Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2026Scopus SJRQ1Optimization of surface modification parameters of calcium carbonate in the rotary-vibration mill with a fuzzy-based taguchi experimental method
Özdemir, Akın; Uçurum, Metin
Ultra-fine calcium carbonate (UCC) is used as a filler material in polymers, and after a surface modification (coating) process, its surface changes from hydrophilic to hydrophobic. However, conventional coating techniques such as raymond and pin mills are widely used in the industry; there is still a need for new, inexpensive, and practical methods. Mechanochemical technologies are considered one of the most effective alternatives. The rotary-vibration mill (RVM) works mechanically and is characterized by low investment and operating costs. There are three main contributions in this paper. First, a fuzzy-based Taguchi experimental design is proposed to analyze a fuzzy response under uncertainty. Second, the surface modification of UCC with stearic acid was carried out using RMV, with five modification parameters and an active ratio fuzzy response. Moreover, the results indicate that RVMs are an alternative mechanochemical surface modification technology for preparing coated calcium carbonate (CCC). Finally, particle size distribution (PSD), contact angle, XRD (X-Ray Diffraction Analysis), TGA-DTA (Thermogravimetric Analysis-Differential Thermal Analysis), FTIR (Fourier Transform Infrared Spectrophotometer), and SEM (Scanning Electron Microscopy) analyses were conducted for the coated calcium carbonate (CCC) acquired from the optimum conditions of the modification study.
- MakaleYalnız künye2026Scopus SJRQ2Assessment of municipal water quality criteria in consideration of microbiological and physicochemical parameters using a fuzzy decision-making framework
Suiçmez, Özlem; Teke, Çağatay; Özdemir, Akın
Water is a significant element for the sustainability of life and is crucial for many aspects, such as agriculture, cities, ecosystems, industries, and people. This study focuses on municipal water quality assessments for urbanization activities and human health concerns when dealing with the sustainable city concept. For the first time, an integrated fuzzy decision-making framework is proposed to evaluate municipal water quality criteria with microbiological parameters, heavy metals, and other chemicals. For this aim, the eight main criteria and forty-four sub-criteria were specified to evaluate municipal water quality for a sustainable city. A case study was performed in Bayburt, Türkiye, to evaluate 130 water depots when dealing with a number of scenarios. Moreover, the Sustainable Development Goals (SDGs) 6.1 and 6.3 can be achieved through the study. Finally, this study presents how to develop safe and clean water management for the concept of a sustainable city.
- MakaleYalnız künye2025Scopus SJRQ1Optimization of surface modification parameters of fly ash with high calcium oxide (CaO) content to use as a filling material
Uçurum, Metin; Özdemir, Akın; Teke, Çağatay
Fly ash (FA) is the fine-grained waste product obtained by burning coal after being ground to specific sizes in thermal power plants, carried with flue gases, and kept in cyclones or electro-filters. Like every industrial waste, the possibilities of utilizing FA have been investigated, and it can be utilized as an additive in cement and concrete. Despite this, industrial waste, which increases daily in the world, brings many problems, especially environmental problems. For this reason, alternative usage areas of the waste in question are constantly being investigated. In this paper, FA containing approximately 50 % CaO from Afşin-Elbistan, Turkiye was processed with stearic acid in a planetary mill to be used as a filling material in industrial products, and it has a grain size of 68.10 μm on a d50 basis, a specific surface area (SSA) of 176.40 m2/g and a contact angle of 13.89. An optimization and characterization study was conducted to make the hydrophilic surface structure hydrophobic by mechanochemical surface modification. Also, surface modification parameters, such as operational speed (rpm), ball filling ratio (%), FA filling ratio (%), pulp density, stearic acid dosage (% of FA), and modification time (min.) were optimized with the D-optimal experimental design. Based on the optimum surface modification parameters, a coated fly ash (CFA) product was obtained with an active ratio of 99.70 %, a contact angle of 95.06o, a medium size (d50) size of 10.60 μm, and an SSA of 926.90 m2/g.
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İncele - 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.
