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Preparative Separation and Identification of the Flavonoid Phlorhizin from the Crude Extract of Lithocarpus Polystachyus Rehd  [PDF]
Huaqiang Dong,Zhengxiang Ning,Lijing Yu,Lin Li,Lichao Lin,Jianbo Huang
Molecules , 2007, DOI: 10.3390/12030552
Abstract: The flavonoid phlorhizin is abundant in the leaves of Sweet Tea(ST, Lithocarpus Polystachyus Rehd). Phlorhizinwas preparatively separated and purified from a crude ST extract containing 40% total flavonoids by static adsorption and dynamic desorption on ADS-7 macroporous resin and neutral alumina column chromatography. Only water and ethanol were used as solvents and eluants throughout the whole separation and purification process. Using a phlorhizin standard as the reference compound, the target compound separated from the crude ST extracts was analyzed by thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and electrosprayionization mass spectrometry (EIS-MS) and identified as 99.87% pure (by HPLC-UV) phlorhizin. The results showed that 10g of the targetcompound could be obtained from 40g of the crude extracts in a single operation, indicating a 40% recovery. Therefore, this represents an efficientand environmentally-friendly technology for separating and purifying phlorhizinfrom ST leaves.
Spatial variability more influential than soil pH and land relief on thermophilous vegetation in overgrown coppice oak forests
Tomasz H. Szymura,Magdalena Szymura
Acta Societatis Botanicorum Poloniae , 2013, DOI: 10.5586/asbp.2013.003
Abstract: The overgrown coppice oak forests that cover the southern slopes beneath the foothills of the Sudetes (Silesia, Central Europe) are considered to be Euro-Siberian steppic woods with a Quercus sp. habitat (91I0): a priority habitat in the European Union, according to the Natura 2000 system. In subcontinental parts of Central Europe, thermophilous oak forest vegetation is found extrazonally; its presence, in the study site, is related to previous coppice management. In this paper we explore the differentiation of the vegetation caused both by land-relief derived variables (potential heat load, slope inclination and exposition, soil depth) and soil pH, as well as spatial processes. The data on the vegetation were collected from 117 regularly arranged sampling plots, located in three mountain ranges. The vegetation consisted of a mixture of species considered as typical for different habitats (mesophilous forests, acidophilous forests, thermophilous oak forests, grassland, thermophilous fringes and mesophilous mantle) and was relatively rich in species. Many of the species found were rare and are protected in Poland. The results of the bioindication, on the basis of Ellenberg indicator values, suggest the pH gradient to be the most important, followed by the insolation/moisture gradient, to the differentiation of the studied vegetation. The thermophilous oak forests seem to occupy the niche between acidophilous and mesophilous forest. However the decomposition of spatial variation, assessed on the basis of semivariance values of the vegetation similarity coefficient (frequency index), emphasizes a strong differentiation of vegetation between sites and mountain ranges. The results of canonical correspondence analysis, performed on a spatially stratified sub-set of the data, revealed a stronger effect caused by spatial variation (32.7% of explained species variation) than environmental variables, such as soil pH and potential heat load (13.1%). Since the shared variation was low (1.8%), it showed a strong influence of spatial processes, revealing the effect of the local species pool.
Role of Cyperus rotundus oil in decreasing hair growth
GHADA FAROUK ABD EL-KAREAM
Journal of Intercultural Ethnopharmacology , 2012, DOI: 10.5455/jice.20120626100304
Abstract: Background: There is a lack on the value of Egyptian Cyperus rotundus essential oil in the treatment of Androgenic hair. Aim: To evaluate the efficacy and safety of application Egyptian Cyperus rotundus essential oil in comparison to 0.9% saline on androgenic hair. Patients & Methods: Ninety one female patients with Androgenic hair (hirsutism and axillary hair) completed the study. They were randomly assigned to two groups: group I (active group) (n=47) and group II (control group) (n=44). Patients used topical Cyperus rotundus essential oil for six months and were evaluated at 6th month. Results: The topical Cyperus rotundus oil was significantly more effective (p<0.05) than placebo with out side effects. This result was proved by three assessment methods; difference in hair count, independent observer assessment and patients self assessment. Conclusion: The topical Egyptian Cyperus rotundus essential oil is an effective method in treating moderate degrees of hirsutism and axillary hair. But without affecting serum testosterone. This study is the first report on using Cyperus rotundus essential oil for decreasing hair growth. [J Intercult Ethnopharmacol 2012; 1(2.000): 111-118]
Problem-Elephant Translocation: Translocating the Problem and the Elephant?  [PDF]
Prithiviraj Fernando, Peter Leimgruber, Tharaka Prasad, Jennifer Pastorini
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0050917
Abstract: Human-elephant conflict (HEC) threatens the survival of endangered Asian elephants (Elephas maximus). Translocating “problem-elephants” is an important HEC mitigation and elephant conservation strategy across elephant range, with hundreds translocated annually. In the first comprehensive assessment of elephant translocation, we monitored 16 translocations in Sri Lanka with GPS collars. All translocated elephants were released into national parks. Two were killed within the parks where they were released, while all the others left those parks. Translocated elephants showed variable responses: “homers” returned to the capture site, “wanderers” ranged widely, and “settlers” established home ranges in new areas soon after release. Translocation caused wider propagation and intensification of HEC, and increased elephant mortality. We conclude that translocation defeats both HEC mitigation and elephant conservation goals.
