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Glenn R. Gibson - One of the best experts on this subject based on the ideXlab platform.
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a mixture of trans Galactooligosaccharides reduces markers of metabolic syndrome and modulates the fecal microbiota and immune function of overweight adults
Journal of Nutrition, 2013Co-Authors: Jelena Vulevic, George Tzortzis, Aleksandra Juric, Glenn R. GibsonAbstract:Metabolic syndrome is a set of disorders that increases the risk of developing cardiovascular disease. The gut microbiota is altered toward a less beneficial composition in overweight adults and this change can be accompanied by inflammation. Prebiotics such as Galactooligosaccharides can positively modify the gut microbiota and immune system; some may also reduce blood lipids. We assessed the effect of a galactooligosaccharide mixture [Bi 2 muno (B-GOS)] on markers of metabolic syndrome, gut microbiota, and immune function in 45 overweight adults with $3 risk factors associated with metabolic syndrome in a double-blind, randomized, placebo (maltodextrin)-controlled, crossover study (with a 4-wk wash-out period between interventions). Whole blood, saliva, feces, and anthropometric measurements were taken at the beginning, wk 6, and end of each 12-wk intervention period. Predominant groups of fecal bacteria were quantified and full blood count, markers of inflammation and lipidmetabolism, insulin, and glucose were measured. B-GOS increased the number of fecal bifidobacteria at the expense of less desirable groups of bacteria. Increases in fecal secretory IgA and decreases in fecal calprotectin, plasma C-reactive protein, insulin, total cholesterol (TC), TG, and the TC:HDL cholesterol ratio were also observed. Administration of B-GOS to overweight adults resulted in positive effects on the composition of the gut microbiota, the immune response, and insulin, TC, and TG concentrations. B-GOS may be a useful candidate for the enhancement of gastrointestinal health, immune function, and the reduction of metabolic syndrome risk factors in overweight adults. J. Nutr. doi: 10.3945/jn.112.166132.
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clinical trial the effects of a trans galactooligosaccharide prebiotic on faecal microbiota and symptoms in irritable bowel syndrome
Alimentary Pharmacology & Therapeutics, 2009Co-Authors: D B A Silk, George Tzortzis, Jelena Vulevic, A Davis, Glenn R. GibsonAbstract:Summary Background Gut microflora-mucosal interactions may be involved in the pathogenesis of irritable bowel syndrome (IBS). Aim To investigate the efficacy of a novel prebiotic trans-galactooligosaccharide in changing the colonic microflora and improve the symptoms in IBS sufferers. Methods In all, 44 patients with Rome II positive IBS completed a 12-week single centre parallel crossover controlled clinical trial. Patients were randomized to receive either 3.5 g/d prebiotic, 7 g/d prebiotic or 7 g/d placebo. IBS symptoms were monitored weekly and scored according to a 7-point Likert scale. Changes in faecal microflora, stool frequency and form (Bristol stool scale) subjective global assessment (SGA), anxiety and depression and QOL scores were also monitored. Results The prebiotic significantly enhanced faecal bifidobacteria (3.5 g/d P < 0.005; 7 g/d P < 0.001). Placebo was without effect on the clinical parameters monitored, while the prebiotic at 3.5 g/d significantly changed stool consistency (P < 0.05), improved flatulence (P < 0.05) bloating (P < 0.05), composite score of symptoms (P < 0.05) and SGA (P < 0.05). The prebiotic at 7 g/d significantly improved SGA (P < 0.05) and anxiety scores (P < 0.05). Conclusion The galactooligosaccharide acted as a prebiotic in specifically stimulating gut bifidobacteria in IBS patients and is effective in alleviating symptoms. These findings suggest that the prebiotic has potential as a therapeutic agent in IBS.
