Heterologous production and characterization of a pyomelanin of Antarctic Pseudomonas sp. ANT_H4: a metabolite protecting against UV and free radicals, interacting with iron from minerals and exhibiting priming properties toward plant hairy roots.

Background: Antarctica has one of the most extreme environments in the world. This region is inhabited by specifically adapted microorganisms that produce various unique secondary metabolites (e.g.

A new kaempferol diglycoside from Datura suaveolens Humb. & Bonpl. ex. Willd.

A new flavonol glycoside, kaempferol 3-O-alpha-L-arabinopyranosyl-7-O-beta-D-glucopyranoside (1), has been isolated from methanol extract of leaves of Datura suaveolens (Solanaceae), along with six other known compounds, which include kaempferol 3-O-alpha-L-arabinopyranoside (2), 3-phenyl lactic acid, 3-(3-indolyl) lactic acid, and its methyl ester, physalindicanol A and physalindicanol B. The structural elucidation of 1 and characterization of the known compounds are based on detailed spectral analysis (ESI-FTICR-MS and 2D-NMR). This is the first report of isolation of these compounds from this plant.

Hyosgerin, a new optically active coumarinolignan, from the seeds of Hyoscyamus niger.

Hyosgerin, a new optically active coumarinolignan, has been isolated and characterized along with three other coumarinolignans, venkatasin, cleomiscosin A and cleomiscosin B, from the seeds of Hyoscyamus niger L. The structure was determined on the basis of spectroscopic analysis and chemical conversion. The optical properties and absolute stereochemistry of these coumarinolignans have also been studied and discussed.

Serum amyloid A-derived peptides, present in human rheumatic synovial fluids, induce the secretion of interferon-gamma by human CD(4)(+) T-lymphocytes.

Serum amyloid A (SAA) is a major acute-phase protein whose biochemical functions remain largely obscure. Human rheumatic synovial fluids were screened by high performance liquid chromatography mass spectrometry for SAA-derived peptides, specifically the sequence AGLPEKY (SAA(98-104)) which was previously shown to modulate various leukocyte functions. Two such fluids were found to contain a truncated version of SAA(98-104).

Mutagenic effect of 1.1'-hexamethylene-bis-[(5-p-chlorophenyl)-biguanide].

The strongly effective bactericidal compound 1.1'-hexamethylene-bis-[(5-p-chlorophenyl)-biguanide] (HCG) induces mutations with a slight inactivation rate in the auxotrophic strains Salmonella typhimurium TA 1535 and TA 1538 in 0.4 microM solution.