Abstract:Aptamers are single-stranded oligonucleotides with the high affinity and high specificity binding of the target molecules. They can be obtained by systematic evolution of ligands by exponential enrichment(SELEX) in vitro screening. Aptamer is similar but superior to antibody,and it is becoming one specific issue of detection nowadays. This manuscript reviews the aptamer,screening methods,as well as applications in the analysis,food safety,clinical care and other areas in recent years.

Abstract:The prevalence of food allergy is continually increasing due to a large variety of food intake and tremendous lifestyle and living environmental changes in modern world. Food allergy incidences have gotten a sharp increase in recent years and food allergy has regarded as one of hot topics in food safety. Food processing may change the epitopes and the binding properties of allergenic protein,and subsequently causes the differences in activation of lymphocyte and cytokine release in the process of allergic reactions. However,due to the differences between food kinds,ingredients or processing techniques,without a general rules for food allergenicity changes caused by the way of processing. The IgE antibody level was regarded as the marker in allergy reaction,which was usually detected using enzyme-linked immunoabsorbent assay(ELISA) or immunoblotting measure. However,the methods above couldn’t tell whether allergens caused crosslinkingbetween FcεR1 and IgE,which leads to secondary inflammatory reaction. The overall assessment of food allergen not only includes the monitoring of IgE level but also includes the detection of effective cell activation and the release of cytokines. In this review,the effects of thermal processing on the allergenicity of food were summarized and the recent progress of in vitro cellular assay were highlighted for its application in assessment of food allergy.

Abstract:Ten fungi were screened with regard to their ability to convert major saponins Rb1,Rb2and Rc to Compound K(C-K) which has notable anti-tumor activity. Among these,strain sp. 3.26exhibited highest transfer ability. The strain sp. 3.26 was identified as Epicoccum sp. through ITS sequence analysis and morphology observation. A crude ginsenoside-hydrolyzing β-glucosidase(EI) was isolated from a culture filtrate of the strain sp. 3.26. The optimal pH and temperature of E-I were pH 5.0 and 40 ℃,respectively. E-I not only hydrolyze ginsenoside Rb1but also hydrolyze Rb2and Rc. However,E-I has higher activity to Rb1. This result indicated that the glycosidases secreted by strain sp. 3.26 has wide substrate specificity,and was more specific to glucosidic linkage,and the biotransformation pathways by this strain was:ginsenosides Rb1,Rb2,Rc→Rd→F2→C-K.

Abstract:In this manuscript,the effect of 9 kinds of vitamins on overproduction of L-tryptophan and cell growth were studied and the concentration of vitamins in culture medium was also optimized. The results showed that the cell growth and the synthesis of L-tryptophan were both promoted strongly with the addition of low concentration of inositol and folic acid. Their optimum concentrations were 0.000 2 mg/L,0.2 mg/L,respectively. Adding higher concentration of biotin can significantly promote cell growth and the synthesis of L-tryptophan,the optimum dosage was0.12 mg/L. The synthesis of L-tryptophan was inhibited severely by adding lower concentration of VB6,when the optimal added concentration was 0.8 mg/L,cell concentration and L-tryptophan production have been significantly improved by 11.8% and 27.2% compared with the control,respectively. Adding VB5may slightly improve the yield of the L-tryptophan,the optimal concentration was 0.4 mg /L. Although,adding VB1,VB2,VB3and VC,cell growth was improved strongly,the synthesis of L-tryptophan were inhibited by different degrees.

Abstract:In the manuscript,the effect of VB12,biotin,VB1,VB5,VB6on the growth of Schizochytriumsp.JN-168 and DHA production were studied with single factor experiment. The results showed that the additon of vitamins could efficient increase the DHA yield and the a optimum concentration were 0.1,0.005,0.005,0.3,0.05 mg/L,respectively. Amongt them,it was found that the highest DHA yield was achieved by VB12addition. Then follow by VB6,VB3,biotin and VB1. Futhermore,the simultaneously addition of these five kinds of vitamins with the optimum concentration could greatly improve the DHA yield. The final DHA yield was increased by 53.8%compared to the value of the control.

