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This study proposes a method for the ultrasonic extraction of carotenoids and chlorophyll from Scenedesmus obliquus and Arthrospira platensis microalgae with green solvents. Ethanol and ethanolic solutions of ionic liquids were tested with a variety of extraction parameters, including number of extractions, time of extraction, and solid-liquid ratio R(S/L), to determine the optimal conditions. After selecting the most effective green solvent (ethanol), the process conditions were established: R(S/L) of 1:10, three extraction cycles at 3 min each), giving an extraction yield of 2602.36 and 764.21 µgcarotenoids.gdried biomass-1; and 22.01 and 5.81 mgchlorophyll.gdried biomass-1 in S. obliquus and A. platensis, respectively. The carotenoid and chlorophyll extracts obtained using ethanol were shown to be potent scavengers of peroxyl radical, being 5.94 to 26.08 times more potent α-tocopherol. These findings pave the way for a green strategy for valorizing microalgal biocompounds through efficient and environmentally friendly technological processes.
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Carotenoides , Clorofila , Química Verde , Microalgas , Scenedesmus , Solventes , Carotenoides/isolamento & purificação , Carotenoides/química , Microalgas/química , Clorofila/química , Clorofila/isolamento & purificação , Solventes/química , Scenedesmus/química , Scenedesmus/crescimento & desenvolvimento , Spirulina/química , Ultrassom , Fracionamento Químico/métodosRESUMO
BACKGROUND: The decarbonization of road transport is a precondition for achieving carbon neutrality. Battery-electric vehicle technology can make this a reality. In this bias, the objective of the article is to shed light on the ongoing debate about the potentially important role of the adoption of electric vehicles in the transport of microalgae- based products to help them advance to a cleaner life cycle. METHODS: Five routes, including unimodal and multimodal conditions, were defined to assess the carbon emissions of the transport system and, more specifically, of road transport. The headquarters of market-leading microalgae manufacturers were selected as the origin of the routes and, as the destination, regions that sustain them. RESULTS: The results reveal the supremacy of road transport of microalgae-based products using electric vehicles powered by nuclear, hydroelectric, and wind, followed by biomass and photovoltaic energy. They also show that the positive impact of wind, water, and photovoltaic energy on the climate, added to the lower battery charging costs and the greater opportunity to generate revenue from the sale of carbon credits, make their tradeoffs. CONCLUSION: The exquisite results of this study convey key messages to decision-makers and stakeholders about the role of electromobility in building a zero-carbon delivery route.
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Light energy directly affects microalgae growth and productivity. Microalgae in natural environments receive light through solar fluxes, and their duration and distribution are highly variable over time. Consequently, microalgae must adjust their photosynthetic processes to avoid photo limitation and photoinhibition and maximize yield. Considering these circumstances, adjusting light capture through artificial lighting in the main culture systems benefits microalgae growth and induces the production of commercially important compounds. In this sense, this review provides a comprehensive study of the role of light in microalgae biotechnology. For this, we present the main fundamentals and reactions of metabolism and metabolic alternatives to regulate photosynthetic conversion in microalgae cells. Light conversions based on natural and artificial systems are compared, mainly demonstrating the impact of solar radiation on natural systems and lighting devices, spectral compositions, periodic modulations, and light fluxes when using artificial lighting systems. The most commonly used photobioreactor design and performance are shown herein, in addition to a more detailed discussion of light-dependent approaches in these photobioreactors. In addition, we present the principal advances in photobioreactor projects, focusing on lighting, through a patent-based analysis to map technological trends. Lastly, sustainability and economic issues in commercializing microalgae products were presented.
