Arrayan and peumo fruits are commonly used in the traditional medicine of Chile. In this study, the concentration of the extracts halving the bacterial viability and biofilms formation and disruption of the drug-sensitive and drug-resistant strains of Staphylococcus aureus and Pseudomonas aeruginosa was determined. The chemical composition of extracts was analyzed by high-resolution liquid chromatography coupled with mass spectrometry (U-HPLC/MS). The arrayan extract (Inhibitory concentration IC50 0.35 ± 0.01 mg/mL) was more effective than peumo extract (IC50 0.53 ± 0.02 mg/mL) in the inhibition of S. aureus planktonic cells. Similarly, the arrayan extract was more effective in inhibiting the adhesion (S. aureus IC50 0.23 ± 0.02 mg/mL, P. aeruginosa IC50 0.29 ± 0.02 mg/mL) than peumo extracts (S. aureus IC50 0.47 ± 0.03 mg/mL, P. aeruginosa IC50 0.35 ± 0.01 mg/mL). Both extracts inhibited quorum sensing in a concentration-dependent manner, and the most significant was the autoinducer-2 type communication inhibition by arrayan extract. Both extracts also disrupted preformed biofilm of P. aeruginosa (arrayan IC50 0.56 ± 0.04 mg/mL, peumo IC50 0.59 ± 0.04 mg/mL). However, neither arrayan nor peumo extracts disrupted S. aureus mature biofilm. U-HPLC/MS showed that both fruit extracts mainly possessed quercetin compounds; the peumo fruit extract also contained phenolic acids and phenylpropanoids. Our results suggested that both extracts could be used as natural antimicrobials for some skin and nosocomial infections.
- Publikační typ
- časopisecké články MeSH
Numerous in vitro assays are used to characterize the antioxidant properties of natural-based matrices. However, many of them generate contradictory and non-compliant results. In our study, we focused on the characterization of traditionally used biochemical (2,2'-azino-bis-(3-ethylbenzothiazoline-6 sulfonic acid) (ABTS), Oxygen Radical Absorption Capacity (ORAC), and 2,2-diphenyl-1-picrylhydrazyl (DPPH)) and cellular (CAA) antioxidant tests on a broad set of milk thistle dietary supplements containing silymarin. In addition to 26 commercially available preparations, also the natural silymarin extract available from Sigma Aldrich, St. Louis, MI, USA, and a model mixture of pure flavonoid/flavonolignans mimicking the silymarin composition were investigated as control samples. Significant differences in the antioxidant capacity of the supplements were observed. Unlike the DPPH, the results of the ABTS and ORAC methods correlated with the silymarin components determined by U-HPLC-HRMS/MS. The responses in CAA were considerably lower than in other assays. Silymarin exhibited a significantly higher antioxidant capacity than the artificially prepared flavonoid/flavonolignans mixture in all tests, indicating possible presence of other antioxidants of natural origin. The follow-up U-HPLC-HRMS/MS screening revealed the presence of tens of non-silymarin compounds with reported antioxidant activity (not only in the silymarin extract, but also in the milk thistle preparations). The sum of the total phenolics and the sum of the simple phenolics correlated with CAA results more than silymarin.
- Publikační typ
- časopisecké články MeSH
Silychristin A is the second most abundant compound of silymarin. Silymarin complex was previously described as an antioxidant with multidrug resistance modulation activity. Here, the results of a classical biochemical antioxidant assay (ORAC) were compared with a cellular assay evaluating the antioxidant capacity of pure silychristin A and its derivatives (anhydrosilychristin, isosilychristin and 2,3-dehydrosilychristin A). All the tested compounds acted as antioxidants within the cells, but 2,3-dehydro- and anhydro derivatives were almost twice as potent as the other tested compounds. Similar results were obtained in LPS-stimulated macrophages, where 2,3-dehydro- and anhydrosilychristin inhibited NO production nearly twice as efficiently as silychristin A. The inhibition of P-glycoprotein (P-gp) was determined in vitro, and the respective sensitization of doxorubicin-resistant ovarian carcinoma overproducing P-gp was detected. Despite the fact that the inhibition of P-gp was demonstrated in a concentration-dependent manner for each tested compound, the sensitization of the resistant cell line was observed predominantly for silychristin A and 2,3-dehydrosilychristin A. However, anhydrosilychristin and isosilychristin affected the expression of both the P-gp (ABCB1) and ABCG2 genes. This is the first report showing that silychristin A and its 2,3-dehydro-derivative modulate multidrug resistance by the direct inhibition of P-gp, in contrast to anhydrosilychristin and isosilychristin modulating multidrug resistance by downregulating the expression of the dominant transmembrane efflux pumps.
