Society of Chemical Industry.

Wild grown Portulaca oleracea as a novel magnetite based carrier with in vitro antioxidant and cytotoxicity potential

The latest research on nanotechnology through the new tailored scaffolds encompassed the therapeutic effects of natural compounds, and the unique properties of metallic nanoparticles offer new possibilities in emerging biomedical fields. Various strategies have been developed to address the limitations of existing therapeutic agents concerning specificity, vectorization, bioavailability, drug resistance, and adverse effects. In this study, the medicinal plant Portulaca oleracea L. and magnetite nanoparticles were used to develop an innovative target carrier system, designed to enhance the cytotoxic effect and overcome the main drawbacks (permeability and localization) of the phytoconstituents. The low-metabolite profile of Romanian wild-grown Portulaca oleracea L. exhibits a diverse range of hundred fifty-five compounds across various chemical categories (amino acids, peptides, fatty acids, flavonoids, alkaloids, terpenoids, phenolic acids, organic acids, esters, sterols, coumarins, nucleosides, lignans, and miscellaneous compounds). Morpho-structural and magnetic properties of the new phytocarrier were investigated using a variety of methods, including XRD, FTIR, Raman, SEM, DLS), and magnetic determinations. The MTT assay was conducted to evaluate in vitro the potential cytotoxicity on normal human dermal fibroblasts (NHDF), as well as on two tumoral cell lines: human osteosarcoma (HOS) and cervical cancer (HeLa). Results indicated that significant inhibition of both cancer cell lines' viability was exerted by the new phytocarrier compared to herbal extract. Furthermore, the results obtained for the total phenolic content and the antioxidant potential screening performed using the FRAP and DPPH assays were superior for the new carrier system. These findings suggest the potential biomedical applications of the developed carrier system and its promising implications for future research and development in the field.

Whole-Genome Identification of the Flax Fatty Acid Desaturase Gene Family and Functional Analysis of the LuFAD2.1 Gene Under Cold Stress Conditions

Fatty acid desaturase (FAD) is essential for plant growth and development and plant defence response. Although flax (Linum usitatissimum L.) is an important oil and fibre crop, but its FAD gene remains understudied. This study identified 43 LuFAD genes in the flax genome. The phylogenetic analysis divided the FAD genes into seven subfamilies. LuFAD is unevenly distributed on 15 chromosomes, and fragment duplication is the only driving force for the amplification of the LuFAD gene family. In the LuFAD gene promoter region, most elements respond to plant hormones (MeJA, ABA) and abiotic stresses (anaerobic and low temperature). The expression pattern analysis showed that the temporal and spatial expression patterns of all LuFAD genes in different tissues and the response patterns to abiotic stresses (heat and salt) were identified. Subcellular localisation showed that all LuFAD2-GFP were expressed in the endoplasmic reticulum membrane. RT-qPCR analysis revealed that LuFAD2 was significantly upregulated under cold, salt and drought stress, and its overexpression in Arabidopsis thaliana enhanced cold tolerance genes and reduced ROS accumulation. This study offers key insights into the FAD gene family's role in flax development and stress adaptation.

The comprehensive regulatory network in seed oil biosynthesis

Plant oils play a crucial role in human nutrition, industrial applications and biofuel production. While the enzymes involved in fatty acid (FA) biosynthesis are well-studied, the regulatory networks governing these processes remain largely unexplored. This review explores the intricate regulatory networks modulating seed oil biosynthesis, focusing on key pathways and factors. Seed oil content is determined by the efficiency of de novo FA synthesis as well as influenced by sugar transport, lipid metabolism, FA synthesis inhibitors and fine-tuning mechanisms. At the center of this regulatory network is WRINKLED1 (WRI1), which plays a conserved role in promoting seed oil content across various plant species. WRI1 interacts with multiple proteins, and its expression level is regulated by upstream regulators, including members of the LAFL network. Beyond the LAFL network, we also discuss a potential nuclear factor-Y (NF-Y) regulatory network in soybean with an emphasis on NF-YA and NF-YB and their associated proteins. This NF-Y network represents a promising avenue for future efforts aimed at enhancing oil accumulation and improving stress tolerance in soybean. Additionally, the application of omics-based approaches is of great significance. Advances in omics technologies have greatly facilitated the identification of gene resources, opening new opportunities for genetic improvement. Importantly, several transcription factors involved in oil biosynthesis also participate in stress responses, highlighting a potential link between the two processes. This comprehensive review elucidates the complex mechanisms underlying the regulation of oil biosynthesis, offering insights into potential biotechnological strategies for improving oil production and stress tolerance in oil crops.

Excessive leaf oil modulates the plant abiotic stress response via reduced stomatal aperture in tobacco (Nicotiana tabacum)

High lipid producing (HLP) tobacco (Nicotiana tabacum) is a potential biofuel crop that produces an excess of 30% dry weight as lipid bodies in the form of triacylglycerol. While using HLP tobacco as a sustainable fuel source is promising, it has not yet been tested for its tolerance to warmer environments that are expected in the near future as a result of climate change. We found that HLP tobacco had reduced stomatal conductance, which results in increased leaf temperatures up to 1.5°C higher under control and high temperature (38°C day/28°C night) conditions, reduced transpiration, and reduced CO2 assimilation. We hypothesize this reduction in stomatal conductance is due to the presence of excessive, large lipid droplets in HLP guard cells imaged using confocal microscopy. High temperatures also significantly reduced total fatty acid levels by 55% in HLP plants; thus, additional engineering may be needed to maintain high titers of leaf oil under future climate conditions. High-throughput image analysis techniques using open-source image analysis platform PlantCV for thermal image analysis (plant temperature), stomata microscopy image analysis (stomatal conductance), and fluorescence image analysis (photosynthetic efficiency) were developed and applied in this study. A corresponding set of PlantCV tutorials are provided to enable similar studies focused on phenotyping future crops under adverse conditions.

