Browsing by Author "Erdélyi, Máté"

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    N -Cinnamoyltetraketide Derivatives from the Leaves of Toussaintia orientalis
    (PubMed, 2015-07) Nyandoro, Stephen S.; Ndanu, Joseph; Munissi, Joan J. E.; Gruhonjic, Amra; Fitzpatrick, Paul A.; Landberg, Göran; Lu, Yu; Wang, Bin; Pan, Fangfang; Rissanen, Kari; Erdélyi, Máté
    Seven N-cinnamoyltetraketides (1-7), including the new Z-toussaintine E (2), toussaintine F (6), and toussaintine G (7), were isolated from the methanol extract of the leaves of Toussaintia orientalis using column chromatography and HPLC. The configurations of E-toussaintine E (1) and toussaintines A (3) and D (5) are revised based on single-crystal X-ray diffraction data from racemic crystals. Both the crude methanol extract and the isolated constituents exhibit antimycobacterial activities (MIC 83.3-107.7 μM) against the H37Rv strain of Mycobacterium tuberculosis. Compounds 1, 3, 4, and 5 are cytotoxic (ED50 15.3-105.7 μM) against the MDA-MB-231 triple negative aggressive breast cancer cell line.
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    Phytoconstituents with Radical Scavenging and Cytotoxic Activities from Diospyros shimbaensis
    (MDPI, 2016-01-15) Aronsson, Per; Munissi, Joan J. E.; Gruhonjic, Amra; Fitzpatrick, Paul A.; Landberg, Göran; Nyandoro, Stephen S.; Erdélyi, Máté
    As part of our search for natural products having antioxidant and anticancer properties, the phytochemical investigation of Diospyros shimbaensis (Ebenaceae), a plant belonging to a genus widely used in East African traditional medicine, was carried out. From its stem and root barks the new naphthoquinone 8,8′-oxo-biplumbagin (1) was isolated along with the known tetralones trans-isoshinanolone (2) and cis-isoshinanolone (3), and the naphthoquinones plumbagin (4) and 3,3′-biplumbagin (5). Compounds 2, 4, and 5 showed cytotoxicity (IC50 520–82.1 μM) against MDA-MB-231 breast cancer cells. Moderate to low cytotoxicity was observed for the hexane, dichloromethane, and methanol extracts of the root bark (IC50 16.1, 29.7 and > 100 μg/mL, respectively), and for the methanol extract of the stem bark (IC50 59.6 μg/mL). The radical scavenging activity of the isolated constituents (1–5) was evaluated on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The applicability of the crude extracts and of the isolated constituents for controlling degenerative diseases is discussed.
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    Selenium Accumulating Leafy Vegetables Are a Potential Source of Functional Foods
    (Hindawi Publishing Corporation, 2015-11-12) Mabeyo, Petro E.; Manoko, Mkabwa L. K.; Gruhonjic, Amra; Fitzpatrick, Paul A.; Landberg, Göran; Erdélyi, Máté; Nyandoro, Stephen S.
    Selenium deficiency in humans has been associated with various diseases, the risks of which can be reduced through dietary supplementation. Selenium accumulating plants may provide a beneficial nutrient for avoiding such illnesses. Thus, leafy vegetables such as Amaranthus hybridus, Amaranthus sp., Cucurbita maxima, Ipomoea batatas, Solanum villosum, Solanum scabrum, and Vigna unguiculata were explored for their capabilities to accumulate selenium when grown on selenium enriched soil and for use as a potential source of selenium enriched functional foods. Their selenium contents were determined by spectrophotometry using the complex of 3,3′-diaminobenzidine hydrochloride (DABH) as a chromogen. The mean concentrations in the leaves were found to range from to  μg/g dry weight (DW), with C. maxima accumulating the most selenium. In stems, the accumulated selenium content ranged from  μg/g in Amaranthus sp. to  μg/g DW in C. maxima and was hence significantly different (). The cancer cell line MDA-MB-231 was used in cytotoxicity assays to determine the anticancer potential of these extracts. With exception of S. scabrum and S. villosum, no cytotoxicity was detected for the selenium enriched vegetable extracts up to 100 μg/mL concentration. Hence, following careful evaluation the studied vegetables may be considered as selenium enriched functional foods.
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    Selenium Accumulating Leafy Vegetables Are a Potential Source of Functional Foods
    (Hindawi Publishing Cooperation, 2015) Mabeyo, Petro E.; Manoko, Mkabwa L.K.; Gruhonjic, Amra; Fitzpatrick, Paul A.; Landberg, Göran; Erdélyi, Máté; Nyandoro, Stephen S.
    Selenium deficiency in humans has been associated with various diseases, the risks of which can be reduced through dietary supplementation. Selenium accumulating plants may provide a beneficial nutrient for avoiding such illnesses. Thus, leafy vegetables such as Amaranthus hybridus, Amaranthus sp., Cucurbita maxima, Ipomoea batatas, Solanum villosum, Solanum scabrum, and Vigna unguiculata were explored for their capabilities to accumulate selenium when grown on selenium enriched soil and for use as a potential source of selenium enriched functional foods. Their selenium contents were determined by spectrophotometry using the complex of 3,3󸀠-diaminobenzidine hydrochloride (DABH) as a chromogen. The mean concentrations in the leaves were found to range from 7.90 ± 0.40 to 1.95 ± 0.12 𝜇g/g dry weight (DW), with C. maxima accumulating the most selenium. In stems, the accumulated selenium content ranged from 1.12 ± 0.10 𝜇g/g in Amaranthus sp. to 5.35 ± 0.78 𝜇g/g DW in C. maxima and was hence significantly different (𝑃 < 0.01). The cancer cell line MDA-MB-231 was used in cytotoxicity assays to determine the anticancer potential of these extracts. With exception of S. scabrum and S. villosum, no cytotoxicity was detected for the selenium enriched vegetable extracts up to 100 𝜇g/mL concentration. Hence, following careful evaluation the studied vegetables may be considered as selenium enriched functional foods.