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Phthalates are plasticisers dangerous to ecosystems and humans.The paper aims to review the exposure of high-concern phthalates resulting from industrial and domestic activities to wastewater and analyse the advanced technologies used in European countries to remove phthalates from wastewater. We drew attention that many phthalates are not completely removed during the conventional wastewater treatment processes and often require an additional complex combination of technologies. Maximum wastewater cleaning efficiency (85–95%) depends on phthalates specificity and is achieved with advanced cleaning methods. However, the solutions to the problems of phthalate’s presence and removal from wastewater are often addressed at the scientific research level. Because of the modernisation and operation of advanced technologies, the cost can increase by 5–25%. As a result, some European countries face financial difficulties implementing advanced technologies. To make progress in cleaning up phthalates, the EU is likely to continue maintaining and upgrading existing wastewater systems.

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.

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.

In this paper, a portable instrument for surface tension measurements, characterization and applications is described. The instrumentation is operated wirelessly, and samples can be measured in situ. The instrument has changeable different size probes; therefore, it is possible to measure samples from 1 ml up to 10 ml. The response of the measured retraction force and the concentrations of measured surfactant is complex. Therefore, two calibration methods were proposed: (i) the conditional calibration using polynomial and logarithmic fitting and (ii) the neural network trained model prediction of the surfactant concentration in samples. Calibrating the instrument, the neural network trained model showed a superior coefficient of determination (0.999), comparing it to the conditional calibration using polynomial (0.992) and logarithmic (0.991) fit equations.

The aim of this study was to evaluate the impact of forest clear-cutting on the phenolic compounds and antiradical activity of Vaccinium myrtillus, Vaccinium vitis-idaea, and forest litter collected during the vegetation stages in 2 forests types (Pinetum vacciniosumand Pinetum vaccinio-myrtillosum). The Folin-Ciocalteu method, aluminum trichloride colorimetric assay, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) test were applied to perform the total phenolic content (TPC), total flavonoid content (TFC), and antiradical activity analyses of the extracts of the underground and aboveground parts of the plants and forest litter. The TPC content varied from 35.87 to 229.76 mg/g (expressed as rutin equivalents) and 120.03 to 309.64 mg/g in the aboveground extracts of V. myrtillus and V. vitis-idaea, respectively. Remarkably lower amounts of phenolic compounds were determined in the underground extracts of the tested shrubs. The TPC content in the forest litter ranged from 3.12 to 11.89 mg/g. The radical scavenging activity (RSA) varied from 3.12 to 434.68 mg/g; the lowest antiradical activity was determined in the underground extracts, while the highest was in the aboveground extracts of V. myrtillus. The TFC was dependent on the vegetation phase, forest type, and clear-cutting, and varied from 7.97 to 40.18 mg/g in the aboveground extracts of the tested plants. Flavonoids were not detected in the underground extracts of the samples or in the forest litter. The chemometric analysis revealed statistically significant trends of environmental impact on V. myrtillus and V. vitis-idaea at the different vegetation stages. Hypotheses testing showed that the TPC, TFC and RSA expressed statistically significant (α ≤ 0.05) changes in 68%, 60% and 71% of the tested samples after clear-cutting, respectively.

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.

Capillary electrophoresis often causes unrepeatable peak migration times in the electropherogram due to changes of electroosmosis, yet in some cases this separation technique does not have a replacement alternative. Some attempts to overcome this issue have been performed introducing internal standards into the sample and compensating peak shifting in time. However, existing vector calculation-based methods are computationally intensive for portable instrumentation and usually limited to post-processing applications with 1 or 2 markers. In this work, an original approach of compensating peak migration time shift via signal discretization period correction is proposed. Using the proposed method, the number of reference points or markers that are used for compensation is extended. This method is effective in compensating migration time of peaks in real samples, where high sample injection volumes are used. Using 4 reference peaks in compensation, the method was capable of reducing the relative standard deviation of migration time of the peaks in the electropherograms more than 15 times. Corrected signal discretization periods indicated very high correlations with recorded separation currents, what can be perspective developing an adaptive peak migration time compensation method in capillary electrophoresis.