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Microalgas , Patentes como Assunto , Biotecnologia , Meio AmbienteRESUMO
Several medicinal plants have been administered to cancer patients attributed to their anticarcinogenic and chemoprotective properties, in addition to lower toxicity compared to traditional therapies. The aim was to investigate the antioxidant properties and carotenoid composition of aqueous extracts of Mentha piperita or Artemisia vulgaris which were previously found to exert beneficial effects on human health through diet. aqueous extracts exhibited potent antioxidant activity. A diversity of carotenoids was identified in these extracts using HPLC-PDA-MS/MS. Both extracts contained predominantly all-trans-lutein as the main component within this class. In order to investigate antioxidant properties, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) techniques were used. The (3-4,5 dimethylthiazol-2, 5 diphenyl tetrazolium bromide) (MTT) and Crystal Violet assays assessed cellular cytotoxicity. Assessments of presence of reactive species were carried out following exposure of oral squamous cell carcinoma cell line (SCC-4) to various aqueous extracts of M piperita or A vulgaris utilizing dichlorofluorescein diacetate (DCFH-DA) and nitric oxide (NO) assays. Exposure to these extracts induced severe cytotoxic effects, which led to investigation of the biochemical and molecular mechanisms underlying this observed effect. Data demonstrated that both solutions induced oxidative stress and DNA damage, especially at higher concentrations using agarose gel subjected to electrophoresis. It is known that exposure to excess amounts of antioxidants results in a prooxidant effect which is beneficial in cancer therapy. Further, the extracts were found to reduce viability of SCC-4 in culture, indicating that this antitumoral activity may be of therapeutic importance and requires further study.
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Artemisia , Carcinoma de Células Escamosas , Neoplasias Bucais , Humanos , Antioxidantes/farmacologia , Antioxidantes/química , Mentha piperita/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Espectrometria de Massas em Tandem , Clivagem do DNA , Compostos Fitoquímicos , Carotenoides/farmacologiaRESUMO
Color is a crucial sensory attribute that guides consumer expectations. A high-performance pequi carotenoid extraction process was developed using ionic liquid-based ethanolic solutions and a factorial design strategy to search for a potential substitute for the artificial azo dye yellow tartrazine. All-trans-antheraxanthin was identified with HPLC-PAD-MSn for the first time in pequi samples. [BMIM][BF4] was the most efficient ionic liquid, and the maximization process condition was the solid-liquid ratio R(S/L) of 1:3, the co-solvent ratio R(IL/E) of 1:1 ([BMIM][BF4]: ethanol), and three cycles of extraction with 300 s each and yielded 107.90 µg carotenoids/g of dry matter. The ionic liquid-ethanolic solution recyclability was accomplished by freezing and precipitating with an average recovery of 79 %. In CIELAB parameters, pequi carotenoid extracted with [BMIM][BF4] was brighter and yellower than the artificial azo dye yellow tartrazine. A color change of 11.08 and a hue* difference of 1.26° were obtained. Furthermore, carotenoids extracted with [BMIM][BF4] showed antioxidant activity of 35.84 µmol of α-tocopherol. These findings suggest the potential of employing the pequi carotenoids to replace the artificial azo dye yellow tartrazine in foods for improved functional properties.
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Líquidos Iônicos , Tartrazina , Compostos Azo , Carotenoides , AntioxidantesRESUMO
The particular plant species found in southern Brazil, Vassobia breviflora (Solanaceae) has only a few apparent studies examining its biological effect. Thus, the aim of the present study was to determine the activity of the acetone extract fraction derived from V. breviflora. Four compounds were identified by ESI-qTOF-MS: eucalrobusone R, aplanoic acid B, pheophorbide A, and pheophytin A. In addition, 5 compounds were identified by HPLC-PDA-MS/MS: all-trans-lutein, 15-cis-lutein, all-trans-ß-carotene, 5,8-epoxy-ß-carotene, and cis-ß-carotene. Cell lines A549 (lung cancer), A375 (melanoma cancer) and HeLa (cervical cancer) were incubated with different concentrations of each studied extract using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), and 2'-7'dichlorofluorescin diacetate (DCFH-DA) assays. The acetonic extract exhibited cytotoxic activity at a concentration of 0.03 mg/ml in the HeLa strain and 0.1 mg/ml in the others. In addition to increased production of reactive oxygen species (ROS). Antibacterial activity was assessed utilizing minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) in 9 ATCCs strains and 7 clinical isolates, as well as determination of biofilm production. Data demonstrated that MIC and MBC were approximately 256 mg/ml in most of the strains tested and antibiofilm effect at S. aureus, S. epidermidis, A. baumannii, and E. faecalis, concentrations below the MIC. Genotoxic activity on plasmid DNA did not produce significant elevated levels in breaks in the isolated genetic material.
