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Scientific spirit has a significance for scientific development, the scientific spirit is an important factor of scientific and technological progress. By analyzing the present situation of scientific spirit, this paper puts forward the cultivation strategy of scientific spirit. So as to explore knowledge, seek factual truth, innovate and progress, unite and cooperate, free compete and dedicate. First, the paper described the concept and significance of scientific spirit. And then, the present situation of scientific spirit is introduced through education, research and communication. Finally, scientific spirit is cultivated through four aspects: seeking knowledge spirit, dedication spirit, innovation spirit, and realistic spirit.

SUMMARYGravity controls directional growth of plants, and the classical starch-statolith hypothesis proposed more than a century ago postulates that amyloplast sedimentation in specialized cells initiates gravity sensing, but the molecular mechanism remains mysterious. Here, we report that gravistimulation by reorientation triggers the Mitogen-Activated Protein Kinase (MAPK) signaling-mediated phosphorylation of LAZY proteins, the key regulators of gravitropism accumulated more on the lower side of the plasma membrane in columella cells in regular growthArabidopsis. Phosphorylation of LAZY increases its interaction with several TOC proteins on the surface of amyloplasts, facilitating the translocation of LAZY proteins from the plasma membrane to the amyloplasts. Amyloplast sedimentation subsequently guides LAZY to relocate to the new lower side of the plasma membrane in columella cells, where LAZY induces asymmetrical auxin distribution and differential growth. Together, this study provides a molecular interpretation for the starch-statolith hypothesis: the organelle movement-triggered molecular polarity formation.

Nanoscale cerium oxide has excellent catalytic performance due to its unique surface properties and has very important applications in various fields. In this paper, the synthesis methods, catalytic mechanism and activity regulation of nanoscale cerium oxide in recent years are reviewed. Secondly, the application of cerium oxide in the detection of organic and inorganic molecules is summarized, and its latest progress and applications in antibacterial, antioxidant and anticancer are discussed. Finally, the future development prospect of nanoscale cerium oxide is summarized and prospected.

Lp was a generally recognized as safe microorganism. Lactobacillus plantarum 590 was obtained by inserting nisI gene into Lp genome to help it tolerate higher concentration nisin. As the unintended effects of the genetically modified microorganism (GMM) are the most important barriers to the progress of GMM, we have performed a useful exploration to establish a new in vivo evaluation model for GMM from the point of view of intestinal health. In this study, Sprague-Dawley rats were orally administered with Lp 590 and Lp for 4 weeks. Fecal samples were collected to determine the number of beneficial bacteria Bifidobacterium and harmful bacteria Clostridium perfringens. Denaturing gradient gel electrophoresis was used to detect the bacterial profiles of every group. Fecal enzyme activities and short-chain fatty acids as main metabolites were also examined. Real time PCR (RT-PCR) and immunohistochemistry were used to analyze two proteins (ZO-1 and occludin) and secretory immunoglobulin A to detect intestinal permeability and mucosal immunity, gut permeability and gut mucosal immunity were analyzed to see whether GM Lp 590 can induce changes of the gut health when compared with non-GM Lp group, andeventually we concluded that there is no significant difference between GM Lp 590-fed group and non-GM Lp-fed group. The conclusion of gut health test was comparable withthat from traditional subchronic test. Evaluation of intestinal health will be a new approach of assessing the safety of GMM.

Other than the targeted approach on compositional analysis, non-targeted approaches on genomics, proteomics and metabolomics are developing to search for unintended effects with respect to genetically modified (GM) food safety assessments. Antioxidant activity system was closely related with plant growth and reproduction as well as human health. This study was to investigate some other potential unintended effects from a range of primary and secondary metabolites by comparison of antioxidant activity system between six pairs of GMOs and their nontransgenic control. Antioxidant activity system was explored in total phenolics, unsaturated fatty acids and oxido-reductase activity analysis (including peroxidase (POD), polyphenol oxidase (PPO), catalase activity (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR)). The results from oxido-reductase activity analysis indicated significant differences (P < 0.05) between GMOs and their nontransgenic control, except for a few enzymatic activities of several GM crops. The data of total phenolics and unsaturated fatty acids also showed significant differences (P < 0.05) between GMOs and their nontransgenic control. However, no obvious differences occurred among all tested maize samples or canola samples.Key words: Unintended effects, antioxidant activity, genetically modified organisms, maize, canola.

