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Mendel Friedman - One of the best experts on this subject based on the ideXlab platform.
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effects of Allspice cinnamon and clove bud essential oils in edible apple films on physical properties and antimicrobial activities
Journal of Food Science, 2009Co-Authors: Carl W Olsen, Roberto J Avenabustillos, Tara H Mchugh, Carol Levin, Mendel FriedmanAbstract:ABSTRACT: Essential oils (EOs) derived from plants are rich sources of volatile terpenoids and phenolic compounds. Such compounds have the potential to inactivate pathogenic bacteria on contact and in the vapor phase. Edible films made from fruits or vegetables containing EOs can be used commercially to protect food against contamination by pathogenic bacteria. EOs from cinnamon, Allspice, and clove bud plants are compatible with the sensory characteristics of apple-based edible films. These films could extend product shelf life and reduce risk of pathogen growth on food surfaces. This study evaluated physical properties (water vapor permeability, color, tensile properties) and antimicrobial activities against Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes of Allspice, cinnamon, and clove bud oils in apple puree film-forming solutions formulated into edible films at 0.5% to 3% (w/w) concentrations. Antimicrobial activities were determined by 2 independent methods: overlay of the film on top of the bacteria and vapor phase diffusion of the antimicrobial from the film to the bacteria. The antimicrobial activities against the 3 pathogens were in the following order: cinnamon oil > clove bud oil > Allspice oil. The antimicrobial films were more effective against L. monocytogenes than against the S. enterica. The oils reduced the viscosity of the apple solutions and increased elongation and darkened the colors of the films. They did not affect water vapor permeability. The results show that apple-based films with Allspice, cinnamon, or clove bud oils were active against 3 foodborne pathogens by both direct contact with the bacteria and indirectly by vapors emanating from the films.
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Antibacterial Effects of Allspice, Garlic, and Oregano Essential Oils in Tomato Films Determined by Overlay and Vapor-Phase Methods
Journal of food science, 2009Co-Authors: Carl W Olsen, Tara H Mchugh, Carol Levin, Roberto J. Avena-bustillos, Robert E. Mandrell, Mendel FriedmanAbstract:Physical properties as well as antimicrobial activities against Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes of Allspice, garlic, and oregano essential oils (EOs) in tomato puree film-forming solutions (TPFFS) formulated into edible films at 0.5% to 3% (w/w) concentrations were investigated in this study. Antimicrobial activities were determined by 2 independent methods: overlay of the film on top of the bacteria and vapor-phase diffusion of the antimicrobial from the film to the bacteria. The results indicate that the antimicrobial activities against the 3 pathogens were in the following order: oregano oil > Allspice oil > garlic oil. Listeria monocytogenes was less resistant to EO vapors, while E. coli O157:H7 was more resistant to EOs as determined by both overlay and vapor-phase diffusion tests. The presence of plant EO antimicrobials reduced the viscosity of TPFFS at the higher shear rates, but did not affect water vapor permeability of films. EOs increased elongation and darkened the color of films. The results of the present study show that the 3 plant-derived EOs can be used to prepare tomato-based antimicrobial edible films with good physical properties for food applications by both direct contact and indirectly by vapors emanating from the films.
