Publications by authors named "G B. Elyakov"
Aims: This study aims at evaluating the impact of the nutrient medium components on the in vitro production of the cytotoxic alterochromides.
Methods And Results: The employment matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) facilitated the identification of a range of brominated cyclic depsipeptides with molecular masses of 843/845, 857/859 and 922/924/926 Da, and 936/938/940 Da produced by the marine bacterium Pseudoalteromonas maricaloris KMM 636T. The fractions of cytotoxic yellow pigments yielded after methanol extraction of P.
Four new diterpene glycosides, virescenosides R (1), S (2), T (3), and U (4), have been isolated from a marine strain of Acremonium striatisporum KMM 4401 associated with the holothurian Eupentacta fraudatrix. Their structures have been elucidated on the basis of HRFABMS, 1D and 2D NMR (1H, 13C, DEPT, COSY-45, COSY-RCT, HSQC, HMBC, and NOESY spectra), and the results of acidic hydrolysis as 19-O-[beta-D-glucopyranosyl(1-->6)-beta-d-altropyranosyl]-isopimara-7,15-diene-2alpha,3beta-diol (1), 19-O-beta-D-altropyranosyl-3-oxo-isopimara-8(14),15-diene-7alpha-ol (2), 19-O-beta-D-altropyranosyl-3,7-dioxo-isopimara-8,15-diene (3), and 19-O-beta-D-altropyranosyl-3,7-dioxo-isopimara-8(14),15-diene (4). The cytotoxic activity of the virescenosides was examined.
View Article and Find Full Text PDFThree new diterpene glycosides, virescenosides O (1), P (2), and Q (3), have been isolated from a marine strain of Acremonium striatisporum KMM 4401 associated with the holothurian Eupentacta fraudatrix. Their structures were determined on the basis of HRMALDIMS and NMR data as beta-D-altropyranosido-19-isopimara-8(14),15-diene-7alpha,3beta-diol (1), beta-D-altropyranosido-19-7-oxoisopimara-8(9),15-diene-3beta-ol (2), and beta-D-mannopyranosido-19-isopimara-7,15-diene-3beta-ol (3). The cytotoxic activity of the virescenosides was examined.
View Article and Find Full Text PDF