RESUMEN

OBJECTIVE: To investigate the effect of astaxanthin supplementation in cryopreservation media on post-thawed sperm motility, viability, morphology, reactive oxygen species (ROS), and DNA fragmentation in two cryopreservation techniques using vitrification and liquid nitrogen vapor freezing. METHODS: Thirty normozoospermic semen samples were used in the study. Post-prepared semen samples were divided into 1) non-cryopreserved control, 2) and 3) vitrified without (V) and with astaxanthin 0.5 µM (V+ATX), 4) and 5) frozen in liquid nitrogen vapor without (L) and with astaxanthin 0.5 µM (L+ATX). RESULTS: Cryopreservation using vitrification and liquid nitrogen vapor freezing significantly decreased sperm motility and viability and increased ROS levels. However, no changes were seen in sperm morphology or DNA fragmentation. The addition of astaxanthin in cryopreservation media significantly increased post-thawed motility in both vitrification (77.6±8.9% vs. 69.0±9.5% in V+ATX and V) and vapor freezing (57.0±13.3% vs. 47.7±14.6% in L+ATX and L); it significantly increased sperm viability in vitrification (75.0±11.9% vs. 65.9±11.1% in V+ATX and V), and significantly decreased ROS level in both vitrification (4.7 (2.6-8.3) RLU/sec/106 vs. 10.6 (9.4-16.0) RLU/sec/106 in V+ATX and V) and vapor freezing (4.6 (3.3-10.5) RLU/sec/106 vs. 10.3 (7.9-18.6) RLU/ sec/106 in L+ATX and L). Astaxanthin supplementation in cryopreservation media did not affect sperm morphology or DNA fragmentation. CONCLUSIONS: Astaxanthin supplementation improved post-cryopreserved sperm motility, decreased ROS levels in both vitrification and liquid nitrogen vapor freezing and improved sperm viability only in the vitrification technique.

RESUMEN

The consumption of fatty acids offers significant health benefits; however, they are prone to degradation by environmental factors. One method to preserve these fatty acids is the addition of synthetic antioxidants. This study focuses on the determination of peroxide and MDA formation rates at temperatures of 25 °C, 45 °C, and 65 °C. The oxidative stability of cold-pressed avocado oil was evaluated using pure astaxanthin, TBHQ, and H. pluvialis extract at concentrations of 100, 500, and 1000 ppm. Kinetic models and thermodynamic analysis were applied to determine the oxidation rate and compare the antioxidant effects of H. pluvialis extract with astaxanthin and TBHQ. The Arrhenius model was used to estimate activation energy (Ea), enthalpy, entropy, and free energy. Avocado oil with 500 ppm of H. pluvialis extract showed antioxidant effects comparable to TBHQ and pure astaxanthin. The activation energy of plain avocado oil was 40.47 kJ mol-1, while with H. pluvialis extract, it was 54.35 kJ mol-1. These findings suggest that H. pluvialis extract offers effective antioxidant properties and could serve as a natural alternative to synthetic antioxidants in food applications, despite the limitations of unprotected astaxanthin.

RESUMEN

Metabolic Syndrome (MS) is a cluster of metabolic risk factors, characterized by abdominal obesity, dyslipidemia, hypertension, insulin resistance, among others. The purpose of the study was to evaluate the astaxanthin (AXT) effects extracted from freshwater crab (Dilocarcinus pagei) at the Paraná Basin on lipotoxicity, lipid peroxidation and oxidative stress in the kidney of rats fed with a sucrose-rich diet (SRD). We hypothesized that daily administration of AXT prevents kidney damage by reducing lipotoxicity, lipid peroxidation, and reactive oxygen species (ROS), and by improving antioxidant enzyme defenses and crosstalk between NrF2 and NF-ĸB transcription factors. Male Wistar rats were fed a reference diet (RD), RD+AXT, SRD and SRD+AXT (AXT daily oral dose: [10 mg/kg body weight]) for 90 days. Systolic and diastolic blood pressure, biochemical assays in serum and urine were evaluated. Renal cortex samples were taken for histological analysis, determination of triglyceride content, ROS, thiobarbituric acid reactive substances (TBARS), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) enzyme activities and glutathione content (GSH). 4-HNE, NrF2, and NF-ĸB p65 expression were analyzed by immunohistochemistry. We demonstrated that daily oral supplementation of AXT to animals fed a SRD reduced systolic and diastolic blood pressure, histological renal damage, lipid accumulation, ROS and lipid peroxidation, and increased CAT and GPx activities. NrF2 protein expression in renal cortex was increased, whilst NF-ĸB p65 was reduced. AXT extracted from freshwater crabs (Dilocarcinus pagei) may be promising nutritional strategy for the prevention of renal alterations present in this model.

