A graminan type fructan from Achyranthes bidentata prevents the kidney injury in diabetic mice by regulating gut microbiota.

Diabetic kidney disease (DKD) is the main cause of end-stage renal disease, and few therapeutic options are available. The root of Achyranthis bidentatae (AB) is commonly used for DKD treatment in Traditional Chinese medicine. However, its mechanisms are still unclear. Here, a graminan type fructan ABPW1 with molecular weight of 3998 Da was purified from AB. It was composed of ß-1,2-linked Fruf, ß-2,6-linked-Fruf and ß-1,2,6-linked-Fruf backbone, and terminated with T-Glcp and 2-Fruf residues. ABPW1 protected against kidney injuries and intestinal barrier disruption in Streptozotocin (STZ)/High fat diet (HFD) mice. It could modulate gut microbiota composition, evidenced by a rise in the abundance of Bacteroide and decreases of Rikenella, Alistipes, Laedolimicola and Faecalibaculum. ABPW1 intervention promoted short chain fatty acids (SCFAs) production in STZ/HFD mice, especially propionate and isobutyric acid. Antibiotic treatment further demonstrated the key role of gut microbiota in the renal protective action of ABPW1. In addition, in vitro simulated digestion and fermentation together with in vivo fluorescent labeling studies demonstrated ABPW1 was indigestible in upper digestive tract but could reach the colon and be degraded into SCFAs by gut microbiota there. Overall, these data suggested ABPW1 has the potential application on DKD prevention.

Potential of fructans as natural cryoprotectant agents in plant cryopreservation: concept validation on Arabidopsis thaliana L.

BACKGROUND: Today, synthetic chemicals are used in vitrification solutions for cryopreservation studies to mimic natural cryoprotectants that supply tolerance to organisms in nature against freezing stress. In the case of plants, PVS2, containing glycerol, dimethyl sulfoxide (Me2SO), ethylene glycol and sucrose, is considered as the golden standard for successful cryopreservation. However, Me2SO can generally cause toxicity to certain plant cells, adversely affecting viability after freezing and/or thawing. Hence, the replacement (or substantial reduction) of Me2SO by cheap, non-toxic and natural cryoprotectants became a matter of high priority to vitrification solutions or reducing their content gained escalating importance for the cryopreservation of plants. Fructans, sucrose derivatives mainly consisting of fructose residues, are candidate cryoprotectants. OBJECTIVE: Inspired by their protective role in nature, we here explored, for the first time, the potential of an array of 8 structurally different fructans as cryoprotectants in plant cryopreservation. MATERIALS AND METHODS: Arabidopsis thaliana L. seedlings were used as a model system with a one-step vitrification method. PVS2 solutions with different Me2SO and fructan contents were evaluated. RESULTS: It was found that branched low DP graminan, extracted from milky stage wheat kernels, led to the highest recovery (85%) among tested fructans with 12.5% Me2SO after cryopreservation, which was remarkably close to the viability (90%) observed with the original PVS2 containing 15% Me2SO. Moreover, its protective efficacy could be further optimized by addition of vitamin C acting as an antioxidant. CONCLUSION: Such novel formulations offer great perspectives for cryopreservation of various crop species. Doi.org/10.54680/fr24410110512.

Integrated Mechanism of Immune Response Modulation by Arctium Lappa L. Fructans Based on Microbiome and Metabolomics Technologies.

Arctium lappa L. is widely consumed for its various biological effects, and polysaccharides are its main functional components. The present study aimed to evaluate the immunoregulatory effects of the main polysaccharides from burdock (ALP-1) and reveal the underlying mechanisms. ALP-1 consisted of fructose and glucose (14.57:1) and had a molecular weight of 2757 Da, with typical characteristics of (1 → 2)-linked linear fructans. Oral intake of ALP-1 significantly increased the number of colonic goblet cells, serum immunoglobulin A and immunoglobulin G levels, and fecal secretory immunoglobulin A content as well as up-regulated antioxidant enzymes and increased short chain fatty acid production. In addition, ALP-1 administration regulated pro/anti-inflammatory cytokines (i.e., interleukin (IL)-1ß, IL-6, tumor necrosis factor-α, interferon-γ, and IL-10), intestinal microbiota structure, and the spatial information on key metabolites. Some gut-microbiota-mediated metabolic processes were also significantly altered. These results indicated that ALP-1 could exert beneficial effects on immune responses and intestinal health in healthy mice.

