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1.
BMC Genomics ; 25(1): 1026, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39487388

RESUMO

Colored leaves, a notable horticultural trait, have high research and ornamental value. The evergreen sweet olive (Osmanthus fragrans), one of the top ten traditional flowers in China, has been cultivated for more than two thousand years. However, in recent years, an increasing number of O. fragrans cultivars with colored leaves have been cultivated for their ornamental value. To study the molecular mechanism underlying the observed changes in leaf color, we selected O. fragrans 'Yinbi Shuanghui' (Y), which has yellow-white leaves, and O. fragrans 'Sijigui' (S), which has green leaves, as materials. Pigment content measurement showed that the chlorophyll, carotenoid and anthocyanin contents in Y were lower than in S. According to the SWATH-MS sequencing results, a total of 3,959 proteins were quantitatively identified, 1,300 of which were differentially expressed proteins (DEPs), including 782 up-regulated and 518 down-regulated proteins in Y compared to S. Functional enrichment analysis of DEPs revealed that down-regulated expression of photosynthesis related proteins may lead to the inhibition of chlorophyll synthesis in Y, this may be the main cause of leaf color change. Moreover, a protein interaction prediction model also showed that proteins such as PetC, PsbO, PsbP, and PsbQ were key proteins in the interaction network, and the up-regulated proteins participating in the anthocyanin and carotenoid pathways may be related to the formation of yellow-white leaves. Taken together, our findings represent the first SWATH-MS-based proteomic report on colored leaf O. fragrans and reveal that chlorophyll synthesis and secondary metabolism pathways contribute to the changes in leaf color.


Assuntos
Fotossíntese , Folhas de Planta , Proteínas de Plantas , Proteômica , Folhas de Planta/metabolismo , Proteômica/métodos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Oleaceae/metabolismo , Oleaceae/genética , Clorofila/metabolismo , Metabolismo Secundário , Espectrometria de Massas , Carotenoides/metabolismo , Pigmentação , Regulação da Expressão Gênica de Plantas , Proteoma/metabolismo , Redes e Vias Metabólicas , Antocianinas/metabolismo , Olea/metabolismo , Olea/genética
2.
BMC Biotechnol ; 24(1): 74, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375686

RESUMO

This study aimed to optimize the production of carotenoid pigments from Micrococcus luteus (ATCC 9341) through the statistical screening of media components and the characterization of antimicrobial, antioxidant, cytogenetic and cytotoxic activities. A BOX-Behnken design was used to assess the effects of whey concentration, inoculum size, pH, temperature, and agitation speed on carotenoid yield. The optimum combination increased production to 2.19 g/L, with a productivity of 0.045 g L-1 h-1 and a productivity yield of 0.644 g/g, as confirmed by an observed carotene production of 2.19 g/L. The final response surface model fitting the data had an R2 of 0.9461. High-performance liquid chromatography (HPLC) analysis identified 12 carotenoid pigment compounds produced by M. luteus. The extracts displayed moderate antimicrobial efficacy against Gram-positive bacteria such as Bacillus cereus (ATCC 11778), Staphylococcus aureus (ATCC 6538), and E. faecalis (ATCC 19433), with inhibition zone diameters (IZD) of 29.0, 14.0, and 37.0 mm, respectively, at 1000 µg/mL. However, its effectiveness against Gram-negative bacteria is limited. In comparison, tetracycline exhibited greater antimicrobial potency. The IC50 value of carotenoids was used to indicate the antioxidant activity. IC50 value from the DPPH assay was 152.80 mg/100mL. An IC50 cytotoxicity value greater than 300 µg/mL was found against normal mouse liver cells, with over 68% cell viability even at 300 µg/mL, indicating low toxicity. Histological structure studies revealed normal myocardial muscle tissue, lung tissue, and kidney tissue sections, whereas liver tissue sections revealed ballooning degeneration of hepatocytes and disorganization of hepatic cords. Cytogenetic parameters revealed that the carotene treatment group had a mitotic index (70%) lower than that of the control but higher than that of the positive control, mitomycin, and did not substantially increase numerical (1.2%) or structural aberrations compared with those of the control, suggesting a lack of genotoxic effects under the experimental conditions. In conclusion, optimized culture conditions enhanced carotenoid yields from M. luteus, and the extracts displayed promising bioactivity as moderate antibiotics against certain gram-positive bacteria and as antioxidants. The high IC50 values demonstrate biosafety. Overall, this bioprocess for enhanced carotenoid production coupled with bioactivity profiling and low cytotoxicity support the application of M. luteus carotenoids.