Metabolomic analyses reveal that graphene oxide alleviates nicosulfuron toxicity in sweet corn

Nicosulfuron can repress the growth and quality of sweet corn (Zea mays), and graphene oxide has been used for sustainable agriculture. However, the underlying mechanism of the toxicity of nicosulfuron that is mediated in sweet corn remains elusive. To explore the potential mechanism of GO-mediated nicosulfuron toxicity in sweet corn in this study, we investigated the effects of graphene oxide on nicosulfuron stress in the sweet corn sister inbred lines of H01 and H20. Furthermore, we performed a metabolomics analysis for the H01 and H20 under different treatments. The results showed that nicosulfuron severely affected the rate of survival, physiological parameters, photosynthetic indicators, and chlorophyll fluorescence parameters of corn seedlings, whereas foliar spraying with graphene oxide promoted the rate of survival under nicosulfuron toxicity. The metabolomics analysis showed that 70 and 90 metabolites differentially accumulated in the H01 and H20 inbred lines under nicosulfuron treatment, respectively. Graphene oxide restored 59 metabolites in the H01 seedlings and 56 metabolites to normal levels in the H20 seedlings, thereby promoting the rate of survival of the sweet corn seedlings. Compared with nicosulfuron treatment alone, graphene oxide resulted in 108 and 66 differential metabolites in the H01 and H20 inbred lines, respectively. A correlation analysis revealed that metabolites, such as doronine and (R)-2-hydroxy-2-hydroxylase-1,4-benzoxazin-3(4-hydroxylase)-1, were significantly correlated with the rate of survival, photosynthetic parameters and chlorophyll fluorescence parameters. Furthermore, metabolites related to the detoxification of graphene oxide were enriched in the flavonoid metabolic pathways. These results collectively indicate that graphene oxide can be used as a regulator of corn growth and provide insights into their use to improve crops in areas that are contaminated with nicosulfuron.

Chromosome-level genomes of two Bracteacoccaceae highlight adaptations to biocrusts

Biological soil crusts (biocrusts) cover the majority of the world's dryland ground and are a significant component of the vegetation-free surface of the planet. They consist of an intimate association of microbial organisms, lichens, bryophytes and fungi. Biocrusts are severely endangered by anthropogenic disturbances despite their importance. The genus Bracteacoccus (Sphaeropleales, Chlorophyta) is a ubiquitous component of biocrusts from extreme environments. Here, we present the chromosome-level genome sequences of two Bracteacoccus species, B. bullatus and B. minor. Genome comparisons with other Archaeplastida identify genomic features that highlight the adaptation of these algae to abiotic stresses prevailing in such environments. These features include horizontal gene transfer events mainly from bacteria or fungi, gains and expansions of stress-related gene families, neofunctionalization of genes following gene duplications and genome structural variations. We also summarize transcriptional and metabolic responses of the lipid pathway of B. minor, based on multi-omics analyses, which is important for balancing the flexible conversion of polar membrane lipids and non-polar storage lipids to cope with various abiotic stresses. Under dehydration and high-temperature stress conditions B. minor differs considerably from other eukaryotic algae. Overall, these findings provide insights into the genetic basis of adaptation to abiotic stress in biocrust algae.

Fatty acid desaturase 3-mediated α-linolenic acid biosynthesis in plants

Omega-3 fatty acids (ω3 FAs) are essential components of cell membranes that also serve as precursors of numerous regulatory molecules. α-Linolenic acid (ALA), one of the most important ω3 FAs in plants, is synthesized in both the plastid and extraplastidial compartments. FA desaturase 3 (FAD3) is an extraplastidial enzyme that converts linoleic acid (LA) to ALA. Phylogenetic analysis suggested that FAD3 proteins are distinct from FAD7 and FAD8 desaturases, which convert LA to ALA in plastids. Structural analysis of FAD3 proteins indicated a positive relationship between enzymatic activity and transmembrane pore length and width. An inverse relationship between temperature and ALA biosynthesis was also evident, with ALA accumulation decreasing with increasing temperature. These findings suggest that certain FAD3 enzymes are more effective at converting LA to ALA than others. This information could potentially be used to engineer crop plants with higher levels of ALA.

Metabolome profiling dissects the oat (Avena sativa L.) innate immune response to Pseudomonas syringae pathovars

One of the most important characteristics of successful plant defence is the ability to rapidly identify potential threats in the surrounding environment. Plants rely on the perception of microbe-derived molecular pattern chemicals for this recognition, which initiates a number of induced defence reactions that ultimately increase plant resistance. The metabolome acts as a metabolic fingerprint of the biochemical activities of a biological system under particular conditions, and therefore provides a functional readout of the cellular mechanisms involved. Untargeted metabolomics was applied to decipher the biochemical processes related to defence responses of oat plants inoculated with pathovars of Pseudomonas syringae (pathogenic and non-pathogenic on oat) and thereby identify signatory markers that are involved in host or nonhost defence responses. The strains were P. syringae pv. coronafaciens (Ps-c), P. syringae pv. tabaci, P. syringae pv. tomato DC3000 and the hrcC mutant of DC3000. At the seedling growth stage, metabolic alterations in the Dunnart oat cultivar (tolerant to Ps-c) in response to inoculation with the respective P. syringae pathovars were examined following perception and response assays. Following inoculation, plants were monitored for symptom development and harvested at 2-, 4- and 6 d.p.i. Methanolic leaf extracts were analysed by ultra-high-performance liquid chromatography (UHPLC) connected to high-definition mass spectrometry. Chemometric modelling and multivariate statistical analysis indicated time-related metabolic reconfigurations that point to host and nonhost interactions in response to bacterial inoculation/infection. Metabolic profiles derived from further multivariate data analyses revealed a range of metabolite classes involved in the respective defence responses, including fatty acids, amino acids, phenolic acids and phenolic amides, flavonoids, saponins, and alkaloids. The findings in this study allowed the elucidation of metabolic changes involved in oat defence responses to a range of pathovars of P. syringae and ultimately contribute to a more comprehensive view of the oat plant metabolism under biotic stress during host vs nonhost interactions.

Diffusive Phyllosphere Microbiome Potentially Regulates Harm and Defence Interactions Between Stephanitis nashi and Its Crabapple Host

Pear lace bug (Stephanitis nashi) is a significant herbivorous pest, harbouring a diverse microbiome crucial for crabapple (Malus sp.) host adaptation. However, the mutual influence of S. nashi- and plant-associated microbiomes on plant responses to pest damage remains unclear. This study found that S. nashi damage significantly altered bacterial community structure and reduced bacterial evenness in the crabapple phyllosphere. Notably, bacterial diversity within S. nashi was significantly lower than that in the environment, potentially influenced by insect developmental stage, bacterial diffusion stage and endosymbiont species number and abundance. Extensive bacterial correlation and diffusion effect between S. nashi and adjacent plant environments were observed, evident in a gradual decrease in bacterial diversity and an increase in bacterial acquisition ratio from soil to phyllosphere to S. nashi. Correspondingly, S. nashi significantly impacted the metabolic response of crabapple leaves, altering pathways involved in vitamin, amino acid and lipid metabolism and so forth. Furthermore, association analysis linked these metabolic changes to phyllosphere bacterial alterations, emphasizing the important role of diffusive phyllosphere microbiome in regulating S. nashi-crabapple interactions. This study highlights bacterial diffusion effect between insect and plants and their potential role in regulating insect adaptability and plant defence responses, providing new insights into plant-insect-microbiome interactions.

