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Nettle is a highly valued medicinal plant that is still largely neglected, both in terms of nutrition and use for pharmacological purposes. Tinctures, i.e., alcoholic extracts, are becoming increasingly popular nettle products, mainly because they allow better availability of phytochemicals and their stability over a longer period of time. The production of alcoholic extracts is a chemically demanding process that is still usually carried out using conventional techniques, which have numerous drawbacks. The use of green technologies such as ultrasound-assisted extraction (UAE), which is characterized by high efficiency of phytochemical extraction, shorter treatment time, and a much lower environmental footprint, is a suitable and sustainable solution. Therefore, the aim of this study is to determine the influence of the extraction method, conventional and ultrasound (by varying two ultrasound equipment systems), time and ethanol concentration on the extraction of specialized metabolites from nettle powder. Ultrasonic extraction using a probe system significantly contributed to increase the ascorbic acid yield, polyphenolic compounds, and antioxidant capacity of nettle extracts compared to conventional extraction. In addition, when a probe system was used during UAE, significantly less time was required for isolation of individual specialized metabolites compared to ultrasonic extraction in the bath. Ethanol concentration (50 and 80% v/v) also proved to be an important factor in the efficiency of extraction of specialized metabolites, with 80% ethanol being more effective for the isolation of ascorbic acid and pigment compounds (chlorophyll and carotenoids), while 50% v/v for the extraction of polyphenolic compounds. It can be concluded that extraction with the ultrasonic probe system is much more efficient in obtaining higher yields of specialized metabolites from nettle powder in a shorter time (average process duration 5–10 min) both compared to UAE in the bath and classical extraction. However, optimization of the key factors of time, solvent type, and ultrasonic power is necessary to maintain the nutritional quality of the nettle extract in order to obtain a final product with a high specialized metabolites content, antioxidant capacity, and functional value. The future application of alcoholic nettle extracts is based on the fact that these products have significant potential as functional foods and pharmacological preparations for the treatment of a number of but also to strengthen the immune system, mainly due to the rich nutritional composition and high content of various specialized metabolites. The prepared extracts can be safely taken orally by diluting the tinctures with water immediately before ingestion.

This study investigated the effects of pulsed electric field (PEF) (3 kV/cm, 44 pulses, 99 kJ/kg), solvent (H2O or 50 % DMSO) and time (0, 10, 20, 30, 60, 90, 120 and 180 min) on the extraction of Chlorella antioxidant biomolecules and minerals. The results showed that PEF treatment increased the biomolecules recovery. For the extraction time of 120 min, more proteins and polyphenols were obtained using water, while more chlorophyll a and b, and carotenoids were obtained using 50 % DMSO as the extraction solvent. The extracts mineral concentration (PEF vs control) were analysed including Mg, P, Ca, Fe and Zn, and the Relative Nutrient Values results indicated that Chlorella H2O-extracts could be used as a mineral source for different populations. Finally, the fluorescence and scanning electron microscopy revealed the electroporation effect of PEF., This research was funded by the University of Valencia, Spain through the projects OTR2021-21736INVES and OTR2021-21570INVES supported by the University of Vigo, Spain. Moreover, it was partially funded by the EU Commission and BBI-JU Horizon H2020, through the AQUABIOPRO-FIT project (aquaculture and agriculture biomass side stream proteins and bioactive for feed, fitness and health-promoting nutritional supplements) grant number 790956. Jianjun Zhou and Min Wang were supported by a PhD fellowship from the China Scholarship Council (CSC), China (No. 201908420246 and No. 201908420245, respectively). Juan Manuel Castagnini is beneficiary of the grant (ZA21-028) for the requalification of the Spanish university system from the Ministry of Universities of the Government of Spain, modality “Maria Zambrano”, financed by the European Union, NextGeneration EU through the project “Extraction of bioactive compounds from food matrices using innovative and sustainable technologies (EXTRABIO)”. Authors would also like to acknowledge Generalitat Valenciana for the financial support (IDIFEDER/2018/046—Procesos innovadores de extracción y conservación: pulsos eléctricos y fluidos supercríticos) through the European Union ERDF funds (European Regional Development Fund)

