The photodynamic action of UV sensitized methylene blue (MB) was studied on the venom of Thailand cobra Naja siamensis. The reaction mixture comprising phosphate buffer (B), methylene blue (S), and venom protein (P) was exposed to UVR (ultra violet radiation) for 2 hours at 37°C. Stable excited species (S’) were generated by photodynamic action. These in B environment produced reduced substates SH2 and photooxidised products PO in the presence of atmospheric oxygen. Increased absorbance (OD) of the reaction mixture after UVR with a corresponding loss of protein was suggested to be due to the formation of photooxidised venom products. The detoxification profile of venom protein using visible radiation in the presence of MB and oxygen appeared similar to the profile using UVR.
Thailand cobra; Naja siamensis; photosensitization; photooxidation; detoxification