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İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ1Wet mechanochemical surface modification of calcite employing an integration of conventional design and analytical hierarchy process
Uçurum, Metin; Özdemir, Akın
The demand for ultra-fine mineral powders from various industries requires the applications of wet grinding and surface modification. In this study, wet mechanochemical surface modification of micronized calcite (d50 = 4.92 μm) with stearic acid [CH3(CH2)16COOH] was carried out in a planetary ball mill. The seven parameters were specified: ball filling ratio (%), ball size distribution ratio (10 and 15 mm, %), micronized calcite filling ratio (%), pulp solid ratio (wt%), mill speed (rpm), stearic acid dosage (% of micronized calcite) and modification time (min). Then, these parameters were optimized using a conventional experimental design when maximizing the active ratio (%) as a significant value for coated calcite. Besides, the analytical hierarchy process was applied to observe the importance of each parameter. Stearic acid dosage, mill speed, and micronized calcite filling ratio are the top three parameters affecting the active ratio. Next, size distribution, XRF, XRD, SEM, FTIR, TGA-DTA, contact angle, and whiteness measurements were performed on the micronized calcite (MC) and coated micronized calcite (CMC) samples. The final CMC product had a 99.90% active ratio, 2.49 μm mean (d50) particle size, and 101.66o contact angle. Finally, CMC obtained by the surface modification can be used as a filler mineral.
AtıfScopus6WoS4OpenAlex7İncele - MakaleAçık Erişim2024Scopus SJRQ1Efficient bioreduction of 4-phenyl-2-butanone to drug precursor (S)-4-phenyl-2-butanol by a whole-cell biocatalyst using a novel hybrid design technique
Bayhan, Beyzanur; Özdemir, Akın; Dertli, Enes; Şahin, Engin
Asymmetric synthesis is a critical tactic in pharmaceutical industries for creating chiral medications as it allows an enantiomer to be obtained in synthetic chemistry. The asymmetric bioreduction processes by biocatalysts have shown significant potential in producing chiral alcohols. The amount of substrate and the production method of the biocatalytic synthesis of (S)-4-phenyl-2-butanol ((S)-2) are not still desired levels. Furthermore, the biocatalytic asymmetric reduction of 4-phenyl-2-butanone (1) to (R)- or (S)-4-phenyl-2-butanol did not use any mathematical modeling techniques. In this study, the asymmetric bioreduction of 1 was carried out in this work employing Lactobacillus paracasei BD71 biocatalyst and a novel hybrid design-based optimization approach. By using the hybrid design technique, the optimal circumstances were discovered to be pH = 7, temperature = 29 °C, incubation period = 66 h, and agitation speed = 189 rpm. Also, the enantiomeric excess (ee) and conversion could be 99.15 % and 98.19 %, respectively. Next, (S)-2 was acquired to be ee: 99 %, conversion: >99 %, and yield: 97 % from the optimum bioreduction conditions. Furthermore, 14.08 g of 1 under optimal conditions was entirely transformed into (S)-2 (13.84 g, 97 % isolated yield). This study is the first research attempt to use a biocatalyst and an innovative and new hybrid design-based optimization approach to fabricate enantiopure (S)-2 at a high gram scale. This work has successfully demonstrated that the new hybrid design-based optimization technique is applicable to biocatalytic asymmetric reduction processes.
AtıfScopus9WoS8OpenAlex5İncele - MakaleAçık Erişim2024Scopus SJRQ1A Multi-response Nonlinear Programming Model with an Inscribed Design to Optimize Bioreduction Conditions of (S)-phenyl (pyridin-2-yl)methanol by Leuconostoc pseudomesenteroides N13
Özdemir, Akın; Şahin, Engin
Asymmetric bioreductions have the potential to synthesize chiral alcohols when catalyzed by biocatalysts. Nevertheless, the (S)-phenyl (pyridin-2-yl)methanol ((S)-2) analgesic synthesis poses significant challenges concerning unsatisfactory substrate amount and production method. Thus, this study proposes an inscribed design-focused multi-response nonlinear optimization model for the asymmetric reduction of the phenyl(pyridin-2-yl)methanone (1) with Leuconostoc pseudomesenteroides N13 biocatalyst. From the novel inscribed design-focused multi-response nonlinear optimization model, optimization conditions of the reaction, such as pH = 6, temperature = 29 °C, incubation time = 53 h, and agitation speed = 153 rpm, were found. Also, the reaction conversion was predicted to be 99%, and the product of the enantiomeric excess (ee) was 98.4% under the obtained optimization conditions. (S)-2 was obtained with 99% ee, 99% conversion, and 98% yield while performing a validation experiment using the determined optimized conditions. In addition, 1 with the amount of 11.9 g was converted entirely to (S)-2 (11.79 g, 98% isolated yield) on a high gram scale. Also, this study is noted as the first example of the gram-scale production of (S)-2 using an optimization strategy and biocatalyst. Further, the applicability of the inscribed design-focused optimization model in biocatalytic reactions has been demonstrated and provides an effective process for the analgesic synthesis of (S)-2, which is a green, cost-effective method of producing chiral aryl heteroaryl methanol.
