196 research outputs found

    An endophytic Taxol-producing fungus BT2 isolated from Taxus chinensis var. mairei

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    BT2, a newly isolated endophytic fungus from Taxus chinensis var. mairei, was observed to produce Taxol. Besides Taxol, a potent anticancer drug, BT2 could also yield taxane baccatin III, which was an important intermediate for Taxol and semi-synthesis of Taxol in industry. The isolation of such a fungusmay provide a promising alterative approach to produce Taxol, and BT2 can serve as a potential material for fungus engineering to improve Taxol productio

    Developmental Transcriptomic Features of the Carcinogenic Liver Fluke, Clonorchis sinensis

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    Clonorchis sinensis is the causative agent of the life-threatening disease endemic to China, Korea, and Vietnam. It is estimated that about 15 million people are infected with this fluke. C. sinensis provokes inflammation, epithelial hyperplasia, and periductal fibrosis in bile ducts, and may cause cholangiocarcinoma in chronically infected individuals. Accumulation of a large amount of biological information about the adult stage of this liver fluke in recent years has advanced our understanding of the pathological interplay between this parasite and its hosts. However, no developmental gene expression profiles of C. sinensis have been published. In this study, we generated gene expression profiles of three developmental stages of C. sinensis by analyzing expressed sequence tags (ESTs). Complementary DNA libraries were constructed from the adult, metacercaria, and egg developmental stages of C. sinensis. A total of 52,745 ESTs were generated and assembled into 12,830 C. sinensis assembled EST sequences, and then these assemblies were further categorized into groups according to biological functions and developmental stages. Most of the genes that were differentially expressed in the different stages were consistent with the biological and physical features of the particular developmental stage; high energy metabolism, motility and reproduction genes were differentially expressed in adults, minimal metabolism and final host adaptation genes were differentially expressed in metacercariae, and embryonic genes were differentially expressed in eggs. The higher expression of glucose transporters, proteases, and antioxidant enzymes in the adults accounts for active uptake of nutrients and defense against host immune attacks. The types of ion channels present in C. sinensis are consistent with its parasitic nature and phylogenetic placement in the tree of life. We anticipate that the transcriptomic information on essential regulators of development, bile chemotaxis, and physico-metabolic pathways in C. sinensis that presented in this study will guide further studies to identify novel drug targets and diagnostic antigens

