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Helena Maria André Bolini - One of the best experts on this subject based on the ideXlab platform.
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sensory profile and acceptability for pitanga eugenia uniflora l nectar with different sweeteners
Food Science and Technology International, 2016Co-Authors: Mirian Luisa Faria Freitas, Mariana Borges De Lima Dutra, Helena Maria André BoliniAbstract:The objective of this study was to evaluate the sensory properties and acceptability of pitanga nectar samples prepared with sucrose and different sweeteners (sucralose, aspartame, stevia with 40% rebaudioside A, stevia with 95% rebaudioside A, Neotame, and a 2:1 cyclamate/saccharin blend). A total of 13 assessors participated in a quantitative descriptive analysis and evaluated the samples in relation to the descriptor terms. The acceptability test was carried out by 120 fruit juice consumers. The results of the quantitative descriptive analysis of pitanga nectar showed that samples prepared with sucralose, aspartame, and the 2:1 cyclamate/saccharin blend had sensory profiles similar to that of the sample prepared with sucrose. Consumers' most accepted samples were prepared with sucrose, sucralose, aspartame, and Neotame. The sweeteners that have the greatest potential to replace sucrose in pitanga nectar are sucralose and aspartame.
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Chocolate Milk with Chia Oil: Ideal Sweetness, Sweeteners Equivalence, and Dynamic Sensory Evaluation Using a Time-Intensity Methodology.
Journal of Food Science, 2015Co-Authors: J.b. Rodrigues, J.a. Paixão, Adriano G. Cruz, Helena Maria André BoliniAbstract:The ideal sucrose concentration and equivalent concentrations of the stevia, sucralose, aspartame, and Neotame in chocolate milk with chia oil as well as the dynamic behavior of certain sensory attributes were investigated using a time-intensity methodology. The use of just-about-right (JAR) identified an ideal sucrose concentration of 9% (w/w). In addition, the magnitude estimation method showed that stevia had the lowest sweetness power whereas Neotame presented the highest. Furthermore, the time-intensity analysis indicated that there was no significant change between the maximum intensities of the sweetness for any evaluated sweeteners. In general, the desired sensory profile and some economic considerations are decisive on the choice of which sweetener is better to be used in chocolate milk formulation added with chia oil. Practical Application Chia seeds are considered as one of the highest sources of omega-3 fatty acids among plants. The possibility of developing a functional chocolate milk rich in omega-3, associated with a formulation with sweetener to reduce calories, is quite interesting and promising in the functional food sector. Chocolate milk had a great commercialization, however, must ensure that the used sweeteners have the same power of sweetness of sucrose in order to ensure consumer acceptability.
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Different sweeteners in passion fruit juice: Ideal and equivalent sweetness
Lwt - Food Science and Technology, 2015Co-Authors: Izabela Furtado De Oliveira Rocha, Helena Maria André BoliniAbstract:The aim of this study was to determine the ideal equivalence of sweetness (equi-sweetness) and acceptance of passion fruit juice sweetened with sucrose and different sweeteners. The ideal sweetness of the samples sweetened with sucrose at 5.0, 7.5, 10.0, 12.5, and 15.0 g/100 g, were analyzed using an acceptance test with a just-about-right (JAR) scale and 60 consumers of tropical fruits juices. The magnitude estimation method was used to determine the equi-sweetness of the six different sweeteners. Six samples containing different sweeteners were prepared as follows: sucrose, aspartame, cyclamate/saccharin blend 2:1, stevia, sucralose and Neotame. All samples were prepared to be equi-sweet, and the overall liking was determined using a 9-cm linear hedonic scale. Analysis of variance (ANOVA), Tukey's test and Internal Preference Mapping multivariate statistical analysis were applied using SAS software. The ideal sweetness analysis revealed that 9.4 g/100 g was the ideal sucrose concentration. The relative sweetness analysis showed that Neotame presented the highest sweetening power, being 6025.64 times sweeter than sucrose in relation to passion fruit juice containing 9.4 g/100 g of sucrose, followed by sucralose (590.02), cyclamate/saccharin blend 2:1 (262.28), aspartame (171.62), and stevia (94.72). The acceptance test of the present study confirmed aspartame and sucralose as the best sucrose substitutes when compared with other sweeteners.
