Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2019Scopus SJRQ3Production of enantiomerically pure (S)-phenyl(pyridin-2-yl)methanol with Lactobacillus paracasei BD101
Şahin, Engin; Serencam, Hüseyin; Dertli, Enes
Asymmetric reduction studies of heteroaryl ketones, including phenyl(pyridin-2-yl)methanone in enantioselective form with biocatalysts are very few, and chiral heteroaryl alcohols have been synthesized generally in the small scale. In this study, seven bacterial strains have been used to produce the (S)-phenyl(pyridin-2-yl)methanol in high enantiomeric excess and yield. Among the tested strains, Lactobacillus paracasei BD101, was found to be the best biocatalyst for the reducing phenyl(pyridin-2-yl)methanone to the (S)-phenyl(pyridin-2-yl)methanol at gram scale. The asymmetric bioreduction conditions were systematically optimized using L. paracasei BD101, which demonstrated excellent enantioselectivity and high level of conversion for the bioreduction reaction. (S)-phenyl(pyridin-2-yl)methanol, which is an analgesic, was produced enantiomerically pure form in the first time on gram scale using a biocatalyst. In total, 5.857 g of (S)-phenyl(pyridin-2-yl)methanol in enantiomerically pure form (>99% enantiomeric excess) was obtained in 52 h with 93% yield using whole cells of L. paracasei BD101. Enantiomerically pure (S)-phenyl (pyridin-2-yl)methanol, which is an analgesic, was first produced in the gram scale using a biocatalyst with excellent ee (>99%) and yield (93%).
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İncele - MakaleYalnız künye2019Scopus SJRQ3Synthesis and Biological Evaluation of Novel Tricyclic Pyrrolidinyl (R)-Alcohols and Amines
Şahin, Engin; Kılıç, Hamdullah; Törnük, Fatih; Dertli, Enes
Three new tricyclic pyrrolidinyl alcohols and three tricyclic pyrrolidinyl amines were synthesized, and the antibacterial activities of these compounds were tested against Salmonella enterica subsp. enterica serovar Typhimurium, Escherichia coli O157:H7, Staphylococcus aureus, and Listeria monocytogenes. All tested pyrrolidinyl alcohols and amines showed antibacterial activity to the tested pathogens, but this activity was dependent on the final concentration of the tested compound, and the structure of these compounds were also important for this antibacterial activity. Of the tested compounds, (2R)-2-(octahydro-4,8-ethanocyclohepta[c] pyrrol2(1H)-yl)-2-phenylethanamine (2c) was the most effective compound among the tested pyrrolidinyl alcohols and amines. This study shows a good example of finding new antimicrobials in order to control pathogenic bacteria.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2019Scopus SJRQ3Whole cell application of Lactobacillus paracasei BD101 to produce enantiomerically pure (S)-cyclohexyl(phenyl)methanol
Şahin, Engin; Serencam, Hüseyin; Dertli, Enes
In this study, a total of 10 bacterial strains were screened for their ability to reduce cyclohexyl(phenyl)methanone 1 to its corresponding alcohol. Among these strains, Lactobacillus paracasei BD101 was found to be the most successful biocatalyst to reduce the ketones to the corresponding alcohols. The reaction conditions were systematically optimized for the reducing agent L paracasei BD101, which showed high enantioselectivity and conversion for the bioreduction. The preparative scale asymmetric reduction of cyclohexyl(phenyl)methanone (1) by L paracasei BD101 gave (S)-cyclohexyl(phenyl)methanol (2) with 92% yield and >99% enantiomeric excess. The preparative scale study was carried out, and a total of 5.602 g of (S)-cyclohexyl(phenyl)methanol in high enantiomerically pure form (>99% enantiomeric excess) was produced. L paracasei BD101 has been shown to be an important biocatalyst in asymmetric reduction of bulky substrates. This study demonstrates the first example of the effective synthesis of (S)-cyclohexyl(phenyl)methanol by the L paracasei BD101 as a biocatalyst in preparative scale.
