Biological investigation of lichen Usnea Complanata (Mill, Arg) Mot.
C.Reni charles,Lecturer,Department of pharmacy services, Christian medical college, vellore.

Lichens are peculiar plants consisting of a fungus and an algae. The biological property particularly Cytotoxic activity was investigated in this lichen. The coarse powder of the Lichen was extrated with chloroform, acetone, methanol. The extracts were used to determine the Invitro Cytotoxicity by Dye Exclusion Method. Nearly 6 x 103 cells were seeded in 96 well microlitre plate 24 hours prior to the beginning of the test. The cells were exposed to the series of test substances diluted with minimum essential medium containing 2% serum for 72 hours at 370C in 5% CO2 incubator and the cells were periodically checked for granularity, vacuolation shrinkage, swelling and any other morphological changes.

The medium was discarded and the cells in each well were trypsinized with 50 microlitre of TPVG solution for 2-3 minutes..The cells were then mixed with 0.4% trypan blue in the ratio of 1:1 and the cells were counted using the haemocytometer.

All the three extracts showed cytotoxicity. In high concentrations, the cell inhibition % is from 60-100% and at low concentration, the range is 10-35%. Hence these extracts can be given for anticancer and antiviral studies, particularly metastasis and anchorage independent cancer. ..

References:
1. Lumbsh, H.T., Lichenologist (London) 27(3): 161-167.

2. Asdornnithee, s., Himeji, E., Akiyama, K., Sasaki, T., Takata, R., T.of Fermentation
and Bioengineering 79(3): 200-4 (1995).

3.Ingofsdottir, k., Hjalmarsdottir, M.A., Sigurdsson, A., Gudjonsdottir, G.A.,
Brynjolfsdottir, A., Steingrimsson, O., Antimicrob. Agents Chemother 41(1); 215-7
(1997).

Author's Bio: 

Lecturer, Christian medical college, Vellore.