Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2026Scopus SJRQ1Development 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.
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İncele - MakaleAçık Erişim2026Scopus SJRQ2Tailoring 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.
AtıfScopus2WoS2OpenAlex2İncele - Derleme MakaleAçık Erişim2026Scopus SJRQ1Functional 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.
AtıfScopus1WoS1OpenAlex2İncele - MakaleAçık Erişim2026Scopus SJRQ1Characterization 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.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2026Scopus SJRQ1Structural 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.
- MakaleYalnız künye2025Scopus SJRQ1Characterization 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.
AtıfScopus5WoS5OpenAlex6İncele - MakaleAçık Erişim2025Scopus SJRQ1Physicochemical 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.
AtıfScopus3WoS3OpenAlex3İncele - MakaleAçık Erişim2025Scopus SJRQ2Liquorilactobacillus 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.
AtıfScopus3WoS2OpenAlex4İncele - MakaleAçık Erişim2025Scopus SJRQ1Characterization and immune-modulatory roles of branched glucan and acetylated gluco-oligosaccharides produced by glucansucrase 40 from Leuconostoc mesenteroides YTU 40
Dere, Sevda; İspirli, Hümeyra; Korkmaz, Kader; Tuncil, Yunus Emre; Sagdic, Osman; Narbad, Arjan; Ayyash, Mutamed; Dertli, Enes
Glucansucrases (GS) are functional enzymes for the production of distinct glucan and gluco-oligosaccharide structures with potential bioactive characteristics. In this study, an active glucansucrase (GS40) was identified within the genome of Leuconostoc mesenteroides YTU 40 that was further cloned, heterologously expressed and biochemically characterised. GS40 was capable of production of a branched dextran with ~ 20% (1→3)-α-D-Glc residues detected by1H and13C NMR analysis. Acceptor reactions of GS40 with maltose and cellobiose were performed and distinct maltose/cellobiose derivative acetylated gluco-oligosaccharides were produced detected by TLC, NMR and LC-MS analysis. The bioactive characteristics of branched dextran and gluco-oligosaccharides were tested by determination of their immune-modulatory roles in terms of triggering IL-12, IL-10, IL-4 and TNF-α cytokine levels. These findings can be important to unveil the role of glucansucrases for the production of gluco-oligosaccharides that can be used as functional ingredients for food and other industries.
AtıfScopus3WoS3OpenAlex3İncele - MakaleAçık Erişim2025Scopus SJRQ1The prebiotic potential of alternansucrase-based glucooligosaccharides: the effects on short-chain fatty acids production and microbiome diversity
Ozulku, Gorkem; Harris, Hannah C.; Savva, George M.; Ahn-Jarvis, Jennifer H.; İspirli, Hümeyra; Dertli, Enes; Warren, Frederick J.
Glucooligosaccharides (GLOS) produced by glucansucrases via acceptor reactions are oligosaccharides that transit upper intestinal tract and evade digestion and may be considered to be a prebiotic. The prebiotic function of GLOS can be dictated by the type of acceptor sugar used during its production. Therefore, the prebiotic effect on the gut microbiome and short chain fatty acids (SCFAs) production can be used to inform the selection of acceptor sugars. In this study, alternansucrase-based GLOS derived from different acceptor sugars (melibiose, cellobiose and lactose) and inulin (positive control) were investigated using in vitro colon model fermentation to examine their prebiotic effect and SCFAs production. Microbiome composition was determined using shotgun metagenomics. SCFAs and lactate formation was determined using 1H NMR spectroscopy. Fusicatenibacter saccharivorans and Bacteroides uniformis appeared to increase in abundance after 24 h following fermentation of all three GLOS. The highest abundance for Bifidobacterium longum was seen after supplementation with lactose derived GLOS. Fermentation of GLOS appeared to produce around twice as much acetate than fermentation with inulin, while similar amounts of other SCFAs and lactate were produced. Melibiose derived GLOS supplementation in healthy 3 donors increased F. saccharivorans while inulin supplementation promoted Lactobacillales in order level. This study suggests that there may be beneficial effects of GLOS's on gut microbiome composition and metabolite composition, relative to the effects seen for inulin.
