Search

Marine-derived fungi can usually produce structurally novel and biologically potent metabolites. In this study, a new diketopiperazine alkaloid (1) and two new polyketides (10 and 11), along with 8 known diketopiperazine alkaloids (2-9) were isolated from marine-derived fungus Penicillium sp. TW58-16. Their structures were fully elucidated by analyzing UV, IR, HR-ESI-MS, 1D, and 2D NMR spectroscopic data. The absolute configurations of the new compounds 1, 10 and 11 were ascertained by X-ray diffraction (Cu Kα radiation) and comparing their CD data with those reported. In addition, the antibacterial activities of these compounds against Helicobacter pylori in vitro were assessed. Results showed that compounds 3, 6, 8 and 9 displayed moderate antibacterial activity against standard strains and drug-resistant clinical isolates of H. pylori in vitro. This result demonstrates that diketopiperazine alkaloids could be lead compounds to be explored for the treatment of H. pylori infection., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The hand-held mid-infrared diffuse reflectance infrared Fourier transform (MIR-DRIFT) spectrometer was used to assess the applicability of on-site and real time monitoring of total petroleum hydrocarbons (TPH) in contaminated soils during site characterization and remediation. Field measurement devices (MIR-DRIFT and turbidimetric screening test kits) were used to analyze reference soils with concentration ranging from 713 to 54790 mg/kg and compared with the results by a gas chromatography/mass spectrometry method (GC/MS). In situ field measurement of 147 petroleum-contaminated soil samples from 11 contaminated sites was correlated with laboratory-determined soil TPH levels by GC/MS. The concentrations of TPH by MIR-DRIFT were significantly correlated to the concentrations of TPH by GC/MS. Detection of TPH by the MIR spectrometer was not affected by the weathering effects of diesel-contaminated soils. Soils contaminated by mixed fuels with high content of gasoline constituents may cause the potential interference in MIR measurement. In field practice, interference may be attributed to soil moisture, soil organic matter, and soil texture. Soil moisture below 5% is required to reduce variation of infrared beam reflected from high level of surface liquid. When measuring the contaminated soil with a high organic matter content, the results may be overestimated due to the possible effects of surface reflection and interference. Clay and partial silty clay soils were not suitable for MIR spectrometer detection due to a potential shielding effect to reduce the infrared radiation absorbed by TPH. Future research is warranted to reduce the variation caused by soil texture and heterogeneity in TPH prediction., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Honey has been one previous natural food in human history. However, as the supply cannot satisfy the market demand, many incidents of adulterated and fraudulent honey have been reported. In Taiwan, some common adulterated honey and fraudulent honey incidents include (1) mixing honey with fructose, (2) importing cheap honey abroad but labeling them as domestic honey, and (3) labeling cheaper honey (for example, nectar and lychee honey) as high-price honey (for example, longan honey). It is very difficult for consumers to tell the genuineness of the labeling of honey. To protect consumers and honest honey producers, we aim at exploring and developing an efficient and convenient technology that can effectively classify honey. We analyze the infrared spectra of honey samples and apply machine learning technologies to classify honey. The experimental results confirm that this technology can effectively distinguish several main honey types in Taiwan. This technology has the advantages of non-destruction, immediacy, and low manpower. It can serve as an effective tool to fast screen honey products.

Characteristics transformation of humic acid extracted from natural water during the ozonation and biofiltration treatment processes was investigated based on the analyses of total organic carbon, UV absorbance, infrared spectroscopy, and gel permeation chromatography. With ozone doses of 1, 4, and 7 mg/L, high-molecular-weight humic acid was cleaved into low-molecular-weight particles and accumulated at group 6 (molecular weight < or = 4000 g/mole) on the Sephadex G-75 (Pharmacia Fine Chemicals, Uppsala, Sweden) fraction. Furthermore, the molecular-size distribution of organic compounds by Sephadex G-25 was shifted from groups 2 (molecular weight = 4000 to 400 g/mole) and 3 (molecular weight = 400 to 180 g/mole) to groups 2, 3, and 4 (molecular weight < or = 180 g/mole) under ozone doses of 1 and 4 mg/L. An increased ozone dose destroyed functional groups C=C and C-O of aromatic and phenolic compounds and increased UV-insensitive biodegradable organic carbon for subsequent biofiltration.