Wooden sleepers used in railways are impregnated with preservatives with fungicidic and bactericidic properties, which contain a large amount of harmful polycyclic aromatic hydrocarbons (PAHs). The aim of this research was to reveal the type of fungi in the rhizosphere of plants, which tolerate pollutants and can be involved in bioremediation process of creosote-contaminated used wooden railway sleepers. Tagetes patula grown in the substrate with 12.5% creosote impregnated used wooden sleepers chips additive is characterized by the most intensive root development and the biggest population of active fungi, therefore it is recommended for further investigation. Number of colonies of fungi in the rhizosphere of investigated plants decreased in many cases by increasing the amount of sleepers chips additive in substrate, however it was greater in the substrates with creosote treated wooden sleepers chips additives (12.5, 25 and 37.5% wooden sleepers chips) than in the pure substrate and various substrates with additives of pure Pinus sylvestris chips. This is a pioneering study searching for the local fungi species in Lithuania, which can be further utilized for the bioremediation of PAHs.

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.

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.

The aim of this study was to perform solid-state fermentation of bee collected pollen by lactic acid bacteria and evaluate the impact of fermentation to total phenolic compounds content, total flavonoid content and radical scavenging activity of fermented and non-fermented bee pollen. Natural fermentation of bee pollen in the hive, done by bees, results in well-known product—bee bread. This study was the first attempt to produce artificial “bee bread”. To our knowledge literature date about bee pollen artificial fermentation are scarce. Five different bee pollen samples were fermented with Lactobacillus rhamnosus GG and without bacteria. Obtained fermented samples were analyzed for total phenolic compound content, total flavonoid content and free radical (DPPH) scavenging capacity by spectrophotometric methods; phenolic profile was evaluated by HPLC. Fermentation revealed positive impact on the total flavonoid content (amount of flavonoids increased by 55–135%). The results were compared with the antioxidant activity of natural bee bread. Acquired data were processed with Matlab software carrying out calculations of various similarity measures between each pollen and fermented pollen sample and bee bread sample.

Medicinal plants are reported to possess antiviral activity, but finding the substances that are responsible for antiviral activity in the complex mixture of the plant extract is an extremely difficult task. In this paper a methodology related to the determination of the antiviral properties of medicinal plant extracts and based on phytochemical analysis, antiviral tests and machine learning methods is described. 16 potentially antiviral medicinal plants were selected, and their chemometric characteristics and antiviral properties were investigated. Three different analytical methods were used for chemical analysis: (i) spectrophotometry, (ii) capillary electrophoresis with contactless conductivity detection, and (iii) gas chromatography-mass spectrometry. 14 attributes were obtained describing the composition of the plant extracts. Viral growth inhibition properties were investigated and 8 candidate plant extracts were selected as being active against viruses. Infectious bronchitis virus was used as a model virus. Machine learning techniques including deep neural network classification, classification and regression tree induction and hierarchical clusterization were used for mining the factors that are responsible for antiviral effects. It was determined that (i) phenolic compounds providing high radical scavenging activity and fractions containing high content of phenolic compounds are positively related to antiviral activity in plant extracts, (ii) hydrophilic compounds that are positively charged (pKa > 4.7) in acidic media and possess medium and low electrophoretic mobility properties are negatively related to antiviral activity in medicinal plants, (iii) phenolic acids with pKa lower than 4.7 are not related to antiviral activity in the extracts, and (iv) volatile compounds in the extracts, including diversity, quantity and different volatility properties, do not affect the antiviral activity of plant extracts. Following the proposed methodological approach, it is possible to confirm which chemometric attributes are responsible for antiviral activity in medicinal plant extracts.