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bactericidal activities of plant essential oils and some of their isolated constituents against campylobacter jejuni escherichia coli listeria monocytogenes and salmonella enterica
Journal of Food Protection, 2002Co-Authors: Mendel Friedman, Philip R Henika, Robert E. MandrellAbstract:An improved method of sample preparation was used in a microplate assay to evaluate the bactericidal activity levels of 96 essential oils and 23 oil compounds against Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica obtained from food and clinical sources. Bactericidal activity (BA50) was dee ned as the percentage of the sample in the assay mixture that resulted in a 50% decrease in CFU relative to a buffer control. Twenty-seven oils and 12 compounds were active against all four species of bacteria. The oils that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.009) were marigold, ginger root, jasmine, patchouli, gardenia, cedarwood, carrot seed, celery seed, mugwort, spikenard, and orange bitter oils; those that were most active against E. coli (with BA50 values ranging from 0.046 to 0.14) were oregano, thyme, cinnamon, palmarosa, bay leaf, clove bud, lemon grass, and Allspice oils; those that were most active against L. monocytogenes (with BA50 values ranging from 0.057 to 0.092) were gardenia, cedarwood, bay leaf, clove bud, oregano, cinnamon, Allspice, thyme, and patchouli oils; and those that were most active against S. enterica (with BA50 values ranging from 0.045 to 0.14) were thyme, oregano, cinnamon, clove bud, Allspice, bay leaf, palmarosa, and marjoram oils. The oil compounds that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.034) were cinnamaldehyde, estragole, carvacrol, benzaldehyde, citral, thymol, eugenol, perillaldehyde, carvone R, and geranyl acetate; those that were most active against E. coli (with BA50 values ranging from 0.057 to 0.28) were carvacrol, cinnamaldehyde, thymol, eugenol, salicylaldehyde, geraniol, isoeugenol, citral, perillaldehyde, and estragole; those that were most active against L. monocytogenes (with BA50 values ranging from 0.019 to 0.43) were cinnamaldehyde, eugenol, thymol, carvacrol, citral, geraniol, perillaldehyde, carvone S, estragole, and salicylaldehyde; and those that were most active against S. enterica (with BA50 values ranging from 0.034 to 0.21) were thymol, cinnamaldehyde, carvacrol, eugenol, salicylaldehyde, geraniol, isoeugenol, terpineol, perillaldehyde, and estragole. The possible signie cance of these results with regard to food microbiology is discussed.
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bactericidal activities of plant essential oils and some of their isolated constituents against campylobacter jejuni escherichia coli listeria monocytogenes and salmonella enterica
Journal of Food Protection, 2002Co-Authors: Mendel Friedman, Philip R Henika, Robert E. MandrellAbstract:An improved method of sample preparation was used in a microplate assay to evaluate the bactericidal activity levels of 96 essential oils and 23 oil compounds against Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica obtained from food and clinical sources. Bactericidal activity (BA50) was dee ned as the percentage of the sample in the assay mixture that resulted in a 50% decrease in CFU relative to a buffer control. Twenty-seven oils and 12 compounds were active against all four species of bacteria. The oils that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.009) were marigold, ginger root, jasmine, patchouli, gardenia, cedarwood, carrot seed, celery seed, mugwort, spikenard, and orange bitter oils; those that were most active against E. coli (with BA50 values ranging from 0.046 to 0.14) were oregano, thyme, cinnamon, palmarosa, bay leaf, clove bud, lemon grass, and Allspice oils; those that were most active against L. monocytogenes (with BA50 values ranging from 0.057 to 0.092) were gardenia, cedarwood, bay leaf, clove bud, oregano, cinnamon, Allspice, thyme, and patchouli oils; and those that were most active against S. enterica (with BA50 values ranging from 0.045 to 0.14) were thyme, oregano, cinnamon, clove bud, Allspice, bay leaf, palmarosa, and marjoram oils. The oil compounds that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.034) were cinnamaldehyde, estragole, carvacrol, benzaldehyde, citral, thymol, eugenol, perillaldehyde, carvone R, and geranyl acetate; those that were most active against E. coli (with BA50 values ranging from 0.057 to 0.28) were carvacrol, cinnamaldehyde, thymol, eugenol, salicylaldehyde, geraniol, isoeugenol, citral, perillaldehyde, and estragole; those that were most active against L. monocytogenes (with BA50 values ranging from 0.019 to 0.43) were cinnamaldehyde, eugenol, thymol, carvacrol, citral, geraniol, perillaldehyde, carvone S, estragole, and salicylaldehyde; and those that were most active against S. enterica (with BA50 values ranging from 0.034 to 0.21) were thymol, cinnamaldehyde, carvacrol, eugenol, salicylaldehyde, geraniol, isoeugenol, terpineol, perillaldehyde, and estragole. The possible signie cance of these results with regard to food microbiology is discussed.
Robert E. Mandrell - One of the best experts on this subject based on the ideXlab platform.
