Lipases produced by a newly isolated Sporidiobolus pararoseus strain have potential catalytic ability for esterification reactions. After production, the enzymatic extracts (conventional crude and ...precipitated, 'CC' and 'CP', and industrial crude and precipitated, 'IC' e 'IP') were partially characterized. The enzymes presented, in general, higher specificity for short chain alcohols and fatty acids. The precipitated extract showed a good thermal stability, higher than that for crude enzymatic extracts. The 'CC' and 'CP' enzymes presented high activities after exposure to pH 6.5 and 40 °C. On the other hand, the 'IC' and 'IP' extracts kept their activities in a wide range of pH memory but presented preference for higher reaction temperatures. Preliminary studies of application of the crude lipase extract in the enzymatic production of geranyl propionate using geraniol and propionic acid as substrates in solvent-free system led to a reaction conversion of 42 ± 1.5%.
The lipase produced by a newly isolate
Sporidiobolus pararoseus
strain has potential catalysis ability for esterification reactions. In order to improve its synthetic activity, this work aimed at ...optimizing ‘synthetic lipase’ production by submerged fermentation of a conventional media based on peptone, yeast extract, NaCl and olive oil using experimental design technique. According to the results obtained in the first experimental design (2
4–1
), yeast extract and NaCl concentrations were tested to further optimization by response surface methodology. The maximum ‘synthetic lipase’ activity obtained was 26.9 U/mL in the optimized media (5.0, 6.8, 7.0 and 1.0% (wt/v) of peptone, yeast extract, NaCl and olive oil, respectively), representing a 6.36-fold increase compared to the initial medium. The time course of ‘synthetic lipase’ production in the optimized condition was evaluated in terms of synthetic activity, protease activity, biomass and total carbon and the maximum synthetic activity was observed during the stationary phase of growth.
A representative sample of 855 Hong-Kong Chinese children aged 36-48 months were assessed using the BSQ and the PBCL. Good reliability for both instruments were found. For the BSQ and PBCL, 12.75% ...and 27.5% were above the cut-off points of 10+ and 12+ respectively and 5.9% were above both cut-off points. In the second stage, 234 subjects were recruited by stratified random sampling according to the results of the screening state. A clinician interviewed the parent, child and teacher before making a diagnosis. The prevalence of behaviour disorder was: nil, 53.7%; dubious, 23.1%; mild, 18.0%; moderate, 4.5%; and severe, 0.7%. There were significantly more boys in the categories mild, moderate and severe.
For the majority of workers, regular use of latex gloves causes no problems. For a minority, however, using latex gloves or even just being near them can result in a range of adverse reactions. This ...has a number of implications for hand and skin protection programs where latex gloves are used. There are many kinds of allergic reactions. Only 2 - Type I and Type IV - have been observed among latex-sensitive people. A particular individual may suffer from one or more of 3 reactions: 1. irritant contact dermatitis, 2. allergic contact dermatitis (Type IV), and/or 3. immediate allergic reaction (Type I). Workers should be aware of the potential health effects related to latex sensitivity so that adverse reactions can be recognized and preventive steps taken before symptoms become severe. It is commonly believed, but not yet proven, that workers become allergic to latex only after a substantial period of exposure. Latex protein exposure of the worker comes from 2 main sources: the gloves worn by the worker and the air breathed. Several steps are discussed that an employer can take to minimize employee exposure to latex protein allergens.
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