Escherichia coli, Listeria monocytogenes, and Salmonella spp. are 3 kinds of the most important food-borne human pathogens. Traditional microbiological analysis is labor-intensive, time-consuming, and easily contaminated, thus producing false positive signals; it also involves much subjectivity judgments. Multiplex-PCR could be applied to detect multiple target organisms simultaneously to save time and labor, but there is always disproportionate amplification resulting from the disparity of different primers. To gain a rapid and sensitive method, a universal primer-multiplex PCR system (UP-M-PCR) was developed and applied for simultaneous detection of the 3 organisms. This method simplified traditional multiplex-PCR reaction system and overcame its amplification disparities among different primers; moreover, it got a high specificity and sensitivity (85, 155, and 104 copies/reaction for E. coli O157, L. monocytogenes, and Salmonella spp., respectively). Compared with the time-consuming and laborious microbiological analysis, UP-M-PCR had a lower risk of cross-contamination without inoculation and incubation. Test results for 36 food samples showed that UP-M-PCR method got a relative accuracy of 91.77% when compared with traditional microbiological analysis. It could serve as a rapid screening method for pathogen detection and could detect target genes even in dead pathogenic cells. In addition, it has the potential to be performed in an automation mode and might find broader application in simultaneous detection of other multiple pathogens.

A novel common primer multiplex PCR (CP-M-PCR) was applied to detect four kinds of meats (chicken, cattle, pig and horse) as raw materials. A common adapter was designed in the 5′-end of species-specific reverse primers which matched with the species-specific DNA sequences for each species and also used as the common primer (CP). CP-M-PCR primers were designed to uncover different length fragments of 239, 292, 412, and 451 bp from chicken, cattle, pig and horse meats, respectively. The bands of specific DNA fragments amplified by CP-M-PCR method still appeared until the concentration of species-specific primers diluted to 0.015 pmol and primer sensitivity was increased by 100 times compared with conventional multiplex PCR without CP. CP-M-PCR detection limit of the DNA samples was 0.1 ng (36.4 copies) for single kind of meat as well as four kinds of meats. CP-M-PCR method simplified the PCR reaction system and conquered the disparate amplified efficiency from different primers. The CP-M-PCR method could be widely applied in practical detection for simultaneous identification of other meat species and their products.

BACKGROUND: The Cry toxins are already a useful alternative or supplement to synthetic chemical pesticide application in commercial agriculture and forest management. RESULTS: The Cry1ab/ac gene from Bacillus thuringiensis was cloned from the genome of genetically modified rice by polymerase chain reaction (PCR). Owing to the large number of Escherichia coli low-usage codons in the Cry1ab/ac gene, the first 20 codons were optimised by PCR to improve the expression of the Cry1ab/ac gene in E. coli. The Cry1Ab/Ac protein was highly expressed in E. coli as inclusion bodies that could be dissolved in 8 mol L−1 urea and purified on a His Trap™ FF crude column under denaturing conditions. The purified Cry1Ab/Ac protein was dialysed in refolding buffers to obtain a soluble and biologically active protein. To achieve better biological activity, the His-tag was digested from the Cry1Ab/Ac protein with enterokinase, and the Cry1Ab/Ac protein was further purified by gel filtration on a fast performance liquid chromatography Superdex 75 HR 10/30 column using an AKTA purifier. The identity of the purified Cry1Ab/Ac protein sequence was confirmed by western blot and matrix-assisted laser desorption ionisation time-of-flight mass spectrometry. The final purified Cry1Ab/Ac protein was 99.2% pure and retained its biological activity, as determined in a growth inhibition assay of Chilo suppressalis. CONCLUSION: The purified Cry1Ab/Ac protein could be used to evaluate the food safety of transgenic plants containing the Cry1ab/ac gene and to produce antibodies for immune-based methods employed in the detection of genetically modified organisms containing the Cry1ab or Cry1ac gene. It might also serve as a new biological insecticide to reduce the use of broad-spectrum insecticides. Copyright © 2009 Society of Chemical Industry

A general and broad class selective competitive enzyme-linked immunosorbent assay (ELISA) for the detection of the alpha-cyano pyrethroids was developed. One class specific hapten, the 5-(3-benzylphenyl)-5-cyanopentanoic acid (CPBA-BE), was conjugated with BSA as an immunogen. Polyclonal antibodies, PY-antibodies, were generated. The assay with the most selectivity for the family alpha-cyano pyrethroids such as cyphenothrin was further optimized and tested for tolerance to cosolvent, pH, and ionic strength changes. The IC(50) values of the optimized immunoassay were 4.58 microg L(-1) for cyphenothrin, 5.62 microg L(-1) for fenpropathrin, 7.08 microg L(-1) for deltamethrin, 10.72 microg L(-1) for cypermethrin, 19.95 microg L(-1) for flucythrinate, and 28.18 microg L(-1) for esfenvalerate. The cross-reactivities of cyphenothrin, fenpropathrin, deltamethrin, cypermethrin, flucythrinate, and esfenvalerate were 100%, 81.49%, 64.68%, 42.72%, 22.96%, and 16.25%, respectively. The low detection limit (LDL) of this assay was 0.107 microg L(-1) for cyphenothrin. This method was used for the detection of the alpha-cyano pyrethroids in Tai lake water.

