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In this study, the abundant global textile waste old nylon-6,6 was utilized as a substrate for bacterial cellulose (BC) production by Taonella mepensis WT-6. Briefly, different ratios (dry matter/v, 2.5%, 5%, 10%, or 15%) of nylon-6,6 waste were treated with 15% sulfuric acid for 2, 4, and 6 h, termed as nylon-6,6 acid hydrolysate (NAH). The highest depolymerization efficiency of nylon-6,6 waste was found to be 99.1% at 10% nylon-6,6 after 4 h of acid hydrolysis and released the maximum hexamethylenediamine (HMD), which resulted in a nearly complete degradation of nylon-6,6 to HMD, which was then converted to BC by T. mepensis. The structure and properties of BC films produced from Hestrin and Schramm medium (BC-HS) and nylon-6,6 acid hydrolysate (BC-NAH) media were comparatively studied by Fourier transform infrared spectroscopy (FTIR), mechanical properties, thermogravimetric analysis (TGA), X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and hydrophilicity analysis. The results demonstrated that the structural features of BC-NAH were comparable to BC-HS, suggesting that nylon-6,6 waste could be used as an inexpensive substrate for the cost-effective industrial production of BC. [ABSTRACT FROM AUTHOR]

The process of fabricating chambers is becoming increasingly important for inkjet printhead. However, the majority of present fabrication methods suffer from some problems, such as chamber collapsed, chamber blocked, and the deformation of nozzle plate. This paper develops a novel method for fabricating inkjet chambers by bonding the nozzle plate of SU-8 photoresist with suitable crosslinked degree onto the open microchamber. The softbake temperature of the nozzle plates was optimized for the high bonding strength and the low chamber deformation. The crosslinked degree of the SU-8 photoresist with different exposure dose and post exposure bake (PEB) parameters were calculated based on Fourier transform infrared spectroscopy experiments. The effects of exposure dose and PEB parameters on crosslinked degree of the SU-8 photoresist were analyzed. The influence of crosslinked degree of the SU-8 photoresist on the chamber deformation rate and bonding strength were investigated. The optimized bonding strength of 0.57 MPa and chamber deformation rate of 4.35% were obtained in the final inkjet printhead. Compared with most of the current processing methods, this fabrication technique has great potential due to the decreased chamber deformation rate and the increased bonding strength. [ABSTRACT FROM AUTHOR]

In this study, bacterial cellulose (BC) with antimicrobial properties was produced from waste jasmine flower through sequential fermentations with the fungus Trichoderma reesei and the bacterium Taonella mepensis. In this process, waste jasmine flower was first used for producing cellulase and xylanase with Trichoderma reesei. The activities of cellulase and xylanase in waste jasmine flower reached 66.54 U/g and 107.25 U/g, respectively. Waste jasmine flower was hydrolyzed enzymatically on-site and the resulting hydrolysate was used for BC production. The highest BC yield from supplemented jasmine flower hydrolysate (SJFH) was 4.78 g/L, 2.1 times higher than that from Hestrin and Schramm (HS) medium. BC samples were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, field emission scanning electron microscopy, and antibacterial analysis. The results showed that both the nano structure and thermal property of BC from SJFH medium (BC-JF) were similar to those of BC from HS medium (BC-HS). Furthermore, BC-JF composite displayed excellent antibacterial activity against Staphylococcus aureus. Considering the good biocompatibility of BC-JF to human umbilic vein endothelial cells, this antibacterial BC-JF, which was bioconverted from waste jasmine flower, shows great medical and pharmaceutical application potential. [Display omitted] • Functional bacterial cellulose (BC) was synthesized from waste jasmine flower. • This process is green and cheap. • Jasmine flower hydrolysate significantly improved BC yield. • BC from jasmine flower showed antibacterial activity against S. aureus and E. coli. • BC from jasmine flower demonstrated excellent biocompatibility. [ABSTRACT FROM AUTHOR]

