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1.
BMC Plant Biol ; 23(1): 486, 2023 Oct 11.
Article in English | MEDLINE | ID: mdl-37821804

ABSTRACT

BACKGROUND: Microbial communities have occasionally been observed in part of the ephemeric reproductive structure of floral stigmas, but their prevalence, phylogenetic diversity and ecological roles are understudied. This report describes the first study of bacterial and fungal communities in immature and mature stigma tissue of the endangered holoparasitic plant Phelipanche arenaria. Culture-dependent methods coupled with next-generation sequencing indicated that a small surface of the flower stigma was an unexpectedly rich and diverse microhabitat for colonization of microbial. We also compared the enzymatic activity of the bacterial communities between immature and mature stigmas samples. RESULTS: Using high-throughput sequencing methods, we identified and classified 39 to over 51 OTUs per sample for bacterial OTUs represented by Pantoea agglomerans and P. ananatis, comprising 50.6%, followed by Pseudomonas, Luteibacter spp., Sphingomonas spp. with 17% of total frequency. The bacterial profile of immature stigmas of P. arenaria contained unique microorganisms (21 of the most numerous OTUs) that were not confirmed in mature stigmas. However, the enzymatic activity of bacteria in mature stigmas of P. arenaria showed more activity than observed in immature stigmas. In the fungal profile, we recorded even 80 OTUs in mature stigmas, consisting of Capnodiales 45.03% of the total abundance with 28.27% of frequency was created by Alternaria eichhorniae (10.55%), Mycosphaerella tassiana (9.69%), and Aureobasidium pullulans (8.03%). Additionally, numerous putative plant growth-promoting bacteria, fungal pathogens and pathogen-antagonistic yeasts were also detected. CONCLUSIONS: Our study uncovered that P. arenaria stigmas host diverse bacterial and fungal communities. These microorganisms are well known and have been described as beneficial for biotechnological and environmental applications (e.g., production of different enzymes and antimicrobial compounds). This research provided valuable insight into the parasitic plant-microbe interactions.


Subject(s)
Microbiota , Orobanchaceae , Phylogeny , Bacteria , Flowers
2.
Molecules ; 28(12)2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37375422

ABSTRACT

The simplest way to eliminate microorganisms in the must/wine is through sulfuration, as it allows the introduction of pure yeast varieties into the must, which guarantees a high-quality wine. However, sulfur is an allergen, and an increasing number of people are developing allergies to it. Therefore, alternative methods for microbiological stabilization of must and wine are being sought. Consequently, the aim of the experiment was to evaluate the effectiveness of ionizing radiation in eliminating microorganisms in must. The sensitivity of wine yeasts, Saccharomyces cerevisiae, S. cerevisiae var. bayanus, Brettanomyces bruxellensis, and wild yeasts to ionizing radiation was com-pared. The effects of these yeasts on wine chemistry and quality were also determined. Ionizing radiation eliminates yeast in wine. A dose of 2.5 kGy reduced the amount of yeast by more than 90% without reducing the quality of the wine. However, higher doses of radiation worsened the organoleptic properties of the wine. The breed of yeast used has a very strong influence on the quality of the wine. It is justifiable to use commercial yeast breeds to obtain standard-quality wine. The use of special strains, e.g., B. bruxellensis, is also justified when aiming to obtain a unique product during vinification. This wine was reminiscent of wine produced with wild yeast.. The wine fermented with wild yeast had a very poor chemical composition, which negatively affected its taste and aroma. The high content of 2-methylbutanol and 3-methylbutanol caused the wine to have a nail polish remover smell.


Subject(s)
Saccharomyces cerevisiae , Wine , Humans , Wine/analysis , Food Microbiology , Fermentation , Plant Breeding , Allergens
3.
J Speech Lang Hear Res ; 64(9): 3603-3616, 2021 09 14.
Article in English | MEDLINE | ID: mdl-34403288

ABSTRACT

Purpose The acoustic source that is attended to by the listener in a mixture can be identified with a certain accuracy on the basis of their neural response recorded during listening, and various phenomena may be used to detect attention. For example, neural tracking (NT) and alpha power lateralization (APL) may be utilized in order to obtain information concerning attention. However, these methods of auditory attention detection (AAD) are typically tested in different experimental setups, which makes it impossible to compare their accuracy. The aim of this study is to compare the accuracy of AAD based on NT, APL, and their combination for a dichotic natural speech listening task. Method Thirteen adult listeners were presented with dichotic speech stimuli and instructed to attend to one of them. Electroencephalogram of the subjects was continuously recorded during the experiment using a set of 32 active electrodes. The accuracy of AAD was evaluated for trial lengths of 50, 25, and 12.5 s. AAD was tested for various parameters of NT- and APL-based modules. Results The obtained results suggest that NT of natural running speech provides similar accuracy to APL. The statistically significant improvement of the accuracy of AAD using a combined method has been observed not only for the longest duration of test samples (50 s, p = .005) but also for shorter ones (25 s, p = .011). Conclusions It seems that the combination of standard NT and APL significantly increases the effectiveness of accurate identification of the traced signal perceived by a listener under dichotic conditions. It has been demonstrated that, under certain conditions, the combination of NT and APL may provide a benefit for AAD in cocktail party scenarios.


