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Objective: This study aimed to optimize the pectin extraction yield from immature fruits of Guanxi pomelo by L. plantarum fermentation and analysis of the properties of pectin extracted by L.s plantarum fermentation. Methods: Taking the extraction yield of pectin as the index, orthogonal test was used to optimize the process conditions of fermentation of immature fruits of Guanxi pomelo by L. plantarum, and the content of galacturonic acid, degree of esterification, protein, water-holding capacity, oil-holding capacity, emulsifying activity and emulsion stability of pectin were determined. Results: The optimal conditions for fermentation of immature fruits of Guanxi pomelo by L. plantarum were as follows: fermentation temperature of 37 ℃, L. plantarum fermentation inoculum of 14%, liquid-solid ratio of 25∶1 (mL/g), and fermentation time of 12 h. Under the control of these conditions, the extraction yield of pectin was 11.60%, and the content of galacturonic acid; the degree of esterification, protein, water-holding capacity, oil-holding capacity, emulsifying activity and emulsion stabilities were about 26.13%, 68.58%, 0.53 g/g, 7.01 g/g, 14.33% and 33%, respectively. Conclusion: The extraction yield of pectin extracted by fermentation of L. plantarum was similar to that of the acid process, and the obtained pectin was highly esterified pectin with good application properties.

In this study, our purpose was to investigate the effect of mild salting on the flavor of large yellow croaker. The volatile flavor compounds of raw (unsalted) and low-salted large yellow croaker were determined by solid phase microextraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS) and evaluated by gas chromatography-olfactometry (GC-O) and odor activity values (OAV) analysis. The GC-MS analysis showed that the contents of hexanal, nonanal, heptanal, 1-octene-3-ol, anethole and hexanol in both samples were higher than those of other volatile compounds identified. GC-O and OAV analysis showed that the flavor of raw large yellow croaker was significantly affected by 1-octene-3-ol, octanal, nonanal, hexanal, heptanal, (E,Z)-2,6-nonadienal, trans-2-octenal and anethole (OAV > 1); the flavor of low-salted large yellow croaker was significantly affected by linalool, nonanal, hexanal, octanal, 1-octene-3-ol, anethole, (E,Z)-2,6-nonadienal and heptanal (OAV > 1). The changes in flavor after salting treatment was attributed to a significant increase in the OAV of linalool and anethole, and a significant decrease in the OAV of 1-octene-3-ol, hexanal, nonanal, trans-2-octenal, (E,Z)-2,6-nonadienal, heptanal and octanal. The changes of some flavor components might be related to reactions such as the oxidative degradation of unsaturated fatty acids, the biosynthesis of terpenoids, the isomerization of aromatic alcohols, the oxidation and reduction of aliphatic aldehyde and esterification.

In this study, the change of aroma components in instant Baiyaqilan tea powder during processing was investigated by sensory evaluation, gas chromatography-mass spectrometry (GC-MS) and odor activity value (OAV). The results showed that the over aroma profile and the types of aroma components in instant Baiyaqilan tea powder were similar at different stages of processing, while the aroma intensity and volatile components were significantly different. 3-Ethyl-2,5-dimethylpyrazine, hotrienol, methyl salicylate, safranal, geraniol, indole, β-damascenone, cis-jasmonone, geranyl acetone, trans-nerolidol and methyl jasmonate were found to make key contributions to aroma changes. The extraction process significantly increased the OAV of safranal, geraniol, indole, β-damascenone and cis-jasmonone. Disc separation, reverse osmosis and freeze drying significantly reduced the OAV of geraniol, indole, β-damascenone, cis-jasmonone, methyl jasmonate, trans-nerolidol, 3-ethyl-2,5-dimethylpyrazine and safranal. Moreover, ultrafiltration treatment removed tea polyphenol complexes, promoting the release of aroma volatile compounds combined with polyphenols and thus increasing the OAV of geraniol, indole, β-damascenone, cis-jasmonone and methyl jasmonate. This study clarified the aroma change during the processing of instant Baiyaqilan tea powder and showed that ultrafiltration treatment promoted the release of aromatic volatiles. This study can provide a theoretical basis for improving the processing of instant Baiyaqilan tea powder for improved aroma quality and the processing technology of instant tea.

In order to clarify the effect of the non-catalytic carbohydrate-binding module (CBM) and F5/8 type C domains on the enzymatic properties of AlgL7, an alginate lyase from Microbulbifer sp. ALW1, the full-length enzyme AlgL7 and two truncated enzymes: CD1 (catalytic domain) and CD2 (containing F5/8 type C domain and catalytic domain) were constructed and characterized. The results showed that the truncated enzyme CD2 exhibited higher specific activity, thermostability, Michaelis constant (Km), and maximum reaction velocity (Vmax) compared to the full-length AlgL7, indicating that the CBM domain played an important role in maintaining the substrate affinity of the enzyme, but reduced the catalytic activity, thermostability, and Vmax value the enzyme. Compared to the truncated enzyme CD1, CD2 exhibited higher specific activity, optimal reaction temperature, thermostability, Vmax, and Km, indicating that the F5/8 type C domain contributed to improve the enzymatic activity, optimum reaction temperature, thermostability, and Vmax, but reduced the substrate affinity of the enzyme. Using sodium alginate as the substrate, the specific activity of CD2 was 183.9 U/mg. The optimal reaction temperature and pH were 40 ℃ and 7.0, respectively. The Km and Vmax were 39.80 mg/mL and 2 000 U/mg, respectively. The major enzymatic hydrolysates were disaccharides and trisaccharides. This study promotes the understanding of the structure-activity relationship between the non-catalytic domains and the properties of alginate lyase, and lays a theoretical basis for using the non-catalytic domains to improve the catalytic properties of alginate lysate.

