Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleYayıncıda açık erişim2020Scopus SJRQ2Response of Japanese quails (Coturnix coturnix japonica) to dietary inclusion of Moringa oleifera essential oil under heat stress condition
Tekce, Emre; Bayraktar, Bülent; Aksakal, Vecihi; Dertli, Enes; Kamiloğlu, Aybike; Çinar Topcu, Kübra; Takma, Çiğdem; Gül, Mehmet; Kaya, Hacer
The present study was aimed at investigating the effects of the dietary use of different doses of Moringa oleifera essential oil (MOEO) on performance parameters, internal organ weights and meat quality in Japanese quails (Coturnix coturnix japonica) exposed to Heat Stress (HS). For this purpose, 320 male day-old quail chicks were used. Seven days of preliminary (physical exercise) and a 35-day fattening period were applied. The animals were divided into 8 groups, each including 40 animals according to temparature (C: 25 °C and SC: 37 °C) and dietary doses (C, 200, 400 and 600). Each group was divided into 4 subgroups, each comprising 10 animals. The consequences of this study showed that, in the stress-free (HSF) groups, while all of the different doses of dietary MOEO positively affected growth performance, feed intake and feed efficiency, in the HS groups, similar positive effects were observed with the use of 200 ppm of dietary MOEO. While no effect was detected on internal organ weights on Days 21 and 42 in the HSF and HS groups, a dose-dependent increase was determined in the intestinal pH value on day 42 in the HS group (p <.05). Additionally, in the analysis of meat quality on the 21st and 42 days compared to the controls, no effect was observed on the meat colour parameters value and TBARS level in the HS and HSF groups. Based on the consequences of this study, it is considered that, MOEO could be used as an alternative product in poultry, at a dose of 200 ppm, to reduce the detrimental effects of HS.HIGHLIGHTS Temperature stress, performance parameters and serious problems in the health of poultry. Moringa olifera helps regulate performance parameters in poultry exposed to heat stress. Since the addition of Moringa oleifera to the diets does not affect the organ weight and meat quality in 21 and 42 days, it does not cause any negative effects for the consumer.
AtıfScopus17WoS17OpenAlex19
İncele - MakaleAçık Erişim2020Optimization of exopolysaccharide production of Lactobacillus brevis E25 using RSM and characterization
Ermis, Ertan; Poyraz, Ecem; Dertli, Enes; Yilmaz, Mustafa Tahsin
Response surface methodology was used to determine the exopolysaccharide production of Lactobacillus brevis E25. The effects of three variables, temperature (30, 36 and 42 °C), incubation time (18, 33 and 48 h) and initial pH of growth medium (4.5, 5.5, and 6.5) were studied. Under optimum growth conditions, the amount of exopolysaccharide derived from Lactobacillus brevis E25 ranged from 10 to 35 gL-1. The size of EPS molecules ranged from 105 to 107 Da. Infra red spectrum analysis showed characteristics absorption peaks indicating the presence of-OH, C=O and C-H groups. Furthermore, only glucose was detected as monosaccharide in exopolysaccharide structure, revealing that the structure of exopolysaccharide is a homopolymeric glucan type. Based on the differential scanning calorimeter thermograms, exopolysaccharide’s melting temperature was observed around 116 °C.
AtıfScopus18OpenAlex18
İncele - MakaleYalnız künye2020Scopus SJRQ1Impact of glucan type exopolysaccharide (EPS) production on technological characteristics of sourdough bread
İspirli, Hümeyra; Özmen, D.; Yılmaz, Mustafa Tahsin; Sağdıç, O.; Dertli, Enes
In this study, technological role of α-glucan with (α1-3) and (α1-6) glycosidic linkages produced by Lactobacillus reuteri E81 on sourdough rheology and bread texture was investigated. To achieve this, a glucan deficient ΔgtfA mutant was produced by the deletion of the glucansucrase gene from strain E81. By comparison of glucan-positive and glucan-negative strains for rheological properties of sourdough revealed that in situ α-glucan production resulted in higher elasticity in sourdough. However, no additional effect of in situ glucan on textural characteristics of bread was observed although addition of glucan ex situ at 0.09% level significantly decreased bread hardness. Scanning Electron Microscopy (SEM) images of lyophilized sourdoughs confirmed association of glucan and starch granules forming a film like structure in sourdough.
