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1.
Mar Drugs ; 22(7)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39057436

RESUMO

The marine kingdom is an important source of a huge variety of scaffolds inspiring the design of new drugs. The complex molecules found in the oceans present a great challenge to organic and medicinal chemists. However, the wide variety of biological activities they can display is worth the effort. In this article, we present an overview of different seaweeds as potential sources of bioactive pigments with activity against neurodegenerative diseases, especially due to their neuroprotective effects. Along with a broad introduction to seaweed as a source of bioactive pigments, this review is especially focused on astaxanthin and fucoxanthin as potential neuroprotective and/or anti-neurodegenerative agents. PubMed and SciFinder were used as the main sources to search and select the most relevant scientific articles within the field.


Assuntos
Doenças Neurodegenerativas , Fármacos Neuroprotetores , Alga Marinha , Xantofilas , Xantofilas/farmacologia , Xantofilas/química , Xantofilas/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Alga Marinha/química , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Animais , Pigmentos Biológicos/farmacologia , Pigmentos Biológicos/química , Pigmentos Biológicos/isolamento & purificação
2.
Braz J Microbiol ; 55(3): 2057-2069, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38775905

RESUMO

This work aimed to evaluate the effects of 4 selected essential oils on planktonic cells and microbial biofilms of the Staphylococcus aureus strain (MRSA ATCC 33591). The antibacterial activities of the four essential oils Geranium (Pelargonium graveolens), PgEO, Tea Tree (Melaleuca alternifolia) MaEO, Lemon peel (Citrus limon) ClEO and Peppermint (Mentha piperita) MpEO had MICs ranging from 1.56 to 12.5 µl/ml. The evaluation of the antibiofilm activities of the 4 EOs revealed that they had antiadhesive activities against S. aureus MRSA biofilms; the activity reached 60% (the EO of MpEO peppermint at a concentration of 3.12 µl/ml), and the eradication activity was 80% (the EO of PgEO and MpEO at 3.12 µl/ml). The antibiofilm activity of S. aureus has been explained by the binding of several essential oil bioactive molecules to the SarA protein, the main target protein involved in biofilm formation. The synthesis of the virulence factor staphyloxanthin by S. aureus MRSA ATCC 33591 was significantly inhibited in the presence of PgEO at a concentration of MIC/2. This inhibition was explained by the binding of the main PgEO molecules (ß-citronellol and geraniol) to the CrTM protein involved in the staphyloxanthin synthesis pathway. There is evidence that these essential oils could be used as potential anti-virulents to control Staphylococcus biofilm formation.


Assuntos
Antibacterianos , Biofilmes , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Óleos Voláteis , Óleos de Plantas , Xantofilas , Biofilmes/efeitos dos fármacos , Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Óleos Voláteis/farmacologia , Xantofilas/farmacologia , Óleos de Plantas/farmacologia , Óleos de Plantas/química , Melaleuca/química , Mentha piperita/química , Pelargonium/química , Geranium/química , Citrus/química
3.
J Food Sci ; 89(6): 3148-3166, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38685866

RESUMO

The global shrimp market holds substantial prominence within the food industry, registering a significant USD 24.7 billion in worldwide exportation in 2020. However, the production of a safe and high-quality product requires consideration of various factors, including the potential for allergenic reactions, occurrences of foodborne outbreaks, and risks of spoilage. Additionally, the exploration of the recovery of bioactive compounds (e.g., astaxanthin [AX], polyunsaturated fatty acids, and polysaccharides) from shrimp waste demands focused attention. Within this framework, this review seeks to comprehend and assess the utilization of high-intensity ultrasound (HIUS), both as a standalone method and combined with other technologies, within the shrimp industry. The objective is to evaluate its applications, limitations, and prospects, with a specific emphasis on delineating the impact of sonication parameters (e.g., power, time, and temperature) on various applications. This includes an examination of undesirable effects and identifying areas of interest for current and prospective research. HIUS has demonstrated promise in enhancing the extraction of bioactive compounds, such as AX, lipids, and chitin, while concurrently addressing concerns such as allergen reduction (e.g., tropomyosin), inactivation of pathogens (e.g., Vibrio parahaemolyticus), and quality improvement, manifesting in reduced melanosis scores and improved peelability. Nonetheless, potential impediments, particularly related to oxidation processes, especially those associated with lipids, pose a hindrance to its widespread implementation, potentially impacting texture properties. Consequently, further optimization studies remain imperative. Moreover, novel applications of sonication in shrimp processing, including brining, thawing, and drying, represent a promising avenue for expanding the utilization of HIUS in the shrimp industry.