In this study, the total sugar, protein, 3,6-anhydro galactose and sulfate contents, apparent molecular mass and monosaccharide composition of porphyran isolated from Porphyra yezoensis were analyzed. The pro-angiogenic activity and underlying mechanism of porphyran were further investigated using human umbilical vein endothelial cells (HUVECs) as an in vitro angiogenesis model. The effect of porphyran on the cell viability of HUVECs was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell adhesion and migration capacity were evaluated using cell adhesion and wound healing assays. The number of lumens formed by HUVECs was analyzed using in vitro tube formation assay. The expression levels of E-cadherin and N-cadherin in HUVECs were analyzed by Western Blotting, and the pro-angiogenic mechanism of porphyran in HUVECs was explored using specific inhibitors of mitogen-activated protein kinases (MAPKs) and vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitors. The results showed that porphyran contained (77.48 ± 2.62)% total sugar, (3.24 ± 0.58)% protein, and (20.30 ± 1.06)% 3,6-anhydrogalactose as well as (20.78 ± 3.31)% sulfate groups. The apparent molecular mass of porphyran was 39.81 kDa. Porphyran was mainly composed of galactose, 3,6-anhydrogalactose and sulfate groups, suggesting it to be a sulfated galactan. Furthermore, porphyran treatment in the concentration range of 0–200 μg/mL had no significant toxicity no HUVECs, but instead promote cell proliferation, adhesion, migration, and vascular network formation. Further studies demonstrated that porphyran exerted its pro-angiogenic effect primarily by mediating the down-regulation of E-cadherin expression and the up-regulation of N-cadherin expression through the c-Jun N-terminal kinase (JNK) MAPK and VEGF receptor signaling pathways. In conclusion, porphyran has pro-angiogenic potential, which will provide a scientific basis for the development of porphyran as a novel pro-angiogenic factor and the precision nutrition-guided deep processing and high-value utilization of the red seaweed P. yezoensis.

Objective: This study aimed to improve the recrystallization yield and purity of flavonoid. Methods: Taking the crude flavonoids from pomelo peel extracted by ultrasonic-assisted ethanol extraction as raw materials, the process parameters of ethanol recrystallization and purification of flavonoids were optimized by response surface methodology. Results: The main factors affecting the recrystallization yield of flavonoids were ethanol concentration, crystallization time, pH value, and the interaction between ethanol concentration and pH value, among which, the ethanol concentration affacted most significantly. Conclusion: The optimal recrystallization conditions of flavonoids were as follows: ethanol volume fraction of 24%, liquid-solid ratio of 10∶1 (mL/g), pH 3.75, crystallization temperature of 4 ℃, and crystallization time of 24 h. The crystallization yield of flavonoids was 8.76%, and the main crystallization product was naringin with a purity of 83.38%.

Objective: In order to control the potassium ion content in Carrageenan, this project used alcohol inhibition method instead of potassium ion solution to extract Carrageenan. Methods: The volume fraction of ethanol in the processes of alkali treatment, alkali residual cleaning, and precipitation of carrageenan after filtration during the extraction were optimized for controlling K+ concentration. Results: The concentration of ethanol to inhibit the dissolution of Carrageenan was 60% in the process of alkali treatment and cleaning residual alkali, and the ratio of 60% ethanol solution to glue solution was 5∶1 in the process of Carrageenan precipitation. By using this process, the yield of Carrageenan was （28.76±1.38）%, and the Carrageenan of potassium ion was 0.63%, which was significantly lower than that of potassium ion extracted from traditional Carrageenan （16.26%）. In addition, the gel strength was significantly lower than that of Carrageenan extracted by traditional methods. And there was no significant difference in viscosity, hardness, elasticity, chewiness, and recovery between the two methods. Conclusion: K+ concentration and gel strength of Kappa-carrageenan extracted by ethanol inhibition were significantly lower than traditional technology.

The aim of this paper was to explore the process of β-glucosidase-assisted extraction of flavonoids from thinned fruits of Guanxi pummelo and the inhibitory effect of the extracted flavonoids on tyrosinase. In this paper, the extraction amount of total flavonoids was used as the index, and the β-glucosidase activity, enzymatic hydrolysis pH, temperature and time were optimized by single factor and response surface experiments, and the inhibitory effect of total flavonoids extract on tyrosinase was studied. The results showed that the optimal conditions for the extraction of flavonoids from thinned fruits of Guanxi pummelo were as follows: β-Glucosidase enzyme activity 0.0128 U/mL, enzymolysis pH4.4, temperature 35 t, time 4.8 h. Under these conditions, the extraction amount of total flavonoids was 34.0 mg/g, the half maximal inhibitory concentration (IC50) of the flavonoids extract on tyrosinase was 0.31 mg/mL. The results of this study showed that the enzymatic process could significantly improve the extraction amount of flavonoids from thinned fruits of Guanxi pummelo, and the flavonoids from thinned fruits of Guanxi pummelo had strong tyrosinase inhibition. The results of this study provided a reference for the extraction and application of flavonoids from thinned fruits of Guanxi pummelo, which was conducive to promoting the high-value utilization of Guanxi pummelo. [ABSTRACT FROM AUTHOR]

