Screening, optimization and characterization of exopolysaccharides produced by novel strains isolated from Moroccan raw donkey milk
Reda Derdak, Souraya Sakoui, Oana Lelia Pop, Dan Cristian Vodnar, Boutaina Addoum, Abdelhakim Elmakssoudi +4 more
Food Chemistry X
Abstract
Two exopolysaccharides (EPS) producing strains, isolated from raw donkey milk were identified as <i>Leuconostoc mesenteroides</i> SL and <i>Enterococcus viikkiensis</i> N5 using 16S rDNA sequencing. The Box Benheken design exhibited the highest yield of EPS-SL (672.342 mg/L) produced by SL and of EPS-N5 (901 mg/L) produced by N5. The molecular weight was 1.68×10<sup>4</sup> for EPS-SL and 1.55×10<sup>4</sup> Da for EPS-N5. FTIR, NMR and GC-MS analysis showed that the EPS are heteropolysaccharides. The SEM image showed that the EPS-SL was smooth and represented a lotus leaf shape and EPS-N5 revealed a stiff-like, porous appearance and was more compact than EPS-SL. The TGA analyses showed high thermal stability and degradation temperature. Additionally, the two EPSs possessed antibacterial and antioxidant activity, and the EPS-SL had the stronger antioxidant activity. Consequently, these results suggest that the functional and biological properties of EPS-SL and EPS-N5 imply the potential application in the food and pharmaceutical industries.
Extracted Claims
5 claims extracted from this paper into the knowledge graph
EPS-N5 have stiff-like, porous appearance and more compact
“EPS-N5 revealed a stiff-like, porous appearance and was more compact than EPS-SL.”
EPS-SL have smooth and lotus leaf shape
“The SEM image showed that the EPS-SL was smooth and represented a lotus leaf shape.”
EPS-SL and EPS-N5 have high thermal stability and degradation temperature
“The TGA analyses showed high thermal stability and degradation temperature.”