Table 1.

Raman peak positions detected in bio-film sample

Culture media (sample)	Raman peak positions detected in sample* (cm−1)	Assigned iron oxides/hydroxides**
Adler medium (AM)	221, 254, 312, 350, 381,465, 530, 650 (Fig. 10a)	lepidocrocite (γ-FeOOH)
	310, 540, 670 (Fig. 10b)	magnetite (Fe3O4)

^*The prominent peak positions in the Raman signals detected are shown in bold

^**The assignment of spectra is on the basis of literature data [38–44]. Since, to the best of our knowledge, Raman studies on biogenic material have not been performed before, the comparison was made with data for natural and synthetic minerals, corrosion products, etc