A HPLC‐DAD method for identifying and estimating the content of fucoxanthin, β‐carotene and chlorophyll a in brown algal extracts

Seaweeds are photosynthetic organisms that have high contents of pigments. The coloration of each alga is defined by the content and combination of pigments synthesized, which varies among species and environmental conditions. The most abundant pigments in algae are chlorophylls and carotenoids, lipophilic molecules that can be used as natural colorants and have high acceptance by consumers. In this work, a simple and short hands-on time HPLC-DAD method for identifying and estimating the pigment content of algal extracts, specifically fucoxanthin, ��-carotene and chlorophyll a was carried out. Using this optimized method, a pigment screening was performed on the ethanolic extracts obtained by ultrasound-assisted extraction from nine brown algal from the Atlantic coastline: Ascophyllum nodosum, Bifurcaria bifurcata, Fucus spiralis, Himanthalia elongata, Laminaria saccharina, Laminaria ochroleuca, Pelvetia canaliculata, Sargassum muticum and Undaria pinnatifida. HPLC results permitted to highlight L. saccharina and U. pinnatifida as promising sources of these three target pigments containing a total amount of 10.5 – 11.5 mg per gram of dry weight. Among them, the most abundant one was fucoxanthin, an added-value compound with a high potential to be commercially exploited by different industries, such as the food, cosmetic, and pharmaceutical sectors.Ministerio de Ciencia e Innovación | Ref. RYC-2017-22891Ministerio de Ciencia e Innovación | Ref. FPU2016/06135Xunta de Galicia | Ref. ED481B-2019/096CYTED—AQUA-CIBUS | Ref. P317RT0003European Commission | Ref. ERA-NET ERA-HDHL n. 696295Fundação para a Ciência e a Tecnologia | Ref. PTDC/OCE-ETA/30240/201

Benefits and drawbacks of ultrasound-assisted extraction for the recovery of bioactive compounds from marine algae

The increase in life expectancy has led to the appearance of chronic diseases and interest in healthy aging, in turn promoting a growing interest in bioactive compounds (BCs) and functional ingredients. There are certain foods or products rich in functional ingredients, and algae are one of them. Algae consumption has been nominal in Europe until now. However, in recent years, it has grown significantly, partly due to globalization and the adoption of new food trends. With the aim of obtaining BCs from foods, multiple methods have been proposed, ranging from conventional ones, such as maceration or Soxhlet extraction, to more innovative methods, e.g., ultrasound-assisted extraction (UAE). UAE constitutes a novel method, belonging to so-called green chemistry, that enables the extraction of BCs requiring lower amounts of solvent and energy costs, preserving the integrity of such molecules. In recent years, this method has been often used for the extraction of different BCs from a wide range of algae, especially polysaccharides, such as carrageenans and alginate; pigments, including fucoxanthin, chlorophylls, or -carotene; and phenolic compounds, among others. In this way, the application of UAE to marine algae is an efficient and sustainable strategy to pursue their deep characterization as a new source of BCs, especially suitable for vegetarian and vegan diets.The research leading to these results was supported by MICINN supporting the Ramón y Cajal grant for M.A. Prieto (RYC-2017-22891) and the FPU grant for A. Carreira-Casais (FPU2016/06135); by Xunta de Galicia for supporting the pre-doctoral grants of P. Garcia-Oliveira (ED481A-2019/295) and A.G. Pereira (ED481A-2019/0228); by University of Vigo for supporting the predoctoral grant of M. Carpena (Uvigo-00VI 131H 6410211) and by Becas de Fundación ONCE Programme “Oportunidad al Talento” that supports the work of A. Soria-Lopez.info:eu-repo/semantics/publishedVersio