This study was aimed to screen for nisin producing Lactococcus lactis strains with prominent antimicrobial and technological characteristics applicable for the dairy industry. Twelve out of 181 Lactococcus spp. strains isolated from goat and cow milk, fermented wheat and buckwheat samples were identified as L. lactis strains harbouring nisin A, Z or novel nisin variant GLc03 genes. For the first time technological characteristics of L. lactis strains harbouring nisin variant GLc03 were evaluated. All 12 isolated strains showed clear antagonistic activity against tested food spoilage and pathogenic bacteria. Moreover, strains encoding nisin Z presented favorable enzymatic activities of acid phosphatase, esterase lipase and phosphohydrolase. However, strains encoding novel nisin variant GLc03 were lacking appropriate technological characteristics being resistant to tetracycline and producing harmful β-glucosidase, therefore these strains are not applicable for the dairy food production. Two nisin A producing L. lactis strains were poor acidifiers and one strain showed resistance to tetracycline. Three strains were selected according to safety and technological criteria and were examined in fresh cheese production for control of Listeria monocytogenes growth. Listeria numbers were significantly reduced (P

E. ciliata (Lamiaceae) is very interesting and promising herb mainly for chemical composition and pharmacological activities. The aim of this study was to determine chemical composition of the essential oils of fresh, frozen and dried herbal materials of E. ciliata and compare different extraction methods This is the first study on composition of E. ciliata volatile compounds from fresh, frozen and dried herbal samples. The samples were prepared by hydrodistillation (HD), extraction with polar solvent-ethanol (ESE) and dynamic headspace solid-phase micro extraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC–MS) method. A total of 48 compounds were identified by GC–MS. Dehydroelsholtzia ketone, elsholtzia ketone, sesquiterpenes β-bourbonene, caryophyllene, α-caryophyllene, germacrene D and α-farnesene were identified and found to be predominant compounds in SPME composition of the fresh, frozen and dried herbal samples. The major amounts of ketones (dehydroelsholtzia and elsholtzia) were determined in dried herbal samples where they made up 24.94% ( p 0.05 ) and 71.34% ( p 0.05 ) of the SPME composition. Artemisia ketone was determined only in fresh herb. No previous report exists regarding this ketone in E. ciliata fresh, frozen and dried herbal materials or essential oil. There were 26 components identified in the essential oil obtained by HD. The main compounds of this essential oil were dehydroelsholtzia ketone (78.28%) and elsholtzia ketone (14.58%). Essential oil showed antiproliferative activity on three tested cancer cell lines (human glioblastoma (U87), pancreatic cancer (Panc-1) and triple negative breast cancer (MDA-MB231)) in vitro . EC 50 (half maximal effective concentration) values of essential oil against those cells were in the range of 0.017–0.021%. The viability of human normal fibroblasts exposed to the same concentrations of the essential oil was statistically significantly higher compared to the viability of cancer cells ( p 0.05 ). The extracts did not show any effect on U87 cells, and only slightly decreased MDA-MB231 cell viability (up to 76.4%) at the highest concentration of 10 mg/mL. The impact that different extraction methods have on the yield of the essential oil from the tested herbal materials requires a further research. It would enable production of pharmaceutical forms enriched by these essential oils, which are notable for their anticancer activity.

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, 75muM Cu; T2, 150muM 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.

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 0.018–0.443 mg/ml, expressed in rutin equivalents. Cell growth was analyzed after 24, 48 and 72 h 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 0.266 mg/ml caused MCF7 cells growth inhibition, while in the samples exposed to the highest concentration (0.355 and 0.443 mg/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 (0.117–0.443 mg/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 0.117 mg/ml a pronounced cell growth inhibition while at higher concentrations (0.266 and 0.443 mg/ml) no cell proliferation was observed. Conclusions The consumption of C. angustifolium herb can be advantageous, alongside with conventional breast cancer treatment.