Effect of melatonin on the contents of fatty acids and antioxidants of saffron

Early leaf senescence at the end of the growing season poses a significant challenge in saffron cultivation. While changes in leaf composition during senescence have been extensively documented in various plants, similar studies on saffron remain unexplored. Furthermore, there has been no investigation into the potential role of melatonin in delaying leaf senescence in saffron. This study aimed to examine the changes in saffron leaf composition and evaluate the effects of melatonin foliar application during the late growth stage. The research was conducted over two consecutive cropping years (2020-2021 and 2021-2022). In the first experiment, five concentrations of melatonin (0, 50, 100, 150, and 200 μM) were applied as foliar sprays to assess their effects on fatty acid composition and plant greenness. The second experiment involved varying melatonin concentrations and two application timings (124 and 131 days after germination) to study their impact on antioxidant enzyme activity. Both experiments were designed as factorial trials within a completely randomized block design with three replicates. The results demonstrated that treatment with 100 μM melatonin significantly increased the production of fatty acids, including C8:0 (67.60 %), C10:0 (98.66 %), C12:0 (40.73 %), and C18:0 (35.32 %) compared to the untreated control. Also, the highest activities of ascorbate peroxidase and catalase enzymes were observed with 100 μM melatonin applied 124 days after germination. On the same day, the highest total protein content was recorded with 50 μM melatonin, although it was not significantly different from the 100 μM treatment. In conclusion, the 100 μM melatonin treatment was found to be the most effective in enhancing plant greenness, modifying fatty acid composition, boosting antioxidant enzyme activity, and increasing total protein content. However, the timing of melatonin application emerged as a critical factor warranting careful consideration. These findings highlight the promising role of melatonin in improving the physiological and biochemical attributes of saffron plants.

Sprayable solutions containing sticky rice oil droplets reduce western flower thrips damage and induce changes in Chrysanthemum leaf chemistry

Thrips are one of the most challenging pests in agricultural crops, including Chrysanthemum. In this study we tested via two plant assays whether solutions containing sticky rice germ oil (RGO) droplets could effectively trap thrips and lower thrips damage on Chrysanthemum. In the first assay, we additionally assessed the metabolomic effects of these RGO droplet sprays and thrips presence on plant chemistry via 1H NMR and headspace GC-MS on multiple timepoints to investigate which plant metabolites were affected by spraying and their potential relation to plant resistance against thrips. In the second assay, we tested the individual RGO solution constituents against thrips. Our results suggested that the adhesive RGO droplets were not effective as a physical trap as only three out of 600 adult thrips were caught at the achieved coverage. However, average thrips damage was still reduced up to 50% and no negative effects on plant growth were observed up to 25 days. Results from the second plant assay indicated that the individual constituents of the solution containing RGO droplets may have direct effects against thrips. Metabolomics analysis of sprayed leaves via headspace GC-MS and 1H NMR indicated that fatty acids and several volatile compounds such as 4(10)-thujene (sabinene), eucalyptol, cis-4-thujanol, and isocaryophyllene were highest on day 10, while sucrose, malic acid, o-Cymene, and 3-Methyl-2-butenoic acid were highest on day 25. Plants with thrips showed higher flavonoid, carbohydrate and glutamine acetic acid levels, and lower fatty acids and malic acid levels. RGO application increased the levels of fatty acids and alcohols present on top of and inside the Chrysanthemum leaves, while decreasing the concentrations of volatile compounds such as eucalyptol, chrysanthenone and eugenol in the Chrysanthemum leaves. Most interestingly, the thrips effect on the plant metabolome was no longer visible in RGO treated plants at the later harvesttime, suggesting that RGO application may overrule or prevent the metabolomic effects of thrips infestation. In conclusion, our study provides new information on how the application of a new plant-based plant protection product affects insect herbivores and alters crop phytochemistry for improved herbivore resistance.

Genome assembly and population analysis of tetraploid marama bean reveal two distinct genome types

Tylosema esculentum (marama bean), an underutilized orphan legume native to southern Africa, holds significant potential for domestication as a rescue crop to enhance local food security. Well-adapted to harsh desert environments, it offers valuable insights into plant resilience to extreme drought and high temperatures. In this study, k-mer analysis indicated marama as an ancient allotetraploid legume. Using 21.5 Gb of PacBio HiFi data, the genome was assembled with two assemblers, HiCanu and Hifiasm, followed by scaffolding with Omni-C data from Dovetail Genomics (Cantata Bio) using HiRise, resulting in a 558.78 Mb assembly with near chromosome-level continuity (N50 = 22.68 Mb, L50 = 8). Repeats accounted for 58.43% of the genome. Phylogenetic analysis indicated a close relationship with Bauhinia variegata and Cercis canadensis, diverging approximately 27.22 and 31.68 million years ago (Ma), respectively. Whole-genome duplication (WGD) analysis revealed an ancient duplication event in marama. Gene family analysis revealed expanded families enriched in pathways related to stress adaptation, energy metabolism, and environmental signaling, including the spliceosome, citrate cycle, and carbon fixation pathways. These findings highlight marama's resilience to arid environments. In contrast, contracted gene families associated with secondary metabolite biosynthesis and defense pathways suggest a trade-off, potentially due to reduced pathogen pressure. Marama-specific genes were enriched in amino acid catabolism pathways, potentially playing roles in stress signaling and energy regulation. Core gene families shared with other legumes were enriched in conserved pathways, such as photosynthesis and hormone signaling, which are fundamental for plant growth and survival. Population analysis of geographically diverse samples revealed two distinct clusters, though phenotypic differences remain unclear. Overall, this study presents the first high-quality genome assembly of marama bean, offering a valuable genomic reference for understanding its unique biology and highlighting its potential for crop improvement in challenging environments.

