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This work investigated the reduction of bovine whey proteins antigenicity by ultrasonic pretreatment and microbial fermentation. Firstly, bovine whey proteins was pretreated by ultrasonic techniques, and its secondary structure was detected by circular dichroism. The pretreated whey proteins was used as the fermentation substrate by Kluyveromyces marxianus for microbial transformation. The single factor design and Box-Behnken Design (BBD) were carried out with the aim to optimize culture temperature, initial pH, inoculum volume and rotation speed. After optimization process, culture temperature, initial pH, inoculum volume and rotation speed were determined. Under culture temperature 35 °C, pH 7.25, inoculum level 10% and shaking speed 150 rpm, the α-LA and β-LG antigenicity in bovine whey proteins were reduced by 29% and 53%, respectively. The findings showed that combined with microbial fermentation for hydrolysis of whey proteins, ultrasonic pretreatment can be used in order to produce hypoallergenic bovine whey proteins.

The task of mitigating climate change is usually allocated through administrative regions in China. In order to put pressure on regions that perform poorly in mitigating climate changes and highlight regions with best-practice climate policies, this study explored a method to assess regional efforts on climate change mitigation at the sub-national level. A climate change mitigation index (CCMI) was developed with 15 objective indicators, which were divided into four categories, namely, emissions, efficiency, non-fossil energy, and climate policy. The indicators’ current level and recent development were measured for the first three categories. The index was applied to assess China’s provincial performance in climate protection based on the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. Empirical results show that the middle Yangtze River area and southern coastal area perform better than other areas in mitigating climate change. The average performance of the northwest area in China is the worst. In addition, climate change mitigation performance has a negative linear correlation with energy self-sufficiency ratio but does not have a significant linear correlation with social development level. Therefore, regional resource endowments had better be paid much more attention in terms of mitigating climate change because regions with good resource endowments in China tend to perform poorly.

Currently, there is no clear and unified understanding about the status quo of China's energy consumption in the building sector. In addition, a considerable underestimation of energy associated with buildings has impeded the effective implementation of measures to improve building energy efficiency of China. Thus, in this paper, we seek to identify the building sector's energy consumption of China by establishing an estimation model of building energy consumption from a life cycle perspective. On the basis of macro-level statistical data and relevant literature, we analyze the activities in each phase and calculate associated energy consumptions throughout buildings’ whole life cycle in China from 2001 to 2013. The results show that China's energy consumption associated with buildings has reached 1.66 billion tons coal equivalent in 2013, with a stable growth rate of 7% annually since 2001. Buildings’ life-cycle energy has approximately accounted for 43% of China's total energy consumption for recent three years (2011–2013). What's more, energy consumption in buildings’ operation phase has been salient, accounting for over 20% of China's total energy consumption. More focus should be drawn on energy efficiency in building material production phase and energy consumed in China's rural residential buildings as both have been significantly neglected.

The aim of this study is to develop an ionic liquid-containing system for efficient production of betulinic acid by cultured cells Armillaria luteo-virens Sacc ZJUQH100-6. Several parameters affecting betulinic acid formation in the IL-containing system were investigated. The addition of [EMIM][BF4] in hexane-containing reaction medium gave rise to better betulinic acid formation in comparison with other ILs used. The optimal concentration of IL in IL-containing co-solvent system is 50% (v/v). As a co-substrate, butanol is found to be useful for intracellular betulin-28-monooxygenase synthesis during the whole phase. The concentrations of substrate and resting cells have been found to exert a significant effect on betulinic acid. Moreover, the reaction time in this IL-containing system was less than that in the conventional one. The effect of the constructed IL-containing system on cell membrane structure was comparatively observed. Under the developed IL-containing system, the highest yield of product observed was 11.14% at 18 h, higher than that in monophase aqueous one (P