AtıfScopus71WoS58OpenAlex67İncele - MakaleAçık Erişim2020Scopus SJRQ1Synthesis and characterisation of alternan-stabilised silver nanoparticles and determination of their antibacterial and antifungal activities against foodborne pathogens and fungi
Yilmaz, Mustafa Tahsin; İspirli, Hümeyra; Taylan, Osman; Dertli, Enes
In this study, alternan isolated from Lactobacillus reuteri E81 was used as the stabilising agent to produce alternan-stabilised silver nanoparticles (AgNPs-Alt) and AgNPs-Alt were characterized and their antibacterial and antifungal activities were tested. The formation and the stability of AgNPs-Alt were determined by UV–vis spectroscopy analysis. SEM and TEM analysis revealed the uniform morphology of AgNPs-Alt with an average size of ~50 nm. The crystalline nature of the AgNPs-Alt was confirmed by XRD analysis. The interactions of alternan functional groups with silver was observed by FTIR analysis and thermal characteristics of AgNPs-Alt were determined by DSC analysis. Finally, the antibacterial and the antifungal activities of AgNPs-Alt were tested and AgNPs-Alt revealed inhibitory effects to pathogenic strains at 0.25 mg ml−1 concentration and this activity was observed to be concentration dependent. For the antifungal activity, a higher level of AgNPs-Alt was required compared to the antibacterial activity.
AtıfScopus35WoS31OpenAlex36İncele - MakaleYalnız künye2020Scopus SJRQ4Green synthesis of chiral aromatic alcohols with Lactobacillus kefiri P2 as a novel biocatalyst
Baydaş, Yasemin; Dertli, Enes; Şahin, Engin
Biocatalytic reduction is a very important field of research in synthetic organic chemistry. Herein, three different Lactic Acid Bacteria (LAB) strains were evaluated for their bioreduction potential using acetophenone as a model substrate. Among these strains, Lactobacillus kefiri P2 strain was determined as the best asymmetric reduction biocatalyst. Reaction optimization parameters such as reaction time, temperature, agitation speed and pH were systematically optimized using Lactobacillus kefiri P2 strain and model substrate acetophenone. Under these optimized reaction conditions, secondary chiral alcohols were obtained by bioreduction of various prochiral ketones with results up to 99% enantiomeric excess. In addition, the steric and electronic effects of substituents on enantioselectivity and conversion were evaluated. It has been shown that Lactobacillus kefiri P2 biocatalyst was an effective catalyst for asymmetric reduction. This method provides an environmentally friendly method for the synthesis of optically pure alcohols and an alternative approach to chemical catalysts.
AtıfScopus24WoS22OpenAlex22İncele - MakaleAçık Erişim2020Scopus SJRQ2Bioactive Characteristics of Wild Berberis vulgaris and Berberis crataegina Fruits
Eroǧlu, Arzu Yaşar; Çakir, Özlem; Saǧdiç, Mustafa; Dertli, Enes
There is an increasing trend to find novel sources of products with high antioxidant capacity and wild fruits are very good examples for these sources. In this study, fruits of Berberis vulgaris and Berberis crataegina, naturally grown in Bayburt province of Turkey, were tested for their physicochemical features, antioxidant capacities, phenolic compound profiles, and antimicrobial activities. The physicochemical analysis of the fruits revealed that the dry matter content, ash content, pH, and aw values were between 28.47% and 41.61%, 0.65% and 2.13%, 2.44 and 3.25, and 0.996 and 0.97, respectively. The total phenolic content of the fruits was determined by the Folin-Ciocalteu methodology, and for the determination of the antioxidant capacity of the fruits, DPPH, ABTS, and β-carotene bleaching methods were performed and a high level of antioxidant activity was observed. HPLC analysis was applied to identify the phenolic content of the fruits, and gallic acid and chlorogenic acid were found to be the dominant phenolic compounds in Berberis fruits. The water extracts of the Berberis fruits were tested against important foodborne pathogenic bacteria as potential antimicrobials. The extracts inhibited the growth of Bacillus cereus, Salmonella typhimurium, Yersinia enterocolitica, and Staphylococcus aureus at significant rates. This study revealed the potential antioxidant and antimicrobial characteristics of wild-type B. vulgaris and B. crataegina that can be used for different future applications.
