Purification and characterization of two grandiuvarones from Desmos chinensis leaves and their antimicrobial activities.

A novel aromatic compound, grandiuvarone B (5-acetoxy-3-benzoyloxymethyl-5H-oxepin-4-one), along with a known compound grandiuvarone A (5-acetoxy-6-benzoyloxymethyl-5H-oxepin-4-one) were isolated from methanol extracts of Desmos chinensis leaves. Their structures were determined by various spectroscopic techniques including nuclear magnetic resonance (NMR), high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) and circular dichroism (CD). Grandiuvarone A and grandiuvarone B are isomers and the S configuration of grandiuvarone B was reported for the first time. We then determined their antifungal activity against Aspergillus flavus. Results revealed that grandiuvarone B exhibited better antifungal activity against A. flavus, with MIC values of 0.01 mg/mL compared to grandiuvarone A (MIC values of 0.02 mg/mL). In the presence of each active compound at 160 µg/g of aquafeed, A. flavus growth was completely inhibited. Grandiuvarone B also showed antibacterial activity against the plant pathogen Ralstonia solanacearum.

NMR reassignment of stictic acid isolated from a Sumatran lichen Stereocaulon montagneanum (Stereocaulaceae) with superoxide anion scavenging activities.

The phytochemical study of Stereocaulon montagneanum harvested in Sumatra (Indonesia) led to the isolation of 11 known compounds including two metabolites not previously described in the genus Stereocaulon, peristictic acid (8) and menegazziaic acid (10). The complete 1H and 13C NMR spectral assignments of stictic acid derivatives are reported with some revisions. Five depsidones belonging to the stictic acid chemosyndrome were superoxide anion scavengers as potent as ascorbic acid and with no toxicity on two human cell lines.

Two new phenolic compounds from the tuber of Sparganium stoloniferum.

Two new phenolic compounds, 2-(2-hydroxyphenyl)-4-methoxycarbonyl-5-hydroxybenzofuran (1) and 1-methoxycarbonyl-2, 3-dihydroxydibenzo[b, f]oxepine (2), were isolated from the tuber of Sparganium stoloniferum. The structures of both new compounds were determined on basis of spectroscopic means including HR-ESI-MS, 1D and 2D NMR experiments.

Dibenz[b,f]oxepin and Antimycobacterial Chalcone Constituents of Empetrum nigrum.

Two new dibenz[b,f]oxepins, empetroxepins A and B (1 and 2), and seven known compounds (3-9) were isolated from an extract of the Canadian medicinal plant Empetrum nigrum that significantly inhibited the growth of Mycobacterium tuberculosis H37Ra. The structures of 1 and 2 were established through analysis of NMR and MS data. The antimycobacterial activity of the plant extract was attributed primarily to the presence of two chalcone derivatives (6 and 7) that exhibited selective antimycobacterial activity (IC50 values of 23.8 and 32.8 µM, respectively) in comparison to mammalian (HEK 293) cells (IC50 values of 109 and 249 µM, respectively).

Lichen Secondary Metabolite, Physciosporin, Inhibits Lung Cancer Cell Motility.

Lichens produce various unique chemicals that can be used for pharmaceutical purposes. To screen for novel lichen secondary metabolites showing inhibitory activity against lung cancer cell motility, we tested acetone extracts of 13 lichen samples collected in Chile. Physciosporin, isolated from Pseudocyphellaria coriacea (Hook f. & Taylor) D.J. Galloway & P. James, was identified as an effective compound and showed significant inhibitory activity in migration and invasion assays against human lung cancer cells. Physciosporin treatment reduced both protein and mRNA levels of N-cadherin with concomitant decreases in the levels of epithelial-mesenchymal transition markers such as snail and twist. Physciosporin also suppressed KITENIN (KAI1 C-terminal interacting tetraspanin)-mediated AP-1 activity in both the absence and presence of epidermal growth factor stimulation. Quantitative real-time PCR analysis showed that the expression of the metastasis suppressor gene, KAI1, was increased while that of the metastasis enhancer gene, KITENIN, was dramatically decreased by physciosporin. Particularly, the activity of 3'-untranslated region of KITENIN was decreased by physciosporin. Moreover, Cdc42 and Rac1 activities were decreased by physciosporin. These results demonstrated that the lichen secondary metabolite, physciosporin, inhibits lung cancer cell motility through novel mechanisms of action.

Potent microbial and tyrosinase inhibitors from stem bark of Bauhinia rufescens (Fabaceae).

