Increase In Carotenoid Content Research Articles

The Alteration in Physiological Status, Growth and Essential Oil Profile of French Marigold (Tagetes patula L.) Owing to Seaweed Extract and Salicylic Acid Application

Abstract Purpose Medicinal plants show a relevant importance in human life and health. The use of natural substances in crop management is not only significant for the plant healthy growth and yield, but also for obtaining safe products. The study aimed to examine the effect of seaweed extract (SW) as a natural source of nutrition and salicylic acid (SA) on plant health, physiology and essential oil profile of French marigold (Tagetes patula L.). Methods Three levels of salicylic acid, SA50, SA100 and SA200, (50, 100, and 200 mg L− 1) and three levels of seaweed extract, SW2, SW4 and SW6 (2.0, 4.0, and 6.0 ml L− 1), in comparison with control treatment (tap water) were applied as foliar sprayings. The seven treatments were arranged in randomized complete block design and were replicated thrice in two growing seasons (2020 and 2021). Results Findings pointed out that SA200 increased plant height, branches number plant− 1, stem diameter, leaf area, leaves number plant− 1, plant fresh weight, and plant dry weight by 32.9, 112.2, 59.2, 34.4, 44.3, 33.0 and 56.9% (averages of the two seasons), respectively, compared to the control treatment (tap water). SW6 increased carotenoids content by 34.8 and 46.4% in 2020 and 2021 seasons, respectively. Salicylic acid at the rate of 200 mg L− 1 along seaweed extract at 6 ml L− 1 gave the highest values of total sugars and free amino acids. SA200 alone recorded the maximal value of peroxidase activity surpassing the other treatments. SW6 possessed the greatest essential oil content in both seasons, statistically equaling SA200 in the first season. Huge variations in essential oil profile were recorded under the tested trial treatments. Conclusion It could be concluded that salicylic acid and seaweed extract foliar application unveiled their involvement in diverse physiological and developmental responses; pigment formation, enzyme activities, flower induction, nutrient uptake, essential oil metabolism, and overall plant growth and development. It is recommended to use the highest concentrations of the tested substances (SA at 200 mg L− 1 or SW at 6.0 ml L− 1) for achieving distinctive improvements in physiological responses of French marigold plant.

Carotenoid biosynthesis genes LcLCYB, LcLCYE, and LcBCH from wolfberry confer increased carotenoid content and improved salt tolerance in tobacco

Carotenoids play essential roles in plant growth and development and provide plants with a tolerance to a series of abiotic stresses. In this study, the function and biological significance of lycopene β-cyclase, lycopene ε-cyclase, and β-carotene hydroxylase, which are responsible for the modification of the tetraterpene skeleton procedure, were isolated from Lycium chinense and analyzed. The overexpression of lycopene β-cyclase, lycopene ε-cyclase, and β-carotene hydroxylase promoted the accumulation of total carotenoids and photosynthesis enhancement, reactive oxygen species scavenging activity, and proline content of tobacco seedlings after exposure to the salt stress. Furthermore, the expression of the carotenoid biosynthesis genes and stress-related genes (ascorbate peroxidase, catalase, peroxidase, superoxide dismutase, and pyrroline-5-carboxylate reductase) were detected and showed increased gene expression level, which were strongly associated with the carotenoid content and reactive oxygen species scavenging activity. After exposure to salt stress, the endogenous abscisic acid content was significantly increased and much higher than those in control plants. This research contributes to the development of new breeding aimed at obtaining stronger salt tolerance plants with increased total carotenoids and vitamin A content.

Elevated osmolytes accumulation helps in combating NaCl stress causing negative impacts on growth and metabolism of Vigna radiata (L.)

