Chlokamycin, a New Chloride from the Marine-derived Streptomyces sp. MA2-12

A new chlorinated metabolite designated chlokamycin (1), was isolated along with ikarugamycin (2) from the culture broth of the marine-derived Streptomyces sp. MA2–12. The structure of 1 was elucidated based on spectroscopic analyses (1D and 2D NMR data and ROESY correlations). Chlokamycin moderately inhibited the growth of Jurkat cells and HCT116 cells with IC50 values of 24.7 and 33.5 μM, respectively.

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Flavonoids from Curcuma longa Leaves and their NMR Assignments

Natural Product Communications ◽

10.1177/1934578x1501000117 ◽

2015 ◽

Vol 10 (1) ◽

pp. 1934578X1501000 ◽

Cited By ~ 1

Author(s):

Chia-Ling Jiang ◽

Sheng-Fa Tsai ◽

Shoei-Sheng Lee

Keyword(s):

Nmr Assignments ◽

Soluble Fraction ◽

Curcuma Longa ◽

2D Nmr ◽

Etoh Extract ◽

Spectroscopic Analyses ◽

Nmr Data ◽

The Common ◽

Reported Data ◽

C Nmr

Chemical investigation of the n-BuOH-soluble fraction of the EtOH extract of the aerial part of Curcuma longa led to the isolation of 11 flavonol glycosides and one dihydroflavonol glucoside (1) via chromatography over Sephadex LH-20 and Lobar RP-18 columns. Although they are known, the 1H and 13C NMR data recorded in CD3OD rather than the common DMSO- d6 are doubly checked via extensive 2D NMR spectroscopic analyses, leading to some revisions of the reported data, especially for the glycon part.

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Isolation, Structure Elucidation and Activity of Anthracycline Acetates from a Terrestrial Streptomyces sp.

Zeitschrift für Naturforschung B ◽

10.1515/znb-2003-1215 ◽

2003 ◽

Vol 58 (12) ◽

pp. 1242-1246 ◽

Cited By ~ 1

Author(s):

Serge Fotso ◽

Rajendra P. Maskey ◽

Iris Grün-Wollny ◽

Hartmut Laatsch

Keyword(s):

Molecular Weight ◽

Natural Product ◽

Structure Elucidation ◽

Ethyl Acetate Extract ◽

2D Nmr ◽

Streptomyces Sp ◽

Naturally Occurring ◽

Nmr Data ◽

New Antibiotics ◽

First Time

The red coloured ethyl acetate extract of the Streptomyces sp. isolate GW37/3236 delivered the two new antibiotics 13-O-acetyl-bisanhydro-13-dihydrodaunomycinone (3c) and 4,13-O-diacetylbisanhydro- 4-O-demethyl-13-dihydrodaunomycinone (3d) and additionally several known compounds. The quinones 3c and 3d are the first naturally occurring quinone acetates. Their structures were derived by comparison of the NMR data with those of bisanhydro-13-dihydrodaunomycinone (3b) and by interpretation of the 2D NMR data accompanied by the molecular weight and formula. 2-Acetamido-3-hydroxybenzamide (5) was also isolated from the extract and was identified by comparison of the NMR data with those of 2-acetamidobenzamide and by 2D NMR correlations. 6,9,11- Trihydroxy-4-methoxy-5,12-naphthacenedione (4) is isolated for the first time as a natural product.

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Novel 1,3-Benzodioxole From Marine-Derived Actinomycete in East Vietnam Sea

Natural Product Communications ◽

10.1177/1934578x20920042 ◽

2020 ◽

Vol 15 (5) ◽

pp. 1934578X2092004

Author(s):

Dao Phi Thi ◽

Huong Doan Thi Mai ◽

Duc Danh Cao ◽

Quyen Vu Thi ◽

Mai Anh Nguyen ◽

...

Keyword(s):

2D Nmr ◽

Culture Broth ◽

Genus Streptomyces ◽

Nmr Data ◽

Actinomycete Strain ◽

Spectral Data Analysis ◽

And Staphylococcus Aureus ◽

16Srrna Gene ◽

Mcf 7 ◽

C Nmr

Analysis of an antimicrobial extract from the culture broth of the marine-derived actinomycete Streptomyces sp. G261 led to the isolation of a new 1,3-benzodioxole derivative (1), together with 10 known compounds 2-11. The actinomycete strain G261 was isolated from sediment, collected at Cu Lao Cham, Quang Nam in Vietnam. The taxonomic identification of the strain G261 was achieved by analysis of 16SrRNA gene sequences. On the basis of morphological and phylogenetic evidence, the actinomycete strain G261 was assigned to the genus Streptomyces. The structures of the isolated compounds were established by their spectral data analysis, including mass spectrometry, 1-dimensional nuclear magnetic resonance (1D-NMR), and 2D-NMR. The structure of 1 was confirmed by comparison of the calculated with experimental 13C NMR data. Compound 1 exhibited antimicrobial activity against Enterococcus faecalis and Staphylococcus aureus with minimum inhibitory concentration values of 128 and 256 µg/mL, respectively. Whereas, compound 1 had a weak inhibition when tested against 4 cancer cell lines, KB, LU-1, HepG-2, and MCF-7.

