Gümüşhane üniversitesi fen bilimleri enstitüsü dergisi, Apr 15, 2021
Nanoparticles (NP), which can be produced for many different fields and purposes; are at size var... more Nanoparticles (NP), which can be produced for many different fields and purposes; are at size vary from nanometer to a micrometer. These particles can be prepared by different approaches such as chemical, physical and biological methods. However, the biological approach is the most promising approach among other methods due to its simplicity and environmentally friendly conditions. The production of the nanoparticle by means of a biological approach does not require any high temperature, acidic/basic conditions and hazardous chemicals. Therefore, this method is named "green synthesis". Development in microtechnology has had profound effects in many areas such as drug discovery, biology, diagnosis, and tissue engineering. Microfluidics which focuses on the processing of liquids in microscale systems has attracted wide attention in the production process of nanoparticles due to precise control and fast mixing. The main purpose of this study is to produce and characterize metal nanoparticles by combining microsystems and green synthesis approaches. For this purpose, in the first step, the design of microsystems that suitable for the flow of different phases was performed. In the second step, ZnO nanoparticle synthesis was carried out using the red cabbage (Brassica oleracea var.capitata f. Rubra) extracts. The synthesis of nanoparticles achieved by optimizing different parameters such as; extract: zinc ratio, zinc solution concentration, flow rates, and flow rates ratio in the microsystem and temperature. The results showed that the herbal red cabbage components can be used for the green synthesis of ZnO nanoparticles.
Bu calismada, Rubia tinctorum L. callus ve hucre suspansiyon kulturlerine 100 mM ve 200 mM konsan... more Bu calismada, Rubia tinctorum L. callus ve hucre suspansiyon kulturlerine 100 mM ve 200 mM konsantrasyonlarda tuz stresi uygulanarak elde edilen biyokutlelerdeki yas ve kuru agirliklar (g), bagil kuru agirlik oranlari (mg/g kuru agirlik) ve alizarin ve purpurin icerikleri uzerine etkileri belirlenmistir. Tuz consantrasyonundaki artisa bagli olarak, callus ve hucre suspansiyon kulturlerinden elde edilen biyokutle azalmistir. Kallus kulturlerindeki hucrelerde dusuk canlilik ve cogalma oranina ragmen, biyokutle belirgin bir dusus gostermemistir. Kallus kulturlerinde tuz konsantrasyonu arttikca alizarin ve purpurin icerigi azalmistir, ancak bu bilesiklerin miktari hucre suspansiyon kulturlerinde artmistir. Yapilan denemelerde inokulasyon oranlarinin yas ve kuru agirlik miktari ve alizarin ve purpurin icerigi uzerine etkili oldugu tespit edilmistir. Hucre suspansiyon kulturlerinde 1:2 inokulasyon orani daha yuksek alizarin ve purpurin icerigi saglarken, 1:4 inokusyon oraninda biyokutle miktari daha fazladir. En yuksek alizarin ( 3.183 mg/g) ve purpurin ( 1.153 mg/g) icerikleri 1:2 inokulasyon oraninda ve 200 mM NaCl iceren besin ortamindan tespit edilmistir.
ABSTRACT Aims of this study were to isolate endophytes from different parts of hazelnut – Corylus... more ABSTRACT Aims of this study were to isolate endophytes from different parts of hazelnut – Corylus avellana L. to obtain bioactive secondary metabolites and search for the presence of gene region of taxadiene synthase (Ts), a key enzyme in taxol biosynthesis, on selected fungi. Fourteen fungal species were isolated and cultured for the screening studies. The cell-free fermentation broths were extracted with chloroform. The chloroform extracts were tested for cytotoxic activity by MTT method. Based on the activity results and chemical profiles, the isolate identified as Phomopsis amygdali by internal transcribed spaces (ITS) sequence analysis using ITS1 primer was selected for further studies. After large-scale fermentation and purification studies, two major compounds, one of which turned out to be a new secondary metabolite, were isolated and characterized. Structure of the new metabolite was elucidated as (S)-4-butoxy-6-((S)-1-hydroxypentyl)-5,6-dihydro-2H-pyran-2-one by the extensive use of 1D and 2D NMR, and HR-MS, whereas the known compound was identified as (−)pestalotin. Additionally, to evaluate taxol-producing potential of the selected isolate, a PCR amplification study followed by gel electrophoresis analysis was carried out revealing no Ts gene region.
