Fucoidanase and alginate lyase are promising biocatalysts for several biotechnological applications. The sequentially extracted fucoidan and alginate from the brown macroalgae Sargassum latifolium were used for the optimization of a cost-effective culture medium for fucoidanase and alginate lyase production by the marine fungus Dendryphiella arenaria. Plackett–Burman statistical design was conducted for initial determination of the importance of 11 independent variables on enzyme potentiation, and the significant variables were further optimized using Box–Behnken design. The optimum conditions for fucoidanase production were fucoidan (1.5% w/v), NaCl (1.5%), urea (0.3%), and incubation period (2 days), which gives ~ 4 U mL−1 of crude fucoidanase. While, alginate (1.5% w/v), NaCl (4%), NH4Cl (0.3%), and incubation period (6 days) were the optimum conditions that enhanced alginate lyase production to ~ 24 U mL−1. Additionally, a new protocol for the enzymatic saccharification of fucoidan and alginate was optimized using Box–Behnken design with respect to substrate concentration, enzyme dosage, and temperature. The enzymatic saccharification of citric acid-extracted fucoidan gave a maximum yield of reducing sugar 365 mg g−1 fucoidan, while the alkali-extracted alginate gave 439.66 mg g−1 alginate. The results showed that the two enzymes could be exploited for the efficient production of reducing sugars from fucoidan and alginate, which are the key substrate for producing biofuels from brown macroalgal biomass.

Fucoidanase and alginate lyase are promising biocatalysts for several biotechnological applications. The sequentially extracted fucoidan and alginate from the brown macroalgae Sargassum latifolium were used for the optimization of a cost-effective culture medium for fucoidanase and alginate lyase production by the marine fungus Dendryphiella arenaria. Plackett–Burman statistical design was conducted for initial determination of the importance of 11 independent variables on enzyme potentiation, and the significant variables were further optimized using Box–Behnken design. The optimum conditions for fucoidanase production were fucoidan (1.5% w/v), NaCl (1.5%), urea (0.3%), and incubation period (2 days), which gives ~ 4 U mL−1 of crude fucoidanase. While, alginate (1.5% w/v), NaCl (4%), NH4Cl (0.3%), and incubation period (6 days) were the optimum conditions that enhanced alginate lyase production to ~ 24 U mL−1. Additionally, a new protocol for the enzymatic saccharification of fucoidan and alginate was optimized using Box–Behnken design with respect to substrate concentration, enzyme dosage, and temperature. The enzymatic saccharification of citric acid-extracted fucoidan gave a maximum yield of reducing sugar 365 mg g−1 fucoidan, while the alkali-extracted alginate gave 439.66 mg g−1 alginate. The results showed that the two enzymes could be exploited for the efficient production of reducing sugars from fucoidan and alginate, which are the key substrate for producing biofuels from brown macroalgal biomass.

Fucoidanase is a promising biocatalyst for several biotechnological applications. Crude fucoidanase production by Dendryphiella arenaria was optimized using a natural low-cost medium composed of Cystoseira trinodis and natural seawater. The results showed that seaweed biomass concentration and incubation period were the most significant factors affecting fucoidanase production. At the optimized conditions [seaweed biomass (4.25% w/v), seawater concentration (100% v/v), and incubation period (2 days)], the fucoidanase production was 3.43 U/mL. The crude fucoidanase exhibited a wide pH (3–9) stability with residual activity > 58%. The enzyme showed a good thermostability at 40 and 50 °C with half-lives of 239.02 and 115.52 min, respectively. Several parameters of thermal inactivation kinetics and thermodynamics were calculated, and suggested that the enzyme would be thermostable. Additionally, enzymatic extract containing fucoidanase was used for the enzymatic saccharification of the brown algal biomass in terms of seaweed particle size, solid/liquid ratio, and enzyme dosage. The maximum reducing sugars obtained was 57.11 mg/g. To the best of our knowledge, this is the first report regarding fungal fucoidanase optimization mediated saccharification of a brown seaweed.

Fucoidanase is a promising biocatalyst for several biotechnological applications. Crude fucoidanase production by Dendryphiella arenaria was optimized using a natural low-cost medium composed of Cystoseira trinodis and natural seawater. The results showed that seaweed biomass concentration and incubation period were the most significant factors affecting fucoidanase production. At the optimized conditions [seaweed biomass (4.25% w/v), seawater concentration (100% v/v), and incubation period (2 days)], the fucoidanase production was 3.43 U/mL. The crude fucoidanase exhibited a wide pH (3–9) stability with residual activity > 58%. The enzyme showed a good thermostability at 40 and 50 °C with half-lives of 239.02 and 115.52 min, respectively. Several parameters of thermal inactivation kinetics and thermodynamics were calculated, and suggested that the enzyme would be thermostable. Additionally, enzymatic extract containing fucoidanase was used for the enzymatic saccharification of the brown algal biomass in terms of seaweed particle size, solid/liquid ratio, and enzyme dosage. The maximum reducing sugars obtained was 57.11 mg/g. To the best of our knowledge, this is the first report regarding fungal fucoidanase optimization mediated saccharification of a brown seaweed.

