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Bioactive peptides play important roles in promoting human health, such as lowering blood pressure, blood sugar and blood lipid, anti-obesity, and anti-cancer. Thus, exploring functional bioactive peptides and developing efficient production technologies are of crucial importance. Herein, we review the development of function discovery and production technology for natural bioactive peptides. Presently, the top-down and bottom-up approaches are mainly used for the function discovery and production of natural active peptides. The top-down approach includes the direct extraction and identification for functional discovery, and the direct extraction, enzymatic hydrolysis and microbial fermentation for production. The bottom-up approach includes the polypeptide modification and database mining for functional discovery, and the chemical synthesis, enzyme synthesis, recombinant expression and cell-free synthesis for production. The top-down approach is usually associated with complicated process, lower efficiency, higher cost, harder quality control, and uncertain functionality, while the bottom-up approach is more suitable for the development of peptide drugs but difficult to be used for functional foods. With the technology development of sequencing and mass spectrometry, it is easier to obtain the proteomic information of various organisms at the molecular level. Based on the proteomic information, the top-down and bottom-up approaches can be combined to overcome the disadvantages of using these two approaches alone, thus providing a new strategy for the rapid development and production of natural active peptides.

Since microdroplets are able to be generated rapidly in large amount and each droplet can be well controlled as an independent micro-cultivator, droplet microfluidic technology can be potentially used in the culture of microorganisms, and provide the microbial culture with high throughput manner. But its application mostly stays in the laboratory-level building and using for scientific research, and the wide use of droplet microfluidics in microbial technology has been limited by the key problems that the operation for microdroplets needs high technical requirements with wide affecting factors and the difficulties in integration of automatic microdroplet instrumentation. In this study, by realizing and integrating the complicated operations of droplet generation, cultivation, detection, splitting, fusion and sorting, we design a miniaturized, fully automated and high-throughput microbial microdroplet culture system (MMC). The MMC can be widely used in microbial growth curve test, laboratory adaptive evolution, single factor and multi-level analysis of microbial culture, metabolite detection and so on, and provide a powerful instrument platform for customized microbial evolution and screening aiming at efficient strain engineering.

With pot experiment, two soybean (Glycine max) varieties, Jindou 21 (drought-tole-rant) and Xudou 22 (drought-sensitive), were used to examine the effects of α-naphthaleneacetic acid (NAA) on carbon metabolism of soybean under drought stress at flowering stage. The results showed that under drought stress, compared to Xudou 22, Jindou 21 had smaller decrease in net photosynthetic rate (P n ), smaller increase in photorespiration rate (P r ) and soluble sugar content of leaves, while a greater increase in the activities of sucrose phosphate synthase (SPS) and sucrose synthetase (SS) (synthesis) of leaves and sucrose content of roots. NAA treatment increased P n and decreased P r under drought stress, and thus obviously alleviated the growth inhibition of drought stress on plants. NAA treatment reduced the activities of starch-degrading enzymes, acid invertase (AI) and SS (cleavage), thereby inhibited the accumulation of soluble sugar induced by drought stress. In addition, NAA treatment increased SPS and SS (synthesis) activities of leaves, sucrose content of roots and shoot-root ratio, indicating that NAA treatment improved the transportation of sucrose from leaf blade to root under drought stress. In conclusion, exogenous NAA could enhance drought tolerance in soybean by regulating carbon metabolism.

Two different drought tolerance soybean ( Glycine max) varieties (Nannong 99-6 and Kefeng 1) were used to study the effects of α-naphthaleneacetic acid (NAA) on the antioxidation system under long-term drought stress after flowering with pot experiment, which lasted for 110 days at Pailou Experiment Station, Nanjing Agricultural University, in 2012. The results showed that long-term stress decreased the shoot dry mass significantly, however, increased the level of reactive oxygen species (ROS) and malondialdehyde (MDA) content. It also obviously increased the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) , ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), glutathione reductase (GR) and glutathione peroxidase (GPX). The contents of ascorbic acid (AsA) and glutathione (GSH), and the ratios of AsA/DHA (dehydroascorbic acid) and GSH/GSSG (L-glutathione oxidized) were obviously enhanced. Kefeng 1 showed a higher antioxidation ability than Nannong 99-6, and could consequently maintain lower ROS and MDA levels. NAA distinctly enhanced the activities of APX, POD, CAT, MDHAR, GPX, and ratios of AsA/DHA and GSH/GSSG, while decreased the levels of ROS and MDA. The AsA content and dehydroascorbate reductase (DHAR) activity were significantly increased in Kefeng 1.

The carrier is the key influencers in moving bed biofilm reactor( MBBR), in this paper, a pilot scale apparatus was set up for treating municipal wastewater using modified cubic polyurethane carriers. For MBBR, the capacity of 3-3.5 t x d(-1), hydraulic residence time of 7-8 h, under the condition of continuous feed water (COD:140-280 mg x L(-1), NH4+ -N:30-50 mg x L(-1), TN: 45-65 mg x L(-1), TP:2.5-4.0 mg x L(-1)), the speed of biofilm formation and removal effects of COD, nitrogen and phosphorus were studied. After 140 days, the results showed that the formation of biofilm on the carrier was very quickly under 24-28 degrees C, and obtained stable treatment effect about 6 days. The COD, NH4+ -N, TN, TP average removal rates were 70%, 97%, 70%, 39%, respectively. As the temperature gradually decreased to about 12 degrees C, a high NH4+ -N removal rate (97%) could still be maintained, which indicating that the modified carrier can be achieved a high nitrification rate at low temperature.