AtıfScopus3WoS3OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ1Optimization of mechanochemical surface modification parameters on planetary mill using an I-optimal experimental design
Özdemir, Akın; Uçurum, Metin
Several micro-particle-size additives and filler minerals are added to many industrial products, especially plastic, in order to reduce cost and improve mechanical properties and appearance. Also, grinding and surface modification are two fundamental properties of the filler minerals used in plastic products. Notably, Bayburt stone (BS) used as a natural raw material from Bayburt, Türkiye contains 76% SiO2 and 15% Al2O3. In this paper, the hydrophilic surface structure of micronized Bayburt stone (MBS) was made hydrophobe by mechanochemical surface modification using calcium stearate [Ca(C17H35COO)2] in a laboratory-type planetary mill. Next, the optimum conditions of the surface modification design factors, which are (1) ball filling ratio = 30.53%, (2) powder filling ratio = 10.43%, (3) mill speed = 475.91 rpm, (4) chemical dosage = 1.99% of powder, and (5) modification time = 4.83 min., were obtained using the proposed I-optimal design-focused optimization model when predicting the model parameters. In addition, a coated micronized Bayburt stone (CMBS) product with an active ratio (AR) of 99.90% and d10, d50, and d90 values of 1.32 μm, 3.48 μm and 9.55 μm were achieved. Finally, particle size distribution (PSD), thermo-gravimetric and differential thermal analyzer (TG-DTA), Fourier transform infrared (FTIR), scanning electron microscope (SEM), electron dispersive spectrum (EDS), and contact angle analyses were performed on the CMBS product.
AtıfScopus5WoS6OpenAlex6İncele - MakaleYalnız künye2024Scopus SJRQ1A Novel Fuzzy Cumulative Sum Control Chart with an α-Level Cut Based on Trapezoidal Fuzzy Numbers for a Real Case Application
Özdemir, Akın; Uçurum, Metin; Serencam, Hüseyin
Statistical process control (SPC) is widely used to monitor production processes in many industries under certain conditions. When dealing with a quality characteristic for uncertainty, fuzzy numbers are used in the context of the statistical process control (SPC) to monitor a fuzzy production process. The aim of this paper is fourfold. One, a fuzzy X¯-R control chart with an α-level cut is used based on trapezoidal fuzzy numbers (TFNs) for detecting the large shifts in the fuzzy process mean. Second, a fuzzy cumulative sum (FCUSUM) control with an α-level cut based on TFNs is firstly developed for detecting the small shifts in the fuzzy process mean. Third, the fuzzy process capability indices (FPCIs) are presented to measure the fuzzy process performance. Finally, an ultra-fine calcite production process is controlled with both the fuzzy X¯-R control chart and the proposed FCUSUM control chart. The results of the fuzzy X¯-R control charts show that the fuzzy production process is in control, and large shifts in the fuzzy process mean were detected. On the other hand, the results of the FCUSUM charts show that the fuzzy production process is out of control, and small shifts in the fuzzy process mean were detected. FPCIs are also conducted, and the results of fuzzy Cpk indices show that the ultra-fine calcite production process is not capable of meeting specification limits.