Assuntos
Antioxidantes , Carotenoides , Micrococcus luteus , Soro do Leite , Micrococcus luteus/efeitos dos fármacos , Carotenoides/farmacologia , Carotenoides/química , Animais , Soro do Leite/química , Antioxidantes/farmacologia , Antioxidantes/química , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias Gram-Positivas/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana
3.
Enzyme Microb Technol ; 181: 110520, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39378559

RESUMO

Dunaliella can accumulate more ß-carotene (10 % or even more of the dry weight of cells) than any other species. Lycopene ß-cyclase (LcyB) is the key enzyme in the catalysis of lycopene to ß-carotene. In the present research, we used Escherichia coli BL21 (DE3) as host to construct two different types of engineering bacteria, one expressing the D. bardawil LcyB and the other expressing the orthologue Erwinia uredovora crtY. The catalytic ability of LcyB and CrtY were evaluated by comparing the ß-carotene yields of the two E. coli BL21(DE3) strains, whose salt tolerance was simultaneously compared by cultivated them under different NaCl concentrations (1 %, 2 %, and 4 %). We also interfered with the LcyB gene to investigate the effect of LcyB in D. bardawil. Results displayed that the ß-carotene yield of the LcyB-transformant significantly increased by about 48 % compared with the crtY-transformant. Additionally, LcyB was verified to be able to enhance the salt tolerance of E. coli BL21 (DE3). It is concluded that D. bardawil LcyB not only has better catalytic ability but also is able to confer salt tolerance to cells. Interfering D. bardawil LcyB induced the low expression of LcyB and the changes of growth and carotenoids metabolism in D. bardawil.

4.
Mar Drugs ; 22(10)2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39452846

RESUMO

Extraction of lipids and high-value products from highly wet microalgae requires significant energy for the drying pretreatment. In this study, we examined the direct extraction of lipids, ß-carotene, and polyphenolic compounds from wet Dunaliella salina using liquefied dimethyl ether (DME), which is effective in lipid extraction for biofuel production. The amount of DME-extracted ß-carotene was 7.0 mg/g, which was higher than that obtained from the chloroform-methanol extraction. Moreover, the total phenolic content extracted with DME and its antioxidant capacity were slightly higher than those extracted with chloroform-methanol. DME removed almost all the water and extracted 29.2 wt% of total lipids and 9.7 wt% of fatty acids. More lipids were extracted from wet samples by liquefied DME than by chloroform-methanol extraction. The C/N ratio of lipids extracted with DME was 112.0, higher than that of chloroform-methanol. The high C/N ratio suggests that nitrogen-containing phosphatidylcholines may be less easily extracted by liquefied DME and may be highly selective. However, the ratio of saturated fatty acids was 34.8%, lower than that of chloroform-methanol. Na+ and Mg2+ in the culture medium were not extracted using DME. Thus, using the extract with DME has both advantages and disadvantages compared to using the extract with chloroform-methanol; however, it has satisfactory extraction properties. DME is expected to be an environment-friendly alternative solvent because it does not require drying, which is necessary for conventional extraction solvents.


Assuntos
Lipídeos , Microalgas , Polifenóis , beta Caroteno , beta Caroteno/química , Microalgas/química , Polifenóis/isolamento & purificação , Polifenóis/química , Lipídeos/química , Antioxidantes/isolamento & purificação , Antioxidantes/química , Antioxidantes/farmacologia , Éteres/química , Ácidos Graxos/isolamento & purificação , Ácidos Graxos/química , Solventes/química , Clorofórmio/química , Éteres Metílicos
5.
Curr Med Chem ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39411947