Dominant plant species established in the understory of clear-cuts may have a strong biochemical influence on pine regeneration process, with important consequences for reforestation management. We evaluated and compared the total phenolic content and the allelopathic activity of acqueous extracts from both roots and shoots of dominant plant species established in 1-yr-old and 2-yr-old clear-cuts of Scots pine (Pinus sylvestris L.) stands in Lituania. The highest total content of phenolic compounds was detected in the lingonberry (Vaccinium vitis-idaea L.) shoots from 1-yr-old and 2-yr-old clear-cuts, as well as in the common heather (Calluna vulgaris [L.[ Hull) shoots from 1-yr-old clear-cuts. High-performance liquid chromatography (HPLC) was used to identify and quantify the allelochemicals present in the active fraction to determine their possible role in allelopathy. The highest variety and content of phenolic compounds were observed in shoot extracts of the dominant species from both 1-yr-old and 2-yr-old clear-cuts. Scots pine seed germination and seedling growth were significantly and negatively correlated with ρ-coumaric acid and sinapic acid content, while Scots pine seedling growth was significantly and negatively correlated with ferulic, caffeic and hydroxycinnamic acids contents. The highest contents of these phenolic acids were determined in aqueous extracts of C. vulgaris from 1-yr-old clear-cuts and Rumex acetosella L. of 2-yr-old clear-cuts, which exerted a strong phytotoxicity on Scots pine seed germination. Moreover, morphometric parameters of Scots pine seedlings were most sensitive to aqueous extracts of V. vitis-idaea shoots from both 1-yr-old and 2-yr-old clear-cuts and R. acetosella shoots from 2-yr-old clear-cuts.

The scientific interest for the search of natural means of microbial inhibitors has not faded for several years. A search of natural antibiotics, so-called bacteriocins which are produced by lactic acid bacteria (LAB), gains a huge attention of the scientists in the last century, in order to reduce the usage of synthetic food additives. Pure bacteriocins with wide spectra of antibacterial activity are promising among the natural biopreservatives. The usage of bacteriocin(s) producing LAB as starter culture for the fermentation of some food products, in order to increase their shelf-life, when synthetic preservatives are not allowable, is also possible. There are a lot of studies focusing on the isolation of new bacteriocins from traditional fermented food, dairy products and other foods or sometimes even from unusual non-food matrices. Bacteriocins producing bacteria have been isolated from different sources with the different antibacterial activity against food-borne microorganisms. This review covers the classification of bacteriocins, diversity of sources of bacteriocin(s) producing LAB, antibacterial spectra of isolated bacteriocins and analytical methods for the bacteriocin purification and analysis within the last 15 years.

Portable and autonomous analytical instrumentation is becoming more important. Portable instrumentation can be designed via the miniaturization approach and this is a challenging task due to: (i) the limited battery power supply, (ii) a low number of mechanical and moving parts allowed in the design and (iii) susceptibility to changing environment and temperature fluctuations. In this work we describe the design of a light emitting diode (LED) based 3D printed miniaturized colorimeter (dimensions: 5 cm × 4 cm × 4.5 cm (length, width, height), weight less than 56 g). The colorimeter was optimized for determination of the total phenolic compound content, the total flavonoid content and radical scavenging activity. The designed instrument provides comparable results to those of a conventional desktop spectrophotometer existing on the market. The designed LED based miniaturized colorimeter has wireless communication capability. This work demonstrates that this instrument can be applied investigating real samples.

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 &micro, g/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 &micro, g/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.

The development of the instrument which will significantly ease the in situ samplings of volatile compounds is described. The purpose of this work was to design an automated, portable, handheld sample collection device that operates with monolithic adsorbents. The sampler contains two lithium-ion batteries, collects samples into micro-liter range volume vials, is supplied with a changeable 100 µm inner diameter six cm long capillary with an in-tube monolithic solid-phase micro-extraction adsorbent. Modeling experiments with triethylamine and diethylamine demonstrated that instrument captured samples containing volatile substances in the range of 3.5 to 118 ppm concentration levels in the air. The substances have been analyzed using a dedicated capillary electrophoresis contactless conductivity detection system and determined amounts of volatile substances in the sample solutions ranged between 3.4 and 1010 µM. Only 0.44 mL of air was enough to adsorb substances on the adsorbent, collecting them into 50 µL of water and achieving a preconcentration effect. The developed instrument is expected to find it’s applications where sampled air or gas volume is in µL – mL range: (a) collection of volatile substances near single plant parts in vivo, (b) collection of beetle pheromones in vivo, (c) volume-restricted machinery and other related applications.