AtıfScopus1OpenAlex1İncele - MakaleAçık Erişim2024Scopus SJRQ1Physicochemical and structural characterisation of a branched dextran type exopolysaccharide (EPS) from Weissella confusa S6 isolated from fermented sausage (Sucuk)
Özpınar, Fatma Beyza; İspirli, Hümeyra; Kayacan, Selma; Korkmaz, Kader; Dere, Sevda; Sagdic, Osman; Alkay, Zuhal; Tunçil, Yunus Emre; Ayyash, Mutamed; Dertli, Enes
Exopolysaccharide (EPS) producing Lactic Acid Bacteria (LAB) species can be presented in distinct environments. In this study, Turkish fermented sausage (sucuk) was tested for the presence of EPS producer LAB strains and slimy-mucoid colonies were selected for further tests. Among the isolates, Weissella confusa strain S6 was identified and tested for the physicochemical characterisation of its EPS. This strain was found to produce 0.74 g L−1 of EPS in modified BHI medium conditions. Structural characterisation of EPS S6 by 1H and 13C NMR demonstrated that EPS S6 was a highly branched dextran type glucan formed by mainly (1 → 2)-linked α-D-glucose units together with low levels of (1 → 3)-linked α-D-glucose units as branching points. This structure was further confirmed by methylation analysis detected by GC–MS. An average molecular weight of 8 × 106 Da was detected for dextran S6. The FTIR analysis supported the dextran structure and revealed the presence of distinct functional groups within dextran S6 structure. A strong thermal profile was observed for dextran S6 detected by DSC and TGA analysis and dextran S6 revealed a degradation temperature of 289 °C. In terms of physical status, dextran S6 showed amorphous nature detected by XRD analysis. SEM analysis of dextran S6 demonstrated its rough, compact and porous morphology whereas AFM analysis of dextran S6 detected in its water solution showed the irregularity with no clear cross-link within the dextran chains. These technological features of dextran S6 suggests its potential to be used for in situ or ex situ application during meat fermentations.
AtıfScopus25WoS24OpenAlex29İncele - MakaleYalnız künye2024Scopus SJRQ2The wound healing effect and DNA damage repair of exopolysaccharide extracted from Weissella cibaria MED17
Kahraman-Ilıkkan, Özge; Akad Dinçer, Selin; Bağdat, Elif Şeyma; Çağlar, Işılsu; Dertli, Enes; İspirli, Hümeyra; Şahin, Feride İffet
Lactic acid bacteria can synthesize exopolysaccharides (EPSs), and some of these EPSs have pharmaceutical or medicinal properties. However, the wound healing capacities of EPSs have rarely been reported. In this study, EPS extracted from Weissella cibaria MED17 was used to investigate wound healing capacity. MED17 EPS was previously characterized and antioxidant capacity was also demonstrated. The application dose of the compound was determined by the MTT assay. The comet assay was applied to reveal the free radical scavenging activity and protection capacity of MED 17 against DNA damage by inducing oxidative stress and DNA damage with Mitomycin-C (MMC) in the cells. The comet assay showed that 15 mg/ml MED 17 EPS could ameliorate DNA damage by 50%. Moreover, the scratch test investigated the wound-healing effect of MED 17 EPS on HT-29 colon cells. MED 17 EPS could stimulate the migration of HT-29 and ameliorate MMC-induced DNA damage. However, further studies need to be conducted to clarify the mechanisms of the wound-healing process of MED 17.