AtıfScopus7WoS9OpenAlex9İncele - MakaleYalnız künye2024Scopus SJRQ1Effective biocatalytic synthesis of enentiopure (R)-1,2-diphenylethanol as a pharmaceutical precursor using whole-cell biocatalyst
Çakmak, Fadile; Özdemir, Akın; Dertli, Enes; Şahin, Engin
Optically active alcohols are crucial precursors. 1,2-Diarylethanols and their analogues constitute a significant group of substances of biological significance. The biocatalytic synthesis of (R)-1,2-diphenylethanol ((R)-2), which can be utilized as a precursor to important drugs, is still not at the desired level in terms of substrate amount and production process. This study asymmetrically reduced 1,2-diphenylethanone (1) using the Lactobacillus paracasei BD87E6 biocatalyst and a novel orthogonal quadratic design-embedded optimization approach. The following reaction optimization conditions were determined using the suggested optimization technique: pH = 6, temperature = 31 °C, incubation period = 48 h, and agitation speed=134 rpm. In addition, the reaction conversion was estimated to be 99.38 %, and the product's enantiomeric excess (ee) was estimated to be 99.12 %. Further, (R)-2 was produced with >99 % ee, >99 % conversion, and 98 % yield in the experimental investigation under the established optimum conditions. This study is the first attempt to reduce substrate 1 to (R) or (S)-2 using a mathematical optimization method in the presence of a biocatalyst. Furthermore, on a high-gram scale, 1 (15.70 g) was entirely transformed into (R)-2 (15.54 g, 98 % isolated yield). Notably, this study is also the first to perform the gram-scale production of (R)-2 using a novel optimization approach and a biocatalyst. Finally, the innovative and novel orthogonal quadratic design-embedded optimization technique has been demonstrated as an efficient, cost-effective, and environmentally friendly biocatalytic procedure for synthesizing (R)-2.
AtıfScopus7WoS7OpenAlex6İncele - MakaleYalnız künye2023Scopus SJRQ3Modified distance optimization method for the asymmetric bioreduction conditions of phenyl(thiophen-2-yl)methanone by Weissella paramesenteroides N7
Özdemir, Akın; Şahin, Engin
Chirality plays a significant part in life since it is closely linked to carrying out the many metabolic processes that make up a living being. Chiral secondary alcohols such as diaryl-, aryl heteroaryl-, and diheteroaryl are employed in pharmaceuticals as drug intermediates. Although biocatalytic asymmetric reduction of prochiral ketones containing aromatic and heteroaromatic groups is widely known, biocatalytic reduction of heteroaromatic prochiral ketones containing sulfur heteroatoms is rarely known. Very few studies exist in the literature, including the biocatalytic reduction of phenyl(thiophen-2-yl)methanone (1). Moreover, the biocatalytic reduction of 1 with a mathematical modelling and optimization technique is unknown until now. In this study, Weissella paramesenteroides N7 biocatalyst for the asymmetric bioreduction of 1 using a novel modified distance optimization method. Optimization conditions were found as pH = 6.46, temperature = 26 °C, incubation period = 71 h, agitation speed = 200 rpm by the modified distance optimization method, and it was determined that the conversion and enantiomeric excess (ee) under these conditions could be 98.7% and 98%, respectively. Under these proposed optimization conditions, (S)-phenyl(thiophen-2-yl)methanol ((S)-2) was obtained with >99% ee, >99% conversion, and 97% yield. In addition, 11.29 g of 1 was completely converted into (S)-2 (11.07 g, 97% isolated yield) under optimized conditions. This is the first report about the fabrication of enantiopure (S)-2 in high gram scale using a biocatalyst and a novel modified distance optimization technique. In this study, the successful applicability of the new modified distance optimization method in biocatalytic asymmetric reduction reactions has been successfully demonstrated.
