Preparation and characterization of licorice‐chitosan coatings for postharvest treatment of fresh strawberries

Several plant extracts are being investigated to produce edible coatings, mainly due to their antioxidant and antimicrobial activities. In this study, licorice root extracts were produced by ultrasound‐assisted extraction and were combined with chitosan to elaborate edible coatings. Different solvents and temperatures were used in the extraction process, and the antioxidant and antimicrobial activity of the extracts were assessed. The most bioactive extracts were selected for the development of the edible coatings. The rheological properties of the coatings were studied, and they were applied on strawberry to evaluate their physicochemical and microbiological properties. The addition of licorice extract to chitosan resulted in positive effects on the rheological properties of the coatings: the incorporation of phytochemicals to chitosan decreased the shear stress and improved the restructuring ability of the coating solutions. The films presented a reduction of the Burger model parameter, indicating a reduction of rigidity. Furthermore, the strawberry coated with chitosan and licorice extract maintained good quality parameters during storage and showed the best microbiological preservation in comparison with controls. Hence, the use of chitosan with licorice extract is a potential strategy to produce edible coating for improving the postharvest quality of fruitsThis research was funded by Comunidad Autónoma de Madrid, grant number P2013/ABI27, project Bolívar Gana con Ciencia, MinCiencias Contract 368-2019 and Programa Nacional de Innovación Agraria—PNIA of Perú, Contract: No. 152-2018-INIA-PNIA-PASANTI

Supercritical antisolvent particle precipitation and fractionation of rosemary (Rosmarinus officinalis L.) extracts

The simultaneous fractionation and precipitation of an ethanolic extract of rosemary (Rosmarinus officinalis L.) using supercritical carbon dioxide anti-solvent technique was studied, with the target of separate in two different fractions the key antioxidants of rosemary (i.e. rosmarinic acid, carnosic acid and carnosol). The effect of pressure and temperature on the fractionation process was investigated, together with the morphology and particle size distribution of the precipitates. Additionally, the chemical composition of the oleoresins were analyzed and reported. In the range of pressures (9-20 MPa) and temperatures (313-333 K) used in this work, the precipitates presented a 2-3 fold enrichment of rosmarinic acid, while carnosic acid and carnosol were concentrated (2-3 fold enrichment) in the oleoresin fractions. Furthermore, in general, oleoresins presented higher antioxidant activity than precipitates. Particles produced with a nozzle of diameter 101.6 μm were smaller and more spherical with increasing pressure (mean value 4-10 μm at 20 MPa) and decreasing temperatureThe authors gratefully acknowledge the financial support from Ministerio de Economía y Competitividad of Spain (Proyect AGL2016- 76736-C3-1-R). Somaris E. Quintana is grateful for the funding provided by Gobernación de Bolivar and Fundación Ceiba, Colombia, in the project “Bolívar Gana con Cienci

Fractionation and precipitation of licorice (Glycyrrhiza glabra L.) phytochemicals by supercritical antisolvent (SAS) technique

Supercritical anti-solvent precipitation (SAS) using carbon dioxide is a novel technique that can be used to produce powdered ingredients in small size particles, facilitating their incorporation into food matrices. In this work, the SAS precipitation of a licorice root ethanolic extract was studied. SAS assays were carried out at 15–20 MPa, 308.15 and 313.15 K, and two different concentrations (9.6 and 14.2 mg/ml) of the ethanolic licorice extract. In the range of conditions investigated, SAS pressure and temperature did not affect significantly the precipitation yield, but phytochemicals recovery was higher with the lower licorice extract concentration. Moreover, the fractionation of licorice bioactives (liquiritin, liquiritigenin, isoliquiritigenin, glabridin and glycyrrhizic acid) was assessed, together with the content of total phenolic compounds and antioxidant activity of the powders and oleoresin by-products obtained. In this respect, precipitates and oleoresins presented significant differences in the concentration of some licorice bioactives, and higher antioxidant activity was observed in precipitates. Additionally, significant effect of pressure, temperature and licorice extract concentration on the morphology and particle size of precipitates was observed, recovering smaller and more regular particles at 15–20 MPa, 313.15 K and 9.6 mg/ml licorice extract concentration, attaining satisfactory yield and antioxidant activityThe authors gratefully acknowledge the financial support from Ministerio de Economía y Competitividad of Spain (Projects AGL2017-89055-R and AGL2016-76736-C3-1-R). Somaris E. Quintana is grateful for the funding provided by Gobernación de Bolivar and Fundación Ceiba, Colombia, in the project “Bolívar Gana con Ciencia

Ultrasound-assisted extraction and bioaccessibility of saponins from edible seeds: quinoa, lentil, fenugreek, soybean and lupin

