- Email: [email protected]
Isolation and identification of Salmonella enteritidis from eggs sold in Bucharest markets
Abstracts / Current Opinion in Biotechnology 22S (2011) S15–S152
Acknowledgement: This work was financed by the Ministry of Sciences and Higher Education of Poland and European Union under Project No. POIG 01.01.02-00-074/09. doi:10.1016/j.copbio.2011.05.294
S95
and 26.37 g NaCl/L. In next step the optimized medium was used for erythritol biosynthesis in bioreactor. Acknowledgements: This work was financed by the Ministry of Sciences and Higher Education of Poland and European Union Structural Founds, Project No. POIG 01.01.02-00-074/09. doi:10.1016/j.copbio.2011.05.296
I19 Erythritol production by Yarrowia lipolytica DN I W 2a and its UV mutants on media containing glycerol Izabela Musial, Maria Wojtatowicz, Piotr Juszczyk, Anita Rywinska Department of Biotechnology and Food Microbiology, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
I21 Single and mixed yeast adjunct cultures for cheese production Grzegorz Szczepaniak 1 , Marek Szoltysik 2 , Xymena Polomska 1 , Jozefa Chrzanowska 2 , Maria Wojtatowicz 1 1
E-mail address: [email protected] (I. Musial) Erythritol biosynthesis in synthetic media containing glucose or fructose in various aspects has been focused extensively. Only a few reports showed the production of this polyol with glycerol by Y. lipolytica yeasts. The aim of the studies was to evaluate dynamic and yield of erythritol production from by-products of biodiesel production such as pure glycerol and glycerin waste by wild strain Y. lipolytica DN I W 2a and its UV mutants in submerged cultivations. The processes were compared for their product yields, volumetric productivity and concentration of unwanted by-products for three deferent mediums. The maximum concentration of erythritol (69.7 g dm−3 ) was achieved in the culture of UV mutant in medium with 150 g dm−3 of pure glycerol and 10 g dm−3 of YE and 50 g dm−3 of NaCl. The highest erythritol yield and volumetric productivity obtained were 0.45 g g−1 and 0.72 g dm−3 h−1 , respectively. Acknowledgements: This work was financed by the Ministry of Sciences and Higher Education of Poland and European Union Structural Founds, Project No. POIG 01.01.02-00-074/09. doi:10.1016/j.copbio.2011.05.295
I20 Optimization of erythritol production from glycerol by Yarrowia lipolytica Wratislavia K1
Department of Biotechnology and Food Microbiology, Wroclaw University, Wroclaw, Poland 2 Department of Animal Products Technology and Quality Management, Wroclaw University, Wroclaw, Poland E-mail address: [email protected] (M. Wojtatowicz)
There are strains among yeasts naturally occurring in many cheese varieties that reveal attractive technological properties. Therefore, they can be used as adjunct cultures for acceleration of cheese ripening. The aim of the study was to examine the effect of single and mixed cultures of Yarrowia lipolytica and Debaryomyces hansenii yeasts on cheese maturation. Two strains of Y. lipolytica (PII6c, JII1c) and two strains of D. hansenii (KI2a, BI6a) originating from blue-veined cheese were used individually and in combinations: PII6c with BI6a, JII1c with KI2a. Model cheeses were produced from milk inoculated with yeasts (6 log cfu/mL) and with primary lactic acid starter. The growth of starter microflora as well as proteolytic and lipolytic changes was monitored during cheese ripening. It was shown that lactic acid bacteria grew very well in cheeses with yeasts addition reaching the level of 9 log cfu/g. Yeast microflora were less numerous and not exceeded 7 log cfu/g. In cheeses obtained with mixed yeast cultures population of Y. lipolytica predominated over D. hansenii. In all cheeses inoculated with yeasts much deeper protein and fat degradation took place than in control cheese. The most advanced degradation changes were observed in cheeses with double strain adjuncts.
Izabela Musial 1 , Marta Marcinkiewicz 1 , Edmund Cibis 2 , Anita Rywinska 1 , Piotr Juszczyk 1 , Waldemar Rymowicz 1
doi:10.1016/j.copbio.2011.05.297
1
Department of Biotechnology and Food Microbiology, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland 2 Department of Bioprocess Engineering, Wroclaw University of Economics, Wroclaw, Poland
I22
E-mail address: Rymowicz)
Anca Maria Galis 1 , Ilie Van 1 , Lucian Ionel Ilie 2 , Laurentiu Tudor 2
[email protected]
(W.
