İlgi alanları

• MakaleYalnız künye2026/r/bayburt/12808
  Development and characterization of postbiotic-enriched biodegradable films with antifungal activity for tomato storage

  Kaya, Yasemin; İspirli, Hümeyra; Bozkurt, Fatih; Sağdıç, Osman; Şengül, Mustafa; Dertli, Enes

  BACKGROUND: One of the major contributors to postharvest losses in tomatoes is the development of infectious mold diseases. In this study, four distinct biodegradable film formulations were developed incorporating postbiotics derived from Lactiplantibacillus plantarum Y48 and the polysaccharide alternan. The formulations included alternan, sodium alginate and glycerol (AAG), alternan, postbiotic, sodium alginate and glycerol (APAG), postbiotic, sodium alginate and glycerol (PAG), and sodium alginate and glycerol (AG) as a control. The films were characterized in terms of their physical, mechanical, thermal, and morphological properties. To assess antifungal efficacy, tomatoes artificially inoculated with Alternaria alternata were coated with each film and stored at ambient temperature for 8 days. RESULTS: The incorporation of alternan and postbiotics enhanced both the mechanical strength and thermal stability of the films. Fourier-transform infrared (FTIR) analysis confirmed the successful integration of the bioactive components into the polymer matrix. Scanning electron microscopy (SEM) imaging revealed that postbiotic addition contributed to a rougher and more rigid surface morphology, while alternan improved the structural cohesion of the films. All film formulations exhibited significant inhibitory effects against A. alternata, with the PAG formulation demonstrating the most pronounced antifungal activity. CONCLUSION: These results suggest that the PAG film, enriched with postbiotics, represents a promising biocontrol strategy for mitigating fungal spoilage in tomatoes. In conclusion, this study underscores the potential of combining postbiotics and alternan for the development of active, biodegradable edible films with antifungal functionality for postharvest preservation.

  AtıfScopus2·WoS2

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• MakaleYalnız künye2026/r/bayburt/12780
  Tailoring Physicochemical and Technological Properties of α-Glucans Through Mutations of GTFA from Lactobacillus Reuteri E81

  Gökcan, Hande; İspirli, Hümeyra; Dertli, Enes

  Glucansucrases catalyze the production of α-glucans using sucrose as substrate with distinct physicochemical characteristics originates from mainly the type of linkages, degree of branching and molecular mass. New forms of α-glucans can be produced by applying specific mutations to glucansucrases. In this study, a single and double mutation at Leu933 and Leu935 sites of glucansucrase E81 was applied and L933I and L933I-L935F sites modified glucansucrase was obtained. Structural characterisation of bioengineered α-glucans revealed that ratio of (1 → 3):(1 → 6) linked α-Glc units altered at L933I whereas no (1 → 3)-linked α-Glc units were presented for L933I-L935F modified glucansucrase detected by NMR analysis. Both bioengineered α-glucans had lower molecular weights in comparison to glucan E81 detected by GPC analysis. TGA and DSC analysis were applied to detect the thermal profiles of bioengineered α-glucans whereas FTIR and XRD analysis were applied to determine the alterations in the structural and physical nature of the bioengineered α-glucans, respectively. Finally, SEM and AFM analysis were applied to explore the morphological modifications of the bioengineered α-glucans. This study provides a better understanding for the potential role of final glucan structures on their physicochemical characteristics. Keywords: glucansucrase; carbohydrate engineering; mutation.

  AtıfScopus2·WoS2

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• Derleme MakaleYayıncıda açık erişim2026/r/bayburt/12719
  Functional and Technological Roles of Limosilactobacillus reuteri and Its Critical Metabolites in Food Systems

  Yildirim, Sema Nur; İspirli, Hümeyra; Dertli, Enes

  Limosilactobacillus reuteri is a lactic acid bacteria (LAB) recognized for its significant technological and functional properties. This species produces diverse metabolites, including reuterin, exopolysaccharides (EPSs), B-group vitamins, short-chain fatty acids (SCFAs), and bioactive peptides, which benefit food systems and host health. However, high strain-specificity and metabolite complexity present challenges in elucidating precise mechanisms of action of these metabolites for their functional and technological roles. This review provides a comprehensive perspective on the latest applications of Lmb. reuteri and its metabolites in food technology by focusing on its utilization in diverse matrices, including dairy, plant-based products, supplements, and edible packaging systems, where it serves to extend shelf life, enhance nutritional profiles, and improve sensory attributes. The strain-specific nature of Lmb. reuteri allows for tailored applications to meet technological requirements. As consumer demand for clean-label and health-promoting foods increases, Lmb. reuteri stands out as a critical LAB species, for the development of next-generation functional foods and preservation strategies. Understanding the potential roles of this species in human and animal health and food safety will help us to build a roadmap for future research and industrial implementation.