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Antibacterial Effects of Allspice, Garlic, and Oregano Essential Oils in Tomato Films Determined by Overlay and Vapor-Phase Methods
Journal of food science, 2009Co-Authors: Carl W Olsen, Tara H Mchugh, Carol Levin, Roberto J. Avena-bustillos, Robert E. Mandrell, Mendel FriedmanAbstract:Physical properties as well as antimicrobial activities against Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes of Allspice, garlic, and oregano essential oils (EOs) in tomato puree film-forming solutions (TPFFS) formulated into edible films at 0.5% to 3% (w/w) concentrations were investigated in this study. Antimicrobial activities were determined by 2 independent methods: overlay of the film on top of the bacteria and vapor-phase diffusion of the antimicrobial from the film to the bacteria. The results indicate that the antimicrobial activities against the 3 pathogens were in the following order: oregano oil > Allspice oil > garlic oil. Listeria monocytogenes was less resistant to EO vapors, while E. coli O157:H7 was more resistant to EOs as determined by both overlay and vapor-phase diffusion tests. The presence of plant EO antimicrobials reduced the viscosity of TPFFS at the higher shear rates, but did not affect water vapor permeability of films. EOs increased elongation and darkened the color of films. The results of the present study show that the 3 plant-derived EOs can be used to prepare tomato-based antimicrobial edible films with good physical properties for food applications by both direct contact and indirectly by vapors emanating from the films.
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bactericidal activities of plant essential oils and some of their isolated constituents against campylobacter jejuni escherichia coli listeria monocytogenes and salmonella enterica
Journal of Food Protection, 2002Co-Authors: Mendel Friedman, Philip R Henika, Robert E. MandrellAbstract:An improved method of sample preparation was used in a microplate assay to evaluate the bactericidal activity levels of 96 essential oils and 23 oil compounds against Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica obtained from food and clinical sources. Bactericidal activity (BA50) was dee ned as the percentage of the sample in the assay mixture that resulted in a 50% decrease in CFU relative to a buffer control. Twenty-seven oils and 12 compounds were active against all four species of bacteria. The oils that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.009) were marigold, ginger root, jasmine, patchouli, gardenia, cedarwood, carrot seed, celery seed, mugwort, spikenard, and orange bitter oils; those that were most active against E. coli (with BA50 values ranging from 0.046 to 0.14) were oregano, thyme, cinnamon, palmarosa, bay leaf, clove bud, lemon grass, and Allspice oils; those that were most active against L. monocytogenes (with BA50 values ranging from 0.057 to 0.092) were gardenia, cedarwood, bay leaf, clove bud, oregano, cinnamon, Allspice, thyme, and patchouli oils; and those that were most active against S. enterica (with BA50 values ranging from 0.045 to 0.14) were thyme, oregano, cinnamon, clove bud, Allspice, bay leaf, palmarosa, and marjoram oils. The oil compounds that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.034) were cinnamaldehyde, estragole, carvacrol, benzaldehyde, citral, thymol, eugenol, perillaldehyde, carvone R, and geranyl acetate; those that were most active against E. coli (with BA50 values ranging from 0.057 to 0.28) were carvacrol, cinnamaldehyde, thymol, eugenol, salicylaldehyde, geraniol, isoeugenol, citral, perillaldehyde, and estragole; those that were most active against L. monocytogenes (with BA50 values ranging from 0.019 to 0.43) were cinnamaldehyde, eugenol, thymol, carvacrol, citral, geraniol, perillaldehyde, carvone S, estragole, and salicylaldehyde; and those that were most active against S. enterica (with BA50 values ranging from 0.034 to 0.21) were thymol, cinnamaldehyde, carvacrol, eugenol, salicylaldehyde, geraniol, isoeugenol, terpineol, perillaldehyde, and estragole. The possible signie cance of these results with regard to food microbiology is discussed.
