Isotamarixen - a new antioxidant and prolyl endopeptidase-inhibiting triterpenoid from Tamarix hispida.

A new pentacyclic triterpenoid, 3alpha-(3",4"-dihydroxy- trans-cinnamoyloxy)- D-friedoolean-14-en-28-oic acid ( 1) has been isolated along with two known compounds, rhamnocitrin ( 2) and isorhamnetin ( 3) from the aerial parts of Tamarix hispida Willd. Compound 1 was found to be a potent antioxidant. In addition, compounds 1 - 3 showed significant inhibitory activity against prolylendopeptidase (PEP).

Antioxidant and antimicrobial activities of Tamarix ramosissima.

The ethylacetate and water-acetone extracts of Tamarix ramosissima were screened for their antioxidant, antibacterial, antifungal and DNA damaging activities through in vitro experiments. All fractions as well as precipitates showed significant antioxidant activity. A known compound tamarixetin (1) was isolated which showed significant DNA damaging activity in mutant yeast bioassay.