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High‐intensity sweeteners in espresso coffee: ideal and equivalent sweetness and time–intensity analysis
International Journal of Food Science and Technology, 2015Co-Authors: Bruna Marcacini Azevedo, Flávio Luis Schmidt, Helena Maria André BoliniAbstract:Summary The efficient substitution of sucrose by a sweetener in beverages requires the application of some sensory techniques. First, one must determine the concentrations of the sweeteners under study, equivalent in sweetness to the ideal sucrose concentration. In addition, it is fundamental to determine which is most similar to sucrose. The objectives of this study were to determine the ideal sweetness for espresso coffee and the equivalent concentrations in sweetness of different sweeteners, as well as characterise the time–intensity profile of each sweetener in relation to sweetness. The sweeteners evaluated were sucralose, aspartame, Neotame, a cyclamate/saccharin mixture (2:1) and stevia. The sucrose concentration considered ideal by consumers was 12.5% (w/v), and the equivalent concentrations of the sweeteners were 0.0159% for sucralose, 0.0549% for aspartame, 0.0016% for Neotame, 0.0359% for the cyclamate/saccharin mixture and 0.0998% for stevia. The time–intensity analysis indicated that possibly the sweeteners Neotame, aspartame and sucralose would be the best substitutes for sucrose.
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MULTIPLE TIME-INTENSITY ANALYSIS AND TEMPORAL DOMINANCE OF SENSATIONS OF CHOCOLATE DAIRY DESSERT USING PREBIOTIC AND DIFFERENT HIGH-INTENSITY SWEETENERS
Journal of Sensory Studies, 2014Co-Authors: E. C. Morais, A.c.m. Pinheiro, C. A. Nunes, Helena Maria André BoliniAbstract:This paper presents a novel concept for producing chocolate dairy desserts using prebiotic and sucrose substitutes. The quality of chocolate dairy desserts was analyzed by the multiple time-intensity analysis and temporal dominance of sensations (TDS). Time-intensity analysis showed that the sample developed with Neotame had a higher intensity of sweetness; the samples with Neotame and stevia had a higher intensity of bitterness; and the samples with sucrose, sucralose, aspartame and the integral one had a higher intensity of chocolate flavor. Sucralose and aspartame provided a temporal profile with parameter curves closer to the one sweetened with sucrose, as well as the addition of prebiotics. The TDS analysis also showed a similar profile between the integral sample and the prebiotic light samples with sucralose and aspartame, in relation to the attributes of sweetness, bitterness, milk chocolate flavor, bittersweet chocolate flavor, milk powder, cream and off-flavor. In this context, the addition of prebiotic and replacement of sucrose by sweeteners opens up new opportunities in product development, especially in chocolate formulation for dietetic and functional purposes. Practical Applications Temporal dominance of sensations (TDS) has led to improve a better understanding of temporality behavior of dairy desserts' taste and flavor. In this study, the time-intensity analysis allowed the verification of changes in the perception of a product's attribute over time while TDS provided how the flavor behavior is for consumers during the dairy dessert ingestion and obtained the temporal profile of all attributes related to flavor. These methodologies are complementary and they are very useful for dairy dessert processors and people who work in the functional and sweetener industry.
Indra Prakash - One of the best experts on this subject based on the ideXlab platform.
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Development of rebiana, a natural, non-caloric sweetener
Food and Chemical Toxicology, 2008Co-Authors: Indra Prakash, Grant E. Dubois, John F. Clos, K.l. Wilkens, L.e. FosdickAbstract:Abstract Rebiana is the common name for high-purity rebaudioside A, a natural non-calorie sweetener 200–300 times more potent than sucrose. It provides zero calories and has a clean, sweet taste with no significant undesirable taste characteristics. It is functional in a wide array of beverages and foods and can be blended with other non-calorie or carbohydrate sweeteners. It is stable under dry conditions, and has much better stability than aspartame or Neotame in aqueous food systems. Studies undertaken for the development of a purification process and for the full characterization of the properties of rebiana are reported here.