Plant Cell, Tissue and Organ Culture (PCTOC), 2012
There was a typing error in the second author's first name in the original publication. The name ... more There was a typing error in the second author's first name in the original publication. The name shown in this erratum is correct.
2018 IEEE Micro Electro Mechanical Systems (MEMS), 2018
In this paper, we demonstrate the dipstick-based digitisation and detection of bacterial sample o... more In this paper, we demonstrate the dipstick-based digitisation and detection of bacterial sample of concentration down to 103 CFU/ml. The significance of this work is that we are able to detect concentrations of bacteria relevant for urinary tract infection (UTI) with minimal handling time and without the need for complicated external equipment.
The aim of this study was to formulate silica and alginate hydrogels for immobilization of β-gluc... more The aim of this study was to formulate silica and alginate hydrogels for immobilization of β-glucosidase. For this purpose, enzyme kinetics in hydrogels were determined, activity of immobilized enzymes was compared with that of free enzyme, and structures of silica and alginate hydrogels were characterized in terms of surface area and pore size. The addition of polyethylene oxide improved the mechanical strength of the silica gels and 68% of the initial activity of the enzyme was preserved after immobilizing into tetraethyl orthosilicate-polyethylene oxide matrix where the relative activity in alginate beads was 87%. The immobilized β-glucosidase was loaded into glass-silicon-glass microreactors and catalysis of 4-nitrophenyl β-d-glucopyranoside was carried out at various retention times (5, 10, and 15 min) to compare the performance of silica and alginate hydrogels as immobilization matrices. The results indicated that alginate hydrogels exhibited slightly better properties than silica, which can be utilized for biocatalysis in microfluidic platforms.
The objective of this study was to develop an injectable alginate based formulation for immobiliz... more The objective of this study was to develop an injectable alginate based formulation for immobilizing enzymes into microfluidic systems. The gelation was induced upon lowering the pH by addition of d-glucono-δ-lactone (GDL) and release of Ca(+) ions from solid CaCO3. The effects of GDL concentration on enzymatic activity and gelation time were investigated. The results indicated that increasing the GDL concentration increased both surface area and enzymatic activity. Also, chitosan was added to the formulation at different ratios to enhance the stability of enzyme during immobilization. For microfluidic application, 100μl spiral coil single channel microchip was fabricated and alginate GDL mixture containing β-glucosidase was injected to the microchannel prior to gelation. Enzymatic conversion was performed by pumping substrate (pNPG) through the microchannel. The results indicated that the entire substrate was converted continuously during 24h without any leakage or deactivation of ...
Black carrots contain anthocyanins possessing enhanced physiological activities. Explants of youn... more Black carrots contain anthocyanins possessing enhanced physiological activities. Explants of young black carrot shoots were cultured in Murashige and Skoog (MS) medium for callus initiation and were transferred to new MS medium supplemented with four different combinations of 2,4-dichlorophenoxyacetic acid and kinetin. Subsequently, the lyophilized calli and black carrot harvested from fields were subjected to ultrasound extraction with ethanol at a ratio of 1:15 (w:v). Obtained extracts were applied to various human cancer cell lines including MCF-7 SK-BR-3 and MDA-MB-231 (human breast adenocarcinomas), HT-29 (human colon adenocarcinoma), PC-3 (human prostate adenocarcinoma), Neuro 2A (Musmusculus neuroblastoma) cancer cell lines and VERO (African green monkey kidney) normal cell line by MTT assay. The highest cytotoxic activity was achieved against Neuro-2A cell lines exhibiting viability of 38-46% at 6.25 μg/ml concentration for all calli and natural extracts. However, a significantly high IC50 value of 170.13 μg/ml was attained in normal cell line VERO indicating that its natural counterpart is an ideal candidate for treatment of brain cancer without causing negative effects to normal healthy cells.