Agronomic characteristics, mineral nutrient content, antioxidant capacity, biochemical composition, and fatty acid profile of Iranian pistachio (Pistacia vera L.) cultivars

BACKGROUND

Pistachio (Pistacia vera L.) nuts are among the most popular nuts. The pistachio cultivars are tolerant to both drought and salinity, which is why they are extensively grown in the arid, saline, and hot regions of the Middle East, Mediterranean countries, and the United States.

RESULTS

This study evaluated the agronomic and chemical characteristics of 10 pistachio cultivars ('Abbasiali', 'AhmadAghaei', 'Akbari', 'Chrook', 'Fandoghi', 'KalehGhoochi', 'Momtaz', 'Rezaei', 'Sefied', and 'Shahpasand'). Total phenolic content, antioxidant capacity, fruit mineral elements, soluble protein content, kernel-oil content, and fatty-acid composition were determined in 60 fruits (20 fruits per replication). Leaf mineral elements were determined in 450 leaves (150 leaves per replication). Significant differences were observed (p < 0.05) among the cultivars, with the coefficient of variation (CV) ranging from 1.03 (unsaturated fatty acids) to 115.16% (early nut splitting). Flower buds varied from 4 ('AhmadAghaei') to 7 ('Momtaz'), and fruit per bunch ranged from 11 ('Abbasiali') to 21 ('Momtaz'). Hull percentage ranged from 36.8 ('KalehGhoochi') to 43.1% ('Chrook'), and nut percentage ranged from 56.3 ('Chrook') to 62.4% ('KalehGhoochi'). Iron content in leaves ranged from 267 ('Chrook') to 367 mg/kg ('Rezaei'), while iron in fruits ranged from 65.72 ('Fandoghi') to 81.90 mg/kg ('Sefied'). Total phenolic content varied from 99.9 ('Rezaei') to 184.30 mg/g ('Fandoghi'), and antioxidant activity ranged from 39.14 ('Shahpasand') to 82.89% ('Sefied'). Oil content ranged from 49.26 ('Rezaei') to 67.72% ('AhmadAghaei'), with oleic acid between 48.4 ('Rezaei') and 55.55% ('KalehGhoochi'). Leaf phosphorus positively correlated with split nut percentage (r = 0.669) and negatively with blank nut percentage (r = -0.734). Fruit potassium strongly correlated with total phenolics (r = 0.917) and oleic acid (r = 0.654). Multiple regression analysis showed that blank nut percentage was negatively correlated with leaf zinc (β = -0.77) and positively with antioxidants (β = 0.77). Early nut splitting showed a negative correlation with antioxidants (β = -0.72). The first three principal components (PC1 = 22.48%, PC2 = 18.15%, PC3 = 15.82%) explained 56.45% of the total variation. Heat map analysis using Ward clustering revealed cultivar groupings based on traits like nutrient content and fatty acid composition.

CONCLUSIONS

The findings obtained in this study allow producers to select the most suitable cultivars for obtaining more efficient and high-quality products. Additionally, choosing cultivars based on environmental factors and market demands contributes to the development of more effective production strategies. The ultimate goal is to provide insights that guide the selection of pistachio cultivars optimized for both agricultural sustainability and market-specific requirements.

Mechanism of Transcription Factor ChbZIP1 Enhanced Alkaline Stress Tolerance in Chlamydomonas reinhardtii

Alkaline environments such as alkaline lands, lakes, and industrial wastewater are not conducive to the growth of plants and microorganisms due to high pH and salinity. ChbZIP1 is a bZIP family transcription factor isolated from an alkaliphilic microalgae (Chlorella sp. BLD). Previous studies have demonstrated its ability to enhance alkaline tolerance in Arabidopsis thaliana. However, the potential of ChbZIP1 to confer similar alkaline tolerance in other microalgae remains unclear, and the specific mechanisms are not fully understood. The analysis of cellular physiological and biochemical indicators revealed that the ChbZIP1 transformants exhibited enhanced photosynthetic activity, increased lipid accumulation, and reduced fatty acid unsaturation. Genes associated with cellular reactive oxygen species (ROS) detoxification were found to be upregulated, and a corresponding increase in antioxidant enzyme activity was detected. In addition, the relative abundance of intracellular ROS and malondialdehyde (MDA) was significantly lower in the transformants. In summary, our research indicates that ChbZIP1 enhances the tolerance of Chlamydomonas reinhardtii to alkaline environments through several mechanisms, including the repair of damaged photosynthesis, increased lipid accumulation, improved fatty acid unsaturation, and enhanced antioxidant enzyme activity. This study aims to contribute to a more comprehensive understanding of the mechanisms underlying alkalinity tolerance in microalgae and offers new insights and theoretical foundations for the utilization of microalgae in alkaline environments.

Foliar Application of Zinc Oxide Nanoparticles Alleviates Phenanthrene and Cadmium-Induced Phytotoxicity in Lettuce: Regulation of Plant-Rhizosphere-Microbial Long Distance

Foliar application of beneficial nanoparticles exhibits potential in mitigating combined stresses from heavy metals and polycyclic aromatic hydrocarbons (PAHs) in crops, necessitating a comprehensive understanding of plant-rhizosphere-microbial processes to promote sustainable nanotechnology in agriculture. Herein, we investigated the mitigating mechanisms of foliar application of zinc oxide nanoparticles (nZnO) on lettuce growth under phenanthrene (Phe) and cadmium (Cd) costress. Compared to Phe + Cd treatment, low (L-nZnO) and high (H-nZnO) concentration of nZnO increased fresh biomass (27.2% and 8.42%) and root length (20.4% and 39.6%) and decreased MDA (35.0% and 40.0%) and H2O2 (29.0% and 15.6%) levels. L-nZnO and H-nZnO decreased Cd in roots (26.8% and 41.8%) and enhanced Zn in roots (19.9% and 107%), stems (221% and 2510%), and leaves (233% and 1500%), suggesting the long-distance migration of Zn from leaves to roots and subsequently regulating the metabolic pathways and microbial communities. Metabolomics revealed that nZnO modulated leaf glycerophospholipid metabolism and amino acid pathways and promoted rhizosphere soil carbon and phosphorus metabolism. Additionally, nZnO enriched the plant-growth-promoting, extreme, and stress-resistant bacteria in roots and leaves and heavy-metal-resistant and PAH-degrading bacteria in rhizosphere soil. These findings underscore the promising nanostrategy of nZnO to benefit plant growth in soil cocontaminated with heavy metals and PAHs.

