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1.
Molecules ; 26(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34500586

RESUMO

Radiation-induced fibrosis (RIF) is a serious, yet incurable, complication of external beam radiation therapy for the treatment of cancer. Macrophages are key cellular actors in RIF because of their ability to produce reactive oxidants, such as reactive oxygen species (ROS) and inflammatory cytokines that, in turn, are the drivers of pro-fibrotic pathways. In a previous work, we showed that phagocytosis could be exploited to deliver the potent natural antioxidant astaxanthin specifically to macrophages. For this purpose, astaxanthin encapsulated into µm-sized protein particles could specifically target macrophages that can uptake the particles by phagocytosis. In these cells, astaxanthin microparticles significantly reduced intracellular ROS levels and the secretion of bioactive TGFß and increased cell survival after radiation treatments. Here we show that pentoxifylline, a drug currently used for the treatment of muscle pain resulting from peripheral artery disease, amplifies the effects of astaxanthin microparticles on J774A.1 macrophages. Combination treatments with pentoxifylline and encapsulated astaxanthin might reduce the risk of RIF in cancer patients.


Assuntos
Macrófagos/efeitos dos fármacos , Microplásticos/química , Pentoxifilina/química , Pentoxifilina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/química , Antioxidantes/farmacologia , Células Cultivadas , Fibrose/tratamento farmacológico , Fibrose/metabolismo , Humanos , Macrófagos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Tolerância a Radiação/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Xantofilas/química , Xantofilas/farmacologia
2.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360729

RESUMO

Mitochondria are considered to be important organelles in the cell and play a key role in the physiological function of the heart, as well as in the pathogenesis and development of various heart diseases. Under certain pathological conditions, such as cardiovascular diseases, stroke, traumatic brain injury, neurodegenerative diseases, muscular dystrophy, etc., mitochondrial permeability transition pore (mPTP) is formed and opened, which can lead to dysfunction of mitochondria and subsequently to cell death. This review summarizes the results of studies carried out by our group of the effect of astaxanthin (AST) on the functional state of rat heart mitochondria upon direct addition of AST to isolated mitochondria and upon chronic administration of AST under conditions of mPTP opening. It was shown that AST exerted a protective effect under all conditions. In addition, AST treatment was found to prevent isoproterenol-induced oxidative damage to mitochondria and increase mitochondrial efficiency. AST, a ketocarotenoid, may be a potential mitochondrial target in therapy for pathological conditions associated with oxidative damage and mitochondrial dysfunction, and may be a potential mitochondrial target in therapy for pathological conditions.


Assuntos
Sistemas de Liberação de Medicamentos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Mitocôndrias Cardíacas/metabolismo , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/patologia , Humanos , Isoproterenol/efeitos adversos , Isoproterenol/uso terapêutico , Mitocôndrias Cardíacas/patologia , Oxirredução/efeitos dos fármacos , Xantofilas/uso terapêutico
3.
Planta ; 254(3): 52, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392410

RESUMO

MAIN CONCLUSION: The compatible solute sucrose reduces the efficiency of the enzymatic de-epoxidation of violaxanthin, probably by a direct effect on the protein parts of violaxanthin de-epoxidase which protrude from the lipid phase of the thylakoid membrane. The present study investigates the influence of the compatible solute sucrose on the violaxanthin cycle of higher plants in intact thylakoids and in in vitro enzyme assays with the isolated enzyme violaxanthin de-epoxidase at temperatures of 30 and 10 °C, respectively. In addition, the influence of sucrose on the lipid organization of thylakoid membranes and the MGDG phase in the in vitro assays is determined. The results show that sucrose leads to a pronounced inhibition of violaxanthin de-epoxidation both in intact thylakoid membranes and the enzyme assays. In general, the inhibition is similar at 30 and 10 °C. With respect to the lipid organization only minor changes can be seen in thylakoid membranes at 30 °C in the presence of sucrose. However, sucrose seems to stabilize the thylakoid membranes at lower temperatures and at 10 °C a comparable membrane organization to that at 30 °C can be observed, whereas control thylakoids show a significantly different membrane organization at the lower temperature. The MGDG phase in the in vitro assays is not substantially affected by the presence of sucrose or by changes of the temperature. We conclude that the presence of sucrose and the increased viscosity of the reaction buffers stabilize the protein part of the enzyme violaxanthin de-epoxidase, thereby decreasing the dynamic interactions between the catalytic site and the substrate violaxanthin. This indicates that sucrose interacts with those parts of the enzyme which are accessible at the membrane surface of the lipid phase of the thylakoid membrane or the MGDG phase of the in vitro enzyme assays.