Salinity stress is one of the main abiotic stresses that have a negative impact on the growth performance of green gram. The current study was carried out as a result to find out growth, and morpho-biochemical changes in Vigna radiata CO7 variety cultivated under NaCl stress treatments. The V. radiata CO7 variety was selected and the experiment was carried out in pot culture under varying NaCl concentrations viz., 0, 50, 75, 100, and 125 mM respectively to assess maximum tolerance range of the CO7 variety. The salt stress was given on 15th days after sowing and sampling was done after 10 days of treatment on the 25th, 35th, and 45th day respectively. Salt stress results in a steep decline in shoot length, biomass, chlorophyll contents a and b, and soluble protein contents with increased NaCl treatments on all sampling days. However, carotenoid contents, and compatible solutes including proline, Glycine-betaine, Amino acids and total soluble sugars contents were found to be upregulated under varying NaCl concentrations in V. radiata CO7 variety on all sampling days. Thus, increased carotenoid contents, and osmolytes, provide stress tolerance to V. radiata CO7 variety by maintaining the turgor pressure of cells and preventing further water loss under varying NaCl concentrations. Hence, this variety shows maximum surveillance at 75 mM and beyond this plant performance is restricted and further study is needed to access CO7 variety for a breeding program to enhance salt stress tolerance.

Foliar-applied silicate potassium modulates growth, phytochemical, and physiological traits in Cichorium intybus L. under salinity stress

One of the major problems endangering plant growth and productivity worldwide is salt stress. This study aimed to assess the effects of potassium silicate (K2O3Si) on the physical, biochemical, and morphological characteristics of chicory (Cichorium intybus L.) under various levels of salinity stress. The plants were treated with K2O3Si at concentrations of 0, 1, 2, and 3 mM and cultivated under different salt stress conditions (0, 80, 160, and 240 mM NaCl). The findings revealed that salt stress led to decreased root and shoot dry weights, Fv/Fm ratio, chlorophyll a, b, and total chlorophyll, as well as inulin contents. However, foliar exposure to K2O3Si at all salinity levels resulted in improvements in the measured traits. As salinity levels increased, there was a corresponding increase in the accumulation of sodium ions (Na+) and a sharp reduction in potassium ions (K +) in the shoot. Nonetheless, treatment with K2O3Si caused a decrease in Na + accumulation and an improvement in K+ content under all salinity levels. Carotenoid content increased under 80 mM salinity stress, but decreased with higher salinity levels. Application of K2O3Si at all levels resulted in increased carotenoid content under salinity stress conditions. The content of MDA increased significantly with increasing salinity stress, particularly at 240 mM. However, foliar spraying with K2O3Si significantly decreased MDA content at all salinity levels. Salinity stress up to 160 mM increased the total phenol, flavonoid, and anthocyanin contents, while 240 mM NaCl decreased the biosynthesis of phytochemicals. Additionally, the use of K2O3Si increased the content of total phenol, flavonoid, and anthocyanin at all salt levels. Foliar application of K2O3Si increased the tolerance of chicory plants to salinity stress by reducing MDA and increasing phenolic compounds and potassium content. These results suggest that exogenous K2O3Si can be a practical strategy to improve the growth and yield of chicory plants exposed to saline environments.

Exogenous leucine delayed the yellowing of postharvest broccoli by regulating strigolactone and abscisic acid signals based on multi-omics profiling

The yellowing of postharvest broccoli is the immediate manifestation of its quality deterioration, which can cause the loss of commodity value. This study employs a comprehensive analysis integrating transcriptomics and metabolomics to elucidate the effects and potential molecular mechanisms of exogenous leucine on pigment metabolism in postharvest broccoli stored at 10 ± 0.5 °C. Results demonstrate that leucine treatment significantly inhibited the decrease of chlorophyll content and the increase of carotenoid content. Leucine treatment also inhibited the respiration rate and maintained higher vitamin C content, total phenols content and DPPH radical scavenging activity of broccoli. Leucine treatment promoted chlorophyll biosynthesis by up-regulating UROD, PPOX, MC, CHLM, POR, DCVR, MT, and CAS expression while inhibiting chlorophyll liberation and degradation by up-regulating CABs expression and down-regulating NYC1, CLH2, PAO, and PPD expression. Additionally, exogenous leucine alleviated the damage of photosystem I, photosystem II, and photosynthetic electron transport chains in the thylakoid membrane. Furthermore, leucine treatment results in a lower transcriptional level of PDS, LCYB, crtZ, and ZEP, leading to reduced lycopene, zeaxanthin, and β-carotene content. Leucine treatment promotes the biosynthesis of carlactone, a strigolactone (SL) precursor, by up-regulating DWARF27, CCD7, and CCD8 expression. Additionally, leucine treatment down-regulated XDH expression and up-regulated CYP707A expression, inhibiting the biosynthesis and accumulation of abscisic acid (ABA). Consequently, our findings suggest that ABA and SLs may serve as crucial signaling factors in regulating chlorophyll and carotenoid metabolism in leucine-treated broccoli. This study introduces a novel method with theoretical support for delaying the yellowing process in postharvest broccoli.

