ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTQuantitation of hexane-extractable lipids in serial samples of flue-cured tobaccosJames J. Ellington, Patricia F. Schlotzhauer, and Abner I. SchepartzCite this: J. Agric. Food Chem. 1978, 26, 1, 270–273Publication Date (Print):January 1, 1978Publication History Published online1 May 2002Published inissue 1 January 1978https://pubs.acs.org/doi/10.1021/jf60215a049https://doi.org/10.1021/jf60215a049research-articleACS PublicationsRequest reuse permissionsArticle Views61Altmetric-Citations10LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLipid distribution in flue-cured tobacco plantsJames J. Ellington, Patricia F. Schlotzhauer, and Abner I. SchepartzCite this: J. Agric. Food Chem. 1978, 26, 2, 407–410Publication Date (Print):March 1, 1978Publication History Published online1 May 2002Published inissue 1 March 1978https://pubs.acs.org/doi/10.1021/jf60216a012https://doi.org/10.1021/jf60216a012research-articleACS PublicationsRequest reuse permissionsArticle Views48Altmetric-Citations6LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

The hexane extractable fraction of tobacco is important because its lipid components affect leaf quality and are precursors of polynuclear aromatic hydrocarbons (PAH) in smoke (1,2). Swain et al. (3) reported a qualitative analysis of this fraction in 1961. However, 69% of the fraction was reported as resinous material and was not identified. Cook et al. (4) in 1968 fractionated a hexane extract according to polarity and molecular weight by utilizing counter-current distribution and gel permeation chromatography. These techniques permitted nondestructive, quantitative recovery of components for identification by various analytical methods. The molecular weights of 70% of the nonbasic compounds in the hexane extract were found to be below 800 daltons, suggesting the presence of relatively simple components. Most quantitative studies of the major tobacco lipids have been limited to individual compounds or classes of compounds. Thus, fatty acids and their esters (5–8), sterols and steryl esters (9–13), neophytadiene (14,15) hydrocarbon waxes (15,16) and solanesol (17,18), which constitute the major tobacco lipids, have been quantitated by various research groups. In most instances only one or two of these compounds or classes of compounds have been analyzed in the same tobacco sample.

Solanesol, a trisesquiterpenoid alcohol in tobacco leaf, has been shown to be an important precursor of the tumorigenic polynuclear aromatic hydrocarbons of smoke. Thus, a rapid, reproducible method for the determination of leaf solanesol levels is desirable. We developed procedures based on high-temperature gas chromatography for the analyses of free and total solanesol. The alcohol, as its trimethylsilyl derivative, was separated and quantified on a short Dexsil 300 GC column, with 1,3-dimyristin as an internal standard. The free alcohol was determined by direct derivatization of ground tobacco and its hexane extract with N,O-bis(trimethylsilyl)-acetamide-dimethylformamide reagents. For total solanesol, the ground tobacco or its hexane extract was saponified with ethanolic potassium hydroxide. Acidification and hexane extraction yielded samples suitable for silylation and gas chromatographic analysis. Evaluation of the various methods indicated that free solanesol was best determined in the hexane extract of tobacco, and total solanesol after saponification of ground tobacco. Total solanesol levels in commercially important tobacco types were determined.

ADVERTISEMENT RETURN TO ISSUEPREVArticleElectrophoretic detection of protein in highly pigmented tobaccoDavid G. Bailey and Abner I. SchepartzCite this: J. Agric. Food Chem. 1977, 25, 6, 1432–1434Publication Date (Print):November 1, 1977Publication History Published online1 May 2002Published inissue 1 November 1977https://pubs.acs.org/doi/10.1021/jf60214a029https://doi.org/10.1021/jf60214a029research-articleACS PublicationsRequest reuse permissionsArticle Views31Altmetric-Citations1LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Fatty acids obtained by saponification of a hexane-soluble fraction of flue-cured tobacco were converted to their methyl esters. The esters were purified by TLC and identified by GC-MS. Qualitative and quantitative results are reported for acids of chain lengths C12-C34.