Assuntos
Galactolipídeos , Tilacoides , Sacarose , Xantofilas
4.
J Agric Food Chem ; 69(34): 9764-9777, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34404210

RESUMO

The marine natural product fucoxanthin has been reported previously to produce anti-Alzheimer's disease (AD) neuroprotective effects in vitro and in vivo. Fucoxanthin was also demonstrated to be safe in preclinical and small population clinical studies, but the low bioavailability of fucoxanthin in the central nervous system (CNS) has limited its clinical applications. To overcome this, poly lactic-co-glycolic acid-block-polyethylene glycol loaded fucoxanthin (PLGA-PEG-Fuc) nanoparticles with diameter at around 200 nm and negative charge were synthesized and suggested to penetrate into the CNS. Loaded fucoxanthin could be liberated from PLGA-PEG nanoparticles by sustained released in the physiological environment. PLGA-PEG-Fuc nanoparticles were shown to significantly inhibit the formation of Aß fibrils and oligomers. Moreover, these nanoparticles were taken up by both neurons and microglia, leading to the reduction of Aß oligomers-induced neurotoxicity in vitro. Most importantly, intravenous injection of PLGA-PEG-Fuc nanoparticles prevented cognitive impairments in Aß oligomers-induced AD mice with greater efficacy than free fucoxanthin, possibly via acting on Nrf2 and NF-κB signaling pathways. These results altogether suggest that PLGA-PEG nanoparticles can enhance the bioavailability of fucoxanthin and potentiate its efficacy for the treatment of AD, thus potentially enabling its future use for AD therapy.


Assuntos
Nanopartículas , Feófitas , Peptídeos beta-Amiloides , Animais , Carotenoides , Portadores de Fármacos , Camundongos , Polietilenoglicóis , Xantofilas
5.
Phytochemistry ; 191: 112912, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34450419

RESUMO

The esterification of carotenoids has been associated with high-level accumulation, greater stability and potentially improved dietary bioavailability. Engineering the formation of ketocarotenoids into tomato fruit has resulted in the esterification of these non-endogenous metabolites. A genotype of tomato was created that contains; (i) the mutant pale yellow petal (pyp)1-1 allele, which is responsible for the absence of carotenoid esters in tomato flowers and (ii) the heterologous enzymes for ketocarotenoid formation. Analysis of the resulting progeny showed altered quantitative and qualitative differences in esterified carotenoids. For example, in ripe fruit tissues, in the presence of the pyp mutant allele, non-endogenous ketocarotenoid esters were absent while their free forms accumulated. These data demonstrate the involvement of the PYP gene product in the esterification of diverse xanthophylls.


Assuntos
Lycopersicon esculentum , Aciltransferases/metabolismo , Esterificação , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Proteínas de Plantas/metabolismo , Plastídeos/metabolismo , Xantofilas/metabolismo
6.
Bioresour Technol ; 340: 125720, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34365300

RESUMO

Haematococcus pluvialis has attracted interest as a bio-platform for producing omega-3 fatty acids (ω-3 FA) and astaxanthin that have a great potential as anti-inflammatory drugs. This study aimed to concurrently enhance the CO2 fixation and the productivities of ω-3 FA and astaxanthin, which have been difficult to achieve because of the dissimilar culture methods for each goal, via calcium-mediated homeoviscous adaptation and biomineralization. As a result of 3 mM of Ca2+ addition, ω-3 FA content was improved by 31% due to Ca2+-induced homeoviscous adaptation. Biomineralization was promoted by the extracellular carbonic anhydrase, which resulted in 46.3% improvement in CO2 fixation. CaCO3 from the biomineralization was beneficially re-used in the H. pluvialis culture and triggered 178- and 522-fold increased biomass productivity and astaxanthin content, respectively, thanks to its anisotropic nature. The Ca2+-based productivity enhancement strategy was applied to large-scale culture which resulted improvement in overall bioprocess performance.


