A method using thin-layer chromatography is described to determine the concentration of hippuric acid, mandelic acid, and phenylglyoxylic acid present in the urine after occupational mixed exposure to toluene and styrene. These substances are known metabolites of toluene and styrene, and therefore the evaluation to mixed exposure to toluene and styrene may be carried out separating these metabo...

Kinetics of oxidation of phenyl acetic acid and DLMandelic acid by potassium permanganate in aqueous acetic acid and perchloric acid mixture reveals that the kinetic orders are first order in oxidant, first order in H+ and zero order in substrate for phenyl acetic acid. DL-Mandelic acid exhibits first order in oxidant and zero order in substrate. The results are rationalised by a mechanism invo...

MANDELIc acid, when administered to animals, may be recovered almost quantitatively from the urine. Moreover, when mandelic acid appears in the body as the result of metabolic processes, it is supposed to be excreted without further change [Knoop, 1905; Dakin, 1922; Quick, 1928]. Neubauer [1909], Neubauer & Fischer [1910], Neubauer & Gross [1910] and Neubauer & Warburg [1910] claimed that after...

Mandelic acid has been used in medicine for many years as a urinary antiseptic. Methenamine mandelate (Mandelamine®, Parke-Davis, Morris Plains, NJ) has the urinary antiseptic action of both methenamine and mandelic acid. In concentrations of 35g to 50g/100L of urine, it inhibits Staphylococcus aureus, bacillus proteus, escher ichia col i , and aerobacter aerogenes. Chemically, mandelic acid ha...

OBJECTIVES (S)-Mandelate dehydrogenase (SMDH) and laccase were immobilized on chitosan. The bi-enzymatic system with immobilized SMDH and immobilized laccase was taken to catalyze the stereoselective transformation of racemic mandelic acid and (R)-mandelic acid was obtained from its racemic mixture. RESULTS Characteristics of the immobilized enzymes were valuated. The optimum pH and temperatu...

Mandelic acid is a chiral metabolite of the industrial pollutant styrene and is used in chemical skin peels, as a urinary antiseptic and as a component of other medicines. In humans, S-mandelic acid undergoes rapid chiral inversion to R-mandelic acid by an undefined pathway but it has been proposed to proceed via the acyl-CoA esters, S- and R-2-hydroxy-2-phenylacetyl-CoA, in an analogous pathwa...

Studies were carried out on two groups to styrene-based resin. Early morning urinary mandelic acid concentrations after two days without exposure correlated with reaction time measured on arrival at work. Men were found to differ considerably in their rate of clearance of mandelic acid-those with slow reaction times. After some months at reduced exposure, a small group of men with previously hi...

The effect of a dose of alcohol on the kinetics of mandelic acid excretion in four volunteers exposed to 220 mg/m3 styrene has been investigated under controlled exposure chamber conditions. Ethanol inhibited the excretion of mandelic acid, so that the peak excretion was delayed from the end of the exposure period until three hours afterwards. One hour after administration of ethanol blood mand...

Patients suffering from phaeochromocytomata excrete many times the normal amount of noradrenaline in the urine (Euler, 1951). Determination of the excretion of noradrenaline in thu urine over 24 hours is thus a valuable aid to the diagnosis of this condition. Few clinical laboratories, however, have the facilities for noradrenaline assay, and there is a need for a simple, reliable, and fairly r...

INTRODUCTION Azelaic acid and mandelic acid are superficial peels commonly applied in people of various age groups. As they are mild and do not cause any side effects, they are also often used in elderly people. AIM To compare the influence of azelaic and mandelic acid peels on facial sebum secretion in mature women aged 49-71 years. MATERIAL AND METHODS The level of secreted sebum was meas...