AtıfScopus3WoS3OpenAlex5İncele - MakaleAçık Erişim2023Scopus SJRQ2Efficient bio-catalytic production of enentiopure (S)-(4-chlorophenyl)(phenyl)methanol as a drug precursor by using a novel rotatable composite design-based optimization strategy
Tozlu, Nesrullah; Bülbül, Ali Savaş; Özdemir, Akın; Şahin, Engin
Asymmetric bioreductions catalyzed by biocatalysts have demonstrated great promise in manufacturing chiral alcohols. On the other hand, the synthesis of (S)-(4-chlorophenyl)(phenyl)methanol ((S)-2), precursors of L-cloprastine and carbinoxamine, still presents considerable challenges due to the inadequate substrate quantity and production process. In this work, a novel rotatable composite design-based optimization technique was used with the Lactobacillus paracasei BD101 biocatalyst for the asymmetric reduction of (4-chlorophenyl)(phenyl)methanone (1). Optimization conditions of the reaction were determined by the proposed optimization strategy as: pH=5.85, temperature=37 °C, incubation time=71 h, and agitation speed=120 rpm. The reaction conversion and the product of enantiomeric excess (ee) were also predicted to be 97% and 99%, respectively. In the experimental study performed under the determined optimized conditions, (S)-2 was obtained with >99% ee, >99% conversion, and 97% yield. In addition, 1 with the amount of 15.166 g was completely converted to (S)-2 (14.85 g, 97% isolated yield) on a high-gram scale. Notice that the manufacture of (S)-2 on a gram scale utilizing a biocatalyst and an optimization technique is demonstrated in this work for the first time. Finally, an economical, effective, and environmentally friendly biocatalytic process for the biocatalytic synthesis of (S)-2, which have antitussive and antiemetic properties and relax the bronchial muscle, has been demonstrated by the novel rotatable composite design-based optimization method.
AtıfScopus3WoS3OpenAlex2İncele - 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 SJRQ2Efficient bioreduction of cyclohexyl phenyl ketone by Leuconostoc pseudomesenteroides N13 biocatalyst using a distance-based design-focused optimization model
Özdemir, Akın; Şahin, Engin
Whole-cell biocatalysts have been a popular method for the preparation of chiral alcohols. Although asymmetric reduction of cyclohexyl(phenyl)methanone (1) by chemical catalysts is common, a biocatalytic asymmetric reduction is extremely rare. In this respect, we report herein that Leuconostoc pseudomesenteroides N13 was successfully employed as a biocatalyst to reduce 1 to (S)-cyclohexyl(phenyl)methanol ((S)-2). Furthermore, the use of a mathematical optimization strategy for asymmetric reduction of substrate 1 is not known in the current literature. The new distance-based design-focused optimization model was used to enhance the conversion of the substrate, enantiomeric excess (ee) of product, and yield. The distance-based design-focused optimization model identified the following optimal bioreduction conditions: pH=6.46, temperature=30°C, incubation period=72 hours, and agitation speed=199 rpm. Then it was stated that under these ideal conditions, (S)-2 may be produced with 99 % ee and 98.46 % conversion rate (cr). (S)-2 was achieved with 99% ee, and 99% cr as a consequence of the experimental reaction carried out under the indicated optimization conditions. It has been shown that Leuconostoc pseudomesenteroides N13 can be utilized as a biocatalyst in asymmetric reduction reactions. This study, in addition to being the first example of a bioreduction of substrate 1 by mathematical optimization, also demonstrates for the first time the distance-based design-focused model can be used in the bioreduction reaction.
AtıfScopus9WoS9OpenAlex8İncele - MakaleAçık Erişim2022Scopus SJRQ1Optimization of Asymmetric Bioreduction Conditions of 2-methyl-1-phenylpropan-1-one by Lactobacillus fermentum BY35 Using I-Optimal Design-Based Model
Aksuoğlu, Selmani; Özdemir, Akın; Serencam, Hüseyin; Dertli, Enes; Şahin, Engin
The bioreduction of prochiral ketones offers efficient access to chiral secondary alcohols, which are potentially beneficial precursors for producing many biologically active compounds and natural products. This bioreduction process can be affected by different parameters when whole-cell of biocatalysts such as Lactic Acid Bacteria strains are applied. In this context, this paper proposed an I-optimal design-based model to optimize culture parameters such as temperature, pH, incubation period, and agitation speed for asymmetric bioreduction of 2-methyl-1-phenylpropan-1-one (1) with Lactobacillus fermentum BY35 as a biocatalyst while achieving the highest conversion rate (cr) and enantiomeric excess (ee). The optimum settings of the four culture parameters and the cr and ee values were found using the proposed optimization model as follows: pH = 6.5, temperature = 25 °C, incubation period = 38.5 h, agitation speed = 200 rpm, the ee value = 98.78%, and the cr value = 98.92%. After the validation of the process, the cr and ee values were found to be > 99% and > 99%, respectively, while using the optimum operating conditions from the optimization model. Thus, the results of the optimization model are consistent with the results of the validation experiment. It is also noted that this paper is the first to optimize culture parameters using the proposed I-optimal design-based model for an asymmetric reduction.