Xanthophylls from the sea: Algae as source of bioactive carotenoids

Algae are considered pigment-producing organisms. The function of these compounds in algae is to carry out photosynthesis. They have a great variety of pigments, which can be classified into three large groups: chlorophylls, carotenoids, and phycobilins. Within the carotenoids are xanthophylls. Xanthophylls (fucoxanthin, astaxanthin, lutein, zeaxanthin, and β-cryptoxanthin) are a type of carotenoids with anti-tumor and anti-inflammatory activities, due to their chemical structure rich in double bonds that provides them with antioxidant properties. In this context, xanthophylls can protect other molecules from oxidative stress by turning off singlet oxygen damage through various mechanisms. Based on clinical studies, this review shows the available information concerning the bioactivity and biological effects of the main xanthophylls present in algae. In addition, the algae with the highest production rate of the different compounds of interest were studied. It was observed that fucoxanthin is obtained mainly from the brown seaweeds Laminaria japonica, Undaria pinnatifida, Hizikia fusiformis, Sargassum spp., and Fucus spp. The main sources of astaxanthin are the microalgae Haematococcus pluvialis, Chlorella zofingiensis, and Chlorococcum sp. Lutein and zeaxanthin are mainly found in algal species such as Scenedesmus spp., Chlorella spp., Rhodophyta spp., or Spirulina spp. However, the extraction and purification processes of xanthophylls from algae need to be standardized to facilitate their commercialization. Finally, we assessed factors that determine the bioavailability and bioaccesibility of these molecules. We also suggested techniques that increase xanthophyll's bioavailability.The research leading to these results was funded by Xunta de Galicia supporting the Axudas Conecta Peme, the IN852A 2018/58 NeuroFood Project and the program EXCELENCIAED431F 2020/12; to Ibero-American Program on Science and Technology (CYTED—AQUA-CIBUS, P317RT0003) and to the Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBI-JTI-2019). The JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The project SYSTEMIC Knowledge hub on Nutrition and Food Security, has received funding from national research funding parties in Belgium (FWO), France (INRA), Germany (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint action of JPI HDHL, JPI-OCEANS and FACCE-JPI launched in 2019 under the ERA-NET ERA-HDHL (nº 696295).info:eu-repo/semantics/publishedVersio

Emerging technologies to extract fucoxanthin from Undaria pinnatifida: microwave vs. ultrasound assisted extractions

Macroalgae are an extensive resource for the obtention of bioactive compounds, mainly phenolic compounds, phlorotannins, and pigments. Fucoxanthin (Fx) is the most abundant pigment present in brown algae and has shown several useful bioactivities that can be used to fortify products in the food and cosmetic industries. Nevertheless, to date, there is still insufficient literature reporting on the extraction yield of Fx from U. pinnatifida species from green technologies. In this regard, the present study aims to optimize the extraction conditions to obtain the highest Fx yield from U. pinnatifida through emerging techniques, namely microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE). These methods will be compared with the conventional methodologies of heat-assisted extraction (HAE) and Soxhlet-assisted extraction (SAE). According to our results, even though the extraction yield could be slightly higher when using MAE than UAE, the Fx concentration obtained from the alga was double when using UAE. Thus, the Fx ratio in the final extract reached values of 124.39 mg Fx/g E. However, the optimal conditions should also be considered since UAE needed 30 min to perform the extraction, whereas MAE was able to obtain 58.83 mg Fx/g E in only 3 min and 2 bar, meaning less energy expenditure and minimum cost function. To our knowledge, this study obtains the highest concentrations of Fx ever reported (58.83 mg Fx/g E for MAE and 124.39 mg Fx/g E for UAE), with low energy consumption and short times (3.00 min for MAE and 35.16 min for UAE). Any of these results could be selected for further experiments and proposed for industrial scaling-up.Ministerio de Ciencia e Innovación | Ref. RYC-2017-22891Ministerio de Ciencia e Innovación | Ref. FPU2016/06135Xunta de Galicia | Ref. ED431F 2020/12Xunta de Galicia | Ref. ED481A 2021/31

Evolution of flavors in extra virgin olive oil shelf-life

Extra virgin olive oil (EVOO) is one of the most distinctive ingredients of the Mediterranean diet. There are many properties related to this golden ingredient, from supreme organoleptic characteristics to benefits for human health. EVOO contains in its composition molecules capable of exerting bioactivities such as cardio protection, antioxidant, anti-inflammatory, antidiabetic, and anticancer activity, among others, mainly caused by unsaturated fatty acids and certain minor compounds such as tocopherols or phenolic compounds. EVOO is considered the highest quality vegetable oil, which also implies a high sensory quality. The organoleptic properties related to the flavor of this valued product are also due to the presence of a series of compounds in its composition, mainly some carbonyl compounds found in the volatile fraction, although some minor compounds such as phenolic compounds also contribute. However, these properties are greatly affected by the incidence of certain factors, both intrinsic, such as the olive variety, and extrinsic, such as the growing conditions, so that each EVOO has a particular flavor. Furthermore, these flavors are susceptible to change under the influence of other factors throughout the oil's shelf-life, such as oxidation or temperature. This work offers a description of some of the most remarkable compounds responsible for EVOO’s unique flavor and aroma, the factors affecting them, the mechanism that lead to the degradation of EVOO, and how flavors can be altered during the shelf-life of the oil, as well as several strategies suggested for the preservation of this flavor, on which the quality of the product also depends.The research leading to these results was funded by Xunta de Galicia supporting the Axudas Conecta Peme, the IN852A 2018/58 NeuroFood Project and the program EXCELENCIAED431F 2020/12; to Ibero-American Program on Science and Technology (CYTED—AQUA-CIBUS, P317RT0003) and to the Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBI-JTI-2019). The JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The project SYSTEMIC Knowledge hub on Nutrition and Food Security, has received funding from national research funding parties in Belgium (FWO), France (INRA), Germany (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint action of JPI HDHL, JPI-OCEANS and FACCE-JPI launched in 2019 under the ERA-NET ERA-HDHL (nº 696295).info:eu-repo/semantics/publishedVersio

