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1.
J AOAC Int ; 91(1): 21-32, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18376582

RESUMO

Preparations of blue cohosh (Caulophyllum thalictroides) have been used traditionally by Native Americans for medicinal purposes. Dietary supplements containing dried roots or extracts of blue cohosh rhizomes are available as dietary supplements. The safety and efficacy of these preparations have not been systematically evaluated. Recent studies indicate that ingestion of specific alkaloids in blue cohosh preparations can produce birth defects and neonatal heart failure. Blue cohosh also contains saponins, which may be responsible for uterine-stimulating effects. We determined the amounts of major alkaloids and saponins in preparations of blue cohosh by high-performance liquid chromatography (HPLC). Alkaloids and saponins were monitored with a photodiode array detector and an evaporative light-scattering detector, respectively. Profiles were compared with those of authenticated blue cohosh root extracts. Identities of the alkaloids and saponins were confirmed by HPLC/mass spectrometry and nuclear magnetic resonance spectrometry. Calculations based on the results of analyses of dietary supplements showed that maximum daily intake of alkaloids and saponins will vary with the form (e.g., root, liquid extract) and doses recommended in product labeling. Intakes may vary from < 1 to 75 mg/day for alkaloids and from about 9 to 420 mg/day for saponins.


Assuntos
Alcaloides/análise , Caulophyllum/química , Suplementos Nutricionais/análise , Saponinas/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas
2.
Lipids ; 39(1): 11-8, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15055229

RESUMO

On July 11, 2003, the U.S. Food and Drug Administration published a final rule amending its food-labeling regulations to require that trans FA be declared in the nutrition label of conventional foods and dietary supplements. The effective date of this final rule is January 1, 2006. This places some urgency on increasing the number and types of currently available foods for which there are trans-fat data. Compositional databases on trans fat content of food are currently limited. The purpose of this study was to determine the trans-fat content of a wide range of foods prior to the effective date of the new regulation. AOAC Official Method of Analysis 996.01 was modified for the analysis of trans fat in noncereal products. Food products for analysis were selected on the basis of market share and data from the USDA's 1994-1996 Continuing Survey of Food Intake by Individuals. Foods were purchased from local supermarkets, weighed, hydrolyzed, converted to FAME, and analyzed by GC. The results showed that trans fat (g/100 g fat) ranged from 0.0 to 48.8 in bread, cake, and related products; from 14.9 to 27.7 in margarines; from 7.7 to 35.3 in cookies and crackers; from 24.7 to 38.2 in frozen potatoes; from 0.0 to 17.1 in salty snacks; from 0.0 to 13.2 in vegetable oils and shortenings; from 0.0 to 2.2 in salad dressings and mayonnaises; and from 0.0 to 2.0 in dry breakfast cereals. Serving sizes for the foods included in this survey ranged from 12 to 161 g, and trans-fat levels ranged from 0.0 to 7.2 g/serving. The significant differences in trans-fat content in products within each food category are due to differences in the type of fats and oils used in the manufacturing processes.


Assuntos
Gorduras Insaturadas na Dieta/análise , Gorduras na Dieta/análise , Análise de Alimentos , Rotulagem de Alimentos/legislação & jurisprudência , Rotulagem de Alimentos/normas , Estados Unidos , United States Food and Drug Administration
3.
J AOAC Int ; 85(1): 86-94, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11878624

RESUMO

Twelve powdered and 13 liquid infant formulas were analyzed by using an extension of AOAC Official Method 996.01 for fat analysis in cereal products. Samples were hydrolyzed with 8 N HCl and extracted with ethyl and petroleum ethers. Fatty acid methyl esters were prepared by refluxing the mixed ether extracts with methanolic sodium hydroxide in the presence of 14% boron trifluoride in methanol. The extracts were analyzed by gas chromatography. In powdered formulas, saturated fatty acid (SFA) content (mean +/- SD; n = 12) was 41.05 +/- 3.94%, monounsaturated fatty acid (MUFA) content was 36.97 +/- 3.38%, polyunsaturated fatty acid (PUFA) content was 20.07 +/- 3.08%, and total trans fatty acid content was 1.30 +/- 1.27%. In liquid formulas, SFA content (mean +/- SD; n = 13) was 42.29 +/- 2.98%, MUFA content was 36.05 +/- 2.47%, PUFA content was 20.65 +/- 2.40%, and total trans fatty acid content was 0.88 +/- 0.54%. Total fat content in powdered formulas ranged from 4.4 to 5.5 g/100 kcal and linoleic acid content ranged from 868 to 1166 mg/100 kcal. In liquid formulas, total fat content ranged from 4.1 to 5.1 g/100 kcal and linoleic acid content ranged from 820 to 1100 mg/100 kcal. There were no significant differences between powdered and liquid infant formulas in concentrations of total fat, SFA, MUFA, PUFA, or trans fatty acids.


Assuntos
Ácidos Graxos/análise , Alimentos Infantis/análise , Algoritmos , Calibragem , Cromatografia Gasosa , Ésteres/análise , Humanos , Lactente , Metilação , Padrões de Referência , Reprodutibilidade dos Testes , Triglicerídeos/análise
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