BnaABF3 and BnaMYB44 regulate the transcription of zeaxanthin epoxidase genes in carotenoid and abscisic acid biosynthesis.

Zeaxanthin epoxidase (ZEP) is a key enzyme that catalyzes the conversion of zeaxanthin to violaxanthin in the carotenoid and abscisic acid (ABA) biosynthesis pathways. The rapeseed (Brassica napus) genome has 4 ZEP (BnaZEP) copies that are suspected to have undergone subfunctionalization, yet the 4 genes' underlying regulatory mechanisms remain unknown. Here, we genetically confirmed the functional divergence of the gene pairs BnaA09.ZEP/BnaC09.ZEP and BnaA07.ZEP/BnaC07.ZEP, which encode enzymes with tissue-specific roles in carotenoid and ABA biosynthesis in flowers and leaves, respectively. Molecular and transgenic experiments demonstrated that each BnaZEP pair is transcriptionally regulated via ABA-responsive element-binding factor 3 s (BnaABF3s) and BnaMYB44s as common and specific regulators, respectively. BnaABF3s directly bound to the promoters of all 4 BnaZEPs and activated their transcription, with overexpression of individual BnaABF3s inducing BnaZEP expression and ABA accumulation under drought stress. Conversely, loss of BnaABF3s function resulted in lower expression of several genes functioning in carotenoid and ABA metabolism and compromised drought tolerance. BnaMYB44s specifically targeted and repressed the expression of BnaA09.ZEP/BnaC09.ZEP but not BnaA07.ZEP/BnaC07.ZEP. Overexpression of BnaA07.MYB44 resulted in increased carotenoid content and an altered carotenoid profile in petals. Additionally, RNA-seq analysis indicated that BnaMYB44s functions as a repressor in phenylpropanoid and flavonoid biosynthesis. These findings provide clear evidence for the subfunctionalization of duplicated genes and contribute to our understanding of the complex regulatory network involved in carotenoid and ABA biosynthesis in B. napus.

Transcript Analysis Reveals Positive Regulation of CA12g04950 on Carotenoids of Pigment Pepper Fruit under Nitrogen Reduction

This study investigates the relationship between nitrogen fertilization and pepper fruit color by employing five different nitrogen treatments (N1: 750 kg/hm2, N2: 562.5 kg/hm2, N3: 375 kg/hm2, N4: 187.5, and N0: 0 kg/hm2). Fruits were harvested at 30 (S1: green ripening stage), 45 (S2: color transition stage), and 60 days (S3: red ripening stage) after flowering. Subsequently, pigment content, carotenoid component content, carotenoid enzyme activity, and transcriptome sequence were analyzed, and CA12g04950 function was validated through virus-induced gene silencing (VIGS). The results indicate that a reduction in nitrogen application led to an earlier onset of fruit color breakdown, and increased the contents of total carotenoid, capsanthin, phytoene and PSY (phytoene synthase) activity, LCYB (lycopene β-cyclase) activity and CCS (capsanthin/capsorubin synthase) activity. The analysis of different expression genes indicated that the most differently expressed genes were enriched in the N1 vs. N4 comparison, with 18 genes involved in carotenoid metabolism and 16 genes involved in nitrogen metabolism. Most DE genes were enriched in the pathways of photosynthesis, porphyrin, carotenoid biosynthesis, seleno-compounds, and nitrogen metabolism. There were numerous differential transcription factor families, including ERF, bHLH, MYB, C2H2, and NAC. Pearson correlation analysis revealed a significant positive correlation between CA12g04950 expression and 11 carotenoid genes in the N4 treatment. Subsequent silencing of CA12g04950 using VIGS resulted in delayed color ripening while a significant decrease in total carotenoid content and the expression levels of carotenoid genes. In conclusion, nitrogen reduction led to an increase in carotenoid content in pigment pepper fruits. Furthermore, under nitrogen reduction, CA12g04950 positively influenced the redness of the fruits.

