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Production of Activated Carbon and Characterization from Snail Shell Waste (Helix pomatia)  [PDF]
Rhoda Habor Gumus, Ideyonbe Okpeku
Advances in Chemical Engineering and Science (ACES) , 2015, DOI: 10.4236/aces.2015.51006
Abstract: Snail shell waste (Helix pomatia) has been evaluated as raw material for the preparation of activated carbon using ZnCl2 and CaCl2 with the temperature ranging from 500°C to 800°C. The activated carbon prepared was characterized, showing effect of temperature on ash content, pore volume and porosity. The adsorption isotherm for methylene blue was carried out on the activated carbon in a batch study. The adsorbent exhibited excellent adsorption for methylene blue. The experimental data were used for both Langmuir and Freundlich models. The adsorption coefficients of Langmuir isotherm were found to be 0.996 and 0.957 for CaCl2 and ZnCl2 while 0.969 and 0.962 were obtained for the Freundlich isotherm respectively. The value of RL was found to be 0.75 and 0.38 for samples CC and ZZ respectively, which is an indication that activated carbon impregnated with CaCl2 and ZnCl2 is favourable for adsorption of methylene blue under the conditions used in this study.
Some quality parameters of land snail meat - Helix pomatia  [PDF]
Tojagi? Slobodan N.,Kevre?an ?arko S.,Jokanovi? Marija R.
Veterinarski Glasnik , 2004, DOI: 10.2298/vetgl0402157t
Abstract: Considering the tradition in our regions to collect land snails (Helix pomatia) for export, which is "disrupted" by social control resulting in limited possibilities to develop this attractive activity, there is a great interest lately for land snail breeding and fattening at farms. For this reason it is necessary to investigate systematically the possibilities to develop this activity in a longer period and in larger areas. The first investigations, although covering only nutritive and health safety aspects of the edible parts yielded the results presented in this work. Chemical composition, the content of some elements and organochlorine insecticides were followed as unavoidable in human living and environment.
Modification of the acetylcholine-induced current of the snail Helix pomatia L. by fast temperature changes
Nedeljkovi? M.,Kartelija Gordana,Radenovi? Lidija
Archives of Biological Sciences , 2005, DOI: 10.2298/abs0503181n
Abstract: Using the single electrode voltage clamp method, we found that acetylcholine (aCh) induces transient inward dose-dependent current on the membrane of the identified Helix pomatia Br neuron. We analyzed the effects of fast cooling and heating as well as thermal acclimation on the aCh inward current. the experiments were conducted on active and dormant snails acclimated to either 20 or 7°C for at least four weeks. the Hill coefficient remained approximately 1 in all cases, which means that there is a single aCh binding site on the membrane. Fast temperature alternations induce binding affinity changes. in the work presented, we analyzed the effects of cooling on the aCh-induced inward current. the amplitude of aCh-induced inward current was markedly reduced after cooling, and the speed of decay of the aCh response was lower.
Can the environment induce intra-variety changes of Helix pomatia conchological features?  [PDF]
Dragos NICA,Marioara Nicoleta FILIMON,Aurica Breica BOROZAN,Doru VINTILA
Analele Universitatii din Oradea, Fascicula Biologie , 2011,
Abstract: Inter- and intra-specific genetically and phenotypically determined variations in snail morphological features are well documented. The same may be true even within the same species variety. The snails (Helix pomatia var. Banatica) were collected from two distinct sites, placed 100 km one from another and characterized by different climatic conditions (rainfall level, altitude, annual average temperature, and subtype of temperate climate): Oravi a and Timi oara area. Using bi - and tridimensional data processing, statistical, and biochemical analyses we assessed the cumulated actions of environmental factors on intra - variety changes of shell morphological features in relation to origin area. Formula proposed for shell tri-dimensional processing (shell volume) provided a reliable and faster method to assess variations among shell height, width, and depth than the multiple analyses of each feature apart. Similarly, aperture bi-dimensional processing (aperture area) successfully replaced the separated statistical analyses of aperture height and depth. Most biometric features, excepting shell thickness, presented a linked and proportional pattern among themselves. In addition, the sense of these relationships (direct or converse proportional) for shell height, width, and depth seemed to vary depending on location. We demonstrated that shell volume and aperture area tend to be larger in areas with higher annual rainfall level, altitude, and mean average temperature. Oppositely, shell thickness displayed a conversed relationship,possibly related to higher calcium content registered for the same population. Overall, our findings suggest that within the samespecies variety gastropod shells follow a genetic pattern of growing that allow the preservation of their geometric shape irrespectiveof the environmental conditions.
Helix pomatia endobr?nquico. Aspira??o de um corpo estranho muito pouco frequente.
Costa,A. Santos; Afonso,Abel;
Revista Portuguesa de Pneumologia , 2008,
Abstract: foreign-body aspiration is a frequent occurrence in children, but much less common in adults. the authors present a case report of a 57 year old adult, without any neurological disease, who aspirated a snail (helix pomatia) during a meal.
Preliminary investigations on accompanied invertebrate fauna of farms of Helix pomatia Linnaeus and Helix aspersa O. F. Müller (Helicidae, Gastropoda) in Serbia and Montenegro
?ur?i? Sre?ko B.,Topalovi? D.,Jakovljevi? Jelena,Brajkovi? Miloje M.