A novel skeletal norhumulene (1) and six xeniaphyllane-derived compounds, including norditerpenoids (2, 3) and diterpenoids (4-7), were isolated from the EtOAc extract of the Formosan soft coral Sinularia gibberosa. Their structures were elucidated by spectroscopic analysis. In vitro cytotoxic evaluation of the above metabolites revealed that 2 and 4 showed weak cytotoxicity toward a few cancer cell lines.

Chromatographic investigation of an extract of the octocoral Xenia umbellata afforded two new diterpenes, xenibelatols A (1) and B (2), in addition to three known xenicane diterpenes, 7,8-oxidoisoxeniolide (3), 9-hydroxyxeniolide F (4), and florlide C, and a cadinene sesquiterpene, xenitorin A (5). The structures were elucidated through spectroscopic analysis, especially 2D NMR.

Two new oleanane-type triterpenes, (23Z)-feruloylhederagenin (1) and (23E)-feruloylhederagenin (2), together with two known oleanane-type triterpenes, beta-amyrin acetate and beta-amyrin palmitate, have been isolated from the whole plant of Ludwigia octovalvis. The structures of 1 and 2 were characterised on the basis of spectral evidence.

A new quassinoid, ailantinol H, was isolated from the aerial parts of Ailanthus altissima. The structure was elucidated based on spectral evidence.

A new C19 gamma-lactone, cinnakotolactone (1), along with a known analogue, isolinderanolide B (2), were isolated from the n-hexane layer of the leaf extracts of Cinnamomum kotoense. Their structures were elucidated on the basis of spectroscopic analysis. The anti-proliferation activities of 1 and 2 were evaluated against human HT29 and MCF-7 cancer cell lines, and their IC50 values ranged from 3.3 +/- 0.3 to 25.8 +/- 5.3 microM.

A new quassinoid, ailantinol H, was isolated from a methanol extract of the aerial parts of Ailanthus altissima collected in Taiwan. Its structure was established on the basis of 1D and 2D NMR and HREIMS spectroscopic methods.

Three new dihydrophenanthrenes, 4-methoxy-9,10-dihydrophenanthrene-1,2,7-triol (1), 1-(4-hydroxybenzyl)-4,7-dimethoxy-9,10-dihydrophenanthrene-2-ol (2), and 1,3,6-tri(4-hydroxybenzyl)-4-methoxydihydrophenanthrene-2,7-diol (3) together with seven known phenanthrene derivatives, six known flavonoids, a bibenzyl and three phenolic compounds were isolated from the whole plant of Bletilla formosana. Their structures were elucidated by spectroscopic, mainly 2D NMR spectrometry and chemical methods.

Phytochemical investigation of the roots of Calophyllum blancoi growing in Taiwan resulted in the isolation of three new pyranoxanthones, blancoxanthone (1), acetyl blancoxanthone (2) and 3-hydroxyblancoxanthone (3), in addition to two known pyranoxanthones, pyranojacaeubin (4) and caloxanthone (5). Structural characterization of the isolated compounds was determined by spectral analyses especially 2-D NMR. Biological study of the isolated xanthones revealed that blancoxanthone (1) exhibited significant anti-coronavirus activity.

Phytochemical investigation of Ajuga taiwanensis resulted in the isolation of seven neoclerodane diterpenes, four of which ajugalide-A (1), -B (2), -C (3), and -D (4), are new and the remaining three are known diterpenes, ajugamacrin B (5), ajugapantin A (6), and ajugamarin C1 (7). Their structures were elucidated in spectral and chemical transformation studies.

Three new compounds, taraxacine-A (1), taraxacine-B (2) and taraxafolin (3) together with twenty-five known compounds, which include two beta-carboline alkaloids, two indole alkaloids, two chlorophylls, two flavonoids, one coumarin, two triterpenoids, one monoterpenoid, one ionone, four steroids and eight benzenoids, were isolated and characterized from the fresh aerial parts of Taraxacum formosanum. Structures of new compounds were determined by spectral analysis.