Abstract:To investigate the vasodilating effect of BNP in different buffer solutions,rabbit thoracic aorta was rapidly dissected out and the effect of BNP on the tension of aortic rings was measured in an organ bath system. The results showed that BNP in Citric acid/Na2HPO4 buffer caused a concentration-dependent relaxation. However,BNP in NaAc/HAC or K2HPO4/KH2PO4 buffer has vasodilating effect in dose-independent manner. The results indicate that BNP in Citric acid/Na2HPO4 buffer could keep its vasodilating effect in a dose-dependent manner,implying that they may be effective in BNP formulation.

Abstract:This paper proposed a method to detect three Dominant Spoilage Bacteria in pork based on olfaction visualization technique. At room temperature(20 ℃),cold(4 ℃) and freeze(-16 ℃)conditions,4 kinds of porphyrins were selected carefully to consist of visual sensors. The visual sensors was used to detect the pork sample which were infected three Dominant Spoilage Bacteria.The image processing techniques was used to collect images before and after the colorimetric sensor array interacted with pork svolatile flavors,then using principle components analysis(PCA) get digital signals which reflected the characteristics of pork sample flavors to discriminate above three Dominant Spoilage Bacteria. The detection results show that the recognition rates of the Pseudomonas koreensis group was achieved 98%,the Brochothrix thermosphacta group and Bacillus fusiformis group were achieved 100%. The research results show that olfaction visualization technology can discriminate three Dominant Spoilage Bacteria.

Abstract:S-adenosylmethionine(SAM) synthetase was expressed in E. coli,and then the purified SAM synthetase was immobilized on chitosan microspheres with glutaraldehyde crosslinking.Properties of the immobilized enzyme were identified. The results showed the optimal conditions for the immobilization of the enzyme were as follows:the mass fraction of chitosan was 2.5%;the volume fraction of glutaraldehyde was 0.8%;the amount of enzyme was 6 mg/mL gel;the immobilization time was 12 hours. Under these conditions,the activity yield of the immobilized enzyme was 76%. The immobilized enzyme showed a good stability compared with the free enzyme.After incubation at 55 ℃ for 5 h the immobilized enzyme maintained 53% of the original activity while the free enzyme lost all activity at 50 ℃ for 5 h. The immobilized enzyme also showed a good stability in alkaline solution. It still kept more than 80% of the original activity when incubated in the buffer of pH 7.5~9.0 at 4 ℃ for 10 h. The immobilized enzyme was employed to synthesize the SAM and it remained 64% activity after five times repeated operations. The substrate conversion rate was more than 95% in the presence of 30 mmol/L adenosine triphosphate(ATP)。

Abstract:In this manuscript,the water-soluble crude polysaccharides PEAP was extracted from Pleurotus Eryngii(PE) by alkali solution and fractionated by DEAE-52 cellulose and Sephadex G-150,obtaining a novel polysaccharide composition termed PEAP-1. Furthermore,the structural characteristics of PEAP-1 was analyzed by HPLC,GC,IR,Congo red test,AFM and SEM methods.The results of HPLC and GC analysis indicated that PEAP-1 was a homogeneous polysaccharide whose average molecular weight is 450 kDa and monoaccharide is composed of Glu and Gal at a molar ratio of 16.9∶0.37. Moreover,the peak near 832 cm-1and 919 cm-1suggested the presence of pyranose ring in PEAP-1 from the infrared spectroscopy. The Congo red test and atomic force microscope(AFM) images showed that PEAP-1 has no triple-helix structure but with multi-branched frame,and its single molecular presents random coil chain with a diameter of 0.13~1.2 nm.Meanwhile,the flake,rods and mesh morphology of PEAP-1 was detected using SEM.