RESUMO

Glioblastoma (GBM) is a malignant primary brain tumor with a poor prognosis and high recurrence rates. At present, the current treatments available for GBM patients can only prolong their overall survival and cannot provide a complete cure. Discovering an effective therapy against the disease is a challenge due to its recurrence and resistance to common available treatments for GBM. Several natural products have been documented to possess the potential to function as anticancer agents through diverse mechanisms. Astaxanthin (AXT) is an orange-red pigment that is a natural lipophilic and xanthophyll carotenoid derived mostly from microalgae. Numerous studies have examined that AXT impacts GBM cells in laboratory settings and animal models. This review aims to provide the latest information about the potential of astaxanthin as a novel therapeutic option for GBM. AXT has been targeted more on reactive oxygen species (ROS), and suppressed tumor growth in vitro and in vivo conditions. The available data suggests that AXT might serve as a key component in the development of innovative cancer therapies, especially for glioblastoma.

6.
J Anim Sci Technol ; 66(5): 891-904, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39398315

RESUMO

The primary cause of sperm quality decline during the freeze-thaw pathway is the peroxidation hazard caused by reactive oxygen species produced by the biological molecules of sperm. Ascorbic acid (Vitamin C) and lycopene are two potent antioxidants that operate to prevent oxidation processes. This study aimed to analyse the effects of ascorbic acid and lycopene on the motility, viability, abnormality and plasma membrane integrity of post-thawed Sapudi rams. Sperm samples were obtained and pooled from six sexually mature Sapudi rams, separated into ten equal proportions and diluted with Tris-egg yolk-glycerol (TEY) extender. Semen was supplemented with 0 (C0; L0), 1 (C1; L1), 2 (C2; L2), 3 (C3; L3) and 4 (C4; L4) mg/100 mL (1%-4%) diluent each of ascorbic acid and lycopene, respectively. Total sperm motility, viability, abnormalities and semen membrane plasma (%) were analysed after thawing. C3 and L3 extenders resulted in higher total motility (p < 0.05) compared to the other extenders, with all treatments higher than that of the control. The extender C3 (p < 0.05) exhibited the highest semen quality. Finally, the current findings show that C3 and L3 can increase the quality of post-thawed Sapudi ram spermatozoa.

7.
Plant Sci ; 350: 112290, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39396618

RESUMO

Flower color is important in determining the ornamental value of Brassica species. However, our knowledge about the regulation of flower color in pak choi [Brassica campestris (syn. Brassica rapa) ssp. chinensis] is limited. In this study, we investigated the molecular mechanism underlying white flower traits in pak choi by analyzing a genetic population with white and yellow flowers. Our genetic analysis revealed that the white trait is controlled by a single recessive gene called Bcwf. Through BSA-Seq and fine mapping, we identified a candidate gene, BraC02g039450.1, which is similar to Arabidopsis AtPES2 involved in carotenoid ester synthesis. Sequence analysis showed some mutations in the promoter region of Bcwf in white flowers. Tobacco transient assay confirmed that these mutations reduce the promoter's activity, leading to downregulation of Bcwf expression in white flowers. Furthermore, the silencing of Bcwf in pak choi resulted in lighter petal color and reduced carotenoid content. These findings provide new insights into the molecular regulation of white flower traits in pak choi and highlight the importance of Bcwf in petal coloring and carotenoid accumulation.

