Essential oil ofArtemisia scoparia
The chemical composition of the essential oil of oriental wormwood growing in Kazathstan has been investigated. Of the components of the oil, 28 have been identified, and the structure of an acetylenic hydrocarbon has been refined.
Chemical examination ofArtemisia scoparia Waldst. and Kit
Summary and Conclusion1.From the flowering heads and seeds ofArtemisia scoparia, which is the only species ofArtemisia growing in the plains of India, a lactone and an essential oil have been obtained in yields of 0·92 and 0·75 per cent. respectively.2.The lactone, which has been named “Scoparin”, has been found to have the molecular formula C16H20O5. It contains an α: β-unsaturation, one ketonic group and two methoxyl groups.3.A number of derivatives of the lactone have been prepared and analysed.
Characterization and gene cloning of a maltotriose-forming exo-amylase from Kitasatospora sp. MK-1785
A maltotriose-forming amylase (G3Amy) from Kitasatospora sp. MK-1785 was successfully isolated from a soil sample by inhibiting typical extracellular α-amylases using a proteinaceous α-amylase inhibitor. G3Amy was purified from the MK-1785 culture supernatant and characterized. G3Amy produced maltotriose as the principal product from starch and was categorized as an exo-α-amylase. G3Amy could also transfer maltotriose to phenolic and alcoholic compounds. Therefore, G3Amy can be useful for not only maltotriose manufacture but also maltooligosaccharide-glycoside synthesis. Further, the G3Amy gene was cloned and expressed in Escherichia coli cells. Analysis of its deduced amino acid sequence revealed that G3Amy consisted of an N-terminal GH13 catalytic domain and two C-terminal repeat starch-binding domains belonging to CBM20. It is suggested that natural G3Amy was subjected to proteolysis at N-terminal region of the anterior CBM20 in the C-terminal region. As with natural G3Amy, recombinant G3Amy could produce and transfer maltotriose from starch.