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İncele - MakaleYalnız künye2019Scopus SJRQ3Production of enantiomerically enriched chiral carbinols using Weissella paramesenteroides as a novel whole cell biocatalyst
Tozlu, Caner; Şahin, Engin; Serencam, Hüseyin; Dertli, Enes
In this study, four bacterial strains were tested for their ability to reduce acetophenones to its corresponding alcohol. Among these strains Weissella paramesenteroides N7 was found to be the most successful biocatalyst to reduce the ketones to the corresponding alcohols. The reaction conditions were systematically optimized for W. paramesenteroides N7 that resulted in high enantioselectivity and conversion rates for the bioreduction. The scale-up asymmetric reduction of 1-(4-methoxyphenyl) propan-1-one (1r) by W. paramesenteroides N7 gave (R)-1-(4-methoxyphenyl) propan-1-ol (2r) with 94% yield and >99% enantiomeric excess. This is the first report showing the synthesis of (R)-1-(4-methoxyphenyl) propan-1-ol (2r) in enantiopure form using a biocatalyst on a gram scale. The whole cell catalyzed the reductions of ketone substrates on the preparative scale, demonstrating that W. paramesenteroides N7 would be a valuable biocatalyst for the preparation of chiral aromatic alcohols of pharmaceutical interest as a promising and alternative green approach.
AtıfScopus12WoS10OpenAlex11İncele - MakaleAçık Erişim2019Scopus SJRQ1Non-linear rheological (LAOS) behavior of sourdough-based dough
Yildirim-Mavis, Cigdem; Yilmaz, Mustafa Tahsin; Dertli, Enes; Arici, Muhammet; Ozmen, Duygu
During processing, wheat dough is known to undergo large deformation led by mixing and fermentation processes. This deformation is much more pronounced when sourdough is used in the recipe of wheat dough whose gluten is considerably hydrolyzed during sourdough fermentation. This causes deeper effects on rheological properties and shelf life of bakery products. Traditional small amplitude oscillatory tests do not enable us to comprehend the viscoelasticity under large deformations. In this respect, large amplitude oscillatory shear (LAOS) tests are useful for accurate characterization of the non-linear mechanical response. This study, therefore, is undertaken to investigate the non-linear mechanical response of dough prepared with different amounts of sourdough (0, 10, 20 30 and 40%) in a strain values ranging from 0.005 to 200% (frequency at 10 rad/s). As a result, sourdough was determined to have considerable effects on the non-linear viscoelastic response of dough. Strain-stiffening and shear-thinning behaviors were considerably influenced by sourdough incorporation and the dough started to show strain-softening and lowered shear-thinning behavior after giving a peak around at 100% strain due to the onset of the breakdown of the gluten network and suspension of starch matrix as consequence of the metabolic activity of the starter culture (Lactobacillus brevis E25) used in the preparation of sourdough. The physicochemical (pH and TTA), microbiological properties (LAB count) and extensographic properties were also shown to support the LAOS results. LAOS tests could be effectively and clearly used to reveal the effect of processing conditions (sourdough content and deformation by large strain amplitude) on the non-linear mechanical response of wheat dough.
AtıfScopus49WoS46OpenAlex46İncele - MakaleYalnız künye2019Scopus SJRQ1A novel perspective for Lactobacillus reuteri: Nanoencapsulation to obtain functional fish fillets
Ceylan, Z.; Uslu, Emin; İspirli, Hümeyra; Meral, Raciye; Gavgalı, Mehmet; 'Yilmaz, Mustafa Tahsin; Dertli, Enes
Enrichment of food products with beneficial Lactic Acid Bacteria (LAB) is an important methodology used to develop functional food products. Lactobacillus reuteri E81 was successfully nanoencapsulated into poly (vinyl alcohol)-based nanofibers for its application to the surface of fish fillets. The Scanning Electron Microscopy analysis confirmed the nanoencapsulation of L. reuteri E81 in electrospun nanofibers (LRNF) that had an average diameter of 381.83 ± 130.69 nm. LAB growth in rainbow trout fillets and fatty fish (mackerel) and were found to be 2.92 and in the range of 3.27 and 2.66 log CFU/g, respectively. Importantly, the antioxidative characteristics of fish fillets significantly increased following their coating with LRNF. The results revealed a significant increase in the inhibition of free radicals in the samples treated with nanoencapsulated L. reuteri as compared to control group fish fillet samples. DPPH activity significantly increased to 40.24%, 44.96%, 44.97 in mackerel samples treated with nanoencapsulated L. reuteri (MLR) and increased to 19.76%, 20.87%, 21.46% in rainbow samples treated with nanoencapsulated L. reuteri (RLR). MLR samples exhibited the highest ABTS radical-scavenging activity (1631 μmol TEAC/g). FRAP value of MLR samples was found to be 1.70 times higher than the control group samples.