8.
Foods ; 13(20)2024 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-39456385

RESUMO

The Mediterranean Diet (MD) is characterized by a high intake of fruits and vegetables (FVs), which is considered as an important contributor to the beneficial effects of the MD pattern. In this cross-sectional study, we compared the food choices, evaluated by dietary habit questionnaires, of a sample of 995 adults, including 601 and 394 participants from Southern Italy and the Dominican Republic, respectively. In addition, we focused on their FV consumption, assessed by the Mediterranean Diet Adherence Screener (MEDAS) questionnaire, and on its association with skin carotenoid levels as measured by the Veggie Meter®. We found that a significantly higher percentage of Italians had five meals/day and breakfast compared to Dominicans (five meals/day: 43 vs. 25, p < 0.05; breakfast: 89 vs. 79, p < 0.05), whereas a lower percentage of participants from Italy consumed snacks between the two meals compared to the Dominican Republic population (47 vs. 70, p < 0.005). Most of the participants from both populations had breakfast at home. However, 59.3% of Italians and 27.5% of Dominicans (p = 0.005) had breakfast between 7:00 and 9:00 a.m., whereas 5.8% and 27.5% (p = 0.001) had breakfast after 9:00 a.m., respectively. Milk/yogurt and eggs were the most consumed foods for breakfast in Italy and the Dominican Republic, respectively. Regarding the main meals, most of the Italians and Dominicans had a first course for lunch and a second course for dinner. Of note, we observed that approximately half of the Italians ate FVs in their main meals and had a higher carotenoid score than the Dominicans. Interestingly, in the multiple linear regression analysis, we found that the carotenoid score was positively associated with sex (ß = 0.078; p = 0.009), age (ß = 0.008; p = 0.001), vegetable consumption (ß = 0.12; p = 0.041) and the perception of a healthy diet (ß = 0.12; p = 0.001) in the Dominic Republic population, while the carotenoid score was directly associated with sex (ß = 54.97; p < 0.0001) and both vegetable (ß = 25.42; p = 0.0008) and fruit (ß = 38.61; p < 0.0001) consumption in the Italian sample. Our findings confirm the need to promote nutrition-based interventions to encourage FV intake, particularly in non-Mediterranean countries.

9.
Plants (Basel) ; 13(20)2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39458853

RESUMO

Pomegranate (Punica granatum L.) is an ancient fruit crop that has been cultivated worldwide and is known for its attractive appearance and functional metabolites. Fruit color is an important index of fruit quality, but the color formation pattern in the peel of evergreen pomegranate and the relevant molecular mechanism is still unknown. In this study, the contents of pigments including anthocyanins, carotenoids, and chlorophyll in the peel of 'Danruo No. 1' pomegranate fruit during three developmental stages were measured, and RNA-seq was conducted to screen key genes regulating fruit color formation. The results show that pomegranate fruit turned from green to red during development, with a dramatic increase in a* value, indicating redness and anthocyanins concentration, and a decrease of chlorophyll content. Moreover, carotenoids exhibited a decrease-increase accumulation pattern. Through RNA-seq, totals of 30, 18, and 17 structural genes related to anthocyanin biosynthesis, carotenoid biosynthesis and chlorophyll metabolism were identified from differentially expressed genes (DEGs), respectively. Transcription factors (TFs) such as MYB, bHLH, WRKY and AP2/ERF were identified as key candidates regulating pigment metabolism by K-means analysis and weighted gene co-expression network analysis (WGCNA). The results provide an insight into the theory of peel color formation in evergreen pomegranate fruit.

10.
Int J Biol Macromol ; 281(Pt 3): 136354, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39378920

RESUMO

Chromoplasts are specialized plastids in plants involved in carotenoid synthesis, accumulation, and stress resistance. In tomatoes (Solanum lycopersicum), the Chromoplast-associated carotenoid binding protein (CHRC) regulates chromoplast development and carotenoid accumulation, although its precise mechanisms are not yet fully understood. To investigate the role of SlCHRC in carotenoid biosynthesis, we generated transgenic tomatoes using overexpression (oe-SlCHRC) and CRISPR/Cas9-mediated gene editing (cr-SlCHRC) techniques. The results demonstrated inhibited fruit ripening and delayed onset of color break in both transgenic lines. The oe-SlCHRC lines exhibited increased carotenoid accumulation, particularly (E/Z)-phytoene, lycopene, and γ-carotene, with abundant plastoglobules and carotenoid crystals observed via TEM. In contrast, cr-SlCHRC mutants showed a greener phenotype, reduced carotenoid content, and fewer plastoglobules at the BK + 10 stage. Transcriptome analysis indicated that SlCHRC influences key genes in carotenoid biosynthesis, such as SlNCED2, as well as genes related to chloroplast development, photosynthesis, and plastoglobule formation. Additionally, SlCHRC enhances heat stress tolerance in tomato fruits by upregulating heat shock proteins (HSPs), antioxidants, and proline accumulation. These findings indicate that SlCHRC plays a crucial role in improving tomato fruit quality under heat stress conditions.