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Acylated Aminooligosaccharides with Inhibitory Effects against α-Amylase from Streptomyces sp. HO1518

Marine Drugs ◽

10.3390/md16110403 ◽

2018 ◽

Vol 16 (11) ◽

pp. 403 ◽

Cited By ~ 1

Author(s):

Hai-Li Liu ◽

Heng-Chao E ◽

Ding-An Xie ◽

Wen-Bo Cheng ◽

Wan-Qi Tao ◽

...

Keyword(s):

Type Ii Diabetes ◽

Spectroscopic Analysis ◽

2D Nmr ◽

Ionization Mass ◽

Inhibitory Effects ◽

Streptomyces Sp ◽

Nmr Data ◽

New Compounds ◽

Drug Leads ◽

Clinical Drug

Five new acylated aminooligosaccharides (1–5), together with one known related analogue (6), were isolated from Streptomyces sp. HO1518. Their structure was identified by extensive spectroscopic analysis, including 1D and 2D NMR data and high resolution electrospray ionization mass spectrometry (HRESIMS), and by comparison with those reported in the literature. All of the new compounds showed more promising porcine pancreatic α-amylase (PPA) inhibitory activities than the clinical drug acarbose, indicating them as potential pharmaceutical drug leads toward type II diabetes.

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Secondary Metabolites from an Actinomycete from Vietnam's East Sea

Natural Product Communications ◽

10.1177/1934578x1601100320 ◽

2016 ◽

Vol 11 (3) ◽

pp. 1934578X1601100 ◽

Cited By ~ 3

Author(s):

Quyen Vu Thi ◽

Van Hieu Tran ◽

Huong Doan Thi Mai ◽

Cong Vinh Le ◽

Minh Le Thi Hong ◽

...

Keyword(s):

Antimicrobial Activity ◽

Cell Lines ◽

2D Nmr ◽

Culture Broth ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Nmr Data ◽

Clinically Significant ◽

First Time ◽

Mcf 7

Analysis of an antimicrobial extract prepared from culture broth of the marine-derived actinomycete Nocardiopsis sp. (strain G057) led to the isolation of twelve compounds, 1–12. Compound 1 (2-[(2 R-hydroxypropanoyl)amino]benzamide) was found to be a new enantiomeric isomer while compounds 2 (3-acetyl-4-hydroxycinnoline) and 3 (3,3′-bis-indole) were isolated from a natural source for the first time. The structures of 1 – 12 were determined by analyses of MS and 2D NMR data. All compounds were evaluated for their antimicrobial activity against a panel of clinically significant microorganisms. Compound 1 selectively inhibited Escherichia coli (MIC: 16 μg/mL). Compounds 2 and 3 exhibited antimicrobial activity against several strains of both Gram-positive and Gram-negative bacteria, and the yeast Candida albicans. Cytotoxic evaluation of compounds 1 – 3 against four cancer cell lines (KB, LU-1, HepG-2 and MCF-7) indicated that compound 3 produced a weak inhibition against KB and LU cell lines. Two remaining compounds, 1 and 2 were not cytotoxic, even at the concentration of 128 μg/mL.

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Phenolic Constituents of Carex vulpinoidea Seeds and their Tyrosinase Inhibitory Activities

Natural Product Communications ◽

10.1177/1934578x1501000328 ◽

2015 ◽

Vol 10 (3) ◽

pp. 1934578X1501000 ◽

Cited By ~ 1

Author(s):

Daniel B. Niesen ◽

Hang Ma ◽

Tao Yuan ◽

Alvin C. Bach ◽

Geneive E. Henry ◽

...

Keyword(s):

2D Nmr ◽

Spectroscopic Analyses ◽

Nmr Data ◽

Phenolic Constituents ◽

Inhibitory Activities ◽

Tyrosinase Enzyme

Two new phenolics, a stilbenoid, vulpinoideol A (1), and a chalcone, vulpinoideol B (2), along with ten known compounds (3–12) were isolated from Carex vulpinoidea Michx. seeds. The structures of compounds 1–12 were elucidated based on spectrometric and spectroscopic analyses including HRESIMS, 1D and 2D NMR data. All compounds were evaluated for their tyrosinase enzyme inhibitory activities.