Enhancing Food Security via selecting Superior Camelina (Camelina sativa L.) parents: a positive approach incorporating pheno-morphological traits, fatty acids composition, and Tocopherols Content

BACKGROUND

Preserving plant genetic resources is essential for tackling global food security challenges. Effectively meeting future agricultural demands requires comprehensive and efficient assessments of genetic diversity in breeding programs and germplasm from gene banks. This research investigated the diversity of pheno-morphological traits, along with the fatty acid and tocopherol content and composition, in 135 double haploid lines of camelina.

RESULTS

The number of sub-branches, siliques number of main-branch and sub-branch, and seeds number in siliques of the main-branch displayed notable coefficients of variation with values of 33.19%, 30.32%, 29.23%, and 23.81% respectively. Within the current investigation, the measurements of height, sub-branch number, and thousand seed weight varied from 53.50 to 86.50 cm, 3.50 to 14, and 0.73 to 1.52 g, respectively. The analysis unveiled that the average content of omega-3, omega-6, and omega-9 fatty acids in the examined lines was approximately 33%, 20%, and 17%, respectively. The total tocopherol content varied between 675 and 877 ppm, predominantly consisting of gamma-tocopherol, which accounted for over 95% of the total content. The fatty acid C18:2 displayed a markedly strong positive correlation with alpha-tocopherol (0.99**), while C18:3 exhibited positive correlations with gamma-tocopherol (0.98**) and total tocopherol (0.98**). Furthermore, a positive correlation was evident between C20:1 and delta-tocopherol (0.98**). The scrutinized lines, specifically lines 35, 72, 94, and 126 demonstrated notable attributes regarding yield and yield components. Conversely, in the realm of biochemical traits, lines 35, 66, 47, 30, 65, 135, 83, 27, 4, 77, 62, 81, and 93 stood out for their elevated potential. The gene expression analysis related to the tocopherol biosynthesis pathway revealed distinct expression patterns. Specifically, the VTE1 gene exhibited the highest level of expression. In contrast, the VTE3 gene displayed the lowest level of expression compared to other genes.

CONCLUSIONS

The study's findings hold great potential for improving food security by enabling the selection of superior camelina parent plants based on specific traits. This approach can drive the development of high-yielding varieties with enhanced nutritional value and better-quality camelina oil.

The Genetics and Breeding of Heat Stress Tolerance in Wheat: Advances and Prospects

Heat stress is one of the major concerns for wheat production worldwide. Morphological parameters such as germination, leaf area, shoot, and root growth are affected by heat stress, with affected physiological parameters including photosynthesis, respiration, and water relation. Heat stress also leads to the generation of reactive oxygen species that disrupt the membrane systems of thylakoids, chloroplasts, and the plasma membrane. The deactivation of the photosystems, reduction in photosynthesis, and inactivation of Rubisco affect the production of photo-assimilates and their allocation, consequently resulting in reduced grain yield and quality. The development of thermo-tolerant wheat varieties is the most efficient and fundamental approach for coping with global warming. This review provides a comprehensive overview of various aspects related to heat stress tolerance in wheat, including damages caused by heat stress, mechanisms of heat stress tolerance, genes or QTLs regulating heat stress tolerance, and the methodologies of breeding wheat cultivars with high heat stress tolerance. Such insights are essential for developing thermo-tolerant wheat cultivars with high yield potential in response to an increasingly warmer environment.

Analysis of the MYB gene family in tartary buckwheat and functional investigation of FtPinG0005108900.01 in response to drought

Tartary buckwheat (Fagopyrum tataricum) is an important crop used for edible food and medicinal usage. Drought annually brings reduction in crop yield and quality, causing enormous economic losses. Transcription factors are often involved in the regulation of plant responses to environmental stresses. In this study, we identified 233 MYB transcription factors in tartary buckwheat and classified them into 13 groups, including 1R, R2R3, 3R, 4R types. Gene structure and conserved motifs of these 233 FtMYBs suggested the relative conservation of these FtMYBs within each group. There is strong collinearity within the genomes of F. tataricum, with identifying syntenic gene pairs of FtMYB. Further, the expansion of FtMYB genes was attributed to whole genome duplication. The enrichment analysis of cis-acting elements in the FtMYB genes indicated that FtMYBs may participate in abiotic stress responses. The transcriptional changes of FtMYB genes in tartary buckwheat were then investigated using public data and qPCR. A number of FtMYB genes exhibited apparent transcript levels in the detected tissues and most of them disturbed their expression after the treatment of PEG6000 or natural treatment of tartary buckwheat seedlings. Some of the FtMYB genes showed a similar expression trend with qPCR validation. FtMYB gene FtPinG0005108900.01 were shown to activated by PEG6000 and natural drought treatment, and its encoded protein localizes to nucleus, revealing it as a typical transcription factor. Overexpression of FtPinG0005108900.01 increase the drought tolerance, and transcriptome analysis indicated that lignin synthesis other than flavonoid biosynthesis pathway was activated in the overexpressing plants following drought treatment. Our results provided detailed evolution and comparative genomic information of FtMYBs in tartary buckwheat and dissected the function of a FtMYB gene FtPinG0005108900.01 in response to drought.

Metabolomics-based profiling of five Salvia L. (Lamiaceae) species using untargeted data analysis workflow

INTRODUCTION

The genus Salvia L., a member of the family Lamiaceae, is a keystone genus with a wide range of medicinal properties. It possesses a rich metabolite source that has long been used to treat different disorders.

OBJECTIVES

Due to a deficiency of untargeted metabolomic profiling in the genus Salvia, this work attempts to investigate a comprehensive mass spectral library matching, computational data annotations, exclusive biomarkers, specific chemotypes, intraspecific metabolite profile variation, and metabolite enrichment by a case study of five medicinal species of Salvia.

MATERIAL AND METHODS

Aerial parts of each species were subjected to QTRAP liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis workflow based on untargeted metabolites. A comprehensive and multivariate analysis was acquired on the metabolite dataset utilizing MetaboAnalyst 6.0 and the Global Natural Products Social Molecular Networking (GNPS) Web Platform.

