Fractionation and Peptide Analysis of Hair

Complete chemical analysis of the medulla of human hair fibers has not been reported. Studies of the medulla of human hair are complicated because it has poor solubility and is difficult to isolate. In fact, most of the experimental work on medulla has been on African porcupine quill, horse hair, or goat hair medulla rather than medulla of human hair fiber. Rogers [66] has described the amino acid composition of medullary protein isolated from porcupine quill, and his results are summarized in Table 2-7. 

Blackburn [88] has also determined some of the amino acids from medulla of wool fibers. Most wool fibers do not contain a medulla however, some coarse wools like kemp do contain this porous component. Although Blackburn s results are more qualitative, they agree in general with the data of Rogers, suggesting a low cystine content when compared to whole fiber, as well as relatively large amounts of acidic and basic amino acids. The low cystine content of medullary protein is consistent with its low sulfur content [89]. 

Fractionation and Peptide Analysis of Hair N-Terminal Amino Acids 

Kerr and Godin [90], using the dinitrophenylation method of Sanger [91], have identified valine, threonine, glycine, alanine, serine, glutamic acid, and aspartic acid as N-terminal amino acids in human hair. Quantitative data 

Amino acids [tmol/g hair Reference 64 Reference 7 

---