The stem bark extracts of Bauhinia rufescens Lam. (Fabaceae) yielded 6-methoxy-7-methyl-8-hydroxydibenz[b,f]oxepin, alpha-amyrin acetate, beta-sitosterol 3-O-beta-D-xylopyranoside, 4-(2'-Hydroxyphenethyl)-5-methoxy-2-methylphenol, menisdaurin and sequoyitol. Their structures were determined using spectroscopic methods and comparisons with the literature data. For the antimicrobial assay Gram-positive and Gram-negative bacterial and fungal strains were tested, while the tyrosinase inhibition assay utilized L-DOPA as a substrate for the tyrosinase enzyme. 6-Methoxy-7-methyl-8-hydroxydibenz[b,f]oxepin, a-amyrin acetate, beta-sitosterol 3-O-D-xylopyranoside, menisdaurin and sequoyitol showed weak to moderate activities with minimum inhibition concentration (MIC) values in the range of 112.5-900 microg/mL against all bacterial strains, while the MIC values for the fungal strains were in the range of 28.1-450 microg/mL. In the tyrosinase inhibition assay, a-amyrin acetate was found to be moderately active against tyrosinase with an inhibition of 62% at 0.1 mg/mL. This activity was lower than that of the positive control, kojic acid (85%).

Depsidones, aromatase inhibitors and radical scavenging agents from the marine-derived fungus Aspergillus unguis CRI282-03.

Three new depsidones ( 1, 3, and 4), a new diaryl ether ( 5), and a new natural pyrone ( 9) (synthetically known), together with three known depsidones, nidulin ( 6), nornidulin ( 7), and 2-chlorounguinol ( 8), were isolated from the marine-derived fungus ASPERGILLUS UNGUIS CRI282-03. Aspergillusidone C ( 4) showed the most potent aromatase inhibitory activity with the IC (50) value of 0.74 µM, while depsidones 1, 3, 6- 8 inhibited aromatase with IC (50) values of 1.2-11.2 µM. It was found that the structural feature of depsidones, not their corresponding diaryl ether derivatives (e.g. 5), was important for aromatase inhibitory activity. Aspergillusidones A ( 1) and B ( 3) showed radical scavenging activity in the XXO assay with IC (50) values of 16.0 and < 15.6 µM, respectively. Compounds 1 and 3- 7 were mostly inactive or showed only weak cytotoxic activity against HuCCA-1, HepG2, A549, and MOLT-3 cancer cell lines.

New stress metabolite from Bulbophyllum kwangtungense.

A new dibenz[b,f]oxepin (1) was found to be produced as a stress metabolite from the leaves and stems of Bulbophyllum kwangtungense Schlecht, in response to abiotic stress elicitation by CuCl2. The structure of 1 was established by spectroscopic and spectrometric means.

Phenolic compounds with cell protective activity from the fruits of Livistona chinensis.

Two new depsidones, livistones A (1) and B (2), and a new benzofurane, livistone C (3), together with the 11 known compounds including three stilbenes (4-6), four steroids, three flavan-3-ols, and an alkaloid were isolated from the fruits of Livistona chinensis. The structures of the new compounds were determined by spectroscopic methods. Compounds 1, 4-6 exhibited remarkable cell protective activities against H(2)O(2)-induced SH-SY5Y cell damage.

Stictic acid derivatives from the lichen Usnea articulata and their antioxidant activities.

Two new beta-orcinol depsidones, 1 and 2, together with 13 known compounds were isolated from the lichen Usnea articulata. The structures of 1 and 2 were elucidated by spectroscopic analyses and those of known compounds by comparison of their spectroscopic data with literature values or by direct comparison with authentic standards. Compounds 1, 2, and 5 exhibited moderate antiradical activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The depsidones 4 and 5 showed better superoxide anion scavenging activity (IC50 = 566 and 580 microM, respectively) than quercetin (IC50 = 754 microM).

Aromatic constituents of Uvaria grandiflora.

Grandiuvarone A (1) and grandiuvarins A-C (2-4) were isolated from the bark of Uvaria grandiflora. The structures of these new aromatic compounds were elucidated on the basis of spectroscopic analyses, especially 2D NMR techniques. Only compound 1 exhibited antileishmanial activity, with IC(50)/IC(90) values of 0.7/1.5 microg/mL. The positive controls pentamidine and amphotericin B had IC(50)/IC(90) values of 1.6/6.6 and 0.17/0.34 microg/mL, respectively.

Two new sesquiterpene lactones from Montanoa tomentosa ssp. microcephala.

Two new sesquiterpene lactones: 8alpha-(4'-acetoxymethacryloyloxy)-3alpha,9beta-dihydroxy-1(10)E,4Z,11(13)-germacratrien-12,6alpha-olide (1) and 8alpha-(2'E)-(2'-acetoxymethyl-2'-butenoyloxy)-3alpha,9beta-dihydroxy-1(10)E,4Z,11(13)-germacratrien-12,6alphaolide (2), together with the known zoapatanolide A were isolated from the aerial parts of Montanoa tomentosa Cerv. in La Llave et Lex ssp. microcephala (Sch. Bip. In K. Koch) V.A. Funk (Asteraceae). The structures of all compounds were established on the basis of 1D, 2D NMR, and EIMS analysis.

