Biological evaluation and study of polysaccharides of Dalbergia sissoo Roxb growing in Egypt

The extracts of Dalbergia sissoo Roxb growing in Egypt, the polysaccharides prepared from leaves, stem and bark and the major constituent in the plant [biochanin A] were subjected to screening of anti-inflammatory, anti-pyretic and analgesic activities adopting new methodology. The anti-tumor, anti-oxidant, and antimicrobial activities of these substances were also examined. Since the polysaccharides prepared from different organs [leaves 2.5%, stem 2.2%, bark 1.2%] possessed anti-inflammatory activities, they were subjected to further phytochemical studies, using paper chromato-graphy and GC/MS analysis. The polysaccharides were heterogeneous in nature and lacked uronic acids. The use of GC/MS to study the monomeric composition of polysaccharides in the acid hydrolysate indicated that the leaf polysaccharides consist mainly of rhamnose [77%] in addition to glucose [23%]. The stem polysaccharide consists of rhamnose [47%], glycerol [46%] and galactose [7%]. The bark polysaccharide consists of rhamnose [18%], fructose [2.5%], glucose [74.5%] and galactose [6%]

Microbial transformation of emetine into o-methyl psychotrine

Several microorganisms [fungi and bacteria] were screened for their ability to biotransform emetine. Cunninghamella blackesleeana MR.-198 was selected for scale-up transformation, as it showed a major transformation product and a small amount of unidentified minor product, in addition to untransformed emetine. The major metabolite was characterized using one and two dimensional NMR techniques as O-methylpsychotrine. Further confirmation was carried out by direct comparison with a reference sample prepared by methylation of psychotrine

Microbiological transformation of diclofenac

Microbiological transformation of diclofenac has been investigated using nineteen microbial species. The study showed that most organisms metabolized diclofenac sodium to different extents, to yield three metabolites that were identified by 2D NMR and MS analyses. The major metabolite was found to be 4hydroxydiclofenac while the other two were 5-hydroxydiclofenac and 4hydroxydiclofenac lactam. The three metabolites were also obtained as mammalian metabolites of diclofenac sodium, lending further support to the concept of microbial models of mammalian drug metabolism