  AtıfScopus1·WoS1

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• MakaleYayıncıda açık erişim2026/r/bayburt/11462
  Characterization of Highly Branched Dextran VB113 Produced by Leuconostoc mesenteroides VB113 as Traditional Pickle Isolate

  İspirli, Hümeyra; Kavak, Akif Emre; Dertli, Enes

  Lactic Acid Bacteria (LAB) from traditional fermented foods serve as a promising source of novel exopolysaccharides (EPSs) with desirable techno-functional properties. In this study, the EPS production ability of LAB strains from traditional pickles was tested and a strong slimy isolate grown in a sucrose-rich environment was further selected. The isolate was identified as Leuconostoc mesenteroides VB113 and its EPS production characteristics were determined. HPLC analysis revealed that glucose was the only monomer in the EPS repeating structure, whereas 1H and 13C NMR spectroscopy analysis demonstrated a branched dextran structure with 20% (1 → 3)-linked α-D-glucose units. Dextran VB113 showed a molecular weight of 2.4 × 106 Da tested by GPC analysis. The functional groups within dextran VB113 were determined by FTIR analysis, and XRD analysis demonstrated its amorphous physical status. TGA and DSC analysis were applied for thermal characterization and a degradation temperature of 272.25 °C was observed for dextran VB113, suggesting its high thermal resistance. The micro-structural features of dextran VB113 were tested by SEM and AFM analysis that revealed spherical and fibrillary properties, respectively. These findings revealed the importance of testing different niches to obtain novel EPS-producing LAB strains that can be further evaluated to enhance the techno-functional properties of food systems. The branched nature of dextran VB113, together with its molecular weight and thermal characteristics, offers practical advantages for its potential usage as a thermal-stable thickening agent, emulsion stabilizer, and fat replacer in high-temperature food processing applications, such as bakery products, processed dairy, and plant-based meat analogs.

  AtıfScopus1·WoS1

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• MakaleYalnız künye2026/r/bayburt/11109
  Structural and physicochemical characterisation of branched dextrans produced by an active α-(1→2) branching sucrase from Apilactobacillus kunkeei PDER37

  İspirli, Hümeyra; Dertli, Enes

  Recently, branching sucrases encoded in the genomes of certain Lactic Acid Bacteria (LAB) strains have become novel enzymes to obtain branched α-glucans. In this study an active α-(1 → 2) branching sucrase from Apilactobacillus kunkeei PDER37 was expressed, characterised and distinct branched dextrans was obtained with reactions under different sucrose: dextran ratio. Structural characterisation by 1H and 13C NMR analysis demonstrated the branching of the dextran with (1 → 2)-linked α- d -glucose units with no alteration in the final structure depending on sucrose: dextran ratio (D0) but this ratio was effective for the determination of the molecular weights of the branched dextrans (D1, D2 and D3). FTIR analysis further supported the dextran structures and suggested the higher accumulation of the α-Glc units in the branched dextrans. Thermal characterisation of the branched dextrans obtained by TGA and DSC analysis suggested the increased hygroscopicity of the branching units. Both SEM and AFM analysis demonstrated more porous chain like structures in the branched dextrans. This study provides valuable information on the role of active α-(1 → 2) branching sucrase (BS37) for the production of branched dextrans with potential increased physicochemical status applicable for food and other industries.