Prebiotic levan type fructan from Bacillus subtilis PR-C18 as a potent antibiofilm agent: Structural elucidation and in silico analysis.

The global demand for therapeutic prebiotics persuades the quest for novel exopolysaccharides that can retard the growth of pathobionts and healthcare-associated pathogens. In this regard, an exopolysaccharide (3.69 mg/mL) producing strain showing prebiotic and antibiofilm activity was isolated from indigenous pineapple pomace of Tripura and identified as Bacillus subtilis PR-C18. Zymogram analysis revealed EPS PR-C18 was synthesized by levansucrase (∼57 kDa) with a maximal activity of 4.62 U/mg. Chromatography techniques, FTIR, and NMR spectral data revealed the homopolymeric nature of purified EPS with a molecular weight of 3.40 × 104 Da. SEM and rheological study unveiled its microporous structure and shear-thinning effect. Furthermore, EPS PR-C18 showed remarkable emulsification, flocculation, water retention, water solubilization, and antioxidant activity. DSC-TGA data demonstrated its high thermostability and cytotoxicity analysis verified its nontoxic biocompatible nature. In addition, the antibiofilm activity of EPS PR-C18 was validated using molecular docking, molecular simulation, MM-GBSA and PCA studies, which exhibited its strong binding affinity (-20.79 kcal/moL) with PelD, a virulence factor from Pseudomonas aeruginosa. Together, these findings support the future exploitation of EPS PR-C18 as an additive or adjuvant in food and pharmaceutical sectors.

Determination of Molecular Dimensions of Carbohydrate Polymers (Polysaccharides) by Size Exclusion Chromatography (SEC).

Calibrated size exclusion chromatography (SEC) is a useful tool for the analysis of molecular dimensions of polysaccharides. The calibration takes place with a set of narrow distributed dextran standards and peak position technique. Adapted columns systems and dissolving processes enable for the adequate separation of carbohydrate polymers. Plant-extracted fructan (a homopolymer with low molar mass and excellent water solubility) and mucilage (differently structured, high molar mass heteropolysaccarides that include existing supramolecular structures, and require a long dissolving time) are presented as examples of the versatility of this technique. Since narrow standards similar to the samples (chemically and structurally) are often unavailable, it must be noted that the obtained molar mass values and distributions by this method are only apparent (relative) values, expressed as dextran equivalents.

Electrosprayable Levan-Coated Nanoclusters and Ultrasound-Responsive Drug Delivery for Cancer Therapy.

In this study, we synthesized levan shell hydrophobic silica nanoclusters encapsulating doxorubicin (L-HSi-Dox) and evaluated their potential as ultrasound-responsive drug delivery systems for cancer treatment. L-HSi-Dox nanoclusters were successfully fabricated by integrating a hydrophobic silica nanoparticle-doxorubicin complex as the core and an amphiphilic levan carbohydrate polymer as the shell by using an electrospray technique. Characterization analyses confirmed the stability, size, and composition of the nanoclusters. In particular, the nanoclusters exhibited a controlled release of Dox under aqueous conditions, demonstrating their potential as efficient drug carriers. The levanic groups of the nanoclusters enhanced the targeted delivery of Dox to specific cancer cells. Furthermore, the synergism between the nanoclusters and ultrasound effectively reduced cell viability and induced cell death, particularly in the GLUT5-overexpressing MDA-MB-231 cells. In a tumor xenograft mouse model, treatment with the nanoclusters and ultrasound significantly reduced the tumor volume and weight without affecting the body weight. Collectively, these results highlight the potential of the L-HSi-Dox nanoclusters and ultrasound as promising drug delivery systems with an enhanced therapeutic efficacy for biomedical applications.

Isolation and characterization of exopolysaccharides from kombucha samples of different origins.

Kombucha is prepared by fermenting sugared green or black tea with a symbiotic culture of bacteria and yeast (SCOBY). Some of the bacteria within the SCOBY are known to form exopolysaccharides (EPS) from sucrose. However, it is yet unknown whether water-soluble EPS are formed in kombucha, and if so, which specific EPS are present. Therefore, different kombucha samples were prepared by fermentation of green and black tea with SCOBYs from different manufacturers. Subsequently, the EPS were isolated and characterized by using various chromatographic methods, partial enzymatic hydrolyses and NMR spectroscopy. It was demonstrated that levans with a varying degree of branching at position O1 (4.3-7.9 %) are present, while only trace amounts of glucans were detected. Furthermore, levans isolated from kombucha had a comparably low molecular weight and the content of levan within the kombucha samples varied from 33 to 562 mg levan/L kombucha. Therefore, our study demonstrated that levans are the main EPS type in kombucha and that levan amounts and structures varied when different starter cultures and ingredients were used. Furthermore, we provide a comprehensive data set on the structural variability of levans from kombucha.