RESULTS

The untargeted approach empowered the identification of 117 metabolites by library matching and 92 nodes annotated by automated matching. A machine learning algorithm as substructural topic modeling, MS2LDA, was further implemented to explore the metabolite substructures, resulting in four Mass2Motifs. The automated library newly discovered a total of 23 metabolites. In addition, 87 verified biomarkers of library matching, 58 biomarkers of GNPS annotations, and 11 specific chemotypes were screened.

CONCLUSION

Integrative spectral library matching and automated annotation by the GNPS platform provide comprehensive metabolite profiling through a workflow. In addition, QTRAP LC-MS/MS with multivariate analysis unveiled reliable information about inter and intraspecific levels of differentiation. The rigorous investigation of metabolite profiling presents a large-scale overview and new insights for chemotaxonomy and pharmaceutical studies.

Lipid Profile of Larix cajanderi Mayr in Adaptation to Natural Conditions in the Cryolithozone

The prevalence of coniferous trees in the forest landscapes of northeastern Siberia is conditioned by their high frost resistance. The Kajander larch (Larix cajanderi Mayr), which can survive under natural conditions (down to -60 °C) in the cryolithozone of Yakutia, is the dominant forest-forming species. We hypothesise that our study using HPTLC-UV/Vis/FLD, TLC-GC/FID, and GC-MS methods of seasonal features of the lipid profile of Kajander larch tissues will bring us closer to understanding the mechanisms of participation of lipid components in the adaptation of this valuable tree species to the cold climate of the cryolithozone. Rare delta5-unsaturated polymethylene-interrupted fatty acids (∆5-UPIFA) were identified in the fatty acids (FAs) of L. cajanderi shoots, including 18:2(Δ5.9) (taxoleic), 18:3(Δ5.9.12) (pinolenic), and 18:4(Δ5.9.12.15) (coniferonic). It was found that the content of ∆5-UPIFA in L. cajanderi shoots markedly increased (1.5-fold, representing up to 23.9% of sum FAs) during the autumnal transition of trees to dormancy. It was observed that the ranges of low temperatures experienced during the prolonged winter period primarily determined the structural diversity of membrane lipids and their constituent FAs during the cold adaptation of L. cajanderi. The results obtained can be used for the selection of molecular markers of cold tolerance in woody plants, including fruit trees.

Plant growth-promoting Bacillus amyloliquefaciens orchestrate homeostasis under nutrient deficiency exacerbated drought and salinity stress in Oryza sativa L. seedlings

MAIN CONCLUSION

Nutrient deficiency intensifies drought and salinity stress on rice growth. Bacillus amyloliquefaciens inoculation provides resilience through modulation in metabolic and gene regulation to enhance growth, nutrient uptake, and stress tolerance. Soil nutrient deficiencies amplify the detrimental effects of abiotic stresses, such as drought and salinity, creating substantial challenges for overall plant health and crop productivity. Traditional methods for developing stress-resistant varieties are often slow and labor-intensive. Previously, we demonstrated that plant growth-promoting rhizobacteria Bacillus amyloliquefaciens strain SN13 effectively alleviates stress induced by sub-optimum nutrient conditions in rice. In this study, we evaluated the effectiveness of SN13 in reducing the compounded impacts of drought and salinity under varying nutrient regimes in rice seedlings. The results demonstrated that PGPR inoculation not only improved the growth parameters, nutrient content, and physio-biochemical characteristics under nutrient-limited conditions, but also reduced the oxidative stress markers. The altered expression of stress-related and transcription factor genes (USP, DEF, CYP450, GST, MYB, and bZIP) revealed the regulatory effect of PGPR in enhancing stress tolerance through these genes. GC-MS-based untargeted metabolomic analysis revealed that PGPR significantly influenced various metabolic pathways, including galactose metabolism, fructose and mannose metabolism, and fatty acid biosynthesis pathways, suggesting that PGPR affects both energy production and stress-protective mechanisms, facilitating better growth and survival of rice seedlings.

Transcriptomic and Metabolomic Analyses of the Piz-t-Mediated Resistance in Rice against Magnaporthe oryzae

Magnaporthe oryzae causes devastating rice blast disease, significantly impacting rice production in many countries. Among the many known resistance (R) genes, Piz-t confers broad-spectrum resistance to M. oryzae isolates and encodes a nucleotide-binding site leucine-rich repeat receptor (NLR). Although Piz-t-interacting proteins and those in the signal transduction pathway have been identified over the last decade, the Piz-t-mediated resistance has not been fully understood at the transcriptomic and metabolomic levels. In this study, we performed transcriptomic and metabolomic analyses in the Piz-t plants after inoculation with M. oryzae. The transcriptomic analysis identified a total of 15,571 differentially expressed genes (DEGs) from infected Piz-t and wild-type plants, with 2791 being Piz-t-specific. K-means clustering, GO term analysis, and KEGG enrichment pathway analyses of the total DEGs identified five groups of DEGs with distinct gene expression patterns at different time points post inoculation. GO term analysis of the 2791 Piz-t-specific DEGs revealed that pathways related to DNA organization, gene expression regulation, and cell division were highly enriched in the group, especially at early infection stages. The gene expression patterns in the transcriptomic datasets were well correlated with the metabolomic profiling. Broad-spectrum "pathway-level" metabolomic analyses indicated that terpenoid, phenylpropanoid, flavonoid, fatty acid, amino acid, glycolysis/TCA, and phenylalanine pathways were altered in the Piz-t plants after M. oryzae infection. This study offers new insights into the molecular dynamics of transcripts and metabolites in R-gene-mediated resistance against M. oryzae and provides candidates for enhancing rice blast resistance through the engineering of metabolic pathways.

Exploring the role of FAT genes in Solanaceae species through genome-wide analysis and genome editing

Plants produce numerous fatty acid derivatives, and some of these compounds have significant regulatory functions, such as governing effector-induced resistance, systemic resistance, and other defense pathways. This study systematically identified and characterized eight FAT genes (Acyl-acyl carrier protein thioesterases), four in the Solanum lycopersicum and four in the Solanum tuberosum genome. Phylogenetic analysis classified these genes into four distinct groups, exhibiting conserved domain structures across different plant species. Promoter analysis revealed various cis-acting elements, most of which are associated with stress responsiveness and growth and development. Micro-RNA (miRNA) analysis identified specific miRNAs, notably miRNA166, targeting different FAT genes in both species. Utilizing clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9)-mediated knockout, mutant lines for SlFATB1 and SlFATB3 were successfully generated and exhibited diverse mutation types. Biochemical evaluation of selected mutant lines revealed significant changes in fatty acid composition, with linoleic and linolenic acid content variations. The study also explored the impact of FAT gene knockout on tomato leaf architecture through scanning electron microscopy, providing insights into potential morphological alterations. Knocking out of FAT genes resulted in a significant reduction in both trichome and stoma density. These findings contribute to a comprehensive understanding of FAT genes in Solanaceous species, encompassing genetic, functional, and phenotypic aspects.

