title: The antimicrobial effect of narrow-band UVB (313 nm) and UVA1 (345-440 nm) radiation in vitro.
abstract: Two new UV lamps were investigated with respect to their antibacterial effectiveness in vitro. Propioni (n = 20 strains) and Micrococcaceae (n = 16 strains) bacteria extracted from acne patients were applied to RCM and sheep blood agar plates and irradiated with a narrow-band UVB lamp (TL 100W/10R) at a wavelength of 313 nm and a UVA1 lamp (TL 01) at a wavelength of 345-440 nm. The precisely defined energy levels were, in the case of narrow-band UVB, 0.00, 0.30, 0.50, 1.00, 2.00 and 3.00 J/cm2 and, in the case of UVA1, 0.00, 2.50, 5.00, 7.50, 10.00 and 20.00 J/cm2. UVA1 inhibited neither the growth of Propioni nor Micrococcaceae bacteria. In contrast, the growth of Micrococcaceae was inhibited already at a dosage of 0.30 J/cm2 of narrow-band UVB (P < 0.05), highly significant from 0.50 J/cm2 (P < 0.01) and to a maximum of 2.2 powers of 10 at 3.00 J/cm2 compared with non-radiated control plates. Propioni bacteria were significantly inhibited at the minimum dosage of 0.30 J/cm2 of narrow-band UVB (P < 0.01) and to a maximum of 2.8 powers of 10 at 3.00 J/cm2.
authors.affiliation: Dermatological Department, Clinical Centre of Karlsruhe, Germany.
authors.forename: J W
authors.initials: JW
authors.lastname: Fluhr
authors.forename: M
authors.initials: M
authors.lastname: Gloor
mesh_terms: D000152:Acne Vulgaris / Q000382:microbiology; D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008835:Micrococcaceae / Q000254:growth & development / Q000528:radiation effects*; D011424:Propionibacterium / Q000254:growth & development / Q000528:radiation effects*; D014466:Ultraviolet Rays