Bharati Adawadkar

Inhibitory activity of xanthine oxidase and superoxide-scavenging activity in some taxa of the lichen family Graphidaceae

Results on the screening of species of the lichen family Graphidaceae for superoxide-scavenging activity (SSA) and xanthine-oxidase inhibitory (IXO) activity have been presented. The potential of the extracts for scavenging of superoxide and inhibition of xanthine-oxidase under various physiological conditions has been evaluated. The methanolic extracts of the species of family Graphidaceae showed inhibitory properties of xanthine oxidase (IC50 = 2.0 to 5.26 microg/ml) with an additional superoxide scavenging capacity (IC50 = 3.63 to 13.88 microg/ml). The potential of the methanolic extracts for scavenging of superoxide and inhibition of xanthine oxidase remained stable at 4 degrees C. Thus the extracts can be maintained for longer periods for their therapeutic uses.

Trans-septate species of Acanthothecis and Fissurina from India

Eighteen species in the lichen genera Acanthothecis Clem. and Fissurina Fee (Graphidaceae) with colourless, trans-septate ascospores are recorded from India. Eight new species, namely Acanthothecis collateralis, Fissurina capsulata, F. coarctata, F. karnatakensis, F. khasiana, F. longiramea, F. taeniocarpoides and F. verrucosa, and a new variety, F. dumastioides var. salazinica, are described. Fissurina saxicola ad int., clearly distinguished from the other species is recorded, but is not formally described as new to science as the material is scanty. Acanthothecis consocians, F. globulifica, F. insidiosa and F. rugosa are reported for the first time from India. A key for the trans-septate species of Acanthothecis and Fissurina in India is provided.

Tyrosinase-inhibitory activity in some species of the lichen family Graphidaceae.

Twenty-five species of the lichen family Graphidaceae have been investigated for tyrosinaseinhibitory activity. Tyrosinase-inhibiting material was extracted with solvents methanol, acetone, ethanol, dimethyl sulphoxide in water, and with water only. Methanol has been found to be suitable for extracting adequate amounts of tyrosinaseinhibiting component from the natural thallus. The lichen species such as Graphina glaucorufa, Graphina multistriata, Graphina salacinilabiata, Graphis assamensis, Graphis nakanishiana, and Phaeographopsis indica, have shown inhibition of tyrosinase over a range of 30-78%. Half-inhibiting concentration (IC50, J.g/ml) has been found to be much lower than the standard tyrosinase inhibitors and thus can compete with other commercially available tyrosinase inhibitors. The extracts of these species have been found to be stable at 4°C.

A new isidiate species of Graphis from India

A new isidiate species in the genus Graphis Adans. ( sensu Staiger 2002), Graphis isidiza ( Graphidaceae , ascomycetes) is described from the Western Ghats of India.