Liquid paraffin

About: Liquid paraffin is a research topic. Over the lifetime, 6185 publications have been published within this topic receiving 52956 citations.

Glucuronidation of R- and S-ketoprofen, acetaminophen, and diflunisal by liver microsomes of adjuvant-induced arthritic rats.

Abstract: The effect of adjuvant-induced arthritis on hepatic microsomal glucuronidation was studied in the rat. Arthritis was induced by injection of Mycobacterium butyricum suspended in liquid paraffin. Vmax and the Michaelis-Menten constant values for the in vitro glucuronidation of R- and S-ketoprofen, acetaminophen, and diflunisal by liver microsomes obtained from control and adjuvant-induced arthritic rats were compared. In addition, uridine 5'-diphosphate-glucuronosyltransferase activity toward bilirubin and p-nitrophenol, as well as levels of cytochrome P-450 and beta-glucuronidase were determined in these microsomal preparations. Adjuvant-induced arthritis resulted in a significant reduction in hepatic cytochrome P-450 levels and in p-nitrophenol glucuronidation (5.65 +/- 0.40 versus 2.58 +/- 0.27 micromol.min/mg protein in control and arthritic rats, respectively, mean +/- S.E.M.). Glucuronidation of bilirubin and beta-glucuronidase activities in liver microsomes and in plasma were not affected by adjuvant-induced arthritis. Vmax (nmol/min/mg protein) for the formation of R-ketoprofen glucuronide, S-ketoprofen glucuronide, diflunisal phenolic glucuronide, and diflunisal acyl glucuronide was significantly decreased in arthritic rats (0.68 +/- 0.10, 0.77 +/- 0. 12, 0.044 +/- 0.005, 0.26 +/- 0.03, respectively) compared with control rats (1.45 +/- 0.04, 1.60 +/- 0.04, 0.087 +/- 0.008, 0.46 +/- 0.04, respectively). Glucuronidation of p-nitrophenol, ketoprofen and diflunisal, substrates which seem to be at least partly glucuronidated in the rat by isoenzymes of the UGT2B subfamily, was impaired in adjuvant-induced arthritis. Glucuronidation of bilirubin and acetaminophen, substrates of UGT1- isoenzymes, was not affected by adjuvant-induced arthritis. It seems, therefore, that adjuvant-induced arthritis in the rat leads to impaired glucuronidation of substrates of the UGT2B subfamily.

Synthesis of highly stable γ-Fe2O3 ferrofluid dispersed in liquid paraffin, motor oil and sunflower oil for heat transfer applications

Abstract: This article aims at the synthesis of highly stable γ-Fe2O3 magnetic nanoparticles and their ferrofluids using different base liquids such as liquid paraffin, motor oil and sunflower oil for heat transfer applications. Phase and morphology of the synthesized nanoparticles were probed using XRD, SEM and FTIR spectroscopy. The average nanoparticle size of γ-Fe2O3 magnetic nanoparticles was found to be 13 nm. Stability of the ferrofluids was monitored by visually observing the aggregation nature of the nanoparticles for 180 days. The ferrofluid prepared using motor oil as a base fluid exhibited high stability (for more than 1 year) and a mean enhancement of 77% in thermal conductivity at 1.5 vol% nanoparticles was observed as compared to base fluid. The viscosity of the ferrofluids was also measured and found to be 18, 38 and 8 cP at 27 °C for the liquid paraffin based, motor oil based and sunflower oil based ferrofluid, respectively.

Mosquito repellent activity of piper guineense and xylopia aethiopica fruits oils on aedes aegypti

Abstract: Repellent activity of Piper guineense and Xylopia aethiopica fruits oils in liquid paraffin were evaluated against adult Aedes aegypti in the laboratory. Results showed that repellency is dependent on both the concentration and time after application. P. guineense and X. aethiopica oils showed complete protection from mosquito bite for 2h at 35%(v/v) and 30% respectively. The activity of eucalyptus oil (positive control), a commercial repellent, at 30% was only able to protect for 2h. Both oils used could be applied as repellents where protection from mosquito bite is sought for, over a short period of time.

The sensory analysis and identification of volatiles from walnut (Juglans regia L.) headspace

Abstract: This paper has the two-fold aim of illustrating the application of techniques recently developed in this laboratory and of elucidating the nature of the compounds responsible for the aroma of a particular foodstuff. The volatile constituents of Chaberte walnuts (Juglans regia L.) headspace were investigated using charcoal capillary traps. By means of capillary columns and a g.c.-m.s. system some 37 compounds were identified, including six aldehydes, six alcohols, and five ketones. It was shown that the aroma of walnuts is composite in nature, since none of the components was found to possess a walnutty aroma on elution from g.c. columns, yet the total headspace, retrapped on a length of PLOT Celite capillary, was found to be extremely walnutty. Further sensory analysis using PLOT Celite traps revealed that the carbonyls present in a particular region of the chromatogram were important to the aroma of walnuts. A mixture in liquid paraffin of certain carbonyls identified in the headspace was found to possess a moderately walnutty aroma.

Heat-resistant liner-provided vessel closure and process for preparation thereof

Abstract: Disclosed is a vessel closure having a liner formed from a composition comprising (i) a hydrogenated styrene/butadiene block copolymer having a melt index smaller than 0.1 g/10 min as measured at a temperature of 200° C. under a load of 5 kg, (ii) liquid paraffin and (iii) a propylene resin. In this liner, the compression permanent strain and permanent elongation under high temperature conditions are extremely small, and therefore, even if a divergence is produced between the liner and the mouth portion of a vessel by thermal deformation or thermal shrinkage, a good sealing property can be maintained.