Apocrine Sweat Gland Bacteria
Denise Hershman
BIOL 224-003
Dr. Russell Grahn
April 15, 2014

This study will determine if the bacteria found in the auxillae can establish puberty. This study will also determine what phylogeny of bacteria is present in the auxillae and what cleaning and deodorizing agents those bacteria are susceptible. It is hypothesized that Staphylococcus bacteria will be present in the auxillae and only if the subject is in puberty or past puberty. It is expected that the Staphylococcus will be susceptible to underarm deodorants, deodorant soaps, and all of the detergents.
Apocrine sweat glands are glands that become active with puberty. Apocrine sweat glands produce merocrine secretions. These secretions are a nutrient source for bacteria. When the bacteria feed on the the secretions, their by-product creates the pungent smell known as body odor. These glands produce feramones that only occur after puberty has begun (Martin, 2012). This study will determine what bacteria are present before and after puberty. This question was posed after learning that the secretions are a food source for bacteria. The apocrine sweat glands only become active after puberty; therefor the bacteria that feed on their secretions could not grow before puberty. A prepubescent female, a pubescent female, a grown male, and a grown female will be the subjects used for this study. Subject one is a female 9 years of age and puberty has not been established. Subject two is a female 12 years of age and puberty is established. Subject three is a male 35 years of age. Subject four is a female 35 years of age. A control of C. pneumonia and S. aureus will be used for each step in this study. A gram stain, a Staphylococcus selective growth test, and a resistance test will be done in this study.
Four subjects were cultured using cotton tipped applicators. The auxillae were cleaned of any deodorants and allowed to rest for 10 hours. The cotton tipped applicators were vigorously rubbed against the epidermis of the auxillae. Each sample was then gram stained along with the control. One agar plate each of Mannitol salt agar (MSA) and Phenylethyl Alcohol Agar (PEA) were acquired. Each plate was labeled with its name and the date. The plates were then split into four sections labeled Aux1, Aux 2, Aux 3, and Aux 4. Each section was inoculated with the coordinating cotton swab. The plates were then incubated at 37oC for 48 hours. The plates were then removed and careful observations and conclusions were made. The largest of the two colonies that grew was sampled and gram stained along with the control to confirm the phylogeny. Observations and drawings were made. The largest colony was sampled and inoculated into a broth medium. The broth was then incubated for 120 hours at 370C. The broth was then removed and gram stained along with the control to confirm aseptic culturing. Two plates of PEA were acquired. Using a pipet, a drop of the broth was placed on each plate. The broth was then spread over the surface of the plate using a lawn technique. Filter papers of Irish Spring Deodorant Soap, Ivory Soap, perfumed body wash, Degree deodorant (18.2% aluminum zirconium tetrachlorohydex), Dove deodorant (15.2% aluminum zirconium tetrachlorohydex), and Old Spice deodorant (dipropylene glycol, sodium stearate, PPG-3 myristyl ehter, tretra sodium EDTA) were placed on the surface of one plate and labeled 1-6. Filter papers of Arm & Hammer laundry detergent, distilled vinegar, Dawn dish soap, ammonia, sodium carbonate, and bleach were placed on the surface of the second plate and labeled 7-12. The plates were then incubated at 37oC for 48 hours. The plates were then removed and careful observations and conclusions were made.
The initial gram stain showed both gram-positive and gram-negative bacteria in all the samples (Figure 1). The growth on the MSA and PEA appeared on Aux 2, Aux 3, and Aux 4, but not on Aux 1 (Figure 2). The growth