FT-IR spectra of liver tissue isolated from mice, Mus musculus, have been recorded in the region of 4000 - 400 cm-1 for normal, mercury treated and recovery phase. In this study, the total protein content was found to be decreased in the liver tissues after treatment with median-lethal dose of mercuric chloride. The marked fall in the level of bio-chemical constituent in the tissue due to metal exposure indicates the rapid initiation of the breakdown of the bio-chemical constituents to meet the energy demand during toxic stress. During the recovery phase, the decreased levels of bio-chemical constituents are restored to near normal level. Methanol fractions of Tribulus terrestris fruit extract was administrated on mercury intoxicated mice for 15 days. After the administration, the mercury-intoxicated animals slowly recovered from the adverse effect of mercury poisoning with the help of plant bio-formulations. The results are discussed in detail.