Rethinking the basic conservation unit and associated protocol for augmentation of an "endangered" caribou population: An opinion
Frank L. Miller,Samuel J. Barry,Wendy A. Calvert,Keri A. Zittlau
Rangifer , 2007,
Abstract: Use of the subspecies as the basic unit in the conservation of endangered caribou (Rangifer tarandus) would produce a “melting pot” end-product that would mask important genotypic, phenotypic, ecological, and behavioral variations found below the level of the subspecies. Therefore, we examined options for establishing the basic conservation unit for an endangered caribou population: use of subspecies based on taxonomy, subspecies based solely on mtDNA, Evolutionarily Significant Units, and the geographic population. We reject the first three and conclude that the only feasible basic unit for biologically and ecologically sound conservation of endangered caribou in North America is the geographic population. Conservation of endangered caribou at the level of the geographic population is necessary to identify and maintain current biodiversity. As deliberations about endangered caribou conservation often involve consideration of population augmentation, we also discuss the appropriate augmentation protocol for conserving biodiversity. Management of a critically endangered caribou population by augmentation should only be initiated after adequate study and evaluation of the genotype, phenotype, ecology, and behavior for both the endangered caribou and the potential‘donor’ caribou to prevent the possible ‘contamination’ of the endangered caribou. Translocation of caribou into an endangered population will have failed, even if the restocking efforts succeed, if the donor animals functionally alter the population’s gene pool or phenotype, or alter the ecological and behavioral adaptations of individuals in the endangered population. Most importantly, a seriously flawed restocking would risk irreversibly altering those functional characteristics of caribou in an endangered population that make them distinct and possibly unique. It might even result in the loss of the endangered population, thus eliminating a uniquely evolved line from among the caribou species.
Wound healing activity of cyperus rotundus linn.
Puratchikody A,Devi C,Nagalakshmi G
Indian Journal of Pharmaceutical Sciences , 2006,
Abstract: The present study was aimed to evaluate the wound healing activity of extract of tuber parts of Cyperus rotundus . It is a well-known plant in Indian traditional medicine. On the basis of traditional use and literature references, this plant was selected for evaluation of wound healing potential. An alcoholic extract of tuber parts of Cyperus rotundus was examined for wound healing activity in the form of ointment in three types of wound models on rats: the excision, the incision and dead space wound model. The extract ointments showed considerable difference in response in all the above said wound models as comparable to those of a standard drug nitrofurazone ointment (0.2% w/w NFZ) in terms of wound contracting ability, wound closure time and tensile strength.
BUSCANDO UM BIOHERBICIDA CONTRA Cyperus sp (tiririca)
Cristine Benfatti Gonzalez,Iracema de Oliveira Moraes
Holos Environment , 2001,
Abstract: As an alternative to conventional control of Cyperus sp (herbaceousnutsedge), with chemical products, it rises the biological control, making use of phytopathogenic microorganisms. As results of the whole production of Cercospora henningsii e Cercospora caricis by fermentation in potato-dextrose (PD) liquid medium, it was observed that both species obtained the optimum growth at 36o C. C. henningsii attained the best value after a period of 72 h of fermentation and C. caricis attained it after 60 h. The field experiments, against Cyperus sp (nutsedge), with the obtained products by liquid fermentation of Cercospora sp (C. henningsii and/or C. caribaea), andwith the use of "wet chamber", proved the pathogenic potential bioherbicide of these microorganisms. = Como alternativa ao controle convencional do Cyperus sp (tiririca) usando produtos químicos, surge o controle biológico, empregando-se microrganismos fitopatógenos. Como resultados da produ o massal de Cercospora henningsii eCercospora caricis através de cultivo submerso em meio de cultura batata-dextrose (BD), observou-se que ambas espécies obtiveram um crescimento ótimo a 36o C, sendo que para C. henningsii se deu com 72 h de fermenta o e para C. caricis com 60 h. Os experimentos de campo, bem como os de Camara úmida, contra Cyperus sp (tiririca),com os produtos obtidos pelo cultivo submerso de Cercospora sp (C. henningsii e/ou C. caribaea), demonstraram a patogenicidade, ou seja, o potencial bioherbicida desses microrganismos.
