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Salt-tolerant enzymes produced by halophilic and halotolerant microorganisms have been proposed to be used in various applications that involve high saline conditions. Considering their biotechnological significance and the current need for more efficient producers of such catalysts, the present study aimed to evaluate the extracellular proteolytic, esterolytic, cellulolytic and xylanolytic activities of some halotolerant strains, and to characterize their functional parameters. A total of 21 bacterial and fungal strains belonging to the genera Bacillus, Virgibacillus, Salinivibrio, Salinicoccus, Psychrobacter, Nocardiopsis, Penicillium, Aspergillus, and Emericellopsis were assayed by quantitative methods. Among them, the members of the Bacillus genus exhibited the highest catalytic activities. The exoenzymes produced by three selected Bacillus strains were active over wide ranges of salinity, temperature and pH. Proteases were active at 20–80 °C, pH 6–10, and 0–1 M NaCl, while esterases showed good catalytic activities at 20–80 °C, pH 7.5–10, and 0–4 M NaCl. Cellulases and xylanases were active at 20–80 °C, pH 5–10, and 0–5 M NaCl. Due to such properties, these hydrolases could be used in a newly proposed application, namely to clean aged consolidants and organic deposits accumulated over time from the surfaces of salt-loaded wall paintings.

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Nitraria schoberi L. (Nitrariaceae) is a halophytic plant with a continuous range in Central Asia and with only two populations in the westernmost distribution limit of species, in Romania. Currently, there is no documented explanation for the species’ presence in Europe, outside the main distribution area. Considering that marginal populations genetics are important in establishing range limits and species adaptative potential, genetic diversity was assessed using Inter-simple sequence repeat markers (ISSR). Both the Shannon’s Information Index (I) and Expected Heterozygosity (He) suggested a relatively low level of genetic diversity within the two populations. However, the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) dendrogram and Principal Coordinates Analysis clearly distinguished the two populations. Our presumptions, based on current results, are that the marginal westernmost population of N. schoberi was established due to the unique conditions from the “islands of desert” developed in a temperate continental climate. The European establishment of this species was likely accidental and probably due to ornithochory. Genetic relatedness between populations could be a consequence of their common origin, presumably from proximal Asian N. schoberi populations, while the separation can be explained by the lack of genetic material exchange between the two populations.