Abstract:Food additives industry plays an important role in the modern food industry as a pillar industry. The development of its research and application mark the status of the national food industry in the world. The widespread attention for food nutrition and safety has indicated that the establishment of a legitimate development and utilization for food additives is a global major issue. Unfortunately，the difference between "food additives" and "chemical additives" has not been well understood for a long period of time due to the incorrect information from the reported food safety incidents. A perceptive and comprehensive review on food additives research was present here summarizing the current status and future trends. Suggestive recommendations were also provided focusing on the key point and developmental direction. This review may guide the stable and healthy development of food additives industry，and catalyze the formation of industrial pattern of food nutrition and health. It may also improve the development of health care system on a national level and promote the construction of harmonious society.

Abstract:Beta-galactosidase solution was obtained through the fermentation of Bacillus circulans SK28.003，and its powder was prepared from the concentration of its solution，salting and precipitation，and freeze drying. To increase the efficiency of transgalatosylation and GOS yields，the optimal reaction conditions，such as initial lactose concentrations，loading amount of the enzyme，temperatures and pH values of the buffer，were determined through single factor and orthogonal experiments. Using the yields of GOS as the evaluation index，the maximum GOS yield was achieved up to 45.5% after 12 h synthesis when the reaction conditions were at 60 ℃，50 g/dL initial lactose concentration，6 U/g lactose in 0.1 M，and sodium phosphate buffer at pH 7.5. Keywords：

Abstract:Corynebacterium crenatum SYPA 5-5 is a industrial strain for L-arginine production. Polyhydroxybutyrate （PHB）is a kind of polymer stored in the bacterial as carbon source and energy. Due to its environment-friendly properties such as biodegradability and biocompatibility，PHB can be made into plastic containers and surgical suture to reduce the white pollution and can be digested easily in the body. It was reported that co-producing PHB and some other industrial valuable compounds，such as succinate，L-glutamate and tryptophan，were possible by introducing PHB metabolic pathways into the cells to influence the intracellular pathways. In this study，a co-produce PHB and L-arginine strain was constructed by introducing the entire phbCAB operon of Ralstonia eutropha H16 into C. crenatum SYPA 5-5. Fermentation were conducted of the start strain and recombinant one，separately，in a 5-L fermentor and relevant fermentation parameters were detected and analysed. The result showed that intracellular PHB（12.8% of DCW） and extracellular L-arginine （43.21 g/L） were obtained and accumulated in the recombinant strain，.In addition，The PHB production also promote the L-arginine yield，which weas increased by 20%.

Abstract:Citrulline，a major precursor of ethyl carbamate in soy sauce，is produced by Pediococcusacidilactici via the arginine deiminase pathway. The effect of cultural conditions to citrulline accumulation of Pediococcus acidilactici BBE 1120 strain isolated from koji was investigated through carbon sources，salt concentration，and amino acids. The mechanism of citrulline accumulation in soy sauce was discussed. The high concentration of NaCl was demonstrated as the key factor to citrulline accumulation of the strain. The types and concentrations of carbohydrates also affected the citrulline accumulation，while insignificant influence was observed with the presence of arginine，citrulline and ornithine. This study is of great importance on the illustration of the accumulation mechanism for ethyl carbamate precursor during soy sauce fermentation.

Abstract:Bacillus subtilis 168 is a safe strain for industrial-scale microbial production of 2，3-butanediol （2，3-BD）. However， a large quantity of by-product of acetoin （AC） is accumulated during 2，3-BD fermentation process. acetoin reductase （ACR） is the key enzyme which catalyzes the conversion of acetoin to 2，3-BD. In this study，in order to improve 2，3-BD production，we firstly cloned the acr gene of acetoin reductase into B. subtilis 168，and then further constructed the recombinant strain B. subtilis 168/pMA5-acr. The results showed that the yield and conversion rate of the 2，3-BD were increased up to 28.62% and 22.87% by the recombinant strain，respectively. Whereas the accumulation of the main by-product of acetoin decreased by 20.01%. Furthermore，the molar yields of by-products of formic acid，acetic acid，lactic acid，and succinate were also decreased.

Abstract:The biodiesel has been successfully produced in a self-designed microwave reactor in laboratory by employing a novel carbon?鄄based acid catalyst prepared via the combination of carbonization and sulfonation process. This work exhibit a potential application of microwave-assisted acid catalyst in biodiesel preparation. The catalyst presented a high efficiency and good stability under microwave treatment with which the reaction was significantly accelerated. The optimization of reaction condition was first studied by a single factor method. The factors which affected the conversion efficiency of biodiesel，such as microwave power density，microwave reaction time，and catalyst amount，were determined accordingly using the response surface analysis. The optimized condition was processed as microwave power density of 1.15 W/mL for 33.33 min with 4.83% catalyst which gave a 90.38% ester yield. This optimized result was consistent with the previous results from the single factor experiments and this model was confirmed with higher reliability and better fitting.

