Cell Immobilization for production of lactic acid: Biofilms do it naturally

Interest in natural cell immobilization or biofilms for lactic acid fermentation has developed considerably over the last few decades. Many studies report the benefits associated with biofilms as industrial methods for food production and for wastewater treatment, since the formation represents a protective means of microbial growth offering survival advantages to cells in toxic environments. The formation of biofilms is a natural process in which microbial cells adsorb to a support without chemicals or polymers that entrap the cells and is dependent on the reactor environment, microorganism, and characteristics of the support. These unique characteristics enable biofilms to cause chronic infections, disease, food spoilage, and devastating effects as in microbial corrosion. Their distinct resistance to toxicity, high biomass potential, and improved stability over cells in suspension make biofilms a good tool for improving the industrial economics of biological lactic acid production. Lactic acid bacteria and specific filamentous fungi are the main sources of biological lactic acid. Over the past two decades, studies have focused on improving the lactic acid volumetric productivity through reactor design development, new support materials, and improvements in microbial production strains. To illustrate the operational designs applied to the natural immobilization of lactic acid producing microorganisms, this chapter presents the results of a search for optimum parameters and how they are affected by the physical, chemical, and biological variables of the process. We will place particular emphasis upon the relationship between lactic acid productivity attained by various types of reactors, supports, media formulations, and lactic acid producing microorganisms.Fil: Dagher, Suzanne F.. North Carolina State University; Estados UnidosFil: Ragout, Alicia Leonor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Siñeriz, Faustino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Bruno Bárcena, José M.. North Carolina State University; Estados Unido

European genetic resources conservation in a rapidly changing world

Even though genetic resources represent a fundamental reservoir of options to achieve sustainable development goals in a changing world, they are overlooked in the policy agenda and severely threatened. The conservation of genetic resources relies on complementary in situ and ex situ approaches appropriately designed for each type of organism. Environmental and socioeconomic changes raise new challenges and opportunities for sustainable use and conservation of genetic resources. Aiming at a more integrated and adaptive approach, European scientists and genetic resources managers with long experience in the agricultural crop, animal and forestry domains joined their expertise to address three critical challenges: (1) how to adapt genetic resources conservation strategies to climate change, (2) how to promote in situ conservation strategies and (3) how can genetic resources conservation contribute to and benefit from agroecological systems. We present here 31 evidence-based statements and 88 key recommendations elaborated around these questions for policymakers, conservation actors and the scientific community. We anticipate that stakeholders in other genetic resources domains and biodiversity conservation actors across the globe will have interest in these crosscutting and multi-actor recommendations, which support several biodiversity conservation policies and practices

Temperature effects on cation transport in hereditary stomatocytosis and allied disorders

The conditions known as ‘hereditary stomatocytosis and allied syndromes’ comprise a group of dominantly inherited human haemolytic anaemias characterized by a plasma membrane ‘leak’ to the univalent cations Na and K, an example of a small but growing group of diseases where pathology can be directly attributed to abnormal membrane transport. A number of case reports in the different variants have alluded to temperature-related phenomena, including loss of K on storage at room temperature (giving ‘pseudohyperkalaemia’) and lysis of cells when stored in the cold (‘cryohydrocytosis’). This review collects together published studies of these temperature effects, which show very major differences in the ‘leak’ K transport. Two main variations on normal emerge: a ‘shallow slope’ type, in which the flux shows an abnormally low dependence on temperature in the range 37–20°C, and ‘high minimum’, in which the minimum in this flux, which occurs in normal cells at 8°C, is shifted up to 23°C. These temperature studies provide a powerful method for phenotypic characterization