Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences
Not a member yet
3266 research outputs found
Sort by
Improved mechanical and barrier properties of starch film with reduced graphene oxide modified by SDBS
No full textStarch is regarded as one of the most promising biopolymers to replace the fossil resources. However, due to the poor mechanical properties, high sensitivity to humidity, and low barrier property, the development of starch-based materials has been limited. In this study, they improved the mechanical and barrier properties of starch film with reduced graphene oxide (RGO) modified by sodium dodecyl benzene sulfonate (SDBS). The hydrophilia of modified RGO (r-RGO) was improved and result in a good dispersion in oxidized starch (OS) matrix. The tensile strength of the r-RGO-4/OS film increased to 58.5 MPa which was more than three times of the OS film (17.2 MPa). Besides, both the water vapor and oxygen barrier properties of r-RGO/OS film were improved greatly compared with OS and GO/OS films. Moreover, the r-RGO/OS film could protect against UV light effectively due to its lightproof performance. In conclusion, the r-RGO/OS composite film has great potential applications in packaging industry. (C) 2017 Wiley Periodicals, Inc
Feed-additive probiotics accelerate yet antibiotics delay intestinal microbiota maturation in broiler chicken
No full textBackground: Reducing antibiotics overuse in animal agriculture is one key in combat against the spread of antibiotic resistance. Probiotics are a potential replacement of antibiotics in animal feed; however, it is not clear whether and how probiotics and antibiotics differ in impact on physiology and microbial ecology of host animals. Results: Host phenotype and fecal microbiota of broilers with either antibiotics or probiotics as feed additive were simultaneously sampled at four time points from birth to slaughter and then compared. Probiotic feeding resulted in a lower feed conversion ratio (FCR) and induced the highest level of immunity response, suggesting greater economic benefits in broiler farming. Probiotic use but not antibiotic use recapitulated the characteristics of age-dependent development of gut microbiota in the control group. The maturation of intestinal microbiota was greatly accelerated by probiotic feeding, yet significantly retarded and eventually delayed by antibiotic feeding. LP-8 stimulated the growth of many intestinal Lactobacillus spp. and led to an altered bacterial correlation network where Lactobacillus spp. are negatively correlated with 14 genera and positively linked with none, yet from the start antibiotic feeding featured a less-organized network where such inter-genera interactions were fewer and weaker. Consistently, microbiota-encoded functions as revealed by metagenome sequencing were highly distinct between the two groups. Thus, "intestinal microbiota maturation index" was proposed to quantitatively compare impact of feed additives on animal microecology. Conclusions: Our results reveal a tremendous potential of probiotics as antibiotics' substitute in poultry farming
Response mechanism of the docosahexaenoic acid producer Aurantiochytrium under cold stress
No full textAurantiochytrium is a commercial docosahexaenoic acid (DHA) producer, and its DHA content can be significantly increased under cold stress. Given this response to low temperature, we examined proteomics changes in Aurantiochytrium under cold stress. We detected approximately 700 protein spots using twodimensional gels, whereas using iTRAQ technology, we detected 4650 types of proteins and successfully identified> 53%. The results indicated that cold stress inhibits the cellular energy supply from glycolysis and the TCA cycle, to ensure a sufficient supply of NADPH and ribose for anabolism. In contrast, the pentose phosphate pathway was not affected. With respect to lipid synthesis, low temperature led to a significant downregulation and up-regulation of fatty acid synthase and polyunsaturated fatty acid synthase, respectively, and restricted the protein synthesis of diacylglycerol O-acyltransferase and phospholipid: diacylglycerol acyltransferase. These results show the preferential biosynthesis of polyunsaturated fatty acids and phospholipids by Aurantiochytrium, which collectively serve to increase cell survival rates in cold environments
Synthesis and Adhesive Property Study of a Mussel-Inspired Adhesive Based on Poly(vinyl alcohol) Backbone