In order to clarify the differences in the aroma quality and its material basis between Tieguanyin tea and Baiyaqilan tea, the overall aroma profiles and the key aroma components of the two teas were analyzed by quantitative descriptive analysis (QDA), gas chromatography-mass spectrometry-olfactometry (GC-MS-O), and odor activity value (OAV). Except for the intensity of grassy note, the intensities of floral, sweet, caramel and roasted notes of Tieguanyin were significantly lower than those of Baiyaqilan tea (p<0.05). The total contents of the volatile compounds from the aqueous solutions of Tieguanyin and Baiyaqilan teas were 19 314.76 μg/L and 5 685.77 μg/L, respectively. GC-MS-O combined with OAV analysis showed that the key aroma-active components of Tieguanyin mainly included indole, cis-iasmine lactone, benzeneacetaldehyde, cis-jasmone and trans-nerolidol. The key aroma-active components of Baiyaqilan tea mainly included hotrienol, geraniol, cis-iasmine lactone, β-cyclocitral, trans-α-ionone, cis-jasmone, 3-ethyl-2,5-dimethyl-pyrazine, indole and safranal. The above results clarified the main aroma components accounting for the difference in aroma quality between Tieguanyin tea and Baiyaqilan tea, which provides a data reference for the precise control of tea quality. [ABSTRACT FROM AUTHOR]

5G XR and enhancement on media service are very important business scenarios in 5G-Advanced network. With the increasing user demands for emerging new media services, 5G network needs to make corresponding enhancements for media services such as XR. The main business scenarios of XR and augmented multimedia were mainly introduced, including immersive virtual reality, augmented reality, remote control technology based on mixed reality, virtual factory, remote unmanned aerial vehicle control, etc. For the typical business scenarios of XR, there were already some specifications and on-going studies in 3GPP. Based on these existing activities, 5G network need further enhancements including 5G QoS framework for XR service, coordination between network and application, synchronization of flows of multi-user and multi-stream, power saving of terminals and network etc., so that the 5G network could provide better support to 5G XR and enhanced media services leveraging the above enablers. [ABSTRACT FROM AUTHOR]

The agarase gene AL1 was amplified by PCR and cloned into pET-28a expression vector. The expression product was purified by affinity chromatography to study the enzymatic properties of the recombinant enzyme. The enzymatic hydrolysate was identified by TLC and LC-MS, and its reducing ability and scavenging ability of DPPH, ABTS+- and OH radicals were determined, and the antioxidant activity of the hydrolysate was analyzed. The molecular weight of the recombinant agarase from Agarivorans sp. AL1 was 105 ku. The agarase could specifically degrade agar as a β-agarase. The recombinant agarase showed the maximum activity at 50 °C and pH 7.00. The recombinant agarase was stable in a wide pH range from 5.00 to 11.00 below 50 C, indicating that the recombinant enzyme had good thermal stability and pH stability. The enzymatic hydrolysate product was identified as neoagarobiose by TLC and LC-MS. The enzymatic hydrolysates had the reducing power. The half-inhibition concentration IC50 of the enzymatic hydrolysate to OH, ABTS and DPPH free radicals are 1.28 mg/mL, 3.46 mg/mL and 9.87 mg/mL, respectively, indicating that the hydrolysate had good antioxidant activity. [ABSTRACT FROM AUTHOR]

Objective To investigate the relationship of hepatic immune cells (CD4+, CD8+, CD20+, and CD57+ T lymphocytes) with liver pathology and clinical relevance in chronic hepatitis B (CHB) patients with different HBeAg status. Methods A total of 70 CHB patients admitted to our hospital from January 2008 to December 2013 underwent liver biopsy, among whom 38 were HBeAg positive and 32 were HBeAg negative. Immunohistochemistry was used to examine the expression of CD4+, CD8+, CD20+, and CD57+ T lymphocytes in hepatic tissues, and the correlation between their expression and clinical relevance was analyzed in patients with different HBeAg status. Ranked data were analyzed by Kruskal - Walls H test. Comparison between groups was made by Nemenyi test. Correlation analysis was made by linear regression method. Results When inflammation reached to the level of G3 - G4 in patients with either positive or negative HBeAg, the expression of hepatic CD8+ and CD20+ cells in them was significantly higher than that in patients with inflammation level of G1 (all P < 0.05). When the levels of inflammation reached G4 in patients with positive HBeAg and G3 in those with negative HBeAg, the expression of hepatic CD4+ cells was significantly higher than that in patients with G1 inflammation (all P < 0.05). In patients with negative HBeAg, the CD4+, CD8+, CD20+, and CD57+ lymphocytes all showed a positive correlation with alanine aminotransferase (ALT) level (r = 0.353, 0.628, 0.693, and 0.540, respectively; all P < 0.05). In addition, CD20+ lymphocytes also showed a positive correlation with hepatitis B virus (HBV) DNA (r = 0.378, P < 0.05). However, in patients with positive HBeAg, only CD8+ and CD20+ lymphocytes showed a positive correlation with ALT level, and no correlation was found between all lymphocyte populations and HBV DNA. Conclusion The expression of CD4+, CD8+, and CD20+ lymphocytes was significantly correlated with the grade of inflammation in hepatic tissues in patients with different HBeAg status, whereas the correlations between hepatic immune cells and levels of ALT and HBV DNA vary. [ABSTRACT FROM AUTHOR]

Objective To summarize the complications of subclavian catheterization in severe hepatitis patients and to investigate clinical safety and treatment. Methods Five hundred and six cases of severe hepatitis, who underwent subclavian catheterization before non - bioartificial liver operation like double plasma molecular adsorption system, were enrolled. Intraoperative and postoperative adverse reactions were under close observation and recording. Results Of all patients, 492(97. 2% ) were punctured and catheterized successfully, and 38 (7. 5% ) developed complications, including local hematoma and bleeding at puncture sites ( 15 cases), catheter infection ( 13 cases), and catheterization into the subclavian artery (10 cases). Conclusion Subclavian catheterization has a high success rate, and is sufficient to meet the need of clinical rescue and treatment. Most complications would not interfere with treatment outcome after proper disposal. Subclavian catheterization can be safely applied to severe hepatitis patients with coagulation disturbance. [ABSTRACT FROM AUTHOR]