Subject(s)
Speech Perception , Acoustic Stimulation , Adult , Attention , Auditory Perception , Electroencephalography , Humans , Speech
4.
Sci Rep ; 10(1): 16696, 2020 10 07.
Article in English | MEDLINE | ID: mdl-33028946

ABSTRACT

The aim of this study was to compare the nutritional and use value of berries grown in organic and conventional systems. The polyphenol content, fruit colour and firmness, and yeast, mould, and mycotoxin contents were assessed in blueberry fruit freshly harvested and stored for 8 weeks in controlled conditions (CA: CO2-12%; O2-1.5%, temperature 1.5 °C). The Shannon-Wiener diversity index was comparable in both systems and was lower for mould in organic fruit than in conventional fruit. Mycotoxins (deoxynivalenol, zearalenone) were found only in organic fruits. The optimal mineral content and pH of the soil allowed the cultivation of blueberry in accordance with organic standards. The storage of highbush blueberry fruit in CA cold storage for 8 weeks resulted in a slight deterioration in fruit quality and polyphenol content. The lower nutritional value of these fruits is compensated by the lack of pesticides and artificial fertilizers residues. The use of fungicides in conventional cultivation reduces the population of sensitive fungi and therefore reduces the contamination of fruits with mycotoxins.


Subject(s)
Blueberry Plants/microbiology , Fruit/microbiology , Fungi/isolation & purification , Plant Diseases/microbiology , Blueberry Plants/physiology , Food Preservation/methods
5.
Sci Total Environ ; 716: 137071, 2020 May 10.
Article in English | MEDLINE | ID: mdl-32069695

ABSTRACT

The holoparasitic genus Cistanche (Orobanchaceae) has been the most widely used and well known genus in traditional Chinese medicine for centuries. This is the first study that reports the phytochemical profile of Cistanche armena - an endemic species from Armenia and evaluates the composition and biological activity in relation to specific organs of the parasite (flowers vs stem with tuber) and its interaction with two host species: Alhagi maurorum (Fabaceae) and Salsola dendroides (Chenopodiaceae). We identified polyphenolic compounds using the UPLC-PDA-MS/MS method and quantified the antioxidative effects; inhibitory activities; polyphenol, nitrate III and nitrate V contents; ABTS+, DPPH, and FRAP activities; and colour parameters. A total of 28 polyphenolic compounds were tentatively identified. In C. armena, 9 compounds belonged to the phenylethanoid glycosides, mainly acteoside, B-hydroxyverbascoside and echinacoside, and in its hosts, 19 compounds belonged mainly to hydroxycinnamic acid and the flavanols. The profile of polyphenols in the host species was qualitatively and quantitatively different than the profile of the compounds in the parasite; this indicates the existence of a unique pathway of compound biosynthesis in the parasite. The colour and the amount and bioactivity of the polyphenolic compounds found in Cistanche were very diverse and depended on both the host plant and their location (organs) in the parasite. The stem and tuber of Cistanche hosted by Salsola had the highest polyphenol content, which was approximately 4 times higher than that in the stem and flowers of Cistanche individuals that parasitized A. maurorum. In addition, the stem and tuber of Cistanche that parasitized S. dendroides was characterized by the highest antioxidant activity (ABTS+, DPPH and FRAP) and high inhibitory activities. Conversely, the amount of polyphenols in the host Alhagi was 12 times higher than that in S. dendroides. These results highlight the importance of C. armena as a promising source of functional and bioactive ingredients (harvested from potential cultivation, not from natural endangered localities) and also draws the attention of future researchers to an important aspect regarding the parasite organ and the host's influence on the harvested material of various parasitic herbs.


