Environmental and Industrial Microbiology Consulting
Report for UV Technologies on Bacterial Plating Experiment
Sara Silverstone, Ph.D.
November 6, 2012
A swab sample was taken on human skin and inside the nasal passage. Skin and nasal passage
was treated with UV light and swab sampling repeated. All samples were grown on nutrient agar.
Plates were sent to a certified environmental testing laboratory for identification of bacteria.
All 4 plates had 3 genera of bacteria: Micrococcus, Staphylococcus and Bacillus. In addition, the
nostril control has one colony of Cladosporium; a common environmental mold and a tiny pink
colony of yeast. The yellow colonies on each plate is Micrococcus, a common skin microbe. The
smaller white colonies are coagulase-negative Staphylococcus. The most common type is
Staphyloccus epidermidis, and like Micrococcus, these are normal and harmless skin bacteria.
Although a single pair of samples is not significant, it appears there are slightly more Bacillus on
the U-V treated nostril plates and many more Staphylococcus on the nostril control. There is also
the presence of a large, spreading Bacillus on the hand control and two fungal colonies on the
nostril control, which are not present on the UV-treated plates. (see figures).
Bacillus are Gram-positive, endospore-forming rod-shaped bacteria that normally live n soil but
are fairly ubiquitous in the environment.
Micrococcus are yellow-colored Gram-positive spherical-shaped bacteria that live on human skin,
in soil, dust and other environments. They are not considered to be pathogens, but rather, are
normal skin flora.
Staphylococcus are Gram-positive spherical bacteria that grow in clusters. Under the microscope,
they appear like bunches of purple grapes. There are 33 species of Staphylococcus which normal
human flora, found on the skin and the nasal cavity. One species, Staphylocccus aureus, is normal
flora on 25% of people, however, it can cause infections in healthy people if it gets into a break
in the skin. In fact, S. aureus has developed that is resistant to common antibiotics (MRSA or
multidrug-resistant Staphyloccus aureus) and responsible for dangerous and difficult to treat
infections. MRSA are of particular concern in hospitals, and nursing homes, where patients with
open wounds, invasive devices, and weakened immune systems are at greater risk
of infection than the general public.
The species of Staphylococcus observed in this study was not identified to species, except that S.
aureus or other coagulase-positive species were ruled out. Staphylococcus epidermidis is not pathogenic on normal healthy people, however it can cause infections associated with indwelling
biomaterials (e.g., catheters and prostheses).
While it is difficult to tell from the few samples and photos available, it appears likely that
Staphylococcus colonies are more common in control samples than in UV-treated samples.
Because MRSA cannot be treated with antibiotics, there is a need for alternative treatments for
these resistant Staph infections. If UV Technologies product(s) can kill Staphylococcus in/on the
human body, then this would represent a powerful new tool to fight MRSA.