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1.
Microorganisms ; 12(6)2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38930624

ABSTRACT

Edible fungi are a valuable resource in the search for sustainable solutions to environmental pollution. Their ability to degrade organic pollutants, extract heavy metals, and restore ecological balance has a huge potential for bioremediation. They are also sustainable food resources. Edible fungi (basidiomycetes or fungi from other divisions) represent an underutilized resource in the field of bioremediation. By maximizing their unique capabilities, it is possible to develop innovative approaches for addressing environmental contamination. The aim of the present study was to find selective chemical agents suppressing the growth of microfungi and bacteria, but not suppressing white-rot fungi, in order to perform large-scale cultivation of white-rot fungi in natural unsterile substrates and use it for different purposes. One application could be the preparation of a matrix composed of wooden sleeper (contaminated with PAHs) and soil for further hazardous waste bioremediation using white-rot fungi. In vitro microbiological methods were applied, such as, firstly, compatibility tests between bacteria and white-rot fungi or microfungi, allowing us to evaluate the interaction between different organisms, and secondly, the addition of chemicals on the surface of a Petri dish with a test strain of microorganisms of white-rot fungi, allowing us to determine the impact of chemicals on the growth of organisms. This study shows that white-rot fungi are not compatible to grow with several rhizobacteria or bacteria isolated from soil and bioremediated waste. Therefore, the impact of several inorganic materials, such as lime (hydrated form), charcoal, dolomite powder, ash, gypsum, phosphogypsum, hydrogen peroxide, potassium permanganate, and sodium hydroxide, was evaluated on the growth of microfungi (sixteen strains), white-rot fungi (three strains), and bacteria (nine strains) in vitro. Charcoal, dolomite powder, gypsum, and phosphogypsum did not suppress the growth either of microfungi or of bacteria in the tested substrate, and even acted as promoters of their growth. The effects of the other agents tested were strain dependent. Potassium permanganate could be used for bacteria and Candida spp. growth suppression, but not for other microfungi. Lime showed promising results by suppressing the growth of microfungi and bacteria, but it also suppressed the growth of white-rot fungi. Hydrogen peroxide showed strong suppression of microfungi, and even had a bactericidal effect on some bacteria, but did not have an impact on white-rot fungi. The study highlights the practical utility of using hydrogen peroxide up to 3% as an effective biota-suppressing chemical agent prior to inoculating white-rot fungi in the large-scale bioremediation of polluted substrates, or in the large-scale cultivation for mushroom production as a foodstuff.

2.
Foods ; 12(19)2023 Sep 26.
Article in English | MEDLINE | ID: mdl-37835235

ABSTRACT

Bee pollen is one of the most valuable apitherapeutic products with high nutritional value. To obtain a higher diversity of compounds, higher bioactivity, and improve the release of nutrients from bee pollen, additional processing of the raw material may be applied: fermentation using microorganisms or hydrolysis using selective enzymes. This research aimed to determine the impact of enzymatic hydrolysis on the antioxidant and antibacterial activities of bee pollen. Bee pollen samples from Sweden, Spain, Netherlands, Italy, Poland, Denmark, Slovakia, Malta, and Lithuania were hydrolyzed using pure enzymes, including lipase, cellulase, protease, and amyloglucosidase, as well as enzyme mixtures such as Viscozyme® L and Clara-diastase. Total phenolic content, total flavonoid content, and antioxidant activity were analyzed spectrophotometrically. Antibacterial activity against Staphylococcus aureus, Listeria monocytogenes, Staphylococcus enteritidis, and Salmonella typhimurium was evaluated using the agar well diffusion assay. Obtained results revealed a positive effect of enzymatic hydrolysis on biologically active compound content and activity: total phenolic content increased by 1.1 to 2.5 times, total flavonoid content by 1.1 to 3.0 times, radical scavenging activity by 1.1-3.5 times, and antibacterial activity by 1.1 to 3.3 times. K-means clustering analysis grouped samples into 5-9 clusters and was dependent on the measured characteristic used as an input-total phenolic compounds content, total flavonoid content, antioxidant activity, and antibacterial activity against four different bacteria. Chemometrics showed, that the enzyme used for the hydrolysis had a higher impact on clustering results than the geographical origin of the samples.

