Wroclaw University of Environmental and Life Sciences

About: Wroclaw University of Environmental and Life Sciences is a education organization based out in Wrocław, Poland. It is known for research contribution in the topics: Population & GNSS applications. The organization has 3108 authors who have published 6672 publications receiving 57774 citations.

The Influence of Aging on the Regenerative Potential of Human Adipose Derived Mesenchymal Stem Cells

Abstract: Tissue regeneration using human adipose derived mesenchymal stem cells (hASCs) has significant potential as a novel treatment for many degenerative bone and joint diseases. Previous studies have established that age negatively affects the proliferation status and the osteogenic and chondrogenic differentiation potential of mesenchymal stem cells. The aim of this study was to assess the age-related maintenance of physiological function and differentiation potential of hASCs in vitro. hASCs were isolated from patients of four different age groups: (1) >20 years (n = 7), (2) >50 years (n = 7), (3) >60 years (n = 7), and (4) >70 years (n = 7). The hASCs were characterized according to the number of fibroblasts colony forming unit (CFU-F), proliferation rate, population doubling time (PDT), and quantified parameters of adipogenic, chondrogenic, and osteogenic differentiation. Compared to younger cells, aged hASCs had decreased proliferation rates, decreased chondrogenic and osteogenic potential, and increased senescent features. A shift in favor of adipogenic differentiation with increased age was also observed. As many bone and joint diseases increase in prevalence with age, it is important to consider the negative influence of age on hASCs viability, proliferation status, and multilineage differentiation potential when considering the potential therapeutic applications of hASCs.

Production of erythritol and mannitol by Yarrowia lipolytica yeast in media containing glycerol

Abstract: Glycerol is a by-product generated in large amounts during the production of biofuels. This study presents an alternative means of crude glycerol valorization through the production of erythritol and mannitol. In a shake-flasks experiment in a buffered medium, nine Yarrowia lipolytica strains were examined for polyols production. Three strains (A UV’1, A-15 and Wratislavia K1) were selected as promising producers of erythritol or/and mannitol and used in bioreactor batch cultures and fed-batch mode. Pure and biodiesel-derived crude glycerol media both supplemented (to 2.5 and 3.25 %) and not-supplemented with NaCl were applied. The best results for erythritol biosynthesis were achieved in medium with crude glycerol supplemented with 2.5 % NaCl. Wratislavia K1 strain produced up to 80.0 g l−1 erythritol with 0.49 g g−1 yield and productivity of 1.0 g l−1 h−1. Erythritol biosynthesis by A UV’1 and A-15 strains was accompanied by the simultaneous production of mannitol (up to 27.6 g l−1). Extracellular as well as intracellular erythritol and mannitol ratios depended on the glycerol used and the presence of NaCl in the medium. The results from this study indicate that NaCl addition to the medium improves erythritol biosynthesis, and simultaneously inhibits mannitol formation.

Citric acid production from glycerol-containing waste of biodiesel industry by Yarrowia lipolytica in batch, repeated batch, and cell recycle regimes

Abstract: Yarrowia lipolytica A-101-122 produces high citric acid (112 g l−1) with a yield of 06 g g−1 and a productivity of 071 g l−1 h−1 during batch cultivation in the medium with glycerol-containing waste of biodiesel industry However, it was observed that the specific citric acid production rate, which was maximal at the beginning of the biosynthesis, gradually decreases in the late production phase and it makes continuation of the process over 100 h pointless The cell recycle and the repeated batch regimes were performed as ways for prolongation of citric acid synthesis by yeast Using cell recycle, the active citric acid biosynthesis (96–107 g l−1) with a yield of 064 g g−1 and a productivity of 142 g l−1 h−1 was prolongated up to 300 h Repeated batch culture remained stable for over 1000 h; the RB variant of 30% feed every 3 days showed the best results: 1242 g l-1 citric acid with a yield of 077 g g-1 and a productivity of 085 g l-1 h-1

Lipid production by the oleaginous yeast Yarrowia lipolytica using industrial by-products under different culture conditions

Abstract: Microbial lipid production using renewable feedstock shows great promise for the biodiesel industry. In this study, the ability of a lipid-engineered Yarrowia lipolytica strain JMY4086 to produce lipids using molasses and crude glycerol under different oxygenation conditions and at different inoculum densities was evaluated in fed-batch cultures. The greatest lipid content, 31% of CDW, was obtained using a low-density inoculum, a constant agitation rate of 800 rpm, and an oxygenation rate of 1.5 L/min. When the strain was cultured for 450 h in a chemostat containing a nitrogen-limited medium (dilution rate of 0.01 h−1; 250 g/L crude glycerol), volumetric lipid productivity was 0.43 g/L/h and biomass yield was 60 g CDW/L. The coefficient of lipid yield to glycerol consumption (Y L/gly) and the coefficient of lipid yield to biomass yield (Y L/X ) were equal to 0.1 and 0.4, respectively. These results indicate that lipids may be produced using renewable feedstock, thus providing a means of decreasing the cost of biodiesel production. Furthermore, using molasses for biomass production and recycling glycerol from the biodiesel industry should allow biolipids to be sustainably produced.