Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Furaldehyde”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

Mutagen formation in browning model systems.

A browning model system, consisting of diacetyl and ammonia, produced frameshift and base-pair substitution mutagens when the system was heated over 20 min and 120 min, respectively. The major product was 2,4,5- trimethylimidazole , which showed no mutagenicity toward Salmonella typhimurium strains TA98 and TA100 with or without metabolic activation. When furfural was reacted with nitrate under mild conditions (for 30 min to 3 h at 0-25 degrees C and pH 2-7), it did not produce mutagenic nitrofuran derivatives. However, the ethyl ether extract obtained from the reaction mixture of furfural and nitrate with hydrochloric acid exhibited strong mutagenic activities toward S. typhimurium strains TA98 and TA100 in the presence of metabolic activation. The major product of this reaction mixture, 4- nitrofurfural , exhibited no mutagenicity toward tester strains TA98 and TA100 with or without metabolic activation. Pure active mutagen(s) was (were) not, however, identified in either system.

Ammonia↗

Inhalation toxicity of furfural vapours: an assessment of biochemical response in rat lungs.

The pulmonary biochemical response, particularly the effects on mixed-function oxidases, was investigated in rats exposed to 40 ppm furfural for 1 h daily, 5 days per week, for periods of 7, 15 and 30 days. This concentration is ca. 22% of the acute LC50 dose. Exposure to furfural increased the activities of acid and alkaline phosphatases and glutamic-pyruvic transaminase, inhibited the activities of arginase and succinic dehydrogenases and elevated the concentration of lactic acid in the lungs. In the group of mixed-function oxidases, the activities of aminopyrene-N-demethylase and aniline hydroxylase (phase I, cytochrome P-450b specific) significantly increased and the activity of Benzo[a]pyrene hydroxylase (phase I, cytochrome P-450c specific) decreased. The activity of glutathione-S-transferase (phase II component) also was increased concurrently with a decrease in the concentration of glutathione. The magnitude of biochemical alterations in most cases was related directly to the duration of exposure. Our observations indicate that furfural caused pulmonary irritation, parenchymal injury and the regenerative proliferation of type II pneumocytes. Selective (cellular and/or cytochrome P-450 isozyme specific) enhancement of pulmonary mixed-function oxidases by furfural appears to stimulate its own pulmonary biotransformation, and the excretion of oxidative metabolites was facilitated by their enzymatic conjugation with glutathione.

Acid Phosphatase↗

Impurities in a morphine sulfate drug product identified as 5-(hydroxymethyl)-2-furfural, 10-hydroxymorphine and 10-oxomorphine.

Stability testing of morphine sulfate formulated with nonpareil sugar seeds (consisting of sucrose and starch) and fumaric acid revealed the formation of the three impurities 5-(hydroxymethyl)-2-furfural, 10-hydroxymorphine and 10-oxomorphine. 5-(Hydroxymethyl)-2-furfural was isolated via semipreparative HPLC utilizing volatile mobile phase constituents and was identified by analysis of its HRMS and NMR spectra. 10-Hydroxymorphine and 10-oxomorphine were obtained via semipreparative HPLC and subsequent removal of ion-pair reagents using an anion exchange resin, or by solid phase extraction, and identified by spectroscopic analysis followed by comparison with authentic materials. 5-(Hydroxymethyl)-2-furfural is a degradation product of hexose sugars, and its formation in the presence of morphine sulfate formulated with fumaric acid suggests that caution should be exercised when including nonpareil seeds in formulations that contain acidic drug salts and/or acid excipients. The preliminary results of tests on the interaction of acidic salts of some other drugs with nonpareil seeds are presented.

Chemistry, Pharmaceutical↗

Study on fluorescence of Maillard reaction compounds in breakfast cereals.

During the advanced stage of the Maillard reaction (MR) in food processing and cooking, Amadori rearrangement products undergo dehydration and fission and fluorescent substances are formed. Free and total (free + linked to the protein backbone) fluorescence (FIC) due to Maillard compounds in 60 commercial breakfast cereals was evaluated. Pronase was used for efficient release of linked fluorescent Maillard compounds from the protein backbone. Results were correlated with some heat-induced markers of the extent of the MR or sugar caramelisation during cereal processing, such as hydroxymethylfurfural, furfural, glucosilisomaltol and furosine. The effect of sample composition (dietary-fibre added, protein, etc.) on levels of FIC, expressed as fluorescence intensity (FI) per milligram of sample, is discussed. FIC is significantly correlated to the protein content of the sample and fluorescent Maillard compounds are mainly linked to the protein backbone. The ratio of total-FIC to free-FIC was 10.4-fold for corn-based, wheat-based and multicereal-based breakfast cereals but significantly higher in rice-based samples. Addition of dietary fibre or honey increased the FIC values. Data support the usefulness of FIC measurement as an unspecific heat-induced marker in breakfast cereals.

Dietary Fiber↗

Analysis of 5-hydroxymethylfurfual in coffee, dried fruits and urine.

5-Hydroxymethylfurfural has become a substance of interest since recent results showed a possible carcinogenic potential in consequence of a metabolic activation by sulfotransferases. 5-Hydroxymethylfurfural is formed either by acid catalysed degradation of reducing sugars or via the Maillard reaction. This work provides an overview of foods potentially containing high amounts of 5-hydroxymethylfurfural. It comprises dried fruits with a high sugar content that were exposed to heat for a long time. The concentration ranges from very low in, e. g. figs (1 mg/kg) to plums that contained up to 2,200 mg/kg. Several types of roasted coffee were analysed that contained from 300 to 2,900 mg/kg of 5-hydroxymethylfurfural. In a small human study with seven healthy volunteers the urine excretion of unmetabolised 5-hydroxymethylfurfural was investigated. After uptake of 20 g of plum jam containing 24 mg of 5-hydroxymethylfurfural, 163 microg (mean) were excreted within 6 h, an equivalent of 0.75% of the ingested 5-hydroxymethylfurfural.

Adolescent↗