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Acetona , Luteína , Staphylococcus aureus , Espectrometria de Massas em Tandem , beta Caroteno , BrasilRESUMO
Microalgae are photosynthetic microorganisms that stand out from conventional food sources and ingredients due to their high growth rate and adaptability. In addition to being highly sustainable, significant concentrations of proteins, lipids, and pigments accumulate in their cell structures from photosynthesis. Hence, this study sought to evaluate the food potential of Scenedesmus obliquus biomasses obtained from photosynthetic cultures enriched with 3, 5, 10, 15, 20, and 25% carbon dioxide (CO2) (v/v). Cultivations with 3, 5, and 10% CO2 showed greater amino acids and proteins synthesis; the protein content reached values above 56% of the dry biomass and high protein quality, due to the presence of most essential amino acids at recommended levels for the human diet. The highest concentrations of chlorophylls were found in cultures with 15, 20, and 25% CO2 (24.2, 23.1 and 30.8 mg g-1, respectively), although the profiles showed higher percentages of degradation compounds. Carotenoid concentrations were three times higher in cultures with 3, 5, and 10% CO2 (25.3, 22.7 and 18.1 mg g-1, respectively) and all-trans-ß-carotene was the major compound. Lipid synthesis was intensified at higher CO2 enrichment; the percentages obtained were 14.8% of lipids in the culture with 15% CO2, 15.0% with 20% CO2, and 13.7% with 25% CO2. In addition, greater polyunsaturated fatty acids accumulation and a significant reduction in the n6/n3 ratio were also observed at the highest CO2 concentrations. Our findings showed that CO2 treatments significantly altered all compounds concentrations in S. obliquus biomasses, which presented satisfactory composition for application in foods and as ingredients.
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Clorofíceas , Scenedesmus , Biomassa , Dióxido de Carbono/metabolismo , Clorofíceas/metabolismo , Humanos , Lipídeos , Fotossíntese , Scenedesmus/metabolismoRESUMO
The objective of this work was to evaluate the effect of different photo-cycles on the growth and biochemical profile of Scenedesmus obliquus CPCC05, focusing on food interest compounds. The photo-cycle conditions were separated into three groups: long-term photo-cycles (24:0, 22:2, 20:4, 18:6, 12:12, and 10:14 (h:h)), frequency photo-cycles (2, 4, 8, 12, 24, and 48 times per day (t/d)), and short photo-cycles (0.91:0.09, 0.83:0.17, 0.75:0.25, and 0.50:0.50 (s:s)) of light:dark, respectively. The results showed these microalgae can store enough energy to support cell growth for continuous periods of up to 2 h in the dark, without affecting the productivity of the process. This 2 h, when divided into 2 cycles per day (2 t/d), showed the best growth condition (3700 mg L-1), generation time (14.40 h), and maximum biomass productivity (21.43 mg L h-1). This photo-cycle of 2 t/d was also the best condition for the production of total sterols. However, the values of polyunsaturated fatty acids, lipid content, and amino acids obtained higher yields in the short photo-cycle of 0.75:0.25. Thus, the modulation of light cycles becomes an important tool for boosting and directing the production of target molecules in phototrophic cultures of microalgae.
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In this work was to develop an inedited nanocapsule with tucumã oil (Astrocaryum vulgare). The oil presents of phytosterols (squalene and ß-sitosterol), all-trans-beta-carotene, acids oleic and palmitic. Antioxidant activity showed a good performance in DPPH and ABTS assays. The nanocapsules were prepared and demonstrated in their characterization particle size (206 ± 0.69 nm). The cytogenotoxicity evaluation was performed using the MTT, dichlorofluorescein, nitric oxide and dsDNA PicoGreen® assays. Antitumor efficacy assays in MCF-7 cells demonstrated that free oil and tucumã nanocapsules had IC50 of 130 and 50 µg/mL, respectively. Thus, previous studies of toxicity are relevant, as they generate future subsidies, aiming at the potential application of nanostructures and in addition, the promising effect of NCs of tucumã oil on the antiproliferative effect in breast adenocarcinoma cells was evidenced.