11.
Plant Physiol ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39365917

RESUMO

Stress exerted by excess captured light energy in cyanobacteria is prevented by the photoprotective activity of the orange carotenoid protein (OCP). Under high light, the OCP converts from an orange, inactive form (OCPO) into the red form (OCPR) that binds to and quenches the phycobilisome (PBS). Structurally, the OCP consists of two domains: the N-terminal effector domain and a C-terminal regulatory domain. Structural analysis of the OCP-PBS complex showed that the N-terminal domains of an OCP dimer interact with the PBS core. These N-terminal OCP domains have single domain protein paralogs known as Helical Carotenoid Proteins (HCPs). Using phycobilisome quenching assays, we show that the HCP4 and HCP5 homologs efficiently quench PBS fluorescence in vitro, surpassing the quenching ability of the OCP. This is consistent with computational quantum mechanics/molecular mechanics results. Interestingly, when using a maximum quenching concentration of OCP with phycobilisomes, HCP5 addition further increases phycobilisome quenching. Our results provide mechanistic insight into the quenching capacity and roles of HCP4 and HCP5 in cyanobacteria, suggesting that they are more than simply functionally redundant to the OCP.

12.
Plant Sci ; 350: 112298, 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39442633

RESUMO

Carotenoids are a large class of isoprenoid compounds which are biosynthesized by plants, algae, along with certain fungi, bacteria and insects. In plants, carotenoids provide crucial functions in photosynthesis and photoprotection. Furthermore, carotenoids also serve as precursors to apocarotenoids, which are derived through enzymatic and non-enzymatic cleavage reactions. Apocarotenoids encompass a diverse set of compounds, including hormones, growth regulators, and signaling molecules which play vital roles in pathways associated with plant development, stress responses, and plant-organismic interactions. Regulation of carotenoid biosynthesis indirectly influences the formation of apocarotenoids and bioactive effects on target pathways. Recent discovery of a plethora of new bioactive apocarotenoids across kingdoms has increased interest in expanding knowledge of the breadth of apocarotenoid function and regulation. In this review, we provide insights into the regulation of carotenogenesis, specifically linked to the biosynthesis of apocarotenoid precursors. We highlight plant studies, including useful heterologous platforms and synthetic biology tools, which hold great value in expanding discoveries, knowledge and application of bioactive apocarotenoids for crop improvement and human health. Moreover, we discuss how this field has recently flourished with the discovery of diverse functions of apocarotenoids, thereby prompting us to propose new directions for future research.

13.
Int J Syst Evol Microbiol ; 74(10)2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39418191

RESUMO

Two yellow-pigmented novel strains, designated HF-S3T and HF-S4T, were isolated from farm soil in Paju, Republic of Korea. Cells of the two strains are characteristically Gram-stain-negative, facultatively anaerobic, catalase- and oxidase-positive, non-motile and rod-shaped. Strain HF-S3T grew at 10-37 °C, while HF-S4T grew at 15-35 °C. Both strains grew at pH 5.0-12.0 and in NaCl concentrations (w/v) of 0-2.0%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that HF-S3T and HF-S4T belong to the genus Sphingomonas, with HF-S3T exhibiting 97.7, 97.6 and 97.4% similarity to Sphingomonas cannabina DM2-R-LB4T, Sphingomonas leidyi DSM 4733T and Sphingomonas canadensis FWC47T, respectively. Strain HF-S4T displayed 97.9, 97.7 and 97.6% similarity to Sphingomonas psychrotolerans Cra20T, Sphingomonas gei ZFGT-11T and Sphingomonas naasensis KIS18-15T, respectively. The DNA G+C contents of HF-S3T and HF-S4T were 67.0 and 66.5 mol%, respectively. The digital DNA-DNA hybridization and average nucleotide identity values among the novel and related type strains were 20.2-28.2% and 75.9-84.3%, respectively. They all contained C14:0 2-OH and C16:0, summed feature 8 (C18:1 ω6c and/or C18:1 ω7c) as the major fatty acids and ubiquinone-10 as the predominant respiratory quinone. Strains HF-S3T and HF-S4T were found to produce carotenoid-type pigments. Based on polyphasic taxonomic analysis, the new isolates ostensibly represent two novel species of the genus Sphingomonas, with the proposed names Sphingomonas rustica sp. nov. and Sphingomonas agrestis sp. nov. for strains HF-S3T and HF-S4T, respectively. The S. rustica and S. agrestis type strains are HF-S3T (=KACC 23554T =TBRC 18352T) and HF-S4T (=KACC 23386T =TBRC 17899T), respectively.