Application of selected starter cultures for sourdough propagation may ensure stable lactic acid bacteria (LAB) diversity and defined properties of sourdough that affect quality. The impact of Lactobacillus delbrueckii ssp. bulgaricus MI, L. rossiae GL14 and L. acidophilus DSM 20079 as starter cultures were investigated for spoilage prevention and whole-grain wheat and sourdough bread properties. Whole-grain wheat sourdough propagated with these strains showed high phytase, amylase and xylanases activities. The highest phytase activity was obtained in sourdough prepared with L. bulgaricus MI. The results of gas chromatography–mass spectrometry using solid-phase microextraction showed that the compositions of volatile compounds in sourdough and whole-grain wheat bread depended on the LAB starter. In bread with L. acidophilus, 3-octen-2-ol and n-hexadecane were found, whereas those compounds were not found in other bread samples or in sourdough. Tetrahydrofurfuryl acetate was found only in bread prepared with L. bulgaricus MI sourdough. N-Pentadecane was found only in bread prepared with L. rossiae sourdough and bread prepared with spontaneous sourdough. The application of thermophilic sourdough increased bread porosity, elasticity, crumbliness and moisture content, but did not influence crumb hardness. Moreover, the fungal spoilage on the bread crust surface was suppressed using sourdough prepared with thermophilic LAB. The strain of LAB used for sourdough preparation influenced the shelf-life of bread.

Five bacteriocins producing lactic acid bacteria (LAB) strains were selected to carry out the fermentation of the plants called Satureja montana L. (Sm) and Rhaponticum carthamoides (CD.) Iljin (Rc). The bioproducts obtained were applied in the production of unripened curd cheese. The total amount of LAB in plant bioproducts ranged from 7.46 to 9.42 log10 CFU/g and depended on the LAB strain and the plant species used. To reduce the possibility of biased evaluation, the acceptability of the products was assessed by using Face Reader software. Pediococcus pentosaceus KTU05-8 strain was more adaptable in the media of both plants (Sm and Rc) under both fermentation conditions: traditional submerged fermentation and solid state fermentation. The fermentation of Sm and Rc plants with LAB significantly reduced the amount of spores of mesophilic bacteria, enterobacteria, yeast and fungi. The addition of these bioproducts to unripened curd cheese reduced pH and increased the total titratable acidity, the content of volatile compounds (thymol, carvacrol, p-cymene) and the acceptability of the cheese. In comparison to the results obtained after the addition of non-fermented Sm, Lactobacillus sakei fermented bioproducts decreased the content of biogenic amines in cheese.

Fermentation of various food products leads to better nutritional value, improved biological activities, enhanced extraction properties, etc. The impact of artificial solid-state lactic acid fermentation on bee pollen properties has not been fully studied. The aim of this study was to evaluate antibacterial, antifungal and antioxidant activities of natural and pasteurized polyfloral bee pollen after spontaneous fermentation and fermentation with added Lactococcus lactis and Lactobacillus rhamnosus bacteria. Total phenolic content, total flavonoid content and radical scavenging activity increased by 1.27–2.40 times, antibacterial activity against Micrococcus luteus, Staphylococcus aureus and Escherichia coli increased by 1.08–16.9 times and antifungal activity against Penicillium roqueforti increased by 1.96–5.52 times after bee pollen fermentation. Chemometric analysis, including a similarity measure (based on Euclidean distance) estimation and self-organizing maps, were used to determine the impact of different fermentations and pasteurization on bee pollen's antioxidant and antimicrobial properties. The analysis showed that the natural microflora of the bee pollen contributes to the fermentation process together with the added bacteria, therefore pasteurized bee pollen showed significantly lower antimicrobial and antioxidant activities after fermentation than fermented natural bee pollen. Overall, the fermentation had a positive effect on bee pollen biological activities, the improvements being dependent on the botanical origin of the pollen and fermentation type (spontaneous or with added bacteria).

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) β- cis-caryophyllene, linalool, and eucalyptol possess antiviral activity, while (ii) thujones do not, and (iii) α-thujone, β-thujone, cis- p-menthan-3-one, and estragole show cytotoxic effects.

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.