The aim of this work was to optimize total phenolic yield of Arbutus unedo fruits using supercrit... more The aim of this work was to optimize total phenolic yield of Arbutus unedo fruits using supercritical fluid extraction. A Box-Behnken statistical design was used to evaluate the effect of various values of pressure (50-300 bar), temperature (30-801C) and concentration of ethanol as co-solvent (0-20%) by CO 2 flow rate of 15 g/min for 60 min. The most effective variable was co-solvent ratio (po0.005). Evaluative criteria for both dependent variables (total phenols and radical scavenging activity) in the model were assigned maximum. Optimum extraction conditions were elicited as 60 bar, 481C and 19.7% yielding 25.72 mg gallic acid equivalent (GAE) total phenols/g extract and 99.9% radical scavenging capacity, which were higher than the values obtained by conventional water (24.89 mg/g; 83.8%) and ethanol (15.12 mg/g; 95.8%) extractions demonstrating challenges as a green separation process with improved product properties for industrial applications.
Journal of Pharmaceutical and Biomedical Analysis, 2013
Astragalus species are widely used as health foods and dietary supplements, as well as drugs in t... more Astragalus species are widely used as health foods and dietary supplements, as well as drugs in traditional medicine. To rapidly evaluate metabolite similarities and differences among the EtOH extracts of the roots of eight commercial Astragalus spp., an approach based on direct analyses by ESI-MS followed by PCA of ESI-MS data, was carried out. Successively, quali-quantitative analyses of cycloartane derivatives in the eight Astragalus spp. by LC-ESI-MS(n) and PCA of LC-ESI-MS data were performed. This approach allowed to promptly highlighting metabolite similarities and differences among the various Astragalus spp. PCA results from LC-ESI-MS data of Astragalus samples were in reasonable agreement with both PCA results of ESI-MS data and quantitative results. This study affords an analytical method for the quali-quantitative determination of cycloartane derivatives in herbal preparations used as health and food supplements.
Plant Cell, Tissue and Organ Culture (PCTOC), 2013
The present study is investigating the immobilization of Rubia tinctorum L. suspension cultures. ... more The present study is investigating the immobilization of Rubia tinctorum L. suspension cultures. The effects of three inoculation volumes and three immobilization materials (loofa, sisal and jute) on fresh and dry weights of biomass as well as on alizarin and purpurin production were determined in this study. Two grams of four-week old callus tissue were transferred to liquid medium to establish suspension cultures. After four weeks, suspension cultures of R. tinctorum at concentration of 8 9 10 5 living cells/ml were immobilized with lignocellulosic materials and the cells were attached to all immobilization materials at the end of the first week and started to form aggregates on them. At the fourth week of these batch systems, biomass was measured approximately three times higher than the starting suspension cultures. The highest fresh weight was obtained (339.40 g/l) from sisal with inoculation ratio. Immobilization materials and inoculation volumes had an effect on dry weights, and accordingly, the most effective combinations were jute with (J3) and (J1) inoculation volumes with 7.86 and 7.82 g/l dry weights, respectively. Alizarin and purpurin contents of immobilized cells, analyzed with U-HPLC method, were 6.05 and 22.91 times higher than inoculated cells. All immobilization materials used in this study had no negative effect on to cells and biomass accumulation was enhanced. Concomitantly with rapid biomass increase, alizarin and purpurin production was ascended.
The aim of this work was to optimize the extraction parameters of tannins from the acorns and the... more The aim of this work was to optimize the extraction parameters of tannins from the acorns and the tanning properties. Experiments were planned to evaluate the effect of solvent/feed ratio (20–100ml/g), time (2–10h) and solvent mixture ratio (methanol–water) (0–100%) on extraction yields, tannin contents and total tannin amounts. Valonea tannin obtained under optimum conditions was applied to leather tanning process where filling coefficient (%) and shrinkage temperature (Ts) of the leathers were examined. Optimum extraction parameters were elicited as 100ml/g for solvent/feed ratio, 6h of process duration and solvent mixture ratio of 62% methanol–38% water. The filling coefficient of the leathers tanned with extracted valonea (57.81%) and the shrinkage temperature (75.5°C) was superior to the commercial valonea (52.83%, 73°C) implying the significant impact of process optimization. The tanning properties of the extracted valonea were satisfactory for the vegetable tanning in leather industry.