Production, modification and degradation of fructans and fructooligosacharides by enzymes originated from plants.

Non-starch polysaccharides exhibit numerous beneficial health effects but compounds belonging to FODMAP (Fermentable Oligo- Di- and Monosaccharides and Polyols) has been recently connected to several gastrointestinal disorders. This review presents integrated literature data on the occurrence and types of fructans and fructooligosaccharids (classified as FODMAPs) as well as their degrading enzymes present in plants. Plants from the family Asteraceae and many monocotyledones, including families Poaceae and Liliaceae, are the most abundant sources of both fructans and fructan-degrading enzymes. So far, vast majority of publications concerning the application of these specific plants in production of bakery products is related to increase of dietary fibre content in these products. However, there is limited research on their effect on FODMAP content and fibre balance. The authors emphasize the possibility of application of enzyme rich plant extract in food production casting light on the new scientific approach to fibre modification.

Sustainable production of heavy metal-binding levan by a subarctic permafrost thaw lake Pseudomonas strain 2ASCA.

Pseudomonas strain 2ASCA isolated in subarctic Québec, Canada, produced a cell membrane bound levan-type exopolymer (yield 1.17 g/L), after incubation in growth media containing 6 % sucrose (w/v) at temperature of 15 °C for 96 h. The objective of this study was to optimize levan production by varying the growth parameters. Moreover, the polymer's chemical characterization has been studied with the aim of increasing knowledge and leading to future applications in many fields, including heavy metal remediation. Higher levan yields (7.37 g/L) were reached by setting up microbial fermentation conditions based on the re-use of the molasses obtained from sugar beet processing. Spectroscopy analyses confirmed the levan-type nature of the exopolymer released by strain 2ASCA, consisting of a ß-(2,6)-linked fructose repeating unit. Gel permeation chromatography revealed that the polymer has a molecular weight of 13 MDa. Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) showed that the levan sequestered with a strong affinity Cr(III), which has never been previously reported, highlighting an interesting biosorption potential. In addition, SEM analysis revealed the formation of nanoparticles in acidified water solution.

Levan Production by Suhomyces kilbournensis Using Sugarcane Molasses as a Carbon Source in Submerged Fermentation.

The valorization of byproducts from the sugarcane industry represents a potential alternative method with a low energy cost for the production of metabolites that are of commercial and industrial interest. The production of exopolysaccharides (EPSs) was carried out using the yeast Suhomyces kilbournensis isolated from agro-industrial sugarcane, and the products and byproducts of this agro-industrial sugarcane were used as carbon sources for their recovery. The effect of pH, temperature, and carbon and nitrogen sources and their concentration in EPS production by submerged fermentation (SmF) was studied in 170 mL glass containers of uniform geometry at 30 °C with an initial pH of 6.5. The resulting EPSs were characterized with Fourier-transform infrared spectroscopy (FT-IR). The results showed that the highest EPS production yields were 4.26 and 44.33 g/L after 6 h of fermentation using sucrose and molasses as carbon sources, respectively. Finally, an FT-IR analysis of the EPSs produced by S. kilbournensis corresponded to levan, corroborating its origin. It is important to mention that this is the first work that reports the production of levan using this yeast. This is relevant because, currently, most studies are focused on the use of recombinant and genetically modified microorganisms; in this scenario, Suhomyces kilbournensis is a native yeast isolated from the sugar production process, giving it a great advantage in the incorporation of carbon sources into their metabolic processes in order to produce levan sucrose, which uses fructose to polymerize levan.

Investigating the cryoprotective efficacy of fructans in mammalian cell systems via a structure-functional perspective.

Fructans have long been known with their role in protecting organisms against various stress factors due to their ability to induce controlled dehydration and support membrane stability. Considering the vital importance of such features in cryo-technologies, this study aimed to explore the cryoprotective efficacy of fructans in mammalian cell systems where structurally different fructan polymers were examined on in vitro cell models derived from organs such as the liver, frequently used in transplantation, osteoblast, and cord cells, commonly employed in cell banking, as well as human seminal fluids that are of vital importance in assisted reproductive technology. To gain insights into the fructan/membrane interplay, structural differences were linked to rheological properties as well as to lipid membrane interactions where both fluorescein leakage from unilamellar liposomes and membrane integrity of osteoblast cells were monitored. High survival rates obtained with human endothelial, osteoblast and liver cells for up to two months clearly showed that fructans could be considered as effective non-permeating cryoprotectants, especially for extended periods of cryopreservation. In trials with human seminal fluid, short chained levan in combination with human serum albumin and glycerol proved very effective in preserving semen samples across multiple patients without any morphological abnormalities.