The application of natural products for treatment and prevention of various diseases is becoming more important. Not only antibacterial natural preparations are being developed, but also antiviral natural products are investigated. There are two main problems in such investigations: (i) special chemical analysis and data analysis methods have to be used, (ii) not only antiviral effect has to be taken into account, but also cytotoxic and other unwanted effects. In this work, a combination of separation methods (capillary electrophoresis and gas chromatography), spectrophotometric methods, data mining/data analysis methods (hierarchical clusterization, multidimensional scaling and classification and regression tree induction) for clarifying chemical attributes in cytotoxic plant extracts was applied. The selected plants belonged to families: (i) Lamiaceae, (ii) Asteraceae and (iii) Fabaceae. Most cytotoxic were Agastache foeniculum Pursh. Kuntze. and Salvia officinalis L. extracts. Least cytotoxic were Perilla frutescens L. and Satureja Montana L. extracts. The tendency of cytotoxic extracts having abundant concentrations of medium and low electrophoretic mobility cations was clarified.

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.

The nutritional strategies to improve the quality of food products of animal origin are relatively new approach. In this work the solid state fermentation (SSF) and traditional submerged fermentation (TF) with bacteriocin-like inhibitory substances (BLIS) producing lactic acid bacteria was applied for treatment of Satureja montana L. plants (SMP). The effect of fermented SMP additives on ready-to-cook minced pork (RCMP) quality and safety was studied. Viability of LAB in SMP medium significantly (p

The studies were carried out in the period of 2013–2014 in experiment developed during plant vegetation, cultivating five plant species in the vegetative pots with the substrate contaminated with used sleepers (US) and uncontaminated substrate fertilised with nitrogenous fertilisers. The objective of the research is to analyse the morphological features of aboveground and underground parts of herbaceous plants and determine the dependence of the number of fungi and bacteria colonies in the rhizosphere of these plants and the substrate contaminants and the impact of nitrogenous fertiliser concentration; with reference to that, determine the feasibility of these plants for phytoremediation. A tolerant plant was found, i.e. Tagetes patula L. as a phytoremediator, which adapted to grow in the condition of contaminated and fertilised substrate with nitrogen, and suitable for cultivating it in similar edaphic conditions. An intolerant plant, i.e. Trifolium repens L. as a phytoindicator, is a perennial, herbaceous plant of Fabaceae Lindl. Family, the rhizosphere of which contains the maximum number of fungi and bacteria colonies in the occurrence of the maximum concentration of nitrogenous fertilisers and contaminants. These bacteriological and mycological processes, as well as the excess of nitrogen, have negative impact on the growth of aboveground and underground parts of Trifolium repens.DOI: http://dx.doi.org/10.5755/j01.erem.72.4.17493

WOS: 000406182800029, PubMed: 28732865, 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. (C) 2017 Elsevier Ltd. All rights reserved.

The capacitance-to-digital single chip detector was upgraded. The paper discusses hardware issues and benefits of the designed/upgraded detector. The device can be operated from rechargeable lithium-ion battery as stand-alone, portable system and is capable of transmitting real-time data wirelessly. The detector and additional modules (battery, battery holder, microcontroller board, wireless module) weight is less than 85 g. Electrophoretic separation in low conductivity 20 mM MES/L-His buffer, pH 6.1, was performed in order to evaluate detection parameters. The system is capable of quantification of potassium ions down to 0.31 μM. Investigation of differential signal acquisition configuration showed improved performance regarding external noise and temperature fluctuations. The system can be a solution for stand-alone, field-portable capillary format separation detector.

The aim of this study was to determine total amounts of phenolics and flavonoids, radical scavenging activities, and compositions of phenolic and volatile compounds in 14 samples of honeybee pollen collected in the Baltic region. Radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities and total amounts of phenolics and flavonoids were evaluated using spectrophotometry. Volatiles from the headspace of the samples were analyzed using solid-phase microextraction (SPME) fiber coated with 100-μm polydimethylsiloxane layer, separated, and identified employing GC-mass spectrometry (MS). Forty-two volatiles were identified in the headspace. Nonanal (1.5–20.1 %), dodecane (1.2–-34.6 %), and tridecane (1.4–24.7 %) were found in all samples. Screening of phenolics and flavonoids was performed using high-performance liquid chromatography (HPLC) with electrochemical detection. 2-Hydroxycinnamic acid (43.4–179.9 μg/g), rutin (156.2–955.7 μg/g), and quercetin (24.0–529.8 μg/g) were detected in all tested samples. Total amounts of phenolic compounds and flavonoids varied between 24.1 and 45.5 mg/g, and 6.1 and 11.6 mg/g, respectively, expressed as rutin equivalents. The pollen extracts exhibited radical scavenging activity, which scattered widely in range of 7.1–39.2 mg/g, expressed as rutin equivalents. Radical scavenging activity correlated with the total content of phenolic compounds while correlation coefficient was 0.95. Chemometric evaluation was performed to classify the samples into clusters according to the observed data.