AtıfScopus3WoS3OpenAlex3İncele - MakaleYalnız künye2022Scopus SJRQ3Optimization of asymmetric reduction conditions of 2-bromo-1-(naphthalen-2-yl)ethanone by Enterococcus faecium BY48 biocatalyst with A-optimal design-embedded model
Özdemir, Akın; Şahin, Engin
Aromatic α-halohydrins, especially 2-haloethanols, which are a common pharmacological precursor, may be readily transformed to chiral β-adrenergic receptor blockers. Studies including the synthesis of (S)-2-bromo-1-(naphthalen-2-yl)ethanol ((S)-2), an α-halohydrin, in high conversion, enantiomeric excess (ee), and yield by biocatalytic asymmetric reduction of 2-bromo-1-(naphthalen-2-yl)ethanone (1) are still insufficient. Moreover, asymmetric reduction of substrate 1 using a mathematical optimization method is not explored in the current literature. In this article, the four asymmetric bioreduction conditions, which are (1) pH, (2) temperature, (3) incubation period, and (4) agitation speed, of substrate 1 were optimized to obtain (S)-2 with A-optimal design-embedded model in the presence of Enterococcus faecium BY48. Optimum bioreduction conditions were determined by the A-optimal design-embedded model as follows: pH = 7, temperature = 25°C, incubation period = 24 h, and agitation speed = 200 rpm. And then, it was suggested that (S)-2 could be obtained with 98.88% ee and 100% conversion rate (cr) under these optimum conditions. As a result of the experimental reaction performed under the optimization conditions suggested by the model, (S)-2 was obtained with 99% ee and 100% cr. The study revealed that E. faecium BY48 could be used as a biocatalyst in asymmetric reduction reactions. Also, the A-optimal design-embedded model could have the great potential to obtain the optimum asymmetric bioreduction conditions.
AtıfScopus3WoS3OpenAlex4İncele - MakaleAçık Erişim2022Scopus SJRQ1Optimization of Biocatalytic Production of Enantiopure (S)-1-(4-Methoxyphenyl) Ethanol with Lactobacillus senmaizuke Using the Box–Behnken Design-Based Model
Kavi, Mervenur; Özdemir, Akın; Dertli, Enes; Şahin, Engin
Enantiomerically pure (S)-1-(4-methoxyphenyl) ethanol is a significant molecule for the production of various drug intermediates. (S)-1-(4-methoxyphenyl) ethanol was synthesized from 4-methoxyacetophenone using Lactobacillus senmaizuke as a biocatalyst. In addition, optimization of experimental conditions is important to analyze the role of culture parameters for catalytic bioreduction reactions. For this particular purpose, the experimental conditions of pH, incubation period, temperature, and agitation speed were investigated with the Box–Behnken experimental design-based proposed optimization model. (S)-1-(4-methoxyphenyl) ethanol, which can be used for the synthesis of antihistamines, including diphenhydramine hydrochloride and loratadine cycloalkyl [b] indoles that have the treatment function for an allergic response, was obtained in > 99% conversion, > 99% enantiomeric excess and 96% yield with whole cells of L. senmaizukei at this optimization conditions: pH = 5.80, the temperature = 29 °C, incubation period = 50 h, and agitation speed = 155 rpm. The bioreduction of 4-methoxyacetophenone efficiency was importantly affected by the quadratic and linear effects of experimental design parameters. Besides, the results demonstrate the importance of design parameters for catalytic bioreduction reactions. It is also concluded that the results show the effectiveness of the Box–Behnken experimental design-based proposed model to obtain optimum operating conditions of design parameters for catalytic bioreduction reactions.