Assuntos
Dióxido de Carbono , Ácidos Graxos Ômega-3 , Biomineralização , Cálcio , Xantofilas
7.
Bioresour Technol ; 340: 125707, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34371336

RESUMO

Haematococcus pluvialis is a green alga that can accumulate high astaxanthin content, a commercially demanding market keto food. Due to its high predicted market value of about 3.4 billion USD in 2027, it is essential to increase its production. Therefore, it is crucial to understand the genetic mechanism and gene expressions profile during astaxanthin synthesis. The effect of poly- and mono-chromatic light of different wavelengths and different intensities have shown to influence the gene expression towards astaxanthin production. This includes transcriptomic gene analysis in H. pluvialis underneath different levels of illumination stress. This review has placed the most recent data on the effects of light on bioastaxanthin production in the context of previous studies, which were more focused on the biochemical and physiological sides. Doing so, it contributes to delineate new ways along the biotechnological process with the aim to increase bioastaxanthin production while decreasing production costs.


Assuntos
Clorofíceas , Clorófitas , Clorófitas/genética , Transcriptoma , Xantofilas
8.
Bioresour Technol ; 340: 125736, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34426245

RESUMO

Astaxanthin is one of the secondary carotenoids involved in mediating abiotic stress of microalgae. As an important antioxidant and nutraceutical compound, astaxanthin is widely applied in dietary supplements and cosmetic ingredients. However, most astaxanthin in the market is chemically synthesized, which are structurally heterogeneous and inefficient for biological uptake. Astaxanthin refinery from Haematococcus pluvialis is now a growing industrial sector. H. pluvialis can accumulate astaxanthin to ∼5% of dry weight. As productivity is a key metric to evaluate the production feasibility, understanding the biological mechanisms of astaxanthin accumulation is beneficial for further production optimization. In this review, the biosynthesis mechanism of astaxanthin and production strategies are summarized. The current research on enhancing astaxanthin accumulation and the potential joint-production of astaxanthin with lipids was also discussed. It is conceivable that with further improvement on the productivity of astaxanthin and by-products, the algal-derived astaxanthin would be more accessible to low-profit applications.


Assuntos
Clorofíceas , Microalgas , Lipídeos , Xantofilas
9.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(4): 433-438, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34374266

RESUMO

Objective: To study the effects and mechanisms of astaxanthin combined with aerobic exercise on renal senescence of rat induced by D-galactose. Methods: Sixty 3-month-old SPF SD rats were divided into control group (C group), acute senescence group (S group), astaxanthin+acute senescence group (AS group), aerobic exercise+acute senescence group (ES group), astaxanthin+aerobic exercise+acute senescence group (AES group), by two-factor two-level 2×2 factorial design with 12 rats in each group. Acute senescence model of rat was establshed by intraperitoneal injection with 100 mg/(kg·d) D-galactose, and the intervention was conducted with 20 mg/(kg·d) astaxanthin and/or aerobic exercise with 60% VO2max for 6 weeks. The histopathological/ultrastructural changes of the kidney were observed by light microscope/electron microscope; the levels of SOD, γ-GCS and MDA were detected by ELISA, and LDF in kidney was determined by fluorescence colorimetry; the protein expression of Nrf2 signaling pathway was detected by immunohistochemistry. Results: Compared with AS and ES group, in AES group, the improvement of renal tissue morphology/ultrastructure was more significant; LDF was decreased significantly (P<0.01); SOD activity was significantly increased (P<0.01); γ-GCS was significantly higher than that of AS group, but not significantly different from that of ES group (P>0.05); there was no significant difference in MDA between groups (P>0.05); the levels of Nrf2 and p-Nrf2 were increased significantly (P<0.05, P<0.01); HO-1 was significantly higher than that of ES group(P<0.05), but not significantly different compared with that of AS group(P>0.05). Conclusion: Astaxanthin combined with aerobic exercise can delay aging process of kidney, its mechanism may be that the combination regulate the protein expression in Nrf2 signaling pathway, Ⅱ detoxifying enzymes and antioxidant enzyme activity, and improve oxidative stress in kidney of rat induced by D-galactose.