Six new cadinene sesquiterpenoids, xenitorins A-F (1-6), were isolated from the methylene chloride solubles of the Formosan soft coral Xenia puerto-galerae. The structures were elucidated by 1D and 2D NMR spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Four new lignans, 3',4'-O,O-demethylenehinokinin (1), chamalignolide (2), 8'beta-hydroxyhinokinin (3) and 7beta,8beta-epoxyzuonin A (4), as well as (-)-hinokinin (5), and (-)-zuonin A (6), were isolated from the heartwood of Chamaecyparis obtusa var. formosana. The structures of these lignans were unambiguously determined by spectroscopic methods. And the absolute configuration of 1 was elucidated with a circular dichroism (CD) spectrum.

Three new glycosides, pinocembrin 7-O-apiosyl(1-->5)apiosyl(1-->2)-beta-D-glucopyranoside (1), 2',3',4',3' '-tetramethoxy-1,3-diphenylpropane 5',4' '-di-O-beta-D-glucopyranoside (2), and rhamnocitrin 3-O-apiosyl(1-->5)apiosyl(1-->2)-[alpha-L-rhamnopyranosyl(1-->6)]-beta-D-glucopyranoside (3), were isolated from Viscum angulatumalong with viscumneoside V, naringenin, and homoeriodictyol. Their structures were established by spectral and chemical methods.

Two new A-type proanthocyanidins have been isolated from Ecdysanthera utilis and identified as epicatechin-(4beta-->8,2beta-->O-->7)-epicatechin-(4beta-->8)-epicatechin (5) and epicatechin-(4beta-->8)-epicatechin-(4beta-->8,2beta-->O-->7)-epicatechin-(4beta-->8)-epicatechin (6), respectively. The structure-related components epicatechin (1), procyanidin B2 (2), proanthocyanidin A1 (3), proanthocyanidin A2 (4), and aesculitannin C (7) were also isolated. All of these compounds were identified and evaluated for immunopharmacological activity. Human peripheral blood mononuclear cells (PBMC) were used as target cells, and cell proliferation was determined by (3)H-thymidine uptake. The results indicated that compound 3 suppressed PBMC proliferation activated with phytohemagglutinin (PHA). The inhibitory mechanisms may involve the blocking of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) production, since compound 3 attenuated IL-2 and IFN-gamma production of PBMC in a dose-dependent manner. Therefore, it is suggested that immunomodulatory agents are present in E. utilis.

Muurola-4,10(14)-dien-3-one (1), 10-O-acetyl-15-oxo-alpha-cadinol (2), 15-hydroxy-alpha-cadinol (3), 4alpha-hydroxy-5beta-ethoxy-epi-cubenol (4), and 4alpha-hydroxy-5beta-acetoxy-epi-cubenol (5), five new bicyclic sesquiterpenes, have been isolated from the heartwood of Chamaecyparis obtusa var. formosana along with the known compounds epi-cubenol, T-cadinol, T-muurolol, delta-cadinol, and alpha-cadinol. The structures of the new constituents were elucidated through chemical and spectral studies.

Three lanostanoids, 3beta-methoxycycloartan-24(24(1))-ene (1), 3beta,23beta-dimethoxycycloartan-24(24(1))-ene (2), and 3beta,23beta-dimethoxy-5alpha-lanosta-24(24(1))-ene (3), were isolated from the leaves of Amentotaxus formosana. The structures of new compounds 2 and 3 were determined by NMR and MS studies, and the structure of 3 was further confirmed by X-ray crystallographic analysis.

Fractionation of the acetone extract of Junceella juncea collected in Taiwan resulted in the isolation of a new briarane, designated juncenolide A (1). The structure of 1 was determined on the basis of 2D NMR techniques, including COSY, HSQC, HMBC, and NOESY experiments, and was also confirmed by X-ray crystallographic analysis.

Six new compounds, including one nor-neolignan, dehydroxymethylailanthoidol (1), and five butanolides, litseakolide D (2), litseakolide E (3), litseakolide F (4), litseakolide G (5), and isolincomolide D (6), were isolated from the leaves of Litsea acutivena. Their structures were elucidated from spectral analyses. The butanolides (2-6) showed significant cytotoxic activity against P-388, A549, and HT-29 cell lines in vitro.