Biomedical polyurethane (BPU) and silk fibroin have similarly molecular architecture in their primary and aggregate structure, both of which have amide bonds and microphase separation, and they have been employed as scaffold materials for biomedical applications. Based on this, as the featured peptide sequence of silkworm silk fibroin, GlycineAlanineGlycineAlanine (GlyAlaGlyAla) tetrapeptide was synthesized by using traditional liquid-phase peptide synthesis method with Boc-protected glycine and alanine as starting materials, and was transformed to its derivative with two amine-terminated functional groups. The derivative was introduced as a chain extender into the backbone to form the hard segment of a silk-inspired PU with urea-linkage. Related measurements show that molecular weight of the synthesized silk-inspired PU ranged from 13,000 to 15,000. Fourier transform infrared (FTIR) absorption bands of Amides I and II are at 1651 cm−1 and 1534 cm−1, and Raman absorption band of Amide III is at 1302 cm−1. UV-Vis absorption peak of the silk-inspired PU is at 266 nm. This new concept and strategy may allow the fabrication of a new class of thermoplastic polyurethane elastomers to mimic the structure and properties of silk fibroin of silkworms and spiders. Information provided by this study may be used to better understand the correlation between the natural and man-made materials. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of BC/BF adsorbent for the first time through co-fermentation. • High PNP adsorption potential of BC/BF composite. • Pore filling, electrostatic interaction, and hydrogen bonding all involved in PNP adsorption. • Renewability and reusability of BC/BF adsorbent. Polyethylene terephthalate (PET) nano-plastics (PNP) is a major source of water pollution which in turn causes health issues in humans. There is no effective method to completely remove PNP from wastewater. In this study, bacterial cellulose (BC)/bacterial flocculant (BF) composite was produced from PNP ammonia hydrolysate through the co-cultivation of Taonella mepensis WT-6 and Diaphorobacter nitroreducens R9. The structural characterization of the BC/BF composite through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and thermal and mechanical analyses demonstrated that the amino-group-rich flocculant produced by the D. nitroreducens R9 was incorporated into the BC network without interfering the self-aggregation of cellulose fibrils. Fast PEP removal was observed in pure and tap water with maximum sorption capacity (Qmax) of 124.65 mg/g and 115.60 mg/g, respectively, whereas least removal was observed for campus lake water with a Qmax value of 84.78 mg/g. A 10 mM SO 4 2− significantly decreased the adsorption capacity to 44.52 mg/g, while 2 mM Ca2+ contributed to the adsorption of PNP with a maximum adsorption capacity of 144.78 mg/g at pH 6.0. The potential adsorption mechanism was investigated through adsorption kinetic studies, isothermal models, and thermodynamics studies. The adsorbed BC/BF was recycled by desorbing PNP with ammonia water, and the eluent could be utilized as a medium for sustainable production of BC/BF. The reusable BC/BF adsorbent produced through the co-culture technique can effectively control PNP pollution. [ABSTRACT FROM AUTHOR]

We describe a novel bioflocculant, MBF-15, which is an exopolysaccharide extracted from the alkaliphilic bacterium Paenibacillus jamilae. The biophysical characteristics of MBF-15 were determined using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. MBF-15 was also evaluated for its biocompatibility by examining its inflammatory, coagulant, and hemostatic properties in vitro and in vivo. Pretreatment of peripheral blood mononuclear cells with MBF-15 inhibited lipopolysaccharide-stimulated expression of inducible nitric oxide synthase, production of nitric oxide, and secretion of pro-inflammatory cytokines, including tumor necrosis factor-α and interleukin-6. In addition, MBF-15 increased both mRNA and protein levels of the anti-inflammatory cytokines transforming growth factor-β and IL-10. The hemocompatibility of MBF-15 was investigated by measuring the hemolysis ratio and clotting times. MBF-15 had high pro-thrombogenic activity but was not hemolytic. In a rat model, MBF-15 showed superior hemostatic properties compared with chitosan. Thus, MBF-15 offers a promising combination of anti-inflammatory and pro-coagulant properties that may be useful for hemostasis in a variety of clinical settings. [ABSTRACT FROM AUTHOR]