Subject(s)
Cistanche , Armenia , Host-Parasite Interactions , Phytochemicals , Tandem Mass Spectrometry
6.
Molecules ; 24(18)2019 Sep 19.
Article in English | MEDLINE | ID: mdl-31546827

ABSTRACT

Potassium metabisulphite is usually used for microbial stabilization in the process of vinification and wine preservation, but it is considered to be allergenic. The objective of the present study was to assess the efficiency of ozonation and ionizing radiation as alternatives to wine sulphurization. The efficiency of yeast removal and the retention of the chemical quality of wine were evaluated. Wine was subjected to 60 min of ozonation, and radiation doses were set at 1-10 kGy. Moreover, a combination of ozonation and ionizing radiation treatment was used. The ozonation of wine did not produce the expected results. That is, it did not limit the number of yeast cells. From the sixth minute, a significant deterioration in the taste and the color of the wine was found. Ionizing radiation at a dose of 1 kGy reduced the yeast count by 95.5%, and a reduction of 99.9% was seen after the application of 2.5 kGy. Moreover, these doses did not have a significant effect on the organoleptic properties or the chemical composition of wine. The total amount of polyphenols reduced from the maximum of 1127.15 to 1023.73 mg at the dose of 5 kGy. Radiation is widely used to preserve food products. Its use for finished wine preservation may be an alternative to sulphurization.


Subject(s)
Electrons , Food Preservation , Ozone/chemistry , Sulfur/chemistry , Wine/analysis , Microbial Viability/drug effects , Sensation , Sulfites/pharmacology , Time Factors , Wine/microbiology , Yeasts/drug effects
7.
Vascular ; 23(2): 154-60, 2015 Apr.
Article in English | MEDLINE | ID: mdl-24966273

ABSTRACT

OBJECTIVES: The main purpose of this study was to document the radiation doses to patients during carotid stenting. MATERIAL AND METHOD: Fluoroscopy and exposure time, air kerma and dose-area product during carotid artery stenting in 160 patients were retrospectively reviewed with regard to body mass index, degree of stenosis and use of cerebral protection devices. RESULTS: Total air kerma was lower than 0.5 Gy in 80%, 0.5-1 Gy in 17% and higher than 1 Gy (maximum 1.2) in 3% of patients. Mean total dose-area product value for carotid stenting was 54 Gy cm(2). The mean air kerma (fluoroscopy), air kerma (exposure), total air kerma and dose-area product (fluoroscopy), dose-area product (exposure), total dose-area product of patients with body mass index within the range 25-29.9 and with body mass index >30 were significantly increased compared to that of patients with body mass index 18-24.9 (H = 40.2, df = 2; p = 0.0000001 and p = 0.000003, respectively). CONCLUSION: Carotid artery stenting is a relatively safe radiological procedure in terms of the radiation dose acquired by the patient. The main factors contributing to possible radiation overdosing are body mass index value and complexity of the carotid lesion. Proper preoperative planning in obese and complicated patients may reduce the fluoroscopy time and contribute to reduced dose acquisition.


Subject(s)
Carotid Artery, Common/surgery , Radiation Dosage , Radiation Exposure , Radiography, Interventional , Stents , Adult , Aged , Aged, 80 and over , Female , Fluoroscopy/methods , Humans , Male , Middle Aged , Radiography, Interventional/methods , Retrospective Studies
8.
Med Sci Monit ; 17(11): MT97-103, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22037751

ABSTRACT

BACKGROUND: An important negative factor of EVAR is the radiation acquired during long-lasting procedures. The aim of the study was to document the radiation doses of EVAR and to discuss potential reasons for prolongation of radiological procedures. MATERIAL/METHODS: Dose-area product (DAP) (Gy cm²) and air kerma (AK) (Gy) obtained during EVAR from 92 patients were analyzed retrospectively in regards to body mass index (BMI), angulations of aneurysm neck, length of aneurysm neck and occurrence of tortuosity of iliac arteries. RESULTS: Total AK for fluoroscopy differed significantly between normal BMI (373 mGy) and BMI 25-29.9 (1125 mGy) or BMI >30 (1085 mGy). Iliac artery tortuosities >45° and short aneurysm necks caused higher doses of total AK (1097 mGy and 1228 mGy, respectively) than iliac artery tortuosities <45° and long aneurysm necks (605 mGy and 720 mGy, respectively). CONCLUSIONS: The main factors contributing to a high radiation dose being acquired by patients during EVAR are: BMI >25, tortuosity of iliac arteries >45° and short aneurysm necks.


