Q-312. A Study on Fractal Morphogenesis in Bacteria as an Adaptive Response to Environmental Stress

H. E. Woriax, M. E. Santos;
Univ. of North Carolina, Pembroke, NC.

This study was conducted as an experimental investigation of the effect of herbal mixtures and diffusion-limited agar media on formation of fractal morphology in bacteria. Actively growing gram positive Micrococcus luteus and gram negative Escherichia coli were surface plated on standard LB agar, 8% soft LB agar, 17% hard LB agar, standard LB agar + garlic, LB agar + golden seal and LB agar + sage and on the selective differential media mannitol salt agar and eosin methylene blue agar for 24 to 48 hours at 25°C and 37°C, respectively. Non - fractal colonies were established to be in the 0.1 to 1.0 mm size while fractal colonies were in the 3.0 to 7.5 mm size. Garlic, sage and golden seal promoted fractal growth in soft and hard agar, yielding more fractal colonies in hard agar than soft agar. Thus, the hardness of the agar limited the diffusion of nutrients and encouraged fractal morphogenesis. Garlic obliterated 100% of E. coli at 24 hrs and 50% of M. luteus at 24 hrs on all media. The degree of bacterial death for sage and golden seal was less than 50% for E. coli and M. luteus at 24 hrs and 48 hrs, respectively, on all media. Surviving colonies exhibited more fractal colonies than non-fractal colonies. Fractal colonies remained viable after 30 days. The presence of herbal mixtures and the use of diffusion-limited culture media promoted fractal morphogenesis in bacteria as an adaptive response to a non-equilibrium environment.