Effects of a cold atmospheric pressure plasma (CAPP) treatment on the germination, production of biomass, vigor of seedlings, uptake of water of wheat seeds (
Triticum aestivum
L. cv. Eva) were ...investigated. The CAPP treatment influence on the inactivation of microorganisms occurring on the surface of wheat seeds was investigated also. The so-called Diffuse Coplanar Surface Barrier Discharge generating a cold plasma in ambient air with high power volume density of some 100 W/cm
3
was used for the treatment of seeds at exposure times in the range of 10–600 s. The optical emission spectroscopy and the electrical measurements were used for estimation of CAPP parameters. The obtained results indicate that the germination rate, dry weight and vigor of seedlings significantly increased for plasma treatment from 20 to 50 s. The plasma treatment of seeds led to an extensive increase in wettability and faster germination comparing with the untreated seeds. The growth inhibition effect of CAPP on the surface microflora of wheat seeds increased with the increase of the treatment time. The efficiency of the treatment of wheat seeds artificially contaminated with pure cultures of filamentous fungi decreased in the following order:
Fusarium nivale
>
F
.
culmorum
>
Trichothecium roseum
>
Aspergillus flavus
>
A. clavatus
.
The article deals with comparative study of antimicrobial efficiency of metallurgical slags suitable for construction applications. The tested slags were as follows: granulated blast-furnace slag ...(GS1), air cooled blast-furnace slag (AS2), demetallized steel slag (DS3), calcerous ladle slag (LS4), slag from copper refining (CS5). The antimicrobial activity was tested on selected representatives of bacteria, yeasts, and filamentous fungi. The highest antibacterial activity possessed LS4, which intensely inhibited growth of bacteria with the lowest concentration of slag (10%) in the growth media. 100% inhibition of growth of some bacteria was observed only in slags LS4, DS3 and AS2 in concentrations 20% - 60% of slag. Antibacterial activity of slag samples was decreasing in the order: LS4 > DS3 > AS2 > GS1 > CS5. Growth of all model yeasts was 100% inhibited at as low concentration as 20% of slag GS1 and DS3, and 10% of slag LS4. Antiyeast activity of slags was decreasing in the order: LS4 > GS1 = DS3 > AS2 > CS5. Regarding that filamentous fungi were selectively sensitive to presence of slags, it is possible to determine only approximate order of inhibition effectiveness of slags to fungi: LS4 > GS1 = DS3 > AS2 = CS5.
The interaction of a copper complexes containing Schiff bases with calf thymus (CT) DNA was investigated by spectroscopic methods. UV–vis, fluorescence and CD spectroscopies were conducted to assess ...their binding ability with CT DNA. The binding constants
K have been estimated from 0.8 to 9.1
×
10
4
M
−1. The percentage of hypochromism is found to be over 70% (from spectral titrations). The results showed that the copper(II) complexes could bind to DNA with an intercalative mode. Synergic action of Cu(II) complexes with ascorbic acid against
Candida albicans induced the generation of free radicals and increased (more than 60 times) antimicrobial effect of these complexes.
Trinuclear Ag(I) (1) and dinuclear and mononuclear Zn(II) isonicotinate (2 and 3) complexes were prepared and characterized by X-ray crystallography, elemental analysis, IR spectroscopy, and thermal ...analysis. Single-crystal analysis of the Ag(I) complex reveals two different monodentate carboxylate coordination modes, protonated and deprotonated, respectively. IR spectra showed correlations between isonicotinate coordination modes and Δ(ν
as
− ν
s
)
IR
values. In addition, the hydrogen bonds significantly influence a position of carboxylate absorption bands. Moreover, IC
50
and MIC data for bacteria, yeasts, and filamentous fungi were determined and the binding of Ag(I) and Zn(II) complexes to calf thymus DNA was investigated using electronic absorption, fluorescence, and CD measurements. Biological tests showed that the Ag(I) complex is more active than commercially used Ag(I) sulfadiazine against Escherichia coli. The fluorescence spectral results indicate that the complexes can bind to DNA through an intercalative mode. The Stern-Volmer quenching constants for investigated complexes obtained from the linear quenching plot are in the range of 1.67 × 10
4
-3.42 × 10
4
M
−1
.
