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Cordyceps militaris is known for its production of cordycepin, which possesses various biological activities. Silkworm pupae serve as the hosts for Cordyceps militaris , thereby facilitating the synthesis of cordycepin. In this work, the components of silkworm pupae were isolated and used as regulatory factors to promote liquid fermentation of C. militaris to produce cordycepin. Compared with lipids, crude proteins in silkworm pupae are more capable of promoting cordycepin synthesis. Notably, when four proteins (albumin, globulin, gladin and gluten) isolated from crude proteins were added to the fermentation system according to their extraction rates, only globulin had a similar promotional effect as crude protein. In addition, supplementation with 3.31 g/L globulin extended the cordycepin synthesis stage for 6 days, during which the expression level of cns1-4 , genes related to cordycepin synthesis, were significantly up-regulated. Transcriptome analysis of the metabolic pathway of C. militaris after globulin supplementation revealed that the upregulation of glucose metabolism and energy metabolism played a crucial role in extending the synthesis stage of cordycepin to 2.5 times. Silkworm pupae globulin is the main functional factor regulating the synthesis of cordycepin in C. militaris , and is a potential material for industrial production of cordycepin. • Seven kinds of components in silkworm pupae were separated based on Osborne's method. • Silkworm pupae globulin prolonged the cordycepin synthesis stage of C. militaris for 6 days. • Globulin affects cordycepin synthesis through glucose metabolism and energy metabolism. • Adding globulin and sucrose while controlling pH increased cordycepin yield by 280%. • The production of cordycepin using silkworm pupae globulin offers a cost-effective solution. [ABSTRACT FROM AUTHOR]

The platinum loading is randomly distributed within catalyst layers because of the fabrication way, whereas the platinum loading is considered to follow the homogeneous distribution in the traditional catalyst layer model. The cell performance and heat and species transport laws of the fuel cell with platinum loading random distribution within catalyst layers are not yet clear. Therefore, in this work, a two-dimensional, non-isothermal proton exchange membrane fuel cell model considering the two-phase flow and agglomerate structure of catalyst layers is established to simulate the fuel cell having the catalyst layer where platinum loading is random distribution in a way that is closer to the actual structure. The effect of random distribution of platinum loading on the electrical property, species transfer and temperature distribution is analyzed. Results suggest that the randomness influence needs to be considered when the local distributions of parameters are studied and the research accuracy of parameters is relatively high. In contrast with the homogeneous distribution of platinum loading, the cell performance for the normal random distribution and uniform random distribution cases is reduced. The effects of catalyst loading random patterns on cell performance, species and temperature distributions are different, and the decrease of cell performance for the uniform random distribution case is more obvious. Furthermore, the influence degree of randomness on each parameter is different. The distributions of electrochemical reaction rate, oxygen concentration and temperature display random characteristics, while the liquid water saturation distribution is less influenced by randomness and does not show an obvious random change. These findings can provide a reference for the randomness verification in random simulations and deepen the understanding of species and heat transfer laws in the catalyst layer which is closer to the reality to improve the accuracy of fuel cell simulations. [ABSTRACT FROM AUTHOR]

Platinum loading and electrolyte content affect the surface area of electrochemical reaction and proton conductivity, respectively, and protons and oxygen are not uniformly distributed in the catalyst layer. Therefore, platinum loading and electrolyte content can be set to be simultaneous non-uniform distributions to further enhance the species utilization and cell performance. In this study, a non-isothermal, two-dimensional, two-phase fuel cell model is set up and coupled with the catalyst layer agglomerate model. The electrolyte content and platinum loading uneven distributions influence on products and reactants transmission and electrical property is explored. Results indicate that electrolyte volume fraction and platinum loading coinstantaneous graded distribution is more helpful in the species transfer and electrical property improvement. The maximum power density of coinstantaneous graded distribution of platinum content and electrolyte loading along the channel direction is increased by 3.40% compared with the uniform distribution, and is 2.94% higher than the superposition of the maximum power density when the graded distributions of electrolyte volume fraction and platinum loading are separately set. Moreover, the platinum content and electrolyte content gradient distributions do not make liquid water saturation present an evident segment variation along the channel direction, while the opposite is true for oxygen concentration. [ABSTRACT FROM AUTHOR]

The mitigation of eutrophication in the Pearl River Estuary (PRE) has encountered numerous challenges in regards to source control. Herein, the isotope mixing model (SIAR) was used to quantify the primary nitrate sources in the PRE. The results showed that the nitrate levels were significantly higher in the high-flow season than in the low-flow season. Meanwhile, we found the most important nitrate sources were manure and sewage during the high-flow season, with a contribution ratio of 47 % in the low salt area (LSA) and 29 % in the high salt area (HSA). During the low-flow season, the primary nitrate sources were identified as reduced nitrogen fertilizer in the LSA and manure and sewage in the HSA, which accounted for 52 % and 44 %, respectively. Furthermore, we also suggest that a feasible measure might be to control the pollution caused in the PRE by manure and sewage as well as reduced nitrogen fertilizer. [Display omitted] • The nitrate levels in the PRE exist two different areas, with a salinity value of 32 being the distinguishing factor. • The main nitrate sources are manure and sewage during the high-flow season, and which is higher in the LSA than in the HSA. • Reduced nitrogen fertilizer, manure, and sewage are the primary sources of nitrate in the low-flow season. • Runoff, rainfall, and human activity result in significant seasonal variation in nitrate sources in PRE. [ABSTRACT FROM AUTHOR]

• Mulberry anthocyanins were prepared by ATPS biotransformation and HPLC purification. • An ATPS was designed to enhance the conversion of mulberry red pigment from C 3 R to C 3 G. • Whole-cell catalysts containing α -rhamnosidase at the interface of ATPS for easy recovery. • Peak partition collection and post-processing of semi-preparative HPLC was established. • The final purities of C 3 G and C 3 R prepared by semi-preparative HPLC reached 99 %. As a nutritious fruit, mulberry is an ideal source of high-quality cyanidin-3- O -glucoside (C 3 G) with various biological activities. However, the difficult separation process of high-purity C 3 G leads to its high price. To rapidly prepare high-purity C 3 G, cyanidin-3- O -rutinoside is converted to C 3 G by direct hydrolysis of rhamnose bond using a whole-cell catalyst containing α -rhamnosidase. Combined with an aqueous two-phase system, a coupling reaction separation system was established. Two monomers were successfully separated by semi-preparative high performance liquid chromatography (semi-preparative HPLC). The conversion of C 3 G catalyzed by whole-cells in the PEG/Na 2 SO 4 system increased from 47.11 % to 66.56 %, compared with the EtOH/(NH 4) 2 SO 4 system, and the whole-cell activity remained above 50 % after five rounds of reuse. Meanwhile, the purity of C 3 G was increased to 99 % via the semi-preparative HPLC purification and identified by MS. Thus, an integrated process of whole-cell-catalyzed conversion and product peak cutting partition collection provides a novel strategy for efficient biomanufacturing of high-purity C 3 G. [ABSTRACT FROM AUTHOR]

A new fluorogenic substrate Ub-ACC (ubiquitin C-terminal 7-amino-4-carbamoylmethyl-coumarin) was developed for DUB (deubiquitinating enzyme) activity assays. This substrate can be synthesized with higher efficiency than the classical DUB substrate, Ub-AMC (ubiquitin C-terminal 7-amino-4-methylcoumarin). DUB assays using UCH-L3, OTUD2 and USP30 demonstrated that Ub-ACC shows nearly 2-fold higher sensitivity than Ub-AMC. [ABSTRACT FROM AUTHOR]