Assuntos
Manipulação de Alimentos , Penaeidae , Frutos do Mar , Animais , Penaeidae/química , Penaeidae/microbiologia , Manipulação de Alimentos/métodos , Frutos do Mar/análise , Frutos do Mar/microbiologia , Sonicação/métodos , Xantofilas/análise , Inocuidade dos Alimentos/métodos , Polissacarídeos/análise , Ondas Ultrassônicas
4.
J Sci Food Agric ; 104(10): 5860-5868, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38385790

RESUMO

BACKGROUND: Avocado fruit is rich in xanthophylls, which have been related to positive effects on human health. Xanthophyl acetyltransferases (XATs) are enzymes catalyzing the esterification of carboxylic acids to the hydroxyl group of the xanthophyll molecule. This esterification is thought to increase the lipophilic nature of the xanthophyll and its stability in a lipophilic environment. Studies on XATs in fruits are very scarce, and no studies had been carried out in avocado fruit during postharvest. The objective of this work was to investigate the changes in the expression of genes encoding XAT, during avocado fruit ripening. RESULTS: Avocado fruits were obtained from a local market and stored at 15 °C for 8 days. The fruit respiration rate, ethylene production, and fruit peel's color space parameters (L*, a*, b*) were measured during storage. Fruit mesocarp samples were taken after 1, 3, 5, and 7 days of storage and frozen with liquid nitrogen. Total RNA was extracted from fruit mesocarp, and the quantification of the two genes designated as COGE_ID: 936743791 and COGE_ID: 936800185 encoding XATs was performed with real-time quantitative reverse transcription polymerase chain reaction using actin as a reference gene. The presence of a climacteric peak and large changes in color were recorded during postharvest. The two genes studied showed a large expression after 3 days of fruit storage. CONCLUSIONS: We conclude that during the last stages of ripening in avocado fruit there was an active esterification of xanthophylls with carboxylic acids, which suggests the presence of esterified xanthophylls in the fruit mesocarp. © 2024 Society of Chemical Industry.


Assuntos
Frutas , Regulação da Expressão Gênica de Plantas , Persea , Proteínas de Plantas , Persea/genética , Persea/crescimento & desenvolvimento , Persea/metabolismo , Persea/química , Persea/enzimologia , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Frutas/enzimologia , Frutas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Aciltransferases/genética , Aciltransferases/metabolismo , Armazenamento de Alimentos , Xantofilas/metabolismo , Acetiltransferases/genética , Acetiltransferases/metabolismo
5.
World J Microbiol Biotechnol ; 40(3): 87, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329645