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development of a new no calorie commercial sweetener Neotame
ACS symposium series, 2008Co-Authors: Indra Prakash, Ihab E BishayAbstract:Neotame, a new high potency sweetener and flavor enhancer, is derived from aspartame and is 8000 times sweeter than sucrose. It provides zero calories and has clean, sweet sugar-like taste with no undesirable taste characteristics. It is functional in a wide array of beverages and foods and can be used with other high potency or carbohydrate sweeteners. It is stable under dry conditions, and has comparable stability to aspartame in aqueous food systems. It is safe for use by general population and has been approved by U. S. FDA and several other countries around the world. Development of Neotame i.e. discovery, manufacture, physical and chemical characteristics, taste profile, blends, stability and applications will be reviewed.
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quantitation of crystalline and amorphous forms of anhydrous Neotame using 13c cpmas nmr spectroscopy
Journal of Pharmaceutical Sciences, 2005Co-Authors: Thomas J Offerdahl, Zedong Dong, Indra Prakash, David J W Grant, Jonathon S Salsbury, Stephen A Schroeder, Eric M Gorman, Dewey H Barich, Eric J MunsonAbstract:ABSTRACT: Although most drugs are formulated in the crystalline state, amorphous or other crystalline forms are often generated during the formulation process. The presence of other forms can dramatically affect the physical and chemical stability of the drug. The identification and quantitation of different forms of a drug is a significant analytical challenge, especially in a formulated product. The ability of solid-state 13 C NMR spectroscopy with cross polarization (CP) and magic-angle spinning (MAS) to quantify the amounts of three of the multiple crystalline and amorphous forms of the artificial sweetener Neotame is described. It was possible to quantify, in a mixture of two anhydrous polymorphic forms of Neotame, the amount of each polymorph within 1–2%. In mixtures of amorphous and crystalline forms of Neotame, the amorphous content could be determined within 5%. It was found that the crystalline standards that were used to prepare the mixtures were not pure crystalline forms, but rather a mixture of crystalline and amorphous forms. The effect of amorphous content in the crystalline standards on the overall quantitation of the two crystalline polymorphic forms is discussed. The importance of differences in relaxation parameters and CP efficiencies on quantifying mixtures of different forms using solid-state NMR spectroscopy is also addressed. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association.
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Crystal structure and physical characterization of N-(3,3-dimethylbutyl)-l-α-aspartyl-l-phenylalanine, the hydrolysis product of Neotame
Journal of Chemical Crystallography, 2005Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, William W. Brennessel, Brian E. Padden, Ihab Bishay, David J W GrantAbstract:The hydrolysis product of Neotame, N -(3,3-dimethylbutyl)- l -α-aspartyl- l -phenylalanine (DMBAP), was crystallized from water as an anhydrate with a melting point at 197○C with decomposition. Its crystal structure was determined by single crystal X-ray diffractometry. The crystal is orthorhombic with space group P 2_12__12_1 with Z =4 and one molecule per asymmetric unit. The cell constants are a =5.520 (2) Å, $b=10.608$ (5) Å and c = 31.92 (2) Å. The ^13C solid-state nuclear magnetic resonance spectrum of DMBAP is compared with those of Neotame monohydrate and Neotame methanol solvate.
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Crystal structures of the benzene and ethanol solvates of Neotame
Journal of Chemical Crystallography, 2003Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, David J W GrantAbstract:The benzene and ethanol solvates of Neotame crystallized from solutions of Neotame anhydrate in benzene and ethanol, respectively. The crystal structures of the two solvates were determined by single-crystal X-ray diffraction using synchrotron radiation. The benzene solvate crystallizes in the monoclinic space group, P 2_1, Z = 2, with one Neotame molecule and one benzene molecule per asymmetric unit. The cell constants are a = 13.060 (6) Å, b = 5.582 (2) Å, c = 17.954 (9) Å, and β = 102.079 (15)°. The ethanol solvate crystallizes in the orthorhombic space group, P 2_12_12_1 with Z = 8 ( Z ′ = 2). The cell constants are a = 10.047 (4) Å, b = 17.001 (4) Å, and c = 28.948 (7) Å. Intermolecular hydrogen bonding among Neotame molecules is evident in the two crystals. The benzene solvate has a nonpolar region containing the benzene molecules, with the benzene rings and alkyl chains of the Neotame molecules.