Influence of Pasteurisation (Conventional vs. Radiofrequency) and Chill Storage on Retention of Ascorbic Acid, Tocopherol and Carotenoids in Salmorejo.

Salmorejo, a Mediterranean tomato-oil puree, is considered a dietary source of antioxidant vitamins C and E and carotenoids lycopene and β-carotene, the latter endowed with provitamin A activity. However, these antioxidants can be degraded in oxidation reactions catalysed or not by enzymes during pasteurisation and storage treatments used to stabilise the salmorejo before consumption. Due to its better penetration, the use of dielectric heating by radiofrequency (RF) may improve results of pasteurisation in this product. The objective was to assess the effects of pasteurisation temperature (70-100 °C, at 5 °C intervals) and storage time (0-5 months, at one-month intervals) on levels of ascorbic acid, α-tocopherol and carotenoids and antioxidant capacity (AC) in salmorejo pasteurised (over 10 s) by conventional (CH) or RF continuous heating. Two successive experiments were conducted to select an adequate pasteurisation temperature for use in the shelf-life study. Pasteurisation upon tested conditions allows a good retention of salmorejo antioxidants. Either CH or RF pasteurisers can be used with similar results. Vitamin C (L-ascorbic + dehydroascorbic acids) was more abundant (15-19 mg 100 g-1) than carotenoids (0.9-2.6 mg 100 g-1) (all-trans + cis lycopene and β-carotene) and α-tocopherol (0.8-1.2 mg 100 g-1) in the pasteurised product. Using excessively low temperatures (70 °C) resulted in partial losses of the three antioxidants, possibly due to oxidase residual activities. Intensifying thermal treatment improved this issue with minor losses of the thermolabile vitamin C and increased carotenoid content. Using a suitable temperature (80 °C) did not prevent most vitamin C from being degraded by the first month, while α-tocopherol, and, to a lesser extent, carotenoids, showed good retention levels during shelf life under refrigeration. Vitamins C and E and carotenoids, either by degradation, regeneration or releasing, likely contribute to the AC in salmorejo. Phenolic antioxidant response, radical-scavenging activities and redox potential values confirmed this finding. The pasteurised-chilled salmorejo shows good antioxidant properties with potential health implications, a positive nutritional aspect for consumers of this tomato-oil homogenate. The losses of antioxidants and AC due to pasteurization would be of little relevance compared to the losses accumulated during shelf life.

Qualidade química e compostos bioativos de batata-doce sob adubação fosfatada

ABSTRACT Sweet potato is among the most important food crops in the world. Due to its high genetic diversity, this species has cultivars that can respond in different ways depending on mineral fertilization. Among the nutrients, phosphorus is related to physiological and biochemical processes that can influence the final quality of the product. This study aimed to assess the influence of P doses on the quality and bioactive compounds of sweet potato cultivars - Paraná, BRS Amélia, and BRS Cuia. The pH, soluble solids (SS), titratable acidity (TA), SS/TA ratio, soluble sugars, and the bioactive compounds - flavonoids, anthocyanins, and carotenoids - were evaluated. The P doses influenced sweet potato cultivars. The dose of 120 kg ha-1 promoted increments in the parameters pH, SS, TA, and SS/TA ratio for the cultivar BRS Cuia. The same dose promoted an increase in total soluble sugars for the cultivar BRS Amélia. P dose of 240 kg ha-1 promoted higher levels of flavonoids and anthocyanins in the cultivar Paraná, and there was an increase in carotenoid content at the dose of 60 kg ha-1.

Impact of Sodium Nitroprusside on the Photosynthetic Performance of Maize and Sorghum.

