Isolation and characterization of halophilic Archaea able to produce biosurfactants.

Halotolerant microorganisms able to live in saline environments offer a multitude of actual or potential applications in various fields of biotechnology. This is why some strains of Halobacteria from an Algerian culture collection were screened for biosurfactant production in a standard medium using the qualitative drop-collapse test and emulsification activity assay. Five of the Halobacteria strains reduced the growth medium surface tension below 40 mN m(-1), and two of them exhibited high emulsion-stabilizing capacity. Diesel oil-in-water emulsions were stabilized over a broad range of conditions, from pH 2 to 11, with up to 35% sodium chloride or up to 25% ethanol in the aqueous phase. Emulsions were stable to three cycles of freezing and thawing. The components of the biosurfactant were determined; it contained sugar, protein and lipid. The two Halobacteria strains with enhanced biosurfactant producers, designated strain A21 and strain D21, were selected to identify by phenotypic, biochemical characteristics and by partial 16S rRNA gene sequencing. The strains have Mg(2+), and salt growth requirements are always above 15% (w/v) salts with an optimal concentration of 15-25%. Analyses of partial 16S rRNA gene sequences of the two strains suggested that they were halophiles belonging to genera of the family Halobacteriaceae, Halovivax (strain A21) and Haloarcula (strain D21). To our knowledge, this is the first report of biosurfactant production at such a high salt concentration.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Edible films and coatings as carriers of nano and microencapsulated ingredients

Edible films and coatings can provide a protective barrier against physical and mechanical damage, as well as create a controlled atmosphere, by acting as a semi-permeable barrier for gases, vapor and water. These films and coatings also offer the possibility of incorporating different functional ingredients. Nevertheless, the incorporation of these functional compounds is not always easy and new technologies are needed for successful incorporation. One of the possibilities is the use of micro and nanoencapsulation technologies that could help adding the functional compounds by improving their stability and dispersibility, and at the same time decrease the adverse effects that they can have in the films and coatings' properties. This chapter aims to provide a comprehensive review of the use of edible films and coatings for the incorporation of functional ingredients for food applications.Ana Guimarães received support through grant SFRH/BD/103245/2014 from the Portuguese Foundation for Science and Technology (FCT). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation Ana Guimarães received support through grant SFRH/BD/103245/2014 from the Portuguese Foundation for Science and Technology (FCT). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte. This work was, also, funded by the projects: “CVMar+i: Industrial innovation through specific collaborations between companies and research centers in the context of marine biotech nological valorization” (INTERREG V-A España—Portugal—POCTEP 2014–2020, Ref. 0302_CVMAR_I_1_P), “MobFood—Mobilizing scientific and technological knowledge in response to the challenges of the agri-food market” (POCI-01-0247-FEDER-024524), by “MobFood” Consortium, and financed by European Regional Development Fund (ERDF), through the Incentive System to Research and Technological Development, within the Portugal2020 Competitiveness and Internationalization Operational Program.info:eu-repo/semantics/publishedVersio