Supercritical fluid extraction of astaxanthin-rich extracts from Haematococcus pluvialis: Economic assessment.

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.

Methodological Optimization of Supercritical Fluid Extraction of Valuable Bioactive Compounds from the Acidophilic Microalga Coccomyxa onubensis.

Microalgae grow in diverse environments and possess a great biotechnological potential as they contain useful bioactive compounds. These bioactive compounds can be obtained by selective and energy-efficient extraction methods. Various industries are using the supercritical fluid extraction (SFE) method to extract these valuable bioactive compounds. Hence, for the first time, we evaluated the effects of SFE on the recovery of bioactive and antioxidant compounds using Coccomyxa onubensis, a eukaryotic acidophilic microalga of potential relevance which can be used in the field of nutraceutical and functional foods. It was isolated from the Tinto River (Pyritic Belt, Huelva, Spain), a mining region in Spain. Variables such as extraction yield, lutein purity (LP) and recovery (LR), total phenols, and antioxidant capacity (Trolox equivalents antioxidant capacity method) were studied using a Box-Behnken design based on a response surface methodology along with the overall extraction curve fitted to a spline linear model. The effects of temperature (30, 50, and 70 °C), pressure (25, 40, and 55 MPa), and the percentage of co-solvent (0, 25%, and 50% v/v ethanol) on SFE were analyzed, resulting in the co-solvent and temperature as the most significant factors followed by the pressure. Under 70 °C, 40 MPa, and 50% v/v ethanol, C. onubensis reached a maximum of 66.98% of LR. The extracts were richest in total phenols and showed the maximum antioxidant activity (36.08 mg GAEs/g extracts and 2.237 mmol TE/g extracts, respectively) under similar pressure and co-solvent percentage values and different temperatures (30 and 70 °C, respectively). The extracts obtained in this study may have potential applications in the food, nutraceutical, and cosmetic industries. SFE is a highly efficient method to valorize microorganisms living in extreme environments, which are so far unexplored using green extraction methods.

Supercritical Fluid Extraction of Fucoxanthin from the Diatom Phaeodactylum tricornutum and Biogas Production through Anaerobic Digestion.

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.

Effect of CO2 Flow Rate on the Extraction of Astaxanthin and Fatty Acids from Haematococcus pluvialis Using Supercritical Fluid Technology.

Haematococcus pluvialis is the largest producer of natural astaxanthin in the world. Astaxanthin is a bioactive compound used in food, feed, nutraceutics, and cosmetics. In this study, astaxanthin extraction from H. pluvialis by supercritical fluid extraction was evaluated. The effects of temperature (40 and 50 °C), pressure (40 and 50 MPa), and CO2 flow rate (2 and 4 L/min) were investigated. The results showed that the highest astaxanthin recovery was obtained at 50 °C/50 MPa and the CO2 flow rates evaluated had no significant effect. It was possible to achieve astaxanthin recoveries of 95% after 175 min for a CO2 flow rate of 2 L/min, and 95 min for CO2 flow rate of 4 L/min. The ω-6/ω-3 ratios obtained were similar in all conditions, reaching 0.87, demonstrating that the extracts from H. pluvialis by SFE are rich in unsaturated fatty acids (UFA) which increases their positive effects when used as a functional ingredient in food.

Isotonic Beverage Pigmented with Water-Dispersible Emulsion from Astaxanthin Oleoresin.

Astaxanthin is a powerful antioxidant, because it neutralizes free radicals and plays a vital role in the prevention of human diseases. The objective of this work was to develop an isotonic beverage (IB) of orange-red color, using an astaxanthin oleoresin emulsion (AOE) that is dispersible in water. This was carried out in order to simulate the color of commercial isotonic beverages (CIB) prepared from artificial pigments. The size of the AOE micelles ranged from 0.15 to 7.60 µm2. The color difference (ΔE) was similar for the samples exposed to dark as well as light conditions. The samples subjected to light stress showed pigment degradation after seven days, followed by a decrease in the concentration of astaxanthin; whereas, the samples exposed to dark conditions remained stable for seven days and then showed a decrease in the concentration of astaxanthin (this decrease ranged from 65% to 76% when compared to the initial content) after a period of 91 days. For the astaxanthin oleoresin (AO) and AOE, the oxygen radical absorbance capacity (ORAC) values reached 5224 and 1968 µmol of trolox equivalents (TE)/100 g, respectively. When exposed to light conditions, the addition of AOE in the IB led to its rapid degradation, while it remained stable in the samples exposed to the dark conditions.