BACKGROUND: With the development of genetically modified organisms (GMOs), event-specific qualitative and quantitative polymerase chain reaction (PCR) detection methods have become the internationally agreed standard. RESULTS: The flanking regions of DAS-59122-7 maize were characterized by inverse PCR (I-PCR). In the qualitative PCR assay, a duplex PCR was established with the event-specific and taxon-specific primers, and the limit of detection (LOD) was 1 g kg−1 (approximates to 38 haploid genome copies). In the quantitative TaqMan® real-time PCR assay, a plasmidic reference material was constructed by recombinant PCR and standard curves were set up. By using the plasmidic reference material, we obtained standard curves with good linearity and relatively high efficiency. The results indicated the usability of the plasmid as standard material. CONCLUSION: From above results, we believe that the developed event-specific qualitative and quantitative PCR systems for DAS-59122-7 maize in this study are acceptable and suitable for DAS-59122-7 maize detection. Copyright © 2008 Society of Chemical Industry

BACKGROUND: Minced meat species adulteration is a severe problem. In this study a common single primer multiplex polymerase chain reaction (CSP-M-PCR) method was applied to the identification of five species (chicken, cattle, sheep, pig and horse) in minced meat products. CSP was designed as a common adapter at the 5′-end of species-specific reverse primers and employed in giving different length fragments from the respective meat species. RESULTS: Species-specific DNA fragments could be identified in a single PCR reaction by mixing CSP, Chicken-R, Cattle-R, Sheep-R, Pig-R and Horse-R primers in the ratio 1:0.01:0.01:0.01:0.01:0.10 (where ‘1’ represents 0.5 mmol L−1). The specific DNA fragments could be efficiently amplified by CSP-M-PCR with > 5 µmol L−1 species-specific primers, except for 50 µmol L−1 Horse-R. A detection limit of 0.5 g kg−1 was determined for both single species of minced meat and all species of five kinds of minced meat. CONCLUSION: The CSP-M-PCR method simplified the PCR reaction system and removed the inconsistent amplification efficiency from different primers. This highly sensitive, reproducible and rapid method could potentially be used as a screening or identifying assay to test for the presence of species or ingredients in minced meat and other meat products. Copyright © 2008 Society of Chemical Industry

Genetically modified (GM) papaya lines have been approved for commercialization and are widely cultivated in many countries. As a step towards the development of reliable qualitative and quantitative PCR methods for detecting GM papayas, one papaya (Fructus Caricae Carica papaya L.) species specific gene, papain, was selected and validated as suitable for using as an endogenous reference gene in transgenic papaya PCR detection. In this article, both qualitative and quantitative PCR assays for the papain gene were assayed with 11 different papaya varieties and identical amplification products were obtained with all of them. No amplified fragments could be detected when DNA samples from 18 kinds of other species were used as templates, which demonstrated that this system was specific for papaya. In real-time quantitative PCR analysis, the detection limit was as low as 10 pg of DNA. Southern blot analysis confirmed that the papain gene was two copies in the tested papaya varieties and no allelic variation was testified among these tested papaya varieties. In addition, the common used exogenous genes of the coat protein (CP) and the replicase (RP) were also assayed in qualitative and real-time quantitative PCR.

Bacillus thuringiensis insecticidal toxin (Bt) rice will be commercialized as a main food source. Traditional safety assessments on genetically modified products pay little attention on gastrointestinal (GI) health. More data about GI health of Bt rice must be provided to dispel public' doubts about the potential effects on human health. We constructed an improved safety assessment animal model using a basic subchronic toxicity experiment, measuring a range of parameters including microflora composition, intestinal permeability, epithelial structure, fecal enzymes, bacterial activity, and intestinal immunity. Significant differences were found between rice-fed groups and AIN93G-fed control groups in several parameters, whereas no differences were observed between genetically modified and non-genetically modified groups. No adverse effects were found on GI health resulting from genetically modified T2A-1 rice. In conclusion, this study may offer a systematic safety assessment model for GM material with respect to the effects on GI health.