Assessment of physicochemical parameters, bioactive compounds, biological activities, and nutritional value of the most two commercialized pollen types of date palm (Phoenix dactylifera L.) in Morocco

The pollen of date palm (Phoenix dactylifera L.) is known for its nutritional value and implications as a health-promoting component. Due to its low cost, date palm pollen crushed with its spadix is more widely commercialized and used in Morocco than pure date palm pollen free of spadix. Thus, this study aimed to assess the physicochemical and phytochemical parameters, biological activities, and nutritional value of the two pollen types: Pure date palm pollen and date palm pollen crushed with its spadix. Various physicochemical parameters were determined, including humidity, water activity (aw), total soluble solids, ash content, and color parameters (L*, a*, b*, C*ab, and hab). Additionally, the phenolic compound profiles were analyzed, and the in vitro antioxidant, enzyme inhibitory, and antidiabetic activities were assessed for both pure date palm pollen and date palm pollen crushed with its spadix. Furthermore, the nutritional value was evaluated by determining protein and carbohydrate contents, and mineral and fatty acid profiles. The results have revealed that pure date palm pollen had higher humidity, aw, L*, and hab color parameters than date palm pollen crushed with its spadix, but lower total soluble solid and ash contents. The main phenolic compounds in pure date palm pollen were ellagic acid, rutin, fisetin, and quercetin, whereas date palm pollen crushed with its spadix contained mainly catechin, chlorogenic acid, p-coumaric acid, ferulic acid, and rutin. Moreover, pure date palm pollen showed greater in vitro antioxidant activity, while date palm pollen crushed with its spadix had higher enzyme inhibitory and antidiabetic activities. PDPS was the richest source of proteins, carbohydrates, minerals, and saturated fatty acids, while date palm pollen crushed with its spadix was a better source of unsaturated fatty acids, which are mainly represented by linoleic acid. In conclusion, although date palm pollen crushed with its spadix is the most widely consumed type, its nutritional value is lower than that of pure date palm pollen. Thus, pure date palm pollen could potentially serve as a better source of many bioactive compounds, making it a viable supplement for various health applications.

Ectopic expression of HvbHLH132 from hulless barley reduces cold tolerance in transgenic Arabidopsis thaliana

KEY MESSAGE

Overexpression of HvbHLH132 from hulless barley impairs in chilling and freezing tolerance at the seedlings stage in Arabidopsis thaliana The basic helix-loop-helix (bHLH) transcription factors (TF) are ubiquitously existed in eukaryote and play crucial roles in numerous biological processes. However, the characterization of their members and functions in hulless barley remains limited. Here, we conducted a genome-wide identification of the HvbHLH gene family and assessed the role of HvbHLH132 in cold stress tolerance. We identified 141 HvbHLH genes, which were categorized into twelve subfamilies. Subcellular localization predictions indicated that the majority of HvbHLH proteins were localized in the nucleus. cis-Acting element analysis revealed that the promoter regions of the HvbHLH family contain diverse elements associated with various biological processes. Expression profiling of the 141 HvbHLH genes in two extreme varieties revealed that HvbHLH132 was significantly induced and exhibited substantial differential expression under cold stress. Analyses of subcellular localization and transactivation activity confirmed that HvbHLH132 specifically localized in the nucleus and contributed to transcriptional activation. Furthermore, overexpression of HvbHLH132 in Arabidopsis resulted in impaired chilling and freezing tolerance at the seedling stage, leading to biochemical changes unfavorable for freezing stress. Additionally, the expression of some cold-responsive genes (COR) genes was significantly less induced compared to wild type under freezing stress. This study provides comprehensive insight into the HvbHLH gene family and reveals a critical role of HvbHLH132 in regulating cold tolerance in plants.

Development of an HPPD-Inhibitor Resistant Wheat and Multiomics Integrative Analysis of Herbicide Toxicity and OsHIS1 Detoxification in Wheat

Weed infestation in agricultural fields significantly diminishes crop yields. Herbicides are widely used as a primary method of weed control. Developing herbicide-resistant crops through the expression of resistant genes represents a sustainable approach. This study generated wheat germplasms highly resistant to 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides by transforming the rice HPPD INHIBITOR SENSITIVE 1 (OsHIS1) gene into Xinong 511, conferring resistance to mesotrione at levels up to nine times the typical field application rate (1350 g ai ha-1). Agronomic trait evaluations under greenhouse and field conditions showed no additional effects on wheat. Herbicide susceptibility assays confirmed the specific resistance to different HPPD inhibitors. Transcriptome and metabolome analyses revealed regulation of flavonoid and photosynthesis-antenna protein pathways in the herbicide functional. Collectively, OsHIS1 could be applied in the production of herbicide-resistant wheat.

Exploring the response of yellow lupine (Lupinus luteus L.) root to drought mediated by pathways related to phytohormones, lipid, and redox homeostasis

BACKGROUND

Yellow lupine (Lupinus luteus L.) is a high-protein crop of considerable economic and ecological significance. It has the ability to fix atmospheric nitrogen in symbiosis with Rhizobium, enriching marginal soils with this essential nutrient and reducing the need for artificial fertilizers. Additionally, lupine produces seeds with a high protein content, making it valuable for animal feed production. However, drought negatively affects lupine development, its mutualistic relationship with bacteria, and overall yield. To understand how lupine responds to this stress, global transcriptome sequencing was conducted, along with in-depth biochemical, chromatography, and microscopy analyses of roots subjected to drought. The results presented here contribute to strategies aimed at mitigating the effects of water deficit on lupine growth and development.