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Prebiotic evaluation of a novel galactooligosaccharide mixture produced by the enzymatic activity of Bifidobacterium bifidum NCIMB 41171, in healthy humans: a randomized, double-blind, crossover, placebo-controlled intervention study
The American journal of clinical nutrition, 2008Co-Authors: Flore Depeint, George Tzortzis, Jelena Vulevic, Kerry I'anson, Glenn R. GibsonAbstract:Background: Galactooligosaccharides are selectively fermented by the beneficial member of the colonic microflora contributing to the health of the host. Objective: We assessed the prebiotic potential of a novel galactooligosaccharide produced through the action of -galactosidases, originating from a probiotic Bifidobacterium bifidum strain, against a galactooligosaccharide produced through the action of an industrial -galactosidase and a placebo. Design: Fifty-nine healthy human volunteers participated in this study. Initially, the effect of the matrix on the prebiotic properties of a commercially available galactooligosaccharide (7 g/d) was assessed during 7-d treatment periods with a 7-d washout period in between. During the second phase, 30 volunteers were assigned to a sequence of treatments (7 d) differing in the amount of the novel galactooligosaccharide (0, 3.6, or 7 g/d). Stools were recovered before and after each intervention, and bacteria numbers were determined by fluorescent in situ hybridization. Results: Addition of the novel galactooligosaccharide mixture significantly increased the bifidobacterial population ratio compared with the placebo (P 0.05), whereas 7 g/d of the novel galactooligosaccharide significantly increased the bifidobacterial ratio compared with the commercial galactooligosaccharide (P 0.05). Moreover, a significant relation (P 0.001) between the bifidobacteria proportion and the novel galactooligosaccharide dose (0, 3.6, and 7 g/d) was observed. This relation was similar to the effect of the novel galactooligosaccharide on the prebiotic index of each dose. Conclusions: This study showed that galactooligosaccharide mixtures produced with different -galactosidases show different prebiotic properties and that, by using enzymes originating from bifidobacterial species, an increase in the bifidogenic properties of the prebiotic product is achievable. Am J Clin Nutr 2008;87: 785–91.
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Synthesis of prebiotic Galactooligosaccharides using whole cells of a novel strain, Bifidobacterium bifidum NCIMB 41171
Applied Microbiology and Biotechnology, 2005Co-Authors: George Tzortzis, Athanasios K. Goulas, Glenn R. GibsonAbstract:A novel strain of Bifidobacterium bifidum NCIMB 41171, isolated from a faecal sample from a healthy human volunteer and able to express β-galactosidase activity, was used in synthesis reactions for the production of galactooligosaccharide from lactose. The β-galactosidase activity of whole bifidobacterial cells showed an optimum activity at pH 6.8–7.0 and 40°C. The transgalactosylation activity of the B. bifidum cells from 50% (w/w) lactose resulted in a galactooligosaccharide mixture (20% w/w) comprising (w/w): 25% disaccharides, 35% trisaccharides, 25% tetrasaccharides and 15% pentasaccharides. Using different initial lactose concentrations, the conversion rate to Galactooligosaccharides was maximum (35%) when 55% (w/w) lactose was used. In fermentation experiments, B. bifidum showed an increased preference towards the produced galactooligosaccharide mixture, displaying higher growth rate and short-chain fatty acid production when compared with commercially available oligosaccharides.
George Tzortzis - One of the best experts on this subject based on the ideXlab platform.
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a mixture of trans Galactooligosaccharides reduces markers of metabolic syndrome and modulates the fecal microbiota and immune function of overweight adults
Journal of Nutrition, 2013Co-Authors: Jelena Vulevic, George Tzortzis, Aleksandra Juric, Glenn R. GibsonAbstract:Metabolic syndrome is a set of disorders that increases the risk of developing cardiovascular disease. The gut microbiota is altered toward a less beneficial composition in overweight adults and this change can be accompanied by inflammation. Prebiotics such as Galactooligosaccharides can positively modify the gut microbiota and immune system; some may also reduce blood lipids. We assessed the effect of a galactooligosaccharide mixture [Bi 2 muno (B-GOS)] on markers of metabolic syndrome, gut microbiota, and immune function in 45 overweight adults with $3 risk factors associated with metabolic syndrome in a double-blind, randomized, placebo (maltodextrin)-controlled, crossover study (with a 4-wk wash-out period between interventions). Whole blood, saliva, feces, and anthropometric measurements were taken at the beginning, wk 6, and end of each 12-wk intervention period. Predominant groups of fecal bacteria were quantified and full blood count, markers of inflammation and lipidmetabolism, insulin, and glucose were measured. B-GOS increased the number of fecal bifidobacteria at the expense of less desirable groups of bacteria. Increases in fecal secretory IgA and decreases in fecal calprotectin, plasma C-reactive protein, insulin, total cholesterol (TC), TG, and the TC:HDL cholesterol ratio were also observed. Administration of B-GOS to overweight adults resulted in positive effects on the composition of the gut microbiota, the immune response, and insulin, TC, and TG concentrations. B-GOS may be a useful candidate for the enhancement of gastrointestinal health, immune function, and the reduction of metabolic syndrome risk factors in overweight adults. J. Nutr. doi: 10.3945/jn.112.166132.