No full textIn this study, an effective way is presented to synthesize a mussel-inspired adhesive from two inexpensive commercially available materials: polyvinyl alcohol (PVA) and 3,4-dihydroxybenzoic acid via the esterification reaction and deprotection technology. This bioinspired adhesive exhibits good bonding ability on metal, glass, plastic, and wood, and the maximum bonding strength can be up to 4.0 MPa at dry conditions on glass substrate. Meanwhile, this adhesive can also be used as a wet/underwater adhesive. Such a PVA-based bioinspired adhesive may be used as a potential candidate for applications in industrial field
Li-O-2 Cell with Lil(3-hydroxypropionitrile)(2) as a Redox Mediator: Insight into the Working Mechanism of I- during Charge in Anhydrous Systems
No full textRedox mediators (RMs) have been widely applied to reduce the charge overpotential of nonaqueous lithium-oxygen (Li-O-2) batteries. Among the reported RMs, LiI is under hot debate with lots of controversial reports. However, there is a limited understanding of the charge mechanism of I- in anhydrous Li-O-2 batteries. Here, we study the chemical reactivity between the oxidized state of I- and Li2O2. We confirm that the Li2O2 particles could be chemically oxidized by I-2 rather than I-3(-) species. Furthermore, our work demonstrates that the generated I- from Li2O2 oxidation would combine with I-2 to give I-3(-) species, hindering further oxidation of Li2O2 by I-2. To improve the working efficiency of I- RMs, we introduce a compound LiI(3-hydroxypropionitrile)(2) (LiI(HPN)(2)) with a high binding ability of I-. Compared with LiI, the cell that contained LiI(HPN)(2) shows a significantly increased amount of I-2 species during charge and enhanced Li2O2 oxidation efficiency under the same working conditions
Naphthalene substituents bonded via the beta-position: an extended conjugated moiety can achieve a decent trade-off between optical band gap and open circuit voltage in symmetry-breaking benzodithiophene-based polymer solar cells
No full textBare naphthalene units bonded via the alpha- and beta-positions as side chain substituents on an asymmetric benzodithiophene (BDT) building block were employed in the design of new light-harvesting polymers for the first time. Accordingly, two D-A type polymers, based on naphthyl-substituted BDT as a D-building block and the well-known 4,7-di(thiophen-2-ethylhexyl)-5,6-difluoro-2,1,3-benzothiadiazole (DTffBT) as an acceptor unit, were synthesized. The polymer PBDT beta NPFBT with naphthalene bonded via the beta-position exhibits an appropriate pi-pi distance. The naphthalene rings efficiently broaden the absorption and narrow the optical band gap (E-g(opt)), by extending the degree of pi-conjugation, which is beneficial for capturing more photons and thus improving the short-circuit current density (J(SC)). Meanwhile, PBDT beta NPFBT-based devices also exhibit a desirable high open circuit voltage (V-OC), due to the low saturation dark current density (J(S)) arising from the exactly appropriate pi-pi distance. As a result, the power conversion efficiency (PCE) of 9.80% for the PBDT beta NPFBT/PC71BM-based PSC is the highest efficiency ever obtained among the reported BDT and DTBT backbone photovoltaic polymers. In addition, a PCE of 7.33% was obtained for PBDT beta NPFBT/ITIC without any treatment, which is also impressive for non-fullerene PSCs. Thus, it can be concluded that a naphthyl unit bonded via the beta-position can lead to a better trade-off between E-g(opt) and V-OC, ultimately increasing the PCE dramatically
Characterization and acid-catalysed depolymerization of condensed tannins derived from larch bark
No full textCondensed tannins from larch bark extracts are a natural renewable and eco-friendly material and are potential substitutes for phenolic petrochemicals. However, the wide application of tannin is restricted by its low reactivity. Therefore, the goal of this study was to enhance the reactivity of larch tannin by depolymerization and determine optimal reaction conditions. The structures of larch tannin and depolymerized larch tannin were characterized by Fourier transform infrared (FT-IR) spectroscopy, solid phase C-13-NMR and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. The thermal stability of larch tannin before and after depolymerization was evaluated by thermogravimetric analysis (TGA). The results indicated that the monomeric units of larch tannin were mainly composed of catechin/epicatechin, gallocatechin/epigallocatechin, catechin-gallocatechin esters, and stilbene glucosides. The presence of a catechin gallate dimer that had lost both gallic acid residues and a hydroxy group and a small amount of fisetinidin units were also observed. Additionally, a series of peaks corresponding to oligomers of larch tannin of up to 11 repeating units were observed from the MALDI-TOF MS data. Depolymerization treatment, especially using 2-mercaptoethanol as a nucleophilic reagent, was found to be beneficial to the enhancement of thermal stability. The optimization of the depolymerization reaction allowed the reaction to be completed in two hours, at 60 degrees C, using 2-mercaptoethanol as a nucleophile and 0.1 mol L-1 HCl. Many compounds of molecular weight less than 600 Da, mainly dimers and monomers, were obtained under these reaction conditions