AtıfScopus5WoS5OpenAlex5İncele - MakaleAçık Erişim2023Scopus SJRQ2Characterisation of dextran AP-27 produced by bee pollen isolate Lactobacillus kunkeei AP-27
Yilmaz, Mustafa T.; İspirli, Hümeyra; Alidrisi, Hassan; Taylan, Osman; Dertli, Enes
An exopolysaccharide (EPS) produced by bee pollen isolate Lactobacillus kunkeei AP-27 was characterised in this study. EPS monomeric composition of strain AP-27 was characterised by High-performance liquid chromatography (HPLC) analysis and glucose was the only sugar in the EPS repeating unit. Structural analysis of glucan AP27 by 1H and 13C Nuclear magnetic resonance (NMR) analysis demonstrated that this glucan was a dextran ((1→6)-linked α-D-glucose units as the main body) consisting very low level of (1 → 4)-linked α-D-glucose units (∼ 0.5 %). Dextran AP-27 had a degradation temperature of 308 °C that revealed its superior thermal strength identified by Thermogravimetric (TGA) and Differential scanning calorimetry (DSC) analysis. The molecular weight of dextran AP-27 was determined to be 25 kDa by Gel Permeation Chromatography (GPC) analysis. Crystallographic properties of dextran AP-27 was determined by X-ray diffraction (XRD) analysis that divulged its amorphous feature. Scanning Electron Microscopy (SEM) analysis was applied for microstructural characterisation of dextran AP-27 which revealed its regular sphere like characteristics. These findings suggest that Lactic Acid Bacteria (LAB) strains from different environments such as bee products can be the source for distinct EPS producer strains.
AtıfScopus9WoS8OpenAlex7İncele - MakaleAçık Erişim2023Scopus SJRQ1Physicochemical Characterization of Dextran HE29 Produced by the Leuconostoc citreum HE29 Isolated from Traditional Fermented Pickle
İspirli, Hümeyra
In this study, lactic acid bacteria (LAB) strains were isolated from traditional fermented pickles, and among the identified strains, Leuconostoc citreum HE29 with a strong slimy colony profile was further selected to determine the physicochemical and techno-functional properties of its exopolysaccharide (EPS). Glucose was the only sugar monomer in the core unit of EPS HE29 detected by HPLC analysis, and glucan HE29 revealed 7.3 kDa of molecular weight. Structural characterization of glucan HE29 by 1H and 13C NMR spectroscopy analysis demonstrated that EPS HE29 was a dextran-type EPS containing 5.3% levels of (1 → 3)-linked α-D-glucose units. This structural configuration was also supported by FT-IR analysis, which also demonstrated the functional groups within the dextran HE29 structure. In terms of thermal properties detected by TGA and DSC analysis, dextran HE29 demonstrated a degradation temperature of around 280 °C, showing its strong thermal features. A semi-crystalline nature was observed for dextran HE29 detected by XRD analysis. Finally, AFM and SEM analysis revealed tangled network-like properties and web-like branched structures for dextran HE29, respectively. These findings suggest the importance of plant-based fermented products as LAB sources in obtaining novel EPS structures with potential techno-functional roles.
AtıfScopus10WoS9OpenAlex11İncele - MakaleAçık Erişim2023Scopus SJRQ2Characterization of Bee Bread Produced with Defined Starter Cultures Mimicking the Natural Fermentation Process
Poyraz, Fatmanur; Yalmanci, Dilara; İspirli, Hümeyra; Dertli, Enes
Bee bread is a product with unique properties for humans and bees that is produced through the fermentation of pollen in the honeycomb, mainly caused by lactic acid bacteria (LAB) and yeast strains present in the environment. It is a rich source of nutrients such as proteins, polyphenols and vitamins. Despite the potential nutritional value of bee bread, it is consumed at low levels, as harvesting bee bread from the hives is costly and difficult. This study aimed to produce a standard bee bread by using different strains of the fructophilic lactic acid bacteria (FLAB) Lactobacillus kunkeei and the yeasts Starmeralla magnolia MP-2 and Zygosaccharomyces siamensis MP-14, previously isolated from bee products. In this context, bee bread was produced from pollen by solid-state fermentation using selected FLAB and yeast species, which were then compared with spontaneously developed and commercially available bee bread in terms of microbial stability, physicochemical properties, total phenolic component amounts, in vitro digestibility and amino acid profiles. As a result, it was determined that bee bread made from bee pollen fermented with starter cultures showed improved characteristics than commercial bee bread and was more advantageous in terms of absorption as well as production processes.