Abstract:The objective of this manuscript is to study the effects of Pomegranate Peel Polyphenols,Punicalagine and ellagic acid on the expression of HMG-CoA reductase mRNA of human L-02hepatocyte. The model of steatotic L-02 hepatocyte was firstly established by cultured with 50%(V/V) fetal bovine serum for 48 hours,and the appropriate concentrations of PPPs were detected by MTT assay. Then the experiments were divided into three groups:normal group、model group and therapy group,different contents of PPPs is added to the therapy group. After 48 h cultured,the mRNA expression level of HMG-CoA reductase was detected by RT-PCR after 48 h cultured. It was found that the HMG-CoA reductase mRNA expression level was significantly inhibited by PPPs treatment groups,especially for the case of 100 μg/mL Punicalagin group. From the aboved results,the possible mechanisms of PPPs decreasing the intracellur cholestol are related to downregulation of HMG-CoA reductase mRNA’s expression,Punicalagin was the key component in PPPs on lipid-lowering.

Abstract:In this study,TAT-Oct4 target gene was inserted into pET28a expression vector to construct pET28a-TAT-Oct4 recombinant expression vector. TAT-Oct4 fusion protein was mainly expressed with insoluble inclusion bodies in E.coli. The purity of expression product was more than90% after purification. And the average refolding field is 8.8% using urea gradient dialysis.Immunocytochemistry analysis showed that TAT-Oct4 recombinant protein could penetrate nearly100% cells membrane and was mainly concentrated in nucleus. The method of generating active TAT-Oct4 recombinant protein was established in this article. It provided not only effective study materials for cell reprogramming but also practical method for other reprogramming factors design.

Abstract:Edgeworthia gardneri(Wall.) Meissn,a medicinal herb endemic to the Tibetan region,is used to treat Diabetes. The aim of this study is to identify the active ingredients of different extracts from the alabastrum of E. gardneri by the yeast and the rat intestinal α-glucosidase inhibitory assay. The alabastrum of E. gardneri was partitioned sequentially with n-hexane,petroleum ether,ethyl acetate,methanol,and water. Its α-glucosidase inhibitory activity was assayed by the method of 96-microplates. Acute toxicity study of active components for inhibition of α-glucosidase was carried out in Kunming mice of both sexes. A mouse model of diabetic disease induced by alloxan was used to evaluation of hypoglycemic activity. The results showed that yeastα-glucosidase inhibitory activity of petroleum ether extracts,ethyl acetate extracts,methanol extracts and water extracts were higer than that of positive control Acarbose,but only water extracts of E.gardneri(EMW,1 000 mg/kg) had the rat intestinal α-glucosidase inhibitory activity. EMW treatment was not acutely toxic to the mice. EMW at doses of 200 mg/kg and 300 mg/kg significantly decreased blood glucose in diabetic mice. The results indicate that EMW has a better yeast and rat intestinal α-glucosidase inhibitory activity in vitro and possesses antihyperglycaemic effect significantly in vivo.

Abstract:The target of this study is to develop a non-destructively detected method for the starch content of lotus root by near infrared spectroscopy technology. Three methods were applied to pretreat the spectrum data and then the NIR analysis models of the starch content of lotus root were established using PLS and SiPLS method. The results showed that the SiPLS model of the starch content of lotus root by multiple scattering correction,first derivative and smoothing preprocessing was optimum for the practical application. The correlation coefficient and RMSEC of calibration set were 0.960 0 and 0.741 6,and the correlation coefficient and RMSEP of prediction set were 0.923 8and 1.050 6. In conclusion,the near infrared spectroscopy technology was feasible to non-destructively measure the starch content of lotus root.

