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Abstract: This study applied co-cultured fungus and bacterium shaking system with optimal medium constituents for fast and maximal decolorization of azo dye. The Aspergillus niger and Bacillus sp. were used to develop a consortium on scrub sponge, which can decolorize reactive red 120 to 90% after 24 h cultivation. Response surface methodology (RSM) was used to investigate the optimal medium composite, 0.1% malt extract and 0.7% KH2PO4, and predicted maximal decolorization achieved 92.68% for 2 h culture and experimental decolorization was 94.5% at initial 50 mg/L concentration. Residual dye was measured by UV–Vis spectrophotometer, and biodegradation metabolites were confirmed by HPLC and FTIR. We revealed a degradation pathway of reactive red 120 with release of 2-aminobenzenesulfonic acid and 3-methanesulfinylbut-3-en-2-one as final metabolite, and terminal degraded metabolites confirmed by phytotoxicity were nontoxic naturally. This study indicated the high potential of fungal–bacterial co-cultured system as an excellent technical innovation for azo dye decolorization. [Copyright &y& Elsevier]

Abstract: We used a hydrophobic micro-textured poly-dimethylsiloxane (PDMS) in the presence of serum protein at 37°C to study the motility of mouse stromal fibroblast on variant (15–100μm) parallel ridge/groove with 30μm depth. In this paper, we observed the temporal changes in cell morphology and locomotion by using time-lapse phase-contrast microscopy. When fibroblasts seeded onto the micro-grooved substrate, almost all of cells concentrated at the bottom of the grooves. Sequentially, the fibroblasts attached and spread on the surface, migrated toward the walls of the grooves, climbed up and down the ridges frequently, apparently, the 30μm depth of groove did not hinder movement across the micro-grooves. Eventually, they stopped proliferating as a result of contact inhibition and formed a confluent monolayer on the ridges almost exclusively, with an orientation parallel to the direction of the ridge/groove. Cellular shape of fibroblast was enhanced with the micro-grooves, the form index of nucleus was 2.6-fold greater than that of cells on smooth surfaces. Further, we found that hydrophobic surfaces are more prone to direct cellular motility in comparison with hydrophilic surfaces. [Copyright &y& Elsevier]

Abstract: Fibroblasts alter their shape, direction of movement, cytoskeleton arrangement, and focal contact when placed upon square array pillars. We prepared pillars of 1μm diameter, separated by 3μm, and having 1, 5, and 10μm heights using substrates displaying identical surface chemistry. When cells seeded initially onto the tops of the pillars, fibroblasts subsequently were immobilized in situ by several pillars that visibly protruded through, but did not pierce, the cell bodies. The cytoplasma then migrated outward with long straight lamella along the interval of the pillars and formed several discrete attachment zones at their side walls – the value of their form index (FI) was as high as 35 – which altered the cellular shape entirely. Most of the cells interacted with the pillar substrate by spreading preferentially in a particular direction, but some of them had the ability to undergo coincident two-direction (x and y) migration; right-angle turn orientations led to the growth of dramatic cellular morphologies. Interestingly, this fibroblast''s behavior variation was gradually in proportion to the pillar height of substrate. Our results confirm that cellular migration and cellular shape are both strongly affected by the geometry of the growth microenvironment. [Copyright &y& Elsevier]