AtıfScopus4WoS4OpenAlex4İncele - MakaleYalnız künye2022Scopus SJRQ3Optimization of asymmetric reduction conditions of 1-(benzo [d] [1,3] dioxol-5-yl) ethanone by Lactobacillus fermentum P1 using D-optimal experimental design-based model
Özdemir, Akın; Dertli, Enes; Şahin, Engin
The biocatalytic asymmetric reduction of prochiral ketones is a significant transformation in organic chemistry as chiral carbinols are biologically active molecules and may be used as precursors of many drugs. In this study, the bioreduction of 1-(benzo [d] [1,3] dioxol-5-yl) ethanone for the production of enantiomerically pure (S)-1-(1,3-benzodioxal-5-yl) ethanol was investigated using freeze-dried whole-cell of Lactobacillus fermentum P1 and the reduction conditions was optimized with a D-optimal experimental design-based optimization methodology. This is the first study using this optimization methodology in a biocatalytic asymmetric reduction. Using D-optimal experimental design-based optimization, optimum reaction conditions were predicted as pH 6.20, temperature 30 °C, incubation time 30 h, and agitation speed 193 rpm. For these operating conditions, it was estimated that the product could be obtained with 94% enantiomeric excess (ee) and 95% conversion rate (cr). Besides, the actual ee and cr were found to be 99% tested under optimized reaction conditions. These findings demonstrated that L. fermentum P1 as an effective biocatalyst to obtain (S)-1-(1,3-benzodioxal-5-yl) ethanol and with the D-optimal experimental design-based optimization, this product could be obtained with the 99% ee and 99% cr. Finally, the proposed mathematical optimization technique showed the applicability of the obtained results for asymmetric reduction reactions.
AtıfScopus6WoS6OpenAlex7İncele - MakaleAçık Erişim2021Scopus SJRQ1Development of a Fuzzy Exponentially Weighted Moving Average Control Chart with an α-level Cut for Monitoring a Production Process
Kaplan Göztok, Kader; Uçurum, Metin; Özdemir, Akın
Statistical quality control is a useful approach that applies to statistical techniques for monitoring a production system. These charts are effective to monitor the process under certain conditions. On the other hand, the fuzzy set theory is an appropriate tool to deal with an uncertain situation. This paper is fourfold. First of all, triangular fuzzy numbers with an α-level cut technique are used for each sample. The α-level cut technique is sensitive to satisfy the process requirement. Second, a fuzzy exponentially weighted moving average (FEWMA) control chart is proposed with the α-level cut technique. The proposed FEWMA detects small shifts under uncertain situations while using a unity technique for samples. Third, the fuzzy target-focused process capability index (FCpm) index is proposed to measure the fuzzy process performance. Then, a case study is presented to monitor a pumice block plant using the FEWMA control chart with the α-level cut and measure the process performance with the FCpm index. Comparative studies are also presented. By using the proposed FEWMA control chart with the α-level cut, the accuracy and the flexibility of control specification limits are reported for the case study.
AtıfScopus9WoS8OpenAlex7İncele - MakaleAçık Erişim2021Scopus SJRQ3A novel approach to finding optimum operating conditions of design factors for the grinding experiment
Uçurum, Metin; Özdemir, Akın; Teke, Çağatay; Tekin, İlker
The efficiency of grinding experiments is an important issue for many industries. In this paper, a central composite design-based methodology was proposed to investigate the four design factors that affect the particle sizes. The four design factors were specified as mill speed (% of Nc), ball filling ratio (fc), powder filling ratio (jb) and grinding time (min). Another important issue was how to obtain an optimum operating condition for four design factors. For this particular purpose, a novel dual response optimization model was proposed using the particle sizes (d 10, d 50, and d 90) and the span value concept. This proposed approach was compared to the desirability function-based optimization concept. The verification study of the experiment was also carried out. The results of the grinding experiment runs showed that the optimum operating conditions were mill speed 73.495% of Nc, ball filling ratio 0.354, powder filling ratio 0.157, and grinding time 70 min. In addition, d 10, d 50, and d 90 were found 3.31 µm, 12µm, and 45.6 µm, respectively. The span value was also found at 3.52.
AtıfScopus3WoS3OpenAlex4İncele