AtıfScopus36WoS27OpenAlex26İncele - MakaleAçık Erişim2020Scopus SJRQ2Bifidogenic effect and in vitro immunomodulatory roles of melibiose-derived oligosaccharides produced by the acceptor reaction of glucansucrase E81
İspirli, Hümeyra; Kaya, Yasemin; Dertli, Enes
Glucansucrases are responsible for the production of α-glucans using sucrose as the substrate. Glucansucrases may also produce different oligosaccharides by transferring the glucose moiety from sucrose to a variety carbohydrates acting as acceptor nucleophile. In this study, melibiose-derived oligosaccharides were produced by the glucansucrase from Lactobacillus reuteri E81 expressed without the N-terminal region (GtfA-ΔN). The reaction products were characterized by TLC, LC-MS and NMR analysis and it was found that GtfA-ΔN synthesized melibiose-derived oligosaccharides (DP3 and DP4) by adding glucose units through alpha 1->3 or 1->6 glycosidic bond. The functional characteristics of these melibiose-derived oligosaccharides were determined by testing the immune-modulatory functions in HT-29 cells and testing their growth promoting effects for important probiotic and pathogenic strains. The melibiose-derived oligosaccharides triggered the production of anti-inflammatory cytokine IL-10 and pro-inflammatory cytokine TNF-α depending on their concentrations. Finally, melibiose-derived oligosaccharides showed bifidogenic effect as potential prebiotics.
AtıfScopus15WoS14OpenAlex15İncele - MakaleAçık Erişim2020Scopus SJRQ3Determining the optimum model parameters for oligosaccharide production efficiency using response surface integrated particle swarm optimization method: an experimental validation study
Şensoy, Abdullah Tahir; İspirli, Hümeyra; Dertli, Enes
Glucansucrases (GTFs) catalyzes the synthesis of α-glucans from sucrose and oligosaccharides in the presence of an acceptor sugar by transferring glucosyl units to the acceptor molecule with different linkages. The acceptor reactions can be affected by several parameters and this study aimed to determine the optimal reaction parameters for the production of glucansucrase-based oligosaccharides using sucrose and maltose as the donor and acceptor sugars, respectively via a hybrid technique of Response Surface Method (RSM) and Particle Swarm Optimization (PSO). The experimental design was performed using Central Composite Design and the tested parameters were enzyme concentration, acceptor:donor ratio and the reaction period. The optimization studies showed that enzyme concentration was the most effective parameter for the final oligosaccharides yields. The optimal values of the significant parameters determined for enzyme concentration and acceptor:donor ratio were 3.45 U and 0.62, respectively. Even the response surface plots for input parameters verified the PSO results, an experimental validation study was performed for the reverification. The experimental verification results obtained were also consistent with the PSO results. These findings will help our understanding in the role of different parameters for the production of oligosaccharides in the acceptor reactions of GTFs.
AtıfScopus6WoS6OpenAlex6
İncele - MakaleAçık Erişim2020Scopus SJRQ1An integrated neural-fuzzy methodology for characterisation and modelling of exopolysaccharide (EPS) production levels of Leuconostoc mesenteroides DL1
Kabli, Mohammad; Yilmaz, Mustafa Tahsin; Taylan, Osman; Kaya, Yasemin; İspirli, Hümeyra; Basahel, Abdulrahman; Sagdic, Osman; Dertli, Enes
Optimisation of exopolysaccharides (EPS) production in Lactic Acid Bacteria (LAB) is an important task as EPS production can be affected by different parameters. In this respect, this study aimed to characterise the structure of an EPS from Leuconstoc mesenteroides DL1 strain and to optimise the EPS production by determination of the effects of incubation time, sucrose concentration, incubation temperature and initial levan concentration (input parameters) using integrated ANNs (Artificial neural networks) and fuzzy modelling approaches. The characterisation of the EPS monomeric composition by HPLC analysis revealed that EPS DL1 was composed of glucose and fructose. The 1H and 13C NMR spectra of EPS DL1 also confirmed the glucan and fructan production. The effects of the input parameters on glucan and fructan production levels as output parameters by DL1 were optimised using neural network and fuzzy modelling tools. The fuzzy model was developed based on the recognition of basic elements of input-output parameters, and the power of ANNs used for system identification. A structural analysis was carried out to improve the flexibility of fuzzy model, and to design the unknown mappings of the input and output parameters more robustly. The parameters then were fine-tuned by qualitative reasoning to establish the relations of input output parameters using membership functions (MFs) and their intervals determination. A hybrid training algorithm was employed for parameter identification, MFs and their interval determination to obtain the fuzzy model. The model can predict the outcome parameters; glucan and fructan with high accuracy for the predetermined input parameters.