AtıfScopus19WoS17OpenAlex18İncele - MakaleAçık Erişim2023Scopus SJRQ1Structural characterization of potato starch modified by a 4,6-α-glucanotransferase B from Lactobacillus reuteri E81
Hassanein, Wael S.; İspirli, Hümeyra; Dertli, Enes; Yilmaz, Mustafa Tahsin
The recent reports have revealed that increase in amount of α-1,6 linkages by modification of potato starch with enzyme (glycosyltransferases) treatment gains slowly digestible properties to the starch; however, the formation of new α-1,6-glycosidic linkages diminish the thermal resistance of the starch granules. In this study, a putative GtfB-E81, (a 4,6-α-glucanotransferase-4,6-αGT) from L. reuteri E81 was firstly used to produce a short length of α-1,6 linkages. NMR results revealed that external short chains mostly comprised of 1–6 glucosyl units were newly produced in potato starch, and the α-1,6 linkage ratio was significantly increased from 2.9 % to 36.8 %, suggesting that this novel GtfB-E81 might have potentially an efficient transferase activity. In our study, native and GtfB-E81 modified starches showed fundamental similarities with respect to their molecular properties and treatment of native potato starch with GtfB-E81 did not remarkably change thermal stability of the potato starch, which seems to be very prominent for the food industry given the significantly decreased thermal stability results obtained for the enzyme modified starches reported in the literature. Therefore, the results of this study should open up emerging perspectives for regulating slowly digestible characteristics of potato starch in future studies without a significant change in the molecular, thermal, and crystallographic properties.
AtıfScopus14WoS14OpenAlex18İncele - MakaleYalnız künye2023Scopus SJRQ1Utilisation of an active branching sucrase from Lactobacillus kunkeei AP-37 to produce techno-functional poly-oligosaccharides
İspirli, Hümeyra; Korkmaz, Kader; Arioglu-Tuncil, Seda; Bozkurt, Fatih; Sağdıç, Osman; Tunçil, Yunus Emre; Narbad, Arjan; Dertli, Enes
Glucansucrase AP-37 was extracted from the culture supernatant of Lactobacillus kunkeei AP-37 and characteristics of the glucan produced by the active glucansucrase in terms of structural and functional roles were determined in this study. A molecular weight around 300 kDa was observed for glucansucrase AP-37 and its acceptor reactions with maltose, melibiose and mannose were also conducted to unveil the prebiotic potential of the poly-oligosaccharides formed via these reactions. The core structure of glucan AP-37 was determined by 1H and 13C NMR and GC/MS analysis which revealed that glucan AP-37 was a highly branched dextran composing of high levels of (1 → 3)-linked α-D-glucose units with low levels of (1 → 2)-linked α-D-glucose units. The structural features of the glucan formed, demonstrated that glucansucrase AP-37 was an α-(1 → 3) branching sucrase. Dextran AP-37 was further characterised by FTIR analysis and XRD analysis demonstrated its amorphous nature. A fibrous compact morphology was observed for dextran AP-37 with SEM analysis whereas TGA and DSC analysis revealed its high stability as no degradation was observed up to 312 °C. Finally, the prebiotic potential of the dextran AP-37 and the gluco-oligosaccharides produced with the acceptor reaction of α-(1 → 3) branching sucrase AP-37 were determined and promising results were found for the gluco-oligosaccharides to act as prebiotics.