Assuntos
Galactose , Fator 2 Relacionado a NF-E2 , Envelhecimento , Animais , Rim/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Xantofilas
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(4): 1312-1317, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34362522

RESUMO

OBJECTIVE: To observe the effect of astaxanthin (ASTA) on the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in suspended leukocyte-depleted red blood cells stored for transfusion. METHODS: The suspended leukocyte-depleted red blood cells were randomly divided into group A, B, C and D. The ASTA was added into preservation solution of suspended leukocyte-depleted red blood cells of group B, C and D with the final concentration 5, 10 and 20 µmol/L, respectively, while DMSO was added into cells of group A in the same volume. After 7, 14, 28 and 42 days of storage, the reactive oxygen species (ROS) content in red blood cells was detected by fluorescence microplate reader, malondialdehyde (MDA) content was detected by thiobarbituric acid (TBA) method, activity of SOD was detected by xanthine oxidase method, the activity of CAT was detected by visible light method, and activity of GSH-Px was detected by colorimetry. RESULTS: After 7, 14, 28 and 42 days of storage, the contents of ROS and MDA in suspended red blood cells of group B, C and D were significantly lower(P<0.05), while the activities of SOD and GSH-Px were higher than those of group A(P<0.05); and CAT activity in cells treated by ASTA was significantly higher at 28 and 42 days of storage in comparison with that of group A(P<0.05). There were positive correlations between the ROS, MDA content in suspended red blood cells of group A, B, C, D and storage time(P<0.01), while negative correlation between SOD, CAT, GSH-Px activity and storage time(P<0.01). CONCLUSION: ASTA can decrease the oxidative stress level and peroxide damage degree by increasing the antioxidant enzyme activities in suspended leukocyte-depleted red blood cells during storage.


Assuntos
Antioxidantes , Estresse Oxidativo , Catalase/metabolismo , Eritrócitos , Leucócitos , Superóxido Dismutase/metabolismo , Xantofilas
11.
Bioresour Technol ; 341: 125784, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34419876

RESUMO

Haematococcus pluvialis is a commercial microalgae used for natural astaxanthin production. This study aims to investigate the roles of melatonin (MT) and 3-methyladenine (3-MA) in regulating the cell growth and biosynthesis of astaxanthin and fatty acids under adverse conditions by H. pluvialis. Upon the dual treatments, the maximum astaxanthin concentration (46.78 mg L-1) was 2.39- and 1.35-fold higher compared with the control and MT treatments, respectively. Concomitantly, the combined application of MT and 3-MA suppressed autophagy but promoted the production of biomass and lipids and upregulated carotenogenesis, lipogenesis and antioxidant enzyme-related genes at the transcriptional level, which were linked with astaxanthin and lipid biosynthesis and oxidative stress. Additionally, astaxanthin exhibited a noticeable increase under MT coupled with 3-MA in the other two strains of H. pluvialis. This study proposed a potential method for astaxanthin induction and provided insights into the function of autophagy in modulating cell growth and astaxanthin synthesis.