Gümüşhane üniversitesi fen bilimleri enstitüsü dergisi, Apr 15, 2021
Nanoparticles (NP), which can be produced for many different fields and purposes; are at size var... more Nanoparticles (NP), which can be produced for many different fields and purposes; are at size vary from nanometer to a micrometer. These particles can be prepared by different approaches such as chemical, physical and biological methods. However, the biological approach is the most promising approach among other methods due to its simplicity and environmentally friendly conditions. The production of the nanoparticle by means of a biological approach does not require any high temperature, acidic/basic conditions and hazardous chemicals. Therefore, this method is named "green synthesis". Development in microtechnology has had profound effects in many areas such as drug discovery, biology, diagnosis, and tissue engineering. Microfluidics which focuses on the processing of liquids in microscale systems has attracted wide attention in the production process of nanoparticles due to precise control and fast mixing. The main purpose of this study is to produce and characterize metal nanoparticles by combining microsystems and green synthesis approaches. For this purpose, in the first step, the design of microsystems that suitable for the flow of different phases was performed. In the second step, ZnO nanoparticle synthesis was carried out using the red cabbage (Brassica oleracea var.capitata f. Rubra) extracts. The synthesis of nanoparticles achieved by optimizing different parameters such as; extract: zinc ratio, zinc solution concentration, flow rates, and flow rates ratio in the microsystem and temperature. The results showed that the herbal red cabbage components can be used for the green synthesis of ZnO nanoparticles.
Bu calismada, Rubia tinctorum L. callus ve hucre suspansiyon kulturlerine 100 mM ve 200 mM konsan... more Bu calismada, Rubia tinctorum L. callus ve hucre suspansiyon kulturlerine 100 mM ve 200 mM konsantrasyonlarda tuz stresi uygulanarak elde edilen biyokutlelerdeki yas ve kuru agirliklar (g), bagil kuru agirlik oranlari (mg/g kuru agirlik) ve alizarin ve purpurin icerikleri uzerine etkileri belirlenmistir. Tuz consantrasyonundaki artisa bagli olarak, callus ve hucre suspansiyon kulturlerinden elde edilen biyokutle azalmistir. Kallus kulturlerindeki hucrelerde dusuk canlilik ve cogalma oranina ragmen, biyokutle belirgin bir dusus gostermemistir. Kallus kulturlerinde tuz konsantrasyonu arttikca alizarin ve purpurin icerigi azalmistir, ancak bu bilesiklerin miktari hucre suspansiyon kulturlerinde artmistir. Yapilan denemelerde inokulasyon oranlarinin yas ve kuru agirlik miktari ve alizarin ve purpurin icerigi uzerine etkili oldugu tespit edilmistir. Hucre suspansiyon kulturlerinde 1:2 inokulasyon orani daha yuksek alizarin ve purpurin icerigi saglarken, 1:4 inokusyon oraninda biyokutle miktari daha fazladir. En yuksek alizarin ( 3.183 mg/g) ve purpurin ( 1.153 mg/g) icerikleri 1:2 inokulasyon oraninda ve 200 mM NaCl iceren besin ortamindan tespit edilmistir.
ABSTRACT Aims of this study were to isolate endophytes from different parts of hazelnut – Corylus... more ABSTRACT Aims of this study were to isolate endophytes from different parts of hazelnut – Corylus avellana L. to obtain bioactive secondary metabolites and search for the presence of gene region of taxadiene synthase (Ts), a key enzyme in taxol biosynthesis, on selected fungi. Fourteen fungal species were isolated and cultured for the screening studies. The cell-free fermentation broths were extracted with chloroform. The chloroform extracts were tested for cytotoxic activity by MTT method. Based on the activity results and chemical profiles, the isolate identified as Phomopsis amygdali by internal transcribed spaces (ITS) sequence analysis using ITS1 primer was selected for further studies. After large-scale fermentation and purification studies, two major compounds, one of which turned out to be a new secondary metabolite, were isolated and characterized. Structure of the new metabolite was elucidated as (S)-4-butoxy-6-((S)-1-hydroxypentyl)-5,6-dihydro-2H-pyran-2-one by the extensive use of 1D and 2D NMR, and HR-MS, whereas the known compound was identified as (−)pestalotin. Additionally, to evaluate taxol-producing potential of the selected isolate, a PCR amplification study followed by gel electrophoresis analysis was carried out revealing no Ts gene region.