    Ultrasound-assisted extraction of natural products

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    Ultrasound-assisted extraction (USAE) is an interesting process to obtain high valuable compounds and could contribute to the increase in the value of some food by-products when used as sources of natural compounds. The main benefits will be a more effective extraction, thus saving energy, and also the use of moderate temperatures, which is beneficial for heat-sensitive compounds. For a successful application of the USAE, it is necessary to consider the influence of several process variables, the main ones being the applied ultrasonic power, the frequency, the extraction temperature, the reactor characteristics, and the solvent-sample interaction. The highest extraction rate is usually achieved in the first few minutes, which is the most profitable period. To optimize the process, rate equations and unambiguous process characterization are needed, aspects that have often been lacking. © 2011 Springer Science+Business Media, LLC.The authors thank the Generalitat Valenciana for their financial support in project PROMETEO/2010/062 and the Caja de Ahorros del Mediterraneo for M.D. Esclapez's pre-doctoral grant.Esclapez Vicente, MD.; García Pérez, JV.; Mulet Pons, A.; Cárcel Carrión, JA.; Esclapez, MD. (2011). Ultrasound-assisted extraction of natural products. Food Engineering Reviews. 3(2):108-120. https://doi.org/10.1007/s12393-011-9036-6S10812032Abad Romero B, Bou-Maroun E, Reparet JM, Blanquet J, Cayot N (2010) Impact of lipid extraction on the dearomatisation of an Eisenia foetida protein powder. Food Chem 119:459–466Adewuyi YG (2001) Sonochemistry: environmental science and engineering applications. Ind Eng Chem Res 40:4681–4715Atchley AA, Crum LA (1988) Acoustic cavitation and bubble dynamics. In: Suslick KS (ed) Ultrasound, its chemical, physical, and biological effects. VHS Publishers, Weinheim, pp 1–64Arnold G, Leiteritz L, Zahn S, Rohm H (2009) Ultrasonic cutting of cheese: composition affects cutting work reduction and energy demand. Int Dairy J 19:314–320Barbero GF, Liazid A, Palma M, Barroso CG (2008) Ultrasound-assisted extraction of capsaicinoids from peppers. Talanta 75:1332–1337Benedito J, Carcel JA, Sanjuan N, Mulet A (2000) Use of ultrasound to assess Cheddar cheese characteristics. Ultrasonics 38:727–730Benedito J, Carcel JA, Rossello C, Mulet A (2001) Composition assessment of raw meat mixtures using ultrasonics. Meat Sci 57:365–370Bhaskaracharya RK, Kentish S, Ashokkumar M (2009) Selected applications of ultrasonics in food processing. Food Eng Rev 1:31–49Boonkird S, Phisalaphong C, Phisalaphong M (2008) Ultrasound-assisted extraction of capsaicinoids from Capsicum frutescens on a lab- and pilot-plant scale. Ultrason Sonochem 15:1075–1079Cárcel JA, Benedito J, Bon J, Mulet A (2007) High intensity ultrasound effects on meat brining. Meat Sci 76:611–619Cárcel JA, Benedito J, Rosselló C, Mulet A (2007) Influence of ultrasound intensity on mass transfer in apple immersed in a sucrose solution. J Food Eng 78:472–479Cavitus (2009) Grape colour and flavour extraction (Pat. Pend.) for red must extraction http://www.cavitus.com . Crafers. Accessed 10 Jan 2011Chea Chua S, Ping Tan C, Mirhosseini H, Ming Lai O, Long K, Sham Baharin B (2009) Optimization of ultrasound extraction condition of phospholipids from palm-pressed fiber. J Food Eng 92:403–409Chena R, Menga F, Zhang S, Liu Z (2009) Effects of ultrahigh pressure extraction conditions on yields and antioxidant activity of ginsenoside from ginseng. Sep Purif Technol 66:340–346Chivate MM, Pandit AB (1995) Quantification of cavitation intensity in fluid bulk. Ultrason Sonochem 2:19–25Da Porto C, Decorti D (2009) Ultrasound-assisted extraction coupled with under vacuum distillation of flavour compounds from spearmint (carvone-rich) plants: comparison with conventional hydrodistillation. Ultrason Sonochem 16:795–799Da Porto C, Decorti D, Kikic I (2009) Flavour compounds of Lavandula angustifolia L. to use in food manufacturing: Comparison of three different extraction methods. Food Chem 112:1072–1078Domínguez H, Núñez MJ, Lema JM (1994) Enzymatic pretreatment to enhance oil extraction from fruits and oilseeds: a review. Food Chem 49:271–286Dong J, Liu Y, Liang Z, Wanga W (2010) Investigation on ultrasound-assisted extraction of salvianolic acid B from Salvia miltiorrhiza root. Ultrason Sonochem 17:61–65Entezari MH, Kruus P (1994) Effect of frequency on sonochemical reactions. I: oxidation of iodide. Ultrason Sonochem 1:75–79Esclapez MD, Sáez V, Milán-Yáñez D, Tudela