The aim of this study was to examine the effect of culture medium constitutes on erythritol production by Y. lipolytica Wratislavia K1. Central composite rotatable experimental design was employed to optimize the medium components for maximum production of erythritol. Nutritional parameters such as concentration of (NH4 )2 SO4 , KH2 PO4 and NaCl were focused in this study to enhance the erythritol production. The design contains a total of 20 experimental trials in which the first 14 organized in a factorial design and from 15 to 20 involving the replications of the central points. Cultures for erythritol production were conducted on a shaker at 160 rpm in 300 ml flasks with 25 ml medium at 30◦ C for 7 days. The optimal conditions for maximizing erythritol production (30.0 g/L) were at 2.245 g (NH4 )2 SO4 /L, 0.221 g KH2 PO4 /L
Isolation and identification of Salmonella enteritidis from eggs sold in Bucharest markets
1
Animal Science Department, University of Agricultural Science and Veterinary Medicine, Romania 2 Veterinary Medicine Department, University of Agricultural Science and Veterinary Medicine, Romania E-mail address: anca [email protected] (A.M. Galis) Salmonellae have long been associated with eggs, being the most important human pathogen carried by this food product. The changes in the albumen and vitelline membrane during storage slowly alter conditions so that they are increasingly favorable for S. enteritidis growth. This study was performed in order to establish Salmonella contamination in various types of table eggs sold in Bucharest markets, as well as to identify Salmonella enteritidis in these types of food products. For this, 100 table eggs were collected randomly from 10 retail stores in Bucharest over a period
S96
Abstracts / Current Opinion in Biotechnology 22S (2011) S15–S152
of 2 months, in 2011. Ten samples from each store were collected and transferred to the laboratory. For Salmonella isolation, conventional culture methods were performed. For confirmation and S. enteritidis serovar determination, a PCR reaction assay was used, with Prot6E gene primers (Prot6e-5 and Prot6e-6), specific for S. enteritidis serovar. 37 samples out of 100 showed positive results for Salmonella spp. presence, while 24 out of them were contaminated with Salmonella enteritidis. The main conclusion was that table eggs represent a potential risk considering salmonellosis, especially due to the existence of S. enteritidis serovar. doi:10.1016/j.copbio.2011.05.298
threshold level. However, the current situation about the foods we consume is pretty uncertain. In this present study detection of GM maize and soya in food products obtained from local retail shops was performed. The samples included, maize flour, soya flour, canned maize, bread, cake, meat products and similar soya and maize containing foods. The samples were analyzed for CaMV 35S promoter and nos terminator sequences which are the most common sequences inserted in GM crops. The samples positive for both or either sequences were evaluated as GM positive. The negative maize and soya samples were detected for zein and lectin respectively for the determination of detectible DNA in the sample. The results indicated that 10 of 30 samples detected, were positive for either or both of the novel sequences.
I23
doi:10.1016/j.copbio.2011.05.300
Relationship of somatic cell count with milk yield and composition in Holstein and Romanian Spotted cow crossbreed population
I25
Lucian Ionel Ilie 1 , Anca Maria Galis 2 , Laurentiu Tudor 1 1
Veterinary Medicine Department, University of Agricultural Sciences and Veterinary Medicine of Bucharest, Romania 2 Animal Science Department, University of Agricultural Sciences and Veterinary Medicine of Bucharest, Romania E-mail address: [email protected] (L.I. Ilie)
The objective of this study was to analyze the relationship between somatic cell count (SCC), milk yield (MY), fat and protein percentage (FP/PP), fat and protein yield (FY/PY), using analysis of variance and correlation analysis in Romanian crossbreed cows. The records were obtained from ten commercial herds, located in different counties near Bucharest, during September 2010 and January 2011. The cows presented different ages, being at first, second, third, fourth or later parity, this specific fact being used as a variation factor considering the studied parameters. MY, FP, PP, FY and PY showed variations, with the highest values for cows at first and second parity, while the lowest values were associated with cows at fourth and later parity, the situation for SCC being totally opposite. Analysis of variance showed highly significant effect of SCC values on MY and composition. The correlations were highly negative between SCC, MY and PY, and highly positive for SCC, FY, FP and PP. There was no significant relationship between FP and PY (P > 0.05). The results of the present study provide relevant data for assessing milk production in an area considered important for milk supply in Bucharest. doi:10.1016/j.copbio.2011.05.299
I24