Abstract:The objective of this manuscript is to determine and analysis the stability and antioxidant activity and antibacterial activity of the pigment from the leaf of Photinia serrulata. The experiment results demonstrate that this kind of pigment is stable under acidic conditions and 60 ℃and poor light. The pigment has strong reduction and is able to effectively scavenge hydroxyl radical and superanion radical in vitro. Moreover,its scavenging effect has positive correlation with the pigment concentration. When the pigment is at the concentration of 0.32 mg/mL,the hydroxyl radical and superanion radical eradication rates are 89.66% and 74.71%. The antibacterial effect of pigment was different on three tested strains,in turn,Escherichia coli,Bacillus subtilis,Staphyloccus aureus Escherichia coli. The higher the concentration was,the stronger the antibacterial was. In conclusion,the pigment is relatively stable and the pigment has strong antioxidant activity and antibacterial activity.

Abstract:The aim of this manuscript was to check the antitumor activity of IOP3a and to elucidate the anticancer mechanism in vivo with cancer nude mice transplanted jurkat tumor as model.. it was found that tumor weight of high-dose and middle-dose had significant differences(p<0.05),when compared with the control group. Inhibition rate of tumor was 69.28% and 57.62%,respectively,which had an excellent dose-response relationship. IOP3a could increase the spleen index,white blood cell and lymphocyte with the increase of dosage. IOP3a promoted generation of TNF-α and L-1β from macrophage of nude mouse obviously. The histopathology of tumors indicated that the tumor cells from the different IOP3a-treated groups had clear necrosis areas in tumor tissues.The anti-tumor mechanism of IOP3a in vivo was that IOP3a could improve the expression of tumor gene Bax and inhibit the the expression of tumor gene Bcl-2 with immuno-histochemistry.

Abstract:The capacity of resisting ·OH,·O2-and H2O2of aqueous extractions from four organs(root,aerial stem,leaf and flower) of F. esculentum in vitro were estimated by means of nitro blue terra-zolium photochemica reduction,Fenton reaction and spectrophotometric assay. The results showed that the aqueous extractions had the capacity of resisting ·OH,·O2-and H2O2. The capacity of resisting ·OH was sorted as:aerial stem,flower >leaf,root. The capacity of resisting ·O2-was sorted as:flower >leaf,aerial stem >root. The capacity of resisting H2O2was sorted as:leaf,flower >root,aerial stem.

Abstract:In this manuscript,the separation and purification process of hesperidin from orange peel were developed,through investigating the effect of crude extract volume,pH and temperature on the variation of hesperidin partition and its recovery. Firstly two organic compounds with low molecular weight and three inorganic salts were selected to construct the aqueous two-phase system,whose performance was characterized by cloud point method. The chosen systems with good property in phase forming were applied to extract hesperidin from its crude ethanol extract,meanwhile the dependence of partition coefficient on the concentration of phase-forming substance and the type of system were also researched here. Therefore the best two-phase system was obtained,which is Acetone-K2HPO4and applied to extract hesperidin from the peels. The recovery of hesperidin could reach to 96.69% under the optimization condition. The extract was refined further with prep-HPLC and purer hesperidin product was received. Gradient elution strategy made the refining process more effective in prep-HPLC system. The purity of hesperidin samples obtained from aqueous two-phase extraction was about 71.36%. It increased to 96.09% ca. after pre-HPLC refining. The total recovery of hesperidin was 83.54%.

Abstract:The objective of this study was to investigate the protective effects of clove extracts on HL770 caused by the damage of H2O2 and its protective mechanism.For this,oxidative damage was induced by H2O2.The influence of clove extracts on H2O2-induced HL770 injury was assessed by measuring the superoxide dismutase(SOD),catalase(CAT),and glutathione peroxidase(GSH-Px)activities,the malondialdehyde(MDA)content and the ONOO-content.It was found that the addition of clove extracts(0.1,0.5,2,and 10 mg/L) into the HL770 cell suspensions prior to the exposure to 100 μmol/L of H2O2 resulted in increased protection of SOD,CAT and GSH-PX while reducing oxidation products of peroxynitrite MDA.From the above result,it is concluded that the clove extracts possess protective effects on HL770 cell injuries induced by H2O2,and this may be related to improve the activity of intracellular antioxidant enzymes of HL7702,reduce the content of oxidation products.