Sugary kefir grains as the inoculum for developing a low sodium isotonic beverage.

The objective of this study was to apply for the first time sugary kefir to produce a new isotonic with low sodium. Additionally, the microbial community profile of grains and fermented kefir was evaluated through metataxonomics. The kefir grains were inoculated into filtered water containing 40 g L-1 sugar at 25 °C for 48 h. Grains and beverage samples were collected at 0, 24, and 48 h for DNA extraction. The grains were separated, and the beverage was used to prepare the isotonic. The isotonic consisted of kefir (85% v/v), pasteurized juice (15% v/v), sodium citrate (0.2 g L-1), sodium chloride (0.427 g L-1), maltodextrin (22 g L-1) and citric acid (0.7 g L-1). The physicochemical and microbiological parameters were performed on days 0, 7, 15, and 30. All isotonic obtained presented sodium content below the commercial control. The presence of lactic acid bacteria and yeasts in all periods evaluated demonstrated the viability of isotonic kefir. Through metataxonomy, the genus Ethanoligenens was described as dominant for the first time in sugary kefir. Furthermore, the microbial diversity in the beverage was higher than that observed in the grains. This study provided a new low sodium isotonic based on sugary kefir for the first time.

Amino acid-based hydrophobic affinity cryogel for protein purification from ora-pro-nobis (Pereskia aculeata Miller) leaves.

The surfaces of the polyacrylamide cryogels were coated with L-tryptophan (cryogel-Trp) or L-phenylalanine (cryogel-Phe) to enhance crude leaf extract-derived ora-pro-nobis (OPN) protein binding via pseudo-specific hydrophobic interactions. Cryogels functionalized with amino acids were prepared and characterized through morphological, hydrodynamic, and thermal analyses. The adsorption capacities of cryogel-Phe and cryogel-Trp were evaluated in terms of type (sodium sulfate or sodium phosphate) and concentration (0.02 or 0.10 mol∙L-1) of saline solution, pH (4.0, 5.5, or 7.0), and NaCl concentration (0.0 or 0.5 mol∙L-1). The cryogel-Phe presented a higher adsorptive capacity, achieving its maximum value (q = 92.53 mg∙g-1) when the crude OPN crude leaf extract was diluted in sodium sulfate 0.02 mol∙L-1 + NaCl 0.50 mol∙L-1, at pH = 7.0. The dilution rate significantly (p < 0.05) affected the recovered protein amount after the adsorption and elution processes, reaching 94.45% when the feedstock solution was prepared with a crude extract 5 times. The zeta potential for the eluted OPN proteins was 5.76 mV (pH = 3.23) for both dilution rates. The secondary structure composition mainly included ß-sheets (46.50%) and α-helices (13.93%). The cryogel-Phe exhibited interconnected pores ranging 20-300 µm in size, with a Young modulus of 1.51 MPa, and thermal degradation started at 230 °C. These results indicate that the cryogel-Phe exhibited satisfactory properties as promising chromatography support for use in high-throughput purification of crude leaf extract-derived OPN proteins.