Subject(s)
Angiography, Digital Subtraction/adverse effects , Aortic Aneurysm, Abdominal/surgery , Blood Vessel Prosthesis Implantation/methods , Fluoroscopy/adverse effects , Radiation Dosage , Radiography, Interventional/adverse effects , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Statistics, Nonparametric , Time Factors
9.
Water Air Soil Pollut ; 220(1-4): 373-385, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21949452

ABSTRACT

The capability of environmental microorganisms to biodegrade simazine-an active substance of 2-chloro-s-triazine herbicides (pesticide waste since 2007)-was assessed. An enormous metabolic potential of microorganisms impels to explore the possibilities of using them as an alternative way for thermal and chemical methods of utilization. First, the biotope rich in microorganisms resistant to simazine was examined. Only the higher dose of simazine (100 mg/l) had an actual influence on quantity of bacteria and environmental fungi incubated on substrate with simazine. Most simazine-resistant bacteria populated activated sludge and biohumus (vermicompost); the biggest strain of resistant fungi was found in floral soil and risosphere soil of maize. Compost and biohumus were the sources of microorganisms which biodegraded simazine, though either of them was the dominant considering the quantity of simazine-resistant microorganisms. In both cases of periodic culture (microorganisms from biohumus and compost), nearly 100% of simazine (50 mg/l) was degraded (within 8 days). After the repeated enrichment culture with simazine, the rate of its degradation highly accelerated, and just after 24 h, the significant decrease of simazine (20% in compost and 80% in biohumus) was noted. Although a dozen attempts of isolating various strains responsible for biodegradation of simazine from compost and biohumus were performed, only the strain identified as Arthrobacter urefaciens (NC) was obtained, and it biodegraded simazine with almost 100% efficiency (within 4 days).

10.
Pol J Radiol ; 76(4): 60-2, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22802857

ABSTRACT

This study is a case report regarding a possible problem of high radiation dose during stent-graft implantation. Before deciding on how to treat an aneurysm (stent grafting or traditional surgery), possible complications such as difficult anatomical conditions and diseases of the aorta and iliac arteries should be considered to avoid potentially high doses of radiation. In case of this patient, it was very difficult to introduce a guidewire through the contralateral limb into the body of the graft due to tortuosity and kinking of iliac arteries. Because of the long duration of the procedure (68 min), the patient was exposed to a very high radiation dose (4.37 Gy) and DAP (1760.3 Gy cm(2)).

11.
Hear Res ; 269(1-2): 162-8, 2010 Oct 01.
Article in English | MEDLINE | ID: mdl-20603206

ABSTRACT

This study assessed the effects of speech misidentification and cognitive processing errors in normal-hearing adults listening to degraded auditory input signals simulating cochlear implants in reverberation conditions. Three variables were controlled: number of vocoder channels (six and twelve), instantaneous frequency change rate (none, 50, 400 Hz), and enclosures (different reverberation conditions). The analyses were made on the basis of: (a) nonsense word recognition scores for eight young normal-hearing listeners, (b) 'ease of listening' based on the time of response, and (c) the subjective measure of difficulty. The maximum score of speech intelligibility in cochlear implant simulation was 70% for non-reverberant conditions with a 12-channel vocoder and changes of instantaneous frequency limited to 400 Hz. In the presence of reflections, word misidentification was about 10-20 percentage points higher. There was little difference between the 50 and 400 Hz frequency modulation cut-off for the 12-channel vocoder; however, in the case of six channels this difference was more significant. The results of the experiment suggest that the information other than F0, that is carried by FM, can be sufficient to improve speech intelligibility in the real-world conditions.


Subject(s)
Auditory Perception/physiology , Cochlear Implants , Deafness/physiopathology , Speech Perception/physiology , Animals , Auditory Threshold/physiology , Deafness/therapy , Electric Stimulation Therapy , Evoked Potentials, Auditory, Brain Stem/physiology , Female , Guinea Pigs , Models, Animal , Reaction Time/physiology , Spiral Ganglion/cytology , Spiral Ganglion/physiology
12.
J Speech Lang Hear Res ; 52(4): 945-55, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19380609

ABSTRACT

PURPOSE: To study the perceptual consequences of changes in parameters of vocoded speech in various reverberation conditions. METHOD: The 3 controlled variables were number of vocoder bands, instantaneous frequency change rate, and reverberation conditions. The effects were quantified in terms of (a) nonsense words' recognition scores for young normal-hearing listeners, (b) ease of listening based on the time of response (response delay), and (c) the subjective measure of difficulty (10-degree scale). RESULTS: It has been shown that the fine structure of a signal is a relevant cue in speech perception in reverberation conditions. The results obtained for different number of bands, frequency-modulation cutoff frequencies, and reverberation conditions have shown that all these parameters are important for speech perception in reverberation. CONCLUSIONS: Only slow variations in the instantaneous frequency (<50 Hz) seem to play a critical role in speech intelligibility in anechoic conditions. In reverberant enclosures, however, fast fluctuations of instantaneous frequency are also significant.


Subject(s)
Speech Acoustics , Speech Perception , Speech , Acoustic Stimulation , Adult , Analysis of Variance , Humans , Psychoacoustics , Reaction Time , Young Adult
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