Inhibition of toxic actions of phospholipase A(2) isolated & characterized from the Indian Banded Krait (Bungarus fasciatus) venom by synthetic herbal compounds

BACKGROUND & OBJECTIVES: Phospholipase A(2) (PLA(2)) is one of the major constituents of krait venom associated with several pathophysiological actions like myotoxicity, cardiotoxicity, neurotoxicity, etc. As there was no specific antiserum available against Bungarus fasciatus venom, this study was done with synthetic herbal compounds, anti PLA(2) rabbit antiserum and commercial polyvalent snake venom antiserum to neutralize the PLA(2) induced toxicities in experimental models. METHODS: B. fasciatus venom phospholipase A(2) fraction 38 (BF-38) was isolated by ion exchange chromatography, molecular weight was determined by mass spectrometry and its N terminal amino acid sequence was identified. Monospecific rabbit antiserum was raised against the PLA(2) in presence of Freund complete adjuvant. The neutralization of PLA(2) induced toxicities was done in in vitro and in in vivo models using synthetic herbal compounds, anti PLA(2) rabbit antiserum and commercial polyvalent snake venom antiserum. RESULTS: A toxic PLA(2) (BF-38) was purified from the B. fasciatus venom by CM-cellulose and HPLC, of 13.17 kDa and a minor band of 7.3 kDa using ESI-MS. The 13.17 kDa PLA(2) sequence was NLYQFKNMIQC. The 7.3 kDa toxin sequence was RKCLTKYSQDNES and was found to be <10 per cent w/w. Anti PLA(2) rabbit antiserum produced faint precipitant band in immunogel diffusion and showed low titre value. The commercial polyvalent snake venom antiserum, anti PLA(2) rabbit antiserum and the synthetic herbal compounds neutralized the PLA (2) induced toxicities at different intensities. INTERPRETATION & CONCLUSIONS: Our results suggested that synthetic herbal compound (BA) along with antiserum might provide effective protection against PLA(2) induced toxicities of B. fasciatus venom.