RESUMEN

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

RESUMEN

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.

Asunto(s)

Basidiomycota , Técnicas de Cultivo Celular por Lotes , Carotenoides , Carbono , Glucósidos , Nitrógeno , Xantófilas

RESUMEN

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.

Asunto(s)

Antineoplásicos , Melanoma Experimental , Ratones , Animales , Línea Celular Tumoral , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Apoptosis , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Autofagia , Proliferación Celular , Ratones Endogámicos C57BL , Xantófilas

RESUMEN

INTRODUCTION: osteoarthritis is one of the most prevalent chronic diseases in the world and is defined as the gradual loss of cartilage in the joints, mainly that of the knee. It is considered a cause of disability in older adults and is characterized by pain, stiffness and loss of mobility. MATERIAL AND METHODS: observational study to evaluate the effect of the combination of non-hydrolyzed type II native collagen (CII-NH), omega-3 (Om-3) and astaxanthin (AX), in a population of 182 patients with knee osteoarthritis grade I/II. Measurements of thigh circumference, arcs of movement and pain were obtained through international scales such as the visual analogue pain scale (VAS), the Lequesne index and the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) scale. Medical check-ups were performed every 30 days for three months. The Statgraphics software (Statgraphics Technologies, Virginia) was used, the evaluation of the variables and the statistical significance were determined by t Student test and the results are shown as a mean. RESULTS: it was shown that daily consumption increases mobility, decreases knee pain and inflammation in patients within three months. Additionally, there was a reduction in the consumption of nonsteroidal anti-inflammatory drugs (NSAIDs) by the study subjects. CONCLUSION: the fixed combination of non-hydrolyzed type II collagen, omega-3 and astaxanthin, generates, in the short term, a decrease in inflammation and stiffness in patients with osteoarthritis.

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INTRODUCCIÓN: la osteoartritis es una de las enfermedades crónicas con mayor prevalencia en el mundo y se define como la pérdida gradual de cartílago en las articulaciones, principalmente la de rodilla. Es considerada como una causa de discapacidad en adultos mayores y se caracteriza por dolor, rigidez y pérdida de la movilidad. MATERIAL Y MÉTODOS: estudio observacional para evaluar el efecto de la combinación de Sólo debe decir, colágeno nativo tipo II, omega-3 (Om-3) y astaxantina (AX), en una población de 182 pacientes con artrosis de rodilla grado I/II. Se obtuvieron las mediciones de circunferencia del muslo, arcos de movimiento y dolor a través de las escalas internacionales como la escala visual analógica de dolor (EVA), el índice de Lequesne y escala Western Ontario McMaster Universities Osteoarthritis Index (WOMAC). Las revisiones médicas se realizaron cada 30 días durante tres meses. Se utilizó el software Statgraphics (Statgraphics Technologies, Virginia), la evaluación de las variables y la significancia estadística fueron determinadas por la prueba t de Student y los resultados se muestran como media. RESULTADOS: se demostró que el consumo diario incrementa la movilidad, disminuye el dolor y la inflamación de rodilla en los pacientes en un lapso de tres meses. Adicionalmente se registró una reducción en el consumo de antiinflamatorios no esteroideos (AINE) por parte de los sujetos de estudio. CONCLUSIÓN: la combinación fija colágeno nativo tipo II, omega-3 y astaxantina, genera, en el corto plazo, disminución de la inflamación y la rigidez en pacientes con osteoartritis.