David J W Grant - One of the best experts on this subject based on the ideXlab platform.
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quantitation of crystalline and amorphous forms of anhydrous Neotame using 13c cpmas nmr spectroscopy
Journal of Pharmaceutical Sciences, 2005Co-Authors: Thomas J Offerdahl, Zedong Dong, Indra Prakash, David J W Grant, Jonathon S Salsbury, Stephen A Schroeder, Eric M Gorman, Dewey H Barich, Eric J MunsonAbstract:ABSTRACT: Although most drugs are formulated in the crystalline state, amorphous or other crystalline forms are often generated during the formulation process. The presence of other forms can dramatically affect the physical and chemical stability of the drug. The identification and quantitation of different forms of a drug is a significant analytical challenge, especially in a formulated product. The ability of solid-state 13 C NMR spectroscopy with cross polarization (CP) and magic-angle spinning (MAS) to quantify the amounts of three of the multiple crystalline and amorphous forms of the artificial sweetener Neotame is described. It was possible to quantify, in a mixture of two anhydrous polymorphic forms of Neotame, the amount of each polymorph within 1–2%. In mixtures of amorphous and crystalline forms of Neotame, the amorphous content could be determined within 5%. It was found that the crystalline standards that were used to prepare the mixtures were not pure crystalline forms, but rather a mixture of crystalline and amorphous forms. The effect of amorphous content in the crystalline standards on the overall quantitation of the two crystalline polymorphic forms is discussed. The importance of differences in relaxation parameters and CP efficiencies on quantifying mixtures of different forms using solid-state NMR spectroscopy is also addressed. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association.
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Crystal structure and physical characterization of N-(3,3-dimethylbutyl)-l-α-aspartyl-l-phenylalanine, the hydrolysis product of Neotame
Journal of Chemical Crystallography, 2005Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, William W. Brennessel, Brian E. Padden, Ihab Bishay, David J W GrantAbstract:The hydrolysis product of Neotame, N -(3,3-dimethylbutyl)- l -α-aspartyl- l -phenylalanine (DMBAP), was crystallized from water as an anhydrate with a melting point at 197○C with decomposition. Its crystal structure was determined by single crystal X-ray diffractometry. The crystal is orthorhombic with space group P 2_12__12_1 with Z =4 and one molecule per asymmetric unit. The cell constants are a =5.520 (2) Å, $b=10.608$ (5) Å and c = 31.92 (2) Å. The ^13C solid-state nuclear magnetic resonance spectrum of DMBAP is compared with those of Neotame monohydrate and Neotame methanol solvate.
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Crystal structures of the benzene and ethanol solvates of Neotame
Journal of Chemical Crystallography, 2003Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, David J W GrantAbstract:The benzene and ethanol solvates of Neotame crystallized from solutions of Neotame anhydrate in benzene and ethanol, respectively. The crystal structures of the two solvates were determined by single-crystal X-ray diffraction using synchrotron radiation. The benzene solvate crystallizes in the monoclinic space group, P 2_1, Z = 2, with one Neotame molecule and one benzene molecule per asymmetric unit. The cell constants are a = 13.060 (6) Å, b = 5.582 (2) Å, c = 17.954 (9) Å, and β = 102.079 (15)°. The ethanol solvate crystallizes in the orthorhombic space group, P 2_12_12_1 with Z = 8 ( Z ′ = 2). The cell constants are a = 10.047 (4) Å, b = 17.001 (4) Å, and c = 28.948 (7) Å. Intermolecular hydrogen bonding among Neotame molecules is evident in the two crystals. The benzene solvate has a nonpolar region containing the benzene molecules, with the benzene rings and alkyl chains of the Neotame molecules.
