title: New spirotetronate antibiotics, lobophorins H and I, from a South China Sea-derived Streptomyces sp. 12A35.
abstract: Strain 12A35 was isolated from a deep-sea sediment collected from the South China Sea and showed promising antibacterial activities. It was identified as Streptomyces sp. by the 16S rDNA sequence analysis. Bioassay-guided fractionation using HP20 adsorption, flash chromatography over silica gel and octadecylsilyl (ODS) and semi-preparative HPLC, led to the isolation and purification of five metabolites from the fermentation culture of 12A35. Two new spirotetronate antibiotics, lobophorins H (1) and I (2), along with three known analogues, O-β-kijanosyl-(1→17)-kijanolide (3), lobophorins B (4) and F (5) were characterized by 1D, 2D-NMR and MS data. These compounds exhibited significant inhibitory activities against Bacillus subtilis. Compounds 1 and 5 exhibited moderate activities against Staphylococcus aureus. In particular, the new compound lobophorin H (1) showed similar antibacterial activities against B. subtilis CMCC63501 to ampicillin.
authors.affiliation: Department of Natural Products Chemistry, Shenyang Pharmaceutical University, Shenyang 110016, China. huimhua@163.com.
authors.forename: Hua-Qi
authors.initials: HQ
authors.lastname: Pan
authors.forename: Song-Ya
authors.initials: SY
authors.lastname: Zhang
authors.forename: Nan
authors.initials: N
authors.lastname: Wang
authors.forename: Zhan-Lin
authors.initials: ZL
authors.lastname: Li
authors.forename: Hui-Ming
authors.initials: HM
authors.lastname: Hua
authors.forename: Jiang-Chun
authors.initials: JC
authors.lastname: Hu
authors.forename: Shu-Jin
authors.initials: SJ
authors.lastname: Wang
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects; D002681:China; D019015:Geologic Sediments / Q000382:microbiology; D018942:Macrolides / Q000737:chemistry* / Q000494:pharmacology*; D009792:Oceans and Seas; D013211:Staphylococcus aureus / Q000187:drug effects; D013302:Streptomyces / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D018942:Macrolides