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Aims: Isolating a novel bacterial source of fructan from a saltern and analysis of its genome to better understand the possible roles of fructans in hypersaline environments. Methods and Results: Bacteria were isolated from crude salt samples originating from Çamaltı Saltern in Western Turkey and screened for fructanogenic traits in high‐salt and sucrose‐rich selective medium. Exopolysaccharide accumulated in the presence of sucrose by isolate OK12 was purified and chemically characterized via HPLC, FT‐IR and NMR, which revealed that it was a levan‐type fructan (β‐2,6 linked homopolymer of fructose). The isolate was taxonomically classified as Bacillus licheniformis OK12 through 16S rRNA gene and whole‐genome sequencing methods. Strain OK12 harbours one levansucrase and two different levanase genes, which altogether were predicted to significantly contribute to intracellular glucose and fructose pools. The isolate could withstand 15% NaCl, and thus classified as a halotolerant. Conclusions: Fructanogenic traits in halotolerant B. licheniformis OK12 are significant due to predicted influx of glucose and fructose as a result of levan biosynthesis and levan hydrolysis, respectively. Significance and Impact of the Study: Fructans from the residents of hypersaline habitats are underexplored compounds and are expected to demonstrate physicochemical properties different from their non‐halophilic counterparts. Revealing fructanogenic traits in the genome of a halotolerant bacterium brings up a new perspective in physiological roles of fructans. [ABSTRACT FROM AUTHOR]

In Turkey, approximately 17.5 million liters of waste baklava syrup (WBS) are generated annually. WBS contains a high amount of sugar; however, it does not find any application. In this study, microbial conversion of WBS to biofuels and bioproducts was investigated. The experiments were performed in shaking flask cultures. WBS was not subjected to any hydrolysis process and was directly used as substrate in the medium, since it was in liquid form. The total sugar content of WBS was determined as 870 g/L. At the optimal concentrations of WBS, 38.6 g/L citric acid by Aspergillus niger , 27.3 g/L levan by Zymomonas mobilis and 8.9 g/L lipids by Rhodotorula glutinis could be produced. The amounts of ethanol produced by S. cerevisiae and Z. mobilis were 129 and 75.2 mL/L, respectively. The maximum absorbances for yellow, red and orange pigments which were produced by Monascus purpureus were determined as 0.7768, 0.928 and 0.835, respectively. Evaluating WBS as a substrate in microbial fermentation studies can contribute to reducing both the medium cost and the environmental pollution problem. This is the first report about the use of WBS as a substrate in microbial studies. [Display omitted] • Waste baklava syrup (WBS) contained a high amount (870 g/L) of total sugar. • WBS was not subjected to any hydrolysis since it was in liquid form. • WBS supported the fermentative production of ethanol, levan, pigment, lipid and citric acid. • WBS allowed the monitoring of pigmentation in the culture due to its light-color. [ABSTRACT FROM AUTHOR]

Fructans are fructose-based oligo- and polysaccharides derived from sucrose that occur in a plethora of Eubacteria and plants. While fructan-producing (fructanogenic) Eubacteria are abundant in hypersaline environments, fructan production by Archaea has never been reported before. Exopolysaccharides accumulated by various Archaea from the Halobacteria class (belonging to the genera of Halomicrobium, Haloferax and Natronococcus) originating from different locations on Earth were structurally characterized as either levans or inulins with varying branching degrees (10%-16%). Thus, we show for the first time in the literature that fructans are produced in all three domains of life, including Archaea. This proof of concept will not only provide insight into Archaeal glycans and evolution but it may also open new frontiers for innovative strategies to overcome the ever-increasing threat of excessive salinization., (Copyright © 2019 Elsevier Ltd. All rights reserved.)