Contact dermatitis to polyester spin finishes
A female laboratory assistant, aged 28, showed yellow stained palms and nails when examined for paronychia of two fingers. Determination of amylase involved contact with dinitro salicylic acid (DNSA) in several steps. It was found that plastic gloves used in dishwashing the utensils were rapidly penetrated by DNSA. Though she did not work with DNSA for 4 months, the yellow stains did not disappear. Yellow stains were now also observed on her cheeks and soles. For about 2 months she had been taking a drug containing Nitrazepam, 5phenyl-7-nitro-lH -1.4-benzodiazepin-2(3H)-on. She stopped using Nitrazepam and the yellow staining decreased, but when she again beg~n to have contact with DNSA in her work, the yellow stains had not disappeared completely. They increased again on palms and nails but not on cheeks or soles. She then moved to another place and it has not been possible to examine her again. It is obvious that the patient's skin was first stained yellow by DNSA. It can only be suspected but not established with certainty that Nitrazepam gave yellow stains on her cheeks and soles. We did not find reports on yellow staining from Nitrazepam, nor does the manufacturer have any such reports on file. It is known that aromatic nitro compounds stain skin, nails and hair yellow. Thus explosives, e.g. trinitrotoluene, give such staining. Some of the aromatic nitro compounds are yellow and can then stain by simple contamination. However, there is staining by chemical reaction, but the nature of this reaction seems to be only partly studied. Aromatic nitro compounds might combine with amino acids in three ways: The phenols act as weak acids and form salts with aminogroups in basic amino acids, e.g. histidine, lysine and argmme. DNSA acts in the same way. Aromatic nitro compounds may form charge transfer complexes with aromatic rings. Some amino acids, e.g. tryptophane, tyrosine and phenylalanine contain such rings. When the aromatic nitro compounds contain, for example, a halogen or a sulfonyl group, they may form covalent linkages with amino acids. Many of the aromatic nitro compounds are yellowish and the compounds formed may therefore become stained. Particularly the covalent linkage can change the color and strong yellow staining may arise from weak or uncolored aromatic nitro compounds.
Evaluation of the fragrance mix in the European standard series
Patients and Methods During 1994–1998, 757 of our outpatients, suspected of allergy to cosmetics, were patch-tested with the European standard series, including fragrance mix, and with its 8 separate components: oakmoss, iso-eugenol, eugenol, hydroxycitronellal, cinnamic alcohol, cinnamic aldehyde, geraniol and a-amyl-cinnamic aldehyde (2% in sorbitan sesquioleate 1%). All test substances were supplied by Hermal TrolabA (Reinbek, Germany). Test results were analysed retrospectively.
Effect of Aeration and Agitation Regimes on Lipase Production by Newly Isolated Rhodotorula mucilaginosa–MTCC 8737 in Stirred Tank Reactor Using Molasses as Sole Production Medium
The influence of media and process parameters (aeration and agitation) on fermentation broth rheology and biomass formation has been studied in 1.5-l stirred tank reactor for lipase production using Rhodotorula mucilaginosa MTCC 8737. Molasses, as sole production medium, is used for lipase production by varying aeration (1, 2, and 3 vvm) and agitation speeds (100, 200, and 300 rpm). Maximum lipase activity of 72 U/ml was obtained during 96 h of fermentation at 2 vvm, 200 rpm, pH 7, and 25 ± 2°C temperature. Lipase production kinetics with respect to dry cell weight of biomass showed YP/S of 25.71 U/mg, specific product formation of 10.9 U/mg DC, and YX/S 2.35 mg/mg. Maximum lipase activity (MC 2) of 56 U/ml was observed at 1% molasses, and a further increase in the molasses concentration of (%) 1.5 and 2 inhibited the product formation of lipase with 15 and 8.5 U/ml, respectively. The production kinetics of molasses media showed YP/X was 14 U/mg DC, YP/S 16 U/mg, and YX/S 1.14 mg/mg during 96 h of bioreactor operation. The kLa values for all batches (MC 1–MC 4) at 96 h of fermentation were 32, 28, 21, and 19/h, and the |oxygen transfer rate were 54.4, 56, 35.7, and 17.29 mg/l h, respectively. Increase in molasses concentration resulted in decreased lipase activity by increase in viscosity of the fermentation broth.