This Accepted Manuscript is available for reuse under a CC BY-NC-ND licence after the 12 month embargo periodThe efficient production of saponin-rich extracts is of increasing interest due to the bioactive properties that have being demonstrated for these compounds. However, saponins have a poor bioavailability. In this respect, the knowledge about the bioaccessibility of saponins as a first step before bioavailability has been scarcely explored. In this study, the production of ultrasound-assisted extracts of saponins from edible seeds (quinoa, soybean, red lentil, fenugreek and lupin) was carried out with ethanol, ethanol:water or water. Extraction yield, total saponin (TSC), fat and total phenolics content (TPC) were determined. Then, the bioaccessibility of saponins after the in vitro gastrointestinal digestion of the extracts was determined and the effect of TPC and fat in the extracts on bioaccessibility was evaluated. The highest saponin-rich extracts were obtained by ethanol, being fenugreek and red lentil the richest extracts (12% and 10%, respectively). Saponins from ethanol:water extracts displayed variable bioaccessibility (from 13% for fenugreek to 83% for lentil), but a bioaccessibility closer to 100% was reached for all ethanol extracts. Correlation studies showed that TPC of the extracts negatively affected the bioaccessibility of saponins, whereas fat of the extracts enhanced this parameter. As summary, ultrasound-assisted extraction is shown as an efficient method for obtaining saponin-rich extracts from edible seeds, being ethanol the most advantageous solvent due to the richness of saponins and the successful bioaccessibility from these extracts, likely caused by the co-extracted fat with ethanol. Regardless of the extracts, phenolic compounds or fat may hinder or enhance the bioaccessibility of saponins, respectively. Additionally, an adequate balance between saponins to lipids has shown to be relevant on such an effectThis work was supported by the Ministerio de Economía y Competitividad, Spain (AGL2016-76736-C3-1-R) and the Community ofMadrid, Spain (ALIBIRD-CM S2013/ABI-2728). Joaquín Navarro del Hierro thanks the Ministerio de Educación, Cultura y Deporte forfunding his research with a FPU predoctoral contract (FPU 15/04236).Teresa Herrera thanks the Community of Madrid for her contract (Fondo Social Europeo, Programa Operativo de Empleo Juvenil eIniciativa de Empleo Juvenil YEI

Antioxidant and antimicrobial assessment of licorice supercritical extracts

Licorice (Glycyrrhiza glabra L.) is a plant used widely in herbal medicines due to their several biological potentials. The supercritical extraction of licorice roots was investigated to assess the antioxidant and antimicrobial activity of the extracts. Extraction conditions were pressures from 15 to 40 MPa, 313.15 and 333.15 K, and ethanol cosolvent in the range of 0 to 20% mass. In the case of high-pressure extractions using pure carbon dioxide (CO2) fractionation of the supercritical extract was accomplished in a two-cell decompression system. Fractionation was carried out with the aim to examine the potential separation of the antioxidant and antimicrobial licorice compounds and thus increase the bioactive properties of the fractions obtained in each separation cell. Main licorice bioactive compounds, liquiritin, liquiritigenin, glycyrrhizin, isoliquiritigenin and glabridin, were identified by HPLC and quantified using standards. Extracts obtained with supercritical CO2 and ethanol cosolvent contain the higher amounts of phenolic compounds and also the higher antioxidant activity but exhibit low or even no antimicrobial activity. Using pure CO2 at high pressure coupled with the on-line fractionation of the extract, two samples were obtained which showed, respectively, lower phenolic compounds content and good antimicrobial capacity (first fraction) and higher phenolic compounds content and antioxidant capacity (second fraction). Thus, the advantages of supercritical on-line fractionation are demonstrated in the extraction of Licorice rootsThe authors gratefully acknowledge the financial support from Ministerio de Economía y Competitividad of Spain (Projects AGL2016-76736-C3-1-R and AGL2015-64522-C2-R

Severity of bovine tuberculosis is associated with co-infection with common pathogens in wild boar

