Browsing by Subject "antifungal"

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  • Mgbeahuruike, Eunice Ego; Stålnacke, Milla; Vuorela, Heikki; Holm, Yvonne (2019)
    Microbial resistance to currently available antibiotics is a public health problem in the fight against infectious diseases. Most antibiotics are characterized by numerous side effects that may be harmful to normal body cells. To improve the efficacy of these antibiotics and to find an alternative way to minimize the adverse effects associated with most conventional antibiotics, piperine and piperlongumine were screened in combination with conventional rifampicin, tetracycline, and itraconazole to evaluate their synergistic, additive, or antagonistic interactions against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans. The fractional inhibitory concentration index was used to estimate the synergistic effects of various combination ratios of the piperamides and antibiotics against the bacterial and fungal strains. Both piperine and piperlongumine showed synergistic effects against S. aureus when combined at various ratios with rifampicin. Synergistic interaction was also observed with piperine in combination with tetracycline against S. aureus, while antagonistic interaction was recorded for piperlongumine and tetracycline against S. aureus. All the piperamide/antibacterial combinations tested against P. aeruginosa showed antagonistic effects, with the exception of piperine and rifampicin, which recorded synergistic interaction at a ratio of 9:1 rifampicin/piperine. No synergistic interaction was observed when the commercial compounds were combined with itraconazole and tested against C. albicans. The results showed that piperine and piperlongumine are capable of improving the effectiveness of rifampicin and tetracycline. Dosage combinations of these bioactive compounds with the antibiotics used may be a better option for the treatment of bacterial infections that aims to minimize the adverse effects associated with the use of these conventional antibacterial drugs.
  • Amrati, Fatima Ez-Zahra; Bourhia, Mohammed; Saghrouchni, Hamza; Slighoua, Meryem; Grafov, Andriy; Ullah, Riaz; Ezzeldin, Essam; Mostafa, Gamal A.; Bari, Ahmed; Ibenmoussa, Samir; Bousta, Dalila (2021)
    Caralluma europaea (Guss.) N.E.Br.: (C. europaea) is a wild medicinal plant belonging to the family Apocynaceae. It is commonly used in traditional medicines for treating several diseases. The present work aims to evaluate the anti-inflammatory, antibacterial, and antifungal potentials of C. europaea fractions including hydro ethanol (ET CE), n-butanol (But CE), and polyphenol (Poly CE). The chemical composition of hydroethanol, n-butanol, and polyphenol-rich fractions from C. europaea were determined using GC-MS after silylation. The anti-inflammatory effect of hydroethanol, n-butanol, and polyphenol-rich fractions was studied by carrageenan-induced paw edema. Antibacterial and antifungal activities of hydroethanol, n-butanol, and polyphenol-rich fractions against Gram-positive bacteria, Gram-negative bacteria, and yeasts were assessed using the disc diffusion and micro-dilution assays. The findings of the chemical characterization affirmed the presence of interesting bioactive compounds in C. europaea fractions. The polyphenol-rich fraction was the best inhibitor of edema by75.68% after 6 h of treatment. The hydroethanol fraction was the most active against both bacteria and yeasts. This study contributes to society as it provides potential bioactive compounds in C. europaea extract, which may help in fighting nosocomial antibiotic-resistant microbes.
  • Shishido, Tania Keiko; Popin, Rafael Vicentini; Jokela, Jouni; Wahlsten, Matti; Fiore, Marli Fatima; Fewer, David P.; Herfindal, Lars; Sivonen, Kaarina (2020)
    Cyanobacteria are photosynthetic organisms that produce a large diversity of natural products with interesting bioactivities for biotechnological and pharmaceutical applications. Cyanobacterial extracts exhibit toxicity towards other microorganisms and cancer cells and, therefore, represent a source of potentially novel natural products for drug discovery. We tested 62 cyanobacterial strains isolated from various Brazilian biomes for antileukemic and antimicrobial activities. Extracts from 39 strains induced selective apoptosis in acute myeloid leukemia (AML) cancer cell lines. Five of these extracts also exhibited antifungal and antibacterial activities. Chemical and dereplication analyses revealed the production of nine known natural products. Natural products possibly responsible for the observed bioactivities and five unknown, chemically related chlorinated compounds present only in Brazilian cyanobacteria were illustrated in a molecular network. Our results provide new information on the vast biosynthetic potential of cyanobacteria isolated from Brazilian environments.
  • Heinilä, Lassi; Fewer, David; Jokela, Jouni; Wahlsten, Matti; Jortikka, Anna Elisabeth; Sivonen, Kaarina (2020)
    Cyanobacteria produce a wide range of lipopeptides that exhibit potent membrane-disrupting activities. Laxaphycins consist of two families of structurally distinct macrocyclic lipopeptides that act in a synergistic manner to produce antifungal and antiproliferative activities. Laxaphycins are produced by range of cyanobacteria but their biosynthetic origins remain unclear. Here, we identified the biosynthetic pathways responsible for the biosynthesis of the laxaphycins produced by Scytonema hofmannii PCC 7110. We show that these laxaphycins, called scytocyclamides, are produced by this cyanobacterium and are encoded in a single biosynthetic gene cluster with shared polyketide synthase enzymes initiating two distinct non-ribosomal peptide synthetase pathways. The unusual mechanism of shared enzymes synthesizing two distinct types of products may aid future research in identifying and expressing natural product biosynthetic pathways and in expanding the known biosynthetic logic of this important family of natural products.
  • Salo, Johanna; Andersson, Aino Maria Alice; Mikkola, Raimo Olavi; Kredics, Laszlo; Viljanen, Martti; Salkinoja-Salonen, Mirja Sinikka (International Society of Indoor Air Quality and Climate - ISIAQ, 2015)
    Penicillium expansum was identified as a major contaminant in indoor air, settled dust and materials of several buildings connected to indoor air related health complaints. This fungus emitted large quantities of exudates when cultivated on laboratory media. The exudates proved toxic towards four different mammalian test cells up to 10000 fold dilution. Toxins identified by LC-MS/MS were communesins and chaetoglobosin. Air dispersal of the toxic exudates was investigated with an experimental set-up where natural convection was generated by temperature gradient. It was found that the exudate with the contained toxins became airborne transported from the warmer surface to the colder surface. The results thus demonstrate transportation of microbially produced toxic substances across the air space. The role of liquid emissions from indoor molds represents a novel mechanism for human exposure in mold contaminated buildings. In this paper we report that vapor condensed from the indoor air of building affected with molds Aspergillus versicolor, Aspergillus calidoustus and Penicillium expansum contained substances that were acutely toxic when exposed to mammalian cells in vitro. The results encourage further study of condensed indoor water vapor as a tool to assess the presence of airborne substances with possible adverse health effects.