Bacillus thuringiensis rice is facing commercialization as the main food source in the near future. The unintended effects of genetically modified (GM) organisms are the most important barriers to their promotion. We aimed to establish a new in vivo evaluation model for genetically modified foods by using metabonomics and bacterial profile approaches. T1c-19 rice flour or its transgenic parent MH63 was used at 70% wt/wt to produce diets that were fed to rats for ∼ 90 days. Urine metabolite changes were detected using (1)H NMR. Denaturing gradient gel electrophoresis and real-time polymerase chain reaction (RT-PCR) were used to detect the bacterial profiles between the two groups. The metabonomics was analyzed for metabolite changes in rat urine, when compared with the non-GM rice group, where rats were fed a GM rice diet. Several metabolites correlated with rat age and sex but not with GM rice diet. Significant biological differences were not identified between the GM rice diet and the non-GM rice diet. The bacteria related to rat urine metabolites were also discussed. The results from metabonomics and bacterial profile analyses were comparable with the results attained using the traditional method. Because metabonomics and bacterial profiling offer noninvasive, dynamic approaches for monitoring food safety, they provide a novel process for assessing the safety of GM foods.

The study on output allocative efficiency considering the emission trading is meaningful to allocate emission quota in order to promote production efficiency of industry. This chapter studies the output allocation problem with constraints to profit and pollution goals, and proposes three types of output allocative efficiency measures, including the comprehensive output allocative efficiency, the profit-oriented output allocative efficiency based on pollution constraint, and the pollution-oriented output allocative efficiency based on profit constraint, which aim to maximize the total profit and (or) minimize the total pollution. The proposed measures are used to evaluate the output allocative efficiencies of 32 paper mills along the Huai River in China, and different parameters are tested with sensitivity analysis to examine the changes of optimal output combination. This chapter helps the enterprise to optimize the decision of production and helps the government to formulate a reasonable plan of pollution control and treatment.

Lactobacillus plantarum (Lp) is a lactic acid bacterium that has many excellent traits that meet the needs of industrial production. Genetically modified (GM) Lp590 was obtained from Lp that was modified by the insertion of the gene nisI, which can confer resistance to nisin and play a role as a bio-preservative. Here, explorations were made to assess the safety of GM Lp590 and establish an in vitro evaluation model. The ability of Lp590 to tolerate both environmental stresses (such as temperatures ranging from 52 to 4 °C, or exposure to ethanol, oxygen, and osmotic stresses) and gastrointestinal transit was assessed. Lp590 showed a tolerance to 4 °C and ethanol (20%) within a period of 240 min that was similar to Lp. Notably, Lp590 can tolerate higher temperature (52 °C) and higher levels of H(2)O(2) (2%) and NaCl (4.0 M) than Lp. In contrast, Lp590 has the same gastrointestinal transit tolerance as Lp. In addition, Lp590 can adhere to Caco-2 cells, and it has no adverse effect on the cell membrane in vitro. These results indicate that GM Lp590 has many desirable biological characteristics and has good prospects for industrial applications. A useful and comprehensive exploration has been undertaken to establish a new in vitro evaluation model for genetically modified microorganisms (GMMs).

The Cry1C protein produced in Escherichia coli was used for in vitro evaluation and animal studies to support the safety assessment of GM food or feed products containing the Cry1C protein. The Cry1C protein does not have any sequence homology with known allergens or toxins. Although the Cry1C protein was heat stable it was rapidly degraded in vitro with simulated gastric or intestinal fluids. It did not cause adverse effects in mice as administered by gavage at a high level dosage of 5 g (Cry1C protein)/kg body weight. The mutagenicity of this protein was evaluated according to the national standards of People’s Republic of China (PR China) for a new food resource. In mutagenic tests, the Cry1C protein caused

More and more stacked GMOs have been developed for more improved functional properties and/or a stronger intended characteristic, such as antipest, improved product efficiency etc. Bt11 x GA21 is a new kind of stacked GM maize developed by Monsanto Company. Since there are no unique flanking sequences in stacked GMOs, up to now, no appropriate method has been reported to accurately detect them. In this passage, a novel universal primer multiplex PCR (UP-M-PCR) was developed and applied as a rapid screening method for the simultaneous detection of five target sequences (NOS, 35S, Bt11 event, GA21 event, and IVR) in maize Bt11 x GA21. This method overcame the disadvantages rooted deeply in conventional multiplex PCR such as complex manipulation, lower sensitivity, self-inhibition and amplification disparity resulting from different primers. What's more, it got a high specificity and had a detection limit of 0.1% (approximates to 38 haploid genome copies). Furthermore, real-time PCR combined with multivariate statistical analysis was used for accurate quantification of stacked GM maize Bt11 x GA21 in 100% GM maize mixture (Bt11 x GA21, Bt11 and GA21). Detection results showed that this method could accurately validate the content of Bt11, GA21 and Bt11 x GA21 in 100% GM mixture with a detection limit of 0.5% (approximates to 200 haploid genome copies) and a low relative standard deviation