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Although many genetic manipulations of crops providing biofortified or safer food have been done, the acceptance of biotechnology crops still remains limited. We report on a transgenic barley expressing the multi-functional protein osmotin that improves plant defense under stress conditions. METHODS: An Agrobacterium-mediated technique was used to transform immature embryos of the spring barley cultivar Golden Promise. Transgenic barley plants of the T0 and T1 generation were evaluated by molecular methods. Transgenic barley tolerance to stress was determined by chlorophyll, total protein, malondialdehyde and ascorbate peroxidase content. Methanol extracts of i) Fusarium oxysporum infected or ii) salt-stressed plants, were characterized by their acute toxicity effect on human dermal fibroblasts (HDF), genotoxicity and affection of biodiversity interactions, which was tested through monitoring barley natural virus pathogen-host interactions-the BYDV and WDV viruses transmitted to the plants by aphids and leafhoppers. RESULTS: Transgenic plants maintained the same level of chlorophyll and protein, which significantly declined in wild-type barley under the same stressful conditions. Salt stress evoked higher ascorbate peroxidase level and correspondingly less malondialdehyde. Osmotin expressing barley extracts exhibited a lower cytotoxicity effect of statistical significance than that of wild-type plants under both types of stress tested on human dermal fibroblasts. Extract of Fusarium oxysporum infected transgenic barley was not able to damage DNA in the Comet assay, which is in opposite to control plants. Moreover, this particular barley did not affect the local biodiversity. CONCLUSION: Our findings provide a new perspective that could help to evaluate the safety of products from genetically modified crops.
- MeSH
- bezpečnost potravin * MeSH
- biologická adaptace MeSH
- ektopická exprese * MeSH
- fyziologický stres genetika MeSH
- geneticky modifikované rostliny MeSH
- interakce hostitele a patogenu genetika MeSH
- ječmen (rod) genetika MeSH
- lidé MeSH
- rekombinantní proteiny * MeSH
- rostlinné proteiny genetika MeSH
- tabák genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The first described small non-coding RNA was microRNA lin-4 from Caenorhabditis elegans in 1993. This miRNA has begun a new age of research leading to the discovery of previously unknown, endogenous, single stranded, 22–25 nucleotides long molecules regulating nearly 30 % of genes. Recently, it was demonstrated that a number of organic substances presented in the diet induces the formation of various miRNAs. Besides this, plant and animal miRNA may enter the host organisms as food. In host organism, they can resist degradation and can enter the bloodstream. Although lacking sufficient experimental support, the discussion whether such dietary miRNAs can participate in post-transcriptional regulation of host genes is an actual topic. Either of these mechanisms could also explain some of the biological activities of medicinal plants. Non-coding RNAs have also significance as diagnostic biomarkers of some diseases or as targets for complex disease therapies.