RESUMO

Phaffia rhodozyma is a basidiomycetous yeast characterized by its production of the carotenoid pigment astaxanthin, which holds high commercial value for its significance in aquaculture, cosmetics and as nutraceutics, and the UV-B-absorbing compound mycosporine-glutaminol-glucoside (MGG), which is of great biotechnological relevance for its incorporation into natural sunscreens. However, the industrial exploitation has been limited to the production of astaxanthin in small quantities. On the other hand, the accumulation of MGG in P. rhodozyma was recently reported and could add value to the simultaneous production of both metabolites. In this work, we obtain a mutant strain that overproduces both compounds, furthermore we determined how the accumulation of each is affected by the carbon-to-nitrogen ratio and six biotic and abiotic factors. The mutant obtained produces 159% more astaxanthin (470.1 µg g-1) and 220% more MGG (57.9 mg g-1) than the parental strain (295.8 µg g-1 and 26.2 mg g-1 respectively). Furthermore, we establish that the carotenoids accumulate during the exponential growth phase while MGG accumulates during the stationary phase. The carbon-to-nitrogen ratio affects each metabolite differently, high ratios favoring carotenoid accumulation while low ratios favoring MGG accumulation. Finally, the accumulation of both metabolites is stimulated only by photosynthetically active radiation and low concentrations of hydrogen peroxide. The mutant strain obtained is the first hyper-productive mutant capable of accumulating high concentrations of MGG and astaxanthin described to date. The characterization of how both compounds accumulate during growth and the factors that stimulate their accumulation, are the first steps toward the future commercial exploitation of strains for the simultaneous production of two biotechnologically important metabolites.


Assuntos
Basidiomycota , Técnicas de Cultura Celular por Lotes , Carotenoides , Carbono , Glucosídeos , Nitrogênio , Xantofilas
6.
Appl Microbiol Biotechnol ; 108(1): 158, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38252271

RESUMO

Astaxanthin is one of the most attractive carotenoids due to its high antioxidant activity and beneficial biological properties, while Xanthophyllomyces dendrorhous is one of its main microbial sources. Since astaxanthin is synthesized as a response to oxidative stress, several oxidative agents have been evaluated to increase X. dendrorhous astaxanthin yields. However, the extent of the stimulation is determined by the cellular damage caused by the applied oxidative agent. Phytohormones have also been reported as stimulants of astaxanthin biosynthesis acting directly on its metabolic pathway and indirectly promoting cellular resistance to reactive oxygen species. We reasoned that both oxidative agents and phytohormones lead to increased astaxanthin synthesis, but the latter could mitigate the drawbacks of the former. Thus, here, the stimulation on astaxanthin biosynthesis, as well as the cellular and transcriptional responses of wild type X. dendrorhous to phytohormones (6-benzylaminopurine, 6-BAP; abscisic acid, ABA; and indole-3-acetic acid, IAA), and oxidative agents (glutamate, menadione, H2O2, and/or Fe2+) were evaluated as a single or combined treatments. ABA and 6-BAP were the best individual stimulants leading to 2.24- and 2.60-fold astaxanthin biosynthesis increase, respectively. Nevertheless, the effect of combined 6-BAP and H2O2 led to a 3.69-fold astaxanthin synthesis increase (0.127 ± 0.018 mg astaxanthin/g biomass). Moreover, cell viability (> 82.75%) and mitochondrial activity (> 82.2%) remained almost intact in the combined treatment (6-BAP + H2O2) compared to control (< 52.17% cell viability; < 85.3% mitochondrial activity). On the other hand, mRNA levels of hmgR, idi, crtYB, crtR, and crtS, genes of the astaxanthin biosynthetic pathway, increased transiently along X. dendrorhous fermentation due to stimulations assayed in this study. KEY POINTS: • Combined 6-BAP and H2O2 is the best treatment to increase astaxanthin yields in X. dendrorhous. • 6-BAP preserves cell integrity under oxidative H2O2 stress conditions. • 6-BAP and H2O2 increase transcriptional responses of hmgR, idi, and crt family genes transiently.