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a comprehensive investigation of the synthesis of prebiotic Galactooligosaccharides by whole cells of bifidobacterium bifidum ncimb 41171
Journal of Biotechnology, 2010Co-Authors: Ali Osman, George Tzortzis, Robert A Rastall, Dimitris CharalampopoulosAbstract:The synthesis of Galactooligosaccharides (GOS) by whole cells of Bifidobacterium bifidum NCIMB 41171 was investigated by developing a set of mathematical models. These were second order polynomial equations, which described responses related to the production of GOS constituents, the selectivity of lactose conversion into GOS, and the relative composition of the produced GOS mixture, as a function of the amount of biocatalyst, temperature, initial lactose concentration, and time. The synthesis reactions were followed for up to 36 h. Samples were withdrawn every 4 h, tested for β-galactosidase activity, and analysed for their carbohydrate content. GOS synthesis was well explained by the models, which were all significant (P<0.001). The GOS yield increased as temperature increased from 40°C to 60°C, as transgalactosylation became more pronounced compared to hydrolysis. The relative composition of GOS produced changed significantly with the initial lactose concentration (P<0.001); higher ratios of tri-, tetra-, and penta-Galactooligosaccharides to transgalactosylated disaccharides were obtained as lactose concentration increased. Time was a critical factor, as a balanced state between GOS synthesis and hydrolysis was roughly attained in most cases between 12 and 20 h, and was followed by more pronounced GOS hydrolysis than synthesis.
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clinical trial the effects of a trans galactooligosaccharide prebiotic on faecal microbiota and symptoms in irritable bowel syndrome
Alimentary Pharmacology & Therapeutics, 2009Co-Authors: D B A Silk, George Tzortzis, Jelena Vulevic, A Davis, Glenn R. GibsonAbstract:Summary Background Gut microflora-mucosal interactions may be involved in the pathogenesis of irritable bowel syndrome (IBS). Aim To investigate the efficacy of a novel prebiotic trans-galactooligosaccharide in changing the colonic microflora and improve the symptoms in IBS sufferers. Methods In all, 44 patients with Rome II positive IBS completed a 12-week single centre parallel crossover controlled clinical trial. Patients were randomized to receive either 3.5 g/d prebiotic, 7 g/d prebiotic or 7 g/d placebo. IBS symptoms were monitored weekly and scored according to a 7-point Likert scale. Changes in faecal microflora, stool frequency and form (Bristol stool scale) subjective global assessment (SGA), anxiety and depression and QOL scores were also monitored. Results The prebiotic significantly enhanced faecal bifidobacteria (3.5 g/d P < 0.005; 7 g/d P < 0.001). Placebo was without effect on the clinical parameters monitored, while the prebiotic at 3.5 g/d significantly changed stool consistency (P < 0.05), improved flatulence (P < 0.05) bloating (P < 0.05), composite score of symptoms (P < 0.05) and SGA (P < 0.05). The prebiotic at 7 g/d significantly improved SGA (P < 0.05) and anxiety scores (P < 0.05). Conclusion The galactooligosaccharide acted as a prebiotic in specifically stimulating gut bifidobacteria in IBS patients and is effective in alleviating symptoms. These findings suggest that the prebiotic has potential as a therapeutic agent in IBS.