Structural characterization of an inulin neoseries-type fructan from Ophiopogonis Radix and the therapeutic effect on liver fibrosis in vivo.

Ophiopogonis Radix is a well-known Traditional Chinese Medicine and functional food that is rich in polysaccharides and has fructan as a characteristic component. In this study, an inulin neoseries-type fructan designated as OJP-W2 was obtained and characterized from Ophiopogonis Radix, and its potential therapeutic effect on liver fibrosis in vivo were investigated. Structural studies revealed that OJP-W2 had a molecular weight of 5.76 kDa and was composed of glucose and fructose with a molar ratio of 1.00:30.87. Further analysis revealed OJP-W2 has a predominantly lineal (1-2)-linked ß-D-fructosyl units linked to the glucose moiety of the sucrose molecule with (2-6)-linked ß-D-fructosyl side chains. Pharmacological studies revealed that OJP-W2 exerted a marked hepatoprotective effect against liver fibrosis, the mechanism of action was involved in regulating collagen deposition (α-SMA, COL1A1 and liver Hyp contents) and TGF-ß/Smads signaling pathway, alleviating liver inflammation (IL-1ß, IL-6, CCL5 and F4/80) and MAPK signaling pathway, and inhibiting hepatic apoptosis (Bax, Bcl-2, ATF4 and Caspase 3). These data provide evidence for expanding Ophiopogonis Radix-acquired fructan types and advancing our understanding of the specific role of inulin neoseries-type fructan in liver fibrosis therapy.

The agavins (Agave carbohydrates) story.

Fructans, are carbohydrates defined as fructose-based polymers with countable degree of polymerization (DP) ranging so far from DP3 to DP60. There are different types of fructans depending on their molecular arrangement. They are categorized as linear inulins and levans, neoseries of inulin and levan, branched graminans, and highly branched neofructans, so called agavins (Agave carbohydrates). It is worth to note that agavins are the most recently described type of fructans and they are also the most complex ones. The complexity of these carbohydrates is correlated to their various isomers and degree of polymerization range, which is correlated to their multifunctional application in industry and human health. Here, we narrate the story of the agavins' discovery. This included their chemical characterization, their benefits, biotechnological applications, and drawbacks over human health. Finally, a perspective of the study of agavins and their interactions with other metabolites through metabolomics is proposed.

Identification of carbohydrate in Polygonatum kingianum Coll. et Hemsl and inhibiting oxidative stress.

The specific structure of Polygonatum kingianum Coll. et Hemsl polysaccharide (PKP) has been rarely reported. In this study, an inulin-type fructan PKP-1, was extracted and purified from Polygonatum kingianum Coll. et Hemsl, and its structural characteristics and antioxidants activity were evaluated. The molecular weights of PKP-1 was determined to be 4.802 kDa. Monosaccharide composition analysis evidenced that PKP-1 was composed of galactose, glucose and fructose in a molar ratio of 0.8 %:7.2 %:92.0 %. Glycosidic linkage and Nuclear Magnetic Resonance (NMR) analysis revealed that PKP-1 exhibited a primary sugar residue linkage of →1-ß-d-Fruf-2→2,6-ß-d-Fruf-1→, where ß-d-Fruf-2→ acts as the side chain and links to the C-6 position of →2,6-ß-d-Fruf-1→. In vitro antioxidant activity assays demonstrated that PKP-1 enhanced the mitigation of hepatic oxidative stress in HepG2 cells induced by free fatty acids. This effect was marked by increased enzymatic activities of superoxidase dismutase (SOD) and catalase (CAT), along with elevated glutathione (GSH) levels. These findings indicate that PKP-1 could be used as a potential natural antioxidant.

An inulin-type fructan CP-A from Codonopsis pilosula alleviates TNBS-induced ulcerative colitis based on serum-untargeted metabolomics.