I, Louisnard O, González-García J (2010) Sonoelectrochemical treatment of water polluted with trichloroacetic acid: from sonovoltammetry to pre-pilot plant scale. Ultrason Sonochem 17:1010–1020Ferraro V, Cruz IB, Ferreira R, Malcata JFX, Pintado ME, Castro PML (2010) Valorisation of natural extracts from marine source focused on marine by-products: review. Food Res Int 43:2221–2233Fischer CH, Hart EJ, Henglein AJ (1986) Hydrogen/deuterium isotope exchange in the hydrogen deuteride-water system under the influence of ultrasound. Phys Chem 90:3059–3060Garcia-Noguera J, Weller CL, Oliveira FIP, Rodrigues S, Fernandes FAN (2010) Dual-stage sugar substitution in strawberries with a Stevia-based sweetener. Innovative Food Sci Emerg Technol 11:225–230García-Pérez JV, Cárcel JA, de la Fuente-Blanco S, Riera-Franco de Sarabia E (2006) Ultrasonic drying of foodstuff in a fluidized bed: parametric study. Ultrasonics 44:539–543García-Pérez JV, García-Alvarado MA, Carcel JA, Mulet A (2010) Extraction kinetics modeling of antioxidants from grape stalk (Vitis vinifera var. Bobal): Influence of drying conditions. J Food Eng 101:49–58González-García J, Sáez V, Tudela I, Díez-Garcia MI, Esclapez MD, Louisnard O (2010) Sonochemical treatment of water polluted by chlorinated organocompounds. A review. Water 2:28–74Handa SS, Preet S, Khanuja S, Longo G, Rakesh DD (2008) Extraction Technologies for Medicinal and Aromatic Plants. United Nations Industrial Development Organization and the International Centre for Science and High Technology, TriesteHemwimol S, Pavasant P, Shotipruk A (2006) Ultrasound-assisted extraction of anthraquinones from roots of Morinda citrifolia. Ultrason Sonochem 13:543–548Hielscher (2011) Teltow http:// www.hielscher.com . Accessed 10 Jan 2011Hu Y, Wang T, Wang M, Han S, Wan P, Fan M (2008) Extraction of isoflavonoids from Pueraria by combining ultrasound with microwave vacuum. Chem Engin Process 47:2256–2261Ince NH, Tezcanli G, Belen RK, Apikyan PG (2001) Ultrasound as a catalyzer of aqueous reaction systems: the state of the art and environmental applications. Appl Catal B 29:167–176Jadhav D, Rekha BN, Gogate PR, Rathod VK (2009) Extraction of vanillin from vanilla pods: a comparison study of conventional soxhlet and ultrasound assisted extraction. J Food Eng 93:421–426Ji J-b, Lu X-h, Cai M-q, Xu C-c (2006) Improvement of leaching process of Geniposide with ultrasound. Ultrason Sonochem 13:455–462Kanthale PM, Gogate PR, Pandit AB, Wilhelm AM (2003) Mapping of an ultrasonic horn: link primary and secondary effects of ultrasound. Ultrason Sonochem 10:331–335Karki B, Lamsal BP, Jung S, van Leeuwen JH, Pometto AL III, Grewell D, Khanal SK (2010) Enhancing protein and sugar release from defatted soy flakes using ultrasound technology. J Food Eng 96:270–278Kardos N, Luche J-L (2001) Sonochemistry of carbohydrate compounds. Carbohydr Res 332:115–131Kotronarou A, Mills G, Hoffmann MR (1991) Ultrasonic Irradiation of para-Nitrophenol in Aqueous Solution. J Phys Chem 95:3630–3638Kuijpers MWA, Kemmere MF, Keurentjes JTF (2002) Calorimetric study of the energy efficiency for ultrasound-induced radical formation. Ultrasonics 40:675–678Leighton TG (2007) What is ultrasound? Prog Biophys Mol Biol 93:3–83Leonelli C, Mason TJ (2010) Microwave and ultrasonic processing: now a realistic option for industry. Chem Eng Process 49:885–900Li H, Pordesimo L, Weiss J (2004) High intensity ultrasound-assisted extraction of oil from soybeans. Food Res Int 37:731–738Liu J, Li J-W, Tang J (2010) Ultrasonically assisted extraction of total carbohydrates from Stevia rebaudiana Bertoni and identification of extracts. Food Bioprod Process 88:215–221Lianfu Z, Zelong L (2008) Optimization and comparison of ultrasound/microwave assisted extraction (UMAE) and ultrasonic assisted extraction (UAE) of lycopene from tomatoes. Ultrason Sonochem 15:731–737Liazid A, Schwarz M, Varela RM, Palma M, Guillén DA, Brigui J, Macías FA, Barroso CG (2010) Evaluation of various extraction techniques for obtaining bioactive extracts from pine seeds. Food Bioprod Process 88:247–252Londoño-Londoño J, Rodrigues de Lima V, Lara O, Gil A, Crecsynski Pasa TB, Arango GJ, Ramirez Pineda JR (2010) Clean recovery of antioxidant flavonoids from citrus peel: optimizing an aqueous ultrasound-assisted extraction method. Food Chem 119:81–87Lou Z, Wang H, Zhang M, Wang Z (2010) Improved extraction of oil from chickpea under ultrasound in a dynamic system. J Food Eng 98:13–18Louisnard O, González-García J, Tudela I, Klima J, Sáez V, Vargas-Hernández Y (2009) FEM simulation of a sono-reactor