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Crystal Structure of Neotame Anhydrate Polymorph G
Pharmaceutical Research, 2002Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, Agam Sheth, David J W GrantAbstract:Purpose . To determine the crystal structure of the Neotame anhydrate polymorph G and to evaluate X-ray powder diffractometry (XRPD) with molecular modeling as an alternative method for determining the crystal structure of this conformationally flexible dipeptide. Methods . The crystal structure of polymorph G was determined by single crystal X-ray crystallography (SCXRD) and also from the X-ray powder diffraction (XRPD) pattern using molecular modeling (Cerius^2 ™, Powder Solve module). Results . From SCXRD, polymorph G crystals are orthorhombic with space group of P 2_12_12_1 with Z = 4, unit cell constants: a = 5.5999(4), b = 11.8921(8), c = 30.917(2) Å, and one Neotame molecule per asymmetric unit. The XRPD pattern of polymorph G, analyzed by Cerius^2 ™ software, led to the same P 2_12_12_1 space group and almost identical unit cell dimensions. However, with 13 rigid bodies defined, Cerius^2 ™ gives a conformation of the Neotame molecule, which is different from that determined by SCXRD. Conclusions . For Neotame anhydrate polymorph G, the unit cell dimensions calculated from XRPD were almost identical to those determined by SCXRD. However, the crystal structure determined by XRPD closely resembled that determined by SCXRD, only when the correct conformation of the Neotame molecule had been chosen before detailed analysis of the XRPD pattern.
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conformational flexibility and hydrogen bonding patterns of the Neotame molecule in its various solid forms
Journal of Pharmaceutical Sciences, 2002Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, David J W GrantAbstract:Abstract The conformational flexibility and the molecular packing patterns of the Neotame molecule in its various crystal forms, including Neotame monohydrate, methanol solvate, ethanol solvate, benzene solvate, and anhydrate polymorph G, are analyzed in this work. The Cerius 2, ™ molecular modeling program with the Dreiding 2.21 force field was employed to calculate the most stable conformations of Neotame molecules in the gaseous state and to analyze the conformations of the Neotame molecule in its various crystal forms. Using graph set analysis, the hydrogen bond patterns of these crystal forms were compared. The Neotame molecule takes different conformations in its crystal forms and in the free gaseous state. Cerius 2, ™ found 10 conformers with lower conformational energies than those in the actual crystal structures, which represent an energetic compromise. The relatively large differences between the energies of the conformers indicate the necessity for rewriting or customizing the force field for Neotame. The hydrogen bonding patterns of the Neotame methanol and ethanol solvates are identical, but different from those of the other three forms, which also differ from each other. The Neotame molecule in its various crystal forms takes different conformations that differ from those in the gaseous state because of the influence of crystal packing. The intramolecular ring, S (5), is present in all the crystal forms. The following hydrogen bonding patterns occur in some of the crystal forms: diad, D ; intramolecular rings, S (6) and S (7); chains, C (5) and C (6); and an intermolecular ring, R 2 2 ( 12 ) . © 2002 Wiley‐Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:2047–2056, 2002
Eric J Munson - One of the best experts on this subject based on the ideXlab platform.
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quantitation of crystalline and amorphous forms of anhydrous Neotame using 13c cpmas nmr spectroscopy
Journal of Pharmaceutical Sciences, 2005Co-Authors: Thomas J Offerdahl, Zedong Dong, Indra Prakash, David J W Grant, Jonathon S Salsbury, Stephen A Schroeder, Eric M Gorman, Dewey H Barich, Eric J MunsonAbstract:ABSTRACT: Although most drugs are formulated in the crystalline state, amorphous or other crystalline forms are often generated during the formulation process. The presence of other forms can dramatically affect the physical and chemical stability of the drug. The identification and quantitation of different forms of a drug is a significant analytical challenge, especially in a formulated product. The ability of solid-state 13 C NMR spectroscopy with cross polarization (CP) and magic-angle spinning (MAS) to quantify the amounts of three of the multiple crystalline and amorphous forms of the artificial sweetener Neotame is described. It was possible to quantify, in a mixture of two anhydrous polymorphic forms of Neotame, the amount of each polymorph within 1–2%. In mixtures of amorphous and crystalline forms of Neotame, the amorphous content could be determined within 5%. It was found that the crystalline standards that were used to prepare the mixtures were not pure crystalline forms, but rather a mixture of crystalline and amorphous forms. The effect of amorphous content in the crystalline standards on the overall quantitation of the two crystalline polymorphic forms is discussed. The importance of differences in relaxation parameters and CP efficiencies on quantifying mixtures of different forms using solid-state NMR spectroscopy is also addressed. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association.