3.
Appl Bionics Biomech ; 2022: 9411024, 2022.
Article in English | MEDLINE | ID: mdl-36245929

ABSTRACT

Regenerative medicine is a fast expanding scientific topic. One of the main areas of development directions in this field is the usage of additive manufacturing to fabricate functional components that would be later integrated directly into the human body. One such structure could be a microfluidic valve which could replace its biological counterpart in veins as it is worn out over the lifetime of a patient. In this work, we explore the possibility to produce such a structure by using multiphoton polymerization (MPP). This technology allows the creation of 3D structures on a micro- and nanometric scale. In this work, the fabrication of microfluidic systems by direct laser writing was carried out. These devices consist of a 100 µm diameter channel and within it a 200 µm long three-dimensional one-way mechanical valve. The idea of this device is to have a single flow direction for a fluid. For testing purposes, the valve was integrated into a femtosecond laser-made glass microfluidic system. Such a system acts as a platform for testing such small and delicate devices. Measurements of the dimensions of the device within such a testing platform were taken and the repeatability of this process was analyzed. The capability to use it for flow direction control is measured. Possible implications to the field of regenerative medicine are discussed.

4.
Molecules ; 27(9)2022 Apr 22.
Article in English | MEDLINE | ID: mdl-35566057

ABSTRACT

This work involves a comprehensive chemical composition analysis of leaf and cone samples of Lithuanian hop varieties. This study aimed to determine the chemometric properties of the leaves and cones of five Lithuanian hop varieties. Determined properties were the following: (a) xanthohumol content, (b) phenolic compounds, (c) flavonoids, (d) radical scavenging activity, and (e) the qualitative composition of volatile compounds. The total content of phenolic compounds in aqueous 75% methanolic extracts varied between 31.4-78.2 mg of rutin equivalents (RE)/g, and the concentration of flavonoids was between 11.0-23.3 mg RE/g. Radical scavenging activity varied between 34.4-87.2 mg RE/g. A QUENCHER analysis procedure showed 91.7-168.5 mg RE/g of the total phenolic compound content, 12.7-21.4 mg RE/g of flavonoids, and 48.4-121.0 mg RE/g of radical scavenging activity. 'Fredos taurieji' and 'Fredos derlingieji' varieties have shown maximum values of phenolic compounds and radical scavenging activity both in leaf and cone suspensions. These varieties accumulated a higher amount of xanthohumol in leaves. The concentration of xanthohumol in the samples varied between 0.0014-0.2136% of dry mass, with the highest concentration in the cones of 'Kauno grazieji'. We identified 19 volatile compounds in leaves, and in cones, we identified 32. In both of them, α-humulene and ß caryophyllene dominated. 'Raudoniai' leaves were exceptional in their aroma due to dominating compound nagina ketone (Kovats index 1306). The QUENCHER procedure has shown a great potential for the unextractable residue of hop raw material. Further investigation and valorization of different hop biomass components, not only cones, are essential.


Subject(s)
Humulus , Flavonoids , Humulus/chemistry , Lithuania , Plant Extracts/chemistry , Plant Leaves/chemistry
5.
Antioxidants (Basel) ; 11(4)2022 Mar 28.
Article in English | MEDLINE | ID: mdl-35453330

