Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2024Scopus SJRQ3Optimization of asymmetric bioreduction conditions of 1-indanone by Leuconostoc mesenteroides N6 using a face-centered design-based multi-objective optimization model
Alamoudi, Mohammed; Özdemir, Akın; Dertli, Enes; Bolubaid, Mohammed; Alidrisi, Hassan M.; Taylan, Osman; Yılmaz, Mustafa Tahsin; Şahin, Engin
There has been an increasing interest in biocatalysts over the past few decades in order to obtain high efficiency, high yield, and environmentally benign procedures aiming at the manufacture of pharmacologically relevant chemicals. Lactic Acid Bacteria (LAB), a microbial group, can be employed as biocatalysts while performing asymmetric reduction of prochiral ketones. In this study, Leuconostoc mesenteroides N6 was used for the asymmetric bioreduction 1-indanone. And then, a novel and innovative face-centered design-based multi-objective optimization model was used to optimize experimental conditions. Also, the experimental design factors were defined as agitation speed, incubation period, pH, and temperature for optimization to acquire the maximum enantiomeric excess (ee) and conversion rate (cr) values. When using the face-centered design-based multi-objective optimization model, the optimum culture conditions corresponded to 96.34 and 99.42%, ee and cr responses, respectively, were pH = 5.87, incubation temperature = 35 °C, incubation period = 50.88 h, and agitation speed = 152.60 rpm. Notably, the validation experiment under the optimum model conditions confirmed the model results. This study demonstrated the importance of the optimization and the efficiency of the face-centered design-based multi-objective model.
AtıfScopus1WoS9OpenAlex1
İncele - MakaleAçık Erişim2023Scopus SJRQ3Optimization of asymmetric bioreduction conditions of 1-(thiophen-2-yl)ethanone by Weissella cibaria N9 using a desirability function-embedded face-centered optimization model
Bolubaid, Mohammed; Özdemir, Akın; Dertli, Enes; Alamoudi, Mohammed; Taylan, Osman; Karaboğa, Derviş; Yılmaz, Mustafa Tahsin; Şahin, Engin
Prochiral ketones can be effectively bio-reduced to chiral secondary alcohols by whole-cell biocatalysts, which are possible useful precursors to synthesize physiologically active chemicals and natural products. When whole-cell biocatalysts strains are used, bioreduction process can be influenced by various cultural factors, and it is vital to optimize these factors that affect selectivity, conversion rate, and yield. In this study, Weissella cibaria N9 was used as whole-cell biocatalyst for bioreduction of 1-(thiophen-2-yl)ethanone, and cultural design factors were optimized using a desirability function-embedded face-centered optimization model. For this, effects of pH (4.5–5.5–6.5, x 1), (2) temperature (25–30–35 °C, x 2), (3) incubation period (24–48–72 h, x 3), and (4) agitation speed (100–150–200 rpm, x 4) on two response variables; (1) ee (%) and (2) cr (%) were tested. Next, desirability function-embedded face-centered optimization model revealed that a pH of 6.43, a temperature of 26.04 °C, an incubation period of 52.41 h, and an agitation speed of 150 rpm were the optimum levels and the estimated ee and cr responses were 99.31% and 98.16%, respectively. Importantly, the actual experimental ee and cr responses were similar to the estimated values indicating the capability of the offered desirability function-embedded face-centered optimization model when using the optimum cultural conditions.
