2006 ANNUAL SCIENTIFIC MEETING 183 3. Low molecular weight zirconium polymer distributions in AZG actives result in increased efficacy and is the single most important criteria for achieving superior efficacy. 4. Zirconium polymerization can easily occur during manufacturing and must be controlled in order to maintain low molecular weight zirconium polymer distributions necessary for superior efficacy. Factors to consider are choice of zirconium starting materials, preparation of the zirconium­ glycine component, mixing of the aluminum and zirconium-glycine components and spray drying parameters. Proprietary processing techniques have been developed to address the above findings. Some of these are as follows: 1. A unique, cost-effective activation process resulting in actives containing large amounts of the peak 4 aluminum polymer. 2. Minimal contact time between the aluminum and zirconium-glycine reactant components before spray drying to the final AZG powder product. In addition to chemical considerations, there are other properties of the actives which are important in formulating the final antiperspirant product. Particle size and shape of powder actives vary depending upon the dosage form in question. For aerosol products particle size is selected to minimize valve and actuator clogging. Both milled and spherical particle actives are used. For sticks and soft solid applications a much finer particle size is normally used compared to aerosol products. The main considerations for these products are application, feel and low residue properties. In combination with good masking agents, spherical particle actives have somewhat better low residue properties than milled particle actives. Also spherical actives provide better glide-on properties during product application. Liquid actives are used in aqueous based roll-ons, gels, and creams. For these dosage forms concentration, color, clarity and refractive index are important factors for formulating these products. Liquid actives are usually available at 35% and 45-50% (by weight) concentration. The higher concentration actives offer added flexibility to the formulator. Color and clarity are important for clear roll-on and gel applications. Refractive index of the active must be such that matching the refractive index of the oil and aqueous phases of clear gel products is easily accomplished.

184 JOURNAL OF COSMETIC SCIENCE ANTIMICROBIAL COMPOUNDS (AMC'sJ AS INHIBITORS OF BACTERIAL GROWTH CAUSING SWEAT MALODOR Nava Dayan 1, Ph.D., Philip Wertz2, Ph.D. and D. Drake2 1 Lipo Chemicals, Inc., Paterson, NJ, 07504 2 Dows Institute N450 DSB, University of Iowa, Iowa City, IA 52242 Introduction Over the past decade the anti-perspirant and deodorant market, have shown a very mild steady growth of about 0.3% a year. While companies search for the breakthrough in innovation they mostly focus on expending their existing lines and pursuing different marketing approaches such as gender and age segmentation (1). Others upscale their products by incorporating pro-vitamins and improve skin smoothness, or prolong odor control by using a delivery system. Interestingly, in 2005 Kao Brands launched a new product based on a patented technology using phellodendron plant extract to inhibit sweat bacterial degradation that is known to cause malodor (2). Sweating is known to assist with regulation of body temperature and skin moisturization. It was also shown to contain natural antibiotics, dermicidins, to protect the skin. It does, however, generate undesired malodor that is believed to be caused by the degradation of sweat component by enzymes released from the Corynebacterium species (3 ). While deodorants are limited in masking the odor, antiperspirants possess even bigger concerns. They are associated with safety issues related to the absorption of aluminum species into and through the skin that may cause topical disorders such as contact dermatitis or systemic disorders such as Alzheimer's disease and breast cancer (4). We suggest a novel approach for growth inhibition of the malodor causing bacteria. A group of compounds isolated from human skin, AMC' s, were shown to inhibit bacterial growth and are believed to be the natural controlling elements for bacterial growth in the skin. The data presented and future studies are designed to evaluate the effectiveness of AMC's on microbial species as an approach to control malodor. Methodology Isolation of AMC' s from the skin AMC's were collected from skin surface of the arms and legs of human volunteers, fractionated by preparative TLC and tested. Antimicrobial testing The anti-microbial activity of AMC's was tested against strains of Staphylococci and Corynehacterium. The growth inhibitory activity of a range of different AMC concentrations were tested as well as correlation between 'activity and chain length of AMC' s. The methodology was adapted from Lambert and Pearson (5). The bacteria were cultured in Brain Heart Infusion Broth (BHIB) for 24 hours. The cells were isolated via centrifugation and then suspended in BHIB. Assays were done in standard micro-liter plates. The bacterial suspensions were diluted to concentration of 5x105 cfu/mJ and standardized at an absorbance of 660 nm. The growth inhibitory activity was assessed at 2-hour intervals for 12 hours. At 24 hours, an automated micro-liter plate reader assessed the growth inhibitory activity. The growth inhibitory activity of the lipids was measured using the area of an absorbance/time curve in comparison to a control. Minimum and non-inhibitory concentration values were determined. Experiments were performed at a minimum of three times to assess variability of the MIC and NIC values from experiment to experiment. Preliminary Results The different fractions isolated from the skin. included compounds with different chain lengths and polarities. In the absence of AMC' s, an initial CFU/mJ of I 06 had increased to I 011 or 2 orders of magnitude during incubation of Staphylococcus aure�s. Fraction #1 of AMC's slightly enhanced bacterial growth, possibly by serving as a nutrient. Fractions 2 and 3 had no effect on growth, and fractions 4 and 5 demonstrated significant growth inhibition, with#4 being the most potent one (Figure 1).