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Antioxidantes/farmacologia , Arecaceae/química , Nanocápsulas/química , Compostos Fitoquímicos/farmacologia , Óleos de Plantas/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/análise , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Tamanho da Partícula , Compostos Fitoquímicos/análise , Fitosteróis/análise , Óleos de Plantas/químicaRESUMO
Sterol analysis of complex matrices can be very laborious. To minimize the existing drawbacks, a new micro-method of sterols and squalene determination in cyanobacteria was developed and applied to monitor their production of Phormidium autumnale cultured heterotrophically. Sample extraction/saponification and GC analysis of the target compounds were optimized separately using Plackett-Burman design (PB) followed by a central composite rotational design (CCRD). The most influential variables were identified to maximize compound recovery. Chloroform presented the highest capability to extract all target compounds with a horizontal shaker table (HST) for homogenization in the saponification step. For the pretreatment, a small amount of chloroform was used for 90 min at 50 °C and 6 min for the saponification time. The sample introduction in the GC injector was studied by evaluating pressure and injector temperature. High response for sterols and squalene were obtained between 19 and 23 psi and at 310 °C of injection temperature. The new method was able to determine different sterol concentrations: 0.2-0.6 mg kg-1 of squalene, 5-18 mg kg-1 of stigmasterol, 6 mg kg-1 of cholesterol, and 3 mg kg-1 of ß-sitosterol, showing high analytical performance and fulfilling all steps, thus proving to be a promising technique.
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Cianobactérias , Esteróis , Biomassa , Cromatografia Gasosa , Esqualeno/análiseRESUMO
Cyanobacteria and microalgae are characterized by a rich and varied profile of chlorophyll (8-20 mg/g) and carotenoid (>2.2 mg/g) pigments, being noteworthy material for natural pigment production in the food industry. We propose a systematic workflow that uses high-performance liquid chromatography (HPLC) coupled with high-resolution tandem mass spectrometry in a broadband collision-induced dissociation mode (bbCID) acquisition mode to simultaneously obtain MS and MSn spectra. Metabolomic studies showed for the first time the presence of carotenoids with 5,6-epoxy-groups (5,6-epoxy- and 5,8-furanoid ß-cryptoxanthin), carotenoids from the α-branch (5,8-furanoid-2'-3'-didehydro α-cryptoxanthin), and 2'-dehydrodeoxomyxol in cyanobacteria. To support the new findings, an in silico search retrieved the putative sequences of carotenogenic enzymes involved in the corresponding biosynthetic pathways (ZEP, NSY, CrtL-b and CrtR) in the analyzed cyanobacteria species. Consequently, high-throughput metabolomics studies assisted by molecular analysis offer a powerful tool for providing insights into the characterization of bioactive compounds and their metabolism in cyanobacteria and microalgae.
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Carotenoides/metabolismo , Cianobactérias/metabolismo , Vias Biossintéticas , Carotenoides/química , Cromatografia Líquida de Alta Pressão , Criptoxantinas/análise , Criptoxantinas/metabolismo , Cianobactérias/química , Metabolômica , Espectrometria de Massas em TandemRESUMO
The objective of this study was to evaluate the effect of carotenoids intake of Scenedesmus obliquus, on lipid peroxidation, the endogenous antioxidant defense system as well as the serum lipid profile in vivo. Male mice were divided into control groups and supplemented with different doses of microalgae carotenoids: 0.25 (MC1) and 2.5 (MC2) mg·kg-1 bodyweight. The lipid profile (total cholesterol, triglycerides, low and high-density lipoprotein) and markers of hepatic toxicity were determined in serum samples. Antioxidant enzymes and thiobarbituric acid reactive substances were determined in the heart, liver, kidneys, and spleen. Both doses used to treat the animals did not show adverse effects by markers of hepatic toxicity. MC1 did not cause significant changes in the serum lipid profile. In contrast, it created a significant reduction in lipid peroxidation of the spleen (46%) as well as an increase in the GR in the heart (40%) and GPx in the kidneys (79%) activity. The MC2 treatment also increased GR (49%) in the heart and GPx (243%) in the heart and kidneys (58%) activity, however, significantly increased levels of lipid peroxidation in the liver (160%) as well as serum triglycerides (60%). According to results, it is suggested that the consumption of S. obliquus carotenoids at the MC1 dose was safe to the animals and could be explored as an alternative to improve the activity of antioxidant enzymes and reduce lipid peroxidation.