Assuntos
Clorofíceas , Melatonina , Adenina/análogos & derivados , Biomassa , Xantofilas
12.
Bioresour Technol ; 341: 125788, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34461402

RESUMO

Improvement of astaxanthin yield is a continuing objective in Haematococcus pluvialis cultivation. In this study, a new strategy combining exogenous sodium fumarate (SF) with nitrogen deficiency was demonstrated to promote astaxanthin accumulation in H. pluvialis. SF significantly accelerated astaxanthin synthesis over cell growth. Notably, under nitrogen deficiency, 10 mM SF increased the cellular astaxanthin content by 1.75-fold and 1.47-fold on day 7 and 12, respectively. Further studies indicated that SF increased the level of respiratory metabolites in the Embden-Meyerhof-Parnas pathway, tricarboxylic acid cycle and pentose phosphate pathway. An enhanced substrate pool due to the acceleration of respiratory metabolic pathways directly induced astaxanthin synthesis. Meanwhile, the accumulation of C18:1, C18:2 and C18:3 fatty acids enhanced astaxanthin synthesis indirectly by promoting the process of esterification. This study not only helps to elucidate the role of respiratory metabolic pathways in astaxanthin synthesis but also provides a new effective technique to improve astaxanthin production.


Assuntos
Clorofíceas , Clorofíceas/metabolismo , Fumaratos , Redes e Vias Metabólicas , Xantofilas/metabolismo
13.
Molecules ; 26(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34361600

RESUMO

Persistent pollutants such as pharmaceuticals, pesticides, musk fragrances, and dyes are frequently detected in different environmental compartments and negatively impact the environment and humans. Understanding the impacts of diffuse environmental pollutants on plants is still limited, especially at realistic environmental concentrations of contaminants. We studied the effects of key representatives of two major classes of environmental pollutants (nine different antibiotics and six different textile dyes) on the leaf carotenoid (violaxanthin and neoxanthin) content in wheat (Triticum aestivum L.) using different pollutant concentrations and application times. The wheat plants were watered with solutions of selected environmental pollutants in two different concentrations of 0.5 mg L-1 and 1.5 mg L-1 for one week (0.5 L) and two weeks (1 L). Both categories of pollutants selected for this study negatively influenced the content of violaxanthin and neoxanthin, whereas the textile dyes represented more severe stress to the wheat plants. The results demonstrate that chronic exposure to common diffusively spread environmental contaminants constitutes significant stress to the plants.


Assuntos
Antibacterianos/toxicidade , Corantes/toxicidade , Poluentes Ambientais/toxicidade , Folhas de Planta/metabolismo , Triticum/metabolismo , Xantofilas/metabolismo
14.
Molecules ; 26(15)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34361618

RESUMO

Lactic acid fermentation increases the bioactive properties of shrimp waste. Astaxanthin is the principal carotenoid present in shrimp waste, which can be found esterified in the liquid fraction (liquor) after its lactic acid fermentation. Supercritical CO2 technology has been proposed as a green alternative to obtain astaxanthin from fermented shrimp waste. This study aimed to optimize astaxanthin extraction by supercritical CO2 technology from fermented liquor of shrimp waste and study bioaccessibility using simulated gastrointestinal digestion (GD) of the optimized extract. A Box-Behnken design with three variables (pressure, temperature, and flow rate) was used to optimize the supercritical CO2 extraction. The optimized CO2 extract was obtained at 300 bar, 60 °C, and 6 mL/min, and the estimated characteristics showed a predictive extraction yield of 11.17%, antioxidant capacity of 1.965 mmol of Trolox equivalent (TE)/g, and astaxanthin concentration of 0.6353 µg/g. The experiment with optimal conditions performed to validate the predicted values showed an extraction yield of 12.62%, an antioxidant capacity of 1.784 mmol TE/g, and an astaxanthin concentration of 0.52 µg/g. The astaxanthin concentration decreased, and the antioxidant capacity of the optimized extract increased during gastrointestinal digestion. In conclusion, our optimized supercritical CO2 process is suitable for obtaining astaxanthin from shrimp by-products after lactic acid fermentation.