Ulcerative colitis (UC) is an inflammatory disease with abdominal pain, diarrhea, and bloody stool as the main symptoms. Several studies have confirmed that polysaccharides are effective against UC. It is commonly accepted that the traditional benefits of Radix Codonopsis can be attributed to its polysaccharide contents, and inulin-type fructan CP-A is the main active monomer in the polysaccharide components. Herein, we established a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced UC rat model and lipopolysaccharide (LPS)-induced colonic epithelial cell model (NCM460) to investigate the effect of CP-A on UC. Untargeted metabolomics studies were conducted to identify differential metabolites using ultra-high performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UHPLC-Q-TOF/MS) and enrich metabolic pathways in rat serum. The in vivo assays demonstrated that CP-A reduces colonic macroscopic injury, disease activity index (DAI), histopathological score, interleukin (IL)-8, and tumor necrosis factor-α (TNF-α) levels, as well as the expression of intercellular adhesion molecules. On the other hand, CP-A increases IL-10 and transforming growth factor-ß (TGF-ß) levels. The in vitro experiments indicated that CP-A treatment could reduce nitric oxide (NO) and IL-1ß after LPS stimulation. The metabolomics results suggested that CP-A therapy for UC may be related to the mammalian target of rapamycin (mTOR) signaling pathway. The in vitro and in vivo validation of the pathway showed similar results, indicating that CP-A alleviates UC by preventing the activation of mTOR/p70S6K signaling pathway. These findings offer a fresh approach to treating UC and a theoretical foundation for the future advancement of CP-A.NEW & NOTEWORTHY We report that an inulin-type fructan from Codonopsis pilosula CP-A exhibits a therapeutic effect on experimental colitis. Its mechanism may be to alleviate intestinal inflammation by preventing the activation of mammalian target of rapamycin (mTOR)/p70S6K signaling pathway. These findings offer a fresh approach to treating ulcerative colitis (UC) and a theoretical foundation for the future advancement of CP-A.

Optimized acid hydrolysis conditions for better characterization the structure of inulin-type fructan from Polygonatum sibiricum.

Polygonatum sibiricum is an edible plant species in China known for its abundant polysaccharides. However, correlations between its analytical methods and fine structure have not been established. This is usually due to incomplete cleavage of the glycosidic linkages and instability of hydrolysis. In this study, a new optimal acid hydrolysis method for monosaccharide composition (2 M H2SO4 for 1 h) and methylation analysis (2 mol TFA hydrolysis at 100 °C for 1 h) was developed for characterization of inulin-type fructans, resulting in significantly improved monosaccharide recovery and providing more reliable methylation data. The effectiveness of this method was demonstrated through its application to the study of polysaccharide from P. sibiricum (IPS-70S). The results showed that IPS-70S with a molecular weight of 3.6 kDa is an inulin-type fructans consisting of fructose and glucose in a molar ratio of 27:1. Methylation and NMR analysis indicated that IPS-70S contains →2)-Fruf-(6 â†’ or →2)-Fruf-(1 â†’ with branching →1,6)-Fruf-(2 â†’ and terminates in Glcp-(1 â†’ or Fruf-(2→. In conclusion, optimal acid hydrolysis applicable to the specific polysaccharides contribute to its structurally characterized. The newly optimized acid hydrolysis method for monosaccharide composition and methylation analysis offers a reliable and effective approach to the structural characterization of inulin-type fructans from P. sibiricum. Providing reliable basis for the overall work of NMR analysis and structural analysis, which have potential significance in the field of polysaccharides structural characterization.

Unraveling the role of flexible coil near calcium binding site of levansucrase on thermostability and product profile via proline substitution and molecular dynamics simulations.

Due to its bioactivity and versatile applications, levan has appeared as a promising biomaterial. Levansucrase is responsible for the conversion of sucrose into levan. With the goal of enhancing levan production, the strategy for enhancing the stability of levansucrase is being intensively studied. To make proteins more stable under high temperatures, proline, the most rigid residue, can be introduced into previously flexible regions. Herein, G249, D250, N251, and H252 on the flexible coil close to the calcium binding site of Bacillus licheniformis levansucrase were replaced with proline. Mutations at G249P greatly enhance both the enzyme's thermodynamic and kinetic stability, while those at H252P improve solely the enzyme's kinetic stability. GPC analysis revealed that G249P synthesize more levan, but H252P generate primarily oligosaccharides. Molecular dynamics simulations (MD) and MM/GBSA analysis revealed that G249P mutation increased not only the stability of levansucrase, but also affinity toward fructan.

Fructose-Containing Plant Carbohydrates: Biological Activities and Medical Applications.