Nitric oxide (NO) is an important molecule in regulating plant growth, development and photosynthetic performance. This study investigates the impact of varying concentrations (0-300 µM) of sodium nitroprusside (SNP, a donor of NO) on the functions of the photosynthetic apparatus in sorghum (Sorghum bicolor L. Albanus) and maize (Zea mays L. Kerala) under physiological conditions. Analysis of the chlorophyll fluorescence signals (using PAM and the JIP-test) revealed an increased amount of open PSII reaction centers (qP increased), but it did not affect the number of active reaction centers per PSII antenna chlorophyll (RC/ABS). In addition, the smaller SNP concentrations (up to 150 μM) alleviated the interaction of QA with plastoquine in maize, while at 300 μM it predominates the electron recombination on QAQB-, with the oxidized S2 (or S3) states of oxygen evolving in complex ways in both studied plant species. At the same time, SNP application stimulated the electron flux-reducing end electron acceptors at the PSI acceptor side per reaction center (REo/RC increased up to 26%) and the probability of their reduction (φRo increased up to 20%). An increase in MDA (by about 30%) and H2O2 contents was registered only at the highest SNP concentration (300 µM). At this concentration, SNP differentially affected the amount of P700+ in studied plant species, i.e., it increased (by 10%) in maize but decreased (by 16%) in sorghum. The effects of SNP on the functions of the photosynthetic apparatus were accompanied by an increase in carotenoid content in both studied plants. Additionally, data revealed that SNP-induced changes in the photosynthetic apparatus differed between maize and sorghum, suggesting species specificity for SNP's impact on plants.

Overcoming Low Germination and Low Quality of Flax Seeds (Linum usitatissimum L.) in Unfavorable Storage Using Static Magnetic Fields

Flax seeds stored in unfavorable conditions were exposed to static magnetic fields (SMFs) of 50–350 mT for 20–120 min to overcome low germination and quality. Seed germination increased slightly with increasing strength of SMF and duration of treatment. Seed germination from 89% to 100% was achieved in SMF treatments of 150 mT (120 min), 200 mT (80–120 mT), 250 mT (60–120 min), 300 mT (40–120 min), and 350 mT (40–120 min). In these treatments, germination was 2.78- to 3.12-fold higher than in the control after 10 days. Treatments with 350 mT for 100 and 120 min showed the best results in germination (100%), as well as a 26.81-fold increase in vigor I, 28.69-fold increase in vigor II, 1-fold increase in chlorophyll a, 0.84-fold in chlorophyll b, 0.46-fold increase in carotenoid content, and 2.63-fold increase in catalase activity compared to the control after 10 days. Also, SMF treatment of 350 mT (20–120 min) reduced cell leakage and electrical conductivity by 1-fold compared to the control. SMF is a healthy, biologically safe, and environmentally friendly treatment and can be a tool for overcoming problems of low germination and quality of seeds stored under unfavorable conditions.

Biodegradable Mulching Film vs. Traditional Polyethylene: Effects on Yield and Quality of San Marzano Tomato Fruits.

Mulching is a common practice for improving crop yield and obtaining an out-of-season production, but when made using plastic materials it can bring environmental problems due to the management and the disposal of films at the end of the cropping seasons. To increase the sustainability of this practice, recently, mulching films made with biodegradable organic materials have become more widely used. Our aim was to evaluate the effect of a biodegradable mulching film on yield and qualitative traits of the San Marzano tomato fruits over two years (2014 and 2015). Two different types of mulching were tested: (i) black biodegradable film (MB12) and (ii) black low-density polyethylene (LDPE) were compared to bare soil (BS). Both mulching films elicited a 25% increase in yield, mainly due to the significantly higher number of fruits per square meter, compared to BS. Both mulching films also elicited a 9.9% increase in total soluble solids and a 57% increase in carotenoid content, while firmness showed the highest value in BS fruits. MB12 determined the highest value of the Hunter color ratio a/b of tomato fruits, followed by LDPE, while the lowest value was recorded in BS fruits. Both mulching films elicited an increase of 9.6%, 26.0%, and 11.7% for flavonoids, polyphenols, and AsA, respectively. In 2014, the MB12 degradation started at 71 days after transplant (DAT); in 2015, at 104 DAT. Therefore, replacing polyethylene with biodegradable film would seem to be an agronomically efficient and environmentally sustainable practice.

