Squeezing and phase space coherence are investigated for a bimodal cavity accommodating a two-level atom. The two modes of the cavity are initially in the Barut–Girardello coherent states. This system is studied with the SU(1,1)-algebraic model. Quantum effects are analyzed with the Husimi function under the effect of the intrinsic decoherence. Squeezing, quantum mixedness, and the phase information, which are affected by the system parameters, exalt a richer structure dynamic in the presence of the intrinsic decoherence.

In this paper, we provide an analytical description of the intrinsic noise model of the two-mode cavity, containing a single two-level atom through su(1,1)-algebraic treatment. Each field interacts with the qubit through a fourphoton process and is assumed initially in Barut-Girardello coherent state. The Atomic Quantum Fisher information (AQFI), atomic entropy and the correlation function are analyzed under the effects of the intrinsic damping and the superposition of the initial generalized Barut-Girardello Coherent States (B-GCS). Under the nonlinear interactions, the AQFI has irregular oscillatory behavior that depends on the superposition of the BGCS. Due to the high nonlinear interactions, the damping work with a very small value and leads to the degradation of the AQFI. This degradation can be enhanced in the case of the even B-GCS. The generated entanglement and mixedness of the atomic entropy are explored, they are very sensitive to the physical parameters of the intrinsic damping, the detuning and the initial cavity state. It is found that the second-order correlation depends on the mean photon number, the superposition of the B-GCS, and the damping. For the small value of the mean photon number and with the damping, the sub-Poissonian effects increase with the BGCS, while the super-Poissonian behavior increases with its even states. For the off-resonant case, the frequency, the regularity and stability of the NSOC function, the atomic entropy and the AQFI are enhanced

In this study, an analytical solution for a novel intrinsic noise model represented by two coupled qubits inside a cavity, the Su.1; 1/ and Su.2/ Lie group, is investigated. Each qubit interacts with a two-mode parametric amplifier through a nondegenerate two-photon process when the two-mode system is initially in a superposition of a generalized Barut–Girardello coherent state. The nonlinearity of the interaction and the initial two-mode fields lead to the generation of different quantum correlations (QCs), which are measured by log-negativity, uncertaintyinduced nonlocality, and local quantum uncertainty (LQU). The generatedQCof the interaction depends not only on the two-qubit coupling but also on the intrinsic noise and the initial coherent intensity. Our results show that the ability of the two-qubit coupling to protect and enhance the robustness and generation of the QCs depends on the superposition and the coherent intensity of the initial Su.1; 1/ state. Furthermore, the sudden birth and death of the log-negativity and the sudden variations of the LQU depend on the intrinsic noise and the two-qubit coupling.

We explore the phase space quantum effects, quantum coherence and non-classicality, for two coupled identical qubits with intrinsic decoherence. The two qubits are in a nonlinear interaction with a quantum field via an intensity-dependent coupling. We investigate the non-classicality via the Wigner functions. We also study the phase space information and the quantum coherence via the Q-function, Wehrl density, and Wehrl entropy. It is found that the robustness of the non-classicality for the superposition of coherent states, is highly sensitive to the coupling constants. The phase space quantum information and the matter-light quantum coherence can be controlled by the two-qubit coupling, initial cavity-field and the intrinsic decoherence

Abstract 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

Abstract 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

Abstract 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

Abstract 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

Abstract. Oyster mushrooms (Pleurotus spp.) can bioconvert lignocellulosic residues due to the secretion of extracellular enzymes. The production of hydrolytic and oxidative enzymes by five Pleurotus spp. (P. ostreatus, P. columbinus, P. pulmonarius, P. sajor-caju, and P. floridanus), developed in the solid and liquid state of fermentation using three agro-wastes (rice straw, sugarcane bagasse, and cotton waste), as substrate was evaluated in this work. The total nitrogen and potassium percentage were the highest in the case of rice straw, (0.96% and 0.60%). Also, the biological efficiency (BE), from these results, was the highest in the case of P. sajor-caju and P. columbinus recorded 64.4% on rice straw. It was observed that the submerged liquid fermentation (SmF) was suitable for the growth of all Pleurotus species. Also, the high value of enzymatic activity was determined through this study was, higher in the submerged liquid fermentation SmF, than those produced during solid-state culture (SSF). Among proteolytic enzymes, protease produced by the five Pleurotus spp. presenting the highest enzymatic activity (23.80 U/mL) on SmF and (22.56 U/mg) on SSF. Considering the oxidative enzymes, laccase produced, the highest value (1.99 U/mL) of laccase activity of filtrate was estimated from P. ostreatus cultivated on sugarcane bagasse of SmF. Low enzyme level (0.39 U/mg) was manganese peroxidase, obtained from P. floridanus cultivated on the cotton waste of SSF. The enzymatic levels of α-amylase, β-amylase, cellulose, cellobiohydrolase, laccase, and lignin peroxidase were from 2.9-0.50 U/mL.

Abstract. Oyster mushrooms (Pleurotus spp.) can bioconvert lignocellulosic residues due to the secretion of extracellular enzymes. The production of hydrolytic and oxidative enzymes by five Pleurotus spp. (P. ostreatus, P. columbinus, P. pulmonarius, P. sajor-caju, and P. floridanus), developed in the solid and liquid state of fermentation using three agro-wastes (rice straw, sugarcane bagasse, and cotton waste), as substrate was evaluated in this work. The total nitrogen and potassium percentage were the highest in the case of rice straw, (0.96% and 0.60%). Also, the biological efficiency (BE), from these results, was the highest in the case of P. sajor-caju and P. columbinus recorded 64.4% on rice straw. It was observed that the submerged liquid fermentation (SmF) was suitable for the growth of all Pleurotus species. Also, the high value of enzymatic activity was determined through this study was, higher in the submerged liquid fermentation SmF, than those produced during solid-state culture (SSF). Among proteolytic enzymes, protease produced by the five Pleurotus spp. presenting the highest enzymatic activity (23.80 U/mL) on SmF and (22.56 U/mg) on SSF. Considering the oxidative enzymes, laccase produced, the highest value (1.99 U/mL) of laccase activity of filtrate was estimated from P. ostreatus cultivated on sugarcane bagasse of SmF. Low enzyme level (0.39 U/mg) was manganese peroxidase, obtained from P. floridanus cultivated on the cotton waste of SSF. The enzymatic levels of α-amylase, β-amylase, cellulose, cellobiohydrolase, laccase, and lignin peroxidase were from 2.9-0.50 U/mL.