Eight new sesquiterpenes, tubipolides A-G (1-7) and tubiporone (8) (novel carbon skeleton), and a known sesquiterpene, spirotubipolide, have been isolated from the Formosan stolonifer Tubipora musica. The structures of compounds 1-8 were determined by 1D and 2D NMR spectral analysis.

A novel type of alpha,beta-butenolide alkaloid, uncinine (1), two novel oxoaporphines, artabonatine C (2) and artabonatine D (3), a new oxazoloaporphine, artabonatine E (4), and a new 7,7'-bisdehydroaporphine, artabonatine F (5), along with 25 known alkaloids, were isolated from Artabotrys uncinatus. The structures of 1-5 were determined using NMR and mass spectral data. Atherospermidine and squamolone exhibited cytotoxicity against hepatocarcinoma cancer cell lines (Hep G(2) and 2,2,15), and the activity of some of the alkaloids in an antithrombin assay is also discussed.

Three new quinoline alkaloids, 2-acetylevolitrine (1), 2-acetylpteleine (2), and semecarpifoline (3), along with 26 known compounds were isolated from the root bark of Melicope semecarpifolia. The structures of 1-3 were elucidated by means of spectral analysis. In addition, (2S)-(--)-7,8-dimethoxyplatydesmine (4), cis-(+)-7,8-dimethoxymyrtopsine (5), and (3R)-(--)-8,9-dimethoxygeibalansine (6) were isolated as new natural products. Several of these isolates were determined as exhibiting significant antiplatelet aggregation activities in vitro.

Two phenanthraquinones were isolated from the stems of Dendrobium moniliforme. They were identified by interpretation of spectral data as 2,6-dimethoxy-1,4,5,8-phenanthradiquinone and 5-hydroxy-3,7-dimethoxy-1,4-phenanthraquinone, named moniliformin (1) and denbinobin (2), respectively. This is the first report of compound 1, which possesses a novel 1,4,5,8-diquinone moiety in the phenanthraquinone skeleton. Compound 2 showed potent antiinflammatory effects in vitro.

Six new cytotoxic dolabellane diterpenes, (1R,12R)-dolabella-4(16),7,10-triene-3,13-dione (1), (1R*,7R*,8S*,12R*)-dolabella-4(16),10-diene-7,8-epoxy- 3,13-dione (2), (1R*,10R*,11S*,12R*)-dolabella-4(16),7-diene-10,11-epoxy-3,13-dione (3), (1R)-dolabella-4(16),7,11(12)-triene-3,13-dione (4), (1R*,3R*)-3-hydroxydolabella-4(16),7,11(12)-triene-3,13-dione (5), and (1R*,7R*)-7-hydroperoxydolabella-4(16),8(17),11(12)-triene-3,13-dione (6), have been isolated from the Formosan soft coral Clavularia inflata. The structures of compounds 1-6 were determined by 1D and 2D spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Seven new annonaceous acetogenins, muricins A-G (1-7), as well as five known compounds, a mixture of muricatetrocin A (8) and muricatetrocin B (9), longifolicin (10), corossolin (11), and corossolone (12), were isolated from the seeds of Annona muricata. The structures of all isolates were elucidated and characterized by spectral and chemical methods. These acetogenins showed significantly selective in vitro cytotoxicities toward the human hepatoma cell lines Hep G(2) and 2,2,15.

Two new prenylflavanones, tanariflavanones A (1), and B (2), and one known compound, (-)-nymphaeol-C (3), were isolated from the fallen leaves of Macaranga tanarius. Compounds 1 and 2 showed inhibition of radical growth of lettuce seedlings at 200 ppm. Their structures were elucidated primarily by NMR, circular dichroism, and mass spectroscopic methods.

In addition to metachromins A (1), B (2), and E (9), two new sesquiterpene hydroquinones, hippochromins A and B (3, 4), were isolated from the Taiwanese marine sponge Hippospongia metachromia. The structures of 4--6 were established by extensive 2D NMR analysis. Metachromins A (1) and B (2), hippochromin A diacetate (5), and metachromin B monoacetate (8) exhibited potent cytotoxicities against human colon (COLO-205) and nasopharyngeal (KB) tumor cells, while compounds 6, 7, and 9 were inactive.