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bactericidal activities of plant essential oils and some of their isolated constituents against campylobacter jejuni escherichia coli listeria monocytogenes and salmonella enterica
Journal of Food Protection, 2002Co-Authors: Mendel Friedman, Philip R Henika, Robert E. MandrellAbstract:An improved method of sample preparation was used in a microplate assay to evaluate the bactericidal activity levels of 96 essential oils and 23 oil compounds against Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica obtained from food and clinical sources. Bactericidal activity (BA50) was dee ned as the percentage of the sample in the assay mixture that resulted in a 50% decrease in CFU relative to a buffer control. Twenty-seven oils and 12 compounds were active against all four species of bacteria. The oils that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.009) were marigold, ginger root, jasmine, patchouli, gardenia, cedarwood, carrot seed, celery seed, mugwort, spikenard, and orange bitter oils; those that were most active against E. coli (with BA50 values ranging from 0.046 to 0.14) were oregano, thyme, cinnamon, palmarosa, bay leaf, clove bud, lemon grass, and Allspice oils; those that were most active against L. monocytogenes (with BA50 values ranging from 0.057 to 0.092) were gardenia, cedarwood, bay leaf, clove bud, oregano, cinnamon, Allspice, thyme, and patchouli oils; and those that were most active against S. enterica (with BA50 values ranging from 0.045 to 0.14) were thyme, oregano, cinnamon, clove bud, Allspice, bay leaf, palmarosa, and marjoram oils. The oil compounds that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.034) were cinnamaldehyde, estragole, carvacrol, benzaldehyde, citral, thymol, eugenol, perillaldehyde, carvone R, and geranyl acetate; those that were most active against E. coli (with BA50 values ranging from 0.057 to 0.28) were carvacrol, cinnamaldehyde, thymol, eugenol, salicylaldehyde, geraniol, isoeugenol, citral, perillaldehyde, and estragole; those that were most active against L. monocytogenes (with BA50 values ranging from 0.019 to 0.43) were cinnamaldehyde, eugenol, thymol, carvacrol, citral, geraniol, perillaldehyde, carvone S, estragole, and salicylaldehyde; and those that were most active against S. enterica (with BA50 values ranging from 0.034 to 0.21) were thymol, cinnamaldehyde, carvacrol, eugenol, salicylaldehyde, geraniol, isoeugenol, terpineol, perillaldehyde, and estragole. The possible signie cance of these results with regard to food microbiology is discussed.
C Pérez-alonso - One of the best experts on this subject based on the ideXlab platform.
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Supercritical Extraction Process of Allspice Essential Oil
Journal of Chemistry, 2017Co-Authors: Yasvet Y. Andrade-avila, J Cruz-olivares, C Pérez-alonso, Ciro Humberto Ortiz-estrada, M.c. Chaparro-mercadoAbstract:Allspice essential oil was extracted with supercritical carbon dioxide (SC-CO2) in a static process at three different temperatures (308.15, 313.15, and 318.15 K) and four levels of pressure (100, 200, 300, and 360 bar). The amount of oil extracted was measured at intervals of 1, 2, 3, 4, 5, and 6 h; the most extraction yield reached was of 68.47% at 318.15 K, 360 bar, and 6 h of contact time. In this supercritical extraction process, the distribution coefficient ( ), the mean effective diffusion coefficient ( ), the energy of activation ( ), the thermodynamic properties ( , , and ), and the apparent solubility ( ) expressed as mass fraction (w/w) were evaluated for the first time. At the equilibrium the experimental apparent solubility data were successfully correlated with the modified Chrastil equation.