The hydrolysis of xylo-oligosaccharides catalyzed by β-xylosidase plays an important role in the degradation of lignocellulose. However, the enzyme is easily inhibited by its catalytic product xylose, which severely limits its application. Based on molecular docking, this paper studied the xylose affinity of Aspergillus niger β-xylosidase An -xyl, which was significantly differentially expressed in the fermentation medium of tea stalks, through cloning, expression and characterization. The synergistic degradation effect of this enzyme and cellulase on lignocellulose in tea stems was investigated. Molecular docking showed that the affinity of An -xyl to xylose was lower than that of Aspergillus oryzae β-xylosidase with poor xylose tolerance. The K i value of xylose inhibition constant of recombinant-expressed An -xyl was 433.2 mmol/L, higher than that of most β-xylosidases of the GH3 family. The K m and V max towards p NPX were 3.6 mmol/L and 10 000 μmol/(min·mL), respectively. The optimum temperature of An -xyl was 65 ℃, the optimum pH was 4.0, 61% of the An -xyl activity could be retained upon treatment at 65 ℃ for 300 min, and 80% of the An -xyl activity could be retained upon treatment at pH 2.0-8.0 for 24 h. The hydrolysis of tea stem by An -xyl and cellulase produced 19.3% and 38.6% higher reducing sugar content at 2 h and 4 h, respectively, than that of using cellulase alone. This study showed that the An -xyl mined from differential expression exhibited high xylose tolerance and higher catalytic activity and stability, and could hydrolyze tea stem lignocellulose synergistically, which enriched the resource of β-xylosidase with high xylose tolerance, thus may facilitate the advanced experimental research and its application.

Scopoletin is a coumarin compound with various biological activities including detumescence and analgesic, insecticidal, antibacterial and acaricidal effects. However, interference with scopolin and other components often leads to difficulties in purification of scopoletin with low extraction rates from plant resource. In this paper, heterologous expression of the gene encoding β-glucosidase An -bgl3 derived from Aspergillus niger were carried out. The expression product was purified and characterized with further structure-activity relationship between it and β-glucosidase analyzed. Subsequently, its ability for transforming scopolin from plant extract was studied. The results showed that the specific activity of the purified β-glucosidase An -bgl3 was 15.22 IU/mg, the apparent molecular weight was about 120 kDa. The optimum reaction temperature and pH were 55 ℃ and 4.0, respectively. Moreover, 10 mmol/L metal ions Fe 2+ and Mn 2+ increased the enzyme activity by 1.74-fold and 1.20-fold, respectively. A 10 mmol/L solution containing Tween-20, Tween-80 and Triton X-100 all inhibited the enzyme activity by 30%. The enzyme showed affinity towards scopolin and tolerated 10% methanol and 10% ethanol solution, respectively. The enzyme specifically hydrolyzed scopolin into scopoletin from the extract of Erycibe obtusifolia Benth with a 47.8% increase of scopoletin. This demonstrated that the β-glucosidase An -bgl3 from A . niger shows specificity on scopolin with good activities, thus providing an alternative method for increasing the extraction efficiency of scopoletin from plant material.

To examine the effects of management measures on carbon and nitrogen contents, as well as their distribution and structural characteristics of different soil fractions in Moso bamboo plantations, we compared three types of the bamboo forests (undisturbed, extensively managed, and intensively managed) and the control secondary broadleaved evergreen forest using the methods of physical fractionation, chemical and biological analysis and Fourier-transform infrared spectroscopy (FTIR). The results showed that soil total organic carbon (TOC) and total nitrogen (TN) content, as well as free particulate organic carbon and nitrogen, soluble organic carbon and nitrogen (DOC, DON), and mineral-associated organic carbon and nitrogen in the undisturbed and extensively managed Moso bamboo plantations were significantly increased compared with that in the control. The distribution ratio of free particulate organic carbon and nitrogen in the undisturbed Moso bamboo plantation significantly increased, with mineral-associated organic carbon being the largest reservoir of soil organic carbon (67.6%). Intensive management resulted in the decrease of soil organic carbon, total nitrogen storage, and the contents of each component, but significantly increased DOC/TOC, the ratio of microbial biomass nitrogen to TN as well as the ratio of microbial biomass carbon to TOC (microbial quotient). Management measures significantly affected the chemical structure of SOC. Compared with the control, the relative intensities of phenolic and alcoholic-OH, aliphatic methyl and methylene, aromatic C=C, and carbonyl C=O absorption were higher in the SOC of undisturbed and extensively managed Moso bamboo plantations, and soil hydrophobicity was significantly increased. Results from correlation analysis showed that soil hydrophobicity and the content of aliphatic and aromatic groups were negatively correlated with microbial quotient and positively correlated with TOC and TN content. In conclusion, the increased inputs of organic matter residues (such as litter and roots) could contribute to the relative accumulation of chemical resistance compounds with reduced human disturbance, which significantly enhanced chemical stability of soil organic carbon. Soil clay minerals played a key role in protecting soil organic carbon through the formation of mineral-organic compounds, which facilitate the stability of soil carbon storage and the long-term preservation of soil carbon.

Melanogenesis is a biosynthetic pathway to produce melanin pigment in melanocyte, involving a series of intricate enzymatic and chemical catalyzed reactions. Melanogenesis involves five signaling pathways that converge on microphthalmia-associated transcription factor. In addition, many cytokines, involved in the regulation of melanogenesis, play an important role in the development, proliferation, differentiation and migration of melanocytes. Polyoxometalate can be used as a potential inhibitor of melanin production. Hence, this paper reviews the signaling pathways of melanogenesis and their regulatory mechanism, to apply polyoxometalates in the melanin production pathway, and briefly introduces the regulatory factors of related pathways.