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Prebiotic evaluation of a novel galactooligosaccharide mixture produced by the enzymatic activity of Bifidobacterium bifidum NCIMB 41171, in healthy humans: a randomized, double-blind, crossover, placebo-controlled intervention study
The American journal of clinical nutrition, 2008Co-Authors: Flore Depeint, George Tzortzis, Jelena Vulevic, Kerry I'anson, Glenn R. GibsonAbstract:Background: Galactooligosaccharides are selectively fermented by the beneficial member of the colonic microflora contributing to the health of the host. Objective: We assessed the prebiotic potential of a novel galactooligosaccharide produced through the action of -galactosidases, originating from a probiotic Bifidobacterium bifidum strain, against a galactooligosaccharide produced through the action of an industrial -galactosidase and a placebo. Design: Fifty-nine healthy human volunteers participated in this study. Initially, the effect of the matrix on the prebiotic properties of a commercially available galactooligosaccharide (7 g/d) was assessed during 7-d treatment periods with a 7-d washout period in between. During the second phase, 30 volunteers were assigned to a sequence of treatments (7 d) differing in the amount of the novel galactooligosaccharide (0, 3.6, or 7 g/d). Stools were recovered before and after each intervention, and bacteria numbers were determined by fluorescent in situ hybridization. Results: Addition of the novel galactooligosaccharide mixture significantly increased the bifidobacterial population ratio compared with the placebo (P 0.05), whereas 7 g/d of the novel galactooligosaccharide significantly increased the bifidobacterial ratio compared with the commercial galactooligosaccharide (P 0.05). Moreover, a significant relation (P 0.001) between the bifidobacteria proportion and the novel galactooligosaccharide dose (0, 3.6, and 7 g/d) was observed. This relation was similar to the effect of the novel galactooligosaccharide on the prebiotic index of each dose. Conclusions: This study showed that galactooligosaccharide mixtures produced with different -galactosidases show different prebiotic properties and that, by using enzymes originating from bifidobacterial species, an increase in the bifidogenic properties of the prebiotic product is achievable. Am J Clin Nutr 2008;87: 785–91.
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Synthesis of prebiotic Galactooligosaccharides using whole cells of a novel strain, Bifidobacterium bifidum NCIMB 41171
Applied Microbiology and Biotechnology, 2005Co-Authors: George Tzortzis, Athanasios K. Goulas, Glenn R. GibsonAbstract:A novel strain of Bifidobacterium bifidum NCIMB 41171, isolated from a faecal sample from a healthy human volunteer and able to express β-galactosidase activity, was used in synthesis reactions for the production of galactooligosaccharide from lactose. The β-galactosidase activity of whole bifidobacterial cells showed an optimum activity at pH 6.8–7.0 and 40°C. The transgalactosylation activity of the B. bifidum cells from 50% (w/w) lactose resulted in a galactooligosaccharide mixture (20% w/w) comprising (w/w): 25% disaccharides, 35% trisaccharides, 25% tetrasaccharides and 15% pentasaccharides. Using different initial lactose concentrations, the conversion rate to Galactooligosaccharides was maximum (35%) when 55% (w/w) lactose was used. In fermentation experiments, B. bifidum showed an increased preference towards the produced galactooligosaccharide mixture, displaying higher growth rate and short-chain fatty acid production when compared with commercially available oligosaccharides.
Glaucia Maria Pastore - One of the best experts on this subject based on the ideXlab platform.
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Sequential optimization approach for prebiotic Galactooligosaccharides synthesis by Pseudozyma tsukubaensis and Pichia kluyveri
LWT - Food Science and Technology, 2015Co-Authors: Ana Elizabeth Cavalcante Fai, Ana Paula Resende Simiqueli, Gislaine Ghiselli, Glaucia Maria PastoreAbstract:Abstract Synthesis of the prebiotic Galactooligosaccharides from lactose fermentation by Pseudozyma tsukubaensis and Pichia kluyveri was investigated. In this study, a sequential strategy of two experimental designs was used to optimize Galactooligosaccharides production. First, Plackett-Burman screening design was applied to evaluate the effects of lactose, yeast extract, urea concentration, inoculum concentration, pH and agitation rate on the response of Galactooligosaccharides yield synthesized by both yeasts. The preliminary Plackett-Burman design allowed the identification of the pH and urea concentration as statistically significant variables in the range studied. In order to find the optimal conditions for Galactooligosaccharides synthesis, a central composite rotational design was employed. The independent variables were lactose, yeast extract and urea concentrations, and the response taken into account was Galactooligosaccharides yield produced by P. tsukubaensis . The optimized condition for this prebiotic synthesis was: lactose, yeast extract and urea at concentrations of 26.0, 0.8 and 1.8 g/100 mL, respectively. Under the optimized and validated conditions, the transgalactosylation activity of P. tsukubaensis resulted in GOS yield of 28.35 GOS (g)/100 g of lactose at 24 h, with a maximum GOS production of 73.71 g/L, and approximately 50 g/100 g of lactose hydrolysis.