Plant Cell, Tissue and Organ Culture (PCTOC), 2012
There was a typing error in the second author's first name in the original publication. The name ... more There was a typing error in the second author's first name in the original publication. The name shown in this erratum is correct.
2018 IEEE Micro Electro Mechanical Systems (MEMS), 2018
In this paper, we demonstrate the dipstick-based digitisation and detection of bacterial sample o... more In this paper, we demonstrate the dipstick-based digitisation and detection of bacterial sample of concentration down to 103 CFU/ml. The significance of this work is that we are able to detect concentrations of bacteria relevant for urinary tract infection (UTI) with minimal handling time and without the need for complicated external equipment.
The aim of this study was to formulate silica and alginate hydrogels for immobilization of β-gluc... more The aim of this study was to formulate silica and alginate hydrogels for immobilization of β-glucosidase. For this purpose, enzyme kinetics in hydrogels were determined, activity of immobilized enzymes was compared with that of free enzyme, and structures of silica and alginate hydrogels were characterized in terms of surface area and pore size. The addition of polyethylene oxide improved the mechanical strength of the silica gels and 68% of the initial activity of the enzyme was preserved after immobilizing into tetraethyl orthosilicate-polyethylene oxide matrix where the relative activity in alginate beads was 87%. The immobilized β-glucosidase was loaded into glass-silicon-glass microreactors and catalysis of 4-nitrophenyl β-d-glucopyranoside was carried out at various retention times (5, 10, and 15 min) to compare the performance of silica and alginate hydrogels as immobilization matrices. The results indicated that alginate hydrogels exhibited slightly better properties than silica, which can be utilized for biocatalysis in microfluidic platforms.
The objective of this study was to develop an injectable alginate based formulation for immobiliz... more The objective of this study was to develop an injectable alginate based formulation for immobilizing enzymes into microfluidic systems. The gelation was induced upon lowering the pH by addition of d-glucono-δ-lactone (GDL) and release of Ca(+) ions from solid CaCO3. The effects of GDL concentration on enzymatic activity and gelation time were investigated. The results indicated that increasing the GDL concentration increased both surface area and enzymatic activity. Also, chitosan was added to the formulation at different ratios to enhance the stability of enzyme during immobilization. For microfluidic application, 100μl spiral coil single channel microchip was fabricated and alginate GDL mixture containing β-glucosidase was injected to the microchannel prior to gelation. Enzymatic conversion was performed by pumping substrate (pNPG) through the microchannel. The results indicated that the entire substrate was converted continuously during 24h without any leakage or deactivation of ...
Black carrots contain anthocyanins possessing enhanced physiological activities. Explants of youn... more Black carrots contain anthocyanins possessing enhanced physiological activities. Explants of young black carrot shoots were cultured in Murashige and Skoog (MS) medium for callus initiation and were transferred to new MS medium supplemented with four different combinations of 2,4-dichlorophenoxyacetic acid and kinetin. Subsequently, the lyophilized calli and black carrot harvested from fields were subjected to ultrasound extraction with ethanol at a ratio of 1:15 (w:v). Obtained extracts were applied to various human cancer cell lines including MCF-7 SK-BR-3 and MDA-MB-231 (human breast adenocarcinomas), HT-29 (human colon adenocarcinoma), PC-3 (human prostate adenocarcinoma), Neuro 2A (Musmusculus neuroblastoma) cancer cell lines and VERO (African green monkey kidney) normal cell line by MTT assay. The highest cytotoxic activity was achieved against Neuro-2A cell lines exhibiting viability of 38-46% at 6.25 μg/ml concentration for all calli and natural extracts. However, a significantly high IC50 value of 170.13 μg/ml was attained in normal cell line VERO indicating that its natural counterpart is an ideal candidate for treatment of brain cancer without causing negative effects to normal healthy cells.