ABSTRACT

Bee-collected pollen is one of the most valuable natural products. However, the pollen cell walls limit the digestibility and release of nutrients to the human body. Solid-state lactic acid fermentation can be used to ease the release of bioactive compounds from the pollen cell. The aim of this research was to determine the impact of a solid-state lactic acid fermentation process on biologically active compound composition and antioxidant activity of bee-collected pollen from various European regions (Italy, Netherlands, Lithuania, Poland, Sweden, Denmark, Malta, Slovakia, and Spain). Spontaneous fermentation and fermentation using an L. rhamnosus culture were performed. The total content of phenolic compounds, total content of flavonoids, and radical (DPPH) scavenging activity were measured by spectrophotometric tests, while UPLC was employed for quantification of phenolic compounds. The determined fermentation positive effects included an increase of total phenolic content by 1.4-2.3 times, total flavonoid content by 1.1-1.6 times, and radical scavenging activity by 1.4-2.3 times. Naringenin (21.09-135.03 µg/g), quercetin (6.62-78.86 µg/g), luteolin (29.41-88.90 µg/g), and rutin (21.40-89.93 µg/g) were the most abundant flavonoids in all samples; however, their variation level was both geographical in origin and fermentation-type dependent. Fermentation increased the content of phenolic acids with high antioxidant potentials such as ellagic, ferulic and caffeic, while reduction of chlorogenic acid was determined.

6.
ACS Omega ; 6(22): 14612-14620, 2021 Jun 08.
Article in English | MEDLINE | ID: mdl-34124484

ABSTRACT

Unknown extraction recovery from solid matrix samples leads to meaningless chemical analysis results. It cannot always be determined, and it depends on the complexity of the matrix and properties of the extracted substances. This paper combines a mathematical model with the machine learning method-neural networks that predict liquid extraction recovery from solid matrices. The prediction of the three-stage extraction recovery of polycyclic aromatic hydrocarbons from a wooden railway sleeper matrix is demonstrated. Calculation of the extraction recovery requires the extract's volume to be measured and the polycyclic aromatic hydrocarbons' concentration to be determined for each stage. These data are used to calculate the input values for a neural network model. Lowest mean-squared error (0.014) and smallest retraining relative standard deviation (20.7%) were achieved with the neural network setup 6:5:5:4:1 (six inputs, three hidden layers with five, five, and four neurons in a layer, and one output). To train such a neural network, it took less than 8000 steps-less than a second--using an average-performance laptop. The relative standard deviation of the extraction recovery predictions ranged between 1.13 and 5.15%. The three-stage recovery of the extracted dry sample showed 104% of three different polycyclic aromatic hydrocarbons. The extracted wet sample recovery was 71, 98, and 55% for phenanthrene, anthracene, and pyrene, respectively. This method is applicable in the environmental, food processing, pharmaceutical, biochemical, biotechnology, and space research areas where extraction should be performed autonomously without human interference.

7.
Antioxidants (Basel) ; 10(1)2021 Jan 05.
Article in English | MEDLINE | ID: mdl-33466256

ABSTRACT

Satureja hortensis L. is an annual herbaceous plant of the Lamiaceae Lindl. family. S. hortensis L., related to thyme and rosemary, is used as spice and traditional medicinal herb in Europe. Mainly due to the polyphenols contained in S. hortensis L., this plant exhibits multiple biological effects. However, therapeutic effects on cells, including skin tumors, have not yet been studied. Therefore, the aim of this study was to compare the composition and the resulting antioxidant as well as biological properties [on melanocytes and melanoma cells] of summer, savory growing in botanical garden of Vytautas Magnus University in middle Lithuania climatic conditions, collected during various phases of vegetation. It has been shown that the budding phase alcohol extract of this plant contains the largest amounts of polyphenols, including rutin and rosemary acid, which promote the radical scavenging activity and antioxidant properties. In contrast, the extract from the massive flowering phase already at a concentration of 12.5 µg/mL reduces the survival of melanoma cells to 60% with 90% melanocytes survival. In addition, extracts from beginning of flowering and end of flowering at a concentration of 25 µg/mL, containing significantly less rutin and rosmarinic acid, in combination with irradiation of cells with UVB, significantly increased the lipid peroxidation process, particularly in melanoma cells. These data indicate the possibility of using extracts from S. hortensis L. to modulate/differentiate the metabolism of normal and tumor skin cells.