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Optimized production of biosurfactant from Pseudozyma tsukubaensis using cassava wastewater and consecutive production of Galactooligosaccharides: An integrated process
Biocatalysis and Agricultural Biotechnology, 2015Co-Authors: Ana Elizabeth Cavalcante Fai, Ana Paula Resende Simiqueli, Gislaine Ghiselli, Cristiano José De Andrade, Glaucia Maria PastoreAbstract:Abstract This study aimed to produce biosurfactant from Pseudozyma tsukubaensis using cassava wastewater and an inoculum (biomass) for Galactooligosaccharides synthesis from lactose as an integrated system. First, the use of cassava wastewater as a low cost culture medium by P. tsukubaensis to produce biomass and biosurfactant was evaluated and optimized. Then, the microbial cells (biomass) obtained from the optimized process were used to produce Galactooligosaccharides from lactose. The optimum conditions for biosurfactant and biomass synthesis were found to be 80% (v/v) of cassava wastewater at 30 °C and 200 rpm for 48 h. The highest concentration of biosurfactant, that is, minimum surface tension value and maximum biomass concentration predicted were experimentally confirmed as 26.87 mN/m and 10.5 g/L, respectively. The biosurfactant obtained showed good thermal (121 °C/1 h), pH (2–11) and ionic strength (0–25% NaCl) stability. Excellent emulsifier activity was also verified, suggesting a potential application in enhanced oil recovery. Galactooligosaccharides synthesized by the Kluyveromyces genus have been extensively investigated, however, few studies have reported transgalactosylation ability by other yeast genera. The transgalactosylation activity of the yeast biomass at optimized conditions from 40% (w/w) lactose resulted in Galactooligosaccharides production of 73.12 g/L and a yield of 18.28% (w/w) at pH 8.0 and 30 °C in 24 h. This research showed the technical feasibility of an integrated process: biosurfactant and GOS production from P. tsukubaensis, which takes advantage of the remarkable metabolism of this microorganism. To the best of our knowledge, this is the first study reporting the potential of P. tsukubaensis to produce two economical biotechnological products of increase interest as an integrated process.
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Production of prebiotic Galactooligosaccharides from lactose by Pseudozyma tsukubaensis and Pichia kluyveri
Biocatalysis and Agricultural Biotechnology, 2014Co-Authors: Ana Elizabeth Cavalcante Fai, Cristiano José De Andrade, Juliana Bueno Da Silva, Murillo Lino Bution, Glaucia Maria PastoreAbstract:Abstract For a long time, yeasts have been used for the production of various biocompounds. New strains may exhibit a variety of benefits and applications to modern and classic biotechnological processing. Pichia kluyveri and Pseudozyma tsukubaensis were isolated from peach (Prunus persica) and nectarine (P. persica var. nucipersica) fruit, respectively, and identified through a molecular approach (D1/D2 28S rDNA) and phylogenetic analysis. The isolated yeasts were tested based on their ability to produce Galactooligosaccharides from lactose using living whole cells. For both selected strains, an in vitro analysis of probiotic properties was carried out. A maximum yield of 14.01% and 15.71% (w/w) Galactooligosaccharides was obtained from a lactose solution reaction (40% w/v) using P. kluyveri and P. tsukubaensis, respectively, at 30 °C, pH 7.0 and 24 h. To the best of our knowledge, this is the first study reporting the potential of P. kluyveri and P. tsukubaensis to produce Galactooligosaccharides from lactose. It was shown that the P. kluyveri strain has desirable probiotic potential using the following parameters: thermotolerance, antibacterial activity against some pathogenic bacterial species and tolerance to acid and bile.