Chemical investigation of Drypetes littoralis yielded three new tricyclic diterpenes, drypetenones A, B, and C (1--3), and one new xanthone (4). Spectral analyses and chemical correlations established the structures as 10S-12-hydroxy-11-methoxy-13-methylpodocarpa-1,5,8,11,13-pentaene-3,7-dione, (1), 10S-12-hydroxy-11-methoxy-13-methylpodocarpa-5,8,11,13-tetraene-3,7-dione (2), 10S-12-hydroxy-6,11-dimethoxy-13-methylpodocarpa-1,5,8,11,13-pentaene-3,7-dione (3), and 1-hydroxy-7-hydroxymethyl-6-methoxyxanthone (4). Complete (13)C NMR assignment of boehmenan D (5) is also made.

Two minor diterpenoids, 15(16)-peroxy-3, 13-clerodadien-18-oic acid (4) and totarol (7), were isolated from the liverwort Schistochila acuminata. The former is a further oxidized cyclic peroxide from the major component. The latter is a rearranged abietane alcohol which skeleton was found in liverworts for the first time.

Three new phenanthrene derivatives, aristoliukine-C, aristofolin-E and aristolochic acid-Ia methyl ester, and one new sesquiterpene, madolin-P, together with 58 known compounds were isolated from the stem and root of Aristolochia kaempferi. The structures of these compounds were determined by spectral analysis. The cytotoxicity and antiplatelet activity of the isolated compounds are also discussed.

Investigation of extracts of Fissistigma balansae and Fissistigma oldhamii resulted in the isolation of 11 aristolactams-stigmalactam (1), piperolactam A (2), piperolactam C (3), aristolactam AII (4), aristolactam AIIIa (5), aristolactam BII (6), aristolactam BIII (7), aristolactam FII (8), goniothalactam (9), enterocarpam I (10), and velutinam (11)-as well as two dioxoaporphines, noraristolodione (12) and norcepharadione B (13). The new compound 1 was identified by spectral data interpretation. Compounds 1-13 were subjected to antiplatelet aggregation testing.

Five new podocarpane-type trinorditerpenes were isolated from the bark of Taiwania cryptomerioides. Structures of 1beta, 14-dihydroxy-13-methoxy-6,8,11,13-podocarpatetraene (1), 1beta, 14-dihydroxy-13-methoxy-8,11,13-podocarpatriene (2), 13-hydroxy-12-methoxy-8,11,13-podocarpatrien-3-one (3), 14-hydroxy-13-methoxy-1,8,11,13-podocarpatetraen-3-one (4), and 13-methoxy-8,12-podocarpatriene-11,14-dione (5) were determined by NMR, MS, and other spectral and chemical evidence.

A p-hydroxyacetophenone-like derivative, (+)-gynunone, and a chromane, together with six known compounds were isolated from the CHCl3 fraction of the roots of Gynura elliptica. Their structures were determined by means of spectral analyses. Among the isolates, 6-acetyl-2,2-dimethylchroman-4-one and vanillin showed anti-platelet aggregation activity induced by arachidonic acid in vitro.

Bioassay-directed fractionation of an ethanolic extract of Cephalotaxus wilsoniana has resulted in the isolation of a novel C-methylated biflavone, taiwanhomoflavone-A (1). Its structure was elucidated on the basis of spectroscopic analysis. Taiwanhomoflavone-A is cytotoxic with ED50 values of 3.4, 1.0, 2.0 and 2.5 microg/ml, respectively, against KB epidermoid carcinoma of nasopharynx, COLO-205 colon carcinoma, Hepa-3B hepatoma, and Hela cervix tumor cells.

Two new cytotoxic cembranoid diterpenes, brassicolide (1) and brassicolide acetate (2); a new cytotoxic sesquiterpene, (-)-4alpha-O-acetyl-selin-11-en (3); and six cytotoxic terpenoids, (-)-selin-11-en-4alpha-ol (4), 2-hydroxynephthenol (5), nephthenol (6), cembrene A (7), epoxycembrene A (8), and (-)-beta-elemene (9), have been isolated from the Formosan soft coral Nephthea brassica. The structures of compounds 1-9 were determined by spectral, chemical, and X-ray crystallographic analysis.