AtıfScopus50WoS37OpenAlex45İncele - BildiriAçık Erişim2018Scopus SJRQ1Fabrication of propolis loaded electrosprayed nanoparticles
Özmen, Duygu; Karakas, Canan Yagmur; Yilmaz, Azime; Dertli, Enes; Bayram, Nesrin Ecem; Yilmaz, Mustafa Tahsin
AtıfWoS1OpenAlex1İncele - MakaleAçık Erişim2018Scopus SJRQ1Microbial species playing roles for the production of traditional Kasar cheese during pre-maturation period
Yuvaşen, Ayşe; Macit, Emine; Dertli, Enes
The microbial flora of traditional Kaşar cheese samples obtained from six dairy plants during pre-maturation period of Kaşar maturation was analysed. In total, 500 isolates of none-starter lactic acid bacteria (NSLAB) and 80 fungi isolates were isolated, and they were subjected to molecular discrimination by RAPD-PCR and rep-PCR analysis. Genotypic characterization of these isolates revealed the presence of 45 distinct strains belonging to 13 different NSLAB species with Lactobacillus paracasei as the dominant species. A rich yeast microflora in Kaşar samples was also observed with the presence of 19 distinct strains belonging to 8 different species with Pichia kudriavzevii as the dominant species. During this period, only two Penicillium species were found in Kaşar samples. This study confirmed the biodiversity of NSLAB and fungi microflora of Kaşar cheese during pre-maturation period, and these results are important for the development of starter cultures for Kaşar production at industrial level.
AtıfScopus18WoS14OpenAlex22İncele - MakaleAçık Erişim2018Scopus SJRQ1Structural analysis of the α-D-glucan produced by the sourdough isolate Lactobacillus brevis E25
Dertli, Enes; Colquhoun, Ian J.; Côté, Gregory L.; Le Gall, Gwénaëlle; Narbad, Arjan
Cereal-associated Lactic Acid Bacteria (LAB) are well known for homopolymeric exopolysaccharide (EPS) production. Herein, the structure of an EPS isolated from sourdough isolate Lactobacillus brevis E25 was determined. A modified BHI medium was used for production of EPS-E25 in order to eliminate potential contaminants. Analysis of sugar monomers in EPS revealed that glucose was the only sugar present. Structural characterisation of EPS by NMR and methylation analysis revealed that E25 produced a highly branched α-glucan with (α1 → 3) and (α1 → 6) glycosidic linkages, and was similar in structure to a previously reported EPS from Lactobacillus reuteri 180. The 1H and 13C NMR data were contrasted with newly recorded data for known polysaccharides (alternan, commercial dextran) which also contain α-(1,3,6)Glc branch points. It was found in both E25 EPS and alternan that NMR parameters could be used to distinguish glucose residues that had the same substitution pattern but occupied different positions in the structure.
AtıfScopus78WoS73OpenAlex80İncele - MakaleYalnız künye2018Scopus SJRQ3Identification of Lactic Acid Bacteria from Spontaneous Rye Sourdough and Determination of Their Functional Characteristics
Ispirli, Hümeyra; Demirbaş, Fatmanur; Yüzer, Mustafa O.; Dertli, Enes
This study aimed to identify Lactic Acid Bacteria (LAB) present in rye and rye bran sourdoughs that were prepared spontaneously and determine their functional characteristics. Genotypic characterization of the isolates revealed the presence of 15 distinct LAB strains belonging to 6 different species; Leuconostoc citreum, Lactobacillus plantarum, Lactobacillus graminis, Lactococcus lactis subsp. cremoris, Weissella confusa, and Weissella cibaria in rye sourdoughs. PCR screening of eps genes required for exopolysaccharide (EPS) production revealed that all strains possessed at least one gene required for EPS production and all strains produced homopolymeric EPS comprised of glucose or fructose two Lactobacillus plantarum strains produced both glucan and fructan type EPS. Antifungal activity of these strains was tested against Aspergillus niger and Penicillium chrysogenum identified in this study and several patterns were observed. The phytase activity of these strains was also determined and all strains showed phytase activity with varying degrees.