8.
Anal Methods ; 13(1): 141-146, 2021 01 07.
Article in English | MEDLINE | ID: mdl-33320117

ABSTRACT

In this work, the design and characterization of a multi-cell capacitively coupled contactless conductivity detection system are described. The operation and simultaneous acquisition from 3 detector cells are demonstrated, however, the system is capable of supplying 8 detection cells and can be easily upgraded to maintain 64 capacitively coupled contactless conductivity detection cells. On performing flow-injection analysis, the system recorded as low as 0.01 mM of acetic acid, phosphoric acid, NaH2PO4, and Na2B4O7 solutions in water. The instrument was also capable of recording and distinguishing different mixtures of organic solvents: (a) methanol-acetonitrile, (b) hexane-acetone. The designed detection system is expected to be used coupled with multi-channel separation devices for monitoring simultaneous processes.

9.
Anal Methods ; 12(41): 4977-4986, 2020 11 07.
Article in English | MEDLINE | ID: mdl-33006341

ABSTRACT

Hazardous remote places exist in the world. Why should health or life be risked sending a scientist to the investigation site, as the remote analytical instrumentation exists? Different scientific fields require instruments that could be used on-site (in situ), therefore the purpose of this work was to design a fully automated chemical analysis system small enough to be mountable on a drone. Here we show an autonomous analytical system with sampling capability on a drone. The system is suited for the remote and autonomous analysis of volatile and non-volatile chemicals in the air. The designed system weighs less than 800 g. Data are transmitted wirelessly. Collected substances are separated automatically without the intervention of the operator using the method of capillary zone electrophoresis. The analytes are detected using a miniaturized contactless conductivity detector quantifying them down to less than 1 µM. In this work, we demonstrated sampling and separation of volatile amines (triethylamine and diethylamine) and organic acids (acetic and formic acids), non-volatile inorganic cations (K+, Ca2+, Na+), and protein (bovine serum albumin) in the aerosol state. It was shown that the capillary electrophoretic analysis can be performed on a hovering drone. We anticipate our work to be a starting point for more sophisticated, autonomous complex sample analysis. We believe that our designed instrument will enable the investigation of hazardous places in different research fields.

10.
Biomolecules ; 9(12)2019 12 03.
Article in English | MEDLINE | ID: mdl-31816969

ABSTRACT

The aim of this study was to compare the physichochemical composition of various bee products, namely, bee pollen, beebread, propolis, honey, and royal jelly. The samples (37 out of 53) were collected in Lithuania, several samples from other Europe countries (Italy, Denmark, Sweden, Slovakia, Poland, Spain, Republic of Malta, The Netherlands, Latvia, Ukraine) were used for comparison. Various quantities, such as pH, electrical conductivity, oxidation-reduction potential, NaCl content, refraction index, Brix value, total phenolic compound content, total flavonoid content and antiradical activity were measured. Together with the mentioned, the content of micro- and macroelements (As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Se, Sr, V and Zn), ultraviolet-visible spectroscopy absorption spectra were analysed. To our knowledge, the literature data about comprehensive comparison of various characteristics of bee products are scarce. Also, to the best of our knowledge, this is the first study revealing mineral content in Lithuanian bee pollen, beebread and royal jelly. The study exposed that bee pollen not only showed the highest values of pH, electrical conductivity and content of soluble solids, but also distinguished from the other samples by the highest flavonoid content (up to 48.3 mg/10 g), the absence of Cr, the presence of Co (0.011-0.100 mg/kg) and Sr (0.73-5.37 mg/kg) and the highest content of Ca (997-2455 mg/kg) and Mg (644-1004 mg/kg). Hierarchical clustering analysis was applied to group the tested samples according to the physicochemical analysis results and mineral content. The clustering analysis revealed that bee pollen formed separate group with the highest distance from the other samples in both cases.


