9 research outputs found
Isolation and antimicrobial activity of rutin and its derivatives from Ruta chalepensis (Rutaceae) growing in Iraq
Rutin (1), rutin 3'-methyl ether (2), and a new flavonol glycoside, 6-hydroxy-rutin 3',7-dimethyl ether (3), were isolated from the methanol extract of the fruits of Ruta chalepensis, collected from Diyala, Iraq. Their structures were elucidated by spectroscopic analyses, including 1D-, 2D-NMR and HRESIMS. Antimicrobial activity of compounds 1-3 was tested against four Gram +ve and Gram –ve bacterial strains, and the only fungal strain, Candida albicans, using the 96-well based resazurin microtitre assay
Chalepin and Chalepensin: Occurrence, Biosynthesis and Therapeutic Potential
Dihydrofuranocoumarin, chalepin (1) and furanocoumarin, chalepensin (2) are 3-prenylated bioactive coumarins, first isolated from the well-known medicinal plant Ruta chalepensis L. (Fam: Rutaceae) but also distributed in various species of the genera Boenminghausenia, Clausena and Ruta. The distribution of these compounds appears to be restricted to the plants of the family Rutaceae. To date, there have been a considerable number of bioactivity studies performed on coumarins 1 and 2, which include their anticancer, antidiabetic, antifertility, antimicrobial, antiplatelet aggregation, antiprotozoal, antiviral and calcium antagonistic properties. This review article presents a critical appraisal of publications on bioactivity of these 3-prenylated coumarins in the light of their feasibility as novel therapeutic agents and investigate their natural distribution in the plant kingdom, as well as a plausible biosynthetic route
Anti-MRSA Constituents from Ruta chalepensis (Rutaceae) Grown in Iraq, and In Silico Studies on Two of Most Active Compounds, Chalepensin and 6-Hydroxy-rutin 3’,7-Dimethyl ether
Ruta chalepensis L. (Rutaceae), a perennial herb with wild and cultivated habitats, is well known for its traditional uses as an anti-inflammatory, analgesic, antipyretic agent, and in the treatment of rheumatism, nerve diseases, neuralgia, dropsy, convulsions and mental disorders. The antimicrobial activities of the crude extracts from the fruits, leaves, stem and roots of R. chalepensis were initially evaluated against two Gram-positive and two Gram-negative bacterial strains and a strain of the fungus Candida albicans. Phytochemical investigation afforded 19 compounds, including alkaloids, coumarins, flavonoid glycosides, a cinnamic acid derivative and a long-chain alkane. These compounds were tested against a panel of methicillin-resistant Staphylococcus aureus (MRSA) strains, i.e., ATCC 25923, SA-1199B, XU212, MRSA-274819 and EMRSA-15. The MIC values of the active compounds, chalepin (9), chalepensin (10), rutamarin (11), rutin 3′-methyl ether (14), rutin 7,4′-dimethyl ether (15), 6-hydroxy-rutin 3′,7-dimethyl ether (16) and arborinine (18) were in the range of 32–128 µg/mL against the tested MRSA strains. Compounds 10 and 16 were the most active compounds from R. chalepensis, and were active against four out of six tested MRSA strains, and in silico studies were performed on these compounds. The anti-MRSA activity of compound 16 was comparable to that of the positive control norfloxacin (MICs 32 vs 16 mg/mL, respectively) against the MRSA strain XU212, which is a Kuwaiti hospital isolate that possesses the TetK tetracycline efflux pump. This is the first report on the anti-MRSA property of compounds isolated from R. chalepensis and relevant in silico studies on the most active compounds
Sonneratinone: A New Antimicrobial Benzofuranone Derivative from the Endophytic Fungus Aspergillus niger Isolated from the Mangrove Plant Sonneratia apetala Buch.-Ham
A new antimicrobial benzofuranone derivative, named, sonneratinone (1), was isolated from the endophytic fungus Aspergillus niger, obtained from the leaves of Sonneratia apetala, a mangrove plant from the Sundarbans. Whilst the fungal strain was identified by macroscopic, microscopic and molecular techniques, the structure of the new compound was elucidated by spectroscopic means, e.g., 1D and 2D NMR, and HRESIMS. Sonneratinone (1) showed considerable antimicrobial activity against Micrococcus luteus, Staphylococcus aureus and Candida albicans in the resazurin 96-well microtitre plate antimicrobial assay
Anti-MRSA Activity of Oxysporone and Xylitol from the Endophytic Fungus Pestalotia sp. Growing on the Sundarbans Mangrove Plant Heritiera fomes