Assuntos
Basidiomycota , Compostos de Benzil , Estimulantes do Sistema Nervoso Central , Reguladores de Crescimento de Plantas , Purinas , Peróxido de Hidrogênio , Xantofilas
7.
Biochim Biophys Acta Biomembr ; 1866(3): 184288, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38286247

RESUMO

Staphylococcus aureus is an opportunistic pathogen that is considered a global health threat. This microorganism can adapt to hostile conditions by regulating membrane lipid composition in response to external stress factors such as changes in pH and ionic strength. S. aureus synthesizes and incorporates in its membrane staphyloxanthin, a carotenoid providing protection against oxidative damage and antimicrobial agents. Staphyloxanthin is known to modulate the physical properties of the bacterial membranes due to the rigid diaponeurosporenoic group it contains. In this work, preparative thin layer chromatography and liquid chromatography mass spectrometry were used to purify staphyloxanthin from S. aureus and characterize its structure, identifying C15, C17 and C19 as the main fatty acids in this carotenoid. Changes in the biophysical properties of models of S. aureus membranes containing phosphatidylglycerol, cardiolipin, and staphyloxanthin were evaluated. Infrared spectroscopy shows that staphyloxanthin reduces the liquid-crystalline to gel phase transition temperature in the evaluated model systems. Interestingly, these shifts are not accompanied by strong changes in trans/gauche isomerization, indicating that chain conformation in the liquid-crystalline phase is not altered by staphyloxanthin. In contrast, headgroup spacing, measured by Laurdan GP fluorescence spectroscopy, and lipid core dynamics, measured by DPH fluorescence anisotropy, show significant shifts in the presence of staphyloxanthin. The combined results show that staphyloxanthin reduces lipid core dynamics and headgroup spacing without altering acyl chain conformations, therefore decoupling these normally correlated effects. We propose that the rigid diaponeurosporenoic group in staphyloxanthin and its positioning in the membrane is likely responsible for the results observed.


Assuntos
Staphylococcus aureus , Xantofilas , Staphylococcus aureus/fisiologia , Xantofilas/química , Carotenoides , Fosfatidilgliceróis
8.
J Chemother ; 36(3): 222-237, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37800867

RESUMO

Countless efforts have been made to prevent and suppress the formation and spread of melanoma. Natural astaxanthin (AST; extracted from the alga Haematococcus pluvialis) showed an antitumor effect on various cancer cell lines due to its interaction with the cell membrane. This study aimed to characterize the antitumor effect of AST against B16F10-Nex2 murine melanoma cells using cell viability assay and evaluate its mechanism of action using electron microscopy, western blotting analysis, terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay, and mitochondrial membrane potential determination. Astaxanthin exhibited a significant cytotoxic effect in murine melanoma cells with features of apoptosis and autophagy. Astaxanthin also decreased cell migration and invasion in vitro assays at subtoxic concentrations. In addition, assays were conducted in metastatic cancer models in mice where AST significantly decreased the development of pulmonary nodules. In conclusion, AST has cytotoxic effect in melanoma cells and inhibits cell migration and invasion, indicating a promising use in cancer treatment.


Assuntos
Antineoplásicos , Melanoma Experimental , Camundongos , Animais , Linhagem Celular Tumoral , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Apoptose , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Autofagia , Proliferação de Células , Camundongos Endogâmicos C57BL , Xantofilas
9.
Appl Microbiol Biotechnol ; 107(13): 4199-4215, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37233757

RESUMO

The attractive biological properties and health benefits of natural astaxanthin (AXT), including its antioxidant and anti-carcinogenic properties, have garnered significant attention from academia and industry seeking natural alternatives to synthetic products. AXT, a red ketocarotenoid, is mainly produced by yeast, microalgae, wild or genetically engineered bacteria. Unfortunately, the large fraction of AXT available in the global market is still obtained using non-environmentally friendly petrochemical-based products. Due to the consumers concerns about synthetic AXT, the market of microbial-AXT is expected to grow exponentially in succeeding years. This review provides a detailed discussion of AXT's bioprocessing technologies and applications as a natural alternative to synthetic counterparts. Additionally, we present, for the first time, a very comprehensive segmentation of the global AXT market and suggest research directions to improve microbial production using sustainable and environmentally friendly practices. KEY POINTS: • Unlock the power of microorganisms for high value AXT production. • Discover the secrets to cost-effective microbial AXT processing. • Uncover the future opportunities in the AXT market.