The aim of this work was to optimize total phenolic yield of Arbutus unedo fruits using supercrit... more The aim of this work was to optimize total phenolic yield of Arbutus unedo fruits using supercritical fluid extraction. A Box-Behnken statistical design was used to evaluate the effect of various values of pressure (50-300 bar), temperature (30-801C) and concentration of ethanol as co-solvent (0-20%) by CO 2 flow rate of 15 g/min for 60 min. The most effective variable was co-solvent ratio (po0.005). Evaluative criteria for both dependent variables (total phenols and radical scavenging activity) in the model were assigned maximum. Optimum extraction conditions were elicited as 60 bar, 481C and 19.7% yielding 25.72 mg gallic acid equivalent (GAE) total phenols/g extract and 99.9% radical scavenging capacity, which were higher than the values obtained by conventional water (24.89 mg/g; 83.8%) and ethanol (15.12 mg/g; 95.8%) extractions demonstrating challenges as a green separation process with improved product properties for industrial applications.
Journal of Pharmaceutical and Biomedical Analysis, 2013
Astragalus species are widely used as health foods and dietary supplements, as well as drugs in t... more Astragalus species are widely used as health foods and dietary supplements, as well as drugs in traditional medicine. To rapidly evaluate metabolite similarities and differences among the EtOH extracts of the roots of eight commercial Astragalus spp., an approach based on direct analyses by ESI-MS followed by PCA of ESI-MS data, was carried out. Successively, quali-quantitative analyses of cycloartane derivatives in the eight Astragalus spp. by LC-ESI-MS(n) and PCA of LC-ESI-MS data were performed. This approach allowed to promptly highlighting metabolite similarities and differences among the various Astragalus spp. PCA results from LC-ESI-MS data of Astragalus samples were in reasonable agreement with both PCA results of ESI-MS data and quantitative results. This study affords an analytical method for the quali-quantitative determination of cycloartane derivatives in herbal preparations used as health and food supplements.
Plant Cell, Tissue and Organ Culture (PCTOC), 2013
The present study is investigating the immobilization of Rubia tinctorum L. suspension cultures. ... more The present study is investigating the immobilization of Rubia tinctorum L. suspension cultures. The effects of three inoculation volumes and three immobilization materials (loofa, sisal and jute) on fresh and dry weights of biomass as well as on alizarin and purpurin production were determined in this study. Two grams of four-week old callus tissue were transferred to liquid medium to establish suspension cultures. After four weeks, suspension cultures of R. tinctorum at concentration of 8 9 10 5 living cells/ml were immobilized with lignocellulosic materials and the cells were attached to all immobilization materials at the end of the first week and started to form aggregates on them. At the fourth week of these batch systems, biomass was measured approximately three times higher than the starting suspension cultures. The highest fresh weight was obtained (339.40 g/l) from sisal with inoculation ratio. Immobilization materials and inoculation volumes had an effect on dry weights, and accordingly, the most effective combinations were jute with (J3) and (J1) inoculation volumes with 7.86 and 7.82 g/l dry weights, respectively. Alizarin and purpurin contents of immobilized cells, analyzed with U-HPLC method, were 6.05 and 22.91 times higher than inoculated cells. All immobilization materials used in this study had no negative effect on to cells and biomass accumulation was enhanced. Concomitantly with rapid biomass increase, alizarin and purpurin production was ascended.
The aim of this work was to optimize the extraction parameters of tannins from the acorns and the... more The aim of this work was to optimize the extraction parameters of tannins from the acorns and the tanning properties. Experiments were planned to evaluate the effect of solvent/feed ratio (20–100ml/g), time (2–10h) and solvent mixture ratio (methanol–water) (0–100%) on extraction yields, tannin contents and total tannin amounts. Valonea tannin obtained under optimum conditions was applied to leather tanning process where filling coefficient (%) and shrinkage temperature (Ts) of the leathers were examined. Optimum extraction parameters were elicited as 100ml/g for solvent/feed ratio, 6h of process duration and solvent mixture ratio of 62% methanol–38% water. The filling coefficient of the leathers tanned with extracted valonea (57.81%) and the shrinkage temperature (75.5°C) was superior to the commercial valonea (52.83%, 73°C) implying the significant impact of process optimization. The tanning properties of the extracted valonea were satisfactory for the vegetable tanning in leather industry.
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