Subject(s)
Bees/physiology , Fatty Acids/chemistry , Honey/analysis , Pollen/chemistry , Propolis/chemistry , Animals , Deep Learning , Europe , Hydrogen-Ion Concentration , Spectrum Analysis
11.
BMC Vet Res ; 15(1): 178, 2019 May 29.
Article in English | MEDLINE | ID: mdl-31142304

ABSTRACT

BACKGROUND: Avian infectious bronchitis (IB) is a disease that can result in huge economic losses in the poultry industry. The high level of mutations of the IB virus (IBV) leads to the emergence of new serotypes and genotypes, and limits the efficacy of routine prevention. Medicinal plants, or substances derived from them, are being tested as options in the prevention of infectious diseases such as IB in many countries. The objective of this study was to investigate extracts of 15 selected medicinal plants for anti-IBV activity. RESULTS: Extracts of S. montana, O. vulgare, M. piperita, M. officinalis, T. vulgaris, H. officinalis, S. officinalis and D. canadense showed anti-IBV activity prior to and during infection, while S. montana showed activity prior to and after infection. M. piperita, O. vulgare and T. vulgaris extracts had > 60 SI. In further studies no virus plaques (plaque reduction rate 100%) or cytopathogenic effect (decrease of TCID50 from 2.0 to 5.0 log10) were detected after IBV treatment with extracts of M. piperita, D. canadense and T. vulgaris at concentrations of extracts ≥0.25 cytotoxic concentration (CC50) (P < 0.05). Both PFU number and TCID50 increased after the use of M. piperita, D. canadense, T. vulgaris and M. officinalis extracts, the concentrations of which were 0.125 CC50 and 0.25 CC50 (P < 0.05). Real-time PCR detected IBV RNA after treatment with all plant extracts using concentrations of 1:2 CC50, 1:4 CC50 and 1:8 CC50. Delta cycle threshold (Ct) values decreased significantly comparing Ct values of 1:2 CC50 and 1:8 CC50 dilutions (P < 0.05). CONCLUSIONS: Many extracts of plants acted against IBV prior to and during infection, but the most effective were those of M. piperita, T. vulgaris and D. canadense .


Subject(s)
Antiviral Agents/pharmacology , Infectious bronchitis virus/drug effects , Plant Extracts/pharmacology , Plants, Medicinal , Animals , Antiviral Agents/toxicity , Chlorocebus aethiops , Microbial Sensitivity Tests , Plant Extracts/toxicity , Real-Time Polymerase Chain Reaction , Vero Cells , Viral Plaque Assay
12.
Food Chem ; 289: 16-25, 2019 Aug 15.
Article in English | MEDLINE | ID: mdl-30955598

ABSTRACT

The aim of this study was to evaluate chemical and biological potential of garden cress (Lepidium sativum L.) to receive valuable plant extracts with potential application in pharmacy or food industry. Four techniques of extraction and three environmentally friendly solvents such as water, supercritical CO2 and ethanol have been tested. Biological activity and chemical profile were evaluated in obtained extracts. GC/MS analysis showed that SFE extract from dried sprouts of L. sativum was especially rich in such glucosinolate derivatives as benzyl cyanide and benzyl thiocyanate. However, the extract obtained from freeze-dried sprouts by SFE with addition of 96% ethanol as co-solvent was especially rich in flavonoids and simultaneously exhibited the best antimicrobial activity. Comparison of MALDI-TOF-MS spectra of all obtained extracts clearly indicates that both SFE and maceration with water are the most selective techniques of extraction due to the lowest level of interfering substances with high molecular masses.


Subject(s)
Lepidium sativum/chemistry , Plant Extracts/chemistry , Solvents/chemistry , Acetonitriles/analysis , Animals , Anti-Infective Agents/chemistry , Anti-Infective Agents/isolation & purification , Anti-Infective Agents/pharmacology , Cell Line , Cell Survival/drug effects , Chromatography, Supercritical Fluid , Ethanol/chemistry , Flavonoids/chemistry , Flavonoids/isolation & purification , Freeze Drying , Gas Chromatography-Mass Spectrometry , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Lepidium sativum/metabolism , Plant Extracts/pharmacology , Rats , Thiocyanates/analysis , Water/chemistry
13.
Anal Chem ; 91(1): 1080-1088, 2019 01 02.
Article in English | MEDLINE | ID: mdl-30488694