In order to study the effect of sediment of water extract of Guizhi decoction on the stability, clarity and peaks area, and characterize the chemical composition of the sediments, HPLC and MS methods were established. Through comparison of the common peak areas and the turbidity value of water extract and filtrate, the sediments could greatly change the common peak areas of the decoction (for more than 5 times of the study standard); at the same time, the turbidity value of the decoction could increase by （38.66±1.57）% in 48 h [particularly by （24.54±1.68）% in 6 h]. The test indicated that the sediments had an effect on the stability and clarity under the test conditions in Guizhi decoction. The study confirmed that the sediments were mainly derived from Cassia twig, Paeonia lactiflora and Glycyrrhiza uralensis. On the basis of the reference information, the accurate molecular weight and fragment ion information provided by LC-MS were analyzed, the molecular formula of sediments components A-F were determined, and the possible structural information of components B, C, D and F were deduced. It was suggested that the multi-index, multi-target and multi-angle analysis could ensure the quality of traditional Chinese medicine and the effect of clinical medication. The study also suggested the effect of the sediments on clinical application and the preparation of traditional Chinese medicine., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

In order to explore the spatial distribution and source of perfluorinated compounds (PFCs),eleven mixed urban soil samples were collected from 7 cities in Anhui Province in 2013.Fifteen individual PFCs were detected by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS),and principal components analysis was used to trace the different sources of PFCs in urban soil.The results showed that the total concentration of PFCs (Σ PFCs ) ranged from 1.15 to 5.98 ng·g -1 dry weight (dw),with an average concentration of 2.69 ng·g -1 .perfluorooctane sulfonate (PFOS) with a concentration range of n.d.-3.56 ng·g -1 and an average concentration of 0.96 ng·g -1 was the dominant PFC contaminant,followed by perfluorooctane acid (PFOA) with a concentration range of n.d.-2.89 ng·g -1 and an average concentration of 0.64 ng·g -1 .The highest Σ PFCs concentration in all selected mixed urban soil samples was from Chuzhou City with the value of 5.89 ng·g -1 ,followed by Jingxian County of Xuancheng City (4.04 ng·g -1 ).Interestingly,the PFOS concentration was as high as 3.56 ng·g -1 in Jingxian County,accounting for 88.1% of the total PFCs concentration,which might be influenced by paper industry in this area.Comparing to other soil samples in China,Σ PFCs concentration of urban soil from Anhui Province was at middle level.Over 60% of Σ PFCs in urban soil of Anhui province could be attributed to the four principal components,represented by PFOA,perfluorobutane sulfonate,perfluorododecanoic acid,perfluorobutane acid and PFOS.

Objective: This study was aimed to improve the thermal stability of carboxylesterase from Geobacillus sp. ZH1 by directed evolution., Methods: A library of carboxylesterase mutants was constructed by introducing random mutagenesis using error-prone PCR to screen mutant enzymes with improved thermostability. After induction, expression and purification, the mutant enzyme was characterized., Results: After screening, one mutant strain 65 was obtained with improved carboxylesterase thermal stability. Sequence analysis revealed two amino acid substitutions, including T113S and M160K. According to homologous modeling, T113S was located on the fifth β-sheet. Another mutant site M160K was located on a loop between the fifth and the sixth α-helix, being on the surface of the mutant enzyme. The mutated Lys160 formed an extra hydrogen bond with nearby Thr162. The half-life of mutant enzyme 65 and the parent enzyme at 90 degrees C was 3.1 h and 1.9 h, respectively. The mutant enzyme 65 had a better thermal stability than the parent enzyme., Conclusion: Directed evolution by error-prone PCR of Geobacillus sp. ZH1 carboxylesterase gene is effective to improve the thermal stability.

Objective: The aim of this study was to screen and identify carrageenase-producing strain from mangrove soil leaf and to characterize produced carrageenase., Methods: The culture medium with κ-carrageenan as sole carbon source was used to isolate the strain exhibiting carrageenase activity. The isolated strain was identified by morphology observation and 16S rDNA sequencing. κ-carrageenase produced by Pseudoalteromonas sp. ASY5 was purified and characterized by DNS method., Results: A bacterial strain ASY5 with high carrageenase activity was isolated from mangrove soil humus, and was identified as Pseudoalteromonas sp. The molecular mass of the purifiedenzyme was estimated to be 30 kDa. The optimal temperature and pH of the enzyme were 60°C and 7.5, respectively. The enzyme was stabileat 50°C, and more stable between pH 7.0 and 9.0. The enzyme could convert κ-carrageenan. The Km and Vmax values of the enzyme for κ-carrageenan was 2.28 mg /mL and 147.06 μmol/(min · mg), respectively. The enzyme was significantly stimulated by Na+, K+, Ca2+, Mg2+ and Al3+. The enzyme was inhibited strongly by Ag+, Zn2+, Cd2+ and SDS., Conclusion: κ-carrageenase produced by Pseudoalteromonas sp. ASY5 was stable at high temperature and alkaline pH, with potential application in carrageenan oligosaccharides production.

