zur Suche springenzur Navigation springenzum Inhalt springen

Sortieren nach: Erscheinungsjahr Typ der Publikation

Zeige Ergebnisse 1 bis 9 von 9.

Publikation

Alresly, Z.; Lindequist, U.; Lalk, M.; Porzel, A.; Arnold, N.; Wessjohann, L. A.; Bioactive Triterpenes from the Fungus Piptoporus betulinus Rec. Nat. Prod. 10, 103-108, (2016)

Phytochemical investigation of the ethyl acetate extract of the fruiting bodies from the basidiomycete Piptoporus betulinus led to the isolation of a new bioactive lanostane triterpene identified as 3 b -acetoxy-16-hydroxy-24-oxo-5α-lanosta-8- ene-21-oic acid (1). In addition, ten known triterpenes, polyporenic acid A (5), polyporenic acid C (4), three derivatives of polyporenic acid A (8, 10, 11), betulinic acid (3), betulin (2), ergosterol peroxide (6), 9,11-dehydroergosterol peroxide (7), and fomefficinic acid (9), were also isolated from the fungus. All isolated compounds were tested for antimicrobial activity against some Gram-positive and Gram-negative bacteria as well as against a fungal strain. The new triterpene and some of the other compounds showed antimicrobial activity against Gram-positive bacteria.
Publikation

Al-Fatimi, M.; Ali, N. A. A.; Kilian, N.; Franke, K.; Arnold, N.; Kuhnt, C.; Schmidt, J.; Lindequist, U.; Ethnobotany, chemical constituents and biological activities of the flowers of Hydnora abyssinica A.Br. (Hydnoraceae) Pharmazie 71, 222-226, (2016) DOI: 10.1691/ph.2016.5808

Hydnora abyssinica A.Br. (Hydnoraceae), a holoparasitic herb, is for the first time recorded for Abyan governorate of South Yemen. Flowers of this species were studied for their ethnobotanical, biological and chemical properties for the first time. In South Yemen, they are traditionally used as wild food and to cure stomach diseases, gastric ulcer and cancer. Phytochemical analysis of the extracts showed the presence of terpenes, tannins, phenols, and flavonoids. The volatile components of the air-dried powdered flowers were identified using a static headspace GC/MS analysis as acetic acid, ethyl acetate, sabinene, α-terpinene, (+)-D-limonene and γ-terpinene. These volatile compounds that characterize the odor and taste of the flowers were detected for the first time in a species of the family Hydnoraceae. The flowers were extracted by n-hexane, dichlormethane, ethyl acetate, ethanol, methanol and water. With exception of the water extract all extracts demonstrated activities against Gram-positive bacteria as well as remarkable radical scavenging activities in DPPH assay. Ethyl acetate, methanol and water extracts exhibited good antifungal activities. The cytotoxic activity of the extracts against FL cells, measured in neutral red assay, was only weak (IC50 > 500 μg /mL). The results justify the traditional use of the flowers of Hydnora abyssinica in South Yemen.
Publikation

Ali, N. A. A.; Wurster, M.; Denkert, A.; Al-Sokari, S. S.; Lindequist, U.; Wessjohann, L.; Cytotoxic and antiphytofungal activity of the essential oils from two artemisia species World J. Pharm. Res. 3, 1350-1354, (2014)

Hydrodistilled essential oils from aerial parts of Artemisia abyssinica Sch.Bip. ex A. Rich, and Artemisia arborescens L. growing in Yemen were screened for their cytotoxic and antiphytofungal properties as well as their chemical compositions. Twenty-seven components were identified in the essential oils and the main components of these species were found to be davanone (42.34%), camphor (22.88%), nerolidol (8.96%), and chamazulene (4.46%), from A. abyssinica oil and artemisia ketone (51.05%), camphor (14.09%), α-bisabolol (12.56%) and α-phellandrene (8.69%) from A. arborescens. At concentration of 50 and 25 μg/mL, A. arborescens oil showed a strong cytotoxic activity with growth inhibition of 95%(±1.6) and 74%(±3.8) (IC50 of 16.91 μg/mL) against HT29 tumor cells (Human colonic adenocarcinoma cells), while A. abyssinica oil exhibited at concentration of 100 and 50 μg/mL growth inhibition of 71.0% (±12.5) and 27.3%(±14.4) (IC50 of 75.42 μg/mL) respectively. Bioautographic assay was used to evaluate the antiphytofungal activity of the oils against Cladosporium cucumerinum.
Publikation