AtıfScopus1WoS1OpenAlex3İncele - 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 - MakaleYalnız künye2022Scopus SJRQ2The effect of flours of different immature cereal grains on sourdough and sourdough bread: Microbiological, rheological, textural and sugar profiles
Alkay, Zühal; Yılmaz, Mustafa Tahsin; Can, Aslı Muslu; İspirli, Hümeyra; Dertli, Enes
In this study, the utilization of LAB (Lactiplantibacillus plantarum, Levilactobacillus brevis, Furfurilactobacillus rossiae, Weissella cibaria) cultures with selected flours of different immature cereal grains (wheat, barley, oat and rye) on sourdough and sourdough bread was investigated. In total, 16 different sourdough breads were produced and microbiological, pH, TTA and rheological properties of sourdoughs at 0, 8 and 24 h were determined. At the beginning of the fermentation, while sourdoughs showed elasticity, they showed viscoelastic properties after 24 h of fermentation. The sugar profile of cereal grains at the stage of milk formation and the sugar groups presented in EPSs isolated from sourdoughs were revealed by HPLC analysis. The sugar groups in sourdoughs were glucose, xylose and arabinose, while the sugars in the immature cereal grains were glucose, fructose and mannose. The highest EPS production level (1882.69 ± 8.16) was observed in immature barley flour and Lpb. plantarum containing sourdough and all sourdoughs were found to contain glucan type EPSs. It was observed that the amount of EPS produced by the related species differed significantly under different grain conditions. Besides, it was observed that the sourdough breads produced were harder than the control bread. Novelty Impact Statement: Wheat, barley, oat and rye immature grains and four distinct LAB strains were used during sourdough fermentation. Immature grain type and LAB strain used were determinants for in situ exopolysaccharide (EPS) production. Viscoelastic properties of sourdough and textural properties of sourdough bread were affected by grains and LAB strain utilized.
AtıfScopus5WoS2İncele - MakaleYalnız künye2021Scopus SJRQ2Characterization of physicochemical and antioxidant properties of Bayburt honey from the North-east part of Turkey
Bayram, Nesrin Ecem; Kara, Hasan Hüseyin; Can, Aslı Muslu; Bozkurt, Fatih; Akman, Perihan Kübra; Vardar, Sevgi Umay; Çebi, Nur; Yılmaz, Mustafa Tahsin; Sağdıç, Osman; Dertli, Enes
The aim of this study was to determine the physicochemical properties, bioactive substance content, and microbiological quality of sixty different honey samples collected from twelve different regions of Bayburt, Turkey. The samples were analyzed for their sugar, moisture, total phenolic, total flavonoid contents, and water activity, conductivity, pH values and colour, antiradical activity, and DSC properties. As a result of physicochemical analyses, it was determined that the samples examined complied with the standard values defined in the Turkish Food Codex in terms of the parameters examined. The results of the study showed that the total phenolic content (219.43-768.82 mg GAE kg−1), total flavonoid content (31.29-118.7 mg CAE kg−1) and DPPH (12.98%-94.79%) parameters differ widely among the honey samples. A principal component analysis (PCA) was applied to correlate the characteristics of honey with honey samples collected from different regions. This is the first comprehensive and original report about the physicochemical properties of honey produced in Bayburt, a region close to the Anzer region where the most expensive honey, Anzer honey, is produced.
AtıfScopus19WoS17OpenAlex23İncele - 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 - 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 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 Erişim2015Scopus SJRQ2Impact of exopolysaccharide production on functional properties of some Lactobacillus salivarius strains
Mercan, Emin; İspirli, Hümeyra; Sert, Durmuş; Yılmaz, Mustafa Tahsin; Dertli, Enes
The aim of this work was to characterize functional properties of Lactobacillus salivarius strains isolated from chicken feces. Detection of genes responsible for exopolysaccharide (EPS) production revealed that all strains harbored a dextransucrase gene, but p-gtf gene was only detected in strain E4. Analysis of EPS production levels showed significant alterations among strains tested. Biofilm formation was found to be medium composition dependant, and there was a negative correlation with biofilm formation and EPS production. Autoaggregation properties and coaggregation of L. salivarius strains with chicken pathogens were appeared to be specific at strain level. An increment in bacterial adhesion to chicken gut explants was observed in L. salivarius strains with the reduction in EPS production levels. This study showed that strain-specific properties can determine the functional properties of L. salivarius strains, and the interference of these properties might be crucial for final selection of these strains for technological purposes.
AtıfScopus19WoS16OpenAlex21İncele