Estudios in vivo e in vitro han demostrado que las antocianinas provenientes de los arándanos ejercen efectos biológicos beneficiosos sobre la salud de los consumidores. Existen métodos de análisis in vitro que permiten evaluar la estabilidad de las antocianinas en relación con la interacción de los distintos componentes de las matrices alimentarias, el pH, la temperatura, presencia de inhibidores o potenciadores de absorción y presencia de enzimas. El objetivo del trabajo fue poner a punto la metodología de digestión in vitro y evaluar la biodisponibilidad in vitro de antocianinas presentes en jugo de arándanos y un snack formulado con jugo de arándanos y manzana. Los resultados indican que si bien hay una pérdida de antocianinas durante el proceso digestivo, éstas son capaces de atravesar todas las etapas y llegar al intestino, posibilitando la liberación controlada de estos antioxidantes presentes en el jugo de arándano y en el snack desarrollado. In vivo and in vitro studies have shown that blueberry anthocyanins exert beneficial biological effects on consumers health. In vitro methodology allows to evaluate the stability of the anthocyanins in relation to the interaction of the different components of the dietary matrices, the pH, the temperature, the presence of inhibitors or absorption enhancers and the presence of enzymes. The aims of this research were to develop a methodology of in vitro digestion and to evaluate the in vitro bioavailability of anthocyanins present in blueberry juice and in a snack formulated with blueberry juice and apple. The results indicate that, although there is a loss of anthocyanins during the digestive process, they are able to cross all the stages and reach the intestine, allowing controlled release of these antioxidants present in blueberry juice and the snack. Estudos in vivo e in vitro têm demonstrado que as antocianinas dos mirtilos exercem efeitos biológicos benéficos sobre a saúde dos consumidores. Existem métodos de análise in vitro que permitem avaliar a estabilidade das antocianinas em relação à interação dos diferentes componentes das matrizes alimentares, o pH, a temperatura, a presença de inibidores ou potenciadores de absorção e a presença de enzimas. O objetivo do trabalho foi ajustar a metodologia de digestão in vitro e avaliar a biodisponibilidade in vitro de antocianinas presentes em suco de mirtilos e um snack formulado com suco de mirtilos e maçã. Os resultados indicam que, embora haja uma perda de antocianinas durante o processo digestivo, elas são capazes de atravessar todos os estágios e chegar ao intestino, permitindo a liberação controlada destes antioxidantes presentes no suco de mirtilos e no snack desenvolvido.

