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Licorice, which is the underground part of Glycyrrhiza species, has been used widely in Asian and Western countries as a traditional medicine and as a food additive. Our continuous investigation on the constituents of roots and stolons of Glycyrrhiza uralensis led to the isolation of two new phenolics, in addition to 14 known compounds. Structural studies including spectroscopic and simple chemical derivatizations revealed that both of the new compounds had 2-aryl-3-methylbenzofuran structures. An examination of the effectiveness of licorice phenolics obtained in this study on vancomycin-resistant strains Enterococcus faecium FN-1 and Enterococcus faecalis NCTC12201 revealed that licoricidin showed the most potent antibacterial effects against both of E. faecalis and E. faecium with a minimum inhibitory concentration (MIC) of 1.9 × 10-5 M. 8-(γ,γ-Dimethylallyl)-wighteone, isoangustone A, 3'-(γ,γ-dimethylallyl)-kievitone, glyasperin C, and one of the new 3-methyl-2-phenylbenzofuran named neoglycybenzofuran also showed potent anti-vancomycin-resistant Enterococci effects (MIC 1.9 × 10-5-4.5 × 10-5 M for E. faecium and E. faecalis). The HPLC condition for simultaneous detection of the phenolics in the extract was investigated to assess the quality control of the natural antibacterial resource, and quantitative estimation of several major phenolics in the extract with the established HPLC condition was also performed. The results showed individual contents of 0.08%-0.57% w/w of EtOAc extract for the major phenolics in the materials examined.

This study aims to evaluate the anti-Leishmania major and the lung adenocarcinoma (A549) cytotoxicity of Withania somnifera root and fruit. The total extracts were obtained by homogenisation in aqueous MeOH, and the sub-extracts [n-hexane, ethyl acetate (EtOAc), n-butanol (n-BuOH), and methanol (MeOH)] were obtained by flash chromatography. The activity evaluation showed that n-BuOH sub-extracts from root and fruit exhibited noticeable antileishmanial promastigote properties. The n-hexane and EtOAc sub-extracts from both organs, and the MeOH sub-extract from the fruit exerted mild to moderate effects on the promastigotes. In-vitro growth-inhibitory test results on axenic amastigote and cytotoxicity testing on macrophages (RAW264.7), the parasite-host at the amastigote stage, revealed that the activity was mainly concentrated in the root EtOAc and n-BuOH sub-extracts and to a lesser extent the fruit MeOH and EtOAc, and the root n-hexane sub-extracts. Only the roots' EtOAc and n-BuOH sub-extracts demonstrated low cytotoxicity on the A549 cell line. [ABSTRACT FROM AUTHOR]

An ellagitannin monomer, lythracin M (1), and a dimer, lythracin D (2), along with eight known monomers (3 − 10) were isolated from Lawsonia inermis (Lythraceae) leaves. Lythracin M (1) is a C -glycosidic ellagitannin with a flavogallonyl dilactone moiety that participates in the creation of a γ-lactone ring with the anomeric carbon of the glucose core. Lythracin D (2) was determined as an atropisomer of the reported lythcarin D. These newly discovered structures (1 and 2) were determined by intensive spectroscopic experiments and by comparing DFT-calculated 1H 1H coupling, 1H NMR chemical shifts, and ECD data with experimental values. The anti-acetylcholinesterase assay of the compounds 1 – 10 revealed that the C-1 ellagitannin epimers [casuarinin (7 ; IC 50 = 34 ± 2 nM) and stachyurin (8 ; IC 50 = 56 ± 3 nM)], and the new dimer (2 ; IC 50 = 61 ± 4 nM) possess enzyme inhibitory effects comparable to the reference drug (donepezil, IC 50 = 44 ± 3 nM). Molecular docking of compounds 1 – 10 with AChE identified the free galloyl moiety as an important pharmacophore in the anticholinesterase activity of tannins. [Display omitted] • Two new (1 and 2) and eight known ellagitannins (3 – 10) were isolated from leaves of L. inermis. • The stereo-structure of 1 was established based on DFT calculations and intensive spectroscopic studies. • The anti-AChE activity of 1 – 10 was evaluated experimentally and by using molecular docking. • The ellagitannins 2 , 7 , and 8 are promising anti-AChE. [ABSTRACT FROM AUTHOR]

Chromatographic separation of an aqueous acetone extract of the galls from Tamarix aphylla using gels resulted in isolation of an ellagitannin, phyllagallin M1 ( 13 ), a gallo-ellagitannin, phyllagallin D1 ( 14 ), and four gallotannins, phyllagallin M2 ( 15 ) and phyllagallins D2–D4 ( 16 – 18 ), in addition to four known ellagitannins and three phenolics of lower molecular weight structurally related to hydrolyzable tannins. The structures of the six new tannins were elucidated based on spectroscopic and chemical data. Among the phenolics, flavogallonic acid dilactone ( 8 ), which is presumed to be biogenetically produced by C–C oxidative coupling of an ellagic acid unit with a galloyl residue, shows an exceptional oxidative pattern of gallic acid residues in plants of the family Tamaricaceae. Although the ellagitannin tamarixellagic acid ( 4 ) was reported to be a constituent of the galls of T. aphylla , such compounds with anomalous location of the DHDG moiety at O-3 on the glucopyranose core have not been observed among the tannins of tamaricaceous plants. [ABSTRACT FROM AUTHOR]