Assuntos
Antioxidantes , Engenharia Genética , Xantofilas , Leveduras
10.
Crit Rev Food Sci Nutr ; 63(13): 1862-1876, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34433348

RESUMO

Astaxanthin (AXT) is a natural xanthophyll with strong antioxidant, anticancer and antimicrobial activities, widely used in the food, feed, pharmaceutical and nutraceutical industries. So far, 95% of the AXT global market is produced by chemical synthesis, but growing customer preferences for natural products are currently changing the market for natural AXT, highlighting the production from microbially-based sources such as the yeast Phaffia rhodozyma. The AXT production by P. rhodozyma has been studied for a long time at a laboratory scale, but its use in industrial-scale processes is still very scarce. The optimization of growing conditions as well as an effective integration of upstream-downstream operations into P. rhodozyma-based AXT processes has not yet been fully achieved. With this critical review, we scrutinized the main approaches for producing AXT using P. rhodozyma strains, highlighting the impact of using conventional and non-conventional procedures for the extraction of AXT from yeast cells. In addition, we also pinpointed research directions, for example, the use of low-cost residues to improve the economic and environmental sustainability of the bioprocess, the use of environmentally/friendly and low-energetic integrative operations for the extraction and purification of AXT, as well as the need of further human clinical trials using yeast-based AXT.


Assuntos
Basidiomycota , Saccharomyces cerevisiae , Humanos , Xantofilas , Biotecnologia , Basidiomycota/química
11.
Crit Rev Biotechnol ; 43(4): 540-558, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35430937

RESUMO

The demand for food, feed, cosmeceutical, and nutraceutical supplements/additives from natural sources has been rapidly increasing, with expectations for a faster expansion than the growth of the global markets in the coming years. In this framework, a particular interest is given to carotenoids due to their outstanding antioxidant activities, particularly the xanthophylls class. Torularhodin is one of these carotenoids that stands out for its multifunctional role as: antioxidant, anticancer and antimicrobial, yet its commercial potential is still unexplored. Although most xanthophylls can be naturally found in: microbial, plant and animal sources, torularhodin is only produced by microbial species, especially red oleaginous yeast. The microbial production of xanthophylls has many advantages as compared to other natural sources, such as: the need for low production area, easier extraction, high yields (at optimum operating conditions), and low (or no) seasonal, climatic, and geographic variation dependency. Due to the importance of natural products and their relevance to the market, this review provides a comprehensive overview of the: properties, characteristics and potential health benefits of torularhodin. Moreover, the most promising developments in both upstream and downstream processing to obtain this colorant from microbial sources are considered. For this purpose, the main microorganisms used for torularhodin production are firstly reviewed, including biosynthesis pathway and torularhodin properties. Following, an overall analysis of the processing aspects related with its: extraction, separation and purification is provided. Lastly, current status and future trends of torularhodin-based processes and products such as therapeutic agents or biomaterials are discussed, indicating promising directions toward biorefinery and circular economy.


Assuntos
Antioxidantes , Carotenoides , Animais , Xantofilas
12.
Bioresour Technol ; 361: 127706, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35905884

RESUMO

The study evaluated the techno-economic feasibility of an industrial SFE plant to produce astaxanthin-rich extracts in Chile based on previously published data. A kinetic study comparing two solvent flow rates (3.62 and 7.24 g/min) at a scale production of 2 × 10 L showed the FER period as the more economically feasible with a cost of manufacturing (COM) of US$ 656.31/kg at 7.24 g/min. The study also demonstrated that the extraction times used at a laboratory scale were not industrially feasible due to the flowrate limits of industrial pumps. After adjusting extraction time to real industrial conditions, the results demonstrated that a 5-fold scale increase (2 × 10 L to 2 × 50 L) decreased the COM by 30 % and the process was profitable at all production scales. Finally, the sensitivity study demonstrated that it is possible to reduce the selling price by 25 % at 2 × 50 L scale.