AtıfScopus24WoS15OpenAlex24İncele - MakaleAçık Erişim2018Scopus SJRQ1Glucan type exopolysaccharide (EPS) shows prebiotic effect and reduces syneresis in chocolate pudding
İspirli, Hümeyra; Demirbaş, Fatmanur; Dertli, Enes
Exopolysaccharides (EPS) of lactic acid bacteria are important biopolymers that can improve the physicochemical properties of food products and act as prebiotics. In this study the physicochemical role and the prebiotic effects of a glucan type EPS with (α1-3) and (α1-6) linkages were assessed in chocolate pudding containing Lactobacillus rhamnosus GG as a probiotic strain. The functions of EPS were determined by developing three different formulations: control, probiotic (Lactobacillus GG) and symbiotic pudding (Lactobacillus GG + EPS) samples. The pH and acidity of the symbiotic pudding sample were higher than the probiotic and the control samples during the 28-day of storage period. Similarly, an important level of increment in Lactobacillus GG levels in symbiotic sample was observed compared to the probiotic sample suggesting the prebiotic role of the α-glucan. Importantly, the syneresis in symbiotic pudding sample reduced significantly compared to other pudding samples which is related with the physicochemical role of glucan type EPS. This study reveals the prebiotic and physicochemical roles of α-glucan type EPS in a chocolate pudding model.
AtıfScopus33WoS28OpenAlex35İncele - MakaleAçık Erişim2018Scopus SJRQ3Genome sequences of five Lactobacillus sp. isolates from traditional Turkish sourdough
Dertli, Enes; Skory, Christopher D.; Şimşek, Ömer
A high level of variation in microflora can be observed in profiles of lactic acid bacteria (LAB) from sourdoughs. Here, we present draft genome sequences of Lactobacillus reuteri E81, L. reuteri LR5A, L. rhamnosus LR2, L. plantarum PFC-311, and the novel Lactobacillus sp. strain PFC-70, isolated from traditional Turkish backslopped wheat sourdoughs.
AtıfScopus8WoS8OpenAlex9İncele - MakaleAçık Erişim2018Scopus SJRQ2Isolation and characterisation of lactic acid bacteria from traditional koumiss and kurut
Ispirli, Hümeyra; Dertli, Enes
Lactic acid bacteria (LAB) were isolated from traditional koumiss and kurut samples and identification of these isolates revealed the presence of Lactobacillus fermentum, Enterococcus faecalis, Enterococcus durans, and Lactobacillus helveticus species. L. fermentum and L. helveticus strains were further tested for different characteristics. All tested strains produced heteropolymeric exopolysaccharides (EPS) with the presence of glucose and galactose as sugar monomers whereas three strains produced fructan type EPS as homopolymeric EPS. Important levels of antibacterial and antifungal activities were observed in these strains. All tested strains were sensitive to the antibiotics tested except streptomycin. Half of the tested strains showed important levels of survival ability under mimicking gastrointestinal conditions.
AtıfScopus20WoS14OpenAlex22İncele - MakaleAçık Erişim2018Scopus SJRQ2Synthesis of Enantiomerically Enriched Drug Precursors by Lactobacillus paracasei BD87E6 as a Biocatalyst
Öksüz, Selda; Şahin, Engin; Dertli, Enes
Global sales of single enantiomeric drug products are growing at an alarming rate every year. A total of 7 bacterial strains were screened for their ability to reduce acetophenones to its corresponding alcohol. Among these strains Lactobacillus paracasei BD87E6 was found to be the most successful biocatalyst to reduce the ketones to the corresponding alcohols. The reaction conditions were systematically optimized for the reducing agent Lactobacillus paracasei BD87E6, which showed high enantioselectivity and conversion for the bioreduction. The preparative scale asymmetric reduction of 3-methoxyacetophenone (1h) by Lactobacillus paracasei BD87E6 gave (R)-1-(3-methoxyphenyl)ethanol (2h) with 92% yield and 99% enantiomeric excess. Compound 2h could be used for the synthesis of (S)-rivastigmine which has a great potential for the treatment of Alzheimer's disease. This study demonstrates that Lactobacillus paracasei BD87E6 can be used as a biocatalyst to obtain chiral carbinol with excellent yield and selectivity. The whole cell catalyzed the reductions of ketone substrates on the preparative scale, demonstrating that Lactobacillus paracasei BD87E6 would be a valuable biocatalyst for the preparation of chiral aromatic alcohols of pharmaceutical interest.