accounting for vibrations of the boundaries. Ultrason Sonochem 16:250–259Luque de Castro MD, Priego-Capote F (2007) Analytical Applications of Ultrasound, Vol. 26, Techniques and Instrumentation in Analytical Chemistry. Elsevier Science, AmsterdamMa Y, Ye X, Hao Y, Xu G, Xu G, Liu D (2008) Ultrasound-assisted extraction of hesperidin from Penggan (Citrus reticulata) peel. Ultrason Sonochem 15:227–232Ma Y, Chen J-C, Liu Dong-Hong, Ye X-Q (2009) Simultaneous extraction of phenolic compounds of citrus peel extracts: effect of ultrasound. Ultrason Sonochem 16:57–62Makino K, Mossoba MM, Riesz P (1982) Chemical effects of ultrasound on aqueous solutions. Evidence for hydroxyl and hydrogen free radicals (.cntdot. OH and. cntdot. H) by spin trapping. J Chem Soc 104:3537–3539Margulis MA, Margulis IM (2003) Calorimetric method for measurement of acoustic power absorbed in a volume of liquid. Ultrason Sonochem 10:343–345Martin CJ, Law ANR (1983) Design of thermistor probes for measurement of ultrasound intensity distributions. Ultrasonics 21:85–90Mason TJ, Lorimer JP, Bates DM, Zhao Y (1994) Dosimetry in sonochemistry: the use of aqueous terephthalate ion as a fluorescence monitor. Ultrason Sonochem 1:91–95Meinhardt (2011) Leipzig. http://www.meinhardt-ultraschall.de . Accessed 10 Jan 2011Montalbo-Lomboy M, Khanal SK, van Leeuwen JH, Raman DR, Dunn L Jr, Grewell D Jr (2010) Ultrasonic pretreatment of corn slurry for saccharification: a comparison of batch and continuous Systems. Ultrason Sonochem 17:939–946Mulet A, Cárcel JA, Sanjuán N, Bon J (2003) New food drying technologies. Use of ultrasound. Food Sci Technol Int 9:215–221Naguleswaran S, Vasanthan T (2010) Dry milling of field pea (Pisum sativum L.) groats prior to wet fractionation influences the starch yield and purity. Food Chem 118:627–633Orozco-Solano M, Ruiz-Jiménez J, Luque de Castro MD (2010) Ultrasound-assisted extraction and derivatization of sterols and fatty alcohols from olive leaves and drupes prior to determination by gas chromatography–tandem mass spectrometry. J Chromatogr A 1217:1227–1235Patist A, Bates D (2008) Ultrasonic innovations in the food industry: from the laboratory to commercial production. Innovative Food Sci Emerg Technol 9:147–154Price GJ (1990) The use of ultrasound for the controlled degradation of polymer solutions. In: Mason TJ (ed) Advances in sonochemistry, vol 1. Jai Press, Cambridge, pp 231–287Riener J, Noci G, Cronin DA, Morgan DJ, Lyng JG (2010) A comparison of selected quality characteristics of yoghurts prepared from thermosonicated and conventionally heated milks. Food Chem 119:1108–1113Riera E, Golás Y, Blanco A, Gallego JA, Blasco M, Mulet A (2004) Mass transfer enhancement in supercritical fluids extraction by means of power ultrasound. Ultrason Sonochem 11:241–244Riera E, Blanco A, García J, Benedito J, Mulet A, Gallego-Juárez JA, Blasco M (2010) High-power ultrasonic system for the enhancement of mass transfer in supercritical CO2 extraction processes. Physics Procedia 3:141–146Roldán-Gutiérrez JM, Ruiz-Jiménez J, Luque de Castro MD (2008) Ultrasound-assisted dynamic extraction of valuable compounds from aromatic plants and flowers as compared with steam distillation and superheated liquid extraction. Talanta 75:1369–1375Romdhane M, Gourdon C (2002) Investigation in solid–liquid extraction: influence of ultrasound. Chem Eng J 87:11–19Rong L, Kojima Y, Koda S, Nomura H (2008) Simple quantification of ultrasonic intensity using aqueous solution of phenolphthalein. Ultrason Sonochem 8:11–15Sáez V, Frias-Ferrer A, Iniesta J, Gonzalez-Garcıa J, Aldaz A, Riera E (2005) Chacterization of a 20 kHz sonoreactor. Part I: analysis of mechanical effects by classical and numerical methods. Ultrason Sonochem 12:59–65Sáez V, Frias-Ferrer A, Iniesta J, Gonzalez-Garcıa J, Aldaz A, Riera E (2005) Characterization of a 20 kHz sonoreactor. Part II: analysis of chemical effects by classical and electrochemical methods. Ultrason Sonochem 12:67–72Sahena F, Zaidul ISM, Jinap S, Karim AA, Abbas KA, Norulaini NAN, Omar AKM (2009) Application of supercritical CO2 in lipid extraction–A review. J Food Eng 95:240–253Science Direct Database (2011) www.sciencedirect.com (Data of consulting: February 2011)Soria AC, Villamiel M (2010) Effect of ultrasound on the technological properties and bioactivity of food: a review. Trends Food Sci Technol 21:323–331Starmans DAJ, Nijhuis HH (1996) Extraction of secondary metabolites from plant material: a review. 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    Determination of the number of J/ψ events with J/ψ → inclusive decays