Fucoidanase is a promising biocatalyst for several biotechnological applications. Crude fucoidanase production by Dendryphiella arenaria was optimized using a natural low-cost medium composed of Cystoseira trinodis and natural seawater. The results showed that seaweed biomass concentration and incubation period were the most significant factors affecting fucoidanase production. At the optimized conditions [seaweed biomass (4.25% w/v), seawater concentration (100% v/v), and incubation period (2 days)], the fucoidanase production was 3.43 U/mL. The crude fucoidanase exhibited a wide pH (3–9) stability with residual activity > 58%. The enzyme showed a good thermostability at 40 and 50 °C with half-lives of 239.02 and 115.52 min, respectively. Several parameters of thermal inactivation kinetics and thermodynamics were calculated, and suggested that the enzyme would be thermostable. Additionally, enzymatic extract containing fucoidanase was used for the enzymatic saccharification of the brown algal biomass in terms of seaweed particle size, solid/liquid ratio, and enzyme dosage. The maximum reducing sugars obtained was 57.11 mg/g. To the best of our knowledge, this is the first report regarding fungal fucoidanase optimization mediated saccharification of a brown seaweed.

Fucoidanase is a promising biocatalyst for several biotechnological applications. Crude fucoidanase production by Dendryphiella arenaria was optimized using a natural low-cost medium composed of Cystoseira trinodis and natural seawater. The results showed that seaweed biomass concentration and incubation period were the most significant factors affecting fucoidanase production. At the optimized conditions [seaweed biomass (4.25% w/v), seawater concentration (100% v/v), and incubation period (2 days)], the fucoidanase production was 3.43 U/mL. The crude fucoidanase exhibited a wide pH (3–9) stability with residual activity > 58%. The enzyme showed a good thermostability at 40 and 50 °C with half-lives of 239.02 and 115.52 min, respectively. Several parameters of thermal inactivation kinetics and thermodynamics were calculated, and suggested that the enzyme would be thermostable. Additionally, enzymatic extract containing fucoidanase was used for the enzymatic saccharification of the brown algal biomass in terms of seaweed particle size, solid/liquid ratio, and enzyme dosage. The maximum reducing sugars obtained was 57.11 mg/g. To the best of our knowledge, this is the first report regarding fungal fucoidanase optimization mediated saccharification of a brown seaweed.

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The importance of retinoic acid (RA) for the embryonic and developing systems has been under focus several years ago. The present study aimed to clarify the effect of exogenous RA during development and morphogenesis of the retinal pigment epithelial cells (RPE) of the developing chick embryo after the initial organogeny of the retina. Fertilized eggs of Gallus domesticus were injected with a single dose of 0.5 µg, 1 µg or 2 µg of RA dissolved in 1 µl of dimethylsulphoxide (DMSO). Injections were carried out after three days of incubation. Exogenous Ra in different concentrations was found to affect the morphology of retinal pigment epithelial cells and produced pigment granules in some of these cells in the chick embryo during the period of morphogenesis. The results revealed that RA affected the morphological features and functions of RPE cells where the treatment with different concentrations of RA resulted in flattened cells, increasing the extracellular spaces between RPE cells, inhibiting gap junctional intercellular communication, electron dense cytoplasmic material and organelles, increasing the microvillous projections on the free surface and increasing the frequency of the pigments granules within the RPE cells with changing its localization to be on the vitread side rather than being on the sclerad and lateral sides, It was also found that RA decreased the relative volume of nuclei and increased the relative volume of the nucleoli which was observed in higher concentrations of RA. The teratogenic effect of RA on the RPE cells was limited and restricted to induction of some morphological changes. This might be interpreted as a result f deactivation of RA by the degrading enzymes which are found in the RPE cells in large amounts.

Fuzzy soft separation axioms was introduced by Mahanta and Das ([5]) using the definitions of a `fuzzy soft point' and `the complement of a fuzzy soft point is a fuzzy soft point', and `distinct of fuzzy soft points' in there sense. In this paper we, introduce fuzzy soft separation axioms in terms of the modified definitions of a `fuzzy soft point', the complement of a fuzzy soft point is a fuzzy soft set' and `distinct of fuzzy soft points'([7]). Also, we study some of their properties. Finally, we discuss fuzzy soft topological property for such spaces.

Fuzzy soft separation axioms was introduced by Mahanta and Das ([5]) using the definitions of a `fuzzy soft point' and `the complement of a fuzzy soft point is a fuzzy soft point', and `distinct of fuzzy soft points' in there sense. In this paper we, introduce fuzzy soft separation axioms in terms of the modified definitions of a `fuzzy soft point', the complement of a fuzzy soft point is a fuzzy soft set' and `distinct of fuzzy soft points'([7]). Also, we study some of their properties. Finally, we discuss fuzzy soft topological property for such spaces.