RESUMEN
Structural peculiarities of low molecular weight (LMW) sample obtained by mild acid hydrolysis of κ-carrageenan from Chondrus armatus was investigated by a rapid mass spectrometric method. The selected conditions allowed avoiding excess destruction of 3,6-AnGal residues that was shown by using tandem (MS/MS) mode. Main oligosaccharide fraction with molecular weight 2.3 kg/mol, obtained by mild acid hydrolysis was chosen for the analysis. It was shown that fragments with even degree of polymerization (DP) were mostly built of (-G4S-DA-)n repeating unit, n=1-5. Some fragments with odd DP were shown to contain -DA2S- insertions, being the fragments of ι-type blocks, which were randomly distributed along the polysaccharide chain as single insertions. The anti-inflammatory activity (on acetic acid-induced colitis in mice) of the initial polymer and its derivatives was studied. The anti-inflammatory effect of the polymer was observed at a dose of 5mg/kg. Polysaccharide decreased the degree of colon damage more than twice and area of damage in 40%.
Asunto(s)
Antiinflamatorios , Carragenina , Chondrus , Colitis/tratamiento farmacológico , Oligosacáridos , Ácido Acético , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Carragenina/química , Carragenina/farmacología , Carragenina/uso terapéutico , Colitis/inducido químicamente , Colitis/enzimología , Colitis/patología , Colon/efectos de los fármacos , Colon/enzimología , Colon/patología , Geles , Hidrólisis , Masculino , Ratones , Peso Molecular , Oligosacáridos/química , Oligosacáridos/farmacología , Oligosacáridos/uso terapéutico , Peroxidasa/metabolismo , Espectrometría de Masas en TándemRESUMEN
Six new highly oxygenated chromene derivatives, oxirapentyns F-K (2-7), one new polyketide (8), one new benzofurane (9), and two known cyclodepsipeptides, isoisariin B and isaridin E, were isolated from the lipophilic extract of the marine-derived fungus Isaria felina KMM 4639. The structures of compounds 2-9 were determined using spectroscopic methods. The relative configurations of compounds 2-7 were established through a combination of NOE data and spin coupling constants, and these results were confirmed by X-ray crystallographic analysis of 4. The absolute structures of all oxirapentyns were assumed based on their biogenetic relationship and confirmed using the modified Mosher's method on 2 and 7. Isariketide (8) showed moderate cytotoxicity toward HL-60 cells.