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    Two-photon widths of the χ c0,2 states and helicity analysis for χ c2→γγ

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    Based on a data sample of 106×106 ψ ′ events collected with the BESIII detector, the decays ψ ′→γχ c0,2, χ c0,2→γγ are studied to determine the two-photon widths of the χ c0,2 states. The two-photon decay branching fractions are determined to be B(χ c0→γγ)=(2. 24±0.19±0.12±0.08)×10 -4 and B(χ c2→γγ)=(3.21±0.18±0. 17±0.13)×10 -4. From these, the two-photon widths are determined to be Γ γγ(χ c0)=(2. 33±0.20±0.13±0.17)keV, Γ γγ(χ c2)=(0.63±0.04±0. 04±0.04)keV, and R=Γ γγ(χ c2)/ Γ γγ(χ c0)=0.271±0. 029±0.013±0.027, where the uncertainties are statistical, systematic, and those from the PDG B(ψ ′→γχ c0,2) and Γ(χ c0,2) errors, respectively. The ratio of the two-photon widths for helicity λ=0 and helicity λ=2 components in the decay χ c2→γγ is measured for the first time to be f 0/2=Γγγλ= 0(χ c2)/Γγγλ=2(χ c2)=0. 00±0.02±0.02. © 2012 American Physical Society.published_or_final_versio

    Search for a light exotic particle in J/psi radiative decays

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    Using a data sample containing 1.06x10^8 psi' events collected with the BESIII detector at the BEPCII electron-positron collider, we search for a light exotic particle X in the process psi' -> pi^+ pi^- J/psi, J/psi -> gamma X, X -> mu^+ mu^-. This light particle X could be a Higgs-like boson A^0, a spin-1 U boson, or a pseudoscalar sgoldstino particle. In this analysis, we find no evidence for any mu^+mu^- mass peak between the mass threshold and 3.0 GeV/c^2. We set 90%-confidence-level upper limits on the product-branching fractions for J/psi -> gamma A^0, A^0 -> mu^+ mu^- which range from 4x10^{-7} to 2.1x10^{-5}, depending on the mass of A^0, for M(A^0)<3.0 GeV/c^2. Only one event is seen in the mass region below 255 MeV/c^2 and this has a mu^+mu^- mass of 213.3 MeV/c^2 and the product branching fraction upper limit 5x10^{-7}.Comment: 7 pages, 3 figures, submitted to Physical Review
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