Assuntos
Clorofíceas , Cromatografia com Fluido Supercrítico , Cromatografia com Fluido Supercrítico/métodos , Solventes , Xantofilas
13.
Sci Total Environ ; 841: 156795, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35732235

RESUMO

Flocculation has been proved an efficient method for microalgal biomass harvesting, but some coagulant agents may have adverse effects on microalgae growth, making the reuse of the medium unfeasible. In this study, Haematococcus pluvialis was harvested by different flocculants, and the feasibility of the reuse of the culture medium was evaluated. Results suggested that both inorganics, polyaluminum chloride (PA) and ferric chloride (FC), and organics, extracted from Moringa oleifera seed (MSE) and chitosan (CH) resulted in efficient flocculation - flocculation efficiency above 99 %. However, using PA and FC had adverse effects on the astaxanthin recovery from haematocysts - losses of 58.6 and 73.5 %, respectively. Bioflocculants in the reused medium also had higher growth performance than inorganic ones. Furthermore, bioflocculants in reused medium increase the contents of ß-carotene, astaxanthin, and linolenic acid. This investigation demonstrated that using MSE and CHI for harvesting H. pluvialis enables the water reusability from a flocculated medium.


Assuntos
Clorofíceas , Microalgas , Biomassa , Floculação , Água , Xantofilas
14.
Braz J Otorhinolaryngol ; 88 Suppl 3: S73-S80, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35331657

RESUMO

OBJECTIVE: Diabetes Mellitus (DM) causes an increase in oxidative stress that leads to deterioration in auditory functions. Astaxanthine (AST) is known to have strong antioxidant effects. In this study, the aim is to investigate the effect of AST against hearing loss that is due to DM. METHODS: This study is an experimental animal study. The study was designed in four groups with 8 animals (n = 8) in each group. The groups were as follows; Control Group (CNT), Diabetic Group (DM), AST applied diabetic group (DM+AST), and AST applied non-diabetic group (AST). Streptozotocin was applied in rats to induce DM. AST was administered by oral gavage. Auditory Brainstem Responses (ABR) and Distortion Product Otoacoustic Emissions (DPOAE) tests were performed on several days of the study. At the end of the study, pro-inflammatory cytokine levels were analyzed in cochlear tissue samples, and Glutathione Peroxidase (GPx), Superoxide Dismutase (SOD), Catalase (CAT) and Malondialdehyde (MDA) levels were measured. RESULTS: When the findings obtained in the ABR and DPOAE tests in the DM group, it was observed that there was a significant deterioration in the hearing sense. This deterioration was not observed in the DM+AST group. In the DM group, GPx, SOD and CAT levels decreased and MDA levels increased in blood and cochlear tissue. Compared to the DM group, it was noted that antioxidant enzyme levels increased and MDA levels decreased in the DM+AST group. Cochlear tissue pro-inflammatory cytokine levels, which increased with DM, were significantly decreased in the DM+AST group. CONCLUSION: Even though the effects of AST were investigated in a diabetic experimental animal model, if this molecule is proven to be effective in diabetic humans, it can be considered an adjunct therapeutic option with its antioxidant effects. LEVEL OF EVIDENCE: The level of evidence of this article is 5. This article is an experimental animal and laboratory study.


Assuntos
Diabetes Mellitus Experimental , Perda Auditiva , Xantofilas , Animais , Ratos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Citocinas , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Glutationa Peroxidase/metabolismo , Perda Auditiva/tratamento farmacológico , Perda Auditiva/etiologia , Perda Auditiva/prevenção & controle , Superóxido Dismutase , Xantofilas/uso terapêutico
15.
Mar Drugs ; 20(2)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35200656