Resumen: Antecedentes: Los arándanos y productos de arándano tienen alto valor nutricional, especialmente por su alto contenido de antocianinas. Estas son potentes antioxidantes y poseen alta capacidad de secuestrar radicales libres. Así, los arándanos y productos de arándanos han resultado atractivos para los consumidores interesados en alimentos funcionales. Sin embargo, los tratamientos térmicos y posterior almacenamiento de productos alimenticios influyen en el contenido de antocianinas. La cinética de degradación de las antocianinas puede ser evaluada desde una perspectiva termodinámica, basada en funciones como energía libre, entalpía, entropía y energía de activación. Objetivos: Se estudió el efecto de la pasteurización y la estabilidad de antocianinas presentes en jugos de arándanos, sin pasteurizar y pasteurizados, durante el almacenamiento. Métodos: Jugos de arándanos sin pasteurizar y pasteurizados fueron almacenados a -18, 0, 5 y 10°C durante 148 días. A intervalos de tiempos se cuantificó la concentración de antocianinas monoméricas totales. Se realizó un Análisis de Componentes Principales y los resultados experimentales se ajustaron a modelos cinéticos de orden cero y uno, y a los modelos de Arrhenius y Eyring. Resultados: La pasteurización provocó disminución del 28,5% en la concentración inicial de antocianinas monoméricas totales, mientras que para todas las temperaturas estudiadas, la disminución de antocianinas en función del tiempo de almacenamiento siguió una cinética de primer orden. En el jugo sin pasteurizar, la constante de velocidad de degradación varió entre 0,0080 - 0,0084 días-1 y el tiempo de vida media, entre 75 - 87 días. En el jugo pasteurizado, la constante de velocidad de degradación varió entre 0,0023 - 0,0060 días-1 y el tiempo de vida media, entre 116-301 días. En éste la energía de activación, la energía libre de Gibbs, entalpía y entropía de activación fueron 44,66 kJ/mol, 83,80 kJ/mol, 42,35 kJ/mol y -139,09 J/mol.K, respectivamente”. Conclusiones: El tratamiento de pasteurización provocó disminución del 28,5% en la concentración de antocianinas monoméricas totales iniciales de los jugos de arándano. La estabilidad de las antocianinas durante el almacenamiento fue mayor en los jugos pasteurizados, siendo mayor cuando se almacenaron a 0°C; mientras que en los jugos pasteurizados almacenados a -18°C las antocianinas mostraron menor estabilidad. Abstract: Background: The blueberries and blueberry products has great nutritional value, primarily because it has high anthocyanin content. Anthocyanins are potent antioxidants and have high radical-scavenging activities. Thus, the blueberry and blueberry products has become very appealing to consumers interested in functional foods. However, the anthocyanins content is affected by heat treatment and subsequent storage. The kinetics degradation of anthocyanins can be evaluated from a thermodynamic perspective, based on activation functions such as free energy, enthalpy, entropy and activation energy. Objectives: pasteurization effect and anthocyanins stability were studied during storage of pasteurized and non-pasteurized blueberries juices. Methods: Pasteurized and non-pasteurized blueberries juices were store at -18, 0, 5 and 10°C during 148 days. Total monomeric anthocyanins concentration was quantified at different times. Principal Components Analysis was performed and experimental results were adjusted to zero and first-order kinetic models as well as to Arrhenius and Eyring ones. Results: A decrease in total monomeric anthocyanins original concentration was 28.5 % due to pasteurization while for all temperatures studied, the reduction followed a first-order kinetic during storage. Degradation rate constant varied between 0.0080 - 0.0084 days-1 and half-life, 75 - 87 days for non-pasteurized juices, whereas these parameters were among 0.0023 - 0.0060 days-1 and 116 - 301 days, respectively for pasteurized ones. Activation energy was 44.66 kJ/mol while Gibbs free energy, enthalpy and entropy were 83.80 kJ/mol, 42.35 kJ/mol and -139.09 J/mol. K respectively, for the latter juices. Conclusions: Pasteurization caused in a 28.5 % loss of initial total monomeric anthocyanins. Anthocyanins stability was higher in pasteurized blueberries juices and resulted even bigger when store at 0°C, while in pasteurized juices stored -18 ° C were less stable anthocyanins.

The production of dried snacks with high nutritional value represents a valid alternative to use the kiwifruit waste as undersized fruits, with a positive economic impact on the entire production chain. Therefore, this work aimed to evaluate the effect of pulsed electric field - PEF (200 V/cm) and/or osmotic dehydration – OD pre-treatments on drying kinetics (50, 60, 70 °C), texture, colour, and sensorial properties of yellow kiwifruit snacks. The drying kinetics were significantly influenced both by applied treatment and drying temperature. The firmness of the kiwifruit snacks was improved by the combination of PEF/OD pre-treatments. In general, drying temperature of 70 °C and the use of combined pre-treatments seem to be a good compromise to reduce drying time and obtain products with high quality in terms of colour, firmness, and overall acceptability.

Shrimp side streams represent an important natural source of astaxanthin. Optimization of the astaxanthin extraction process from shrimp side streams is of great importance for the valorization of crustacean side streams and the development of astaxanthin-related products. The combined and independent effects of two innovative extraction technologies (pulsed electric fields (PEFs) and accelerated solvent extraction (ASE)) alone and/or combined in a sequential step, using two different solvents on astaxanthin extraction from two shrimp species, were evaluated. Astaxanthin content in the extracts of shrimp side streams was determined by both spectrophotometric and HPLC assays, being the determination of the carotenoid profiles performed by HPLC analysis. Compared to a solvent extraction control procedure, the astaxanthin content was increased after ASE and PEF treatments, for both shrimp species, independently of the solvent used. The highest recovery (585.90 µg/g) was obtained for the species A. antennatus, with the solvent DMSO when PEF and ASE were combined, while the increase in antioxidant capacity varied depending on the solvent used. HPLC analysis of the samples revealed the presence of unesterified (all-E) astaxanthin, four unesterified Z isomers of astaxanthin and many unresolved astaxanthin esters. Both technologies are useful tools to recover antioxidant valuable carotenoids such as astaxanthin from shrimp side streams. Universidad de Valencia OTR202- 22808INVES European Commission 790956 Ministerio de Universidades ZA21-028 Generalitat Valenciana IDIFEDER/2018/046