This study was aimed to explore the expression of microRNA-21 (miR-21) in multiple myeloma (MM), and its correlation with plasma β2-microglobulin (β2-MG) and staging of MM by Durie-Salmon (D-S) classification. The expression level of miR-21 in bone marrow mono-nuclear cells (BMMNC) of 43 patients with MM and 20 healthy individuals was examined by real-time polymerase chain reaction (real-time PCR), and the correlations among the expression level of miR-21 and related clinical pathologic features, plasma β2-MG and staging of MM by D-S classification were analyzed. The results showed that the expression of miR-21 in BMMNC of MM patients was obviously higher than that in normal controls (P < 0.05). The expression of miR-21 in BMMNC of relapsed/refractory MM patients was obviously higher than that in newly diagnosed MM patients. The expression of miR-21 in MM patients decreased after chemical therapy, especially in effective group (P < 0.05), there was no significant change of miR-21 expression level in ineffective/progressive group before and after chemical therapy (P > 0.05). The expression of miR-21 was related with staging of MM and plasma β2-MG level. It is concluded that the expression levels of miR-21 in BMMNC of MM patients are significantly higher than in normal bone marrow, these data indicated that miR-21 may play an important role in the development of MM. Super expression of miR-21 is positively correlated with level of plasma β2-MG and staging of MM by D-S classification.

This study was aimed to explore the expression of B cell-activating factor of TNF family (BAFF) and B cell lymphoma/leukemia-2 (BCL-2) in bone marrow mononuclear cells (BMMNC) of multiple myeloma (MM) and the significance of BAFF and BCL-2 for occurrence, development and prognosis of MM. The bone marrow of 40 cases of MM and 10 healthy persons was collected, the mononuclear cells (MNC) were isolated, the expression of BAFF and BCL-2 mRNA in BMMNC was detected by real-time PCR; the plasma was simultaneously collected and the β2-MG level was determined; the clinical staging of MM patients was performed according to Durie-Salmon (D-S) staging criterion. The results indicated that the expression level of BAFF and BCL-2 mRNA in MM patients increased, as compared with normal controls, the difference was statistical significant (p < 0.05); the expression level of BAFF and BCL-2 mRNA in plateau stage after treatment obviously decreased. The expression level of BAFF and BCL-2 mRNA in relapsed/refractory MM patients was significantly higher than that in normal controls and patients reached plateau stage (p < 0.05), there was no statistically significant difference between newly diagnosed and relapsed/refractory MM patients (p > 0.05). The expression of BAFF and BCL-2 mRNA related with D-S staging and β2-MG level. It is concluded that the expression levels of BAFF and BCL-2 mRNA increase, moreover the expression levels of BAFF and BCL-2 mRNA in newly diagnosed and relapsed/refractory MM patients are higher than those in patients reached plateau stage, which suggest the BAFF and BCL-2 may be involved in occurrence and development of MM; the relation of expression level of BAFF and BCL-2 mRNA to MM load is positive, which indicates the expression level of BAFF and BCL-2 mRNA may be a new indicator for evaluating the prognosis of MM patients.

Objective: To examine the expression of molar root patterning gene 1 (Mrp1) and predict the Mrp1 structure by bioinformatics analysis., Methods: A pair of Mrp1-specific PCR primers were designed, and RT-PCR method was used to study the mRNA's expression pattern in rat molar root and other organs. Gene positioning and other protein sequence prediction were carried out by chromosome analysis and other bioinformatics analysis., Results: Mrp1 was expressed not only in the molar but also in the developing pancreas, liver, lung and kidney tissues. Mrp1 was located in the 18q12.3 chromosome of the rats and the Mrp1 amino acids sequence had about 37% homology with a known protein Uroplakin IIIb (p35) which was an urothelial differentiation membrane molecular marker. A trans-membrane structure, 5 PKC phosphorylation sites and 4 CKII phosphorylation sites in Mrp1 were found., Conclusions: Mrp1 has a broad expression in different developing organs, and it may have a important function in the rat tooth root development.

From an agricultural sample taken in Chongqing, a stable methane-oxidizing mixed microbial consortium was established by enrichment culture with methane as a sole source of carbon and energy. The mixed consortium showed high capability of phenol degradation and 1,2-epoxypropane production from propene. More than 99% of phenol at an initial concentration of 600mg/L could be degraded by the mixed microbial consortium after 11 h of cultivation. The productivity of 1, 2-epoxypropane could be increased with the decrease of phosphate concentration. The concentration of 1, 2-epoxypropane produced could reach to 5.0mmol/L. The bacterial structure of the methane-oxidizing mixed microbial consortium was analyzed by pure culture isolation combining with 16S rRNA and PCR of the related MMO functional genes. The results showed that the methane-oxidizing mixed microbial consortium was composed of a type 1U methanotroph identified as Methylosinus trichosporium and at least 4 kinds of heterotrophs ( Comamonas testosteroni, Cupriavidus metallidurans, Acinetobacter junii and Stenotrophomonas maltophilia ). M. trichosporium Y9, isolated from the mixed consortium, harbored both sMMO and pMMO genes.

Green fluorescent protein (GFP) can be utilized in analysis of the characteristics and distribution of a targeted strain in microbial communities. This study is the first step to establish a dynamic yeast monitoring technique in a wastewater treatment system using yeast by constructing a fluorescent yeast containing gfp gene. The gfp gene was inserted into pACT1-URA3, a powerful plasmid for introducing a foreign gene into Candida boidinii, and then transformed into E. coli JM109. The gfp gene was expressed, though not very highly. The results of the electrophoresis and polymerase chain reaction suggested that the newly constructed plasmid containing gfp gene might not exist in free form in the cells, but in some special way such as interaction with the chromosome.