Silver(I) pyridinecarboxylates (AgPIC (1), AgNIC (2), Ag(HDIPIC)·0.75H
2
O (3), PIC = picolinate, NIC = nicotinate, HDIPIC = dipicolinate) were prepared by solvothermal syntheses and their ...characterization were completed by elemental, spectral, and thermal analyses. To assign the pyridinecarboxylate coordination mode in the complexes, detailed mid-infrared spectral data and Δ(ν
as
− ν
s
) comparisons were accomplished. In addition, silver(I) pyridinecarboxylate antimicrobial activities and stability by
1
H NMR spectra were determined. Moreover, the spectral, thermal, and antimicrobial properties of silver(I) and previously prepared zinc(II) pyridinecarboxylates were compared and discussed.
Cytotoxic/cytostatic activity of N-salicylidene-L-glutamato diaqua copper(II) complex (CuC) against mice leukemia cells L1210 has been estimated and their bioactivity was enhanced by addition of ...ascorbic acid. The Cu-complex with isoquinoline ligand (IQ-CuC) had stronger cytostatic effect (IC50 =15.6 microM) than parental complex (CuC) and its cytotoxicity several times increased in the presence of 0.1 mM ascorbic acid (IC50 =1.0 microM). The cytotoxicity has been caused by oxidative stress, enhanced creation of TBARS has been confirmed, and formation of 2',7'-dichlorofluorescein from 2',7'- dichlorodihydrofluorescein has been observed, also. Some hallmarks of apoptotic/necrotic death of L1210 cells have been observed by fluorescent microscopy after dyeing of cell with propidium iodide and Hoechst 33342. In addition, it was confirmed that both complexes in the presence of ascorbic acid cleavaged of pDNA. Although these copper complexes were initially prepared as substances with antioxidant properties we have showed that combined treatment of L1210 cells with IQCuC and ascorbic acid induced strong oxidative stress and death of cells. Our results confirmed that physiological concentration of ascorbic acid increases the cytostatic/cytotoxic efficiency of N-salicylidene-L-glutamato diaqua copper(II) complexes.
Application of UV radiation to the strain
Trichoderma
sp. T-bt (isolated from lignite) resulted in the T-brm mutant which was resistant to the systemic fungicide benomyl. The
tub2
gene sequence in ...the T-brm mutant differed from the parent as well as the collection strain (replacing tyrosine with histidine in the TUB2 protein). Under
in vitro
conditions this mutant exhibited a higher mycoparasitic activity toward phytopathogenic fungi.
The different dialkyl and diaryl diselenides with carbamoyl and sulfamoyl moieties
2,
3,
5 and other substituents in the
ortho position of benzene ring
4,
7,
8 as well as derivatives of ...1,2,4-benzoselenadiazine (
6) were designed as antiviral and antimicrobial agents and synthesized. Some of them, particularly
8a and
8b, were found in the antiviral assay in vitro to be strong inhibitors of cytopathic activity encephalomyocarditis virus (EMCV). The compound
4a and
8a were found to have a broad spectrum of acivity against bacteria, yeasts and pathogenic fungi in vitro.
Microorganisms were isolated from lignite freshly excavated in the Záhorie coal mine (southwestern Slovakia) under conditions excluding contamination with either soil or air-borne microorganisms. The ...isolates represented both Prokarya and Eukarya (fungi). All were able to grow on standard media, although some microorganisms were unstable and became extinct during storage of coal samples. Bacteria belonged to the genera
Bacillus,
Staphylococcus, and
Rhodococcus, according to both morphological criteria and ITS sequences. Several bacterial isolates were resistant to antibiotics. The presence of anaerobic bacteria was also documented, although they have not yet been identified. Fungal isolates were typified by using their ITS sequences. They belonged to the genera
Trichoderma (
Hypocrea),
Penicillium,
Epicoccum,
Metarhizium (
Cordyceps), and
Cladosporium. Several fungi produced compounds with antibiotic action against standard bacterial strains. The evidence for the presence of microorganisms in native lignite was obtained by means of fluorescence microscopy, scanning electron microscopy, and electron microprobe analysis. Results demonstrated that microorganisms were able to survive in the low-rank coal over a long time period.
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