Chen S.,Shanghai Ocean University |
Zhang C.,Shanghai Ocean University |
Xiong Y.,Shanghai Ocean University |
Tian X.,Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization |
And 6 more authors.
Innovative Food Science and Emerging Technologies
We investigated the physiological changes in scallops (Chlamys farreri) during semi-anhydrous living-preservation using metabolomics method to obtain a guiding theory in optimizing the preservation conditions. Glycogen, lactic acid, and crude protein levels were measured in 1-day intervals for 6 days, the median lethal time. The metabolite profiling of scallops after the preservation duration of 10% lethal time (3 days) was achieved based on methyl chloroformate derivation before GC-MS analysis. Carboxyl acids related to respiration (malic, fumaric, and succinic acids), fatty acids (C18:0, C16:0, and C22:6), and amino acids (phenylalanine, glutamic acid, aspartic acid, isoleucine, glycine, pyroglutamic acid, proline, leucine, and 2-aminoadipic acid) were identified as biomarkers. Our results demonstrated that scallops performed an elevated anaerobiosis and depressed aerobiosis, which were not caused by oxygen insufficiency. The switching of energy metabolism patterns and disorder of the osmotic regulation system were also observed, suggesting that oxygen supply is less important for optimizing semi-anhydrous living-preservation. Industrial relevance In China, live aquatic products are far more appreciated by consumers than frozen ones. For example, live scallops are more than ten times as expensive as frozen ones in non-local restaurants. However, there is little profit in providing live scallops instead of frozen scallops, due to the high cost of preservation and transportation. Besides the mortality loss, the high costs of running and building the life-preserving condition are the main costs. Thus, optimizing the preservation conditions can reduce the cost. In our case, we introduced metabolomics instead of non-targeted parameter selecting such as the orthogonal test. Based on the elucidated metabolic pathway, we found that oxygen supplementation is not critical. The high cost of building and running oxygen-supplying module in semi-anhydrous living-preservation can be eliminated. © 2015 Elsevier Ltd. All rights reserved. Source
Liu J.,Shanghai University |
Hu J.,Shanghai University |
Zhong J.,Shanghai University |
Luo J.,Shanghai University |
And 5 more authors.
This research investigated the calcium effect on the anaerobic treatment of fresh leachate in an expanded granular sludge bed (EGSB) bioreactor under mesophilic conditions. The observations show that the bioreactor, inoculated with anaerobic granular sludge, can be started up only in about 40days for the treatment of calcium-containing fresh leachate with chemical oxygen demand (COD) removal efficiency above 90% and organic loading rate up to 72.84kg COD/m3 day. The calcium accumulation onto the granules was monotonically related to the calcium concentration, accounting for 17-18 wt.% of Ca in the suspended solid in the form of calcium carbonate, phosphates/phosphonates and carboxylates. The mineral formation significantly increased the granule settling velocity (by ∼50%) and the suspended solid concentration (by ∼100%). However, the effect of calcium precipitation on the specific methanogenic activity and the CH4 production rate was complex, first positive during the start-up but later on negative. © 2011. Source
Wang P.,Shandong University |
Wang Q.-S.,Shanghai University of Electric Power |
Wang Q.-S.,Shanghai Engineering Research Center |
Ma X.-X.,Shanghai University of Electric Power |
And 5 more authors.
The effect of F and Cl on Mn/TiO2 catalyst for selective catalytic reduction of NO with NH3 was investigated in this study. It was found that the doping of F or Cl has a deactivation effect on Mn/TiO2 catalyst. And the poisoning effect of Cl is more serious than that of F. The characterization results showed that the decrease of BET surface area, the increase of crystallinity, the reduced reducibility and surface acidity, and the decreased concentrations of surface Mn4 + and chemisorbed oxygen should be responsible for the deactivation of Mn/TiO2 catalyst by the doping of F or Cl. © 2015 Elsevier B.V. All rights reserved. Source
Yang N.-Z.,Shanghai University of Electric Power |
Yang N.-Z.,Shanghai Engineering Research Center |
Guo R.-T.,Shanghai University of Electric Power |
Guo R.-T.,Shanghai Engineering Research Center |
And 10 more authors.
The deactivation mechanism of phosphorous on a Mn/TiO2 catalyst for selective catalytic reduction of NO with NH3 was investigated in this study. It was found that the NH3-SCR reaction over the Mn/TiO2 catalyst obeyed the Langmuir-Hinshelwood mechanism. From the characterization results, it could be found the addition of phosphorous on the Mn/TiO2 catalyst would decrease its reducibility and inhibit the adsorption of chemisorbed oxygen and NOx species on its surface. As a result, the P-doped Mn/TiO2 catalyst was deactivated. © 2016 The Royal Society of Chemistry. Source