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Antioxidantes/metabolismo , Carotenoides/farmacologia , Colesterol/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Microalgas/metabolismo , Animais , Biomarcadores/sangue , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos AnimaisRESUMO
Different cultivation strategies have been developed with the aim of increasing the production rate of microalgal pigments. Specifically, biotechnological approaches are designed to increase antioxidant metabolites as chlorophyll and carotenoids. However, although significant advances have been built up, available information regarding both the chlorophyll metabolism and their oxidative reactions in photobioreactors is scarce. To unravel such processes, the detailed chlorophyll and carotenoid fraction of Scenedesmus obliquus has been studied by HPLC-ESI/APCI-hrTOF-MS from phototrophic and heterotrophic cultures. Scenedesmus is provided with a controlled strategy of interconversion between chlorophyll a and b to avoid the formation of reactive oxygen species (ROS) at high irradiances in addition to the photoacclimation of carotenoids. Indeed, precise kinetics of 132-hydroxy- and 151-hydroxy-lactone chlorophyll metabolites shows the existence of a chlorophyll oxidative metabolism as a tool to manage the excess of energy at high light conditions. Unexpectedly, the oxidation under phototrophy favored chlorophyll b metabolites over the chlorophyll a series, while the heterotrophic conditions exclusively induced the formation of 132-hydroxy-chlorophyll a. In parallel, during the first 48 h of growth in the dark, the chlorophyll fraction maintained a promising steady state. Although future studies are required to resolve the biochemical reactions implied in the chlorophyll oxidative metabolism, the present results agree with phytoplankton metabolism.
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Pre-chilling leads to a temperature decline of the pre-rigor muscle of poultry carcasses, and a reduction of the initial bacterial load may occur. Both ultrasound (US) and slightly acidic electrolyzed water (SAEW) have been used alone in the meat industry for the manufacture of emulsions, pasteurization, and prevention of bacteria growth. However, the impact of the combination of these technologies during the pre-chilling of chicken carcasses has not been evaluated. In this study, breast chicken cylinders (CBCs) were pre-chilled for 10â¯min at 10⯰C using SAEW and different US frequencies (25 and 130â¯kHz). The microbiological characteristics, lipid and protein oxidation, shear force, and anaerobic glycolysis were evaluated. The USâ¯+â¯SAEW combination led to an effective reduction (Pâ¯<â¯0.05) of enterobacteria, mesophilic bacteria, lactic acid bacteria, and psychrotrophic bacteria, while the lipid and protein oxidation, shear force, anaerobic glycolysis, and muscle structure were not affected (Pâ¯>â¯0.05). Therefore, the combination of these technologies may be promising in the pre-chilling stage of chicken carcasses.
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Ácidos/farmacologia , Carga Bacteriana/efeitos dos fármacos , Microbiologia de Alimentos/métodos , Carne/microbiologia , Ultrassom/normas , Animais , Galinhas/microbiologia , Temperatura Baixa , Eletrólise , Água/químicaRESUMO
Sterol profiles were obtained from cyanobacteria Phormidium autumnale, cultivated in a heterotrophic system using three distinct sources of carbon: glucose, sucrose, and agroindustrial slaughterhouse wastewater. A simultaneous saponification-extraction ultrasound-assisted method was performed to determine sterol and other non-saponified compounds in the dry biomasses. A total of 24 compounds were observed in the biomasses, including hope-22,29-en-3-one, squalene, and 22 other sterols. Using wastewater as a carbon source, the microalgae biomass produced a diversity of sterols such as stigmasterol (455.3⯵gâ¯g-1) and ß-sitosterol (279.0⯵gâ¯g-1). However, with glucose it is possible to produce ergosterol (1033.3⯵gâ¯g-1). Squalene was found in all the cultures, with 1440.4⯵gâ¯g-1, 225.4⯵gâ¯g-1, and 425.6⯵gâ¯g-1 for glucose, sucrose, and slaughterhouse wastewater biomasses, respectively. Several intermediate compounds from those sterols were found. These data provide the construction of the sterol metabolism according to the literature for P. autumnale heterotrophically cultured.