The aim of this study was to evaluate the influence of additives of Jerusalem artichoke (JA), fermented with P. acidilactici KTU05-7, P. pentosaceus KTU05-9, L. sakei KTU05-6, on the quality and safety parameters of ready – to cook – minced pork (RCMP). Fermented JA additives reduced pH of the meat products and decreased water holding capacity (WHC) from 2.01 till 2.93 %. Concentrations of biogenic amines in RCMP with additives of the lactic acid bacteria (LAB) - fermented JA were significantly lower comparing with control sample. The number of pathogenic bacteria in artificially contaminated meat samples was significantly reduced in case of LAB-fermented JA additives. The highest antimicrobial activity was obtained using P. acidilactici fermented JA additives. The amounts of microbial pathogens E. coli and Ent. faecalis, S. aureus and Streptococcus spp. were determined 3.41, 3.38, 3,96 and 4.74 log CFU/g correspondingly, whereas without LAB-fermented JA additives were 8.94, 7.75, 8.82 and 8.58 log CFU/g, correspondingly. A possibility to improve sensory properties (flavor) of RCMP using LAB fermented JA additives was investigated. The composition of volatile compounds of RCMP without additive and with LAB-fermented JA additives was analyzed using gas chromatography–mass spectrometry (GC-MS). The results of sensory evaluation of meat products supplemented with fermented JA additives revealed specific odor, which is pleasant and acceptable for consumers might be explainable that LAB-fermented JA additives have shown considerable differences mainly due to the accumulation of volatiles such as toluene, ethylbenzene, decane, undecane, 2 methyl undecane. N-morpholinomethyl-isopropyl-sulfide, 6-undecilamine and N,N-dimethyl-1-pentadecanamine were not determined in RCMP with LAB-fermented JA additives. The results obtained show, that P. acidilactici fermented JA 5 % additive is most suitable for the RCMP processing in order to prevent microbiological spoilage, increase volatile compounds and acceptability of the products.

The aim of the study was to investigate if differences in acidification, biogenic amines (BA) and volatile compounds (VC) occurred when Lactobacillus sakei KTU05-6 , Pediococcus acidilactici KTU05-07 and Pediococcus pentosaceus KTU05-8 are used as starters in solid state fermentation of flaxseed and the impact of flaxseed sourdough on the wheat bread making process assessed. Results have shown that in SSF flaxseed with P. acidilactici and P. pentosaceus produced more acids than with L. sakei . A correlation between pH and moisture content ( R = 0.9783; P = 0.0002) and between moisture content and total titratable acidity ( R = 0.7150; P = 0.0339) was noticed. BA content in fermented flaxseed is far below those levels causing a health risk. Also, the use of lactobacillus for flaxseed fermentation has an influence on VC formation and the biggest influence on flavor formation had such compounds as: acetic acid, acetyl methyl carbinol and benzaldehyde. The main flavor component of flaxseed is ρ-cymene. Addition of fermented flaxseed to a standard wheat bread formula doesn't show big changes of the bread crumb structure. We conclude that fermentation allows to enrich wheat bread with 10% of partially defatted flaxseed without affecting the quality in a negative way.