ABSTRACT

The methodology described in this article will significantly reduce the time required for understanding the relations between chromatographic data and bioactivity assays. The methodology is a hybrid of hypothesis-based and data-driven scientific approaches. In this work, a novel chromatographic data segmentation method is proposed, which demonstrates the capability of finding what volatile substances are responsible for antiviral and cytotoxic effects in the medicinal plant extracts. Up until now, the full potential of the separation methods has not been exploited in the life sciences. This was due to the lack of data ordering methods capable of adequately preparing the chromatographic information. Furthermore, the data analysis methods suffer from multidimensionality, requiring a large number of investigated data points. A new method is described for processing any chromatographic information into a vector. The obtained vectors of highly complex and different origin samples can be compared mathematically. The proposed method, efficient with relatively small sized data sets, does not suffer from multidimensionality. In this novel analytical approach, the samples did not need fractionation and purification, which is typically used in hypothesis-based scientific research. All investigations were performed using crude extracts possessing hundreds of phyto-substances. The antiviral properties of medicinal plant extracts were investigated using gas chromatography-mass spectrometry, antiviral tests, and proposed data analysis methods. The findings suggested that (i) ß- cis-caryophyllene, linalool, and eucalyptol possess antiviral activity, while (ii) thujones do not, and (iii) α-thujone, ß-thujone, cis- p-menthan-3-one, and estragole show cytotoxic effects.


Subject(s)
Antiviral Agents/analysis , Plant Extracts/chemistry , Plants, Medicinal/chemistry , Volatile Organic Compounds/analysis , Animals , Antiviral Agents/pharmacology , Cell Survival/drug effects , Chlorocebus aethiops , Gas Chromatography-Mass Spectrometry , Infectious bronchitis virus/drug effects , Microbial Sensitivity Tests , Plant Extracts/pharmacology , Vero Cells , Virus Replication/drug effects , Volatile Organic Compounds/pharmacology
14.
Probiotics Antimicrob Proteins ; 11(2): 713-722, 2019 06.
Article in English | MEDLINE | ID: mdl-30027473

ABSTRACT

The main task of the present study was to evaluate an impact of three nisin Z-producing Lactococcus lactis bacteria newly isolated from raw goat milk for some fresh cow cheese characteristics during the storage. Microbiological evaluation for Listeria monocytogenes, Staphylococcus aureus, and viable lactic acid bacteria counts and determination of pH, titratable acidity, and lactic acid concentration of produced cheese were performed after 0, 24, 48, 72, and 96 h. Sensory analysis for the evaluation of acidity, flavor intensity, color intensity, bitterness, and crumbliness of prepared cheese was performed. The changes of volatile compounds in fresh cheese were evaluated using headspace solid phase microextraction (SPME) coupled with gas chromatography-mass spectrometry. Chemometric methods were applied for the data analysis. Study showed that tested bacteria are suitable for the manufacturing of fresh cheese and possible application for fresh cheese biopreservation, as pathogenic bacteria did not grow during 4 days (96 h); chemometric analysis revealed that L. lactis strain LL56 was the most similar to commercially available L. lactis ATCC11454.


Subject(s)
Cheese/microbiology , Lactococcus lactis/metabolism , Nisin/analogs & derivatives , Animals , Cheese/analysis , Hemolysis , Lactococcus lactis/pathogenicity , Milk/microbiology , Nisin/biosynthesis , Virulence Factors
15.
Electrophoresis ; 39(22): 2877-2883, 2018 11.
Article in English | MEDLINE | ID: mdl-29935006

ABSTRACT

One of the main problems of the remote complex sample analysis instrumentation is that such systems are susceptible to temperature fluctuations. Temperature regulation is energetically ineffective, and it is not used in most of the field portable analytical systems. Separations performed in a changing temperature environment provide electropherograms with considerable baseline fluctuations, resulting in significant errors in detection and integration of the peaks. This paper describes electropherogram baseline compensation that is suitable for the capillary electrophoresis-contactless conductivity detection analytical method. The baseline compensation utilizes linear or polynomial data processing methods, and can be programmed in-line using simple microcontroller, or on-line and off-line in data acquisition software. This method is targeted for field portable and autonomous analytical systems that are utilized in a fluctuating environment.


