A new isoflavone derivative from Streptomyces sp. YIM GS3536

Abstract

1 exhibited appreciable cytotoxicity against human melanoma cell lines (B16) and human leukemia cell lines (HL60) with IC 50 values of 17.5 and 19.2 PM, respectively. The MIC values of 1 for Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Candida albicans were in the range of 23-35 PM.Isoflavone intake from soy-based foods reduces the risk factors for cardiovascular disease and hormone-dependent cancers [1][2][3][4]. Streptomycetes are capable of biotransformation of soybean meal as major organic medium components and production of various isoflavones [5][6][7][8][9][10][11][12][13][14][15]. In our search for new metabolites from actinomycetes, a new compound, 7-O-methyl-8-chlorogenistein (1), together with eight known isoflavones, 8-chlorogenistein (2) [10], kakkatin (3) [7], 7-O-methyl genistein (4) [7], genistein (5) [14], daidzein (6) [7], glycitin (7) [16], genistin (8) [17], and daidzin (9) [18], was isolated from the Streptomyces strain YIM GS3536, which was isolated from soil sample collected from Yunnan Province, P. R. China. In this paper, we report the isolation and full assignment of 1 H and 13 C NMR chemical shifts for these compounds, and the biological activity of 1.The total methanol extract of the culture filtrate was chromatographed on silica gel using a gradient from chloroform to methanol, then on Sephadex LH-20 in methanol, to afford compounds 1-9.Compound 1 was obtained as pale yellow needles. Analysis of the low-resolution mass spectrum of compound 1 showed a characteristic [M + H + 2] + peak (m/z 321) indicative of the presence of a chlorine atom. Its molecular formula was deduced to be C 16 H 11 ClO 5 based on HR-ESI-MS ([M + H] + 319.0377, calcd 319.0373) and 13 C NMR data. O OH O R 1 R 2 R 3 R 4 1' 5' 3' 4 2 8 6 -9A C B 1: R 1 = OH, R 2 = H, R 3 = OCH 3 , R 4 = Cl; 2: R 1 = R 3 = OH, R 2 = H, R 4 = Cl 3: R 1 = R 4 = H, R 2 = OH, R 3 = OCH 3 ; 4: R 1 = OH, R 2 = R 4 = H, R 3 = OCH 3 5: R 1 = R 3 = OH, R 2 = R 4 = H; 6: R 1 = R 2 = R 4 = H, R 3 = OH 7: R 1 = R 4 = H, R 2 = OCH 3 , R 3 = O-Glc; 8: R 1 = OH, R 2 = R 4 = H, R 3 = O-Glc 9: R 1 = R 2 = R 4 = H, R 3 = O-Glc

Engineering a Carbohydrate-processing Transglycosidase into Glycosyltransferase for Natural Product Glycodiversification

“…The J value (<6 Hz) of the anomer of the sugar moiety indicated the α-orientation at the anomeric center of the d -glucopyranosyl unit. The 13 C NMR data of G1 ( Table S2 ) were in good consistent with those of genistin 43 . In the HMBC spectrum of G1, the anomeric proton signal of glucopyranosyl unit at δ H 6.29 correlated with δ C 164.2, indicating that the glucopyranosyl unit was attached to the hydroxyl of the aglycone C-7.…”

Antibacterial and cytotoxic activities of phenolic constituents from the stem extracts of Spatholobus parviflorus

“…The dried stems of S. parviflorus were extracted with acetone and the crude extract was separated by column chromatography which led to the isolation of a new 2-arylbenzofuran, spathobenzofuran (1), and ten known compounds; vignafuran (2) (Csékei et al 2008), lyratin B (3) (Zhang et al 2010), (6aR, 11aR)-medicarpin (4) (Yoon et al 2016), phaseollidin (5) (Dagne et al 1993), daidzein (6) (Takeya and Itokawa 1982), formononetine (7) (Granados-Covarrubias and Maldonado 2009), genistein (8) (Huang et al 2013), 3´-methoxydaidzein (9) (Goto et al 2009), 8-O-methylretusin (10) (Mizuno et al 1990) and 7,3´-dihydroxy-8,4´-dimethoxyisoflavone (11) (Puebla et al 2010) as shown in Figure 1. The structures of all isolated compounds were elucidated by spectroscopic methods, especially 1D and 2D NMR spectroscopy, mass spectrometry and physical data.…”

Bio-Guided Isolation of Antimalarial Metabolites from the Coculture of Two Red Sea Sponge-Derived Actinokineospora and Rhodococcus spp.

“…Moreover, it was discovered in another terrestrial Streptomyces sp. GW39/1530 [28,29]. Furthermore, the molecular formula C9H9NO3 was dereplicated as erbstatin, a simple dehydrotyrosine derivative isolated from Streptomyces amnkusaensis [30,31].…”