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Crystal structure and physical characterization of N-(3,3-dimethylbutyl)-l-α-aspartyl-l-phenylalanine, the hydrolysis product of Neotame
Journal of Chemical Crystallography, 2005Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, William W. Brennessel, Brian E. Padden, Ihab Bishay, David J W GrantAbstract:The hydrolysis product of Neotame, N -(3,3-dimethylbutyl)- l -α-aspartyl- l -phenylalanine (DMBAP), was crystallized from water as an anhydrate with a melting point at 197○C with decomposition. Its crystal structure was determined by single crystal X-ray diffractometry. The crystal is orthorhombic with space group P 2_12__12_1 with Z =4 and one molecule per asymmetric unit. The cell constants are a =5.520 (2) Å, $b=10.608$ (5) Å and c = 31.92 (2) Å. The ^13C solid-state nuclear magnetic resonance spectrum of DMBAP is compared with those of Neotame monohydrate and Neotame methanol solvate.
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Crystal structures of the benzene and ethanol solvates of Neotame
Journal of Chemical Crystallography, 2003Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, David J W GrantAbstract:The benzene and ethanol solvates of Neotame crystallized from solutions of Neotame anhydrate in benzene and ethanol, respectively. The crystal structures of the two solvates were determined by single-crystal X-ray diffraction using synchrotron radiation. The benzene solvate crystallizes in the monoclinic space group, P 2_1, Z = 2, with one Neotame molecule and one benzene molecule per asymmetric unit. The cell constants are a = 13.060 (6) Å, b = 5.582 (2) Å, c = 17.954 (9) Å, and β = 102.079 (15)°. The ethanol solvate crystallizes in the orthorhombic space group, P 2_12_12_1 with Z = 8 ( Z ′ = 2). The cell constants are a = 10.047 (4) Å, b = 17.001 (4) Å, and c = 28.948 (7) Å. Intermolecular hydrogen bonding among Neotame molecules is evident in the two crystals. The benzene solvate has a nonpolar region containing the benzene molecules, with the benzene rings and alkyl chains of the Neotame molecules.
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Crystal Structure of Neotame Anhydrate Polymorph G
Pharmaceutical Research, 2002Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, Agam Sheth, David J W GrantAbstract:Purpose . To determine the crystal structure of the Neotame anhydrate polymorph G and to evaluate X-ray powder diffractometry (XRPD) with molecular modeling as an alternative method for determining the crystal structure of this conformationally flexible dipeptide. Methods . The crystal structure of polymorph G was determined by single crystal X-ray crystallography (SCXRD) and also from the X-ray powder diffraction (XRPD) pattern using molecular modeling (Cerius^2 ™, Powder Solve module). Results . From SCXRD, polymorph G crystals are orthorhombic with space group of P 2_12_12_1 with Z = 4, unit cell constants: a = 5.5999(4), b = 11.8921(8), c = 30.917(2) Å, and one Neotame molecule per asymmetric unit. The XRPD pattern of polymorph G, analyzed by Cerius^2 ™ software, led to the same P 2_12_12_1 space group and almost identical unit cell dimensions. However, with 13 rigid bodies defined, Cerius^2 ™ gives a conformation of the Neotame molecule, which is different from that determined by SCXRD. Conclusions . For Neotame anhydrate polymorph G, the unit cell dimensions calculated from XRPD were almost identical to those determined by SCXRD. However, the crystal structure determined by XRPD closely resembled that determined by SCXRD, only when the correct conformation of the Neotame molecule had been chosen before detailed analysis of the XRPD pattern.
