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Supercritical fluid extrusion (SCFX) with carbon dioxide was used to enhance the functionality of whey protein concentrate containing 80% protein by weight (WPC80) at two (3.0 and 5.4) pH values. Different levels of oil (20, 40, 60, and 80% by weight) and functionalized whey protein (f‐WPC80; 1, 2, and 4% by weight) were used to make emulsions and quantify their characteristics such as emulsion activity index, creaming index, droplet size, and viscosity. Unextruded whey protein (c‐WPC80) and commercial sodium caseinate (NaCas) were used as controls. Results showed that gel‐like emulsions with uniform droplet size distributions were formed by f‐WPC80 (4% by weight) with 80% (by weight) oil which was stable over 3 months of storage at room temperature. Compared to emulsions formed by control c‐WPC80, the f‐WPC80 emulsions exhibited higher viscosity and shear thinning behavior. The minimum protein required for stable emulsion formation (with 80% oil) was found to be 2% by weight for f‐WPC80 and NaCas and 4% by weight in the case of c‐WPC80. The functionalized whey protein provided a better emulsion at low concentrations with good stability at room temperature and may be used as a replacement of sodium caseinate to make nutritionally superior products. Practical applications Present study showed that functionalized Whey protein concentrate (80% protein) f‐WPC80 was produced by the process of Supercritical carbon dioxide assisted extrusion which changed the structure of native protein. Two functionalized products (with pH 3.0 and 5.4) were obtained in this way. These functionalized proteins formed better oil‐in‐water emulsions which were stable against creaming and sedimentation as compared to emulsions stabilized by native WPC80 and sodium caseinate at very small concentration of protein used. Therefore it is concluded that f‐WPC80 can cover a range of food emulsions where different pH values are required. Lesser amount of stabilizer will be used commercially for emulsions. These functionalized WPC80 products may be used as a replacement of sodium caseinate to make nutritionally superior products with pH 3.0 and 5.4.

Stevioside is a natural acaloric stevioside being extracted from Stevia rebaudiana but 150-200 times sweeter than sucrose. In present study a comparison was made between conventional methods of extraction i.e., soxhlet extraction and cold maceration and modern method of extraction i.e., microwave assisted extraction for the rapid and efficient extraction of stevioside from Stevia rebaudiana. It was found that microwave assisted extraction gave the maximum amount of stevioside (0.7658 mg/g of dry leaf powder) while using lesser time of extraction (120 seconds) with a little amount of solvent used (10 mL/g). Another advantage of the method was the maximum quantity of stevioside was obtained from water which is an environment friendly solvent.

The ability of microorganisms to generate resistance outcompetes with the generation of new and efficient antibiotics. Therefore, it is critically required to develop novel antibiotic agents and treatments to control bacterial infections. Green synthesized metallic and metal oxide nanoparticles are considered as the potential means to target bacteria as an alternative to antibiotics. Nanoconjugates have also attracted attention because of their increased biological activity as compared to free antibiotics. In the present investigation, silver nanoparticles (AgNPs), zinc oxide nanoparticles (ZnO NPs), copper oxide nanoparticles (CuO NPs), and iron oxide nanoparticles (FeO NPs) have been synthesized by using leaf extract of Ricinus communis. Characterization of nanoparticles was done by using UV–Vis Spectroscopy, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Energy Dispersive X-Ray Analyzer, X-ray Diffraction Analysis, and Dynamic Light Scattering Particle Size Analyzer. Interestingly, Streptomycin when combined with AgNPs, ZnO NPs, CuO NPs, and FeO NPs showed enhanced antibacterial activity against clinical isolates of S. aureus which suggested synergism between the nanoparticles and antibiotics. The highest enhanced antibacterial potential of Streptomycin was observed in conjugation with ZnO NPs (11 ± 0.5 mm) against S. aureus. Minimum inhibitory concentration of conjugates of AgNPs, ZnO NPs, CuO NPs, and FeO NPs with streptomycin against S. aureus was found to be 3.12, 2.5,10, and 12.5 μg/mL respectively. The considerable point of the present investigation is that S. aureus, which was resistant to streptomycin becomes highly susceptible to the same antibiotic when combined with nanoparticles. This particular observation opens up windows to mitigate the current crisis due to antibiotic resistance to combat antimicrobial infections efficiently.