Towards carotenoid biofortification in wheat: identification of XAT-7A1, a multicopy tandem gene responsible for carotenoid esterification in durum wheat

Yellow pigment content, mainly due to the accumulation of carotenoids, is a quality trait in durum wheat grain as it confers the bright yellow color to pasta preferred by consumers. Also, carotenoids are essential nutrients exerting important biological functions in human health. Consequently, biofortification strategies have been developed in many crops to increase carotenoid content. In this context, carotenoid esterification is emerging as a new breeding target for wheat biofortification, as carotenoid esters have been found to promote both carotenoid accumulation and stability. Until recently, no carotenoid esters have been identified in significant proportions in durum wheat grains, and interspecific breeding programs have been started to transfer esterification ability from common wheat and Hordeum chilense.In this work, XAT-7A1 is identified as the gene responsible for carotenoid esterification in durum wheat. Sequencing, copy number variation and mapping results show that XAT-7A1 is organized as tandem or proximal GDSL esterase/lipase copies in chromosome 7A. Three XAT-7A1 haplotypes are described: Type 1 copies, associated with high levels of carotenoid esters (diesters and monoesters) production and high expression in grain development; Type 2 copies, present in landraces with low levels of carotenoid esters (monoesters) or no esters; and Type 3 copies, without the signal peptide, resulting in zero-ester phenotypes.The identification of XAT-7A1 is a necessary step to make the carotenoid esterification ability available for durum and bread wheat breeding, which should be focused on the Type 1 XAT-7A1 haplotype, which may be assessed as a single gene since XAT-7A1 copies are inherited together.

Integrated Transcriptome and Biochemical Analysis Provides New Insights into the Leaf Color Change in Acer fabri

Acer fabri is a widely distributed ornamental tree with colorful leaves and high ornamental value. Its young leaves change from red to red and green until turning fully green. To understand the mechanism of leaf color change, transcriptome sequencing and pigment content determination were performed in three stages during the leaf color change of A. fabri. In total, 53,550 genes, including 838 transcription factors (TFs), were identified by transcriptome sequencing. In addition, the results of orthogonal partial least squares-discriminant analysis (OPLS-DA) of three pigments in the three stages of leaf color development suggested that carotenoids played a major role in the process of leaf color change from red to red-green, whereas anthocyanins played an important role in the process of leaf color change from red to green. Based on weighted gene co-expression network analysis (WGCNA), Af0034384 (HSFB2A), Af0051627 (NMT1), and Af0052541 (THY-1) were selected as hub genes from characteristic modules with significant correlation between carotenoids and anthocyanins. The results of gene network regulation maps and real-time fluorescence quantitative PCR (qRT-PCR) showed that Af0010511 (NAC100) upregulated the expression of Af0034384 (HSFB2A), leading to an increase in carotenoid content and the gradual greening of leaves during the transition from red to green. However, during the transition from red to green leaves, Af0033232 (NAC83) and Af0049421 (WRKY24) downregulated the expression of Af0051627 (NMT1) and Af0052541 (THY-1), respectively, leading to a decrease in anthocyanin content and the complete greening of leaves. These results could provide new ideas for studying the molecular mechanism of leaf color change in A. fabri and other species.

Heterologous Overexpression of Apple MdKING1 Promotes Fruit Ripening in Tomato.

Fruit ripening is governed by a complex regulatory network, and ethylene plays an important role in this process. MdKING1 is a γ subunit of SNF1-related protein kinases (SnRKs), but the function was unclear. Here, we characterized the role of MdKING1 during fruit ripening, which can promote fruit ripening through the ethylene pathway. Our findings reveal that MdKING1 has higher expression in early-ripening cultivars than late-ripening during the early stage of apple fruit development, and its transcription level significantly increased during apple fruit ripening. Overexpression of MdKING1 (MdKING1 OE) in tomatoes could promote early ripening of fruits, with the increase in ethylene content and the loss of fruit firmness. Ethylene inhibitor treatment could delay the fruit ripening of both MdKING1 OE and WT fruits. However, MdKING1 OE fruits turned fruit ripe faster, with an increase in carotenoid content compared with WT. In addition, the expression of genes involved in ethylene biosynthesis (SlACO1, SlACS2, and SlACS4), carotenoid biosynthesis (SlPSY1 and SlGgpps2a), and fruit firmness regulation (SlPG2a, SlPL, and SlCEL2) was also increased in the fruits of MdKING1 OE plants. In conclusion, our results suggest that MdKING1 plays a key role in promoting tomato fruit ripening, thus providing a theoretical basis for apple fruit quality improvement by genetic engineering in the future.