AtıfScopus8WoS7OpenAlex9İncele - Proje2019Nadir Bir Ekzopolisakkarit Olarak Alternanın Fonksiyonel Etkilerinin Belirlenmesi, Alternan Üretiminden Sorumlu Alternansükraz Enziminin Ekspresyonu ve Aktivitesinin Tespiti
Yılmaz, Mustafa Tahsin; Şimşek, Ömer; Dertli, Enes
Laktik Asit Bakterileri (LAB)?nin starter kültür olarak islevlerine ilave olarak son dönemde bu önemli mikrobiyal grubun ürettigi fonksiyonel metabolitler üzerinde durulmaktadır. Bu metabolitlerin basında da LAB türleri tarafından in situ olarak üretilip gıda maddelerinin fizikokimyasal niteliklerini gelistirebilen ekzopolisakkaritler (EPS) gelmektedir. LAB türlerinde yapısal olarak glukoz/fruktoz?dan olusabilen homopolimerik EPS üretimi ucuz substrat ve yüksek miktarda üretim nedeniyle temel olarak ?-glukan üretimi çerçevesinde sekillenmektedir ve sükrozun substrat olarak kullanılması ile ?-glukan üretiminden glukansükrazlar sorumludur. LAB türlerinde glukansükrazların aktivitesi ile alternan gibi farklı yapılarda ?-glukan üretimi gerçeklesebilmektedir. Son dönemde LAB türlerinde ortaya çıkartılan ?-glukan üretebilen bir diger enzim grubu da sükrozda inaktif ancak amiloz gibi ?-1- 4 glikozidik bagı içeren substratlara etki edip açıga çıkan glukoz ünitelerini farklı baglar ile baglayabilen glukanotransferazlardır. Her iki enzim grubu ile de farklı yapılarda fonksiyonel etkileri olabilecek polisakkarit/oligosakkaritlerin üretimi gerçeklesebilmekte olup, bu enzimlerin aktivitelerinin belirlenerek üretebildikleri polisakkarit/oligosakkaritlerin karakterizasyonu ve bu bilesenlerin fonksiyonel etkilerinin tespiti son derece önemli bir husustur. Bu baglamda bu projenin amacı eksi hamurdan izole edilen alternan üreticisi oldugu gösterilen Lactobacillus reuteri E81?de alternan üretiminin eksi hamur üretimi açısından fonksiyonel etkilerini ortaya koymak, alternan üretiminden sorumlu glukansükrazın ve yine aynı bakteride açıga çıkartılan 4,6-?-glukanotransferazın aktivitesinin ve sırasıyla verici-alıcı reaksiyonları ve farklı substratlarda üretebildikleri oligosakkaritlerin karakterizasyonu ve bu oligosakkaritlerin bagısıklık düzenleyici ve prebiyotik potansiyellerinin belirlenmesidir. Proje kapsamında öncelikle Lactobacillus reuteri E81 eksi hamurdan izole edilip ürettigi alternanın fizikokimyasal karakterizasyonu gerçeklestirilmis ve bakterinin bütün genom sekansı açıga çıkartılmıstır. L. reuteri E81?in genom analizi bu bakteri de glukansükraz (gtfA) enzimine ilaveten 4,6-?-glukanotransferaz (gtfB) enzimini kodlayabilecek bir genin genomda yer aldıgını göstermistir. Ilk olarak eksi hamur ve ekmeginin nitelikleri açısından alternan üretiminin fonksiyonel etkilerinin anlasılabilmesi için gtfA geni L. reuteri E81?den silinmis ve L. reuteri E81 ve alternan üretemeyen L. reuteri E81 ?gtfA ile eksi hamur üretilip eksi hamurun fizikokimyasal özellikleri ve eksi hamur ekmeginin yapısal karakteristikleri üzerine alternan üretiminin etkileri açıga çıkartılmıs ve alternan üretiminin hamunun viskoelastik yapısının gelisimine katkı sagladıgı ortaya konmustur. Ikinci olarak L. reuteri E81?den gtfA ve gtfB genleri Escherichia coli BL21 (DE3) hücrelerinde üretilip glukansükraz (GTFA) ve 4,6-?- glukanotransferaz (GTFB) enzimlerinin aktivitesi ortaya konmus ve ürettikleri ?-glukanların yapıları Nükleer Manyetik Rezonans (NMR) spektroskopisi ile belirlenmistir. Takiben GTFA enziminin sükroz ve farklı seker alıcılarla ve GTFB enziminin ise ?-1-4 bagı içeren farklı substratlardan üretebildikleri oligosakkaritler Ince Tabaka Kromatografisi (TLC), NMR ve Sıvı Kromatografisi-Kütle Spektroskopisi (LC-MS) analizleri ile karakterize edilmis ve her iki enzimin farklı reaksiyonlarda özgün oligosakkaritleri üretme kabiliyetinde oldukları gösterilmistir. Son olarak GTFA ve GTFB ile üretilen bu oligosakkaritlerin fonksiyonel etkileri in vitro olarak HT-29 kolon hücrelerinde IL-10, IL-4, IL-12 ve TNF-? sitokinlerinin indüklenme potansiyelleri ve probiyotik ve patojen bakterilerin gelisimi üzerine potansiyel etkileri incelenerek ortaya konmus ve oligosakkarit düzeyinde fonksiyonel etkinin degisiklik gösterebildigi açıga çıkartılmıstır.