AtıfScopus13WoS12OpenAlex13İncele - MakaleAçık Erişim2022Scopus SJRQ3Optimization of lactose derivative hetero-oligosaccharides production using whey as the acceptor molecule by an active glucansucrase
Kabli, Mohammad; İspirli, Hümeyra; Balubaid, Mohammed; Taylan, Osman; Yılmaz, Mustafa Tahsin; Dertli, Enes
Glucansucrases are capable of synthesis of distinct oligosaccharides using different acceptor molecules and in this study lactose derivative hetero-oligosaccharides were shown to be produced by an active glucansucrase in its acceptor reaction with sucrose and whey as the donor-acceptor molecules, respectively. Following the monitoring of the reaction products by TLC analysis, the effects of reaction parameters in terms of enzyme concentration, sucrose/whey ratio and reaction temperature on final oligosaccharide yields (OY) were optimized by Response Surface Methodology (RSM). Results indicated that increment of enzyme concentration and reaction temperature decreased the OY in a particular reaction time whereas the OY increased with the increment of sucrose/whey ratio in the acceptor reactions of glucansucrase E81 with whey as the acceptor molecule. A low level of glucansucrase E81 concentration was sufficient to obtain the highest OY in the tested conditions. These findings demonstrated the importance of the optimisation of the reaction parameters for the acceptor reactions of the glucansucrases.
AtıfScopus2WoS4OpenAlex6İncele - MakaleAçık Erişim2022Scopus SJRQ4Isolation of Distinct Lactobacillaceae spp. with Functional Characteristics from Traditional Sourdough Samples; [Geleneksel Ekşi Hamur Örneklerinden Fonksiyonel Özelliklere Sahip Farklı Lactobacillaceae spp. İzolasyonu]
İspirli, Hümeyra; Dertli, Enes
Lactic Acid Bacteria (LAB) were isolated from traditional sourdough samples, and functional properties of selected LAB species were determined. Five distinct strains Limosilactobacillus fermentum LR1, Lacticaseibacillus rhamnosus LR2, Levilactobacillus senmaizukei CE37, Lactiplantibacillus plantarum CE48 and Limosilactobacillus reuteri KD44A were identified following the genotypic discrimination of hundred isolates. Presence of bacteriocin genes in identified species was determined by PCR, and sourdough isolates have been shown to carry bacteriocin genes although they vary according to species. Exopolysaccharide (EPS) production tests showed that the amount of EPS production varies in different media and different incubation conditions. Antimicrobial effects of 5 different LAB species were determined against Bacillus cereus BC 6830, which cause rop problems, and other pathogen species and also molds isolated from bread. Amylolytic activities of isolates, which are important in terms of technological roles, were determined genotypically and phenotypically. Finally, the phytase and phosphatase activities of these species were studied. This study was aimed to unveil the functional sourdough LAB species to be used for industrial purposes.
AtıfScopus4OpenAlex3
İncele - MakaleYalnız künye2022Scopus SJRQ1Characterisation and functional roles of a highly branched dextran produced by a bee pollen isolate Leuconostoc mesenteroides BI-20
Yilmaz, Mustafa Tahsin; İspirli, Hümeyra; Taylan, Osman; Taşdemir, Volkan; Sagdic, Osman; Dertli, Enes
Lactic Acid Bacteria (LAB) from different niches can be responsible for the production of distinct exopolysaccharides (EPS) that might possess important structural and technological features. In this respect, the aim of this study was to isolate an EPS producer LAB strain from bee pollen environment. Leuconostoc mesenteroides BI-20 with a slimy-mucoid colony morphology was identified from bee pollen and the structural, technological and functional characteristics of EPS produced by this strain were determined. EPS BI-20 was a highly branched dextran containing 20% (1 → 3)-linked α-D-glucose branches determined by 1H and 13C NMR analysis. The presence of (1 → 6)/(1 → 3)-linked α-D-glucose linkages in dextran BI-20 was also confirmed by FTIR analysis. Dextran BI-20, with a molecular weight of 1 × 108 Da, possessed strong thermal properties, amorphous nature and highly branched and fibrous microstructural characteristics determined by DSC, TGA, XRD and SEM analysis, respectively. In terms of functional roles, dextran BI-20 demonstrated strong antioxidant capacity detected by ABTS and CUPRAC tests. Finally, no digestion was observed in dextran BI-20 under simulated gastric conditions. Results of this study unveiled techno-functional characteristics of dextran BI-20 produced by a bee pollen isolate LAB strain.
AtıfScopus39WoS36OpenAlex39İncele