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conformational flexibility and hydrogen bonding patterns of the Neotame molecule in its various solid forms
Journal of Pharmaceutical Sciences, 2002Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, David J W GrantAbstract:Abstract The conformational flexibility and the molecular packing patterns of the Neotame molecule in its various crystal forms, including Neotame monohydrate, methanol solvate, ethanol solvate, benzene solvate, and anhydrate polymorph G, are analyzed in this work. The Cerius 2, ™ molecular modeling program with the Dreiding 2.21 force field was employed to calculate the most stable conformations of Neotame molecules in the gaseous state and to analyze the conformations of the Neotame molecule in its various crystal forms. Using graph set analysis, the hydrogen bond patterns of these crystal forms were compared. The Neotame molecule takes different conformations in its crystal forms and in the free gaseous state. Cerius 2, ™ found 10 conformers with lower conformational energies than those in the actual crystal structures, which represent an energetic compromise. The relatively large differences between the energies of the conformers indicate the necessity for rewriting or customizing the force field for Neotame. The hydrogen bonding patterns of the Neotame methanol and ethanol solvates are identical, but different from those of the other three forms, which also differ from each other. The Neotame molecule in its various crystal forms takes different conformations that differ from those in the gaseous state because of the influence of crystal packing. The intramolecular ring, S (5), is present in all the crystal forms. The following hydrogen bonding patterns occur in some of the crystal forms: diad, D ; intramolecular rings, S (6) and S (7); chains, C (5) and C (6); and an intermolecular ring, R 2 2 ( 12 ) . © 2002 Wiley‐Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:2047–2056, 2002
Zedong Dong - One of the best experts on this subject based on the ideXlab platform.
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quantitation of crystalline and amorphous forms of anhydrous Neotame using 13c cpmas nmr spectroscopy
Journal of Pharmaceutical Sciences, 2005Co-Authors: Thomas J Offerdahl, Zedong Dong, Indra Prakash, David J W Grant, Jonathon S Salsbury, Stephen A Schroeder, Eric M Gorman, Dewey H Barich, Eric J MunsonAbstract:ABSTRACT: Although most drugs are formulated in the crystalline state, amorphous or other crystalline forms are often generated during the formulation process. The presence of other forms can dramatically affect the physical and chemical stability of the drug. The identification and quantitation of different forms of a drug is a significant analytical challenge, especially in a formulated product. The ability of solid-state 13 C NMR spectroscopy with cross polarization (CP) and magic-angle spinning (MAS) to quantify the amounts of three of the multiple crystalline and amorphous forms of the artificial sweetener Neotame is described. It was possible to quantify, in a mixture of two anhydrous polymorphic forms of Neotame, the amount of each polymorph within 1–2%. In mixtures of amorphous and crystalline forms of Neotame, the amorphous content could be determined within 5%. It was found that the crystalline standards that were used to prepare the mixtures were not pure crystalline forms, but rather a mixture of crystalline and amorphous forms. The effect of amorphous content in the crystalline standards on the overall quantitation of the two crystalline polymorphic forms is discussed. The importance of differences in relaxation parameters and CP efficiencies on quantifying mixtures of different forms using solid-state NMR spectroscopy is also addressed. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association.
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Crystal structure and physical characterization of N-(3,3-dimethylbutyl)-l-α-aspartyl-l-phenylalanine, the hydrolysis product of Neotame
Journal of Chemical Crystallography, 2005Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, William W. Brennessel, Brian E. Padden, Ihab Bishay, David J W GrantAbstract:The hydrolysis product of Neotame, N -(3,3-dimethylbutyl)- l -α-aspartyl- l -phenylalanine (DMBAP), was crystallized from water as an anhydrate with a melting point at 197○C with decomposition. Its crystal structure was determined by single crystal X-ray diffractometry. The crystal is orthorhombic with space group P 2_12__12_1 with Z =4 and one molecule per asymmetric unit. The cell constants are a =5.520 (2) Å, $b=10.608$ (5) Å and c = 31.92 (2) Å. The ^13C solid-state nuclear magnetic resonance spectrum of DMBAP is compared with those of Neotame monohydrate and Neotame methanol solvate.