  İncele
• MakaleYayıncıda açık erişim2025Scopus SJRQ1/r/bayburt/10808
  Characterizations and In Vitro Gut Microbiome Modulatory Effects of Gluco-Oligosaccharides Synthesized by the Acceptor Reactions of Glucansucrase 53

  Bayaman, Rabia Yusra; Alkay, Zuhal; Ispirli, Humeyra; Arioglu-Tuncil, Seda; Dere, Sevda; Can, Hasan; Gonzales, Miguel Angel Alvarez; Sagdic, Osman; Lindemann, Stephen R.; Tuncil, Yunus Emre

  The production of novel oligosaccharides with potential prebiotic effects is of interest to expand the current market and explore the effectiveness of new functional carbohydrate forms. The utilization of glucansucrases is a cost-effective and environmentally friendly biotechnological strategy for producing novel gluco-oligosaccharides through acceptor reactions. In this study, an active glucansucrase (GS53) was used to produce gluco-oligosaccharides via its acceptor reactions with glucose, maltose, and maltotriose, and these oligosaccharides were tested in terms of structure and their gut microbiome modulatory effects. The formations of oligosaccharides were monitored by TLC analysis, and GS53 was active for the three acceptors but not for the other sugars tested. The structural characterization of the gluco-oligosaccharides by 1H NMR analysis revealed the glycosylation of each acceptor with alpha-(1 -> 3) and alpha-(1 -> 6) linkages, whereas LC-MS analysis demonstrated the formations of DP 8, DP 7, and DP 6 oligosaccharides with acceptors maltose, maltotriose, and glucose, respectively. In vitro fecal fermentation analysis, in which microbial short-chain fatty acids (SCFAs) and microbial compositional changes were assessed using gas chromatography and 16S rRNA sequencing, respectively, demonstrated that the gluco-oligosaccharides formed SCFAs-particularly propionate and butyrate-at levels comparable to those observed with inulin, a well-established prebiotic. Additionally, the gluco-oligosaccharides were found to promote the growth of Bifidobacterium adolescentis and Blautia OTUs, which are known to have important physiological functions beneficial to human health. Overall, these results demonstrate that gluco-oligosaccharides synthesized using GS53 through acceptor reactions exhibit prebiotic potentials and could be utilized in the future as dietary supplements as well as in the development of functional foods targeting colonic health.

  AtıfScopus3·WoS3

  İncele
• MakaleYalnız künye2025/r/bayburt/12789
  Characterization and in situ bioprotective efficacy of reuterin E81 produced by Limosilactobacillus reuteri E81 in white cheese model

  İspirli, Hümeyra; Öztürk, Hale İnci; Dertli, Enes

  This study focused on characterization and in situ application of reuterin E81, a potent antimicrobial compound produced by Limosilactobacillus (L.) reuteri E81, in white cheese. Strain E81 harbored the gene island containing pdu-cbi-cob-hem clusters responsible for reuterin production and this led to investigation of reuterin production for this strain. Initially, reuterin was synthesized from glycerol and characterized using NMR and FT-MIR analyses. Specific 1H and 13C NMR peaks confirmed the presence of reuterin components such as 3-hydroxypropionaldehyde and acrolein, while FT-MIR spectra indicated a distinct carbonyl (C=O) stretching band at 1717 cm−1, characteristic of aldehyde groups of reuterin system. Reuterin E81 showed dose dependent fungistatic and bactericidal effects, with complete inhibition of Gram-negative ones at lower doses. In white cheese production, four groups were prepared, including control and experimental groups with or without glycerol addition. The challenge test conducted over 30 days of cold storage demonstrated that white cheese samples containing L. reuteri E81 and glycerol achieved a significant reduction in microbial loads, with Escherichia (E.) coli counts decreasing from 6.4 log CFU/g to undetectable levels, which was attributed to in situ reuterin production. Meanwhile, total aerobic mesophilic bacterial counts declined progressively. These findings highlight the potential of in situ reuterin production as a natural strategy to enhance the microbiological safety of white cheese. However, it also inhibited the growth of S. thermophilus and L. reuteri cultures. The inhibitory effects of reuterin on beneficial lactic acid bacteria suggest the need for further optimization to balance food safety with starter culture viability.