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Targeted Isolation of Xenicane Diterpenoids from Taiwanese Soft Coral Asterospicularia laurae

Marine Drugs ◽

10.3390/md19030123 ◽

2021 ◽

Vol 19 (3) ◽

pp. 123

Author(s):

Yu-Chi Lin ◽

Yi-Jen Chen ◽

Shu-Rong Chen ◽

Wan-Ju Lien ◽

Hsueh-Wei Chang ◽

...

Keyword(s):

Cytotoxic Effect ◽

Soft Coral ◽

Ethanol Extract ◽

2D Nmr ◽

Ionization Mass ◽

Spectroscopic Analyses ◽

Potential Source ◽

First Case ◽

The Family ◽

Mcf 7

Application of LC-MS/MS-based molecular networking indicated the ethanol extract of octocoral Asterospicularia laurae is a potential source for the discovery of new xenicane derivatives. A natural product investigation of this soft coral resulted in the isolation of four new xenicane diterpenoids, asterolaurins O‒R (1‒4), together with six known compounds, xeniolide-A (5), isoxeniolide-A (6), xeniolide-B (7), 7,8-epoxyxeniolide-B (8), 7,8-oxido-isoxeniolide-A (9), and 9-hydroxyxeniolide-F (10). The structures of isolated compounds were characterized by employing spectroscopic analyses, including 2D-NMR (COSY, HMQC, HMBC, and NOESY) and high-resolution electrospray ionization mass spectrometry (HRESIMS). Asterolaurin O is the first case of brominated tricarbocyclic type floridicin in the family Xeniidae. Concerning bioactivity, the cytotoxic activity of those isolates was evaluated. As a result, compounds 1 and 2 demonstrated a selective cytotoxic effect against the MCF-7 cell line at IC50 of 14.7 and 25.1 μM, respectively.

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Two New Phomaligols from the Marine-Derived Fungus Aspergillus flocculosus and Their Anti-Neuroinflammatory Activity in BV-2 Microglial Cells

Marine Drugs ◽

10.3390/md19020065 ◽

2021 ◽

Vol 19 (2) ◽

pp. 65

Author(s):

Byeoung-Kyu Choi ◽

Duk-Yeon Cho ◽

Dong-Kug Choi ◽

Phan Thi Hoai Trinh ◽

Hee Jae Shin

Keyword(s):

Nitric Oxide ◽

Mass Spectrometry ◽

Optical Rotation ◽

Chemical Oxidation ◽

Culture Broth ◽

Membered Ring ◽

Microglial Cells ◽

No Production ◽

Nmr Data ◽

Ic50 Value

Two new phomaligols, deketo-phomaligol A (1) and phomaligol E (2), together with six known compounds (3–8) were isolated from the culture broth of the marine-derived fungus Aspergillus flocculosus. Compound 1 was first isolated as a phomaligol derivative possessing a five-membered ring. The structures and absolute configurations of the new phomaligols were determined by detailed analyses of mass spectrometry (MS), nuclear magnetic resonance (NMR) data, optical rotation values and electronic circular dichroism (ECD). In addition, the absolute configurations of the known compounds 3 and 4 were confirmed by chemical oxidation and comparison of optical rotation values. Isolated compounds at a concentration of 100 μM were screened for inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-induced BV-2 microglial cells. Among the compounds, 4 showed moderate anti-neuroinflammatory effects with an IC50 value of 56.6 μM by suppressing the production of pro-inflammatory mediators in activated microglial cells without cytotoxicity.

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Secondary Metabolites with Nitric Oxide Inhibition from Marine-Derived Fungus Alternaria sp. 5102

Marine Drugs ◽

10.3390/md18080426 ◽

2020 ◽

Vol 18 (8) ◽

pp. 426 ◽

Cited By ~ 1

Author(s):

Senhua Chen ◽

Yanlian Deng ◽

Chong Yan ◽

Zhenger Wu ◽

Heng Guo ◽

...

Keyword(s):

Secondary Metabolites ◽

2D Nmr ◽

X Ray ◽

X Ray Crystallography ◽

Spectroscopic Analyses ◽

Structure Activity ◽

Ic50 Values ◽

Alternaria Sp ◽

Modified Mosher’S Method ◽

Oxide Inhibition

Two new benzofurans, alternabenzofurans A and B (1 and 2) and two new sesquiterpenoids, alternaterpenoids A and B (3 and 4), along with 18 known polyketides (5−22), were isolated from the marine-derived fungus Alternaria sp. 5102. Their structures were elucidated on the basis of extensive spectroscopic analyses (1D and 2D NMR, HR-ESIMS, and ECD) and X-ray crystallography, as well as the modified Mosher’s method. Compounds 2, 3, 5, 7, 9–18, and 20–22 exhibited potent anti-inflammatory activity by inhibiting the production of NO in RAW264.7 cells activated by lipopolysaccharide with IC50 values in the range from 1.3 to 41.1 μM. Structure-activity relationships of the secondary metabolites were discussed.

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