- MakaleAçık Erişim2019Scopus SJRQ1Characterization of a 4,6‑α‑glucanotransferase from Lactobacillus reuteri E81 and production of malto-oligosaccharides with immune-modulatory roles
İspirli, Hümeyra; Şimşek, Ömer; Skory, Christopher; Sağdıç, Osman; Dertli, Enes
A wide number of Lactic Acid Bacteria (LAB) species produce α-glucans with their ability to synthesize glucansucrases (GS) which use sucrose as substrate for the glucan production. Recently another group of enzymes in LAB gained special interest for their ability to produce α-glucans targeting the substrates containing α1-4-linkages and synthesizing new (α1-6) or (α1-3)–linkages as α‑glucanotransferases. In this study, a putative 4,6‑α‑glucanotransferase (GTFB) from sourdough isolate Lactobacillus reuteri E81 was identified and expressed in Escherichia coli. The biochemical characterization of the GTFB-E81 confirmed its function as it cleaved the α1-4-linkages in different substrates and produced new gluco-oligomers/polymers containing α1-6 linkages together with the α1-4-linkages detected by NMR analysis. GTFB-E81 produced malto-oligosaccharides targeting maltose and maltoheptaose as substrates with up to DP 8 detected by TLC and ESI-MS/MS analysis. The functional roles of these malto-oligosaccharides were determined by testing their immune-modulatory functions in HT29 cells and they triggered the production of anti-inflammatory 1L-4 and pro-inflammatory IL-12 cytokines.
AtıfScopus43WoS40OpenAlex42İncele - MakaleAçık Erişim2019Scopus SJRQ2Physicochemical characterisation of an α-glucan from Lactobacillus reuteri E81 as a potential exopolysaccharide suitable for food applications
İspirli, Hümeyra; Sagdic, Osman; Yılmaz, Mustafa Tahsin; Dertli, Enes
Lactobacillus reuteri strain (E81) is an alpha glucan producer from traditional sourdough and the physicochemical characteristics of this glucan was determined in this study. The HPLC analysis confirmed the presence of glucose as the only sugar monomer in the repeating structure of this exopolysaccharide (EPS). The functional groups within the glucan structure was detected by FTIR analysis. The scanning electron microscopy (SEM) analysis demonstrated the web-like branched structure of the glucan. Morphological characterisation of the glucan E81 by atomic force microscopy (AFM) analysis showed clear roundness lumps and chains. Importantly, thermal characteristics of glucan E81 determined by thermogram analysis (TGA) and differential scanning calorimeter (DSC) analysis revealed that glucan E81 has a melting point of 290 °C making it promising to be used in thermal processed foods including sourdough bread.