Co-infections with parasites or viruses drive tuberculosis dynamics in humans, but little is known about their effects in other non-human hosts. This work aims to investigate the relationship between Mycobacterium bovis infection and other pathogens in wild boar (Sus scrofa), a recognized reservoir of bovine tuberculosis (bTB) in Mediterranean ecosystems. For this purpose, it has been assessed whether contacts with common concomitant pathogens are associated with the development of severe bTB lesions in 165 wild boar from mid-western Spain. The presence of bTB lesions affecting only one anatomic location (cervical lymph nodes), or more severe patterns affecting more than one location (mainly cervical lymph nodes and lungs), was assessed in infected animals. In addition, the existence of contacts with other pathogens such as porcine circovirus type 2 (PCV2), Aujeszky's disease virus (ADV), swine influenza virus, porcine reproductive and respiratory syndrome virus, Mycoplasma hyopneumoniae, Actinobacillus pleuropneumoniae, Haemophilus parasuis and Metastrongylus spp, was evaluated by means of serological, microbiological and parasitological techniques. The existence of contacts with a structured community of pathogens in wild boar infected by M. bovis was statistically investigated by null models. Association between this community of pathogens and bTB severity was examined using a Partial Least Squares regression approach. Results showed that adult wild boar infected by M. bovis had contacted with some specific, non-random pathogen combinations. Contact with PCV2, ADV and infection by Metastrongylus spp, was positively correlated to tuberculosis severity. Therefore, measures against these concomitant pathogens such as vaccination or deworming, might be useful in tuberculosis control programmes in the wild boar. However, given the unexpected consequences of altering any community of organisms, further research should evaluate the impact of such measures under controlled conditions. Furthermore, more research including other important pathogens, such as gastro-intestinal nematodes, will be necessary to complete this picture

Comparison between essential oils and supercritical extracts into chitosan-based edible coatings on strawberry quality during cold storage

Plant extracts are being studied in the development of novel edible food coatings. The antioxidant and antimicrobial compounds that naturally occur in some plants are the key substances that contribute to preserving food quality. Besides the plant material, the method utilized to produce the extract influences its chemical and preservative characteristics. In general, hydrodistillation produce plant products (essential oils) that are well recognized for containing high concentration of antioxidant or antimicrobial volatile compounds. Supercritical fluid technology produces high quality bioactive extracts with higher yield but lower concentration of volatile compounds, in comparison with hydrodistillation. In this work, six different natural extracts of five different plants were produced by hydrodistillation and supercritical fluid extraction, and their antioxidant and antimicrobial activities were compared. The most active extracts were used to produce chitosan-based edible coatings with the aim of assessing the effect of essential oils versus supercritical extracts on the preservation of strawberriesThe authors gratefully acknowledge the financial support from Comunidad de Madrid through the Programa de I+D en Tecnologías, Spain (ALIBIRD-CM S2013/ABI-2728). Somaris E. Quintana is grateful for the funding provided by Gobernación de Bolivar and Fundación Ceiba, Colombia. Olimpia Llalla is grateful to Programa Nacional de Innovación Agraria-PNIS of Perú (Contract No. 152-2018-INIA-PNIAPASANTIA

Procedimiento para la obtención de extracto de lúpulo y extracto obtenido

La presente invención se refiere a un procedimiento para la obtención de extracto de lúpulo enriquecido en isoxantohumol, y al extracto obtenido mediante dicho procedimiento.Peer reviewedUniversidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas (España), Fundación para la Investigación Biomédica del Hospital Universitario de la PâzA1 Solicitud de patente con informe sobre el estado de la técnic

Extraction of thymol from different varieties of thyme plants using green solvents

[Background]: Thymol (2-isopropyl-5-methylphenol) is the main monoterpene phenol found in thyme essential oil. This compound has revealed several biological properties, including antibacterial, anti-inflammatory and antioxidant activities. In this work, a comparison was made between the performance of different green solvents (ethanol, limonene and ethyl lactate), by pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE) at different conditions, to extract thymol from three different varieties of thyme (Thymus vulgaris, Thymus zygis and Thymus citriodorus). Additionally, new solubility data of thymol in limonene and ethanol at ambient pressure and temperatures in the range 30-43 °C are reported. [Results]: The highest thymol recoveries were attained with T. vulgaris (7-11 mg g-1). No thymol could be quantified in the PLE samples of T. citriodorus. The highest concentrations of thymol in the extracts were obtained with limonene. Thymol is very soluble in both solvents, particularly in ethanol (~900 mg g-1 at ~40 °C), and is the main compound (in terms of peak area) present in the essential oil extracts obtained. [Conclusion]: The three solvents show good capacity to extract thymol from T. vulgaris and T. zygis by PLE. Although PLE proved to be a suitable technology to extract thymol from thyme plants, the highest concentrations of thymol were obtained by SFE with supercritical CO2.The authors gratefully acknowledge the financial support from Ministerio de Ciencia e Innovación (project 25506 FUN-C-FOOD ) and Comunidad Autónoma de Madrid (ALIBIRD- CM, project S2013/ABI-2728). DVB thanks Consejo Superior de Investigaciones Científicas (CSIC) of Spain for a JAE-pre fellowship.Peer Reviewe