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , Carotenoides , DNA Bacteriano , Fazendas , Ácidos Graxos , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Microbiologia do Solo , Sphingomonas , Ubiquinona , Sphingomonas/classificação , Sphingomonas/genética , Sphingomonas/isolamento & purificação , RNA Ribossômico 16S/genética , República da Coreia , DNA Bacteriano/genética
14.
Artigo em Inglês | MEDLINE | ID: mdl-39436867

RESUMO

OBJECTIVES: Neurodegenerative diseases are defined by specific protein accumulation and anatomic vulnerability leading to neuronal loss. Some studies have shown that lutein may have an effect on neurodegenerative diseases. As most of the neurodegenerative diseases don't have certain cure and therapies focus on symptom control, Lutein may be a complementary treatment. Due to controversies in studies investigating lutein effect on neurodegenerative diseases, we decided to perform a systematic review on these studies. METHODS: A systematic search was carried out in the available databases. We used all MeSH terms and relevant keywords. Studies that reported relationship between lutein and any neurodegenerative disease were included. RESULTS: We found 278 studies. After removing duplicates, screening by titles and abstracts and excluding irrelevant papers, 17 articles were included in this study. Fourteen studies investigated Alzheimer's disease, 2 studies Parkinson's disease and 1 study Amyotrophic lateral sclerosis. 1/17 study found that high serum levels of lutein at baseline were associated with a lower risk of AD mortality and lutein effect on lipid profile have been investigated in 2/17 studies. Also, 1/17 study has been shown that high intake of lutein may reduce the risk of ALS progression. CONCLUSIONS: 4/17 studies confirm that lutein can improve cognitive function. 8/17 studies demonstrate a reduction in the progression of AD, and 2/17 studies indicate an improvement in lipid profiles. However, some studies did not find any significant associations. Additionally, there is a limited number of studies investigating the effects of lutein on other neurodegenerative diseases.

15.
Front Nutr ; 11: 1441062, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39403398

RESUMO

Ischemic stroke poses a significant global health challenge with limited treatment options. Tissue plasminogen activator, the only effective medication, has strict restrictions, limiting its benefits only to a small number of patients. Astaxanthin, a natural carotenoid found in algae, shrimp, and crabs, has demonstrated promising neuroprotective properties in models of ischemic stroke. This article reviews the novel finding of neuroprotective impact of astaxanthin in ischemic stroke, highlighting its benefits in various protective mechanisms such as antioxidation, anti-inflammation, enhancement of DNA repair, anti-cell death, protection of blood-brain barrier, and promotion of neuronal survival. This analysis underscores the therapeutic and preventive potential of astaxanthin in ischemic stroke, positioning it as a prospective pharmaceutical agent against ischemic stroke.

16.
Biochemistry (Mosc) ; 89(9): 1573-1581, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39418516

RESUMO

In photosynthetic reaction centers, quenching of the primary donor triplet state by energy transfer to the carotenoid molecule provides efficient suppression of generation of singlet-excited oxygen, potent chemical oxidant. This process in the Cereibacter sphaeroides reaction centers is thermoactivated, and discontinues at temperatures below 40 K. In these reaction centers, substitution of amino acid residue isoleucine at the 177 position of the L-subunit with histidine results in the sharp decrease of activation energy, so that the carotenoid triplets are populated even at 10 K. Activation energy of the T-T energy transfer was estimated as 7.5 cm-1, which is more than 10-fold lower than activation energy in the wild type reaction centers. At certain temperatures, the energy transfer in the mutant is decelerated, which is related to the increase of effective distance of the triplet-triplet transfer. To the best of our knowledge, the described mutation presents the first reaction center modification leading to the significant decrease in activation energy of the T-T energy transfer to carotenoid molecule. The I(L177)H mutant reaction centers present a considerable interest for further studies of the triplet state quenching mechanisms, and of other photophysical and photochemical processes in the reaction centers of bacterial photosynthesis.