Asunto(s)

Osteoartritis de la Rodilla , Humanos , Anciano , Osteoartritis de la Rodilla/tratamiento farmacológico , Colágeno Tipo II , Resultado del Tratamiento , Dolor , Inflamación

RESUMEN

Dilocarcinus pagei is a South American crab commonly found in fishponds. As crabs are a source of astaxanthin (AST) and food inputs, this preliminary research aimed at studying the composition of females and males of this species to assess its potential for commercial applications, and at optimising the extraction of AST with edible oils to promote its use as an ingredient for the nutraceutical, pharmaceutical and feed industries. The chemical composition differed between males and females only in moisture, and the values obtained were: 65.4 ± 1.0% and 72.5 ± 3.1% moisture, 45.7-40.3% d.m. minerals, 22.0-24.1% d.m. fibres, 18.2-17.4% d.m. proteins, and 10.4-11.1% d.m. lipids. The Box-Behnken design was applied and validated for extraction with soya bean and sunflower oils, adjusting the oil:crab ratio, temperature, and extraction time. The optimal conditions found consisted of 140 mL/g, 90 °C and 170 min for soya bean oil, reaching an accumulation of AST of 50 ± 5 µg/g crab d.m. For sunflower oil, the conditions were 60 mL/g, 90 °C and 161 min, reaching 31 ± 3 µg/g crab d.m. Finally, the amounts of AST obtained using soya bean oil were higher than those obtained using sunflower oil; thus, soya bean oil would be recommended as a solvent to extract the pigment.

RESUMEN

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.

Asunto(s)

Antioxidantes , Ingeniería Genética , Xantófilas , Levaduras

RESUMEN

Colouring has a great influence on the commercialization of ornamental fish. The aim of this study was to evaluate different concentrations of canthaxanthin in the diet of the blood swordtail Xiphophorus helleri in an effort to obtain a more intense red colour. Six concentrations of canthaxanthin (0, 50, 100, 250, 400 and 600 mg kg-1 diet) were used. The experiment lasted 60 days. Fish were evaluated for increased red pigmentation through the use of photographs (performed by smartphone) and imaging applications considering the Hunter method and the CMYK and productive performance. No significant differences were observed for productive performance. The use of photographs by means of a smartphone and the use of imaging applications proved to be adequate to assess differences in colour in the species. Swordtail red pigmentation did not show significant increase regardless of canthaxanthin dosages. Varieties of ornamental fish bred for red coloration may have limits for increased colour due to the storage capacity of carotenoids by chromatophores.

Asunto(s)

Cantaxantina , Ciprinodontiformes , Animales , Color , Carotenoides , Dieta/veterinaria

RESUMEN

Resumen: Introducción: la osteoartritis es una de las enfermedades crónicas con mayor prevalencia en el mundo y se define como la pérdida gradual de cartílago en las articulaciones, principalmente la de rodilla. Es considerada como una causa de discapacidad en adultos mayores y se caracteriza por dolor, rigidez y pérdida de la movilidad. Material y métodos: estudio observacional para evaluar el efecto de la combinación de Sólo debe decir, colágeno nativo tipo II, omega-3 (Om-3) y astaxantina (AX), en una población de 182 pacientes con artrosis de rodilla grado I/II. Se obtuvieron las mediciones de circunferencia del muslo, arcos de movimiento y dolor a través de las escalas internacionales como la escala visual analógica de dolor (EVA), el índice de Lequesne y escala Western Ontario McMaster Universities Osteoarthritis Index (WOMAC). Las revisiones médicas se realizaron cada 30 días durante tres meses. Se utilizó el software Statgraphics (Statgraphics Technologies, Virginia), la evaluación de las variables y la significancia estadística fueron determinadas por la prueba t de Student y los resultados se muestran como media. Resultados: se demostró que el consumo diario incrementa la movilidad, disminuye el dolor y la inflamación de rodilla en los pacientes en un lapso de tres meses. Adicionalmente se registró una reducción en el consumo de antiinflamatorios no esteroideos (AINE) por parte de los sujetos de estudio. Conclusión: la combinación fija colágeno nativo tipo II, omega-3 y astaxantina, genera, en el corto plazo, disminución de la inflamación y la rigidez en pacientes con osteoartritis.

