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In this study, ethanol was produced via thermal-acid hydrolysis, enzymatic saccharification, and fermentation from the red seaweed Eucheuma denticulatumas a biomass. Also, the removal and further recovery of 5-hydroxymethylfurfural (5-HMF) from hydrolysates were investigated. The thermal-acid hydrolysis produced 38.37 g/L monosaccharides and 6.55 g/L 5-HMF under the optimized condition of 13.7% (w/v) seaweed slurry and 479 mM H2SO4at 121 °C for 54 min. More monosaccharide (6.43 g/L) was obtained from subsequent enzymatic saccharification using 8 U/mL of commercial enzyme C-Tec2 at 45 °C for 36 h. By detoxification, 88.0% of 5-HMF was removed from seaweed hydrolysates using a 1:1 ratio of polyethylenimine (PEI) to 5-HMF (g/g) at a pH of 11.0 for 15 min. Ethanol fermentation of E. denticulatumhydrolysate was performed using wild-type and galactose-adapted Saccharomyces cerevisiae. The ethanol concentration was maximized to 19.56 g/L (YEtOH= 0.43 g/g) by fermenting detoxified E. denticulatumhydrolysate with galactose-adapted S. cerevisiaeFurthermore, for the valuation of 5-HMF (removed from hydrolysate) as a platform chemical, 85.6% of 5-HMF was recovered from the PEI-5-HMF solution by H2SO4at pH 1.0.

Chitosan is a potential renewable marine‐derived resource for bioenergy production. In this study, sulfamic acid, which has dual active sites and a green catalyst, was introduced for the conversion of chitosan, which can be recovered from crustacean shells as food waste of aquatic organisms, into platform chemicals, such as 5‐hydroxymethylfurfural and levulinic acid. By optimization of sulfamic acid‐catalyzed hydrothermal conversion conditions, a 21.48 % 5‐hydroxymethylfurfural yield was achieved under the 200 °C, 3 % (w/w) chitosan, 0.7 M sulfamic acid, 2 min condition. Under the same conditions, a 0.48 % yield of levulinic acid was obtained. These results demonstrate the potential of sulfamic acid and chitosan for applications in the field of bioenergy production. 5‐HMF production: Chitosan is a potential renewable marine‐derived resource for bioenergy production. The catalytic activity of sulfamic acid, which has dual active sites (both Brønsted and Lewis acids) and a green catalyst, is investigated in the conversion of chitosan to 5‐hydroxymethylfurfural (5‐HMF) in aqueous phase. The potential of sulfamic acid and chitosan for applications in the field of bioenergy production is presented.

Background: Atomoxetine has been widely used for the treatment of attention-deficit/ hyperactivity disorder. ATX has additional abilities such as antagonistic effects on the N-methyl-Daspartate receptors (NMDARs) and benefit effects in some animal models of neurological disorders. However, there were few studies regarding protective effects and related mechanisms of ATX against cerebral ischemic insults. Objective: The objective of this study is to investigate neuroprotection of ATX pretreatment and its mechanisms in the hippocampal cornu ammonis 1 (CA1) region following transient global cerebral ischemia in gerbils. Method: Gerbils were subjected to transient global cerebral ischemia induced by the occlusion of common carotid arteries for 5 min. Thirty mg/kg of ATX was administrated intraperitoneally once daily for 3 days before ischemic surgery. To examine neuroprotective effects of ATX, we carried out neuronal nuclear antigen immunohistochemistry and Fluoro-Jade B histofluorescence staining. In addition, immunoreactivities of NMDAR1, NMDAR2A/B, B-cell lymphoma 2 (Bcl-2) and Bcl-2- associated X protein (Bax) are closely related with neuroexcitotoxicity. Results: ATX pretreatment reduced ischemia-induced hyperactivity and protected CA1 pyramidal neurons from ischemia. Pretreatment with ATX significantly attenuated ischemia-induced increases of NMDAR1 and NMDAR2A/B immunoreactivities in the CA1 pyramidal neurons at early time following ischemia. In addition, significant ischemia-induced alterations of Bcl-2 and Bax immunoreactivities were not observed in the ATX-treated group following ischemia. Conclusion: These results show that pretreatment with ATX protected against ischemic neuronal via inhibition of ischemia-induced excitotoxicity at early time following transient global cerebral ischemia.