AtıfScopus77WoS71OpenAlex77İncele - MakaleAçık Erişim2019Scopus SJRQ1Electrospraying method for fabrication of essential oil loaded-chitosan nanoparticle delivery systems characterized by molecular, thermal, morphological and antifungal properties
Yilmaz, Mustafa Tahsin; Yilmaz, Azime; Akman, Perihan Kubra; Bozkurt, Fatih; Dertli, Enes; Basahel, Abdulrahman; Al-Sasi, Basil; Taylan, Osman; Sagdic, Osman
Fabrication of essential oil loaded-chitosan nanoparticles using electrospraying technique appears to be a novel strategy to develop thermally stable nanoparticles possessing higher encapsulation efficiency and particle stability. This study aims to fabricate chitosan nanoparticles (CNPs) loaded with Origanum vulgare essential oil (OEO, Origanum vulgare L.) at different proportions (OEO/CH proportions of 0:1, 0.0625:1, 0.125:1, 0.25:1 and 0.5:1 mL/g) using electrospraying technique. The CNPs were characterized in term of their particle size and stability (dynamic light scattering), encapsulation efficiency (spectrophotometry), and molecular (Fourier transform infrared spectroscopy), thermal (differential scanning calorimetry/thermogravimetric analysis), morphological (scanning electron microscopy) and antifungal (agar dilution method) and fungistatic activity properties. The average particle sizes of the CNPs ranged between 290 and 483 nm with a spherical morphology. Positively charged surface characteristics were observed to increase with the increment of OEO concentration in CNPs. The encapsulation efficiency values were determined in the range of 70.1 and 79.6%. The molecular and thermal analyses exposed very decent encapsulation of OEO into thermally stable chitosan nanoparticles. Morphological analysis verified the spherical shapes of these nanoparticles. Above all, the antifungal effectiveness of OEO against the Alternaria alternata AY1 could be significantly (p < 0.05) increased by its encapsulation into chitosan nanoparticles fabricated by the electrospraying technique. Consequently, it can be stated that the electrospraying technique developed is able to fabricate thermally stable nanoparticles owning higher encapsulation efficiency and particle stability. The results and findings suggest that the electrospraying technique would be a promising method to fabricate chitosan-based nanoparticles as an antimicrobial agent to control their release in a prolonged preservative effect in cosmetic, pharmaceutical and food applications for adjustable dosage forms. Industrial relevance: The fungal agents such as Alternaria alternata cause great damages on post-harvest fresh fruits and vegetables, thus leading to a great economical lose. Therefore, a great variety of methods in struggling with disease have been previously proposed. Nowadays, the most effective leading methods to struggle against plant diseases are those applied with synthetic fungicides to minimize such lose in post-harvest fruit and vegetables. However, intensive and unconscious use of the fungicides leads the pathogens to develop resistance against these agents as well as to accumulation of chemical residues in soil, water and air and finally to formation of carcinogenic effects on human health. Nowadays, a great effort is being exerted to develop novel biodegradable and natural antimicrobial agents for struggling fungal spoilage in postharvest products. Essential oils are among the most widely used natural struggling methods. Essential oils obtained from plants have been extensively used since they are natural antimicrobial agents. However, they cannot be effectively used in spite of their extensive applications. Recently, some researches in the field of nanotechnology have demonstrated that the effectiveness of active substances could be increased by using some techniques. In this respect, we aimed at developing essential-oil-loaded-chitosan-nanoparticle delivery systems using an electrospraying deposition system to prevent fungal colonization on food and plant materials. By increasing antifungal effectiveness of essential oils by their encapsulation into nanoparticles, it will be possible to decrease the levels of regularly applied dose and reflect the obtained outcomes to the food and agriculture industry. This study is the first example of production of essential oil loaded nanoparticles using the electrospraying-hydrodynamic process and showed that encapsulation of oregano essential oil into chitosan based nanoparticles (CNPs) by using the electrospraying deposition technique considerably increased the antifungal effectiveness of the Origanum vulgare essential oil. Our results highlight the potential use of the chitosan nanoparticles (CNPs) loaded with different amounts of Origanum vulgare in food and agriculture industry as an effective fungicidal material against Alternaria alternata, suggesting that the CNPs can be promising tools to compete with synthetic fungicide counterparts and limit use of synthetic ones for struggling of food and plant pathogens. Therefore, the results of this study should be of great importance to industrial applications in terms of development of natural, but effective preservatives as alternative to synthetic ones. In this respect, the CNPs would find a great industrial application area in the food and agriculture industry which seek natural preservatives due to the recent health concerns.
AtıfScopus119WoS101OpenAlex118İncele - MakaleAçık Erişim2019Scopus SJRQ1Characterization of chemical, molecular, thermal and rheological properties of medlar pectin extracted at optimum conditions as determined by Box-Behnken and ANFIS models
Al-Amoudi, Rami H.; Taylan, Osman; Kutlu, Gozde; Can, Asli Muslu; Sagdic, Osman; Dertli, Enes; Yilmaz, Mustafa Tahsin
In this work, response surface methodology and adaptive neuro-fuzzy inference system approaches were used to predict and model effect of extraction conditions of pectin from medlar fruit (Mespilus germanica L.). The pectin extracted at optimized conditions (89 °C, 4.83 h and 4.2 pH) could be classified as high methoxyl pectin. Sugar composition analysis showed that pectin was mainly composed of D-galacturonic acid, L-arabinose, L-rhamnose, D-galactose and D-glucose. Fourier Transform Infrared Spectroscopy, RAMAN and nuclear magnetic resonance spectra confirmed molecular structure, revealing presence of D-galacturonic acid backbone. X-ray diffraction patterns revealed an amorphous structure. Differential scanning calorimetry showed endothermic (123 °C) and exothermic peaks (192 °C). Thermogravimetric analysis revealed three decomposition regions, 50–225 °C, 225–400 °C and 400–600 °C. Steady and dynamic shear analyses revealed that pectin had a pseudo-plastic behavior with storage (G′) and loss (G″) modulus increasing with increment in frequency, indicating viscoelastic structure more predominantly elastic than viscous.
