Proizvodnja egzopolisaharida i sprečavanje sinereze škroba pomoću enkapsuliranoga probiotika Lactobacillus plantarum

Encapsulation of probiotic bacteria with a matrix can increase their survival rate by protecting them from adverse conditions and at the same time without affecting the production of metabolites. An effort has been made to encapsulate the probiotic Lactobacillus plantarum using calcium alginate. Box-Behnken model of response surface methodology (RSM) was employed in the optimization of major encapsulation conditions such as concentration of sodium alginate, calcium chloride and curing time. The second-order quadratic model with the optimum conditions (sodium alginate 2 % (by mass per volume), calcium chloride 0.5 M and curing time 3 h) resulted in a maximum titre of (0.9±0.1) g/L of exopolysaccharides (EPS) at 72 h. The nearness of the coefficient of determination (R²=0.97) to 1 ensures the satisfactory adjustment of the quadratic model to the experimental data. The efficiency of EPS production by encapsulated cells was compared with free cells. The efficacy of secreted EPS in the prevention of syneresis in starch was investigated.Enkapsulacija probiotičkih bakterija povećava mogućnost njihova preživljavanja, štiteći ih od nepovoljnih uvjeta, bez utjecanja na proizvodnju metabolita. U radu se pokušalo enkapsulirati probiotičku bakteriju Lactobacillus plantarum pomoću kalcijeva alginata. Da bi se optimirali glavni uvjeti enkapsulacije, kao što su koncentracija natrijeva alginata, kalcijeva klorida i vrijeme tretiranja, primijenjen je Box-Behnkenov model metode odzivnih površina. Maksimalni titar egzopolisaharida od (0,9±0,1) g/L postignut je nakon 72 sata, i to uvrštavanjem optimalnih uvjeta (koncentracija natrijeva alginata od 2 % (m/V), kalcijeva klorida od 0,5 M i vrijeme tretiranja od 3 sata) u kvadratni model drugoga reda. Koeficijent determinacije od skoro 1 (R²=0,97) osigurao je zadovoljavajuću prilagodbu eksperimentalnih podataka kvadratnom modelu. Učinkovitost proizvodnje egzopolisaharida pomoću enkapsuliranih stanica uspoređena je s onom slobodnih stanica. Također je ispitana učinkovitost izlučenih egzopolisaharida u sprečavanju sinereze škroba

Bisphenol A exposure in Mexico City and risk of prematurity: a pilot nested case control study

Abstract Background Presence of Bisphenol A (BPA) has been documented worldwide in a variety of human biological samples. There is growing evidence that low level BPA exposure may impact placental tissue development and thyroid function in humans. The aim of this present pilot study was to determine urinary concentrations of BPA during the last trimester of pregnancy among a small subset of women in Mexico City, Mexico and relate these concentrations to risk of delivering prematurely. Methods A nested case-control subset of 60 participants in the Early Life Exposure in Mexico to ENvironmental Toxicants (ELEMENT) study in Mexico City, Mexico were selected based on delivering less than or equal to 37 weeks of gestation and greater than 37 weeks of gestation. Third trimester archived spot urine samples were analyzed by online solid phase extraction coupled with high performance liquid chromatography isotope dilution tandem mass spectrometry. Results BPA was detected in 80.0% (N = 48) of the urine samples; total concentrations ranged from < 0.4 μg/L to 6.7 μg/L; uncorrected geometric mean was 1.52 μg/L. The adjusted odds ratio of delivering less than or equal to 37 weeks in relation to specific gravity adjusted third trimester BPA concentration was 1.91 (95%CI 0.93, 3.91, p-value = 0.08). When cases were further restricted to births occurring prior to the 37th week (n = 12), the odds ratio for specific-gravity adjusted BPA was larger and statistically significant (p < 0.05). Conclusions This is the first study to document measurable levels of BPA in the urine of a population of Mexican women. This study also provides preliminary evidence, based on a single spot urine sample collected during the third trimester, that pregnant women who delivered less than or equal to 37 weeks of gestation and prematurely (< 37 weeks) had higher urinary concentrations of BPA compared to women delivering after 37 weeks.http://deepblue.lib.umich.edu/bitstream/2027.42/78251/1/1476-069X-9-62.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78251/2/1476-069X-9-62.pdfPeer Reviewe

Exopolysaccharide Production and Prevention of Syneresis in Starch Using Encapsulated Probiotic Lactobacillus plantarum

Encapsulation of probiotic bacteria with a matrix can increase their survival rate by protecting them from adverse conditions and at the same time without affecting the production of metabolites. An effort has been made to encapsulate the probiotic Lactobacillus plantarum using calcium alginate. Box-Behnken model of response surface methodology (RSM) was employed in the optimization of major encapsulation conditions such as concentration of sodium alginate, calcium chloride and curing time. The second-order quadratic model with the optimum conditions (sodium alginate 2 % (by mass per volume), calcium chloride 0.5 M and curing time 3 h) resulted in a maximum titre of (0.9±0.1) g/L of exopolysaccharides (EPS) at 72 h. The nearness of the coefficient of determination (R²=0.97) to 1 ensures the satisfactory adjustment of the quadratic model to the experimental data. The efficiency of EPS production by encapsulated cells was compared with free cells. The efficacy of secreted EPS in the prevention of syneresis in starch was investigated

Studies on exopolysaccharide production by probiotic Lactic acid bacteria

The thesis mainly discussed the isolation and identification of a probiotic Lactobacillus plantarum, fermentative production of exopolysaccharide by the strain, its purification, structural characterisation and possible applications in food industry and therapeutics. The studies on the probiotic characterization explored the tolerance of the isolated LAB cultures to acid, bile, phenol, salt and mucin binding. These are some of the key factors that could satisfy the criteria for probiotic strains . The important factors required for a high EPS production in submerged fermentation was investigated with a collection of statistical and mathematical approach. Chapter 5 of the thesis explains the structural elucidation of EPS employing spectroscopic and chromatographic techniques. The studies helped in the exploration of the hetero-polysaccharide sequence from L. plantarum MTCC 9510. The thesis also explored the bioactivities of EPS from L. plantarum. As majority of chemical compounds identified as anti-cancerous are toxic to normal cells, the discovery and identification of new safe drugs has become an important goal of research in the biomedical sciences. The thesis has explored the anti-oxidant, anti-tumour and immunomodulating properties of EPS purified from Lactobacillus plantarum. The presence of (1, 3) linkages and its molecular weight presented the EPS with anti-oxidant, anti-tumour and immunomodulating properties under in vitro conditions.Cochin University of science and TechnologyDivision of Biotechnology,National Institute for Interdisciplinary science and Technology, Thiruvananthapura