Carotenoids as Natural Colorful Additives for the Food Industry

The application of natural colorants is increasing in the food industry because they are considered safer and healthier than some synthetic pigments. Natural colorants can improve the organoleptic properties of foodstuffs, provide additional benefits such as enhance their nutritional value and/or extend shelf-life. Plants, fungi, bacteria or algae naturally produce different natural colorants, including carotenoids. These compounds are classified into two main groups: pure hydrocarbon carotenes (α- and β-carotenes, lycopene) and oxygenated derivatives of xanthophylls (lutein, zeaxanthin, astaxanthin, fucoxanthin, cryptoxanthin, etc.). Carotenoids have been related with beneficial properties like antioxidant, antidiabetic, antitumor or antimicrobial, so they are a natural and healthy alternative to the use of synthetic colorants. Thus, it is critical to optimize their extraction, by utilizing novel and green techniques, and their stability through encapsulation processes. This chapter aims to review natural sources of carotenoids, strategies to efficiently extract and produce them and their potential application as food colorants

Application of Green Extraction Techniques for Natural Additives Production

During the last decades, consumers have increased the demand for healthier natural foods with lower presence of chemical additives. One reason of this choice is the controversy about chemical additives possible adverse effects. To fulfill market needs, different techniques have been developed to extract compounds from various raw materials to produce natural additives with different properties (preservatives, emulsifiers, or colorants) and bioactivities. In addition, the growing concern about the effects of climate change has led the development of more sustainable techniques to carry out the extraction. The use of new alternative nonconventional, emerging, or green extraction methodologies has gained considerable attention during the last decade. These novel techniques have been applied to minimize any negative changes in the nutritional, physicochemical or sensory properties of the natural source, while at the same time reducing the environmental impact of the process and gaining competitiveness of the world market. For this purpose, new green extraction methods have been proposed and optimized for the reduction of the consumption of raw materials, solvents, and energy. In this chapter, a revision of different types of green extraction techniques is compiled together with the main factor that can affect extraction-process feasibility and the main challenges and future trends for their development

Evaluación del perfil fenólico individual de Calluna vulgaris (L.) y de su potencial bioactivo

En la actualidad, existe una tendencia en el consumo de alimentos más nutritivos y que aporten beneficios para la salud [1]. En este contexto, el consumo de plantas ha demostrado ser beneficioso, debido a la presencia de diversos nutrientes y moléculas bioactivas con propiedades funcionales. Los polifenoles son un grupo de compuestos que, según diversos estudios, han demostrado propiedades antioxidantes, anti-inflamatorias, antimicrobianas y antitumorales, entre otros, ejerciendo efectos terapéuticos sobre diversas enfermedades [1,2]. Así en el presente trabajo se determinó el perfil individual de compuestos fenólicos en los extractos hidroetanólicos e infusiones obtenidas a partir de las flores de Calluna vulgaris (L.); así como las propiedades bioactivas a través de ensayos in vitro de actividad antioxidante y antimicrobiana. Los compuestos fenólicos individuales se analizaron mediante HPLC-DAD-ESI/MS. La actividad antioxidante se evaluó a través de las metodologías de TBARS y OxHLIA; la actividad antimicrobiana se determinó usando el método de microdilución en bacterias Gram-positivas y Gram-negativas, y en hongos; y finalmente, la hepatotoxicidad se estimó usando un cultivo de células primarias no tumorales (PLP2) y aplicando el ensayo de sulforhodamina B. En la evaluación del perfil fenólico individual, en ambos extractos evaluados (hidroetanólico e infusión) fue evidente la presencia de 20 compuestos fenólicos, de los cuales siete fueron identificados como ácidos fenólicos y trece como flavonoides. La quercetina-3-O-ramnosida se destacó como el compuesto principal. Con respecto a la actividad antioxidante, ambos ensayos testados mostraron valores promisorios de EC50, que tradujeron el excelente potencial antioxidante de la especie. Lo mismo sucedió con la actividad antimicrobiana, donde se demostró el potencial bacteriostático, bactericida y fungicida contra las cepas de bacterias y hongos analizados. También fue probado la ausencia de toxicidad del estrato hidroetanólico y la infusión de C. vulgaris. Este estudio concluyó que C. vulgaris es una flor rica en moléculas bioactivas, especialmente flavonoides y ácidos fenólicos, que pueden generar un gran interés en la industria alimentaria y farmacéutica.Los autores agradecen a la FCT, Portugal y FEDER bajo el Programa PT2020 por el apoyo financiero a CIMO (UID/AGR/00690/2019). L. Barros agradece a FCT, P.I., a través del contrato institucional del programa científico de empleo; contrato de investigación de C. Caleja (proyecto AllNatt, POCI- 01-0145-FEDER-030463); y a lo Programa FEDER-Interreg España-Portugal pelo apoyo financiero a través del proyecto 0377_Iberphenol_6_E. Agradecen tambien al Ministerio de Ciencia, Innovación y Universidades por el soporte económico del investigador pre-doctoral Anxo Carreira Casais y a la Xunta de Galicia “Programa de axudas á etapa predoutoral da Xunta de Galicia” por el apoyo financiero a la investigadora pre-doctoral Paula García Oliveira. A la Xunta de Galicia por el soporte financiero de las “Axudas Conecta Peme” al proyecto IN852A 2018/58 NeuroFood.info:eu-repo/semantics/publishedVersio

