The diversity and abundance of fungi and bacteria on the healthy and dandruff affected human scalp

PLoS One. 2019 Dec 18;14(12):e0225796. doi: 10.1371/journal.pone.0225796. eCollection 2019.

Abstract

Dandruff is a skin condition that affects the scalp of up to half the world's population, it is characterised by an itchy, flaky scalp and is associated with colonisation of the skin by Malassezia spp. Management of this condition is typically via antifungal therapies, however the precise role of microbes in the aggravation of the condition are incompletely characterised. Here, a combination of 454 sequencing and qPCR techniques were used to compare the scalp microbiota of dandruff and non-dandruff affected Chinese subjects. Based on 454 sequencing of the scalp microbiome, the two most abundant bacterial genera found on the scalp surface were Cutibacterium (formerly Propionibacterium) and Staphylococcus, while Malassezia was the main fungal inhabitant. Quantitative PCR (qPCR) analysis of four scalp taxa (M. restricta, M. globosa, C. acnes and Staphylococcus spp.) believed to represent the bulk of the overall population was additionally carried out. Metataxonomic and qPCR analyses were performed on healthy and lesional buffer scrub samples to facilitate assessment of whether the scalp condition is associated with differential microbial communities on the sampled skin. Dandruff was associated with greater frequencies of M. restricta and Staphylococcus spp. compared with the healthy population (p<0.05). Analysis also revealed the presence of an unclassified fungal taxon that could represent a novel Malassezia species.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • China
  • Dandruff* / epidemiology
  • Dandruff* / microbiology
  • Dermatomycoses / microbiology*
  • Female
  • Humans
  • Malassezia* / classification
  • Malassezia* / isolation & purification
  • Male
  • Microbiota*
  • Middle Aged
  • Propionibacteriaceae / isolation & purification
  • Scalp / microbiology*
  • Skin / microbiology*
  • Staphylococcus / isolation & purification
  • Young Adult

Grants and funding

This work was funded by Unilever Research and Development. Sally Grimshaw, Adrian M. Smith, David S. Arnold, Elaine Xu, Michael Hoptroff, Barry Murphy, Yishu Huang, Fiona Baines and Shengjun Lou contributed to/or conducted the study while employed by Unilever. The funder provided support in the form of salaries for authors [SG, AMS, DSA, EX, MH and BM], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.