During the usual air curing of cigar-filler tobacco the peroxidase activity decreases rapidly for 6 weeks and then becomes stabilized at a level approximately one-fifth the original. Detectable activity persists during storage for as long as 5 years. The presence of enzymatic activity demonstrates that protein is present in the fully cured and stored leaf.

The selectivity properties of Sephadex gels toward various metabolic phosphates (nucleotides and coenzymes) have been examined by column chromatography using distilled water as eluent. These compounds are grouped within a range of Kd values from 0.22 to 0.39 on Sephadex G-10. Sephadex G-15 differs from G-10 in possessing a greater affinity for phosphates. The Kd values are only slightly less clustered on this gel, and there is but a negligible increase in the range of partition coefficients. Chromatography on G-25, on the other hand, gives a relatively good spread of Kd values. Several compounds have partition coefficients greater than 1.00. Whereas phosphate affinity decreases with increasing gel density, riboflavin, a nonphosphorylated reference compound, has the highest affinity for G-10 of all substances tested.

Crospovidone is an insoluble form of polyvinylpyrrolidone, and its use in the pharmaceutical industry as a tablet excipient (a tablet disintegrant and binder) has been widely documented. It is medically used for the treatment of some intestinal disorders as solubilizing excipients to improve the bioavailability of drugs (such as steroids) and as germicides in wound treatment. It is also commonly used as a clarifier in alcoholic and nonalcoholic beverages. This chapter describes the methods of crospovidone preparation and discusses its physical properties and primary uses. The primary pharmaceutical application of crospovidone is that of a tablet disintegrant, although it can also function as a tablet binder. For a polymer to be useful as a pharmaceutical excipient, grades of material need to possess properties such as high swelling capacity, high capillary activity, high hydration capacity, and low bulk density. The chapter discusses the interactions of crospovidone with drug substances.

Crospovidone is an insoluble form of polyvinylpyrrolidone, and its use in the pharmaceutical industry as a tablet excipient (a tablet disintegrant and binder) has been widely documented. It is medically used for the treatment of some intestinal disorders as solubilizing excipients to improve the bioavailability of drugs (such as steroids) and as germicides in wound treatment. It is also commonly used as a clarifier in alcoholic and nonalcoholic beverages. This chapter describes the methods of crospovidone preparation and discusses its physical properties and primary uses. The primary pharmaceutical application of crospovidone is that of a tablet disintegrant, although it can also function as a tablet binder. For a polymer to be useful as a pharmaceutical excipient, grades of material need to possess properties such as high swelling capacity, high capillary activity, high hydration capacity, and low bulk density. The chapter discusses the interactions of crospovidone with drug substances.

Crospovidone is an insoluble form of polyvinylpyrrolidone, and its use in the pharmaceutical industry as a tablet excipient (a tablet disintegrant and binder) has been widely documented. It is medically used for the treatment of some intestinal disorders as solubilizing excipients to improve the bioavailability of drugs (such as steroids) and as germicides in wound treatment. It is also commonly used as a clarifier in alcoholic and nonalcoholic beverages. This chapter describes the methods of crospovidone preparation and discusses its physical properties and primary uses. The primary pharmaceutical application of crospovidone is that of a tablet disintegrant, although it can also function as a tablet binder. For a polymer to be useful as a pharmaceutical excipient, grades of material need to possess properties such as high swelling capacity, high capillary activity, high hydration capacity, and low bulk density. The chapter discusses the interactions of crospovidone with drug substances.

Insoluble poly-N-vinyl pyrrolidone (PVP) has been found to possess selectivity properties toward various nucleotide derivatives and can be used for column chromatography employing water as eluent. Compounds emerge from the columns in this order: nucleotides, pyrimidines, purines. Total elution volumes and times for the series of compounds investigated are 45 ml (5 h) with use of a 0.9 x 22.3 cm column and 20 ml (65 min) with use of a 0.9 x 10.8 cm column.

A column chromatographic procedure formerly applied to separations of sugar phosphates on Dowex 1 chloride has been used in resolving a variety of nucleotides and coenzymes. Group separations have been effected by this method. For further separation and purification of common nucleotides, a linear gradient procedure has been presented. In this system, Dowex 1 chloride or formate columns are used with either hydrochloric acid, formic acid, ammonium formate, or ammonium chloride as eluants