Abstract: Shoot cultures of Tamarix tetrandra on Linsmaier–Skoog (LS) agar medium with 30gl−1 sucrose, 2.13mgl−1 indoleacetic acid and 2.25mgl−1 benzyl adenine produced ellagitannins found in intact plants of the Tamaricaceae. This was demonstrated by the isolation of 14 monomeric–tetrameric ellagitannins from the aq. Me2CO extract of the cultured tissues. This is the first report on the production of ellagitannin tetramers by plant tissue culture. The effects of light and certain medium constituents on tissue growth and ellagitannin production were examined. The contents of representative tannins of different types [i.e., tellimagrandin II (monomer), hirtellin A (linear GOG-type dimer), hirtellin B (hellinoyl-type dimer), hirtellin C (macrocyclic-type dimer), and hirtellin T1 (linear GOG-type trimer)] in the resultant tissues in response to these factors were estimated by HPLC, and the optimal condition for production of these tannins were established. Shoots cultured on LS hormone-free medium promoted root development, and regenerated plants could adapt to ordinary soil and climate. Acclimatized and intact T. tetrandra plants that were collected in November and May, respectively, demonstrated seasonal differences in individual ellagitannin contents. HPLC comparison of individual ellagitannin contents in different plant materials (i.e., leaves, stems, and roots) of intact T. tetrandra plants is also reported. The results are discussed with respect to cellular deposition and biosynthetic relationship of tannins. [Copyright &y& Elsevier]

Investigation on tannins having antitumor properties led to the isolation of two new C -glycosidic ellagitannins (1 and 2) along with seven known ellagitannins (3 – 9) and a related polyphenolic constituent (10) from Lawsonia inermis leaves. Our intensive HRESIMS, 1D and 2D NMR, and ECD spectroscopic studies of new tannins have shown that one (1) has a monomer structure of C -glycosidic tannin, and the other (2) has a dimeric structure of 2,3- O -hexahydroxydiphenoyl glucopyranose and a C -glycosidic tannin. Among the known compounds, one (3) is a C -glycosidic tannin that was isolated first of all from nature, five were C -glycosidic tannins, vescalagin (4), 1- O -methylvescalagin (5), castalagin (6), stachyurin (7), and casuarinin (8), and one was an O- glycosidic ellagitannin, tellimagrandin II (9). The remaining phenolic constituent from the leaves was identified as valoneic acid dilactone (10). The ellagitannins 1 , and 3 – 9 demonstrated noticeable cytotoxicity on human oral squamous cell carcinoma cell lines (HSC-2, HSC-4, and Ca9–22), and lower effects on human oral normal cells (HGF, HPC, and HPLF). Tellimagrandin II (9) had the highest tumor-specific cytotoxicity, and also cleaved poly (ADP-ribose) polymerase 1 in HSC-2 cells. These findings showed that L. inermis ellagitannins may be a candidate for the production of anti-oral cancer materials. [Display omitted] • Two new (1 and 2), a first isolated from nature (3), and six knowns (4 – 9) ellagitannins, and a related phenolic (10) were isolated from leaves of L. inermis. • The ellagitannins (1 , 3 – 9) exhibited higher cytotoxicity against human oral cancer cell lines (HSC-2, HSC-4, and Ca9–22) than against human normal oral cells (HGF, HPC, and HPLF). • Tellimagrandin II (9) induced cleavage of PARP1 in HSC-2 cells. [ABSTRACT FROM AUTHOR]

Four flavanolignans, ceibapentains A (1) and B (2) and cinchonains Ia (3) and Ib (4), were isolated for the first time from an ethyl acetate extract of Ceiba pentandra (L) (Bombacaceae) aerial parts. The ceibapentains A (1) and B (2) are new compounds and their structures, including the absolute configurations, were determined by HRESIMS, 1D and 2D NMR, and electronic circular dichroism analyses, then compared with reported data. Compounds 1 – 4 were tested for their anti-Alzheimer's activity via an assessment of their inhibitory effect on amyloid β 42 aggregation using a thioflavin T assay. The results revealed that cinchonain Ia (3) showed a higher inhibitory effect (91%) than the standard curcumin (70%). Compounds 1 , 2 , and 4 exhibited moderate activity, with inhibition ratios of 43%, 47%, and 58%, respectively. A molecular docking study on the binding mode of 3 and curcumin with an amyloid β 1–40 peptide fibril structure indicated a high affinity of cinchonain 1a (3) towards amyloid β 1–40 peptide, in agreement with the experimental results. Unlabelled Image • Isolation of two new and two known flavanolignans from Ceiba pentandra • Investigation of the anti-Alzheimer's activities of the isolated compounds • Assessment of their inhibitory effect on amyloid β 42 aggregation • Molecular docking study on the binding mode of compounds with amyloid β 1–40 [ABSTRACT FROM AUTHOR]