Abstract:The operational performance of Circular Lift Reactor （CLR） anaerobic reactor for gentamicin wastewater treatment was investigated in this study. The CLR anaerobic reactor exhibited a good efficiency in treating gentamicin wastewater. The volume loading rate （VLR） could reach to 5 kg COD/（m3·d） and the effluent with the level of chemical oxygen demand （COD） was within 2 500~3 200 mg/L. The removal efficiency for COD and SS reached as high as 70% and 62%，respectively. The solution pH was kept at 7.8~8.3 and the content of VFA was below 900 mg/L in the stable operation duration，which showed a better stability of CLR anaerobic reactor. However，there was no significant influence to the processing efficiency of CLR anaerobic reactor. The effluent concentration of Ca2+ was maintained at 200~300 mg/L with an average rejection rate of Ca2+ of 74%. In the other side，the high influent concentration of Ca2+ would lead to the calcification of granular sludge and a gradual decline of VSS/TSS，which was more serious in the bottom of the reactor than that in the upper.

Abstract:Cholesterol oxidase is of great value to be applied in medicine，food and agriculture. In this study，cholesterol oxidase from Rhodococcus sp. was constructed into the temperature-induced vector pHsh and then by controlling the culture temperature，the gene was successfully expressed in E.coli without adding inducer. The fermentation optimization of cholesterol oxidase was carried out in the shake flask level. With the optimum condition，the enzyme activity reached 855 U/L. When purified to homogeneity using Ni-NTA，the resulting enzyme had the molecular mass of 55 kDa，the optimal pH 7.0 and temperature 40℃. The enzyme was also stable over a pH range of 5.0~7.0，with t1/2 of 6.9 min at 50 ℃. With cholesterol as substrate at pH 7.5 and 37 ℃，the kinetic parameters Km and kcat/Km were 3.38 mM and 6.09 s-1·mM-1，respectively.

Abstract:A codon-optimized gene Sys1，which encodes a carbonyl reductase，was synthesized，and cloned into an expression plasmid pETDuet-1 with double promoters together with a glucose dehydrogenase-encoding gene Sygdh. The recombinant E. coli BL21/pETDuet-Sygdh-Sys1，expressing the carbonyl reductase and the glucose dehydrogenase together，was constructed by transforming the recombinant plasmid，pETDue-Sygdh-Sys1，into E. coli BL21（DE3）. Using recombinant E. coli cells induced by IPTG as biocatalysts，（R）-2-chloro-1-（3-chlorophenyl）ethanol（（R）-CCE），a chiral drug intermediate，was synthesized by asymmetrically reducing m-chlorophenacyl chloride（m-CPC）. Under the reaction conditions of 30 mmol/L of m-CPC，70 mg/mL of wet recombinant E. coli cells，40 mmol/L of glucose，0.2 mmol/L of NADP+ at pH 7.0 and 40 ℃ for 3 h，the molar yield of（R）-CCE reached 99.0% with an enantiomeric excess（e.e.） value of 100%.

Abstract:The inhibition of bacterial biofilm activity by 30% ethanol elution of Houttuynia cordata was studied. The results showed that the inhibition rates of E.coli and Salmonella typhimurium biofilms were up to 100% when the extract concentration of H. cordata was 4.0 mg/mL. At the same time，the growth of E.coli and S.typhimurium were inhibited by H. cordata extract when its concentrations were 3.0 and 4.0 mg/mL，respectively. Further analysis of its extracts showed that 3，4?鄄dihydroxy benzoic acid，chlorogenic acid，rutin，hyperin，quercetin，and quercetin were its main components. Meanwhile，the effect of preservation of chilled pork by the extracts of H. cordata were also studied. The results exhibited that the microbial content，volatile base nitrogen （TVB-N），pH and SAP turnover rate all had positive effects after the addition of the extractions. The total number of bacteria in per gram of the pork treated by 4.0 mg/mL extract was 5.95 at 15th d，while the control group was 8.01. The results suggested that the extraction of H. cordata had potential applications in chilled pork during storage.