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Abstract: Introduction: osteoarthritis is one of the most prevalent chronic diseases in the world and is defined as the gradual loss of cartilage in the joints, mainly that of the knee. It is considered a cause of disability in older adults and is characterized by pain, stiffness and loss of mobility. Material and methods: observational study to evaluate the effect of the combination of non-hydrolyzed type II native collagen (CII-NH), omega-3 (Om-3) and astaxanthin (AX), in a population of 182 patients with knee osteoarthritis grade I/II. Measurements of thigh circumference, arcs of movement and pain were obtained through international scales such as the visual analogue pain scale (VAS), the Lequesne index and the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) scale. Medical check-ups were performed every 30 days for three months. The Statgraphics software (Statgraphics Technologies, Virginia) was used, the evaluation of the variables and the statistical significance were determined by t Student test and the results are shown as a mean. Results: it was shown that daily consumption increases mobility, decreases knee pain and inflammation in patients within three months. Additionally, there was a reduction in the consumption of nonsteroidal anti-inflammatory drugs (NSAIDs) by the study subjects. Conclusion: the fixed combination of non-hydrolyzed type II collagen, omega-3 and astaxanthin, generates, in the short term, a decrease in inflammation and stiffness in patients with osteoarthritis.

RESUMEN

BACKGROUND: Traditional production of dry salted shrimp enhances cholesterol oxidation and astaxanthin degradation in the product. The aim of this study was to evaluate the effect of addition of the antioxidants butylhydroxytoluene (BHT) and tert-butylhydroquinone (TBHQ) to cooked shrimp on the formation of cholesterol oxidation products (COPs) and astaxanthin degradation during solar drying of shrimp. RESULTS: The added antioxidants significantly inhibited COPs formation after the product was boiled in brine. Smaller amounts of COPs were formed in antioxidant-treated shrimps (~-23%) as compared to untreated samples. The antioxidants continued to significantly inhibit COPs formation (~-39%) during sun drying. Similarly, TBHQ and BHT reduced by 51.3% and 37.2%, respectively, the degradation rate of astaxanthin, favoring a higher retention of this carotenoid in the final product. CONCLUSION: The use of the antioxidants BHT and TBHQ in the preparation of dry salted shrimp significantly inhibited the formation of COPs after cooking raw shrimp and during direct solar drying. They also protected astaxanthin contained in the cooked shrimp from photodegradation. These results are technologically relevant because it is possible to prepare a product with a higher content of astaxanthin and lower the presence of hazardous COPs. © 2022 Society of Chemical Industry.

Asunto(s)

Antioxidantes , Hidroquinonas , Antioxidantes/farmacología , Antioxidantes/química , Colesterol

RESUMEN

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.

Asunto(s)

Basidiomycota , Saccharomyces cerevisiae , Humanos , Xantófilas , Biotecnología , Basidiomycota/química

RESUMEN

Microorganisms such as bacteria, microalgae and fungi, are natural and rich sources of several valuable bioactive antioxidant's compounds, including carotenoids. Among the carotenoids with antioxidant properties, astaxanthin can be highlighted due to its pharmaceutical, feed, food, cosmetic and biotechnological applications. The best-known producers of astaxanthin are yeast and microalgae cells that biosynthesize this pigment intracellularly, requiring efficient and sustainable downstream procedures for its recovery. Conventional multi-step procedures usually involve the consumption of large amounts of volatile organic compounds (VOCs), which are regarded as toxic and hazardous chemicals. Considering these environmental issues, this review is focused on revealing the potential of unconventional extraction procedures [viz., Supercritical Fluid Extraction (SFE), Ultrasound-Assisted Extraction (UAE), Microwave-Assisted Extraction (MAE), High-Pressure Homogenization (HPH)] combined with alternative green solvents (biosolvents, eutectic solvents and ionic liquids) for the recovery of microbial-based astaxanthin from microalgae (such as Haematococcus pluvialis) and yeast (such as Phaffia rhodozyma) cells. The principal advances in the area, process bottlenecks, solvent selection and strategies to improve the recovery of microbial astaxanthin are emphasized. The promising recovery yields using these environmentally friendly procedures in lab-scale are good indications and directions for their effective use in biotechnological processes for the production of commercial feed and food ingredients like astaxanthin.

Asunto(s)

Antioxidantes , Microalgas , Biomasa , Saccharomyces cerevisiae , Carotenoides , Solventes/química

RESUMEN

Abstract Objectives: 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.

RESUMEN

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.

Asunto(s)

Chlorophyceae , Cromatografía con Fluido Supercrítico , Cromatografía con Fluido Supercrítico/métodos , Solventes , Xantófilas

RESUMEN

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.