RESUMO

Phaeodactylum tricornutum is the marine diatom best known for high-value compounds that are useful in aquaculture and food area. In this study, fucoxanthin was first extracted from the diatom using supercritical fluid extraction (SFE) and then using the extracted diatom-like substrate to produce bioenergy through anaerobic digestion (AD) processes. Factors such as temperature (30 °C and 50 °C), pressure (20, 30, and 40 MPa), and ethanol (co-solvent concentration from 10% to 50% v/v) were optimized for improving the yield, purity, and recovery of fucoxanthin extracted using SFE. The highest yield (24.41% w/w) was obtained at 30 MPa, 30 °C, and 30% ethanol but the highest fucoxanthin purity and recovery (85.03mg/g extract and 66.60% w/w, respectively) were obtained at 30 MPa, 30 °C, and 40%ethanol. Furthermore, ethanol as a factor had the most significant effect on the overall process of SFE. Subsequently, P.tricornutum biomass and SFE-extracted diatom were used as substrates for biogas production through AD. The effect of fucoxanthin was studied on the yield of AD, which resulted in 77.15 ± 3.85 LSTP CH4/kg volatile solids (VS) and 56.66 ± 1.90 LSTP CH4/kg VS for the whole diatom and the extracted P.tricornutum, respectively. Therefore, P.tricornutuman can be considered a potential source of fucoxanthin and methane and both productions will contribute to the sustainability of the algae-biorefinery processes.


Assuntos
Biocombustíveis , Diatomáceas/metabolismo , Xantofilas/isolamento & purificação , Anaerobiose/fisiologia , Biomassa , Cromatografia com Fluido Supercrítico/métodos , Etanol/química , Solventes/química , Temperatura
17.
J Sci Food Agric ; 102(10): 4287-4295, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35038166

RESUMO

BACKGROUND: Astaxanthin, classified as a xanthophyll, has antioxidant properties about 500 times greater than α-tocopherols and ten times greater than ß-carotenes. Based on the antioxidant activity of this carotenoid, this study aimed to evaluate the shelf-life of tilapia fillets (Oreochromis niloticus) fed with astaxanthin, by determining the microbiological quality (colimetry, counts of mesophilic and psychrotrophic microorganisms), physicochemical analyses (colorimetry, pH, thiobarbituric acid reactive substances (TBARS)) and sensory analysis. RESULTS: Tilapia supplemented with astaxanthin presented a reduction in the counts of microorganisms (mesophiles and psychrotrophics) and lower lipid oxidation index (TBARS), when compared to fillets of control fish. Colorimetric changes of fillet degradation were observed, associated with increased pH during storage, as well as loss of brightness and texture in addition to worsening of appearance and odor. These deteriorating changes were minimized using astaxanthin. CONCLUSION: Our results demonstrate the beneficial performance of astaxanthin in the shelf-life of tilapia fillets stored under refrigeration. Therefore, dietary supplementation with astaxanthin (100 and 200 mg kg-1 of feed) improves the microbiological and physicochemical quality of tilapia fillets during 50 days of shelf-life. © 2022 Society of Chemical Industry.


Assuntos
Tilápia , Animais , Conservação de Alimentos/métodos , Refrigeração , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Xantofilas/análise
18.
Prep Biochem Biotechnol ; 52(5): 598-609, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34424829

RESUMO

Astaxanthin is a xanthophyll carotenoid widely used in aquaculture and nutraceutical industries. Among natural sources, the microalga Haematococcus pluvialis is the non-genetically modified organism with the greatest capacity to accumulate astaxanthin. Therefore, it is important to understand emerging strategies in upstream and downstream processing of astaxanthin from this microalga. This review covers all aspects regarding the production and the market of natural astaxanthin from H. pluvialis. Astaxanthin biosynthesis, metabolic pathways, and nutritional metabolisms from the green vegetative motile to red hematocyst stage were reviewed in detail. Also, traditional and emerging techniques on biomass harvesting and astaxanthin recovery were presented and evaluated. Moreover, the global market of astaxanthin was discussed, and guidelines for sustainability increasing of the production chain of astaxanthin from H. pluvialis were highlighted, based on biorefinery models. This review can serve as a baseline on the current knowledge of H. pluvialis and encourage new researchers to enter this field of research.