RESULTS

Based on RNA-seq, drought-specific genes were identified and annotated to biological pathways involved in phytohormone biosynthesis/signaling, lipid metabolism, and redox homeostasis. Our findings indicate that drought-induced disruption of redox balance characterized by the upregulation of reactive oxygen species (ROS) scavenging enzymes, coincided with the accumulation of lipid-metabolizing enzymes, such as phospholipase D (PLD) and lipoxygenase (LOX). This disruption also led to modifications in lipid homeostasis, including increased levels of triacylglycerols (TAG) and free fatty acids (FFA), along with a decrease in polar lipid content. Additionally, the stress response involved alterations in the transcriptional regulation of the linolenic acid metabolism network, resulting in changes in the composition of fatty acids containing 18 carbons.

CONCLUSION

The first comprehensive global transcriptomic profiles of lupine roots, combined with the identification of key stress-responsive molecules, represent a significant advancement in understanding lupine's responses to abiotic stress. The increased expression of the Δ12DESATURASE gene and enhanced PLD activity lead to higher level of linoleic acid (18:2), which is subsequently oxidized by LOX, resulting in membrane damage and malondialdehyde (MDA) accumulation. Oxidative stress elevates the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT), while the conversion of FFAs into TAGs provides protection against ROS. This research offers valuable molecular and biochemical candidates with significant potential to enhance drought tolerance . It enables innovative strategies in lupine breeding and crop improvement to address critical agricultural challenges.

Physiological and metabolic responses of Sophora tonkinensis to cadmium stress

Sophora tonkinensis is a significant medicinal plant indigenous to China and Vietnam. In China, S. tonkinensis is mainly grown naturally on limestone mountains or is cultivated artificially in arable land. Heavy metal contamination in agricultural soil, particularly cadmium (Cd), poses serious threats to soil health, as well as the growth and productivity of S. tonkinensis. However, information regarding the physiological and metabolic mechanism of S. tonkinensis under Cd toxicity conditions remains limited. In this study, a hydroponic experiment was conducted to investigate the physiological and metabolic responses of S. tonkinensis to varying concentrations of Cd (0, 20, 40, 60, 80 μM), designated as T0, T1, T2, T3, and T4 respectively. The results indicated that the Cd stress significantly impaired the growth and physiological activity of S. tonkinensis. Specifically, reductions were observed in plant height (15.3% to 37.1%) along with shoot fresh weight (9.6% to 36.3%), shoot dry weight (8.2% to 34.1%), root fresh weight (6.7% to 38.2%) and root dry weight (5.1% to 51.3%). This impairment was attributed to a higher uptake and accumulation of Cd in the roots. The decrease in growth was closely linked to the increased production of reactive oxygen species (ROS), which led to cellular damage under Cd toxicity; however, increased antioxidant enzyme activities improved the stress tolerance of S. tonkinensis's stress to Cd toxicity. Non-targeted metabolomic analyses identified 380 differential metabolites (DMs) in the roots of S. tonkinensis subjected to varying level of Cd stress, including amino acids, organic acids, fatty acids, ketones, and others compounds. Further KEGG pathway enrichment analysis revealed that several pathways, such as ABC transporters, isoflavonoid biosynthesis, and pyrimidine metabolism were involved in the response to Cd. Notably, the isoflavonoid biosynthesis pathway was significantly enriched in both T0 vs. T2 and T0 vs. the higher level (80 μM) of Cd stress, highlighting its significance in the plant responses to Cd stress. In conclusion, the identification of key pathways and metabolites is crucial for understanding Cd stress tolerance in S. tonkinensis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12298-024-01522-w.

Omics exploration of Tetraselmis chuii adaptations to diverse light regimes

Microalgae are significantly influenced by light quality and quantity, whether in their natural habitats or under laboratory and industrial culture conditions. The present study examines the adaptive responses of the marine microalga Tetraselmis chuii to different light regimes, using a cost-effective filtering method and a multi-omics approach. Microalgal growth rates were negatively affected by all filtered light regimes. After six days of cultivation, growth rate for cultures exposed to blue and green filtered light was 67%, while for red filter was 83%, compared to control cultures. Transcriptomic analysis revealed that the usage of green filters resulted in upregulation of transcripts involved in ribosome biogenesis or coding for elongation factors, exemplified by a 2.3-fold increase of TEF3. On the other hand, a 2.7-fold downregulation was observed in photosynthesis-related petJ. Exposure to blue filtered light led to the upregulation of transcripts associated with pyruvate metabolism, while photosynthesis was negatively impacted. In contrast, application of red filter induced minor transcriptomic alterations. Regarding metabolomic analysis, sugars, amino acids, and organic acids exhibited significant changes under different light regimes. For instance, under blue filtered light sucrose accumulated over 6-fold, while aspartic acid content decreased by 4.3-fold. Lipidomics analysis showed significant accumulation of heptadecanoic and linoleic acids under green and red light filters. Together, our findings indicate that filter light can be used for targeted metabolic manipulation.

Chemical characterization, pathway enrichments and bioactive potentials of catechin-producing endophytic fungi isolated from tea leaves

Endophytes acquire flavonoid biosynthetic genes from the host medicinal plants. Despite tea (Camellia sinensis (L.) Kuntze) being the major source of bioactive catechins, catechin-producing endophytic fungi have never been reported from the tea plant. Here, we report the isolation and characterization of catechin-producing endophytic fungi isolated from tea leaves, their chemical characterization, and associated bioactivities. Among the nine isolated endophytes, two (CSPL6 and CSPL5b) produced catechin (381.48 and 166.40 μg per mg extract) and epigallocatechin-o-gallate (EGCG; 484.41 and 281.99 μg per mg extract) as quantified by high-performance liquid chromatography (HPLC). The isolates were identified as Pseudopestalotiopsis camelliae-sinensis and Didymella sinensis based on molecular and morphological characterization. Untargeted metabolomics using gas-chromatography mass spectroscopy (GCMS) revealed the presence of several bioactive phytochemicals mostly belonging to tyrosols, pyridoxines, fatty acids, aminopyrimidine, and benzenetriol classes. Metabolic pathways pertaining to the biosynthesis of unsaturated fatty acids (UFAs), butanoate metabolism, and linoleic acid metabolism were highly enriched in both catechin-producing isolates. The isolates were able to differentially scavenge intracellular O2 and N2 free-radicals, but CSPL5b demonstrated relatively superior bioactivities compared to CSPL6. Both isolates stimulated the growth of various probiotic strains, indicating prebiotic effects that are otherwise known to be associated with catechins. Collectively, the current study demonstrated that fungal endophytes CSPL6 and CSPL5b, isolated from tea leaves, could be used as alternative sources of catechins, and hold promising potential in evidence-based therapeutics.