Objective: To identify and characterize a marine bacterial strain producing agarase., Methods: The agarase-producing bacterium was isolated from coastal sediments in Xiamen using agar as the sole carbon source. The strain was identified by the analyses of 16S rRNA gene sequence, phenotype and biochemical reactions. Agarase activity was determined by dinitrosalicylic acid method, and the category of agarase was assayed using chromogenic substrate. At last, the characteristics of agarase were determined., Results: The results of the 16S rRNA phylogenetic, phenotypic and biochemical analyses showed that: the agar-degrading bacterium NTa belonged to the genus Stenotrophomonas sp.. The strain could produce extracellular agarases, including alpha-agarase and beta-agarase. The optimum temperature and pH of strain NTa agarase were 40 degrees C and 7.0, respectively. The enzymatic activity was stable below 30 degrees C. It also showed stability over a pH range between 7.0 and. 0. Ca2+ could activate agarase activity, and Na+, K+ and Mg2+ had no significant influence. However, Ag', Ba2 , Fe2' , Mn2', Cu2', Zn2+ and Fe3' inhibited the enzyme activity. The enzymatic activity of stain NTa agarase was inhibited by EDTA. The agarase had good resistance to some inhibitors, detergents and denaturant., Conclusion: Stenotrophomonas sp. NTa is a new type of agarase-producing strain, which can produce both alpha-agarase and beta-agarase and has potential applications in the production of agaro-oligosaccharide.

Objective: A new naringinase-producing strain, JMUdb058 was identified and characterized., Methods: The strain was identified by morphological observation and 28S rDNA homogeneous analysis. Naringinase was identified by monitoring the hydrolysis of naringin to prunin and naringenin using a reversed phase High Performance Liquid Chromatography (HPLC). The regulation of naringinase expression was studied by measuring naringinase activity of 11 different carbon sources and 7 nitrogen sources in shaking cultivation. The naringinase-producing capacity was investigated in both solid-state fermentation and submerged fermentation., Results: The macro-morphology and micro-morphology of JMUdb058 corresponded to the characteristics of Aspergillus section Nigri Gams, and the 28S rDNA sequences showed homogeneity at 100% to Aspergillus aculeatus. Crude enzymes prepared by both submerged fermentation and solid-state fermentation could hydrolyze naringin to prunin and naringenin. In addition, the enzyme could remove naringin from citrus juice effectively. Carbon resources, including hesperidin, naringin, rutin and rhamnose, and organic nitrogen resources, i. e., tryptone, soybean meal, yeast extract and corn syrup were shown to express the naringinase. The strain had an outstanding ability to yield naringinase in the solid-state fermentation, which showed an alpha-L-rhamnosidase activity of 5903 U/gds by HPLC, and the naringinase of 1939U/gds by HPLC and 72232 U/gds by Davis method., Conclusion: It is the first time to report a stain of Aspergillus aculeatus can produce naringinase, carbon source containing rhamnose groups are able to induce the enzyme expression. The stain JMUdb058 is a new microorganism source for high yield of naringinase, in particularly by the solid-state fermentation.

Objective: To investigate the food water sources of adults in the four cities of China in summer., Methods: A total of 64 adults aged 18 - 60 yrs from four cities (Beijing, Shanghai, Chengdu and Guangzhou)were selected using convenient sampling method. The food samples were collected by using duplicate portion method and the water content of food samples were determined by using the national standard. The information on amounts and types of daily drinking soup was recorded by subjects using a quantitative measurement., Results: A total of 63 subjects had completed the investigation. The median of daily water from food of subjects was 1157 ml, while water from staple food was 480 ml, the median ratio of which accounting for 41.8% of water from food. Water from dishes was 427 ml, the median ratio of which accounting for 37.9% of water from food. Water from soups was 133 ml, the median ratio of which accounting for 13.8% of water from food. Water from snacks was 0 ml, the median ratio of which accounting for 6.4% of water from food. The medians of water from staple food (384, 388 and 435 ml, respectively) in Beijing, Shanghai and Guangzhou was significant lower than that of Chengdu subjects' (900 ml, χ(2) = 21.27, P = 0.000). But the median proportion of water from staple food of subjects in Beijing (47.7%) was significantly higher than that in Chengdu (43.2%), Shanghai (42.9%) and Guangzhou (33.9%) (χ(2) = 8.69, P = 0.034). The median of amount and proportion of water from soups of subjects in Guangzhou (267 ml, 24.4%) and Chengdu(278 ml, 15.7%) was significantly higher than that in Shanghai (133 ml, 9.0%) and Beijing (100 ml, 5.8%) (amount: χ(2) = 22.52, P = 0.000;proportion: χ(2) = 16.27, P = 0.001)., Conclusion: The staple food and dishes are the main sources of daily food water.

We evaluated an astaxanthin overproducing Phaffia rhodozyma JMU-MVP14, and developed astaxanthin high-yielding fermentation process. We analyzed several fermentation parameters, i.e., biomass, astaxanthin and total carotenoids content to compare the characteristics of P rhodozyma JMU-MVP14 and the original strain through flask fermentation experiments. We conducted batch and fed-batch fermentation experiments in 7 L fermentor to investigate the effects of pH controlling models and feeding medium compositions on the production of astaxanthin. We further evaluated the capability and practical value of P rhodozyma JMU-MVP14 by fed-batch cultivation in the 1 m3 fermentor. Flask fermentation experiments revealed that P. rhodozyma JMU-MVP14 produced high yield of astaxanthin and carotenoids with specific productivity of astaxanthin and specific productivity of total carotenoids of 6.01 mg/g and 10.38 mg/g. Results of batch culture experiments in the 7 L fermentor showed that controlling the pH by ammonia auto-feeding was better than discontinuously adjusting pH value at 6.0 with regard to the high productivities of biomasses and astaxanthin. This P. rhodozyma strain synthesized astaxanthin partially linked to the growth with the Ks and pmax of 0.20 h ' and 21.73 g/L, respectively. Results of batch-fed fermentations in 7 L fermentor indicated that the complex feeding medium consisted of 50% glucose, 0.5% yeast extract and 0.3% corn steep syrup had lower astaxanthin productivity than the simple feeding medium containing only 50% glucose, which produced biomass, volumetric productivity of astaxanthin, volumetric productivity of total carotenoids, specific productivity of astaxanthin and total carotenoids at 32.81 g/L, 155.99 mg/L, 4.94 mg/g, 399.99 mg/L and 12.19 mg/g, respectively. As fed-batch cultured in 1 m3 fermentor, P rhodozyma JMU-MVP14 yielded 85.11 g/L of biomass, 279.96 mg/L of volumetric productivity of astaxanthin, 618.01 mg/L of volumetric productivity of total carotenoids, 3.29 mg/g of specific productivity of astaxanthin and 7.26 mg/g of specific productivity of total carotenoids. Additionally, P rhodozyma JMU-MVP14 cell contained 21.54% of protein, 41.34% of carbohydrate and 34.31% of lipid. These comprehensive results suggest that P. rhodozyma JMU-MVPl14 has great practical prosperity related to its strong ability to produce astaxanthin and good value byproducts.