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Supercritical Extraction Process of Allspice Essential Oil
Hindawi Limited, 2017Co-Authors: Yasvet Y. Andrade-avila, C Pérez-alonso, Ciro Humberto Ortiz-estrada, Julian Cruz-olivares, María Del Carmen Chaparro MercadoAbstract:Allspice essential oil was extracted with supercritical carbon dioxide (SC-CO2) in a static process at three different temperatures (308.15, 313.15, and 318.15 K) and four levels of pressure (100, 200, 300, and 360 bar). The amount of oil extracted was measured at intervals of 1, 2, 3, 4, 5, and 6 h; the most extraction yield reached was of 68.47% at 318.15 K, 360 bar, and 6 h of contact time. In this supercritical extraction process, the distribution coefficient (KD), the mean effective diffusion coefficient (Def), the energy of activation (Ea), the thermodynamic properties (ΔG0, ΔH0, and ΔS0), and the apparent solubility (S) expressed as mass fraction (w/w) were evaluated for the first time. At the equilibrium the experimental apparent solubility data were successfully correlated with the modified Chrastil equation
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Modeling of lead (II) biosorption by residue of Allspice in a fixed-bed column
Chemical Engineering Journal, 2013Co-Authors: J Cruz-olivares, Carlos Barrera-díaz, Fernando Ureña-núñez, C Pérez-alonso, M.c. Chaparro-mercado, Bryan BilyeuAbstract:Residue of Allspice (Pimenta dioica L. Merrill) obtained as a by-product from the essential oil supercritical extraction process, has been evaluated as a biosorbent for removing lead (II) from aqueous solutions in batch studies, but not in a practical system like a fixed bed column [12,13]. In this paper, the effects of flow rate (20 and 40 mL/min), bed depth (8 and 15 cm) and influent lead concentration (15 and 25 mg/L) on the adsorption capacity of the residue of Allspice in a fixed-bed column were investigated. The highest adsorption capacity (99.2%) on a 15 mg/L Pb(II) solution was achieved within a flow rate of 20 mL/min and a bed depth of 15 cm. The experimental data obtained from the adsorption process was successfully correlated with the Thomas, Adams–Bohart, Yoon–Nelson, Bed Depth Service Time (BDST), and Dose Response models. A rigorous model based on the differential balance mass transfer was also used to describe the adsorption process in the column. The results of the parameters zone mass transfer, diffusion and mass transfer coefficients obtained with modeling the continuous process could be applied to scale up the process to an actual industrial column.
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Thermodynamical and analytical evidence of lead ions chemisorption onto Pimenta dioica
Chemical Engineering Journal, 2011Co-Authors: J Cruz-olivares, Carlos Barrera-díaz, C Pérez-alonso, Reyna Natividad, M.c. Chaparro-mercadoAbstract:Abstract Residue of Allspice ( Pimenta dioica L. Merrill) obtained as a by-product from the hydro-distillation oil process, has been studied as a low cost biosorbent for removing lead (II) ion from water solution at different temperatures. Batch experiments were performed with aqueous lead solutions of concentration 25 mg L −1 , at pH 5 and adsorbent dosage 1.0 g biosorbent per liter of solution. According to pseudo-second order kinetic model, the maximum adsorption capacity was 22.37 mg g −1 of Pb (II) on residue of Allspice (RA). This value was reached at 90 min and temperature of 308 K. Langmuir, Freundlich and Dubinin–Radushkevich (D–R) adsorption isotherm models were applied as an attempt to mathematically represent adsorption data. These three equations were found to be applicable to this adsorption system, in terms of relatively high regression values. Thermodynamic parameters showed that the adsorption of lead (II) onto RA was feasible, spontaneous, and endothermic under the studied conditions. The elemental analysis from scanning electron microscopy (SEM) before and after the contact showed that lead was adsorbed by RA. Diffusion results, the value of the free energy E (kJ mol −1 ), XPS and FTIR analysis confirmed that the lead (II) adsorption process onto RA was controlled by chemisorption.
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MOISTURE DIFFUSION IN Allspice (PIMENTA DIOICA L. MERRIL) FRUITS DURING FLUIDIZED BED DRYING
Journal of Food Processing and Preservation, 2010Co-Authors: C Pérez-alonso, J Cruz-olivares, A. Ramírez, Angélica Román-guerrero, Eduardo J. Vernon-carterAbstract:Allspice fruits (Pimenta dioica L. Merril) were dried in a laboratory fluidized bed dryer at three different inlet air temperatures (60, 70 and 80C), three different initial bed mass loads (0.300, 0.450 and 0.600 kg) and an air velocity of 3.4 m/s. The mean effective diffusion coefficients were obtained by analyzing the drying curves with Fick’s second law diffusional model for a spherical geometry, and ranged from 1.37 ¥ 10 -10 to 4.66 ¥ 10 -10 m 2 /s for moisture contents between 0.072 and 2.000 kg water/kg dry solids. An Arrhenius-type relationship was used for estimating the activation energy (Ea) required for moisture diffusion at a given temperature. The values for Ea were nonsignificantly different (55.78‐59.89 kJ/mol) for the different initial bed mass loads. Fick’s model describes successfully the Allspice drying process.
J Cruz-olivares - One of the best experts on this subject based on the ideXlab platform.