Encapsulation of food flavors via coacervation method Perihan Merve Buldur, Fatma Nese Kok Molecular Biology and Genetics Department, Istanbul Technical University, Istanbul, Turkey E-mail address: [email protected] (P.M. Buldur) Flavors are used in many areas, such as food, cosmetic, pharmaceutical and detergent industries to increase taste and/or odor. These highly valuable compounds lose their effect beginning from the production step due to their volatile and oxidation labile nature. The decreases in properties continue during the transfer and storage of the product. Encapsulation of flavors into different materials (e.g. gelatin, gum arabic, whey proteins, and pectin) is a well known method to solve this problem. In this study, the potential of coacervation method in the efficient encapsulation of food flavors were studied. The model flavors, d-limonene and 2-phenylethanol, were encapsulated into different ratio of gum arabic/gelatin mixtures. Prepared microcapsules were crosslinked by a natural, non-toxic agent, namely genipin. The microbeads were then collected and dried by lyophilization. Preparation conditions and different crosslinking agent concentrations were studied for their effect on coacervation properties and flavor retention during drying and storage. Microbeads were visualized in fluorescence microscopy using nile red as lipid staining dye. It was seen that increasing the gelatin and gum arabic concentration in the medium to more than 40% and 50%, respectively, caused aggregation of the newly formed microbeads. Optimum ratio was found to be 2:3 for gum arabic/gelatin. doi:10.1016/j.copbio.2011.05.301
PCR detection of genetically modified maize and soya in mildly and highly processed foods
I26
Ozge Ozgen Arun, Funda Yilmaz
Selection of lactic acid bacteria strains producing exopolysaccharides
Besin Hijyeni ve Teknolojisi Anabilim Dali, Veteriner Fakultesi, Istanbul, Turkey
Ionela Sarbu 1 , Tatiana Vassu 1 , Ileana Stoica 1 , Emanuel Vamanu 2 , Diana Roxana Pelinescu 1
E-mail address: [email protected] (O.O. Arun) Despite the announced advances, genetically modified organisms (GMO) have received a very strong consumer reaction since they were first commercialized. For this purpose numerous countries set up their official regulations on labeling of GMOs and GMO derivate foods. Finally regulation on traceability and labeling of GM foods, have come into force in our country. The Regulation stipulates the labeling of foods that contain GM material above the
1
Genetics department, Faculty of Biology, Bucharest, Romania Biotechnology Department, Faculty of Biotechnology, University of Agronomical Science and Veterinary Medicine, Bucharest, Romania 2
E-mail address: [email protected] (D.R. Pelinescu) Production of exopolysaccharides (EPS) generated a high interest due to their important industrial application and beneficial effects on human health. Main goal of our study was selection of
Acknowledgement: This work was financed by the Ministry of Sciences and Higher Education of Poland and European Union under Project No. POIG 01.01.02-00-074/09. doi:10.1016/j.copbio.2011.05.294
S95
and 26.37 g NaCl/L. In next step the optimized medium was used for erythritol biosynthesis in bioreactor. Acknowledgements: This work was financed by the Ministry of Sciences and Higher Education of Poland and European Union Structural Founds, Project No. POIG 01.01.02-00-074/09. doi:10.1016/j.copbio.2011.05.296
I19 Erythritol production by Yarrowia lipolytica DN I W 2a and its UV mutants on media containing glycerol Izabela Musial, Maria Wojtatowicz, Piotr Juszczyk, Anita Rywinska Department of Biotechnology and Food Microbiology, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
I21 Single and mixed yeast adjunct cultures for cheese production Grzegorz Szczepaniak 1 , Marek Szoltysik 2 , Xymena Polomska 1 , Jozefa Chrzanowska 2 , Maria Wojtatowicz 1 1
E-mail address: [email protected] (I. Musial) Erythritol biosynthesis in synthetic media containing glucose or fructose in various aspects has been focused extensively. Only a few reports showed the production of this polyol with glycerol by Y. lipolytica yeasts. The aim of the studies was to evaluate dynamic and yield of erythritol production from by-products of biodiesel production such as pure glycerol and glycerin waste by wild strain Y. lipolytica DN I W 2a and its UV mutants in submerged cultivations. The processes were compared for their product yields, volumetric productivity and concentration of unwanted by-products for three deferent mediums. The maximum concentration of erythritol (69.7 g dm−3 ) was achieved in the culture of UV mutant in medium with 150 g dm−3 of pure glycerol and 10 g dm−3 of YE and 50 g dm−3 of NaCl. The highest erythritol yield and volumetric productivity obtained were 0.45 g g−1 and 0.72 g dm−3 h−1 , respectively. Acknowledgements: This work was financed by the Ministry of Sciences and Higher Education of Poland and European Union Structural Founds, Project No. POIG 01.01.02-00-074/09. doi:10.1016/j.copbio.2011.05.295
I20 Optimization of erythritol production from glycerol by Yarrowia lipolytica Wratislavia K1
Department of Biotechnology and Food Microbiology, Wroclaw University, Wroclaw, Poland 2 Department of Animal Products Technology and Quality Management, Wroclaw University, Wroclaw, Poland E-mail address: [email protected] (M. Wojtatowicz)