A comparative study of batch and repeated batch process was carried out for astaxanthin fermentation of Phaffia rhodozyma to develop a more economical method for astaxanthin industrial production. In shaking flask fermentation, the change of biomass and astaxanthin production was studied to compare the five-day cycle with four-day cycle of repeated batch culture of P. rhodozyma. Astaxanthin production increased at first and then decreased subsequently in seven cycles, yet the yield of astaxanthin in the next six cycles remains higher than that of the first cycle. Comparing the average production of astaxanthin in the seven cycles, four-day cycle performed even better than five-day cycle. Subsequently, a repeated fed-batch process was used in a 5-1 bioreactor. The experimental data showed that biomass and astaxanthin production of the second batch could reach the level of the first batch, no matter that the carbon source was glucose or hydrolysis sugar of starch. This result showed that this strain had good stability, and thus repeated batch and fed-batch process could be applied in astaxanthin fermentation for economical purpose.

Objective: We identified a new isolated naringinase-producing yeast strain named as Jmudeb008, and analyzed its naringinase-producing ability cultured with different composition and concentration of carbon sources., Methods: The strain was identified based on conventional phenotypic methods and sequences of the D1/D2 region of 26S rDNA and 5.8S-ITS. Media with different composition and concentration of carbon sources were used in shaking culture of Jmudeb008. The activity of naringinase was evaluated by analyzing the concentration of naringin, naringenin and glucose during 48 h culture., Results: The Jmudeb008's sequences of the D1/D2 region of 26S rDNA and 5.8S-ITS were 99% identical with Cryptococcus laurentii. Further glucose fermentation test, urease test, DBB (diazotization based blue) test and nitrate reduction test were coincided with results of DNA sequencing. Therefore, Jmudeb008 was identified as Cryptococcus laurentii. When Jmudeb008 was cultured in the medium with naringin as the only carbon source, it could synthesize naringinase. However, when glucose was available, the synthesis of naringinase was repressed., Conclusion: The new isolated naringinase-producing yeast strain JmudebO08 was identified as Cryptococcus laurentii. The glucose in medium repressed naringinase expression.

Ganoderma lucidum polysaccharides were extracted by boiling water from the fruiting bodies of red ganoderma lucidum, then protein was removed by Sevage reagent, with ethanol precipitation, run water dialysis, centrifugation and freeing-drying. Monosaccharides were acetylated and quantified by external standard, and the polysaccharides the amount of total carbohydrates was determined by phenol-sulfuric acid method. The monosaccharide constituents, structure and Mw distribution were analyzed by UV-Vis, IR, GC, GC-MS and HPSEC with ELSD. The results demonstrated that ganoderma lucidum polysaccharides were beige, the yield was about 2%, and the content > or = 43%. IR spectrometry showed that the structure of ganoderma lucidum polysaccharide was pyranoid glucan with beta-glycosidic bond. The quantitative result of external standards indicated that the monosaccharide constituents were mainly composed of glucose, at about 89% percent, and contained a small amount of D-arabinose, D-xylose, D-mannose and D-galactose. It was a homogeneous polysaccharide with the amorphous structure, attributed to biological macromolecules, its Mw distribution was at 80-2000 Kda, and a primary Mw at 2000 Kda.

Objective: To investigate the effect of Nifedipine on matrix metalloproteinase (MMP)-10 and MMP-13 expression in human periodontal ligament fibroblast (HPDLF) induced by mechanical strain in vitro., Methods: HPDLF was divided into four groups at random by mechanical strain of elongation 0%, 8%, 12% and 16%. Each group was divided into four subgroups again by the concentration of Nifedipine 0, 10, 30, 50 microm. The cells were imposed to state mechanical strain 12 h after incubated with Nifedipine 1 h. And then immunohistochemical staining was used to investigate the expressions of MMP-10 and MMP-13 in intracytoplasm., Results: In 0% group, there was no significant difference of MMP-10 and MMP-13 expression in all subgroups (P>0.05). The expressions of MMP-10 and MMP-13 were high in group 8%, 12% and 16% without Nifedipine, and increasing significantly with elongation (P<0.001). The expressions of MMP-10 and MMP-13 decreased with dose increasing (P<0.001) in HPDLF after imposed to Nifidepine., Conclusion: The expressions of MMP-10 and MMP-13 induced by mechanical strain were inhibited by Nifedipine, which suggested calcium ions channels participate in expressions of MMP-10 and MMP-13 induced by loading.

