BioMed Research International / 2010 / Article / Tab 2

Research Article

Genotoxic and Cytotoxic Safety Evaluation of Papain (Carica papaya L.) Using In Vitro Assays

Table 2

Inhibition halos (mm) of the E. coli strains after treatment with different papain concentrations mixed with hydrogen peroxide. Aliquots (100  πœ‡ L) of exponentially growing cultures of E. coli were mixed with 3 mL top agar (44–46 ∘ C) and spread on LB plates supplemented with antibiotic (ampicillin or chloramphenicol, according to the strain resistance). After 15 minutes, paper discs (5 mm diameter) containing different amounts of the papain (100 or 500  πœ‡ g/disc) mixed or not with H2O2 (300  πœ‡ g/disc) were placed in the center of the plates. After 24-hour incubation at 37 ∘ C the inhibition halos around the disc were measured. Values are the mean of 3 independent experiments with standard deviations not exceeding 15% (mean Β± SD). 5% significance level was adopted to compare data.

Growth inhibition halos (mm) of E. coli strains

Agents (10  πœ‡ L/disc)IC203IC204IC205IC206IC207WP2 (WT)
uvrA oxyRuvrA umuDCuvrA umuDC mutMuvrA umuDC mutYuvrA umuDC mutM oxyR

H2O2 (300  πœ‡ g)48.0 Β± 1.430.5 Β± 2.720.0 Β± 2.417.0 Β± 2.337.7 Β± 1.016.0 Β± 0.5
Papain (100  πœ‡ g) plus H2O2 (300  πœ‡ g)45.0 Β± 0.1*22.0 Β± 1.8*21.5 Β± 1.816.5 Β± 1.733.5 Β± 1.0**15.6 Β± 0.4
Papain (500  πœ‡ g) plus H2O2 (300  πœ‡ g)40.5 Β± 0.9*22.0 Β± 1.9*20.0 Β± 2.217.5 Β± 2.035.5 Β± 0.5**15.4 Β± 0.8
0.9% NaCl (negative control)NDNDNDNDNDND

ND: not detected.
βˆ— 𝑝 < 0 . 0 0 1 when compared to H2O2 (300  πœ‡ g/disc).
βˆ— βˆ— 𝑝 < 0 . 0 1 when compared to H2O2 (300  πœ‡ g/disc).