Cry1ab/ac gene was fused by both the cry1ab gene (GenBank Accession No. X54939) and the cry1ac gene (GenBank Accession No. Y09787), which was widely used in genetically modified (GM) rice, cotton, maize and so on. In order to support the safety assessment of GM food or feed products containing Cry1Ab/Ac protein, sufficient quantities of Cry1Ab/Ac protein were produced in Escherichia coli for in vitro evaluation and animal studies. The Cry1Ab/Ac protein does not possess the characteristics associated with food toxins or allergens, i.e., it has no sequence homology with any known allergens or toxins, and no N-glycosylation sites, can be rapidly degraded in gastric and intestinal fluids, and is devoid of adverse effects in mice by gavage at a high dose level of 5g (Cry1Ab/Ac protein)/kg body weight. In conclusion, there is a reasonable certainty of no harm resulting from the inclusion of the Cry1Ab/Ac protein in human food or animal feed.

In this study, the formation of acrylamide upon treatment with microwave and conventional heating, boiling, or frying was investigated in both Asn/Fru and Asn/Glc model systems and in potato chips. Acrylamide levels were analyzed by HPLC method, which was confirmed by HPLC-MS/MS. Present results in model systems showed that pH value had a complex influence on the formation of acrylamide in the 2 systems during both microwaving (600 W) and boiling (120 +/- 1 degrees C). At pH < 8.0, acrylamide content increased with increasing the pH value, reaching the maximum at pH 8.0 whereas acrylamide content decreased with the increase of pH. Regardless of pH and heating methods, acrylamide content generally increased with increasing treatment time. Surprisingly, all present results showed that microwave heating not only induced acrylamide formation in the 2 model systems but also facilitated more acrylamide to be formed as compared to the boiling method at identical pH and treatment time. At pH 4.0, 8.0, and 10.0, the larger the microwave power, the more the acrylamide content. Consistent with the above observation, treatment of potato chips with microwave heating for 2.5 to 3.5 min in the range 550 to 750 W similarly resulted in acrylamide formation. The highest acrylamide content was formed by 750 W microwave treatment as 0.897 +/- 0.099 mg/kg, which was significantly higher than that produced by traditional frying (180 +/- 1 degrees C), 0.645 +/- 0.035 mg/kg (P < 0.05).

In this study, a novel universal primer-multiplex-PCR (UP-M-PCR) method adding a universal primer (UP) in the multiplex PCR reaction system was described. A universal adapter was designed in the 5'-end of each specific primer pairs which matched with the specific DNA sequences for each template and also used as the universal primer (UP). PCR products were analyzed on sequencing gel electrophoresis (SGE) which had the advantage of exhibiting extraordinary resolution. This method overcame the disadvantages rooted deeply in conventional multiplex PCR such as complex manipulation, lower sensitivity, self-inhibition and amplification disparity resulting from different primers, and it got a high specificity and had a low detection limit of 0.1 ng for single kind of crops when screening the presence of genetically modified (GM) crops in mixture samples. The novel developed multiplex PCR assay with sequencing gel electrophoresis analysis will be useful in many fields, such as verifying the GM status of a sample irrespective of the crop and GM trait and so on.

Rice is one of the most important staple foods in the world. The Cry2A gene was inserted into the rice genome to help the plant combat insects. As the unintended effects of the genetically modified (GM) organisms are the most important barriers to the promotion of GM organisms, we have carried out a useful exploration to establish a new in vivo evaluation model for genetically modified foods by metabonomics methods. In this study, the rats were fed for 90 days with the GM and NON-GM rice diets. The changes in metabolites of the urine were detected using (1)H-NMR. The metabonomics were analyzed to see whether the GM rice can induce the metabolite changes in the rats' urine when compared with the NON-GM rice group. The multivariate analysis and ANOVA were used to determine the differences and the significance of differences respectively, and eventually we concluded that these differences did not have a biological significance. The conclusion of the metabonomics was comparable with that from the traditional method. As a non-invasive and dynamic monitoring method, metabonomics will be a new way of assessing the food safety of GM foods.