Assuntos
Transferência de Energia , Mutação , Complexo de Proteínas do Centro de Reação Fotossintética , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Complexo de Proteínas do Centro de Reação Fotossintética/química , Temperatura , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Rhodobacter sphaeroides/metabolismo , Rhodobacter sphaeroides/genética , Carotenoides/metabolismo , Carotenoides/química
17.
Artigo em Inglês | MEDLINE | ID: mdl-39269488

RESUMO

Polycystic ovary syndrome (PCOS) is a prevalent gynecological-endocrinological disorder characterized by hyperandrogenism, menstrual irregularities, and metabolic disturbances. Recent research has highlighted the role of oxidative stress and chronic inflammation in exacerbating PCOS symptoms and impeding reproductive outcomes. Astaxanthin, a potent antioxidant found in marine organisms, has been suggested as a potential therapeutic intervention due to its ability to reduce oxidative stress and inflammation. This meta-analysis systematically reviews randomized controlled trials assessing the impact of astaxanthin supplementation on oxidative stress and reproductive outcomes in women with PCOS. Data from four trials were analyzed, focusing on markers of oxidative stress and reproductive health metrics. The meta-analysis utilized fixed and random-effects models to synthesize results, with heterogeneity assessed using Chi-square and I2 statistics. The findings indicate that while astaxanthin significantly improves markers of total antioxidant capacity (TAC) in follicular fluid, it does not show a consistent effect on other oxidative stress biomarkers such as malondialdehyde (MDA), catalase (CAT), or superoxide dismutase (SOD). Reproductive outcomes, including oocyte quality and the number of high-quality embryos, showed moderate improvements, although effects on fertilization rates and pregnancy outcomes were insignificant. The analysis highlights variability in study designs and dosing, suggesting a need for further research with standardized protocols and larger sample sizes. Future studies should focus on determining optimal dosing, exploring mechanistic pathways, and investigating the combined effects of astaxanthin with other interventions. Longitudinal studies are needed to assess long-term benefits and safety, and personalized approaches could enhance treatment efficacy for individuals with PCOS.

18.
J Sci Food Agric ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39229826

RESUMO

BACKGROUND: Carotenoids have various physiological functions, such as immune regulation and cancer prevention. Germination could further improve the content of carotenoids in maize seeds. In this study, yellow maize seeds (Suyu 29) were soaked and germinated with different concentrations of 24-epibrassinolide. The changes of germination percentage, sprout length, bioactive components, antioxidant capacity and carotenoid content of the maize seeds were analyzed. Additionally, the relative expression of key genes in the carotenoid synthesis pathway was investigated. RESULTS: The results showed that the sprout length, germination percentage, soluble protein, free amino acids, proline, endogenous abscisic acid, vitamin C, total phenolics and carotenoids displayed a significant increasing trend compared with the control group (P < 0.05). The activity of superoxide dismutase and peroxidase increased by 55.1% and 58.5% versus the control group, and the antioxidant capacity of 2,2-diphenyl-1-picrylhydrazyl, 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and ferric reducing antioxidant power was 19.8%, 13.4% and 44.1% higher than that of the control group (P < 0.05). Compared with the control group, the expression of genes was significantly up-regulated (P < 0.05). Under the treatment of 0.1 mg L-1 of 24-epibrassinolide, carotenoid content reached the highest value. The carotenoids showed a positive correspondence with antioxidant enzyme activity, antioxidant capacity and total phenolics content (P < 0.05). CONCLUSION: This study showed that 0.1 mg L-1 of exogenous 24-epibrassinolide promoted the accumulation of carotenoids and improved the antioxidant capacity and the quality of germinated maize seeds. It could provide a method for the development of germinated maize products enriched in carotenoids. © 2024 Society of Chemical Industry.