Asunto(s)

Chlorophyceae , Microalgas , Biomasa , Floculación , Agua , Xantófilas

RESUMEN

In patients with age-related macular degeneration (AMD), the crucial retinal pigment epithelial (RPE) cells are characterized by mitochondria that are structurally and functionally defective. Moreover, deficient expression of the mRNA-editing enzyme Dicer is noted specifically in these cells. This Dicer deficit up-regulates expression of Alu RNA, which in turn damages mitochondria-inducing the loss of membrane potential, boosting oxidant generation, and causing mitochondrial DNA to translocate to the cytoplasmic region. The cytoplasmic mtDNA, in conjunction with induced oxidative stress, triggers a non-canonical pathway of NLRP3 inflammasome activation, leading to the production of interleukin-18 that acts in an autocrine manner to induce apoptotic death of RPE cells, thereby driving progression of dry AMD. It is proposed that measures which jointly up-regulate mitophagy and mitochondrial biogenesis (MB), by replacing damaged mitochondria with "healthy" new ones, may lessen the adverse impact of Alu RNA on RPE cells, enabling the prevention or control of dry AMD. An analysis of the molecular biology underlying mitophagy/MB and inflammasome activation suggests that nutraceuticals or drugs that can activate Sirt1, AMPK, Nrf2, and PPARα may be useful in this regard. These include ferulic acid, melatonin urolithin A and glucosamine (Sirt1), metformin and berberine (AMPK), lipoic acid and broccoli sprout extract (Nrf2), and fibrate drugs and astaxanthin (PPARα). Hence, nutraceutical regimens providing physiologically meaningful doses of several or all of the: ferulic acid, melatonin, glucosamine, berberine, lipoic acid, and astaxanthin, may have potential for control of dry AMD.

Asunto(s)

Berberina , Degeneración Macular , Melatonina , Ácido Tióctico , Proteínas Quinasas Activadas por AMP/metabolismo , Berberina/farmacología , ADN Mitocondrial/metabolismo , Suplementos Dietéticos , Glucosamina , Humanos , Inflamasomas/metabolismo , Degeneración Macular/tratamiento farmacológico , Melatonina/metabolismo , Mitocondrias/metabolismo , Mitofagia , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Biogénesis de Organelos , Estrés Oxidativo , PPAR alfa/metabolismo , ARN/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Sirtuina 1/metabolismo

RESUMEN

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.

Asunto(s)

Diabetes Mellitus Experimental , Pérdida Auditiva , Xantófilas , Animales , Ratas , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Citocinas , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/tratamiento farmacológico , Glutatión Peroxidasa/metabolismo , Pérdida Auditiva/tratamiento farmacológico , Pérdida Auditiva/etiología , Pérdida Auditiva/prevención & control , Superóxido Dismutasa , Xantófilas/uso terapéutico

RESUMEN

Cytochrome P450s (P450s) are heme-containing proteins involved in several cellular functions, including biosynthesis of steroidal hormones, detoxification of xenobiotic compounds, among others. Damage response protein 1 (Dap1) has been described as a positive regulator of P450s through protein-protein interactions in organisms such as Schizosaccharomyces pombe. Three P450s in the carotenogenic yeast Xanthophyllomyces dendrorhous have thus far been characterized: Cyp51 and Cyp61, which are involved in ergosterol biosynthesis, and CrtS (astaxanthin synthase), which is involved in biosynthesis of the carotenoid astaxanthin. In this work, we describe the X. dendrorhous DAP1 gene, deletion of which affected yeast pigmentation by decreasing the astaxanthin fraction and increasing the ß-carotene (a substrate of CrtS) fraction, which is consistent with the known role of CrtS. We found that the proportion of ergosterol was also decreased in the Δdap1 mutant. However, even though the fractions of the end products of these two pathways (the synthesis of carotenoids and sterols) were decreased in the Δdap1 mutant, the transcript levels of genes from the P450 systems involved were higher than those in the wild-type strain. We demonstrate that Dap1 coimmunoprecipitates with these three P450s, suggesting that Dap1 interacts with these three proteins. We propose that Dap1 regulates the synthesis of astaxanthin and ergosterol in X. dendrorhous, probably by regulating the P450s involved in both biosynthetic pathways at the protein level. This work suggests a new role for Dap1 in the regulation of carotenoid biosynthesis in X. dendrorhous.

Asunto(s)

Carotenoides , Fitosteroles , Basidiomycota , Carotenoides/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Ergosterol , Esteroles