The use of seaweed in daily diets as a source of nutrientes

Seaweed plays an important role in the biosphere being responsible for most of the production in aquatic ecosystems [1]. Although commonly consumed since ancient times in Asia, their consumption has been increasing in Europe and North America [2]. These species are known for their excellent nutritional value, especially as a protein sources and low lipid and caloric content. In addition, they are rich in several bioactive compounds, such as vitamins, essential fatty acids and phenolic compounds, providing important health benefits to consumers [3]. This work aims to determine ash, proteins, fat, carbohydrates and energy contents, as also the composition in free sugars, organic acids and fatty acids of some seaweeds species, namely Himanthalia elongate L., S.F. Gray; Laminaria ochroleuca Bach.Pyl.; Saccharina latissima L.; Porphyra sp. C.Agardh; Palmaria palmata (L.) Kuntze, and Undaria pinnatifida (Harvey) Suringar. The nutritional aspects were determined using official methodologies for food analysis, while free sugars were identified by HPLC-RI, organic acids by UPFLC-PDA and fatty acids by GC-FID. Proteins stood out as the main macronutrients present, with values that oscillated between 6 and 30 g/100 g of dry weight (dw) for S. latissima and Porphyra sp., respectively. On the other hand, a low lipid content was evident in all the studied seaweed species with values below 1 g/100 g dw, as well as low carbohydrates’ content. The energy values ranged from 218 and 370 kcal/100 g dw for L. ochrouleuca and Porphyra sp, respectively. Furthermore, several compounds of interest were identified, namely free sugars and organic acids, in this case being oxalic acid the only molecule present in all species. Saturated, unsaturated and polyunsaturated fatty acids were also determined, showing a clear heterogeneity of concentrations depending on the species. The present study demonstrates the high potential of these seaweed species as an alternative source of non-animal protein, as well as some molecules with bioactive properties. Thus, the incorporation of this food into the daily diet will contribute for the improvement of a number of functionalities.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2019). L. Barros thanks FCT, P.I., through the institutional scientific employment program-contract for her contract; research contract of C. Caleja (Project AllNatt, POCI- 01-0145-FEDER-030463). The authors are also grateful to Ministerio de Ciencia, Innovación y Universidades for Anxo Carreira-Casais FPU grant; and to Xunta de Galicia for Paula García-Oliveira predoctoral grantinfo:eu-repo/semantics/publishedVersio

Critical Variables Influencing the Ultrasound-Assisted Extraction of Bioactive Compounds—A Review

Ultrasound-assisted extraction (UAE) is a novel methodology, belonging to the so-called “Green Chemistry”, which has gained interest in recent years due to the potential to recover bioactive compounds, especially those from plant matrices. It is widely recognized that the extraction of molecules by UAE gives rise to higher or similar yields than those obtained by traditional extraction methods. UAE has certain advantages inherent to Green Chemistry extraction methods, such as short extraction time and low solvent consumption. The aim of this review is to critically present the different variables and parameters that can be modified in UAE, such as ultrasound power, time, temperature, solvent, and solid to solvent ratio that influence yield and extraction performance