Hydrogen sulfide sorption activities of manganese oxide and Mn-Fe-Cu mixed oxide sorbents were examined in a fixed bed reactor. Sulfur retention capacity of Mn-O sorbent was found to be quite high at 600 °C both in the absence and presence of hydrogen gas (0.17 and 0.14 g S/g sorbent, respectively). This sorbent has a high porosity and a relatively high surface area. Best regeneration temperature of this sorbent was found as 700 °C, with a gas stream containing 6% oxygen in nitrogen. Mn-Fe-Cu mixed oxide sorbent had a lower sulfur retention capacity (0.07 g S/g sorbent). However, both of these sorbents gave quite high initial sorption rate constants, resulting very sharp breakthrough curves. Deactivation model was shown to give good agreement with the experimental H2S breakthrough curves.

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Prokaryotic communities and physico-chemical characteristics of 30 brine samples from the thalassohaline Tuz Lake (Salt Lake), Deep Zone, Kayacik, Kaldirim, and Yavsan salterns (Turkey) were analyzed using 16S rRNA amplicon sequencing and standard methods, respectively. Archaea (98.41% of reads) was found to dominate in these habitats in contrast to the domain Bacteria (1.38% of reads). Representatives of the phylum Euryarchaeota were detected as the most predominant, while 59.48% and 1.32% of reads, respectively, were assigned to 18 archaeal genera, 19 bacterial genera, 10 archaeal genera, and one bacterial genus that were determined to be present, with more than 1% sequences in the samples. They were the archaeal genera Haloquadratum, Haloarcula, Halorhabdus, Natronomonas, Halosimplex, Halomicrobium, Halorubrum, Halonotius, Halolamina, Halobacterium, and Salinibacter within the domain Bacteria. The genera Haloquadratum and Halorhabdus were found in all sampling sites. While Haloquadratum, Haloarcula, and Halorhabdus were the most abundant genera, two uncultured Tuz Lake Halobacteria (TLHs) 1 and 2 were detected in high abundance, and an additional uncultured haloarchaeal TLH-3 was found as a minor abundant uncultured taxon. Their future isolation in pure culture would permit us to expand our knowledge on hypersaline thalassohaline habitats, as well as their ecological role and biomedical and biotechnological potential applications.

Aim: This study aimed to isolate moderately halophilic bacteria from salted goat skins, to characterize these microorganisms and to determine their industrially important enzymes such as amylase, catalase, oxidase, caseinase, cellulase, DNase, lipase, lecithinase, protease, pullulanase, urease, phospholipase, xylanase and β-galactosidase. Methods: Enzymes of these bacteria, isolated from skin samples belonging to eight countries and identified using phenotypic and genotypic methods, were examined in agar media. Results: Thirty-nine isolates were fairly similar to species of genera Staphylococcus, Bacillus, Salinicoccus, Gracilibacillus, Chromohalobacter and Halomonas. Various carbon sources were utilized, and all isolates produced enzyme. Enzyme-producing species were Staphylococcus saprophyticus subsp. saprophyticus, Staphylococcus arlettae, Bacillus pumilus, Gracilibacillus dipsosauri, Salinicoccus roseus, Bacillus licheniformis, Chromohalobacter beijerinckii, Staphylococcus xylosus, Halomonas eurihalina, Staphylococcus equorum subsp. equorum, Halomonas zhanjiangensis, Halomonas venusta and Chromohalobacter canadensis. Fairly high percentage of isolates produced protease (87%) and catalase (100%). While more than 50% of isolates produced lipase (64%), β-galactosidase (59%) and oxidase (56%), less than 50% of isolates produced urease (46%), caseinase (28%), amylase (26%), lecithinase (8%) and cellulase (5%). Conclusion: We detected that moderately halophilic bacteria on skins produced important enzymes, which may be used in diverse industrial applications in leather, feed, detergent, paper, food, chemical, medical, pharmaceutical, textile industries.

Soaked hides and skins may contain different species of family Enterobacteriaceae, originating from animal's feces, soil, and water. Some species of this family may be pathogenic to humans and animals. Hence, phenotypic characteristics and antibiotic susceptibilities of Ewingella americana and Kluyvera intermedia belonging to Enterobacteriaceae were explained in this study. While Ewingella americana was isolated from only one soaked hide, Kluyvera intermedia was isolated from both soaked hide and skin. Phenotypic characterization of these isolates was performed using API 20E test kit. Antibiotic susceptibilities of these isolates were examined by Kirby Bauer Disc Diffusion Test using piperacillin/tazobactam (110µg), amoxicillin/clavulanate (30µg), ampicillin/sulbactam (20µg), amikacin (30µg), tobramycin (10µg), kanamycin (30µg), gentamicin (10µg), streptomycin (10µg), ampicillin (10µg), imipenem (10µg), meropenem (10µg), cefoxitin (30µg), cefuroxime sodium (30µg), ceftazidime (30µg), cephalothin (30µg), ceftriaxone (30µg), norfloxacin (10µg), nalidixic acid (30µg), ofloxacin (5µg), ciprofloxacin (10µg), sulfamethoxazole-trimethoprim (25µg), aztreonam (30µg), chloramphenicol (30µg), tetracyline (30µg). Ewingella americana was resistant against aztreonam, ceftazidime, ceftriaxone but this isolate was intermediate susceptible against cefuroxime sodium, ampicillin, nalidixic acid, tetracyline and chloramphenicol. Kluyvera intermedia was found to be resistant against streptomycin, cephalothin, aztreonam, and ampicillin but it was intermediate susceptible to amikacin, kanamycin, chloramphenicol, imipenem, ceftazidime, ceftriaxone, amoxicillin/clavulanate and ciprofloxacin. Moreover, both isolates were found to be susceptible to other antibiotics. Therefore, effective antibacterial applications should be applied to kill these antibiotic resistant bacteria.