19.
Mar Biotechnol (NY) ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39259314

RESUMO

The present study aimed to isolate a bioactive compound from Sri Lankan edible marine brown algae, Chnoospora minima, to manage diabetes. The de-polysaccharide crude methanolic extract was partitioned using hexane, chloroform, and ethyl acetate with increased polarity. The samples were subjected to determine the quantitative phytochemical analysis, antioxidants, and antidiabetic potentials. Further, the potent antidiabetic fraction was selected to isolate an active compound using bioactivity-guided fractionation. From the selected extract, the chloroform fraction exhibited comparatively high TPC (59.01 ± 1.86 mg GAE/g), TFC (5.14 ± 0.43 mg QE/g) and alkaloid content (2.79 ± 0.31 PE/g of extract). Crude methanol extract exhibited a potent DPPH activity (IC50: 0.48 ± 0.01 mg/mL) whereas the ethyl acetate fraction elicited a maximum ABTS activity (IC50: 0.064 ± 0.001 mg/mL) and a ferrous iron-chelating capacity (IC50: 0.019 mg/mL). Similarly, the chloroform fraction exhibited the highest FRAP (20.34 ± 1.72 mg TE/g) and ORAC (19.72 ± 2.92 mg TE/g) capacities. The potent inhibitory activity of α-amylase (IC50:3.17 ± 0.02 µg/mL) and α-glucosidase (IC50: 1.99 ± 0.01 µg/mL) enzymes and glucose diffusion was observed in the chloroform fraction. Similarly, the chloroform extract exhibited a potent BSA-glucose (IC50: 202.43 ± 5.71 µg/mL), BSA-MGO (IC50: 124.30 ± 2.85 µg/mL) antiglycation model and reversing activities (EC50BSAglucose: 98.99 ± 0.35 µg/mL; EC50BSA-MGO: 118.89 ± 1.58 µg/mL). Depending on the hypoglycemic activity, fucoxanthin was isolated as the active compound which showed a notable change in the functional group. Molecular docking studies were conducted on the compound, and binding energy was observed to be - 6.56 kcal/mol and - 4.83 kcal/mol for α-amylase and α-glucosidase enzymes, respectively, which confirmed the hypoglycemic effect of the isolated compounds. However, more studies are required to understand the mechanistic insights of these observations.

20.
Foods ; 13(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39272423

RESUMO

Jujube is a plant of the genus Ziziphus in the family Rhamnaceae; its fruit has high nutritional value, and it is rich in polyphenols, flavonoids, and other secondary metabolites. The color of its peel is an important indicator for evaluating the appearance of the fruit. However, the mechanism of the difference in color presentation between the seedling offspring of the 'Red Fruit' (TLHH) and the 'Green Fruit' (TLHL) of the fresh jujube cultivar 'Tailihong' is not clear. Therefore, this study used targeted metabolomics techniques to accurately and quantitatively analyze the metabolic pathways of carotenoid and anthocyanin metabolites during the ripening process of two color-presenting types of jujube fruits. Through the analysis of the dynamic changes in the pigment content of the jujube peel, it was found that 30 DAP (days after pollination), 80 DAP, and 110 DAP were the key periods for the development of the color of the peel of 'TLHL' and 'TLHH' jujube and that the substances responsible for the main differences were chlorophyll, carotenoids, and anthocyanins. Furthermore, we used an LC-MS/MS metabolic analysis to compare the differences in the carotenoids and anthocyanin metabolites between the two color-presenting types of jujube peels at the key periods of 30 DAP, 80 DAP, and 110 DAP. We detected 32 carotene metabolites and 75 anthocyanin metabolites, respectively, among which lutein had the highest content of carotenoids; it reached the maximum value (93.05 µg/g) and was higher than that of 'TLHH' (74.14 µg/g) at 30 DAP of 'TLHL'. Both showed a decreasing trend with fruit ripening. The anthocyanin with the highest content was cyanidin-3-O-(tartaryl)rhamnoside-5-O-glucoside, which reached the maximum value (258.32 µg/g) at 30 DAP of 'TLHH' and was 51.6 times that of 'TLHL'; similarly, both showed a decreasing trend with fruit ripening. These results elucidate the main metabolites of carotenoids and anthocyanins in the two types of jujube peel and their accumulation characteristics, suggesting that the key metabolites of the difference in color between 'TLHL' and 'TLHH' jujube fruits were lutein and cyanidin-3-O-(tartaryl)rhamnoside-5-O-glucoside, increasing the understanding of the color mechanism of jujube peel and providing a reference for targeted genetic breeding of jujube peel color.

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