Abstract:Alkaline amylase，which could efficiently hydrolyze starch under alkaline conditions，has been widely used in textile desizing field，detergent industry，and pharmaceutical production. In this study，alkaline amylase from Alkalimonas amylolytica （AmyK） was screened through signal peptide and expressed in Bacillus subtilis WB600. The fermentation condition of the recombinant strain was then optimized. The extracellular AmyK activity of the recombinant B. subtilis could reach a maximal level of 146.86 U/mL with 51 h fermentation mediated by ywbN signal peptide. There was a protein band observed in the culture supernatant which was consistent for the theoretical molecular weight of 60 kDa for AmyK. The fermentation medium was optimize via a single factor test and determined as dextrin of 32 g/L，tryptone of 12 g/L，yeast extract of 24 g/L，KH2PO4 of 2.32 g/L，and K2HPO4·3H2O of 16.43 g/L with pH regulated by 0.2% w/v Na2CO3 after 24 h fermentation. The AmyK activity reached to 640.33 U/mL after 72 h，increasing by 336% when compared with the initial medium，which was the highest yield of alkaline amylase for the reported recombinant B. subtilis strains. This study provided a experimental support for the commercial production of AmyK from fermentation.

Abstract:As the Chinese national specialty，Chinese rice wine has a long history and unique production and fermentation technology，the microbial community and metabolites contribute to the unique flavor during the rice wine brewing. In this study，the metagenome technology was applied to explore the fungi diversity and the GC?鄄MS was used to analyze the volatile flavor compounds in ferment mash of different fermentation periods. The results showed that the ferment mash had higher fungi diversity at the initial stage，22 genera were identified in 0 day. The relative abundance of Aspergillus were all above 90% ，which was much higher as compared with other eukaryotic microorganisms during the fermentation process. The advantageous fungi changed obviously，the genera number decreased at first four days and increased later. The analyzed of volatile flavor compounds showed that the generation of volatile substances were greatly influenced by physical and chemical properties of fermented mash. High acidity，alcohol and low pH reduced the fungi diversity，and lowered the contents of volatile flavor compounds.

Abstract:The effect of six oligosaccharides on the growth of Streptococcus thermophilus and its capability of lactic acid production was investigated by two methods to provide a theoretical basis for the realization of the compatibility use of oligosaccharides and Streptococcus thermophilus for industry production and probiotic products development. One way is to partly or completely replace the lactose composition of M17 culture medium by six commonly used oligosaccharides. Another way is to add six oligosaccharides with various concentrations into M17 culture medium. Six oligosaccharides have been proved to cause a reduction in the growth of Streptococcus thermophilus or even cause growth stop if oligosaccharides completely replaced lactose，while the addition of oligosaccharides was conducive to the growth of Streptococcus thermophilus with the presence of lactose.

Abstract:Heparinase I cloned from Flavobacterium heparinum was widely used in the preparation of LMWH（low molecular weight heparin）. However，the formation of inclusion bodies when expressed in Escherichia coli limits its application in a large scale. In this study，the soluble partner，small ubiquitin-like modifier（SUMO），was fused to the N-terminus of Hep I gene with a C-terminal 6×histidine tag. SDS-PAGE analysis of total protein in bacteria and soluble fractions indicated that the portion of the soluble Heparinase I fused with SUMO to the N-terminus was significantly enhanced. After purified by the nickel-chelate chromatography，the resulting fusion enzyme could be used directly without removing the fusion SUMO tag，which made the wide application of Heparinase I feasible.

Abstract:The expression of laccase gene by Pichia pastoris X33/pGAPZα A-MLcc1 was investigated in a 5 L fermenter. The change trend of laccase activity was consistent with the change trend dry cell weight. The extracellular laccase activity reached the highest value of 47.2 U/L when the yeast X33 entered the stationary phage at 46 h. High-density fermentation in a 5 L fermenter was further investigated and the optimized method for high-level expression was obtained as follows：by adopting dissolved oxygen（DO） feed-back feeding strategy and maintaining DO at 15% to 30% at feeding stage，as well as adding ammonia solution and hydrochloride to maintain pH value at 5 in the fermentation stage，the laccase activity reached 216.3 U/L，which was 4.6 times higher than that of fed batch fermentation.

Abstract:Stacked fermentation is an important part in the production of Moutai flavor liquor and has a great impact on the yield and quality of liquor. The study used PCR?鄄DGGE to reveal the change of microbial population in eight rounds of stacked fermentation during the production of Moutai flavor liquor. It was concluded that there was a certain rule in the change of microbial diversity：the bacterial species in stacked fermentation were more than fungal species during all rounds of stacked fermentation；for the first round，there were only a few microbial species；in the second round，the microbial diversity began to increase；when the fermentation came to the fourth round，the microbial diversity was most abundant；in the final round，the microbial diversity tended to decrease.