AtıfScopus16WoS14OpenAlex15İncele - MakaleAçık Erişim2018Scopus SJRQ2Isolation and identification of exopolysaccharide producer lactic acid bacteria from Turkish yogurt
İspirli, Hümeyra; Dertli, Enes
Lactic acid bacteria (LAB) were isolated from traditional yogurt samples and genotypic characterization of these isolates revealed the presence of 21 distinct LAB strains belonging to Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, Leuconostoc mesenteroides, and Lactobacillus plantarum as new LAB strains. Determination of the exopolysaccharide (EPS) production characteristics of the selected strains of each species revealed that all strains possessed at least one gene required for both homopolymeric- and heteropolymeric-type EPS production. Structural analysis of the EPSs showed that L. delbrueckii subsp. bulgaricus Y39 and S. thermophilus Y102 produced heteropolymeric EPS containing glucose and galactose, whereas Leuc. mesenteroides Y35 and L. plantarum Y36 produced homopolymeric glucan-type EPS. The level of EPS production in these strains was found to be in a similar range. These strains with EPS production characteristics are good candidates for future studies as new LAB for yogurt production. Practical applications: Recent trends in yogurt production technology have led to an increased use of ropy starter cultures in yogurt production due to the technological roles of exopolysacharides (EPS) produced by these cultures. The main role of EPS in yogurt production is to improve the textural properties of yogurt as an in situ produced natural polymer. In addition to the yogurt starter cultures, use of adjunct cultures during production of yogurt is also of special interest to enhance the technological and nutritional characteristics of yogurt. Therefore, in this study, potential yogurt starter and adjunct cultures from traditional yogurt samples with EPS production characteristics were isolated. From these isolates, Lactobacillus delbrueckii subsp. bulgaricus Y39 and Streptococcus thermophilus Y102 produced heteropolymeric EPS containing glucose and galactose, whereas Leuconostoc mesenteroides Y35 and Lactobacillus plantarum Y36 produced homopolymeric glucan.
AtıfScopus33WoS27OpenAlex34İncele - MakaleAçık Erişim2018Scopus SJRQ1A novel strategy for probiotic bacteria: Ensuring microbial stability of fish fillets using characterized probiotic bacteria-loaded nanofibers
Ceylan, Zafer; Meral, Raciye; Karakaş, Canan Yağmur; Dertli, Enes; Yilmaz, Mustafa Tahsin
Nanoencapsulation of probiotic bacteria (L. rhamnosus) into poly(vinyl alcohol) & sodium alginate-based nanofibers (VSPBe) and also the production of poly(vinyl alcohol) & sodium alginate-based nanofibers (VS) were successfully obtained. VSPBe and VS nanofibers were used to limit the Total Mesophilic Aerobic Bacteria (TMABc), Psychrophilic Bacteria (TPBc) and also Yeast and Mold count (TYMc) growth in the fish fillet. Dispersion stability (ζ potential −6.29 mV and −7.74 mV, for VS and VSPBe, respectively), thermal decomposition (a reduction in mass of VS and VSPBe at temperatures 50 °C, corresponding to <5% and >5%, respectively) and morphological properties of nanofibers (diameters between 60 nm and 580 nm) were revealed by characterization analysis. Microbiological tests demonstrated that VS and VSPBe were effectively delayed the TMABc and TPBc growth in fish fillets up to 38%. However, the antimicrobial effects of nanofibers were not pronounced for TYM growth in the fish fillet. The viability of probiotic bacteria could be provided after electrospinning process and the use of L. rhamnosus-loaded nanofibers for delaying microbial growth in the fish fillets could be evaluated as a natural/novel technique.