There are strains among yeasts naturally occurring in many cheese varieties that reveal attractive technological properties. Therefore, they can be used as adjunct cultures for acceleration of cheese ripening. The aim of the study was to examine the effect of single and mixed cultures of Yarrowia lipolytica and Debaryomyces hansenii yeasts on cheese maturation. Two strains of Y. lipolytica (PII6c, JII1c) and two strains of D. hansenii (KI2a, BI6a) originating from blue-veined cheese were used individually and in combinations: PII6c with BI6a, JII1c with KI2a. Model cheeses were produced from milk inoculated with yeasts (6 log cfu/mL) and with primary lactic acid starter. The growth of starter microflora as well as proteolytic and lipolytic changes was monitored during cheese ripening. It was shown that lactic acid bacteria grew very well in cheeses with yeasts addition reaching the level of 9 log cfu/g. Yeast microflora were less numerous and not exceeded 7 log cfu/g. In cheeses obtained with mixed yeast cultures population of Y. lipolytica predominated over D. hansenii. In all cheeses inoculated with yeasts much deeper protein and fat degradation took place than in control cheese. The most advanced degradation changes were observed in cheeses with double strain adjuncts.
Izabela Musial 1 , Marta Marcinkiewicz 1 , Edmund Cibis 2 , Anita Rywinska 1 , Piotr Juszczyk 1 , Waldemar Rymowicz 1
doi:10.1016/j.copbio.2011.05.297
1
Department of Biotechnology and Food Microbiology, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland 2 Department of Bioprocess Engineering, Wroclaw University of Economics, Wroclaw, Poland
I22
E-mail address: Rymowicz)
Anca Maria Galis 1 , Ilie Van 1 , Lucian Ionel Ilie 2 , Laurentiu Tudor 2
[email protected]
(W.
The aim of this study was to examine the effect of culture medium constitutes on erythritol production by Y. lipolytica Wratislavia K1. Central composite rotatable experimental design was employed to optimize the medium components for maximum production of erythritol. Nutritional parameters such as concentration of (NH4 )2 SO4 , KH2 PO4 and NaCl were focused in this study to enhance the erythritol production. The design contains a total of 20 experimental trials in which the first 14 organized in a factorial design and from 15 to 20 involving the replications of the central points. Cultures for erythritol production were conducted on a shaker at 160 rpm in 300 ml flasks with 25 ml medium at 30◦ C for 7 days. The optimal conditions for maximizing erythritol production (30.0 g/L) were at 2.245 g (NH4 )2 SO4 /L, 0.221 g KH2 PO4 /L
Isolation and identification of Salmonella enteritidis from eggs sold in Bucharest markets
1
Animal Science Department, University of Agricultural Science and Veterinary Medicine, Romania 2 Veterinary Medicine Department, University of Agricultural Science and Veterinary Medicine, Romania E-mail address: anca [email protected] (A.M. Galis) Salmonellae have long been associated with eggs, being the most important human pathogen carried by this food product. The changes in the albumen and vitelline membrane during storage slowly alter conditions so that they are increasingly favorable for S. enteritidis growth. This study was performed in order to establish Salmonella contamination in various types of table eggs sold in Bucharest markets, as well as to identify Salmonella enteritidis in these types of food products. For this, 100 table eggs were collected randomly from 10 retail stores in Bucharest over a period
S96
Abstracts / Current Opinion in Biotechnology 22S (2011) S15–S152
of 2 months, in 2011. Ten samples from each store were collected and transferred to the laboratory. For Salmonella isolation, conventional culture methods were performed. For confirmation and S. enteritidis serovar determination, a PCR reaction assay was used, with Prot6E gene primers (Prot6e-5 and Prot6e-6), specific for S. enteritidis serovar. 37 samples out of 100 showed positive results for Salmonella spp. presence, while 24 out of them were contaminated with Salmonella enteritidis. The main conclusion was that table eggs represent a potential risk considering salmonellosis, especially due to the existence of S. enteritidis serovar. doi:10.1016/j.copbio.2011.05.298
threshold level. However, the current situation about the foods we consume is pretty uncertain. In this present study detection of GM maize and soya in food products obtained from local retail shops was performed. The samples included, maize flour, soya flour, canned maize, bread, cake, meat products and similar soya and maize containing foods. The samples were analyzed for CaMV 35S promoter and nos terminator sequences which are the most common sequences inserted in GM crops. The samples positive for both or either sequences were evaluated as GM positive. The negative maize and soya samples were detected for zein and lectin respectively for the determination of detectible DNA in the sample. The results indicated that 10 of 30 samples detected, were positive for either or both of the novel sequences.