Heritiera fomes Buch.-Ham., a mangrove plant from the Sundarbans, has adapted to a unique habitat, muddy saline water, anaerobic soil, brackish tidal activities and high microbial competition. Endophytic fungal association protects this plant from adverse environmental conditions. This plant is used in Bangladeshi folk medicine, but it has not been extensively studied phytochemically, and there is hardly any report on investigation on endophytic fungi growing on this plant. In this study, endophytic fungi were isolated from the surface sterilized cladodes and leaves of H. fomes. The antimicrobial activities were evaluated against two Gram-positive and two Gram-negative bacteria and the fungal strain, Candida albicans. Extracts of Pestalotia sp. showed activities against all test bacterial strains, except that the EtOAc extract was inactive against E. coli. The structures of the purified compounds, oxysporone and xylitol, were elucidated by spectroscopic means. The anti-MRSA potential of the isolated compounds were determined against various MRSA strains, i.e., ATCC 25923, SA-1199B, RN4220, XU212, EMRSA-15 and EMRSA-16, with MIC values ranging from 32-128 g/mL. This paper, for the first time, reports on the anti-MRSA property of oxysporone and xylitol, isolation of the endophyte Pestalotia sp. from H. fomes, and isolation of xylitol from a Pestalotia sp
Flavonoids from two Turkish Centaurea species and their chemotaxonomic implications
Centaurea asutro-anatolica Hub.-Mor. and C. kizildaghensis Uzunh., E. Doğan & H. Duman, two indigenous perennial herbs from the Turkish flora, belong to the medicinally important genus Centaurea L. (fam: Asteraceae), which comprises ca. 600 species worldwide. While various Centaurea species are well-known for producing alkaloids, flavonoids, lignans and terpenoids, there is no report on any thorough phytochemical work on any of these two species available to date. In continuation of our phytochemical and bioactivity studies on the Turkish Centaurea species, four flavonoids apigenin (1), apigenin 7,4’-dimethyl ether (2), genkwanin (3) and quercetin (4) were isolated from the methanol extracts of the aerial
parts of C. austro-anatolica and C. kizildaghensis, for the very first time. The structures of the flavonoids were elucidated conclusively by spectroscopic means, i.e., UV, MS and 1D and 2D NMR data analyses. The distribution of these flavonoids (1-4) within the genus Centaurea and their possible chemotaxonomic implications within the genus Centaurea or the family Asteraceae have been discussed
Antimicrobial activity of kojic acid from endophytic fungus Colletotrichum gloeosporioides isolated from Sonneratia apetala, a mangrove plant of the Sundarbans
Objective: To isolate and evaluate the antimicrobial activity of the active principle(s) from the ethyl acetate (EtOAc) extract of endophytic fungus Colletotrichum gloeosporioides (C. gloeosporioides) isolated from Sonneratia apetala. Methods: Water agar technique was used to isolate the fungus, and both microscopic and molecular techniques were used for identification of the strain. Potato dextrose broth was used to grow the fungus in large-scale. Reversed-phase preparative HPLC analysis was performed to isolate the major active compound, kojic acid. The EtOAc extract and kojic acid were screened for their antimicrobial activity against two Gram-positive and two Gram-negative bacteria as well as a fungal strain using the resazurin 96-well microtitre plate antimicrobial assay. Results: The fungus C. gloeosporioides was isolated from the leaves of Sonneratia apetala. Initial identification of the fugal isolate was carried out using spore characteristics observed under the microscope. Subsequently, the ITS1-5.8S-ITS2 sequencing was employed for species-level identification of the fungus C. gloeosporioides. Five litres of liquid culture of the fungus produced approximately 610 mg of a mixture of secondary metabolites. Kojic acid (1) was isolated as the main secondary metabolite present in the fungal extract, and the structure was confirmed by 1D, 2D NMR and mass spectrometry. The EtOAc extract and compound 1 exhibited considerable antimicrobial activity against all tested microorganisms. Whilst the minimum inhibitory concentration (MIC) values from the EtOAc extract ranged between 2.4× 10-4 mg/mL and 2.5 mg/mL, those of kojic acid (1) were between 0.125 mg/mL and 1 mg/mL. The EtOAc extract and kojic acid (1) were most active against Pseudomonas aeruginosa (MIC = 2.4×10-4 mg/mL) and Micrococcus luteus (MIC = 0.125 mg/mL), respectively. Conclusions: The results revealed that the endophytic fungus C. gloeosporioides could be a good source of commercially important kojic acid, which exhibited antimicrobial properties