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1.
Food Chem Toxicol ; 51: 143-8, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23022013

ABSTRACT

This study has the objective of evaluating the stability of B complex vitamins and its vitamers, for a period of 1year of storage. The pollen samples were stored under room temperature (with and without light) and frozen. The vitamins were quantified by HPLC with fluorescence detection. All proposed vitamins were found in the samples and the dehydration process did not interfere in vitamin content. The variations were (dry basis): 0.59-1.09mg/100g (B(1)); 1.73-2.56 (B(2)); 6.43-15.34 (PP) and 0.33-0.68 (B(6)). After 1year of storage, it can be stated that vitamin B(1) concentration remained constant, while for the others, the concentration loss was dependent on time rather than on storage conditions. All samples were considered vitamin B(2) sources. The influence of the storage time in the concentrations of vitamin B(6) and PP was explained mathematically, through linear regression equations of multivariate analysis.


Subject(s)
Bees , Food Storage/methods , Pollen/chemistry , Vitamin B Complex/analysis , Vitamin B Complex/chemistry , Animals , Chromatography, High Pressure Liquid , Freezing , Multivariate Analysis , Riboflavin/analysis , Thiamine/analysis , Time Factors , Vitamin B 6/analysis
2.
Phytochem Anal ; 19(2): 179-83, 2008.
Article in English | MEDLINE | ID: mdl-18200605

ABSTRACT

Brazilian propolis contains several phenolic compounds among which 5 diprenyl-4-hydroxycinnamic acid (artepillin-C) is commonly found in areas where flora is rich in Baccharis species. The quantification of artepillin-C has become an important factor as an indicator of Brazilian propolis quality and the compound may be used as a chemical marker for quality control in exportating green propolis. This work was to validate the method and evaluate the content of artepillin-C from 33 samples collected in different Brazilian regions. The method used was HPLC with UV-vis detection and a reversed-phase C(18) column. The validation parameters studied were: linearity, accuracy, precision, quantification and detection limits. The results obtained were: detection limit = 0.0036 microg/mL, quantification limit = 0.012 microg/mL, accuracy = 0.0064 and 0.078, recovery 98-102%. Artepillin-C content varied from 0 to 11% depending on the geographical origin. Propolis from the southeast region presented the highest level of artepillin-C (5.0-11.0%). Whist that from the northeast region did not show any artepillin-C.


Subject(s)
Chromatography, High Pressure Liquid/methods , Phenylpropionates/analysis , Propolis/chemistry , Brazil , Chromatography, High Pressure Liquid/standards , Phenylpropionates/chemistry , Quality Control , Reproducibility of Results
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