Ameliorating Direct Blue Dye Degradation Using Trametes versicolor Derived Laccase Enzyme Optimized through Box–Behnken Design (BBD) via Submerged Fermentation

The major intend of this study was to elucidate the laccase production by Trametes versicolor under submerged fermentation using fruit waste peel as substrate. The textile dye was decolorized by the procured crude enzymatic extract using the response surface methodology. The submerged media with organic fruit peel waste extract (jackfruit, pineapple & kaffir) supplemented with gypsum, calcium carbonate, and nutrient broth were considered superior for laccase production. The produced laccase enzyme was used in dye decolorization at the optimum conditions using the Box-Behnken design. Subsequently, the experiment was designed with four variables (dye concentration, pH, temperature & time) with three factors to achieve the maximum direct blue dye decolorization. The highest laccase activity level was obtained from jackfruit peel extract with 3.86U/ml on 15th day at 25oC with pH 5.0 when compared to the other two extracts. The maximum laccase activity with guaiacol was obtained at optimum pH 4 and 40oC. The predicted value was experimentally validated by attaining 81.25% of dye color removal. From the result, the optimum conditions for direct blue color removal were: dye concentration 40ppm, pH 4.0, temperature 40oC at 24 hours. From the results of this study, it was concluded that the jack fruit peel was a more suitable substrate for laccase production. The dye decolorization results were recommended that Box-Behnken design for parameters optimization. The T. versicolor laccase was more proficient for textile dye decolorization. The opportunity was created by using the laccase enzyme for the biological treatment of textile dyeing effluent before discharging into the environment

Role of novel histone modifications in cancer

This article briefly discusses post-translational modifications such as neddylation, sumoylation, glycosylation, phosphorylation, polyADP ribosylation, ubiquitination, and transcriptional regulation

Partial state estimation of LTI systems with multiple constant time-delays

Functional observer design for Multi-Input Multi-Output (MIMO) Linear Time-Invariant (LTI) systems with multiple mixed time delays in the states of the system is addressed. Two structures for the design of a minimum-order observer are considered: 1 - delay-dependent, and 2 - internal-delay independent. The parameters of the delay-dependent observer are designed using the Lyapunov Krasovskii approach. The delay-dependent exponential stability of the observer for a specified convergence rate and delay values is guaranteed upon the feasibility of a set of Linear Matrix Inequalities (LMIs) together with a rank condition. Using the descriptor transformation, a modified Jensen\u27s inequality, and improved Park\u27s inequality, the results can be less conservative than the available functional observer design methods that address LTI systems with single state delay. Furthermore, the necessary and sufficient conditions of the asymptotic stability of the internal-delay independent observer are obtained, which are shown to be independent of delay. Two illustrative numerical examples and simulation studies confirm the validity and highlight the performance of the proposed theoretical achievements

Functional observer design for retarded system with interval time-varying delays

Functional observers are the key solution to numerous practical estimation problems, wherein full-order observers cannot be applied. This paper studies the novel problem of minimum-order functional observer design for time-delay systems with interval time-varying state delays. Moreover, unlike the majority of the existing papers on this topic, which consider either small or unknown delay rates, the delay derivative is assumed to possess an upper bound not limited to be less than one. A new augmented Lyapunov–Krasovskii functional with triple integral terms is employed to derive less conservative delay-dependent sufficient conditions for the stability of the closed-loop observer dynamics, which are expressed in terms of linear matrix inequalities. In addition, contemporary techniques such as Wirtinger-based single- and double-integral inequalities, delay splitting scheme, reciprocally convex approach and convex combination technique, along with the descriptor transformation, are adopted in constructing the new stability criterion that is exploited for obtaining the observer parameters. A genetic-algorithm-based searching schema is proposed to optimally tune a number of weighting parameters in the observer design procedure. Numerical examples and simulation results are demonstrated to confirm the effectiveness and the superiority of the proposed observer design algorithm