AtıfScopus108WoS95OpenAlex108İncele - MakaleYalnız künye2017Optimization of Pectin Extraction from Orange Pulp and Characterization of Compositional and Steady Shear Properties
Yilmaz, Mustafa Tahsin; Muslu, Asli; Karasu, Salih; Bozkurt, Fatih; Dertli, Enes
Pectin, which is one of the most important wastes of fruit juice industry, was extracted from orange pulp at optimum conditions (pH, time and temperature) and modified using pectinase. The effect of modification on the structural properties of pectin was monitored using Fourier transformed infrared spectroscopy (FTIR) and high performance liquid chromatography (HPLC) analyses. The bands at 1600-1800 cm(-1) which indicate the specific region and quality of pectin were detected using FTIR while galacturonic acid content was determined using HPLC. The results showed that the galacturonic acid content of pectin from orange pulp was determined to be 406.44 mg/g powder pectin while that of the modified pectin from the orange pulp was determined to be 465,34 mg/g powder pectin. In addition, flow properties of the pectin samples were determined using rheological analysis. The viscosity and viscoelastic properties of the modified pectin samples were revealed to be different from those of non-modified pectin samples. The consistency index values of unmodified and modified pectin samples were determined to be 0.0559 Pa.s(n) and 0.0046 Pa.s(n), respectively.
AtıfWoS3İncele - BildiriAçık Erişim2017Scopus SJRQ1Nanoemulsion-based delivery systems to improve functionality of oregano essential oil: Molecular characterization and in vitro antifungal activity
Ermis, Ertan; Cicek, Perihan Kubra; Meral, Raciye; Yilmaz, Azime; Dertli, Enes; Yilmaz, Mustafa Tahsin
AtıfWoS1OpenAlex1İncele - MakaleYalnız künye2017Scopus SJRQ1Microbial diversity of traditional kefir grains and their role on kefir aroma
Dertli, Enes; Çon, Ahmet Hilmi
Kefir grains consist of rich bacterial and fungal microflora responsible for the production of this traditional fermented milk beverage with unique flavour properties. Here, a pyrosequencing approach was applied for the identification of microbial flora of four kefir grains collected from different regions of Turkey and the volatile compounds in kefir samples produced with these grains were determined. Lactobacillus kefiranofaciens presented in all grains at important levels and Enterobacter, Acinetobacter, Enterococcus and Pseudomonas spp. were observed in traditional kefir grains. The fungal microflora of kefir grains was dominated by yeast species and Dipodascaceae family was dominant and Saccharomyces cerevisiae presented in all grains. Other yeast species belonging to Kazachstania, Candida, Issatchenkia and Rhodotorula species were also detected in kefir grains. Volatile compounds of kefir samples were also diverse related to the microbial diversity of kefir grains. This study revealed the rich microflora of Turkish kefir grains and their interactions with the aromatic properties of kefir.
AtıfScopus143WoS130OpenAlex174İncele - MakaleYalnız künye2017Scopus SJRQ1Antimicrobial and functional properties of lactic acid bacteria isolated from sourdoughs
Demirbaş, Fatmanur; İspirli, Hümeyra; Kurnaz, Asena Ayşe; Yilmaz, Mustafa Tahsin; Dertli, Enes
The technological and functional properties of 15 LAB species previously isolated from sourdough were determined in terms of antifungal and antibacterial activities, production of GABA as a functional component and phytase activity. All sourdough isolates were capable of producing GABA and Weissella paramesenteroides N-7 and Lactobacillus paralimentarius E-106 showed the highest and the lowest production levels as 18,43 mM and 3,39 mM, respectively determined by HPLC analysis. The antifungal activity of these strains were tested against Aspergillus niger and Penicillium chrysogenum and two strains Lactobacillus paraplantarum N-15 and L. paralimentarius E-106 showed significant inhibitory effects to these mould species. Generally, different levels of antibacterial activity of these species were observed against food-borne pathogens but only one strain showed low levels of inhibitory effect to Salmonella typhimurium but not the other strains. The PCR detection of several bacteriocin coding genes revealed that all strains were harboured at least one bacteriocin gene among the tested genes. Finally, all strains showed phytase activity but these activity was dependant on strain specific conditions. This study revealed some important techno-functional properties of sourdough LAB strains which can play crucial roles on sourdough technology.
AtıfScopus73WoS60OpenAlex68İncele