Flavonoids have a broad spectrum of established positive effects on human and animal health. They find an application in medicine for disease therapy and chemoprevention, whence the interest in flavonoids increases. In addition, they are used in food and cosmetic industries as pigments and biopreservatives. Plants are an inexhaustible source of flavonoids. The most important step of plant raw material processing is extraction and isolation of target compounds. The quality of an extract and efficiency of a procedure are influenced by several factors: Plant material and pre-extracting sample preparation, type of solvent, extraction technique, physicochemical conditions, etc. The present overview discusses the common problems and key challenges of the extraction procedures and the different mechanisms for selective extraction of flavonoids from different plant sources. In summary, there is no universal extraction method and each optimized procedure is individual for the respective plants. For an extraction technique to be selective, it must combine an optimal solvent or mixture of solvents with an appropriate technique. Last but not least, its optimization is important for a variety of applications. Moreover, when the selected method needs to be standardized, it must achieve acceptable degree of repeatability and reproducibility.

The design and synthesis of biopolymer nano- and micro-formulations are a new trend with growing priority in scientific research and development in the fields of biomedicine, bioorganic/medicinal chemistry, pharmaceutics, agrochemistry and food industry. This incorporates a vast variety of improved and newly-developed analytical and physico-chemical techniques for green and efficient synthesis. The scope of the present review was to outline the recent advances in the methods for design of novel chitosan micro- and nano-carriers and transporters. Special emphasis is laid on their functionalities and capacity for encapsulation of natural bioactive compounds and controlled in vitro/in vivo release in various biological/physiological media. Expectations for the application of chitosan formulations and chitosan-based hybrid systems are progressively increasing as the knowledge regarding their physical, chemical and biological properties constantly expands. Thus, this review proposes insights on the objective assessment of the capacity, applicability and versatility of newly-designed chitosan-based hybrid systems. A detailed integrative approach, which incorporates the innovative scientific achievements based on complex novel, precise and reliable analytical procedures and methods for qualitative and quantitative morphological, structural, spectral, chemical and biochemical analyses of the bio-precursors and the designed chitosan-carrier micro/nano-hybrid systems, is applied. Sustainable knowledge on the mechanism and methods of natural bioactive substances encapsulation and in vitro/in vivo release is reviewed and discussed.

This study was undertaken to determine the dietary supplements of Zn containing diet on the antioxidant status in chickens experimentally infected withEimeria acervulina. The antioxidant status was monitored via determination of MDA concentrations and erythrocyte SOD and CAT activities, as well as vitamin E, vitamin C, Cu, and Zn in liver, muscle, and serum. The results showed increased MDA (), CAT (), and decreased SOD () in the infected birds. Significant changes in Cu and Zn concentrations and dramatically reduction of vitamin C and E concentrations in the infected chickens were found. The observed deviations in the studied enzymes and nonenzymatic parameters evidence the occurrence of oxidative stress following the infection and impaired antioxidant status of chickens, infected withEimeria acervulina. Our results proved the ameliorating role of CuZn(OH)₃Cl (0.170 g per kg food) againstEimeria acervulina-induced oxidative damage in infected chickens.

The study assessed the applicability of Rhizopus oryzae dead fungi as a biosorbent medium for p‐nitrophenol (p‐NP) removal from aqueous phase. The extent of biosorption was measured through five equilibrium sorption isotherms represented by the Langmuir, Freundlich, Redlich‐Peterson, multilayer and Fritz‐Schlunder models. Linear and nonlinear regression methods were compared to determine the best‐fitting equilibrium model to the experimental data. A detailed error analysis was undertaken to investigate the effect of applying seven error criteria for the determination of the single‐component isotherm parameters. According to the comparison of the error functions and to the estimation of the corrected Akaike information criterion (AIC_C), the Freundlich equation was ranked as the first and the Fritz‐Schlunder as the second best‐fitting models describing the experimental data. The present investigations proved the high efficiency (94%) of Rhizopus Oryzae as an alternative adsorbent for p‐NP removal from aqueous phase and revealed the mechanism of the separation process.

The present review was provoked by the demand of a comprehensive overview on the recent scientific achievements revealing new horizons for advanced applications of organic dyes in service of contemporary medicinal chemistry, pharmacy and biomedicine. The review outlines the basic structural characteristics, physicochemical properties and biological activity of various dye families and suggests modified classifications of dyes according to their structural moieties and bioorganic functionalities serving the necessities of modern analytical chemistry and biochemistry. A major part of the review focuses on the pros and cons of the use of dyes as vectors in bioanalytic assays. The latter is based on comparative analyses of the limitations of some widely applied classical methodologies vs. the advantages and outcomes of the application of newly-designed dye molecules in modern dye-based bioassay techniques.