Archives of Biological Sciences , 2004, DOI: 10.2298/abs0404089c
Abstract: Altogether 18 species of invertebrates were evidented during investigations on snail farms of Helix pomatia Linnaeus and Helix aspersa O. F. Müller in Serbia and Montenegro. Of these, 9 species from 8 genera were registered from Serbia, and 9 species from 9 genera were collected from Montenegro. Invertebrate material mostly pertained to insects (orders Coleoptera and Heteroptera) and crustaceans (order Isopoda). Data about exact ecological status of all species of collected invertebrates were also presented. Also we notify clear distinctions between all analyzed species in the type of feeding (the cases of helicophagy, zoophagy, phytophagy, and mixophagy).
Effect of alternating the magnetic feld on phosphate metabolism in the nervous system of Helix pomatia
Nikolic,Ljiljana M; Rokic,Milos B; Todorovic,Natasa V; Kartelija,Gordana S; Nedeljkovic,Miodrag S; Zakrzewska,Joanna S;
Biological Research , 2010, DOI: 10.4067/S0716-97602010000200012
Abstract: the effect of extremely low frequency magnetic felds (50 hz, 0.5 mt) - elf-mf, on phosphate metabolism has been studied in the isolated ganglions of the garden snail helix pomatia, after 7 and 16 days of snail exposure to elf-mf. the infuence of elf-mf on the level of phosphate compounds and intracellular ph was monitored by 31p nmr spectroscopy. furthermore, the activity of enzymes involved in phosphate turnover, total atpases, na+/k+-atpase and acid phosphatase has been measured. the exposure of snails to the elf-mf for the period of 7 days shifted intracellular ph toward more alkaline conditions, and increased the activity of investigated enzymes. prolonged exposure to the elf-mf for the period of 16 days caused a decrease of pcr and atp levels and decreased enzyme activity, compared to the 7-day treatment group. our results can be explained in terms of: 1. increase in phosphate turnover by exposure to the elf-mf for the period of 7 days, and 2. adaptation of phosphate metabolism in the nervous system of snails to prolonged elf-mf exposure.
Effect of alternating the magnetic feld on phosphate metabolism in the nervous system of Helix pomatia
Ljiljana M Nikolic,Milos B Rokic,Natasa V Todorovic,Gordana S Kartelija
Biological Research , 2010,
Abstract: The effect of extremely low frequency magnetic felds (50 Hz, 0.5 mT) - ELF-MF, on phosphate metabolism has been studied in the isolated ganglions of the garden snail Helix pomatia, after 7 and 16 days of snail exposure to ELF-MF. The infuence of ELF-MF on the level of phosphate compounds and intracellular pH was monitored by 31P NMR spectroscopy. Furthermore, the activity of enzymes involved in phosphate turnover, total ATPases, Na+/K+-ATPase and acid phosphatase has been measured. The exposure of snails to the ELF-MF for the period of 7 days shifted intracellular pH toward more alkaline conditions, and increased the activity of investigated enzymes. Prolonged exposure to the ELF-MF for the period of 16 days caused a decrease of PCr and ATP levels and decreased enzyme activity, compared to the 7-day treatment group. Our results can be explained in terms of: 1. increase in phosphate turnover by exposure to the ELF-MF for the period of 7 days, and 2. adaptation of phosphate metabolism in the nervous system of snails to prolonged ELF-MF exposure.
Bioaccumulative and conchological assessment of heavy metal transfer in a soil-plant-snail food chain
Dragos V Nica, Marian Bura, Iosif Gergen, Monica Harmanescu, Despina-Maria Bordean
Chemistry Central Journal , 2012, DOI: 10.1186/1752-153x-6-55
Abstract: Significantly higher amounts of HMs were accumulated in snail hepatopancreas and not in foot. Cu, Zn, and Cd have biomagnified in the snail body, particularly in the hepatopancreas. In contrast, Pb decreased when going up into the food chain. Zn, Cd, and Pb correlated highly with each other at all levels of the investigated food chain. Zn and Pb exhibited an effective soil–plant transfer, whereas in the snail body only foot Cu concentration was correlated with that in soil. There were significant differences among sampling sites for WN, SH, and RSH when compared with reference snails. WN was strongly correlated with Cd and Pb concentrations in nettle leaves but not with Cu and Zn. SH was independent of HM concentrations in soil, snail hepatopancreas, and foot. However, SH correlated negatively with nettle leaves concentrations for each HM except Cu. In contrast, RSH correlated significantly only with Pb concentration in hepatopancreas.The snail hepatopancreas accumulates high amounts of HMs, and therefore, this organ can function as a reliable biomarker for tracking HM bioavailability in soil. Long-term exposure to HMs via contaminated food might influence the variability of shell traits in snail populations. Therefore, our results highlight the Roman snail (Helix pomatia) potential to be used in environmental monitoring studies as bioindicator of HM pollution.The growing awareness and concerns about the impact of global pollution on human lives and health have triggered scientists interest to characterize and monitor the quality of the biota. Environmental monitoring is defined as “a time series of measurements of physical, chemical, and/or biological variables, designed to answer questions about environmental change” [1]. Chemical monitoring relies on specific analytical techniques (e.g., titrimetric methods, atomic spectroscopy, mass spectrometry, chromatography) to measure the precise level of specific pollutants in natural environments, but it cannot account fo
Nota sobre a ocorrência do parasito Riccardoella limacum (Schrank, 1781) (Acari, ereynetidae) em cria??es de escargot (Helix pomatia L. e H . aspersa L.) no Brasil
Flechtmann, Carlos H.W.;Baggio, Domingos;
Anais da Escola Superior de Agricultura Luiz de Queiroz , 1985, DOI: 10.1590/S0071-12761985000100005
Abstract: the slug-mite, riccardoella limacum (schrank) is reported from helix aspersa l. and h.pomatia l. farms in belo horizonte, minas gerais and in embu, s?o paulo, brazil. death of escargots is correlated with the presence of high numbers of this mite.
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