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Biomassa , Cianobactérias/metabolismo , Lipidômica/métodos , Esteróis/análise , Esteróis/biossíntese , Carbono/metabolismo , Meios de Cultura/química , Cianobactérias/crescimento & desenvolvimento , Ergosterol/biossíntese , Redes e Vias Metabólicas , Microalgas/metabolismo , Phormidium , Sitosteroides/análise , Esqualeno/análise , Esteróis/isolamento & purificação , Estigmasterol/análise , Águas Residuárias/microbiologiaRESUMO
Environmental factors directly affect the growth and composition of microalgal biomass. Therefore, the present work analyzed the metabolomics (amino acids, organic acids, and fatty acids) of the microalga Scenedesmus obliquus cultivated in 24:0 and 12:12 (light:dark) photoperiods and different phases of cell growth. Furthermore, the metabolites were related to protein, lipid, and chlorophyll contents at the end of cultivation. The highest biomass concentration (4020 mg L- 1) and protein (47.3%) were obtained in culture under constant illumination. The cultivation 12:12 (light:dark) photoperiod triggered higher production of lipids (23.0%) and chlorophylls (26.4 mg g- 1) by S. obliquus. Microalgal metabolites were greatly affected by photoperiod and by phase of cell growth. Thus, metabolite production could be related to both the environmental conditions under which cultivation occurred and to the different concentrations of products (proteins, lipids, and chlorophylls) present in the S. obliquus biomass.
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Biomassa , Clorofila/biossíntese , Ácidos Graxos/biossíntese , Microalgas/crescimento & desenvolvimento , Fotoperíodo , Scenedesmus/crescimento & desenvolvimento , MetabolômicaRESUMO
The initial objective of the study was to evaluate different operation modes (sweep and normal) and frequencies (25 and 130â¯kHz) of ultrasound in pre-chilling of breast chicken cylinders (BCC) immersed in water at 10⯰C during 10â¯min. The second objective was to study the effect of the immersion time (5, 10, 15, 20, and 30â¯min) using the best operation mode and frequency obtained in the pre-chilling of the BCC in water at 10⯰C. Pre-chilling was evaluated in both stages by infrared thermography, and the percentages of water absorption were determined in the second stage. The application of US at 130â¯kHz and normal operation mode provided a reduction of temperature on the surface of BBC higher (≈19.6%) than untreated samples. Also, compared to control, the US-treated samples in these conditions presented a more uniform cooling rate (≈22.3%) and higher water absorption (≈113%).
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Galinhas , Temperatura Baixa , Armazenamento de Alimentos/métodos , Carne/análise , Sonicação/métodos , Absorção Fisico-Química , Animais , Carne/efeitos da radiação , Termografia , Água/químicaRESUMO
A method to simultaneously extract polar (PC) and non-polar compounds (NPC) from microalgae was developed for further determination of intracellular metabolites by gas chromatography. The proposed method was validated and used to characterize two Chlorophyceae, Chlorella vulgaris and Scenedesmus obliquus, and two Cyanobacteria, Aphanothece microscopica Nagëli and Phormidium autumnale. The compounds were extracted with a reduced amount of organic solvent mixture (methanol-chloroform), compared to the reference method, under different conditions of homogenization and/or cell disruption. The NPC were derivatized by acid catalysis, whereas the PC fraction was derivatized using N-methyl,N-tert-Butyldimethylsilyltrifluoroacetamide (MTBSTFA) in alkaline medium. The following parameters for method validation were considered: selectivity, linearity, limit of detection (LOD), limit of quantitation (LOQ), precision, and accuracy. All methods of homogenization and cell disruption extracted both PC and NPC from Chlorophyceae and Cyanobacteria. Derivatization of PC presented satisfactory validation parameters. Eleven fatty acids, six free amino acids, and three organic acids were found within the evaluated microalgae species, succinic, malic, and citric acids, important intermediates of the tricarboxylic acid cycle. Glutamic acid was the amino acid found in greatest quantities in all species. Chlorophyceae presented a higher concentration of unsaturated fatty acids, while Cyanobacteria had more saturated fatty acids. Thus, the proposed method was suitable to metabolically characterize both PC and NPC from microalgae.