[Studies on chemical constituents from the root of Coriaria nepalensis wall (Coriaria sinica Maxim)].

The root of Coriaria nepalensis Wall (Coriaria sinica Maxim) is a Chinese herbal medicine and has been used to treat numbness, toothache due to wind and heat, phlegm-retention syndrome, traumatic injury and acute conjunctivitis. Nine compounds were isolated from the root of Coriaria nepalensis Wall and they were identified as braylin (I), norbraylin (II), dihydrocoriamyrtin (III), coriamyrtin (IV), tutin (V), coriatin (VI), apotutin (VII), hydroxycoriatin (VIII) and gallic acid (IX) on the basis of their physicochemical properties and IR, UV, MS, 1HNMR, 13CNMR data. I, II were isolated from the title plant for the first time; III was obtained from plant origin for the first time, and VII, VIII were new compounds.

The zoapatle. X. The in vitro effect of zoapatle aqueous crude extract (ZACE) and histamine upon rat and guinea pig uterine strips.

In vitro histamine response in rat and guinea pig uterine strips was similar to the one observed with zoapatle aqueous crude extract (ZACE). The relaxing effect elicited by ZACE/tomentosa on the in vitro rat uterine strips was not mediated by activation of H-2 histamine receptors; moreover, the increase on uterine contractility elicited by ZACE/tomentosa on the in vitro guinea pig uterine strip was not mediated through the activation of H-1 histamine receptors.

The zoapatle. XI. Effects elicited by Montanoa tomentosa and Montanoa frutescens on rat uterine strips.

Zoapatle aqueous crude extract (ZACE) obtained from Montanoa tomentosa (M.t.) inhibits the in vitro spontaneous contractility pattern of rat uterine tissue. The opposite effect was observed with ZACE from Montanoa frutescens (M.f.) in the same preparation. Both plant extracts, M.t. and M.f., increased the in vitro spontaneous contractility pattern in the uterine guinea pig assay. In depolarized uterine tissue, propranolol (beta-blocker) inhibited the relaxing effect induced by M.t.. Atropine (cholinergic antagonist) abolished the increase in uterus contractility produced by the presence of M.f.

The zoapatle. VII. Antiimplantation effect in the rat of zoapatle aqueous crude extract (ZACE) from Montanoa tomentosa and Montanoa frutescens.

Intrauterine administration of zoapatle aqueous crude extract (ZACE) from Montanoa frutescens on the fourth day of rat pregnancy, at concentrations equivalent to 50 mg and 5 mg of dry leaves, was associated with total inhibition of implantation sites. On the other hand, ZACE from Montanoa tomentosa equivalent to 50 and/or 100 mg of dry leaves, prepared and administered in the same fashion, did not inhibit the number of implants by day 11 of pregnancy. However, most implants were found abnormal, of blue color, poor orientation or spacing; these morphological changes could be considered as reabsorption sites.

The zoapatle. VIII. Ultrastructural changes in endometrium of rats.

Intrauterine administration of Zoapatle aqueous crude extract (ZACE) prepared from Montanoa tomentosa s.s.p. tomentosa, on day 4 of pregnancy, did not alter the normal uterine morphological changes by days 5 and 8 of pregnancy in the rat. On the other hand, ZACE made from Montanoa frutescens caused profound alterations on the uterine structures, such as: focal loss of epithelial lining, thickened blood vessels and alterations in stroma cells in rat endometrium. Morphological alterations correlate well with the antiimplantation effect associated with the intrauterine administration of these plant extracts. Scanning electron micrographs of leaves from Montanoa tomentosa and Montanoa frutescens revealed striking differences in glandular secretion and trichomes.

The zoapatle. IX. In vitro effect of Montanoa tomentosa and Montanoa frutescens upon human sperm and red cells.

The effect of zoapatle aqueous crude extract (ZACE) was further studied and partially characterized upon human and rabbit spermatozoa. ZACE prepared from Montanoa tomentosa s.s.p tomentosa did not influence sperm motility or viability in a wide range of ZACE concentrations tested; on the other hand, ZACE prepared from Montanoa frutescens had immediate and constant inhibitory effect upon motility and decreased cell viability. Red cell lysis was readily observed with ZACE-frutescens, but not with ZACE-tomentosa. The effect of time on ZACE-frutescens potency for inducing red cell lysis was observed.