ABSTRACTWe show that 3-[4-(4-methoxyphenyl)piperazin-1-yl]piperidin-4-yl biphenyl-4-carboxylate (C10), screened out of a chemical library, selectively kills bacterial persisters that tolerate antibiotic treatment but does not affect normal antibiotic-sensitive cells. C10 led persisters to antibiotic-induced cell death by causing reversion of persisters to antibiotic-sensitive cells. This work is the first demonstration in which the eradication of bacterial persisters is based on single-chemical supplementation. The chemical should be versatile in elucidating the mechanism of persistence.

Abstract: Optimal conditions for pilot-scale production of the carboxymethylcellulase (CMCase) by Bacillus amyloliquefaciens DL-3 were investigated. The best carbon and nitrogen sources for the production of CMCase by B. amyloliquefaciens DL-3 were found to be rice hull and peptone and their optimal concentrations were 5.0 and 0.20% (w/v), respectively. Optimal temperature and initial pH for the production of CMCase were 37°C and 6.8. Optimal agitation speed and aeration rate for the production of CMCase were 300 rpm and 1.0 vvm in a 7 L bioreactor, which were different from those for the cell growth of B. amyloliquefaciens DL-3. The highest productions of CMCase by B. amyloliquefaciens DL-3 from 5.0% (w/v) rice hull as a carbon source under optimal conditions in a 7 or 100 L bioreactor were 220 and 367 U/mL, respectively.

Abstract: Thein vitro antimicrobial activity of the marine green algaeUlva lactuca was examined against gram-positive bacteria, gram-negative bacteria, and a fungus. The ethyl-ether extract of algae exhibited a broad-spectrum of antibacterial activity. but not antifungal activity againstCandida albicans. In particular, theU. lactuca extract showed strong activity aganst the bacterium methicillin-resistantStaphylococcus aureus (MRSA). This result confirms the potential use of seaweed extracts as a source of antibacterial compounds or as a health-promoting food for aquaculture.

This study evaluated periodontal repair and biomaterial reaction following implantation of a newly fabricated calcium phosphate chitosan block bone and chitosan membrane on the regeneration of 1- wall intrabony defects in the beagle dogs. The surgical control group received a flap operation only, while experimental group was treated with calcium phosphate chitosan block bone and/or chitosan membrane. All dogs were uneventful healing without any complication. The subjects were sacrificed 8 weeks after the experimental surgery, and a comparative histological and histometric examination was done. Chitosan membrane group significantly enhanced bone regeneration compared to control, CaP-chitosan block bone and combination group. Chitosan membrane remnants were observed in chitosan and combination group, while CaP-chitosan bone materials were resorbed completely. These results suggest that Chitosan membrnae significantly enhanced bone and cementum formation in advanced periodontal defects.

In order to investigate central metabolic changes inBeijerinckia indica, cells were grown on different carbon sources and intracellular flux distributions were studied under varying concentrations of nitrogen. Metabolic fluxes were estimated by combining material balances with extracellular substrate uptake rate, biomass formation rate, and exopolysaccharide (EPS) accumulation rate. Thirty-one metabolic reactions and 30 intracellular metabolites were considered for the flux analysis. The results revealed that most of the carbon source was directed into the Entner-Doudoroff pathway, followed by the recycling of triose-3-phosphate back to Hexose-6-phosphate. The pentose phosphate pathway was operated at a minimal level to supply the precursors for biomass formation. The different metabolic behaviors under varying nitrogen concentrations were observed with flux analysis.

Heliothis zea(HzAM1) insect cells were immobilized in microspheres by sodium-cellulosesulfate (NaCS) and polydiallyldimethylammoniumchloride (PDADMAC). The highest HzAMI cell density was 7.5×107cells/mL in the microspheres. After infection of the immobilized cells byHeliothis zeasingle nuclear polyhedrosis virus (HzSNPV), the highest concentration of HzSNPV (polyhedral inclusion bodies: PIBs) produced was 2.87×1010PIBs/mL in the microspheres.