Six samples of propolis were analyzed in the paper: a sample from Brazil, Estonia, China and three samples from different locations of Uruguay. Static headspace technique coupled with gas chromatography-mass spectrometry analysis has been applied for the determination of the characteristic volatile profile with the aim to differentiate the propolis from different regions. Monoterpenes (α- and β-pinenes) were predominant in all samples, except the sample from China. This sample separated itself by the alcohols 3-methyl-3-buten-1-ol and 3-methyl-2-buten-1-ol, (40.33% and 11.57%, respectively) and ester 4-penten-1-yl acetate (9.04%). α-Pinene and β-pinene composed 64.59–77.56% of volatiles in Brazilian and Uruguayan propolis, and 29.43% in Estonian propolis. Brazilian propolis was distinguished by a high amount of β-methyl crotonaldehyde (10.11%), one of Uruguayan samples 3- by limonene (15.58%), and the Estonian sample — by eucalyptol (25.95%). Statistical investigation of the samples was made applying principal component, hierarchical cluster and K-Means cluster analyses. Various data pre-processing techniques were proposed and used to study and obtain the important volatile compounds contributed to the differentiation of the propolis samples from different regions to separate clusters.

A capacitance-to-digital converter integrated circuit was implemented in an automated CE device as a single chip detector. In this paper, design and hardware issues related to the fabrication and application of a miniature detector for contactless measurement of complex impedance are discussed. The capacitance-to-digital converter integrated circuit was used as the whole detector. The advantage of this setup is that the single integrated circuit provides digital data and neither additional signal conditioning nor analog-to-digital converter is required. Different separation conditions were used to evaluate the detection characteristics of the constructed detection unit. A 1 μM LOD for sodium and a 1.6 μM LOD for potassium ions were revealed for the detector. The detection system designed is competitive with miniaturized contactless conductivity detectors or UV absorbance detectors with respect to overall parameters (sensitivity, resolution, power consumption properties, and size). The obtained separation and detection results show that such detection technique can be used as an extremely low power consuming and space saving solution for CE detection with potential applications in environmental monitoring, process control, and various analytical measurements.

The main aim of investigations was to identify chemotypes and determine differences between some domestic hop varieties and wild hops, which were collected from some regions of Lithuania and cultivated at the same edafoclimatic conditions in hops collection of Kaunas Botanical Garden of Vytautas Magnus University. One of objectives was to compare essential oils of hops (2 years harvest) by the evaluation of volatiles content. Among the main components of hop essential oils monoterpenes (β-myrcene) and sesquiterpenes (α-humulene and β-caryophyllene) were determined using gas chromatography coupled with mass spectrometry (GC-MS). Retention parameters (t R, calculated retention index, and Kovats retention index) and m/z value of molecular ion for selected compounds from hop essential oils were determined. Samples were prepared by applying solid phase microextraction (SPME), supercritical fluid extraction (SFE) and accelerated solvent extraction (ASE). The steam distillation was used to obtain hop essential oils. The chemometric comparison of domestic and wild hops based on GC-MS analysis data was carried out. The obtained statistical results allow us to classify the investigated wild forms and domestic varieties of hops according to the similarities of their chemotypes. The concentration of β-myrcene, α-humulene in hop essential oils obtained from cones 2 years harvests is much higher than other volatile organic compounds (15.2–23.7 % in total contribution). In analysed essential oils β-farnesene is a constituent in higher quantity of hop essential oils obtained from cones from second time harvest than from cones from first harvest. This can be explained by the year-to-year vegetation conditions difference.

Enantiomers represent a class of compounds extensively investigated since they can show totally different behaviors when they interact with a chiral environment. Because of their identical chemical structure (they differ only in the spatial arrangement of the atoms in the molecule), the separation of optical isomers is a challenging task of analytical chemistry. So far employed methods for the separation of enantiomers are mainly based on chromatography. CE as well was considered as an analytical technique suitable for chiral separations, characterized by high efficiency and low consumption of reagent. Recently, miniaturization was introduced in LC to answer the needs to perform analyses in the minimum time, to use the smallest amount of samples and to reduce environmental pollution. Nano-LC represents nowadays a valid alternative to the abovementioned conventional analytical techniques, and can be advantageously exploited for enantiomeric separation especially because it needs minute amounts of the chiral material necessary to carry out enantiomeric separations. This review describes the development and applications of nano-LC in the field of chiral separations. The data reported in literature show its relevance for the study enantiomers-chiral selectors interaction, as well as for application in pharmaceutical and clinical research.