AtıfScopus89WoS79OpenAlex83İncele - MakaleYalnız künye2019Scopus SJRQ3Response surface methodology as optimization strategy for asymmetric bioreduction of acetophenone using whole cell of Lactobacillus senmaizukei
Çolak, Nida Sezin; Şahin, Engin; Dertli, Enes; Yilmaz, Mustafa Tahsin; Taylan, Osman
Whole cell applications are one of the main methodologies for the bioreduction of prochiral ketones to obtain enantiomerically rich chiral secondary alcohols which are mainly affected by the culture parameters of the whole cell. In this study, whole cell of Lactobacillus senmaizukei as a safe Lactic Acid Bacteria (LAB) was used for the reduction of acetophenone and Response Surface Methodology (RSM) application was used to optimize the culture parameters in terms of temperature, pH, incubation time, and agitation level to obtain the highest enantiomeric excess (ee) and conversion rate. The predicted optimum conditions for the bioreduction with whole cell Lactobacillus senmaizukei were found to be pH of 5.25, temperature of 25 °C, incubation time of 72 hr, and agitation level of 100 rpm. Importantly, the efficiency of the reduction of the acetophenone was significantly affected by the linear and quadratic effects of culture parameters. These findings are important to show the role of culture parameters for the bioreduction reactions and also the efficiency of the RSM technique to optimize these parameters.
AtıfScopus10WoS10OpenAlex11İncele - MakaleAçık Erişim2019Scopus SJRQ3Characterization of a glucansucrase from Lactobacillus reuteri E81 and production of malto-oligosaccharides
İspirli, Hümeyra; Yüzer, Mustafa Onur; Skory, Christopher; Colquhoun, Ian J.; Sağdıç, Osman; Dertli, Enes
Glucansucrases, which can be produced by different Lactic Acid Bacteria (LAB), catalyze the synthesis of α-glucans with different structures and properties using sucrose as substrate. In this study, a novel glucansucrase (GTFA) from Lactobacillus reuteri E81 was identified and heterologously expressed. Alignments of GTFA with other glucansucrases revealed its novelty and a putative 3D model structure was obtained. The biochemical properties of the truncated enzyme without the N-terminal variable region, GTFA-ΔN, was characterized. The Km and Vmax were found to be 7.5 mM and 1.49 IU/mg, respectively, and it showed optimum activities at pH 7 and at 50 °C. The GTFA-ΔN produced in vitro an α-glucan with (α1 → 3) and (α1 → 6) glycosidic linkages using sucrose as the substrate. Importantly, GTFA-ΔN synthesized DP = 9 oligosaccharides using sucrose and maltose as the donor and acceptor sugars, respectively, as detected by TLC, HPLC, LC-MS and NMR analysis.
AtıfScopus40WoS40OpenAlex40İncele - MakaleYalnız künye2019Scopus SJRQ1Effect of electrospun nisin and curcumin loaded nanomats on the microbial quality, hardness and sensory characteristics of rainbow trout fillet
Meral, Raciye; Alav, Aslıhan; Karakas, CananYagmur; Dertli, Enes; Yilmaz, Mustafa Tahsin; Ceylan, Zafer
Nisin and curcumin loaded (NCL) nanomats having 172 nm mean diameter were successfully fabricated. The effect of NCL nanomats in terms of limitation of Total Mesophilic Aerobic (TMAB) and Lactic acid bacteria (LAB) in fish fillets was tested during the analysis period. On the 4th day, while TMAB load of C was 6.61 log CFU g−1, that of the sample coated with NCL nanomats was found to be 3.28 log CFU g−1. TMAB load of control samples reached above 6 log CFU g−1 on the 4th day of cold storage, TMAB load of fish samples coated with nanomats reached the same level up to the 12th day. The shelf life of coated fillets was extended to 12 day. 3–4 logarithmic decrease was obtained in LAB count by NCL nanomats during the analysis period. On the 4th storage day, the hardness value of C sample decreased 21% compared to NCL samples. All sensory attributes of C samples were acceptable by the 4th day of the storage; while sensory attributes of NCL samples were acceptable by the 10th day of storage. The study revealed that nisin and curcumin loaded nanomats could be effectively used to improve the quality of fish fillets.