Seyed Hossein Hoseinifar - One of the best experts on this subject based on the ideXlab platform.
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effects of dietary galactooligosaccharide enriched commercial prebiotic on growth performance innate immune response stress resistance intestinal microbiota and digestive enzyme activity in narrow clawed crayfish astacus leptodactylus eschscholtz 182
Aquaculture, 2019Co-Authors: Shiva Nedaei, Ahmad Noori, Alireza Valipour, Ali Asghar Khanipour, Seyed Hossein HoseinifarAbstract:Abstract The present study was carried out to evaluate dietary effects of galactooligosaccharide (GOS) (0, 1, 2 and 3%) on the innate immune response, stress resistance, intestinal microbiota, digestive enzyme activity as well as growth performance of narrow clawed crayfish (Astacus leptodactylus). At the end of a 97-day feeding trial, crayfish fed 2% GOS supplemented diets had significantly higher total haemocyte count (THC), semi-granular cell (SGC) and hyaline cell (HC) counts compared to the other groups (P .05).
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Comparative study of Caspian roach (Rutilus rutilus caspicus) fry gut microbiota modulation following administration of galacto- and fructooligosaccharide prebiotics
University of Isfahan, 2015Co-Authors: Seyed Hossein Hoseinifar, Rudabeh RufchaieAbstract:Introduction: Modulation of intestinal microbiota toward potentially beneficial communities (probiotics) positively affects fish physiology and health status. Different prebiotics showed contradictory effects on intestinal microbiota. The present study investigates the effects of different levels of two prebiotics, galacto- and fructooligosaccharide on intestinal microbiota of Caspian roach fry which is a commercially valuable species of Caspian sea. Materials and methods: The study was performed as a randomized design with 5 treatments and 3 replications in which Caspian roach were fed different levels, 0, 1, and 2% of galacto- and fructooligosaccharide prebiotics for 6 weeks. At the end of the trial culture, analysis of intestinal microbiota include lactic acid bacteria levels, total bacteria as well as proportion of LAB were performed by using MRS agar, Plate count agar media. Results: Administration of different levels of galacto- and fructooligosaccharide had no significant effects on total bacteria of intestinal microbiota (P > 0.05). The lactic acid bacteria levels significantly increased compared to control group following prebiotics administration in diet (P > 0.05). LAB levels in galactooligosaccharide treatment were higher than those of fructooligosaccharide treatment. The highest LAB proportion in intestinal microbiota was observed in roach fed diet which contains 2% galactooligosaccharide (P > 0.05). Discussion and conclusion: The results of the present study revealed that prebiotics can be used for modulation of Caspian roach intestinal microbiota toward beneficial bacterial communities. Also, the results showed that galactooligosaccharide was more efficient than fructooligosaccharide in case of modulation of intestinal microbiota and elevation of LAB levels
Ana Elizabeth Cavalcante Fai - One of the best experts on this subject based on the ideXlab platform.
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Sequential optimization approach for prebiotic Galactooligosaccharides synthesis by Pseudozyma tsukubaensis and Pichia kluyveri
LWT - Food Science and Technology, 2015Co-Authors: Ana Elizabeth Cavalcante Fai, Ana Paula Resende Simiqueli, Gislaine Ghiselli, Glaucia Maria PastoreAbstract:Abstract Synthesis of the prebiotic Galactooligosaccharides from lactose fermentation by Pseudozyma tsukubaensis and Pichia kluyveri was investigated. In this study, a sequential strategy of two experimental designs was used to optimize Galactooligosaccharides production. First, Plackett-Burman screening design was applied to evaluate the effects of lactose, yeast extract, urea concentration, inoculum concentration, pH and agitation rate on the response of Galactooligosaccharides yield synthesized by both yeasts. The preliminary Plackett-Burman design allowed the identification of the pH and urea concentration as statistically significant variables in the range studied. In order to find the optimal conditions for Galactooligosaccharides synthesis, a central composite rotational design was employed. The independent variables were lactose, yeast extract and urea concentrations, and the response taken into account was Galactooligosaccharides yield produced by P. tsukubaensis . The optimized condition for this prebiotic synthesis was: lactose, yeast extract and urea at concentrations of 26.0, 0.8 and 1.8 g/100 mL, respectively. Under the optimized and validated conditions, the transgalactosylation activity of P. tsukubaensis resulted in GOS yield of 28.35 GOS (g)/100 g of lactose at 24 h, with a maximum GOS production of 73.71 g/L, and approximately 50 g/100 g of lactose hydrolysis.
