Criselda Jean G. Cruz, Anne Margaret T. Garcesa, Bemboy Nino F. Subosa – (February 2007)
Philippine Science High School Western Visayas Campus – Department of Science and Technology (DOST-PSHS WVC), Brgy. Bito-on, Jaro, Iloilo City 5000, Philippines
ABSTRACT
Crocodiles and alligators have been observed to have a rapid self-healing activity. The open wounds caused by territorial disputes heal very rapidly, without the occurrence of an infection. No study has yet been performed on the actual line of defense that causes this ability. Alligator serum was found to have antibacterial properties against selected pathogens; however, no study has yet been performed on the antibacterial property of crocodile serum.
There are two species existing in the Philippines, the saltwater crocodile (Crocodylus porosus) and the Philippine freshwater crocodile (Crocodylus mindorensis).
This study explores the antibacterial property of the serum of captive saltwater and Philippine freshwater crocodiles, at different growth stages (juvenile, sub-adult, adult) on human pathogens Enterobacter aerogenes, Pseudomonas aeruginosa, Enterococcus faecalis, and Bacillus subtilis.
Kirby-Bauer Disk Diffusion Method was used and the mean zones of inhibition were measured in millimeters.
It was found that the sera of the two crocodile species at different growth stages exhibited antibacterial property.
Statistical analysis (One-Way ANOVA and Fisher’s LSD) showed that the sub-adult saltwater crocodile serum has a significantly higher potency than the other two growth stages on E. faecalis (p=0.050, a 0.05). The sub-adult freshwater crocodile serum has a higher potency against P. aeruginosa (p-0.049, a 0.05), E. faecalis (p=0.000, a-0.05) and B. subtilis (p=0.001; q0.05) than the juvenile and adult crocodile sera.
Results of T-test for Independent Means indicated that the sera from sub-adult freshwater crocodiles exhibited greater potency than that of sub-adult saltwater crocodiles against P. aeruginosa (p=0.043, a=0.05) and Bacillus subtilis (p=0.004, a 0.05).