Study of the invasion of human hair in vitro by Aphanoascus spp.

The course of the destruction of human hair in vitro by three species of the genus Aphanoascus (A. keratinophilus, A. fulvescens and A. verrucosus) was studied with light microscopy, and transmission and scanning electron microscopy. The results obtained show that all the three species develop keratinolytic activity. A. fulvescens and A. verrucosus have similar sequences of degradation, invading the hair through the cuticula, but without the presence of specialized erosive organs. A. keratinophilus, however, shows a different way of invasion, and the keratinolytic activity was mainly located in the cortex and from that point on expanded to the cuticula.