10.22376/ijpbs.2019.10.1.p1-12 Volume 5 Issue 4 2014 (October - December) The present investigation was carried out by ten bacterial species, lessThan i greaterThan Bacillus subtilis, Escherishia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Micrococcus luteus, Pseudomonas aeruginosa, Pseudomonas putida, Proteus mirabilis, Proteus vulgaris, Staphylococcus aureus lessThan /i greaterThan and five fungal species, lessThan i greaterThan Aspergillus terreus, Penicillium aurantiogriseum, P.expansum, Paceliomycs varioti lessThan /i greaterThan , lessThan i greaterThan Fusarium graminarium lessThan /i greaterThan were screened for their sensitivity against ochratoxin A (OTA) produced by lessThan i greaterThan Penicillium verrucosum lessThan /i greaterThan . lessThan i greaterThan Proteus mirabilis lessThan /i greaterThan was highly sensitive followed by lessThan i greaterThan E.aureogens, lessThan /i greaterThan lessThan i greaterThan B.subtilis lessThan /i greaterThan and lessThan i greaterThan K. pneumoniae. lessThan /i greaterThan Rest of the bacteria was intermediate in their sensitivity when compared with the streptomycin as standard. Similarly lessThan i greaterThan P.aurantiogriseum lessThan /i greaterThan and lessThan i greaterThan Paeciolomyces varioti lessThan /i greaterThan were comparatively more sensitive than the other fungi under study. lessThan i greaterThan Aspergillus terreus lessThan /i greaterThan and lessThan i greaterThan P.expansum lessThan /i greaterThan was sensitive to an intermediate extent. Simultaneously the DNA damaging activity of OTA was also evaluated by lessThan sub greaterThan P lessThan /sub greaterThan RSET-B plasmid DNA treated with H lessThan sub greaterThan 2 lessThan /sub greaterThan O lessThan sub greaterThan 2 lessThan /sub greaterThan plus different concentrations of OTA. The highest DNA stand breaks was observed on even at 25µg/ml of OTA and complete degradation of DNA stand breaks was observed on 30µg/ml of OTA. VANKUDOTH KOTESWARA RAO AND SIVADEVUNI GIRISHAM Penicillium verrucosum, Ochratoxin A, Antimicrobial, Antibacterial, DNA damaging activity. 335-341