Co-cultivation was a potential strategy in lignocellulolytic biodegradation with producing high activity enzymes due to their synergistic action. The objective of this study was to investigate the rarely understood effects of co-culturing of two white-rot fungi on lignin-modifying enzymes (LMEs) production. Six species, Bjerkandera adusta, Phlebia radiata, Pleurotus ostreatus, Dichomitus squalens, Hypoxylon fragiforme and Pleurotus eryngii, were cultured in pairs to study the production of LMEs. The paired hyphal interaction observed showed that P. eryngii is not suitable for co-growth. The use of agar plates containing dye RBBR showed elevated decolourisation at the confrontation zone between mycelia. Laccase was significantly stimulated only in the co-culture of P. radiata with D. squalens under submerged cultivation; the highest value was measured after 4 days of incubation (120 U mg(-1)). The improved productions of MnP and LiP were simultaneously observed at the co-culture of P. ostreatus and P. radiata (MnP = 800 nkat L(-1) after 4 days of incubation; LiP = 60 nkat L(-1) after 7 days of incubation), though it was not a good producer of laccase. P. ostreatus appeared to possess specific potential to be used in co-cultured production of LMEs. The phenotype of LMEs production was not only dependent on the species used but also regulated by different nutritions available in the culture medium. The present data will provide evidence for illustrating the regulatory roles of C/N on LMEs production under the co-cultures' circumstances.

Potato starch was esterified with octenyl succinic anhydride (OSA) in aqueous slurry systems and the major factors affecting the esterification were systematically investigated. The physico-chemical properties of the products were determined by means of Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction and a viscosity analyser (VA). The results indicated that suitable parameters for the preparation of OSA starch from potato in aqueous slurry systems were as follows: concentration of starch slurry, 35% (in proportion to water, w/w), reaction period, 3 h, pH of reaction system, 8.0, reaction temperature, 35 °C, amount of OSA, 3% (in proportion to starch, w/w), OSA dilution-fold, 5. The degree of substitution (DS) was 0.017 and the reaction efficiency (RE) was 72 ± 1.8%. FT-IR spectroscopy showed characteristic absorption of the ester carbonyl groups in the OSA starch at 1724 cm −1 . SEM and X-ray diffraction revealed that OSA groups acted by first attacking the surface and some pores formed, but OSA modification caused little change in the crystalline pattern of potato starch (DS 0.045). Apparent pastiness measurement indicated that the starch derivatives gelatinized within a shorter time to achieve higher viscosities over the range of designed concentration of OSA potato starch.

Epidermal growth factor receptor (EGFR) is becoming a perfect target for killing carcinoma cells, especially because of its overexpression on the surface of these cells. Cationic antimicrobial peptides (CAP) have their own special mechanism of membrane-lytic cytotoxicity. In this study, a membrane-lytic immunotoxin (IT), chimeric protein MEGFMEL, was constructed to kill carcinoma cells with EGFR overexpression. This protein is composed of mouse (Mus musculus) epidermal growth factor (MEGF), as the target part, and melittin (MEL), as the cytotoxic part. Using Escherichia coli BL21 and pET30a as expression strain and vector, respectively, 63.45 μg/ml of MEGFMEL (68% purity) was obtained through low-temperature induction of expression and a thawing-freezing purification procedure (without cytolysis). In vitro activity measurement showed that this MEGFMEL significantly induced a lethal effect on A431 carcinoma cells overexpressing EGFR on the surface, with an LD50 value 52.6 μg/ml. The results suggest that the use of CAP as the toxin in the construction of unique membrane-lytic ITs aimed at EGFR is feasible.

The tenderization effect of a new elastase from Bacillus sp. EL31410 was investigated on beef meat. Meat tenderization was done by dipping the meat cut in a solution containing proteolytic enzymes after freeze-dehydration. It was found that a marination time of 4 h was enough for enzyme adsorption. The samples were treated for 4 h in different enzyme solutions and then was stored at 4 °C for 24, 48, 72 h, and subjected to texture measurement, sensory evaluations, biochemical analysis and histological observations. A marked decrease in hardness, by texture measurements, was observed in the meats with papain and elastase and higher sensory scores for tenderness were observed in the meats treated with enzymes than in the control. The papain-treated beef meat received the highest score for tenderness, but the scores given for juiciness and taste were lower than that of the control. Rapid increases of fragmentation of myofibrils from the enzyme-treated meat were observed in the first 24 h of storage, especially for papain-treated meat. Meantime, elastin of myofibrilar structure was selectively degraded by elastase compared with the control when stored at 4 °C for 48 h as shown by electron microscopy. These findings suggest that Bacillus elastase (EL31410) is a promising substitute for papain as a favourable meat tenderizer.