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Supercritical Extraction Process of Allspice Essential Oil
Journal of Chemistry, 2017Co-Authors: Yasvet Y. Andrade-avila, J Cruz-olivares, C Pérez-alonso, Ciro Humberto Ortiz-estrada, M.c. Chaparro-mercadoAbstract:Allspice essential oil was extracted with supercritical carbon dioxide (SC-CO2) in a static process at three different temperatures (308.15, 313.15, and 318.15 K) and four levels of pressure (100, 200, 300, and 360 bar). The amount of oil extracted was measured at intervals of 1, 2, 3, 4, 5, and 6 h; the most extraction yield reached was of 68.47% at 318.15 K, 360 bar, and 6 h of contact time. In this supercritical extraction process, the distribution coefficient ( ), the mean effective diffusion coefficient ( ), the energy of activation ( ), the thermodynamic properties ( , , and ), and the apparent solubility ( ) expressed as mass fraction (w/w) were evaluated for the first time. At the equilibrium the experimental apparent solubility data were successfully correlated with the modified Chrastil equation.
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Modeling of lead (II) biosorption by residue of Allspice in a fixed-bed column
Chemical Engineering Journal, 2013Co-Authors: J Cruz-olivares, Carlos Barrera-díaz, Fernando Ureña-núñez, C Pérez-alonso, M.c. Chaparro-mercado, Bryan BilyeuAbstract:Residue of Allspice (Pimenta dioica L. Merrill) obtained as a by-product from the essential oil supercritical extraction process, has been evaluated as a biosorbent for removing lead (II) from aqueous solutions in batch studies, but not in a practical system like a fixed bed column [12,13]. In this paper, the effects of flow rate (20 and 40 mL/min), bed depth (8 and 15 cm) and influent lead concentration (15 and 25 mg/L) on the adsorption capacity of the residue of Allspice in a fixed-bed column were investigated. The highest adsorption capacity (99.2%) on a 15 mg/L Pb(II) solution was achieved within a flow rate of 20 mL/min and a bed depth of 15 cm. The experimental data obtained from the adsorption process was successfully correlated with the Thomas, Adams–Bohart, Yoon–Nelson, Bed Depth Service Time (BDST), and Dose Response models. A rigorous model based on the differential balance mass transfer was also used to describe the adsorption process in the column. The results of the parameters zone mass transfer, diffusion and mass transfer coefficients obtained with modeling the continuous process could be applied to scale up the process to an actual industrial column.
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Thermodynamical and analytical evidence of lead ions chemisorption onto Pimenta dioica
Chemical Engineering Journal, 2011Co-Authors: J Cruz-olivares, Carlos Barrera-díaz, C Pérez-alonso, Reyna Natividad, M.c. Chaparro-mercadoAbstract:Abstract Residue of Allspice ( Pimenta dioica L. Merrill) obtained as a by-product from the hydro-distillation oil process, has been studied as a low cost biosorbent for removing lead (II) ion from water solution at different temperatures. Batch experiments were performed with aqueous lead solutions of concentration 25 mg L −1 , at pH 5 and adsorbent dosage 1.0 g biosorbent per liter of solution. According to pseudo-second order kinetic model, the maximum adsorption capacity was 22.37 mg g −1 of Pb (II) on residue of Allspice (RA). This value was reached at 90 min and temperature of 308 K. Langmuir, Freundlich and Dubinin–Radushkevich (D–R) adsorption isotherm models were applied as an attempt to mathematically represent adsorption data. These three equations were found to be applicable to this adsorption system, in terms of relatively high regression values. Thermodynamic parameters showed that the adsorption of lead (II) onto RA was feasible, spontaneous, and endothermic under the studied conditions. The elemental analysis from scanning electron microscopy (SEM) before and after the contact showed that lead was adsorbed by RA. Diffusion results, the value of the free energy E (kJ mol −1 ), XPS and FTIR analysis confirmed that the lead (II) adsorption process onto RA was controlled by chemisorption.