Tarman, K.; Palm, G. J.; Porzel, A.; Merzweiler, K.; Arnold, N.; Wessjohann, L. A.; Unterseher, M.; Lindequist, U.; Helicascolide C, a new lactone from an Indonesian marine algicolous strain of Daldinia eschscholzii (Xylariaceae, Ascomycota) Phytochem. Lett. 5, 83-86, (2012) DOI: 10.1016/j.phytol.2011.10.006

From an endophytic Daldinia eschscholzii strain isolated from the agar-producing red alga Gracilaria sp. SGR-1, collected from the coast of South Sulawesi, Indonesia, a new lactone helicascolide C (1) was obtained as colourless crystals from the ethyl acetate extract together with the related structurally known compound helicascolide A (2). The structure of the new compound 1 reveals a carbonyl group replacing an alcohol group of compound 2. The structure of 1 was elucidated by X-ray diffraction and spectral analyses. Compound 1 showed fungistatic activity against the phytopathogenic fungus Cladosporium cucumerinum.
Publikation

Ali, N. A. A.; Wurster, M.; Denkert, A.; Arnold, N.; Fadail, I.; Al-Didamony, G.; Lindequist, U.; Wessjohann, L.; Setzer, W. N.; Chemical Composition, Antimicrobial, Antioxidant and Cytotoxic Activity of Essential Oils of Plectranthus cylindraceus and Meriandra benghalensis from Yemen Nat. Prod. Commun. 7, 1099-1102, (2012) DOI: 10.1177/1934578X1200700834

The chemical composition, antimicrobial, antioxidant and cytotoxic activities of the essential oils isolated from the leaves of Plectranthus cylindraceus Hoechst. ex. Benth. (EOPC) and Meriandra benghalensis (Roxb.) Benth. (EOMB) were investigated. Sixteen compounds were identified in P. cylindraceus oil representing 94.5% of the oil content with thymol (68.5%), terpinolene (5.3%), β-selinene (4.7%), β-caryophyllene (4.0%), δ-cadinol (2.1%), and ar-curcumene (1.7%) as the major compounds. In M. benghalensis oil, 12 compounds were identified, which made up 82.0% of the total oil. The most abundant constituents were camphor (43.6%), 1,8-cineole (10.7%), α-eudesmol (5.8%), caryophyllene oxide (5.8%), camphene (5.3%) and borneol (3.4%). The antimicrobial activities of both oils were evaluated against five microorganisms with the disc diffusion test, the broth micro-dilution method and a semiquantitative bioautographic test. The most sensitive microorganisms for P. cylindraceus oil were S. aureus, B. subtilis, and C. albicans with inhibition zones of 38, 42, and 43 mm and MIC values of 0.39, 0.18, and, 0.18 μL/mL, respectively. M. benghalensis oil showed weak to moderate activity against the tested microorganisms. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay was employed to study the potential antioxidant activities of both oils. The antioxidant activity of P. cylindraceus oil (IC50 34.5 μg/mL) appeared to be higher than that of M. benghalensis oil (IC50 935 μg/mL). At a concentration of 100 μg/mL, EOMB showed a stronger cytotoxic activity, with growth inhibition of 71% against HT29 tumor cells, than EOPC (18%).
Publikation

Tarman, K.; Lindequist, U.; Wende, K.; Porzel, A.; Arnold, N.; Wessjohann, L. A.; Isolation of a New Natural Product and Cytotoxic and Antimicrobial Activities of Extracts from Fungi of Indonesian Marine Habitats Mar. Drugs 9, 294-306, (2011) DOI: 10.3390/md9030294

