Mucins purified from porcine stomachs have gained importance in biomedical applications as they exhibit unique features such as hydrogel formation, lubricity and antivirality. Because commercially available porcine gastric mucins (PGM) are neither gel forming, nor do they reduce friction, a robust purification process for functional mucins from porcine tissue (mainly Muc5AC) is necessary. Based on our former investigations (V. J. Schömig, B. T. Käsdorf, C. Scholz, K. Bidmon, O. Lieleg and S. Berensmeier, RSC Adv., 2016, 6, 44932-44943), we further optimized the established purification process in terms of productivity and overall yield as well as ease of scalability. We therefore introduced a novel extraction method -solid liquid liquid extraction (SLLE) -as an early capture step from homogenized porcine stomach, which combines conventional solid liquid extraction with a second, immiscible solvent, to simultaneously delipidate the tissue and extract hydrophilic proteins into the polar phase. Using Design of Experiments (DoE) the parameters incubation time and ratio of solvent phases (hexane/water) were identified to 3 h and 1/15 for SLLE, respectively. PGM was collected in the polar phase and further purified by size exclusion chromatography and diafiltration. With the homogenization of porcine stomach and the introduction of the SLLE, up to 3570 mg mucin per stomach can be purified, resulting in 55 times more PGM compared to the former published reference process. The productivity of the process was up to 25 mg mucin per stomach and per h, representing an improved process productivity by a factor of 4. Lubricity and gel formation of the purified mucin were retained with the optimized extraction protocol.
Selective sorption of Sb(III) on a microcolumn packed with 1,5-bis(di-2-pyridyl)methylene thiocarbohydrazide immobilized on silica gel (DPTH-gel) has been used for determination of Sb(III). A flow-injection system comprising a microcolumn connected to the tip of the autosampler was used for preconcentration. The sorbed antimony was eluted with nitric acid directly into the graphite furnace and determined by AAS. The detection limit for antimony under the optimum conditions was 0.3 ng mL(-1). This procedure was used for determination of antimony in natural water, soil, vegetation, and a certified sample of a city waste incineration ash (BCR 176).
Compatible solutes are low molecular weight, highly water-soluble and neutrally net-charged molecules with various protective functionalities that accumulate and are produced in microorganisms. Their multi-purpose functionalities, also adaptable in vitro, make them potential components in healthcare and cosmetic products. One promising but insufficiently examined representative of this molecule class is Nγ-acetyl-L-2,4-diaminobutyric acid (γ-NADA), the metabolic precursor of ectoine. Here, we demonstrate the crystallization ability of γ-NADA by using cooling crystallization in aqueous solvents and find that it forms rod-shaped crystals. According to a single crystal structure determination, γ-NADA is orthorhombic with space group P212121 and a = 5.3647(1), b = 8.3652(2), c = 16.9149(5) Å, Z = 4, R1 = 3.48%, wR2 = 7.33% (all data). Additionally, γ-NADA is analyzed via Raman, IR, 1H, and 13C NMR spectroscopy.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.