Hepatocyte spheroids and hepatocyte were immobilized in chitosan/alginate capsules formed by the electrostatic interactions between chitosan and alginate. After encapsulation, there was a 10% decrease in the viability of spheroids due to the exposure of the cells to a pH 6 during the encapsulation process. However, the encapsulated hepatocyte spheroids maintained over 50% viability and liver specific functions for 2 weeks while the encapsulated hepatocytes, free hepatocytes and free hepatocyte spheroids showed low viability and liver specific functions. Therefore, encapsulated hepatocyte spheroid might be applied to the development of a bioartificial liver. [ABSTRACT FROM AUTHOR]

The size of the capsules without O2 limitation and maximum allowable capsule size for different cell densities were calculated by the observable modulus (modified Thiele modulus). When hybridoma (ATCC HB-8852) at 2.5 3 × 105cells/ ml was encapsulated and grown, the cell density reached to 2.6 × 107cells/ml in the 7th day of incubation. The average diameter of the capsule was 2.1mm. The maximum cell density obtained from experiment agreed with the calculated cell density for the given size of the capsules. © Rapid Science Ltd. 1998

The mechanical properties of various differentiated regions of thePorphyra perforata thallus and the effect of LiCl were studied by performing compression and tension tests. Among the various differentiated tissues, the holdfast area was high in its ‘compressive modulus of elasticity’ and ‘tensile modulus of elasticity’, possibly related to its thick matrix. Vegetative non-dividing tissue and vegetative dividing tissue were the most flexible and strong, showing the highest ‘percentage elongation at break’ and ‘tensile strength’. The patch area, which is a transition zone leading to sexually mature tissue, had moderate values of tensile properties. Meanwhile, sexually differentiated male and female tissues had the highest ‘compressive modulus of elasticity’ and lowest tensile properties. Thes tisues tended to crumble easily. Treatments in LiCl, as used for DNA extraction, resulted in a decrease in both ‘compressive modulus of elasticity’ (87%) and ‘tensile modulus of elasticity’ (54%). After treatment of tissue for chromosome staining in a method using LiCl, there was a marked decrease in ‘tensile modulus of elasticity’ (49%), while the ‘compressive modulus of elasticity’ remained unchanged. Such mechanical changes verify the softening effect of LiCl on the seaweedP. perforata tissue.

Biopolymer membrane was prepared using two oppositely charged natural biopolymer. The biopolymer membrane was used for the encapsulation of two hybridoma cell (ATCC CRL-1606, ATCC BH-8852) to produce monoclonal antibodies. In order to reduce the down stream steps, the pore size of the membrane was controlled to retain the monoclonal antibodies in the capsules based on the diffusion experiments with standard proteins. T-flask culture showed cell densities of 8×107cells/mL and 3×107cells/mL, and MAb concentrations of 506 μg/mL and 109 μg/mL for encapsulated ATCC CRL-1606 and HB-8852, respectively. Two liter perfusion culture with encapsulated ATCC HB-8852 was performed to enhance the MAb production. The MAb production of the encapsulated hybridoma increased considerably comparing to the culture using silicone tubing for oxygen transfer.

The exopolysaccharides produced by Z. ramigeramutants were purified by the precipitation with isopropyl alcohol and characterized. The physiological changes of mutant cells resulted the changes in the structure of the product, Zooglan, which could be determined by the measurement of hydrodynamic properties. Zooglans produced by Z. ramigeraSL, SLR and MM1 gave intrinsic viscosities of 14.3 dl/g, 12.2 dl/g and 9.1 dl/g, respectively. The intrinsic viscosity of Zooglan produced by Z. ramigeraMM1/pLEX2F increased to 14.8 dl/g. The hydrodynamic property expressed as the intrinsic viscosity of Zooglans could explain the alteration of the structure of Zooglan synthesized by the physiological activities of the mutant cells.

Microalgae represent a sustainable feedstock for producing biofuels and biomaterials. In this work, levulinic acid (LA) and formic acid (FA) were produced by catalytic hydrothermal conversion of the lipid-extracted residue of Chlorella vulgarisas a renewable bioresource. Following statistical optimization using a Box–Behnken design, yields of 39.27% LA and 22.06% FA were achieved from 5% biomass treated with 0.95 M HCl at 170 °C for 30 min. In conclusion, lipid-extracted microalgal residue and a Brønsted acid catalyst are useful for producing LA and FA.