The Influence of Convective, Microwave Vacuum and Microwave-Assisted Drying on Blueberry Pomace Physicochemical Properties

The effect of hot air convective drying (HACD), microwave-vacuum drying (MWVD) and combined drying (HACD + MWVD) on the drying kinetics, bioactive compounds and color of blueberry pomace was evaluated. Drying time of blueberry pomace ranged from 0.6 to 6.7 h and moisture diffusion coefficients ranged from 7.94 × 10–8 to 1.83 × 10–7 m2/s. Drying caused degradation of total polyphenolics (TP) (39–76%), monomeric anthocyanins (21–77%) and antioxidant capacity values (24–76%). Drying time was shortened even by 91%, when MWVD was used instead of HACD. MWVD of blueberry pomace resulted in the smallest, while HACD at 60°C in the greatest loss of bioactive compounds and antioxidant capacity. HACD at 60°C + MWVD allowed to obtain a product with a higher content of TP, monomeric anthocyanins and a stronger antioxidant capacity than HACD at 90°C + MWVD. Combination of HACD at 60°C with MWVD allowed for the shortening of HACD time by 75% as well as for hapering the chemical changes as compared to HACD at 60°C. Even when the combination of HACD at 90°C with MWVD shortened the drying time by 68%, it did not improve the retention of TP, monomeric anthocyanins and antioxidant capacity when compared to HACD at 90°C.

The Influence of Selected Drying Methods on the Physical Properties of Dried Apples cv. Jonagold Grown in Different Locations in Europe

The aim of the study was to determine the influence of four different growing locations of apples cv. ‘Jonagold’ in Europe on the drying kinetics and the physical properties of dried apple slices. The drying methods applied in the study (freeze-drying, convective drying, microwave-vacuum drying and combined drying) significantly affected the drying time, which was the shortest in the case of microwave vacuum drying. The geographical origin of the apples affected the chemical and physical properties of the raw material used for drying, and, consequently, the drying time. Water activity of dried samples was connected with the final dry matter, regardless of the geographical origin of the apples. Freeze-drying resulted in the lightest in colour products (L*), whereas microwave-vacuum dried products had the highest levels of yellow pigments (b*). The highest chroma and browning index values were noted for microwave-vacuum dried samples and were strongly influenced by the drying temperature. The mechanical properties of the apple slices were more dependent on the drying method and temperature of the process than on the geographical origin when the temperature exceeded 83 °C.

Chemical Composition and Antioxidant Properties of Powders Obtained from Different Plum Juice Formulations

Among popular crops, plum (Prunus domestica L.) has received special attention due to its health-promoting properties. The seasonality of this fruit makes it impossible to consume it throughout the year, so new products in a powder form may offer an alternative to fresh consumption and may be used as high-quality natural food ingredients. A 100% plum (cultivar “Valor”) juice was mixed with three different concentrations of maltodextrin or subjected to sugars removal by amberlite-XAD column, and dried using the freeze, spray, and vacuum (40, 60, and 80 °C) drying techniques. The identification and quantification of phenolic acids, flavonols, and anthocyanins in plum powders was performed by LC-MS QTof and UPLC-PDA, respectively. l-ascorbic acid, hydroxymethylfurfural, and antioxidant capacity were measured by the Trolox equivalent antioxidant capacity (TEAC) ABTS and ferric reducing antioxidant potential (FRAP) methods in order to compare the influence of the drying methods on product quality. The results indicated that the profile of polyphenolic compounds in the plum juice powders significantly differed from the whole plum powders. The drying of a sugar free plum extract resulted in higher content of polyphenolic compounds, l-ascorbic acid and antioxidant capacity, but lower content of hydroxymethylfurfural, regardless of drying method applied. Thus, the formulation of plum juice before drying and the drying method should be carefully selected in order to obtain high-quality powders.

Overall Quality of Fruits and Vegetables Products Affected by the Drying Processes with the Assistance of Vacuum-Microwaves

The seasonality of fruits and vegetables makes it impossible to consume and use them throughout the year, thus numerous processing efforts have been made to offer an alternative to their fresh consumption and application. To prolong their availability on the market, drying has received special attention as currently this method is considered one of the most common ways for obtaining food and pharmaceutical products from natural sources. This paper demonstrates the weakness of common drying methods applied for fruits and vegetables and the possible ways to improve the quality using different drying techniques or their combination with an emphasis on the microwave energy. Particular attention has been drawn to the combined drying with the assistance of vacuum-microwaves. The quality of the dried products was ascribed by chemical properties including the content of polyphenols, antioxidant capacity and volatiles as well as physical parameters such as color, shrinkage, porosity and texture. Both these fields of quality classification were considered taking into account sensory attributes and energy aspects in the perspective of possible industrial applications. In conclusion, the most promising way for improving the quality of dried fruit and vegetable products is hybrid drying consisting of osmotic dehydration in concentrated fruit juices followed by heat pump drying and vacuum-microwave finish drying.

Microwave-assisted drying of blueberry (Vaccinium corymbosum L.) fruits: Drying kinetics, polyphenols, anthocyanins, antioxidant capacity, colour and texture

The aim of the study was to evaluate the effect of hot air convective drying (HACD), microwave vacuum drying (MWVD) and their combination (HACD+MWVD) on the drying kinetics, colour, total polyphenols, anthocyanins antioxidant capacity and texture of frozen/thawed blueberries. Drying resulted in reduction of total polyphenols content and antioxidant capacity (69 and 77%, respectively). The highest content of total polyphenols was noted after HACD at 90°C. Lower air temperature and prolonged exposure to oxygen resulted in greater degradation of polyphenols and antioxidant capacity. Drying processes caused a significant decrease (from 70 to 95%) in the content of anthocyanins. The highest content of anthocyanins and the strongest antioxidant capacity was found in blueberries dried using HACD at 90°C+MWVD. Among drying methods, HACD at 90°C+MWVD satisfied significant requirements for dried fruits i.e. short drying time and improved product quality.