A new C18 dibenzocyclooctadiene lignan, kadsumarin A (1) was isolated from Kadsura matsudai Hayata and Schizandra arisanensis Hayata. The anti-HBeAg test revealed that kadsumarin A had activity at a concentration of 40 micrograms/ml (= 90.1 microM). Its structural elucidation by spectral analysis was discussed in this note.

Through continuing studies on the chemical constituents and antiplatelet aggregation principles of the fruit of the Formosan Zanthoxylum integrifoliolum, four new compounds-including two new lignans, (+)-pinoresinol-di-3,3-dimethylallyl ether (1), and (+)-pinoresinol-3,3-dimethylallyl ether (2); zanthonitrile (3), and one new flavonoid, 3,5-diacetyltambulin (4)-and 18 known compounds were isolated from the CHCl3-soluble fraction. Their structures were elucidated on the basis of spectral data and chemical evidence. Among the isolates, including the previously reported isobutylamides, 13 compounds showed strong in vitro antiplatelet aggregation activity, with only (-)-tetrahydroberberine showing weak vasorelaxing effect in high potassium- or norepinephrine-induced contraction of rat aorta.

Five new diterpenes, 3beta-acetoxyabieta-8,11,13-trien-12-ol (1), 8alpha-hydroxy-13(16),14-labdadien-19-al (2), 16-hydroxy-19-oxomanoyl oxide (3), 15-nor-14-oxo-8(17), 12-labdadiene-18-ol (4), and 15,16-bisnor-13-oxo-8(17), 11-labdadien-18-ol (5), were isolated from the wood of Cunninghamia konishii. Their structures were elucidated by 2D NMR spectroscopy and by chemical methods.

Four new eremophilane-type sesquiterpenes, petasones A (1) and B (2), S-petasitin (3), and petasinol (4), were isolated from the aerial parts of Petasites formosanus. Their structures were elucidated by spectroscopic and chemical methods as 3alpha-[(Z)-3-methylsulfinylacryloxy]eremophila-7(11), 9-dien-8-one; 3alpha-[(E)-3-methylsulfinylacryloxy]eremophila-7(11), 9-dien-8-one; 3alpha-[(Z)-3-methylthioacryloxy]-11-hydroxyeremophila -6, 9-dien-8-one; and 3alpha-[(E)-3-methylsulfinylacryloxy]-8beta-hydroxy eremophila-9, 11-diene, respectively.

Using a bioassay-directed fractionation method, three new compounds, including an aporphine alkaloid, cassyformine (4); an oxoaporphine alkaloid, filiformine (8), and a lignan, (+)-diasyringaresinol (10), along with 14 known compounds, were further isolated and characterized from the MeOH extract of the fresh herbs of Cassytha filiformis. Among the isolates of this plant, cathafiline (1), cathaformine (2), actinodaphnine (3), N-methylactinodaphnine (5), predicentrine (6), and ocoteine (7) exhibited significant antiplatelet aggregation activity.

The MeOH extract of the seeds of Psoralea corylifolia L. was found to inhibit the aggregation of rabbit platelets induced by arachidonic acid, collagen, and platelet activating factor. Bioassay-directed fractionation led to the isolation of three flavonoids, isobavachalcone (1), neobavaiso-flavone (2), and bavachin (3). Compounds 1 and 2 inhibited platelet aggregation.

A known steroid, in addition to triterpenoids, anthraquinones, naphthalenes and a new anthraquinone glycoside, xanthopurpurin 3-O-beta-D-glucoside, were isolated from the roots of Rubia akane grown in Taiwan. Mollugin, a naphthohydroquinone, showed strong inhibition of arachidonic acid (AA)-induced and collagen-induced platelet aggregation. In contrast, 2-methyl-1,3,6-trihydroxyl-9,10-anthraquinone, xanthopurpurin 3-O-beta-D-glucoside, and xanthopurpurin showed mainly strong inhibition of collagen-induced platelet aggregation.