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MOISTURE DIFFUSION IN Allspice (PIMENTA DIOICA L. MERRIL) FRUITS DURING FLUIDIZED BED DRYING
Journal of Food Processing and Preservation, 2010Co-Authors: C Pérez-alonso, J Cruz-olivares, A. Ramírez, Angélica Román-guerrero, Eduardo J. Vernon-carterAbstract:Allspice fruits (Pimenta dioica L. Merril) were dried in a laboratory fluidized bed dryer at three different inlet air temperatures (60, 70 and 80C), three different initial bed mass loads (0.300, 0.450 and 0.600 kg) and an air velocity of 3.4 m/s. The mean effective diffusion coefficients were obtained by analyzing the drying curves with Fick’s second law diffusional model for a spherical geometry, and ranged from 1.37 ¥ 10 -10 to 4.66 ¥ 10 -10 m 2 /s for moisture contents between 0.072 and 2.000 kg water/kg dry solids. An Arrhenius-type relationship was used for estimating the activation energy (Ea) required for moisture diffusion at a given temperature. The values for Ea were nonsignificantly different (55.78‐59.89 kJ/mol) for the different initial bed mass loads. Fick’s model describes successfully the Allspice drying process.
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Inside the removal of lead(II) from aqueous solutions by De-Oiled Allspice Husk in batch and continuous processes.
Journal of hazardous materials, 2010Co-Authors: J Cruz-olivares, C Pérez-alonso, C Barrera-díaz, G López, P Balderas-hernándezAbstract:A new adsorbent material for removing lead ions from aqueous solutions has been investigated. The residue of the Allspice extraction process (De-Oiled Allspice Husk) was used on the removal of Pb(II) from water solutions. The lead sorption capacity of De-Olied Allspice Husk (DOAH) was studied in batch and continuous processes. It was found that percentage removals of Pb(II) depend on the pH and the initial lead concentrations. The Pb(II) uptake process was maximum at pH 5 in a range concentrations of 5-25 mg L(-1). The overall sorption process was well described by the pseudo-second-order kinetic model under conditions of pH 5 (0.1 g adsorbent per 100 mL of contaminated solution) 0.001 mass/volume ratio and 25 degrees C. The sorption capacity of lead(II) onto DOAH in batch process was 5.00, 8.02, 11.59, 15.23 and 20.07 mg g(-1), when the concentration solutions were 5, 10, 15, 20 and 25 mg L(-1) respectively. These values are lower than obtained in continuous process, where lead was removed by 95% and the experimental results were appropriately fitted by the Yoon-Nelson model. X-ray photoelectron spectroscopy (XPS) provides information regarding the interactions between lead ions and the adsorbent surface indicating that the formation of 2 complexes depends on the functional groups associated.
Tomáš Kuchta - One of the best experts on this subject based on the ideXlab platform.
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Improvement of the Detection Sensitivity for Staphylococcus aureus in Spices and Herbs
Food Analytical Methods, 2016Co-Authors: Tereza Cabicarová, Eva Kaclíková, Anneluise Mader, Jana Minarovičová, Janka Koreňová, Tomáš KuchtaAbstract:Various variants of ISO 6888-1:1999 and ISO 6888-3:2003 methods for the detection of Staphylococcus aureus were evaluated and improved for their application to conduct analysis in spices and herbs. Improvement substantiated in washing of the sample to remove compounds interfering with the analysis and in the use of PCR for final detection, instead of plating on Baird-Parker agar, to improve sensitivity at high backgrounds and to save time. The evaluation of the method variants was based on determination of the detection limit (LOD) using series of artificially contaminated spices (Allspice, black pepper, cinnamon, nutmeg, paprika, vanilla) and herbs (basil, oregano, parsley, thyme). The method without enrichment, ISO 6888-1:1999, produced LODs of 10^3–10^5 CFU/g with no positive effect of washing the sample or use of PCR for final detection. The method with enrichment, ISO 6888-3:2003, had LOD of 10^0 CFU/g for basil, black pepper, paprika and parsley. If the washing step was added and PCR was used for final detection, LOD of 10^0 CFU/g was determined also for cinnamon, nutmeg and vanilla, and LOD of 10^1 CFU/g was determined for Allspice. For oregano and thyme, which strongly inhibit the growth of S. aureus , an alternative enrichment-independent method based on direct DNA extraction coupled to real-time PCR may be advantageous.