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Crystal structures of the benzene and ethanol solvates of Neotame
Journal of Chemical Crystallography, 2003Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, David J W GrantAbstract:The benzene and ethanol solvates of Neotame crystallized from solutions of Neotame anhydrate in benzene and ethanol, respectively. The crystal structures of the two solvates were determined by single-crystal X-ray diffraction using synchrotron radiation. The benzene solvate crystallizes in the monoclinic space group, P 2_1, Z = 2, with one Neotame molecule and one benzene molecule per asymmetric unit. The cell constants are a = 13.060 (6) Å, b = 5.582 (2) Å, c = 17.954 (9) Å, and β = 102.079 (15)°. The ethanol solvate crystallizes in the orthorhombic space group, P 2_12_12_1 with Z = 8 ( Z ′ = 2). The cell constants are a = 10.047 (4) Å, b = 17.001 (4) Å, and c = 28.948 (7) Å. Intermolecular hydrogen bonding among Neotame molecules is evident in the two crystals. The benzene solvate has a nonpolar region containing the benzene molecules, with the benzene rings and alkyl chains of the Neotame molecules.
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Crystal Structure of Neotame Anhydrate Polymorph G
Pharmaceutical Research, 2002Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, Victor G. Young, Agam Sheth, David J W GrantAbstract:Purpose . To determine the crystal structure of the Neotame anhydrate polymorph G and to evaluate X-ray powder diffractometry (XRPD) with molecular modeling as an alternative method for determining the crystal structure of this conformationally flexible dipeptide. Methods . The crystal structure of polymorph G was determined by single crystal X-ray crystallography (SCXRD) and also from the X-ray powder diffraction (XRPD) pattern using molecular modeling (Cerius^2 ™, Powder Solve module). Results . From SCXRD, polymorph G crystals are orthorhombic with space group of P 2_12_12_1 with Z = 4, unit cell constants: a = 5.5999(4), b = 11.8921(8), c = 30.917(2) Å, and one Neotame molecule per asymmetric unit. The XRPD pattern of polymorph G, analyzed by Cerius^2 ™ software, led to the same P 2_12_12_1 space group and almost identical unit cell dimensions. However, with 13 rigid bodies defined, Cerius^2 ™ gives a conformation of the Neotame molecule, which is different from that determined by SCXRD. Conclusions . For Neotame anhydrate polymorph G, the unit cell dimensions calculated from XRPD were almost identical to those determined by SCXRD. However, the crystal structure determined by XRPD closely resembled that determined by SCXRD, only when the correct conformation of the Neotame molecule had been chosen before detailed analysis of the XRPD pattern.
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conformational flexibility and hydrogen bonding patterns of the Neotame molecule in its various solid forms
Journal of Pharmaceutical Sciences, 2002Co-Authors: Zedong Dong, Eric J Munson, Steve A Schroeder, Indra Prakash, David J W GrantAbstract:Abstract The conformational flexibility and the molecular packing patterns of the Neotame molecule in its various crystal forms, including Neotame monohydrate, methanol solvate, ethanol solvate, benzene solvate, and anhydrate polymorph G, are analyzed in this work. The Cerius 2, ™ molecular modeling program with the Dreiding 2.21 force field was employed to calculate the most stable conformations of Neotame molecules in the gaseous state and to analyze the conformations of the Neotame molecule in its various crystal forms. Using graph set analysis, the hydrogen bond patterns of these crystal forms were compared. The Neotame molecule takes different conformations in its crystal forms and in the free gaseous state. Cerius 2, ™ found 10 conformers with lower conformational energies than those in the actual crystal structures, which represent an energetic compromise. The relatively large differences between the energies of the conformers indicate the necessity for rewriting or customizing the force field for Neotame. The hydrogen bonding patterns of the Neotame methanol and ethanol solvates are identical, but different from those of the other three forms, which also differ from each other. The Neotame molecule in its various crystal forms takes different conformations that differ from those in the gaseous state because of the influence of crystal packing. The intramolecular ring, S (5), is present in all the crystal forms. The following hydrogen bonding patterns occur in some of the crystal forms: diad, D ; intramolecular rings, S (6) and S (7); chains, C (5) and C (6); and an intermolecular ring, R 2 2 ( 12 ) . © 2002 Wiley‐Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:2047–2056, 2002