Sunflower physiological adjustments to elevated CO2 and temperature do not improve reproductive performance and productivity

High levels of carbon dioxide (eCO2) and temperature (eT) affect the physiological performance of sunflowers, but the full extent of their influence on productivity and floral traits remains to be disclosed. Here, we show that eT increased the maximum rate of carboxylation, maximum electron transport capacity, and net rate of triose-phosphate production, indicating enhanced carbon fixation. Although eT increased reactive oxygen species (ROS) concentration in the leaves, no signs of lipid peroxidation in cellular membranes were detected, and plants activated antioxidant systems to counteract the increase in ROS. Moreover, under eT, sunflower pollen exhibited higher amounts of Fe and Zn but also experienced reduced development and productivity due to increased production of empty seeds. In response to eCO2, sunflowers reduced stomatal conductance, limiting water loss, contributing to increased water use efficiency and enhanced photosynthesis. Additionally, under eCO2, sunflowers displayed pollen with higher levels of P, increased biomass gain, and productivity. Lastly, the isolated effects of eCO2 and eT had contrasting impacts on inflorescence size, but the combination of these factors did not result in changes compared to current conditions. However, both factors contributed to increased carotenoid content in ray florets. In contrast, the eCO2eT combination enhanced photosynthesis, flavonoid production in ray florets, and reduced the amount of K and Cu in pollen. In conclusion, eCO2eT improved the physiological performance of sunflowers, but this was not accompanied by increased growth and productivity. The reduction in seed production in sunflowers can have negative impacts on ecology, genetic diversity, and agricultural economy. While eCO2eT did not affect sunflower inflorescence size, they did affect petal pigmentation and pollen quality, which can have significant implications for pollinator health. Understanding the full extent of eCO2eT effects poses a challenge for developing effective mitigation strategies and optimizing agricultural sustainability in the face of climate change.

Cucumber abscisic acid 8'-hydroxylase Csyf2 regulates yellow flesh by modulating carotenoid biosynthesis.

Cucumber (Cucumis sativus L.) flesh is typically colorless or pale green. Flesh with yellow or orange pigment, determined mainly by carotenoid content and composition, is mostly found in semi-wild Xishuangbanna cucumber, which has a very narrow genetic background. Here, we identified a spontaneous cucumber mutant with yellow flesh (yf-343), which accumulated more β-cryptoxanthin and less lutein than regular cultivated European glasshouse-type cucumbers. Genetic analysis revealed that the yellow flesh phenotype was controlled by a single recessive gene. Through fine mapping and gene sequencing, we identified the candidate gene C. sativus yellow flesh 2 (Csyf2), encoding an abscisic acid (ABA) 8'-hydroxylase. Overexpression and RNAi-silencing of Csyf2 in cucumber hairy roots produced lower and higher ABA contents than in non-transgenic controls, respectively. Further, RNA-seq analysis suggested that genes related to ABA signal transduction were differentially expressed in fruit flesh between yf-343 and its wild type, BY, with white flesh. The carotenoid biosynthesis pathway was specifically enriched in fruit flesh at 30 days after pollination when yf-343 fruit flesh turns yellow. Our findings highlight a promising target for gene editing to increase carotenoid content, expanding our genetic resources for pigmented cucumber flesh breeding for improving the nutritional quality of cucumber.

Comparative study of leaf nutrient reabsorption by two different ecotypes of wild soybean under low-nitrogen stress.