The review considers the chemical structure specifics and distribution in plants for fructose-containing carbohydrates (fructans). Various biological activities were observed in fructans and associated with their physicochemical features. Fructans affect many physiological and biochemical processes in the human body, improving health and reducing the risk of various disorders. Prebiotic activity is the most important physiological function of fructans. Fructans improve the microflora composition in the colon and intestinal mucosa by increasing the content of useful bacteria and decreasing the content of potentially harmful microorganisms, stimulate the physiological functions of the microflora, and provide for a better state of the intestine and a better health status. By modifying the intestinal microbiota and utilizing certain additional mechanisms, fructans can favorably affect the immune function, decrease the risk of various inflammatory processes, and to reduce the likelihood of tumorigenesis due to exposure to carcinogens. Fructans improve carbohydrate and lipid metabolism by reducing the blood levels of glucose, total cholesterol, low-density lipoprotein (LDL), and very-low-density lipoprotein (VLDL) and increasing the blood content of high-density lipoprotein (HLD). Fructans are low in calories, and their use in foods reduces the risk of obesity. Fructans facilitate higher calcium absorption and increase the bone density, thus reducing the risk of osteoporosis. Fructants protect the body from oxidative stress, intestinal infections, and parasitic invasions.

Glycoside hydrolase family 32 enzymes from Bombella spp. catalyze the formation of high-molecular weight fructans from sucrose.

AIMS: Acetic acid bacteria of the genus Bombella have not been reported to produce exopolysaccharides (EPS). In this study, the formation of fructans by B. apis TMW 2.1884 and B. mellum TMW 2.1889 was investigated. METHODS AND RESULTS: Out of eight strains from four different Bombella species, only B. apis TMW 2.1884 and B. mellum TMW 2.1889 showed EPS formation with 50 g l-1 sucrose as substrate. Both EPS were identified as high-molecular weight (HMW) polymers (106-107 Da) by asymmetric flow field-flow fractionation coupled to multi angle laser light scattering and UV detecors (AF4-MALLS/UV) and high performance size exclusion chromatography coupled to MALLS and refractive index detectors (HPSEC-MALLS/RI) analyses. Monosaccharide analysis via trifluoroacetic acid hydrolysis showed that both EPS are fructans. Determination of glycosidic linkages by methylation analysis revealed mainly 2,6-linked fructofuranose (Fruf) units with additional 2,1-linked Fruf units (10%) and 2,1,6-Fruf branched units (7%). No glycoside hydrolase (GH) 68 family genes that are typically associated with the formation of HMW fructans in bacteria could be identified in the genomes. Through heterologous expression in Escherichia coli Top10, an enzyme of the GH32 family could be assigned to the catalysis of fructan formation. The identified fructosyltransferases could be clearly differentiated phylogenetically and structurally from other previously described bacterial fructosyltransferases. CONCLUSIONS: The formation of HMW fructans by individual strains of the genus Bombella is catalyzed by enzymes of the GH32 family. Analysis of the fructans revealed an atypical structure consisting of 2,6-linked Fruf units as well as 2,1-linked Fruf units and 2,1,6-Fruf units.

Similarities and differences of nano-sized levan synthesized by Bacillus haynesii at low and high temperatures: Characterization and bioactivity.

Levan is a biopolymer with many different uses. Temperature is an important parameter in biopolymer synthesis. Herein, levan production was carried out from Bacillus haynesii, a thermophilic microorganism, in the temperature range of 4 °C-95 °C. The highest levan production was measured as 10.9 g/L at 37 °C. The synthesized samples were characterized by FTIR and NMR analysis. The particle size of the levan samples varied between 153 and 824.4 nm at different temperatures. In levan samples produced at high temperatures, the water absorption capacity is higher in accordance with the particle size. Irregularities were observed in the surface pores at temperatures of 60 °C and above. The highest emulsion capacity of 83.4 % was measured in the sample synthesized at 4 °C. The antioxidant activity of all levan samples synthesized at different temperatures was measured as 84 % on average. All synthesized levan samples showed antibacterial effect on pathogenic bacteria. In addition, levan synthesized at 45 °C showed the highest antimicrobial effect on E. coli ATCC 35218 with an inhibition zone of 21.3 ± 1.82 mm. Antimicrobial activity against yeast sample C. albicans, was measured only in levan samples synthesized at 80 °C, 90 °C, 95 °C temperatures. Levan synthesized from Bacillus haynesii at low and high temperatures showed differences in characterization and bioactivity.