Assuntos
Antioxidantes , Penaeidae/química , Animais , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Dióxido de Carbono/química , Fermentação , Resíduos , Xantofilas/análise , Xantofilas/isolamento & purificação
15.
Appl Microbiol Biotechnol ; 105(16-17): 6133-6142, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34338805

RESUMO

Violaxanthin is biosynthesized from zeaxanthin with zeaxanthin epoxidase (ZEP) by way of antheraxanthin only in photosynthetic eukaryotes including higher plants and involved in the xanthophyll cycle to eliminate excessive light energy. Violaxanthin and antheraxanthin have commercially been unavailable, in contrast to commercial production of other carotenoids contained in higher plants, e.g., lycopene, ß-carotene, lutein, zeaxanthin, ß-cryptoxanthin, and capsanthin. One of the reasons is considered that resource plants or other resource organisms do not exist for enabling efficient supply of the epoxy-carotenoids, which are expected to be produced through (metabolic) pathway engineering with heterologous microbial hosts such as Escherichia coli and Saccharomyces cerevisiae. In this Mini-Review, we show heterologous production of violaxanthin with the two microorganisms that have exhibited significant advances these days. We further describe natural function and occurrence, and biosynthesis involving violaxanthin, antheraxanthin, and their derivatives that include auroxanthin and mutatoxanthin. KEY POINTS: • A comprehensive review on epoxy-carotenoids violaxanthin and antheraxanthin. • Pathway engineering for the epoxy-carotenoids in heterologous microbes. • Our new findings on violaxanthin production with the budding yeast.


Assuntos
Luteína , Xantofilas , Carotenoides , Zeaxantinas
16.
Poult Sci ; 100(9): 101304, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34343906

RESUMO

Long-term and graded dose of astaxanthin supplementation in laying hen's diet was assessed for egg fortification. Five groups of laying hens with 8 replications each were fed for 24 wk with diet supplemented astaxanthin at 0 mg/kg (control), 7.1 mg/kg, 14.2 mg/kg, 21.3 mg/kg, and 42.6 mg/kg (Basal, A7, A14, A21, and A42, respectively). The performance of laying hens, egg quality, astaxanthin concentration as well as conversion efficiency and geometric isomers proportion in yolks were assessed on wk 8 and 24. One-way analysis of variance (ANOVA) and linear and quadratic regression analyses were used to evaluate the dose effect. In parallel, the Student's t test compared the values between wk 8 and wk 24 of test within a group. Overall, the results revealed that neither production performance nor egg physical quality was affected by astaxanthin dose level and feeding duration. Following the supplementation dose, the redness of yolks (a*) increased (P < 0.001). But, the a* score in A42 (23.48) was just 3-folds the a* score in A7 (8.89). Concentration of astaxanthin in eggs was dose-level dependent showing a linear relationship (P < 0.001) with a slight declination observed in all groups on wk 24 compared to wk 8. The deposition rate of astaxanthin into egg yolk was higher in A21 and A42. The proportion of geometric isomers in egg yolk were not affected by the feeding duration. As the supplementation dose increased, all-trans isomer proportion gradually decreased in the egg yolk, while 13-cis isomer proportion rose. It was concluded that astaxanthin is an efficient carotenoid for egg fortification, which can be supplemented in diet up to 42.6 mg/kg for 24 wk without compromising the performance of laying hens or physical quality of eggs. This appreciably affects the egg yolk color and confers a better accumulation of total astaxanthin and cis isomers into eggs as the supplementation dose increases.


Assuntos
Ração Animal , Galinhas , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais , Gema de Ovo , Ovos , Feminino , Óvulo , Xantofilas
17.
Ultrason Sonochem ; 76: 105666, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34271396

RESUMO

This study was aimed at optimizing the astaxanthin extraction efficiency from shrimp shell (green tiger, Penaeus semisulcatus). Astaxanthin was extracted using selected nonpolar/polar solvents (petroleum ether, n-hexane, ethanol, acetone) individually and in ternary mixtures of petroleum ether, acetone, and water in ratios of 15:50:35, 50:45:5, and 15:75:10 for different times (2,4 and 6 h). The results showed that solvents with higher polarity were more suitable for the extraction of astaxanthin, and increasing the extraction time from 2 to 6 h improved the extraction yield. The conditions of extraction of astaxanthin with the desirable solvent were then optimized with the ultrasonic method using the Box-Behnken design [variables included: extraction temperature (25 to 45 °C), extraction time (5 to 15 min), and ultrasound amplitude (20 to 100%)]. Optimal extraction conditions were determined as the ultrasonic amplitude of 23.6%, extraction time of 13.9 min, and extraction temperature of 26.3 °C. Under this optimum condition, the amount of astaxanthin, ferric reducing antioxidant power, and free radical scavenging capacity of the extract were obtained as 51.5%, 1705 µmol of Fe2+/g, and 73.9%, respectively. Extraction and analysis of the extract at the optimum point were used to validate the results.