Spatiotemporal variations of inorganic nutrients along the Jiangsu coast, China, and the occurrence of macroalgal blooms (green tides) in the southern Yellow Sea
No full textLarge macroalgal blooms (i.e. green tides of Ulva prolifera) occurred in the southern Yellow Sea, China, yearly from 2007 to 2016. They were among the largest of such outbreaks around the world, and these blooms likely originated along the coast of the Jiangsu Province, China. Understanding the roles of nutrients in the onset of these macroalgal blooms is needed to identify their origin. This study analyzes the spatiotemporal variations in dissolved inorganic nitrogen and phosphorus (DIN and PO4-P) and the N/P ratio along the Jiangsu coast from 1996 to 2014 during late-March to April, the months which corresponds to the pre-bloom period of green tides since 2007. A zone of high DIN and PO4-P concentrations has developed along the Jiangsu coast, between the cities of Sheyang and Nantong, since 1996. There was an 18-year trend of increasing DIN concentrations during the pre-bloom period as well as a positive correlation between the U. prolifera biomass and DIN concentrations. Nutrient inputs from rivers and mariculture in the Jiangsu Province may have provided nitrogen that contributed the magnitude of macroalgal blooms that subsequently spread into the southern Yellow Sea. (C) 2017 Elsevier B.V. All rights reserved
Processes of coastal ecosystem carbon sequestration and approaches for increasing carbon sink
No full textThe oceans are the largest carbon pools on Earth, and play the role of a "buffer" in climate change. Blue carbon, the carbon (mainly organic carbon) captured by marine ecosystems, is one of the important mechanisms of marine carbon storage. Blue carbon was initially recognized only in the form of visible coastal plant carbon sequestration. In fact, microorganisms (phytoplankton, bacteria, archaea, viruses, and protozoa), which did not receive much attention in the past, account for more than 90% of the total marine biomass and are the main contributors to blue carbon. Chinese coastal seas, equivalent to 1/3 of China's total land area, have a huge carbon sink potential needing urgently research and development. In this paper, we focus on the processes and mechanisms of coastal ocean's carbon sequestration and the approaches for increasing that sequestration. We discuss the structures of coastal ecosystems, the processes of carbon cycle, and the mechanisms of carbon sequestration. Using the evolution of coastal ocean's carbon sinks in sedimentary records over geologic times, we also discuss the possible effects of natural processes and anthropogenic activities on marine carbon sinks. Finally, we discuss the prospect of using carbon sequestration engineering for increasing coastal ocean's carbon storage capacity
Rapid degradation of 2,4-dichlorophenoxyacetic acid facilitated by acetate under methanogenic condition
No full textAcetate can be used as an electron donor to stimulate 2,4-dichlorophenoxyacetic acid (2,4-D), which has not been determined under methanogenic condition. This study applied high-throughput sequencing and methanogenic inhibition approaches to investigate the 2,4-D degradation process using the enrichments obtained from paddy soil. Acetate addition significantly promoted 2,4-D degradation, which was 5-fold higher than in the acetate-unsupplemented enrichments in terms of the 2,4-D degradation rate constant. Dechloromonas and Pseudomonas were the dominant 2,4-D degraders. Methanogenic inhibition experiments indicated that the 2,4-D degradation was independent of methanogenesis. It was proposed that the accelerated 2,4-D degradation in the acetate-supplemented enrichment involved an unusual interaction, where members of the acetate oxidizers primarily oxidized acetate and produced H-2. H-2 was utilized by the 2,4-D degraders to degrade 2,4-D, but also partially consumed by the hydrogenotrophic methanogens to produce methane. The findings presented here provide a new strategy for the remediation of 2,4-D-polluted soils. (C) 2017 Elsevier Ltd. All rights reserved