Production and partial purification of invertase using Cympopogan caecius leaf powder as substrate

Double mutation of Saccharomyces cerevisiae for enhanced β-d-fructofuranosidase fructohydrolase productivity and application of growth kinetics for parametric significance analysis

The kinetics of an extracellular β-d-fructofuranosidase fructohydrolase production by Saccharomyces cerevisiae in a chemically defined medium, i.e., sucrose peptone agar yeast extract at pH 6, was investigated. The wild-type was treated with a chemical mutagen, methyl methane sulfonate. Among the six mutants isolated, methyl methane sulfonate-V was found to be a better enzyme producing strain (52 ± 2.4^a U/mL). The maximum production (74 ± 3.1^a U/mL) was accomplished after at 48 h (68 ± 2.7^a mg/mL protein). The mutants were stabilized at low levels of 5-fluoro-cytocine and the viable ones were further processed for optimization of cultural conditions and nutritional requirements. The sucrose concentration, incubation period and pH were optimized to be 30 g/L, 28 °C, and 6.5, respectively. The methyl methane sulfonate-V exhibited an improvement of over 10 folds in enzyme production when 5 g/L ammonium sulfate was used as a nitrogen source. Thin layer chromatography and high-performance liquid chromatography analysis illustrated the optimal enzyme activity supported by the higher rate of hydrolysis of sucrose into monosaccharides, particularly α-d-glucose and β-d-fructose. The values for Q_p (2 ± 0.12^c U/mL/h) and Y_p/s (4 ± 1.24^b U/g) of the mutant were considerably increased in comparison with other yeast strains (both isolates and viable mutants). The mutant could be exploited for enzyme production over a wider temperature range (26–34 °C), with significantly high enzyme activity (LSD 0.048, HS) at the optimal temperature.

Preliminary Extraction and Identification of the 44.5 kDa Outer Membrane Proteins Isolated from Bovine Fusobacterium necrophorum (AB)

Fusobacterium necrophorum (AB) in the pharynx, respiratory tract, female reproductive tract or urinary system is the causative agent of footrot and hepatic abscesses in animals and acute Lemierre's syndrome in humans. Current methods do not effectively protect animals and humans against F. necrophorum (AB). The outer membrane proteins (OMP) of F. necrophorum (AB) can be used as new material to protect against the diseases induced by F. necrophorum (AB). The aim of this study was to extract OMP and examine the immunogenic response of OMP. The preliminary extraction of OMP of F. necrophorum (AB) was identified by SDS-PAGE and stained by Coomassie Brilliant Blue R-250 (CB B R-250) and silver staining methods. The results showed that only a major band of 44.5 kDa was observed when staining the gel using CB B R-250. This band represented the target protein. In contrast, many small bands were observed by the silver staining method. The OMP also exhibited immune biological activities according to western blot analysis. The brightest band among the multi-banding observed was the OMP. Thus, the OMP was obtained and had immunogenic activity. The results provide a new direction to protect animals and humans against F. necrophorum (AB) in the clinical setting.