I23
doi:10.1016/j.copbio.2011.05.300
Relationship of somatic cell count with milk yield and composition in Holstein and Romanian Spotted cow crossbreed population
I25
Lucian Ionel Ilie 1 , Anca Maria Galis 2 , Laurentiu Tudor 1 1
Veterinary Medicine Department, University of Agricultural Sciences and Veterinary Medicine of Bucharest, Romania 2 Animal Science Department, University of Agricultural Sciences and Veterinary Medicine of Bucharest, Romania E-mail address: [email protected] (L.I. Ilie)
The objective of this study was to analyze the relationship between somatic cell count (SCC), milk yield (MY), fat and protein percentage (FP/PP), fat and protein yield (FY/PY), using analysis of variance and correlation analysis in Romanian crossbreed cows. The records were obtained from ten commercial herds, located in different counties near Bucharest, during September 2010 and January 2011. The cows presented different ages, being at first, second, third, fourth or later parity, this specific fact being used as a variation factor considering the studied parameters. MY, FP, PP, FY and PY showed variations, with the highest values for cows at first and second parity, while the lowest values were associated with cows at fourth and later parity, the situation for SCC being totally opposite. Analysis of variance showed highly significant effect of SCC values on MY and composition. The correlations were highly negative between SCC, MY and PY, and highly positive for SCC, FY, FP and PP. There was no significant relationship between FP and PY (P > 0.05). The results of the present study provide relevant data for assessing milk production in an area considered important for milk supply in Bucharest. doi:10.1016/j.copbio.2011.05.299
I24
Encapsulation of food flavors via coacervation method Perihan Merve Buldur, Fatma Nese Kok Molecular Biology and Genetics Department, Istanbul Technical University, Istanbul, Turkey E-mail address: [email protected] (P.M. Buldur) Flavors are used in many areas, such as food, cosmetic, pharmaceutical and detergent industries to increase taste and/or odor. These highly valuable compounds lose their effect beginning from the production step due to their volatile and oxidation labile nature. The decreases in properties continue during the transfer and storage of the product. Encapsulation of flavors into different materials (e.g. gelatin, gum arabic, whey proteins, and pectin) is a well known method to solve this problem. In this study, the potential of coacervation method in the efficient encapsulation of food flavors were studied. The model flavors, d-limonene and 2-phenylethanol, were encapsulated into different ratio of gum arabic/gelatin mixtures. Prepared microcapsules were crosslinked by a natural, non-toxic agent, namely genipin. The microbeads were then collected and dried by lyophilization. Preparation conditions and different crosslinking agent concentrations were studied for their effect on coacervation properties and flavor retention during drying and storage. Microbeads were visualized in fluorescence microscopy using nile red as lipid staining dye. It was seen that increasing the gelatin and gum arabic concentration in the medium to more than 40% and 50%, respectively, caused aggregation of the newly formed microbeads. Optimum ratio was found to be 2:3 for gum arabic/gelatin. doi:10.1016/j.copbio.2011.05.301
PCR detection of genetically modified maize and soya in mildly and highly processed foods
I26
Ozge Ozgen Arun, Funda Yilmaz
Selection of lactic acid bacteria strains producing exopolysaccharides
Besin Hijyeni ve Teknolojisi Anabilim Dali, Veteriner Fakultesi, Istanbul, Turkey
Ionela Sarbu 1 , Tatiana Vassu 1 , Ileana Stoica 1 , Emanuel Vamanu 2 , Diana Roxana Pelinescu 1
E-mail address: [email protected] (O.O. Arun) Despite the announced advances, genetically modified organisms (GMO) have received a very strong consumer reaction since they were first commercialized. For this purpose numerous countries set up their official regulations on labeling of GMOs and GMO derivate foods. Finally regulation on traceability and labeling of GM foods, have come into force in our country. The Regulation stipulates the labeling of foods that contain GM material above the
1
Genetics department, Faculty of Biology, Bucharest, Romania Biotechnology Department, Faculty of Biotechnology, University of Agronomical Science and Veterinary Medicine, Bucharest, Romania 2
E-mail address: [email protected] (D.R. Pelinescu) Production of exopolysaccharides (EPS) generated a high interest due to their important industrial application and beneficial effects on human health. Main goal of our study was selection of