Brink Fletcher (banjosack54)
Laccase, an important oxidoreductase, is widely distributed in various organisms. Termites are known to decompose lignocellulose efficiently with the aid of gut microorganisms. However, few laccases have been characterized from termite or its gut microbes. We aimed to screen the strain capable of degrading lignocellulose from fungus-growing termites. In this study, Bacillus stratosphericus BCMC2 with lignocellulolytic activity was firstly isolated from the hindgut of fungus-growing termite Macrotermes barneyi. see more The laccase gene (BaCotA) was cloned both from the BCMC2 strain and termite intestinal metagenomic DNA. BaCotA was overexpressed in E. coli, and the recombinant BaCotA showed high specific activity (554.1 U/mg). BaCotA was thermostable with an optimum temperature of 70 °C, pH 5.0. Furthermore, BaCotA was resistant to alkali and organic solvents. The enzyme remained more than 70% residual activity at pH 8.0 for 120 min; and the organic solvents such as methanol, ethanol and acetone (10%) had no inhibitory effect on laccase activity. Additionally, BaCotA exhibited efficient decolorization ability towards indigo and crystal violet. The multiple enzymatic properties suggested the presented laccase as a potential candidate for industrial applications. Moreover, this study highlighted that termite intestine is a good resource for either new strains or enzymes.Lycium barbarum polysaccharides (LBP) with different molecular weights (LBP1, LBP2 and LBP3) of 92,441 Da, 7714 Da, and 3188 Da were used as stabilizers and capping agents to prepare uniformly dispersed selenium nanoparticles (SeNPs), and determined the storage stability. In addition, the anti-fatigue activity of LBP-decorated SeNPs with the best stability (LBP1-SeNPs) was estimated by using forced swimming test. The results showed that LBP1-SeNPs exhibited smaller particle size and more excellent stability than those of LBP2-SeNPs and LBP3-SeNPs when the storage time was extended to 30 days, and the average particle size was maintained at about 105.4 nm. The exhaustion swimming time of all tested dose groups of LBP1-SeNPs was significantly longer than the control group (p less then 0.05), and the high-dose group among them was even obviously longer than the positive group (p less then 0.05). The results of glycogen, blood urea nitrogen (BUN), blood lactic acid (BLA), superoxide dismutase (SOD), and malondialdehyde (MDA) levels were further confirmed that LBP1-SeNPs could relieve fatigue by increasing the reserve of glycogen, enhancing antioxidant enzyme levels and regulating metabolic mechanism. These results demonstrated that LBP1-SeNPs could be developed as a potential anti-fatigue nutritional supplement.Post-operative endophthalmitis (POE) is one of the most dreadful complications after intraocular surgery. For cataract surgery patients, both commercially available topical 0.5% levofloxacin and 1% prednisolone acetate (PA) ophthalmic solution require at least 3 to 4 times application daily. In this study, we develop a dual drug delivery system composed of the thermosensitive chitosan/gelatin-based hydrogel containing PA and levofloxacin-loaded nanoparticles (LNPs). LNPs with negative surface charge show the monodisperse (polydispersity index ~0.045), nanosize (~154.7 nm) and sphere-like structure. The optimal concentration of LNPs and PA to corneal epithelial cells was 5 μg/mL and 50 μg/mL, respectively. The developed dual drug delivery system (PAgel-LNPs) could gel at 34 °C within 63 s. The osmolarity of PAgel-LNPs was 301.2 ± 1.5 mOsm/L. PAgel-LNPs showed a sustained-release profile for 7 days. Post-treatment of PAgel-LNPs in TNF-α-damaged corneal epithelial cells could decrease the inflammation (inflammatory genes (TNF-α, IL-6, MMP-3 andMMP-9) and IL-6 production) and cell death. In ex-vivo rabbit model of S. aureus keratitis, the anti-inflammation and anti-bacterial property have been demonstrated. These results suggest that thermosensitive PAgel-LNPs