Assuntos
Clorofíceas , Microalgas , Biomassa , Microalgas/metabolismo , Xantofilas
19.
Int J Mol Sci ; 22(24)2021 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-34948418

RESUMO

Coloring is one of the most important characteristics in commercial flowers and fruits, generally due to the accumulation of carotenoid pigments. Enzymes of the CCD4 family in citrus intervene in the generation of ß-citraurin, an apocarotenoid responsible for the reddish-orange color of mandarins. Citrus CCD4s enzymes could be capable of interacting with the thylakoid membrane inside chloroplasts. However, to date, this interaction has not been studied in detail. In this work, we present three new complete models of the CCD4 family members (CCD4a, CCD4b, and CCD4c), modeled with a lipid membrane. To identify the preference for substrates, typical carotenoids were inserted in the active site of the receptors and the protein-ligand interaction energy was evaluated. The results show a clear preference of CCD4s for xanthophylls over aliphatic carotenes. Our findings indicate the ability to penetrate the membrane and maintain a stable interaction through the N-terminal α-helical domain, spanning a contact surface of 2250 to 3250 Å2. The orientation and depth of penetration at the membrane surface suggest that CCD4s have the ability to extract carotenoids directly from the membrane through a tunnel consisting mainly of hydrophobic residues that extends up to the catalytic center of the enzyme.


Assuntos
Carotenoides/metabolismo , Citrus/metabolismo , Dioxigenases/metabolismo , Proteínas de Plantas/metabolismo , Carotenoides/química , Citrus/química , Dioxigenases/química , Modelos Moleculares , Proteínas de Plantas/química , Ligação Proteica , Domínios Proteicos , Especificidade por Substrato , Xantofilas/química , Xantofilas/metabolismo
20.
Molecules ; 26(20)2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34684678

RESUMO

BACKGROUND: The blockade of the progression or onset of pathological events is essential for the homeostasis of an organism. Some common pathological mechanisms involving a wide range of diseases are the uncontrolled inflammatory reactions that promote fibrosis, oxidative reactions, and other alterations. Natural plant compounds (NPCs) are bioactive elements obtained from natural sources that can regulate physiological processes. Inflammation is recognized as an important factor in the development and evolution of chronic renal damage. Consequently, any compound able to modulate inflammation or inflammation-related processes can be thought of as a renal protective agent and/or a potential treatment tool for controlling renal damage. The objective of this research was to review the beneficial effects of bioactive natural compounds on kidney damage to reveal their efficacy as demonstrated in clinical studies. METHODS: This systematic review is based on relevant studies focused on the impact of NPCs with therapeutic potential for kidney disease treatment in humans. RESULTS: Clinical studies have evaluated NPCs as a different way to treat or prevent renal damage and appear to show some benefits in improving OS, inflammation, and antioxidant capacity, therefore making them promising therapeutic tools to reduce or prevent the onset and progression of KD pathogenesis. CONCLUSIONS: This review shows the promising clinical properties of NPC in KD therapy. However, more robust clinical trials are needed to establish their safety and therapeutic effects in the area of renal damage.


Assuntos
Nefropatias/tratamento farmacológico , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Antioxidantes/farmacologia , Berberina/farmacologia , Beta vulgaris , Betalaínas/farmacologia , Produtos Biológicos/farmacologia , Catequina/farmacologia , Curcumina/farmacologia , Dissulfetos/farmacologia , Flavonoides/farmacologia , Humanos , Isotiocianatos/farmacologia , Rim/efeitos dos fármacos , Rim/patologia , Punica granatum , Resveratrol/farmacologia , Ácidos Sulfínicos/farmacologia , Sulfóxidos/farmacologia , Xantofilas/farmacologia
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