(R)-1-Chloro-3-(1-naphthyloxy)-2-propanol, which is the key intermediate of (S)-propranolol, was successfully prepared via enantioselective transesterification catalyzed by lipase under ultrasound irradiation. Compared with conventional shaking, the enzyme activity and enantioselectivity were dramatically increased under ultrasound exposure. Effects of various reaction conditions on the synthet...

pretreatment of adults of iraq strain of afhstephenst with a sub-letlial dose of pcrmethrin resulted in a 65% enliancemenl of tolerance to this insecticide. similarly, pre-exposure of dub-lpr larvae to a sub-lethal dose of pcrmethrin resulted in increased tolerance to pcrmethrin. for the sensitive ind-s strain, the inductive effect was smaller. tiie results of bioassays of resistant and suscept...

Alpha toxin derived from Clostridium perfringens was used for diagnosis of Streptococcus agalactiae (St.agalactiae) by rapid and spot CAMP tests. The selected Cl.perfringens strain was cultured in optimized conditions; the supernatant of culture was concentrated by ultra filter and purified by DEAE cellulose chromatography. The efficacy of both purified and crude α-toxins were examined by rapid...

The binding behavior of a competitive inhibitor, N-phenylbenzhydroxamic acid (BHA) against horseradish peroxidase (HRP) was studied in order to understand and predict the interaction mechanism of hydrogen donors with the enzyme. The dissociation constants of the complexes of HRP-BHA, HRP-donor and HRP-BHA-azide were estimated at specified conditions by difference spectroscopy. The binding s...

Bacillus sp. can biosynthesize fibrinolytic enzymes. Culture conditions and nutrient sources are important factors affecting microbial growth production of the Fibrinolytic enzyme. Therefore, we investigated culture strain ES4, such as temperature, pH, C source (glucose, sucrose, glycerol, maltose), N (yeast extract, meat content, peptone, tryptone), metal ions (Ca 2+ , Mg Mn Zn K + Fe Cu ), ti...