Assuntos
Exoesqueleto/química , Fracionamento Químico/métodos , Penaeidae/química , Ondas Ultrassônicas , Animais , Temperatura , Fatores de Tempo , Xantofilas/isolamento & purificação
18.
Ultrason Sonochem ; 77: 105671, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34304119

RESUMO

The development of green and sustainable extraction technologies for various naturally active biomaterials is gaining increasing attention due to their environmentally friendly advantages. In this work, the ultrasonic-assisted extraction of fucoxanthin from edible brown algae Sargassum fusiforme using different green solvents was presented. Ethyl lactate, limonene, soybean oil, and sunflower oil were used in place of traditional organic solvents. Ethyl lactate showed similar performance to organic solvents, whereas limonene and vegetable oil exhibited higher selectivity for fucoxanthin. Moreover, the effects of various extraction factors, including liquid/solid ratio, extraction time, extraction temperature, as well as amplitude were studied. The optimal conditions were optimized as follows: liquid/solid ratio, 40 mL/g; extraction time, 27 min; extraction temperature, 75 ℃; amplitude, 53%; and solvent, ethyl lactate. Optimal model of second-order kinetic parameters (rate constant, equilibrium concentration, and initial extraction rate) was successfully developed for describing the dynamic ultrasonic extraction process under different operating conditions.


Assuntos
Modelos Químicos , Sargassum/química , Solventes/química , Ondas Ultrassônicas , Xantofilas/isolamento & purificação , Química Verde , Cinética
19.
Bioresour Technol ; 340: 125648, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34332443

RESUMO

Effects of succinic acid (SA) in fed-batch feeding mode on astaxanthin and lipids biopoduction of Haematococcus pluvialis against abiotic stresses were explored. By comparison with the control, the initial addition of SA on day 0 increased the production of astaxanthin by 71.61%. More importantly, the maximum values of astaxanthin (35.88 mg g-1) and lipid (54.79%) contents were obtained after supplementation of SA on day 7. Meanwhile, under SA treatment, the chlorophyll, carbohydrate, and protein levels were reduced, but the intracellular levels of SA and reactive oxygen species (ROS), the transcription levels of astaxanthin and fatty acids biosynthesis-, and antioxidant system-related genes were increased. Furthermore, scaling-up cultivation in bioreactor further enhanced the astaxanthin productivity from H. pluvialis. Generally, this study proved the intermittent SA feeding method in fed-batch culture as a potent strategy that facilitated massive astaxanthin and lipids production in algae.


Assuntos
Clorofíceas , Ácido Succínico , Lipídeos , Xantofilas
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 262: 120143, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34271237

RESUMO

Astaxanthin (AST) is a xanthophyll carotenoid widely distributed in aquatic animals, which has many physiological functions such as antioxidant, anti-inflammatory, anti-hypertensive and anti-diabetic activities. AST has three optical isomers, including a pair of enantiomers (3S,3'S and 3R,3'R) and a meso form (3R,3'S). Different optical isomers have differences in a variety of physiological functions. Traditionally, High Performance Liquid Chromatography (HPLC) has been used to distinguish these isomers. In this work, it was found that Raman spectroscopy can be employed to distinguish the three optical isomers. The intensities of two Raman bands at 1190 and 1215 cm-1 of three isomers are different. Density Functional Theory (DFT) calculations are performed to analyze the spectral differences. The mainly occupied conformers of these three optical isomers are speculated and identified.


Assuntos
Luteína , Xantofilas , Animais , Carotenoides , Isomerismo , Estereoisomerismo
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