A novel acid proteinase (Tropiase) was isolated from Candida tropicalis IFO 0589 by DE52-cellulose, and DEAE-Cosmogel column chromatographies. The purified tropiase gave a single band on disc polyacrylamide gel electrophoresis, isoelectric focusing and sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis. The enzyme preparation had a molecular weight of 23,900, isoelectric point of p...

A mild, convenient and transition metal free methodology for oxidative ipso nitration of diversely functionalized organoboronic acids, including heteroaryl- and alkylboronic acids, has been developed at ambient temperature using a combination of [bis-(trifluoroacetoxy)]iodobenzene (PIFA) - N-bromosuccinimide (NBS) and sodium nitrite as the nitro source. It is anticipated that the reaction proce...

The present study had as a goal to purify and characterize the lipolytic fraction secreted by a strain of Rhizopus sp. Only 3 steps of purification were necessary to achieve SDS-PAGE homogeneity. One band with 37.5 KDa molecular mass and with 1446 U/ mg specific activity was obtained. The purified fraction presented 2 lipase isoforms; both showed optimum activity at 50oC, and were stable betwee...

poly (n-bromosuccinimide) (pnbs) as a mild, efficient, non-acidic, polymeric and heterogeneous catalyst was applied for simple conversion of epoxides into thiiranes by treatment with kscn or (nh2)2cs at room temperature. aliphatic and aromatic epoxides converted into their corresponding thiiranes under mild conditions. all reactions proceeded in short reaction times and afforded the correspondi...