Suplemento alimenticio de alto contenido proteico para niños de 2-5 años II propiedades físicas, químicas, reológicas y color / Nutritional supplement of high protein content for children 2-5 years old II physical, chemical, rheological and color properties

La elaboración de mezclas de harinas proteicas con destino a la población preescolar de 2-5 años ha sido una práctica común en las últimas décadas. El presente trabajo tuvo como objetivo la evaluación de algunas propiedades físicas, químicas, reológicas y el color de una crema preparada a partir de un suplemento alimenticio formulado a partir de harinas de quinua y lupino con aditivos y saborizante de pollo para un período de conservación de 90 días. Además, se evaluaron algunas propiedades mecánicas y de fluidez del polvo al finalizar el almacenamiento. Los resultados obtenidos fueron: humedad <10,5 por ciento y Aw <0,61 sin variaciones significativas; el índice de peróxido aumentó gradualmente con un comportamiento lineal, alcanzando 8,34meq O2 por kg de grasa. La crema preparada a partir de la mezcla formulada mostró un comportamiento seudoplástico, disminuyendo en el transcurso del tiempo pese a mantener alta consistencia. Las coordenadas de color CIEL*a*b* no presentaron diferencias significativas en todo el período de almacenamiento, manteniéndose el color en una tonalidad de “beige”. El DE mostró comportamientos erráticos hasta 45 días y se estabilizó a los 90 días. La capacidad de retención de agua de la mezcla a los 0 días fue de 2,3 ±0,06 veces. Al final del estudio la densidad aparente y de asentamiento fueron de 0,463 y 0,526 g·ml-1, y el tiempo y velocidad de vaciado de 1,38s y de 13,66g·cm-2·s-1, alcanzando el ángulo de reposo 38,4º, lo que lo ubica como de fluidez lenta.

Suplemento alimenticio de alto contenido proteico para niños de 2 a 5 años: desarrollo de la formulacion y aceptabilidad / Nutritional suplement of high protein content for 2-5 year old children: development of the formulation and acceptability

Las combinaciones de cereales-leguminosas ofrecen proteínas de alta calidad debido a la compensación de sus aminoácidos esenciales. Se seleccionó la quinua (Chenopodium quinua Willd) y el lupino (Lupinus albus L.) con el objetivo de diseñar una formulación de alto contenido proteico con aditivos y saborizante de pollo para lograr una mezcla física en polvo que al adicionarle agua, se obtuviera una crema tipo “papilla” destinada a niños de 2-5 años, con contenido aminoacídico de 35-40% del requerimiento diario, aplicando técnicas de Programación Lineal. En la formulación seleccionada se determinó su composición por análisis proximal y se realizaron algunas pruebas físicas y microbiológicas. Se efectuaron pruebas sensoriales por atributos en adultos semientrenados y se aplicó la escala hedónica facial de 5 puntos a niños preescolares de tres jardines infantiles de Antofagasta, Chile. El contenido proteico de la harina de lupino (49,77g×100g) superó en 4,6 veces a la quinua (10,82g×100g), pero no contuvo todos los aminoácidos esenciales, siendo la complementación de ambas, una proteína de buena calidad. Los resultados microbiológicos del producto fueron satisfactorios. La papilla obtuvo un puntaje entre “me gusta ligeramente” y “me gusta muchísimo”, mostrando buena aceptación por niños de 2-5 años. Además, proporcionó un PDCAAS (protein digestibility corrected amino acid score) de 0,9, a los 90 días de elaborada, pues los aminoácidos esenciales, triptófano y el conjunto, metionina + cistina, no lograron cumplir con el patrón establecido por la FAO.