  AtıfScopus5·WoS5

  İncele
• MakaleYalnız künye2025/r/bayburt/11454
  Physicochemical characterization of glucan AK7 produced by quinoa sourdough isolate Leuconostoc mesenteroides AK7

  İspirli, Hümeyra; Arslan, Şeyma; Tuncer, Fatma; Kasapoglu, Muhammed Z.; Ortakcı, Fatih; Tuncil, Yunus Emre; Dertli, Enes

  The production of exopolysaccharides (EPS) by Lactic Acid Bacteria (LAB) is technologically crucial because it has a wide range of applications in food technology, biotechnology, and health. In the present work, a new quinoa sourdough isolate of Leuconostoc mesenteroides strain AK7 was identified as a novel producer of a dextran-type EPS. The monomeric units of EPS AK7 were confirmed by HPLC analysis, while NMR spectroscopy and GC–MS linkage analysis further verified the EPS structure as a branched dextran containing mainly (1 → 6)-linked α- D -glucose units with (1 → 3,6)-linked α- D -glucose unit as branching points. An average molecular weight of 1.2 × 106 Da was detected for glucan AK7. FTIR analysis was applied to determine the functional units of dextran AK7. In terms of thermal features, TGA and DSC analysis were applied and a specific degradation temperature of 300 °C was found for dextran AK7. The morphology of the lyophilized EPS displayed a rough, dense, and porous structure, as observed through SEM analysis. Dextran AK7 revealed a semi-crystalline nature detected by XRD analysis. These structural and functional properties of dextran AK7 produced by Leuconostoc mesenteroides AK7 from quinoa sourdough suggest its potential usage for food industry applications.

  AtıfScopus3·WoS3

  İncele
• MakaleYalnız künye2025/r/bayburt/11386
  Biosynthesis of alternan-stabilized selenium nanoparticles: A study on characterization and applications for antibacterial and antifungal purposes

  ElObeid, Tahra; Yilmaz, Mustafa Tahsin; Ispirli, Humeyra; Sagdic, Osman; Taylan, Osman; Basahel, Abdulrahman; Karaboga, Dervis; Durak, Muhammed Zeki; Dertli, Enes

  In this study, the alternan/selenium nanoparticles (Alt/SeNPs) were characterized with respect to their formation, morphology, size, selenium distribution, molecular, crystallographic, and thermal properties using UV–Vis spectroscopy, SEM, TEM, EDAX, FTIR, XRD, DSC and TGA measurements. UV–VIS measurements confirmed the synthesis of nanoparticles by observing a maximum surface plasmon resonance peak at 212 nm. In this study, alternan contributed to stabilizing the dispersion of SeNPs, resulting in a cluster of spherical and well-dispersed nanoparticles ranging in size from 50 to 90 nanometers. Nanoparticles were found to be highly thermally stable and in a nanocrystalline structure. The ABTS and CUPRAC radical scavenging activities of Alt/SeNPs were remarkable (95% and 78% at 4 and 6 mg/mL levels of Alt/SeNPs, respectively). Alt/SeNPs had also good inhibitory activities (3.5–4.0 and 4–15 mm of inhibition zone levels at 5 mg/mL level of Alt/against foodborne pathogenic bacteria and fungi, respectively).

  AtıfScopus1·WoS2

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• MakaleYalnız künye2025/r/bayburt/11233
  Liquorilactobacillus hordei SK6 and Liquorilactobacillus mali SK26 from Traditional Water Kefir Produce Dextrans with Technological Roles

  Edis, Kader Korkmaz; İspirli, Hümeyra; Yilmaz, Mustafa Tahsin; Dertli, Enes

  The significance of exopolysaccharides (EPS) in various applications has garnered increasing attention. In this study, two bacteria, Liquorilactobacillus hordei SK6 and Liquorilactobacillus mali SK26, isolated from traditional water kefir grains, produced 8.89 g/L and 7.2 g/L of homopolymeric glucan, respectively. NMR analysis revealed that both glucans were dextrans composed of (1 → 6)-linked α-d-glucose units, with (1 → 3)-linked α-d-glucose units serving as branching points, accounting for 5.3 ± 0.2% in dextran SK6 and 2.7 ± 0.15% in SK26. FTIR and XRD analyses further confirmed the amorphous nature of the dextrans, although dextran SK6 exhibited micro-arranged structures. Thermal characterization using TGA and DSC showed degradation temperatures of 298.5 °C for dextran SK6 and 282.1 °C for dextran SK26. Clear differences in morphological properties were observed using AFM and SEM. These findings provide valuable insights into dextran-producing strains and their potential applications in various industries.

  AtıfScopus3·WoS2

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