Objective: To compare the effect of three kinds of extraction model on high angle bimaxillary protrusion patients., Methods: A total of 30 patients with Class I malocclusion and bimaxillary protrusion, aged 14-25 years old, were selected and divided into three groups. Four first premolars were extracted in the first group. The two maxillary first premolars and two mandibular first molars were extracted in the second group. The two maxillary first premolars and two mandibular first molars were extracted in the third group, and two additional micro-implants used as orthodontic anchorage in maxilla. Three groups were all treated with MBT appliance. Cephalometric analysis were carried out before and after treatment, and the results were analyzed with statistics., Results: 1) About the hard tissues, compared with the first group, there were statistically significant differences of N-Me, SGo/NMe, ANS-Me, FH/MP, SN/MP, and ODI in the second and the third group after treatment (P<0.01). 2) About the soft tissues, the teeth and the alveolar bone, compared with the first group, there were statistically significant differences of Pg-Pos, Li-SnPos, Si-LiPos, LL-E, L1-NB, L1/NB, U1/L1, L7-MP in the second and the third group after treatment (P<0.01). 3) All patients received consummate orthodontic treatment and obtained fine occlusion. Facial profiles were improved significantly after orthodontic treatment., Conclusion: 1) After orthodontic treatment with mandibular first molars extraction, FH/MP, SN/MP, N-Me, ANS-Me, L1-NB and L1/NB decreased respectively, and soft tissue profiles were improved significantly. 2) Additional micro-implant used as orthodontic anchorage in maxilla significantly contributed to the maxillary incisor retraction and subsequent soft tissue change. 3) The first molars extraction and additional micro-implant used as orthodontic anchorage are efficient in improving the facial profiles for high angle bimaxillary protrusion patients.

Objective: To study the chemical constituents of Xanthoceras sorbifolia for explaining the active compounds., Methods: The constituents were isolated by silica gel column chromatography. Sephadex LH-20, MCI et al and the LC-MS-MS, 1H-NMR, 13C-NMR, CD spectroscopic analysis were employed for the structure identification., Results: 9 compounds were obtained and their structures were identified as (2R, 3R)-dihydromyricetin (I), myricetin (II), quercetin (III), (2R, 3S)-catechin (IV), gallocatechin (V), (2R, 3R)-3,3',5,5',7-pentahydroxyflavanone (VI), (2S) -3',4',5,5',7-pentahydroxyflavanone (VII), (-) epigallocatechin (VIII) , proanthocyanidin A2 (IX)., Conclusion: Compound I, IV, VI, VII are isolated from xanthoceras genus for the first time.

Phaffia rhodozyma is one of the organisms for production of astaxanthin, and the key process for extracting intracellular astaxanthin is cell disruption. In this work, cell disruption for extracting astaxanthin from Phaffia rhodozyma was studied with autoclave method at low acid concentration. The optimum disrupting conditions were: autoclave pressure 0.1 MPa, 121 degrees C; hydrochloric acid concentration 0.5 mol/L; liquid to material ratio (V/W) 30 mL/g dry cell weight and disruption time 2 min. Under the optimum conditions, medium scale experiment showed that astaxanthin and total carotenoids recovery from Phaffia rhodozyma were (84.8 +/- 3.2)% and (93.3 +/- 2)%, respectively. This new method can lead to no poisonous residues and get high extraction yield, which have good prospects to be put into industrial production.

A total of 87 yeast strains were isolated from 28 home-made koumiss samples, a traditional fermented mare milk product in Xinjiang of China. The isolates were identified by standard physiological and biochemical tests and analysis of the large-subunit (26S) rDNA gene D1/D2 domain sequences. They are proved to be Saccharomyces unisporus (48.3% of the isolates), Kluyveromyces marxianus (27.6%) and Pichia membranaefaciens (15.0%), Saccharomyces cerevisiae (9.2%). Among them, six isolates and a standard yeast strain were selected for analysis of D1/D2 domain sequences. They are indicated as S. unisporus, K. marxianus, S. cerevisiae, P. membranifaciens, P. fermentans, P. galeiformis and the standard yeast strain is indicated as K. lactis (100%). The results obtained demonstrate the value of using analysis of D1/D2 domain sequences methods, in conjunction with the traditional taxonomic methods based on phenotypic characteristics. This study forms an essential step towards the preservation and exploitation of the hidden oenological potential of the wealth of yeast biodiversity of the koumiss in Xinjiang Province. The result obtained shown that S. unisporus and K. marxianus were the predominant strains of koumiss in Xingjiang of China.

Survey on research and development of Fructus Gardeniae in the recent 10 years. Gardenia yellow has been used for food colorent, medicine, feedingstuff and cosmetic. Garnedia blue has been used for developing another pigment with red and yellow. Fructus Gardeniae has been used in digestive system for cholecyst constracting and gall-stone eliminating, for declining peroxide on SAP mouse and increasing immune ability, for protecting liver against cancel, anti-acetylcholinic restraining on stomach enginery, in cardiovascular system it has been used for centrally anti-hypertension, preventing atheroma and thrombus, also Fructus Gardeniae has been used for anti-inflammation, treating parenchyma injure etc. Geniposide used for increasing production in agriculture has wider perspect.

Objective: To study the effect of Lycium barbarum polysaccharides (LBP) on cleaning hydroxygen free radical., Methods: EPR., Result: When the concentrations of LBP were 0.25 mg/ml and 1.0 mg/ml, the cleaning rates of LBP to hydroxygen free radical were 18.64% and 87.29%., Conclusion: LBP in low concentration can obviously clean hydroxygen free radical, but its clearance ability in high concentration descends.

Objective: To study gentiopicroside's determination and comparison of various parts of herb by TLCS and make it impossible to uncover resource of Gentian in Xinjiang area., Method: Gentiopicroside's determination and comparison of various parts of herb in Gentiana Plants were carried out by TLCS., Result: The average recovery rate was 98.66% (RSD = 1.33%, n = 5). The Contents were stable. The results kept a high degree of comparable with HPLC ones., Conclusion: This method was good-steady, high-accurate, simple, convenient, sensitive, reproducible.