- MeSH
- biologické markery metabolismus MeSH
- genetická transkripce genetika imunologie MeSH
- iniciace genetické transkripce MeSH
- lidé MeSH
- mikro RNA izolace a purifikace metabolismus MeSH
- nekódující RNA * genetika izolace a purifikace metabolismus MeSH
- potraviny MeSH
- regulace genové exprese u nádorů genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
The osmotin protein is involved in both monocot and dicot plant responses to biotic and abiotic stress. To determine the biological activity of osmotin, the gene was amplified from tobacco genomic DNA, fused with the hexahistidine tag motif and successfully expressed in Escherichia coli, after which the recombinant osmotin was purified and renatured. Various activities were then tested, including hemolytic activity, toxicity against human embryonic kidney cells, and the antifungal activity of the recombinant osmotin. We found that osmotin had no adverse effects on human kidney cells up to a concentration of 500 μg.ml(-)(1). However, the purified osmotin also had significant antimicrobial activity, specifically against fungal pathogens causing candidiasis and otitis, and against the common food pathogens. Using the osmotin-Agrobacterium construct, the osmotin gene was inserted into tobacco plants in order to facilitate the isolation of recombinant protein. Using qPCR, the presence and copy number of the transgene was detected in the tobacco plant DNA. The transgene was also quantified using mRNA, and results indicated a strong expression profile, however the native protein has been never isolated. Once the transgene presence was confirmed, the transgenic tobacco plants were grown in high saline concentrations and monitored for seed germination and chlorophyll content as indicators of overall plant health. Results indicated that the transgenic tobacco plants had a higher tolerance for osmotic stress. These results indicate that the osmotin gene has the potential to increase crop tolerance to stresses such as fungal attack and unfavorable osmotic conditions.
- MeSH
- geneticky modifikované rostliny * genetika růst a vývoj metabolismus MeSH
- halotolerantní rostliny * genetika růst a vývoj metabolismus MeSH
- lidé MeSH
- rostlinné proteiny * biosyntéza genetika MeSH
- tabák * genetika růst a vývoj metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Although stinging nettle (Urtica dioica) has been shown to reduce HM (heavy metal) content in soil, its wider phytoremediation potential has been neglected. Urtica dioica was cultivated in soils contaminated with HMs or polychlorinated biphenyls (PCBs). After four months, up to 33% of the less chlorinated biphenyls and 8% of HMs (Zn, Pb, Cd) had been removed. Bacteria were isolated from the plant tissue, with the endophytic bacteria Bacillus shackletonii and Streptomyces badius shown to have the most significant effect. These bacteria demonstrated not only benefits for plant growth, but also extreme tolerance to As, Zn and Pb. Despite these results, the native phytoremediation potential of nettles could be improved by biotechnologies. Transient expression was used to investigate the functionality of the most common constitutive promoter, CaMV 35S in Urtica dioica. This showed the expression of the CUP and bphC transgenes. Collectively, our findings suggest that remediation by stinging nettle could have a much wider range of applications than previously thought.
- MeSH
- biodegradace * MeSH
- genetické inženýrství metody MeSH
- geneticky modifikované rostliny genetika metabolismus MeSH
- kadmium metabolismus MeSH
- látky znečišťující půdu metabolismus MeSH
- olovo metabolismus MeSH
- polychlorované bifenyly analýza metabolismus MeSH
- promotorové oblasti (genetika) * genetika MeSH
- půda chemie MeSH
- regulace genové exprese u rostlin genetika MeSH
- těžké kovy analýza metabolismus MeSH
- Urtica dioica genetika metabolismus MeSH
- zinek metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
Geneticky modifikované rostliny mohou být velmi účinnou alternativou k odstraněni různých nebezpečných organických i anorganických polutantů. Tato xenobiotika isou obvykle perzistentní a toxické povahy, často jsou jen velmi obtížné odstranitelná z životního prostředí. Přenos bakteriálních degradačních genů do rostlin může pomoci úspěšné a účinnější tytoremediaci. To se již potvrdilo řadou uskutečněných přenosů. Tento článek shrnuje geneticky modifikované rostliny, které již byly připraveny a bylo u nich prokázáno odbourávání či akumulace xenobiotika a vyšší životaschopnost na toxickém substrátu ve srovnání s netransgenními liniemi.
Genetically modified plants can serve as highly efficient alternative for degradation of various dangerous organic as well as inorganic pollutants. These compounds are persistent toxic xenobiotics difficult to destroy or removal from the environment. The transfer of bacterial degradation genes into plant genome may help to successfull and efficient phytoremediation. It has been confirmed by transfer o1 the various genes. The article summarizes genetically modified plants, which were already prepared and where the degradation activity or accumulation of xenobiotic compounds and higher viability in the presence of toxic substrate was determinated.