In the search for bioactive compounds, 11 fungal strains were isolated from Indonesian marine habitats. Ethyl acetate extracts of their culture broth were tested for cytotoxic activity against a urinary bladder carcinoma cell line and for antifungal and antibacterial activities against fish and human pathogenic bacteria as well as against plant and human pathogenic fungi. The crude extract of a sterile algicolous fungus (KT31), isolated from the red seaweed Kappaphycus alvarezii (Doty) Doty ex P.C. Silva exhibited potent cytotoxic activity with an IC50 value of 1.5 µg/mL. Another fungal strain (KT29) displayed fungicidal properties against the plant pathogenic fungus Cladosporium cucumerinum Ell. et Arth. at 50 µg/spot. 2-Carboxy-8-methoxy-naphthalene-1-ol (1) could be isolated as a new natural product.
Publikation

Ali, N. A. A.; Wurster, M.; Arnold, N.; Lindequist, U.; Wessjohann, L.; Essential Oil Composition from Oleogum Resin of Soqotraen Commiphora kua Rec. Nat. Prod. 2, 70-75, (2008)

The major constituents of the essential oil obtained by hydrodistillation from the oleogum resin of Commiphora kua Vollesen were identified by GC-MS. Sixteen constituents were detected from the essential oil, which constituted about (90.5%) of the total amount. Major constituents of the oil were α- cadinol (33.0%), g -cadinene (22.5%), d -cadinene (17.0%), isocaryophyllene (3.7%), allo-aromadendrene (2.8%), α-muurolene (2.7%), and α-humulene (2.4%). The Oil of Commiphora kua showed moderate antifungal activity against Cladosporium cucumerinum.
Publikation

Ali, N. A. A.; Wurster, M.; Arnold, N.; Lindequist, U.; Wessjohann, L.; Chemical Composition of the Essential Oil of Teucrium yemense Deflers Rec. Nat. Prod. 2, 25-32, (2008)

The chemical composition of the essential oil (EO) obtained by hydrodistillation from the leaves of Teucrium yemense Deflers was determined by GC-MS. Twelve compounds accounting to 77.7% of the total oil were identified. Sesquiterpene hydrocarbons (73.9%) were the predominant portion of the oil with δ-cadinene (34.9%), β-caryophyllene (22.7%), a -humulene (6.1%), and a -selinene (5.4%) as the main constituents.
Publikation

Ali, N. A. A.; Wurster, M.; Arnold, N.; Teichert, A.; Schmidt, J.; Lindequist, U.; Wessjohann, L.; Chemical Composition and Biological Activities of Essential Oils from the Oleogum Resins of Three Endemic Soqotraen Boswellia Species Rec. Nat. Prod. 2, 6-12, (2008)

The chemical composition, antioxidant and anticholinesterase activity of three essential oils (EOs) obtained from the oleogum resin of three endemic Sqotraen Boswellia species, Boswellia socotrana Balf. f, Boswellia ameero Balf. f, andBoswellia elongata Balf. f were determined. GC-MS technique was used for the analysis of the oils. Oils of B. socotrana and B. ameero were characterized by a high content of monoterpenes. The main constituens of B. socotrana and B. ameero were (E)-2,3-epoxycarene (51.8%), 1,5-isopropyl-2-methylbicyclo[3.1.0]hex-3-en-2-ol (31.3%), and a -cymene (7.1%); (3E,5E)-2,6-dimethyl-1,3,5,7-octatetraene (34.9%), 1-(2,4-Dimethylphenyl)ethanol (20.3%), 3,4-dimethylstyrene (17.3%), a -campholenal (13.4%) and a -terpineol (12.4%) respectively. The composition of B. elongata oil was dominated by the diterpene verticiol (52.4%), the sesquiterpene caryophellene (39.1%) and methylcycloundecanecarboxylate (7.8%). The oils were screened for their antioxidant activity by using the DPPH free radical scavenger assay and their anticholinesterase activity on acetylcholinesterase enzyme by using in vitro Ellman method. The antioxidant activity of EOs from B. socotrana (IC 50 =121.4 µg/mL) appeared to be more potent than that of B. elongata (IC 50 =211.2 µg/mL) and B. ameero (IC 50 =175.2 µg/mL). EO of B. socotrana showed the higher AChE inhibitory activity with 59.3% at concentration of 200 μ g/mL in comparison to EOs of B. elongata and B. ameero (29.6, 41.6 enzyme inhibition) respectively.
IPB Mainnav Search