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Ácidos Acíclicos/isolamento & purificação , Aminoácidos/isolamento & purificação , Clorofíceas/metabolismo , Cromatografia Gasosa/métodos , Cianobactérias/metabolismo , Ácidos Graxos/isolamento & purificação , Microalgas/metabolismo , Calibragem , Clorofíceas/classificação , Cromatografia Gasosa/normas , Cianobactérias/classificação , Limite de Detecção , Microalgas/classificação , Padrões de Referência , Reprodutibilidade dos Testes , Solventes/químicaRESUMO
ABSTRACT: The aim of this research was to evaluate the enhanced single-cell oil production by cold shock in Aphanothece microscopica Nägeli using dairy processing wastewater as culture medium. The study focused on (i) temperature optimization for biomass production, (ii) cold shock application to induce lipids biosynthesis and (iii) determination of fatty acids profile under different conditions. Results indicated that temperature of 20°C was the best condition in terms of kinetics parameter, reaching biomass productivities of 160.25mg/L.h. Under these conditions, a lipid content of 12.65% was also observed, resulting in a lipid productivity of 20.27mg/L.h. Additionally, the 0°C cold shock was the most efficient in increasing intracellular lipid content, reaching 28.4% in dry weight. Cold shocks also showed influence on the saturation of fatty acid composition, where the saturated fatty acids decreased, and the monounsaturated and polyunsaturated fatty acids increased by increasing the cold application. Thus, the use of cold shocks indicates to be a key condition for improving the prospects of efficient single-cell oils production.
RESUMO: O objetivo deste trabalho foi avaliar o aumento da produção de óleos unicelulares por Aphanothece microscopica Nägeli utilizando água residuária de processamento de laticínios como meio de cultura. O estudo concentrou-se na (i) otimização da temperatura para produção de biomassa, (ii) aplicação de choque frio para induzir a biossíntese de lipídios e (iii) determinação do perfil de ácidos graxos sob diferentes condições. Os resultados indicam que a temperatura de 20°C foi a melhor condição em termos de parâmetros cinéticos, atingindo produtividades de biomassa de 160,25mg/L.h. Nesta condição também foi observado um teor lipídico de 12,65%, o que resultou em uma produtividade lipídica de 20,27mg/L.h. Além disso, o choque frio de 0°C foi o mais eficiente para aumentar o conteúdo lipídico intracelular, que atingiu 28,4% em peso seco. Os choques frios também mostraram influência na saturação da composição de ácidos graxos, em que os ácidos graxos saturados diminuíram, e os ácidos graxos monoinsaturados e poli-insaturados ampliaram com o aumento da aplicação de frio. Assim, o uso de choques frios indica ser uma condição chave para melhorar as perspectivas de produção eficiente de óleos unicelulares.
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ABSTRACT: The high intensity ultrasound-assisted extraction (HIU) is one of the most simple, quick and efficient techniques for the extraction of phenolic and other antioxidant compounds from plants. This is the first application of HIU for the extraction of these compounds from goldenberry fruit. The HIU and conventional extraction techniques showed similar results regarding to phenolic compounds and antioxidant capacity. However, the time required for HIU extraction (5min) was 24 times lower than conventional extraction (120min). Phenolic compounds reported were chlorogenic acid, caffeic acid and rutin. In vitro cytotoxicity assays were used for evaluation of extracts and the results showed that in a wide range of concentration, the extract maintains cell viability, thus indicating the possibility to use it as food with safety.
RESUMO: A extração assistida com ultrassom de alta intensidade (HIU) é uma das técnicas mais simples, rápidas e eficientes na extração de compostos fenólicos e antioxidantes de plantas. Este trabalho foi o primeiro a utilizar HIU na extração destes compostos presentes na fruta goldenberry. As técnicas HIU e extração convencional apresentaram resultados semelhantes com relação aos compostos fenólicos e capacidade antioxidante. Entretanto, o tempo necessário na HIU (5min) foi 24 vezes menor que na extração convencional (120min). Os compostos fenólicos encontrados foram ácido clorogênico, ácido cafeico e rutina. Ensaios de citotoxicidade in vitro foram usados para avaliação dos extratos e os resultados demonstraram que, em ampla faixa de concentração, o extrato mantém a viabilidade celular, indicando assim possível segurança para utilização em alimentos.