Subject(s)
Electrophoresis, Capillary/instrumentation , Signal Processing, Computer-Assisted , Temperature , Algorithms , Electric Conductivity , Electrophoresis, Capillary/methods , Equipment Design
16.
Electrophoresis ; 39(19): 2425-2430, 2018 10.
Article in English | MEDLINE | ID: mdl-29935020

ABSTRACT

Determination of natural preservatives using electrophoretic or chromatographic techniques in fermented milk products is a complex task due to the following reasons: (i) the concentrations of the analytes can be below the detection limits, (ii) complex matrix and comigrating/coeluting compounds in the sample can interfere with the analytes of the interest, (iii) low recovery of the analytes, and (iv) the necessity of complex sample preparation. The aim of this study was to apply capillary zone electrophoresis coupled with contactless conductivity detection for the separation and determination of nisin in fermented milk products. In this work, separation and determination of natural preservative-nisin in fermented milk products is described. Optimized conditions using capillary zone electrophoresis coupled with capacitance-to-digital technology based contactless conductivity detector and data conditioning, which filter the noise of the electropherogram adaptively to the peak migration time, allowed precise, accurate, sensitive (limit of quantification: 0.02 µg/mL), and most importantly requiring very minute sample preparation, determination of nisin. Sample preparation includes following steps: (i) extraction/dilution and (ii) centrifugation. This method was applied for the determination of nisin in real samples, i.e. fermented milk products. The values of different nisin forms were ranging from 0.056 ± 0.003 µg/mL to 9.307 ± 0.437 µg/g.


Subject(s)
Cheese/analysis , Electrophoresis, Capillary/methods , Nisin/analysis , Electric Conductivity , Limit of Detection , Reproducibility of Results
17.
Anal Chem ; 90(11): 6773-6780, 2018 06 05.
Article in English | MEDLINE | ID: mdl-29708731

ABSTRACT

In the present work, we demonstrate a novel approach to improve the sensitivity of the "out of lab" portable capillary electrophoretic measurements. Nowadays, many signal enhancement methods are (i) underused (nonoptimal), (ii) overused (distorts the data), or (iii) inapplicable in field-portable instrumentation because of a lack of computational power. The described innovative migration velocity-adaptive moving average method uses an optimal averaging window size and can be easily implemented with a microcontroller. The contactless conductivity detection was used as a model for the development of a signal processing method and the demonstration of its impact on the sensitivity. The frequency characteristics of the recorded electropherograms and peaks were clarified. Higher electrophoretic mobility analytes exhibit higher-frequency peaks, whereas lower electrophoretic mobility analytes exhibit lower-frequency peaks. On the basis of the obtained data, a migration velocity-adaptive moving average algorithm was created, adapted, and programmed into capillary electrophoresis data-processing software. Employing the developed algorithm, each data point is processed depending on a certain migration time of the analyte. Because of the implemented migration velocity-adaptive moving average method, the signal-to-noise ratio improved up to 11 times for sampling frequency of 4.6 Hz and up to 22 times for sampling frequency of 25 Hz. This paper could potentially be used as a methodological guideline for the development of new smoothing algorithms that require adaptive conditions in capillary electrophoresis and other separation methods.

18.
Carbohydr Polym ; 173: 269-275, 2017 Oct 01.
Article in English | MEDLINE | ID: mdl-28732865

ABSTRACT

The kiwi fruit, Actinidia kolomikta, has valuable properties such as high antioxidant activity, high vitamin C, polyphenols, chlorophylls and organic acids content, but the species are hardly commercialized due to their short shelf life (less than two days). In this study three different cultivars of A. kolomikta (Anyksta, Sentiabrskaya and VIR2) were coated with low, medium and high molecular weight chitosan bio-polymer with the aim to extend the shelf life. The changes in fruit firmness, mass, phenolic compound content, vitamin C content and subjective criteria (withering level, decoloration level and aesthetic appearance) were monitored. It was observed that high molecular weight chitosan had higher positive effect on the shelf life of Sentiabrskaya and Anyksta cultivars than VIR2. Low molecular weight chitosan was found effective on VIR2.


