Effect of cultivation conditions on invertase production by hyperproducing Saccharomyces cerevisiae isolates

Abstract

Invertase (b-D-fructofuranoside fructohydrolase, EC 3.2.1.26) finds major uses in confectionery and in the production of invert syrup. In the present study, we report on invertase production by wild cultures of Saccharomyces cerevisiae. The yeast strains were isolated from dates available in a local market. Five hyperproducing yeast strains (>100-fold higher invertase activity) were kinetically analysed for invertase production. Saccharomyces cerevisiae strain GCA-II was found to be a better invertase-yielding strain than all the other isolates. The values of Q p and Y p/s for GCA-II were economical as compared to other Saccharomyces cultures. The effect of sucrose concentration, rate of invertase synthesis, initial pH of fermentation medium and different organic nitrogen sources on the production of invertase under submerged culture conditions was investigated. Optimum concentrations of sucrose, urea and pH were 3, 0.2 (w/v), and 6 respectively. The increase in the enzyme yield obtained after optimization of the cultural conditions was 47.7%.

Effect of C/N Ratio and Media Optimization through Response Surface Methodology on Simultaneous Productions of Intra- and Extracellular Inulinase and Invertase fromAspergillus nigerATCC 20611

“…There was a reduction in pH from 6.5 to 3.0 during intra- and extracellular inulinase and invertase productions, and maximum enzymes production was observed at pH 4.6 (data not shown). The maximum productions of inulinase and invertase were obtained at the end of the logarithmic growth phase [20, 25]. It was an interest to determine inulinase production together with invertase; many microbial preparations of inulinase possess remarkable invertase activity (S) accompanying the inulinase activity (I), where their catalytic activity is described in terms of I/S (Inulin/Sucrose) ratio [25, 26].…”

“…The maximum productions of inulinase and invertase were obtained at the end of the logarithmic growth phase [20, 25]. It was an interest to determine inulinase production together with invertase; many microbial preparations of inulinase possess remarkable invertase activity (S) accompanying the inulinase activity (I), where their catalytic activity is described in terms of I/S (Inulin/Sucrose) ratio [25, 26]. There was a significant positive correlation ( r ) coefficient at P ≤ 0.01 between growth on one side and the production of inulinase ( r = 0.98) and invertase ( r = 0.99) on the other side.…”

“…niger ATCC 20611 (data not shown). The studies claim that surfactants affect the cell membrane permeability [25], might affect cell bound enzymes, and enhance the release of enzymes into the medium [34]. The solubilization of membrane bound proteins and phospholipids by Triton X-100 at higher concentrations causes lethal effects on yeast cells [25].…”

“…The studies claim that surfactants affect the cell membrane permeability [25], might affect cell bound enzymes, and enhance the release of enzymes into the medium [34]. The solubilization of membrane bound proteins and phospholipids by Triton X-100 at higher concentrations causes lethal effects on yeast cells [25]. The previous results showed that intra- and extracellular inulinase and invertase productions and biomass were increased with increase in sucrose, yeast extract, NaNO 3 , Zn +2 , and Triton X-100 up to 10% (w/v), 2.5% (w/v), 2% (w/v), 1.5 mM, and 1% (v/v), respectively.…”

Production and characterization of novel self-assembling biosurfactants from Aspergillus flavus

“…Anthrone assay was applied to determine total sugars (Smyth et al 2010b). Reducing sugars were quantified using DNS reagent (Ikram-ul-Haq et al 2005). Starch content was estimated using modified Lugol's iodine test.…”