Wild soybean (Glycine soja), the ancestor of cultivated soybean, has evolved into many ecotypes with different adaptations to adversity under the action of divergent evolution. Barren-tolerant wild soybean has developed adaptation to most nutrient-stress environments, especially with respect to low nitrogen (LN) conditions. This study describes the differences in physiological and metabolomic changes between common wild soybean (GS1) and barren-tolerant wild soybean(GS2) under LN stress. Compared with plants grown under the unstressed control (CK) conditions, the young leaves of barren-tolerant wild soybean under LN conditions maintained relatively stable chlorophyll, concentration and rates of photosynthesis and transpiration, as well as increased carotenoid content, whereas the net photosynthetic rate (PN) of GS1 decreased significantly 0.64-fold (p < 0.05) in the young leaves of GS1. The ratio of internal to atmospheric CO2 concentrations increased significantly 0.07-fold (p < 0.05), 0.09-fold (p < 0.05) in the young leaves of GS1 and GS2, respectively, and increased significantly 0.05-fold (p < 0.05) and 0.07-fold (p < 0.05) in the old leaves of GS1 and GS2, respectively, relative to the CK. The concentration of chlorophylls a and b decreased significantly 0.45-fold (p < 0.05), 0.13-fold (p > 0.05) in the young leaves of GS1 and GS2, respectively, and decreased significantly 0.74-fold (p < 0.01) and 0.60-fold (p < 0.01) in the old leaves of GS1 and GS2, respectively. Under LN stress, nitrate concentration in the young leaves of GS1 and GS2 decreased significantly 0.69- and 0.50-fold (p < 0.01), respectively, relative to CK, and decreased significantly 2.10-fold and 1.77-fold (p < 0.01) in the old leaves of GS1 and GS2, respectively. Barren-tolerant wild soybean increased the concentration of beneficial ion pairs. Under LN stress, Zn2+ significantly increased by 1.06- and 1.35-fold (p < 0.01) in the young and old leaves of GS2 (p < 0.01), but there was no significant change in GS1. The metabolism of amino acids and organic acids was high in GS2 young and old leaves, and the metabolites related to the TCA cycle were significantly increased. The 4-aminobutyric acid (GABA) concertation decreased significantly 0.70-fold (p < 0.05) in the young leaves of GS1 but increased 0.21-fold (p < 0.05) significantly in GS2. The relative concentration of proline increased significantly 1.21-fold (p < 0.01) and 2.85-fold (p < 0.01) in the young and old leaves of GS2. Under LN stress, GS2 could maintain photosynthesis rate and enhance the reabsorption of nitrate and magnesium in young leaves, compared to GS1. More importantly, GS2 exhibited increased amino acid and TCA cycle metabolism in young and old leaves. Adequate reabsorption of mineral and organic nutrients is an important strategy for barren-tolerant wild soybeans to survive under LN stress. Our research provides a new perspective on the exploitation and utilization of wild soybean resources.

ULTRASOUND-ASSISTED EXTRACTION SENYAWA ANTIOKSIDAN DARI LIMBAH BIJI PEMBUATAN MINYAK BUAH MERAH (Pandanus conoideus)

The aim of this research was to obtain antioxidant active component from Papuan red fruit oil waste using Ultrasound-assisted extraction. The research was done started from the making of Papuan red fruit oil, extraction and bioactive component analysis (total tocopherol and betacaroten) using spectrophotometry. The result shows that waste from Papuan red fruit oil process contains high amount of yield at 20 minutes extraction time with total carotenoid 20, 23 ppm and tocopherol absorbance 1.04. Ultrasound assisted extraction method significantly increase carotenoid content aw well as tocopherol (p&lt;0.05).

Comparative Study of Conventional, Microwave-Assisted and Supercritical Fluid Extraction of Bioactive Compounds from Microalgae: The Case of Scenedesmus obliquus

The recovery of bioactive products with green processes is a critical topic for the research and industry fields. In this work, the application of solid–liquid (SLE), microwave-assisted extraction (MAE) with aq. ethanol 90% v/v and supercritical fluid extraction (SFE) with CO2 for the recovery of biocomponents from Scenedesmus obliquus is studied. The effects examined were temperature (30–60 °C), time (6–24 h), and solvent-to-biomass ratio (20–90 mLsolv/gbiom) for SLE, temperature (40–60 °C), time (5–25 min), solvent-to-biomass ratio (20–90 mLsolv/gbiom), and microwave power (300–800 W) for MAE, and temperature (40–60 °C), pressure (110–250 bar), solvent flow rate (20–40 gsolv/min), and cosolvent presence (0, 10% w/w ethanol) for SFE in relation to the extract’s yield, phenolic, chlorophyll, carotenoid content, and antioxidant activity. The optimum extraction conditions determined were 30 °C, 24 h, and 90 mLsolv/gbiom for SLE, 60 °C, 5 min, 90 mLsolv/gbiom, and 300 W for MAE, and 60 °C, 250 bar, and 40 gsolv/min for SFE. Additionally, a kinetic SFE study was conducted and the obtained results were satisfactorily correlated using Sovová’s model. The comparison between the methods proved MAE’s efficiency in all terms compared to SLE. Moreover, SFE was accompanied with the lowest yield and chlorophyll content, yet led to an increased carotenoid content and improved antioxidant activity. Finally, the cosolvent addition significantly improved SFE’s yield and led to the most superior extract.