Subject(s)
Actinidia , Chitosan/chemistry , Food Storage , Fruit , Ascorbic Acid/analysis , Molecular Weight , Phenols/analysis
19.
Sci Total Environ ; 592: 412-418, 2017 Aug 15.
Article in English | MEDLINE | ID: mdl-28334619

ABSTRACT

A serious concern for the environmental and human health is represented by the increasing copper (Cu) occurrence in agricultural soils and waters, because of the possible food contamination and bioaugmentation along the trophic chain. The request for the decontamination of different matrices with an environmentally sustainable technology as the phytoremediation should be addressed by selecting plant materials with improved pollutant tolerance and removal capability. With this purpose, plants of the hybrid poplar clone "Monviso" (Populus×generosa A. Henry×P. nigra L.) were grown in growth chamber under hydroponics and exposed to excess Cu concentrations (T1, 75µM Cu; T2, 150µM Cu), selected as about 5 and 10 times higher than those allowed by the Italian regulation on water use. Results evidenced a notable Cu tolerance by poplar plants, particularly at the lowest Cu concentration. At organ level, the root system was the most affected by Cu treatment, especially in T2-exposed plants. Copper determinations revealed that the metal was mostly bioaccumulated in the roots, with a limited amount reaching the shoots. Chlorophyll content and fluorescence analyses confirmed the visible symptoms in leaves, highlighting a good physiological status in T1-exposed plants. Contrarily, an impairment of the main processes associated to photosynthesis was observed in T2-exposed plants also by gas exchange measurements. Remarkably, the Cu content analysis of the spiked water solutions revealed that poplar plants succeeded in removing almost the 50% of the total Cu amount added. These results strengthen the evidence that poplar plants represent a useful eco-friendly bio-tool for the decontamination of metal polluted waters.


Subject(s)
Biodegradation, Environmental , Copper/isolation & purification , Populus/metabolism , Water Purification , Metals , Plant Roots/metabolism , Wastewater
20.
Adv Med Sci ; 62(1): 158-164, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28282602

ABSTRACT

PURPOSE: To evaluate the antiproliferative effect of the aerial part of Chamerion angustifolium (L.) Holub. (Onagraceae) extract and its fractions in vitro. This is the first study on the anti-proliferative effect of C. angustifolium on 3 distinct breast cancer cell lines. MATERIAL/METHODS: Breast cancer cell lines MCF7, MDA-MB-468 and MDA-MB-231 were exposed to different concentrations of the water extract of C. angustifolium, where DPPH radical scavenging activity was 0.018-0.443mg/ml, expressed in rutin equivalents. Cell growth was analyzed after 24, 48 and 72h of incubation. Solid-phase extraction was applied for the fractionation of C. angustifolium water extract and MDA-MB-468 cell line growth was tested using different fractions. RESULTS: The concentrations corresponding to radical scavenging activity of 0.117 and 0.266mg/ml caused MCF7 cells growth inhibition, while in the samples exposed to the highest concentration (0.355 and 0.443mg/ml) no proliferation was register, suggesting cell death. MDA-MB-468 cell analysis showed similar responses. MDA-MB-231 demonstrated cell growth inhibition following the exposure to all analyzed high extract doses (0.117-0.443mg/ml). MDA-MB-468 cells were selected to evaluate the effect of fractions. In the samples exposed to the fraction containing the highest amount (91%) of oenothein B, at the concentration of 0.117mg/ml a pronounced cell growth inhibition while at higher concentrations (0.266 and 0.443mg/ml) no cell proliferation was observed. CONCLUSIONS: The consumption of C. angustifolium herb can be advantageous, alongside with conventional breast cancer treatment.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Cell Proliferation/drug effects , Flavonoids/pharmacology , Onagraceae/chemistry , Phytotherapy , Plant Extracts/pharmacology , Apoptosis/drug effects , Female , Humans , Tumor Cells, Cultured
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