AtıfScopus92WoS84OpenAlex91İncele - MakaleAçık Erişim2019Scopus SJRQ2Preparation of gentiobiose-derived oligosaccharides by glucansucrase E81 and determination of prebiotic and immune-modulatory functions
İspirli, Hümeyra; Colquhoun, Ian J.; Şahin, Engin; Sagdic, Osman; Dertli, Enes
Gentiobiose-derived oligosaccharides were synthesized by the acceptor reaction of glucansucrase E81 obtained from Lactobacillus reuteri E81 with sucrose and gentiobiose as donor-acceptor sugars, respectively. The reaction products were monitored by TLC analysis and gentiobiose-derived oligosaccharides up to DP 8 were formed during the acceptor reaction as determined by ESI-MS/MS analysis. The glycosylation of the gentiobiose with α-(1 → 6) linkages and α-(1 → 3) linkages was shown by 1H and 13C NMR analysis confirming the structure of these gentiobiose-derived oligosaccharides. The in vitro prebiotic function of the oligosaccharides was determined in which probiotic strains were stimulated whereas no growth was observed in pathogen strains. Gentiobiose-derived oligosaccharides showed immune-modulatory functions in vitro and triggered the production of IL-4, IL12 and TNF-α cytokines in HT29 cells in a dose dependent manner. This study showed the production and functional characterisation of gentiobiose-derived oligosaccharides establishing a promising avenue for future applications.
AtıfScopus26WoS21OpenAlex22İncele - MakaleYalnız künye2019Scopus SJRQ3Biocatalyzed Enantiomerically Pure Production of (S)-Phenyl(thiophen-2-yl)methanol
Şahin, Engin; Dertli, Enes
Chiral aryl heteroaryl methanols are important precursors for the synthesis of pharmaceutically important molecules. The aims of this study were to use a biocatalyst that could efficiently bioreduce phenyl(thiophen2- yl) methanone 1 to (S)-phenyl(thiophen-2-yl) methanol 2, to identify the impact of the physicochemical factors that might affect the bioreduction by the biocatalyst, and to obtain multigram production of aryl heteroaryl secondary alcohol 2 with the biocatalyst under optimized conditions. Over the years, the (S)phenyl( thiophen-2-yl) methanol was synthesized on a small scale using a chemical catalyst without its enantiomerically pure form. In this study, Lactobacillus paracasei BD101 was used for the asymmetric reduction of phenyl(thiophen-2-yl) methanone to (S)-phenyl(thiophen-2-yl) methanol in the large-scale production. The asymmetric bioreduction conditions were systematically optimized, and the production of 3.77 g of (S)-phenyl(thiophen-2-yl) methanol was carried out in enantiomerically pure form > 99% enantiomeric excess (ee), > 99% conversion, and 90% yield. This method obtained with this biocatalyst is a process that can be used industrially in terms of conversion, ee, and yield. This study provides guidance for the application of L. paracasei BD101 in the production of optically active aryl heteroaryl alcohols.
AtıfScopus12WoS12OpenAlex12İncele - MakaleYalnız künye2019Scopus SJRQ1Partial characterization of a levan type exopolysaccharide (EPS) produced by Leuconostoc mesenteroides showing immunostimulatory and antioxidant activities
Taylan, Osman; Yilmaz, Mustafa Tahsin; Dertli, Enes
Leuconostoc mesenteroides S81 was isolated from traditional sourdough as an exopolysaccharide (EPS) producer strain. The monosaccharide composition of the EPS from strain S81 was characterized by HPLC analysis and only fructose was found in the repeating unit structure. The NMR spectroscopy analysis revealed that EPS was a levan type EPS as a β-(2 → 6)-linked fructan. The FTIR analysis further confirmed the presence of the furanoid rings in the EPS structure. The levan S81 showed high level of thermal stability determined by DSC and TGA analysis. The lyophilised levan S81 showed a sheet-like compact morphology and its aqueous solution formed spheroidal lumps with a compact structure detected by SEM and AFM analysis, respectively. Importantly the levan S81 showed a high level of immunomodulatory role, induced the anti-inflammatory cytokine IL-4, and exhibited a strong antioxidant capacity with EC50 value 1.7 mg mL−1 obtained by hydroxyl radical scavenging activity test under in vitro conditions. These findings reveal potential of levan S81 for technological purposes and as a potential natural immunomodulatory and antioxidant.
AtıfScopus132WoS112OpenAlex126İncele