Efeito do extrato de Cyperus rotundus na rizogênese Effect of Cyperus rotundus extract on rhizogenes
Matheus Fonseca de Souza,Eldelon de Oliveira Pereira,Madlles Queiroz Martins,Ruimário Inácio Coelho
Revista de Ciências Agrárias , 2012,
Abstract: A Cyperus rotundus é uma planta herbácea perene que se multiplica sexuadamente por semente e assexuadamente por bulbos, tubérculos e rizomas subterraneos. O objetivo principal desse trabalho foi avaliar o efeito do extrato de Cyperus rotundus no enraizamento de folhas de Solanum lycopersicum. Os estudos foram realizados no laboratório de química e na casa de vegeta o, ambos no CCA/Alegre/ES. O experimento foi realizado em duas etapas: a confec o do extrato a partir de 2 g de tiririca em 40 mL de solvente (metanol PA, etanol PA, água destilada), para o teste do extrato no enraizamento empregou-se o delineamento inteiramente casualizado com 17 tratamentos com 6 repeti es e 6 plantas por repeti o. Dentre os tratamentos, os que promoveram o enraizamento foram os extratos aquosos 100, 50 e 25%, sendo que o extrato aquoso 50% foi o que demonstrou o melhor resultado, se assemelhando ao controle positivo AIB (ácido indolbutiríco). Os resultados obtidos com o uso do extrato de Cyperus rotundus, parecem ser promissores. Porém s o necessários novos estudos, para demonstrar a utilidade prática do extrato Cyperus rotundus no enraizamento. The Cyperus rotundus is an herbaceous perennial plant that multiplies sexually from seed and asexually from bulbs, tubers and underground rhizomes. Thus, the present work aimed to assay the effect of C. rotundus extract on the rhizogenesis of Solanum lycopersicum leaves. The studies were performed in the laboratory of chemistry and greenhouse, at in CCA/Alegre/ES. The extract was prepared from 2g of C. rotundus and 40mL of solvent (methanol PA, ethanol PA and distilled water). The experimental design utilized to test the extract’s effect on rhizogenesis was entirely random, containing 17 treatments, 6 replicates and 6 plants per replicate. The effective treatments were obtained with aqueous extracts at 100, 50 and 25%. However, the best result was observed for the aqueous extract of 50%, similar to the positive control AIB. The results obtained with the use of Cyperus rotundus’ extract, seem to be promising, although further studies are needed to demonstrate the usefulness of Cyperus rotundus’ extract on rhizogenesis.
Dynamics of forced biopolymer translocation  [PDF]
V. V. Lehtola,R. P. Linna,K. Kaski
Physics , 2009, DOI: 10.1209/0295-5075/85/58006
Abstract: We present results from our simulations of biopolymer translocation in a solvent which explain the main experimental findings. The forced translocation can be described by simple force balance arguments for the relevant range of pore potentials in experiments and biological systems. Scaling of translocation time with polymer length varies with pore force and friction. Hydrodynamics affects this scaling and significantly reduces translocation times.
Polymer Translocation in Crowded Environments  [PDF]
Ajay Gopinathan,Yong Woon Kim
Physics , 2007, DOI: 10.1103/PhysRevLett.99.228106
Abstract: We study the effect of the crowded nature of the cellular cytoplasm on the translocation of a polymer through a pore in a membrane. By systematically treating the entropic penalty due to crowding, we show that the translocation dynamics are significantly altered, leading to novel scaling behaviors of the translocation time in terms of chain length. We also observe new and qualitatively different translocation regimes depending upon the extent of crowding, transmembrane chemical potential asymmetry, and polymer length.
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