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Optimized production of biosurfactant from Pseudozyma tsukubaensis using cassava wastewater and consecutive production of Galactooligosaccharides: An integrated process
Biocatalysis and Agricultural Biotechnology, 2015Co-Authors: Ana Elizabeth Cavalcante Fai, Ana Paula Resende Simiqueli, Gislaine Ghiselli, Cristiano José De Andrade, Glaucia Maria PastoreAbstract:Abstract This study aimed to produce biosurfactant from Pseudozyma tsukubaensis using cassava wastewater and an inoculum (biomass) for Galactooligosaccharides synthesis from lactose as an integrated system. First, the use of cassava wastewater as a low cost culture medium by P. tsukubaensis to produce biomass and biosurfactant was evaluated and optimized. Then, the microbial cells (biomass) obtained from the optimized process were used to produce Galactooligosaccharides from lactose. The optimum conditions for biosurfactant and biomass synthesis were found to be 80% (v/v) of cassava wastewater at 30 °C and 200 rpm for 48 h. The highest concentration of biosurfactant, that is, minimum surface tension value and maximum biomass concentration predicted were experimentally confirmed as 26.87 mN/m and 10.5 g/L, respectively. The biosurfactant obtained showed good thermal (121 °C/1 h), pH (2–11) and ionic strength (0–25% NaCl) stability. Excellent emulsifier activity was also verified, suggesting a potential application in enhanced oil recovery. Galactooligosaccharides synthesized by the Kluyveromyces genus have been extensively investigated, however, few studies have reported transgalactosylation ability by other yeast genera. The transgalactosylation activity of the yeast biomass at optimized conditions from 40% (w/w) lactose resulted in Galactooligosaccharides production of 73.12 g/L and a yield of 18.28% (w/w) at pH 8.0 and 30 °C in 24 h. This research showed the technical feasibility of an integrated process: biosurfactant and GOS production from P. tsukubaensis, which takes advantage of the remarkable metabolism of this microorganism. To the best of our knowledge, this is the first study reporting the potential of P. tsukubaensis to produce two economical biotechnological products of increase interest as an integrated process.
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Production of prebiotic Galactooligosaccharides from lactose by Pseudozyma tsukubaensis and Pichia kluyveri
Biocatalysis and Agricultural Biotechnology, 2014Co-Authors: Ana Elizabeth Cavalcante Fai, Cristiano José De Andrade, Juliana Bueno Da Silva, Murillo Lino Bution, Glaucia Maria PastoreAbstract:Abstract For a long time, yeasts have been used for the production of various biocompounds. New strains may exhibit a variety of benefits and applications to modern and classic biotechnological processing. Pichia kluyveri and Pseudozyma tsukubaensis were isolated from peach (Prunus persica) and nectarine (P. persica var. nucipersica) fruit, respectively, and identified through a molecular approach (D1/D2 28S rDNA) and phylogenetic analysis. The isolated yeasts were tested based on their ability to produce Galactooligosaccharides from lactose using living whole cells. For both selected strains, an in vitro analysis of probiotic properties was carried out. A maximum yield of 14.01% and 15.71% (w/w) Galactooligosaccharides was obtained from a lactose solution reaction (40% w/v) using P. kluyveri and P. tsukubaensis, respectively, at 30 °C, pH 7.0 and 24 h. To the best of our knowledge, this is the first study reporting the potential of P. kluyveri and P. tsukubaensis to produce Galactooligosaccharides from lactose. It was shown that the P. kluyveri strain has desirable probiotic potential using the following parameters: thermotolerance, antibacterial activity against some pathogenic bacterial species and tolerance to acid and bile.