Physicochemical properties of whole fruit plum powders obtained using different drying technologies

Physicochemical quality parameters of plum powders obtained by applying conventional drying methods and their combination devised to process plums were evaluated. The effect of freeze-drying (FD), vacuum drying (VD), convective drying (CD), microwave-vacuum drying (MVD) and combination of convective pre-drying and microwave finish-drying (CPD-MVFD) affected physical (bulk density, porosity, colour, solubility) and chemical (polyphenolic compounds determined by UPLC and antioxidant capacity by TEAC ABTS and FRAP methods) properties of plum powders. The MVD at 1.2 W g(-1) and a novel combination for plum powders production - CPD-MVFD at 70 °C/1.2 W g(-1) allowed the best preservation of phenolic compounds and increased the efficiency of production. Results obtained support the use of MVD and its combination for better quality of dried plum products. The study proved that the determination of the browning index and HMF level (formed via Maillard reaction) might be good tool for monitoring the thermal processing of plum powders.

Bioactive Compounds of Blueberries: Post-Harvest Factors Influencing the Nutritional Value of Products

Blueberries, besides having commonly-recognized taste properties, are also a valuable source of health-promoting bioactive compounds. For several decades, blueberries have gained in popularity all over the world, and recent years have seen not only an increase in fresh consumption, but also in the importance of blueberries for the processing industry. Blueberry processing mostly consists of freezing and juicing. Recently, more attention has been drawn to dewatering and drying, which are promising areas for developing novel blueberry products. Processing affects each biologically-active compound in a different way, and it is still unknown what changes those compounds undergo at the molecular level after the application of different processing technologies. This work presents the most recent state of knowledge about the pre-treatment and processing methods applied to blueberries and their influence on the content of biologically-active compounds. The presentation of methods is preceded by a brief overview of the characteristics of the blueberry species, a description of the chemical composition of the fruit and a short note about the main growing areas, production volumes and the management of fruit crops.

Selective ion-sensing with membrane-functionalized electrolyte-gated carbon nanotube field-effect transistors

In this work the ion-selective response of an electrolyte-gated carbon-nanotube field-effect transistor (CNT-FET) towards K(+), Ca(2+) and Cl(-) in the biologically relevant concentration range from 10(-1) M to 10(-6) M is demonstrated. The ion-selective response is achieved by modifying the gate-electrode of an electrolyte-gated CNT-FET with ion-selective membranes, which are selective towards the respective target analyte ions. The selectivity, assured by the ion-selective poly(vinyl chloride) based membrane, allows the successful application of the herein proposed K(+)-selective CNT-FET to detect changes in the K(+) activity in the μM range even in solutions containing different ionic backgrounds. The sensing mechanism relies on a superposition of both an ion-sensitive response of the CNT-network as well as a change of the effective gate potential present at the semiconducting channel due to a selective and ion activity-dependent response of the membrane towards different types of ions. Moreover, the combination of a CNT-FET as a transducing element gated with an ion-selective coated-wire electrode offers the possibility to miniaturize the already well-established conventional ion-selective electrode setup. This approach represents a valuable strategy for the realization of portable, multi-purpose and low-cost biosensing devices.

Identification of plasmid OXA and other β-lactamase genes among carbapenem-resistant isolates of Pseudomonas aeruginosa from the Clinical University Hospital in northeastern Poland

The aim of the study was to evaluate the prevalence of OXA and other β-lactamase genes, antibiotic susceptibility, and the genetic relatedness among clinical isolates of P. aeruginosa resistant to carbapenems. The presence of bla- OXA genes was demonstrated in 48% of isolates belonging to four PFGE profiles. Most of them contained the blaOXA-2 gene (88.3%). Other blaOXA genes (Ps1310 with blaOXA-30 and Ps1309 with blaOXA-10) were found in only two isolates. The tested isolates also contained other β-lactamase genes such as blaVIM-2, blaVIM-4, blaSHV-5, and blaTEM-1. All isolates were susceptible only to colistin (100%).

Human meningitis caused by Streptococcus suis

Streptococcus suis is an important swine pathogen worldwide, which can be transmitted to human beings by direct contact; therefore, S. suis infections occur mainly in people who handle pigs or pork. We present a case of a patient with S. suis meningitis who worked as a butcher in a meat processing plant for 5 years. The 35-year-old man was admitted to the Department of Infectious Diseases in T. Browicz Memorial Central Infectious Disease and Observation Hospital in Bydgoszcz, Poland, with suspected bacterial meningitis. According to his medical history, the patient had been injured during the processing of pork. A microbiological examination of the cerebrospinal fluid and blood revealed S. suis as a single aetiological factor of this infection. The patient was empirically administered cefotaxime (2.0 g at 8-h intervals) and penicillin (9 million U at 8-h intervals). The patient made a complete recovery and his inflammatory markers normalized. Only the hearing deficit of his right ear did not disappear. An otolaryngologist recommended a 4-week steroid therapy. The patient was not examined because he did not report to the clinic. To our knowledge this is the first described case of human meningitis caused by S. suis in Poland.

Indocyanine green angiography in chronic central serous chorioretinopathy

BACKGROUND

Central serous chorioretinopathy (CSC) is a condition that originates from alterations of the choroidal circulation. The aim of this paper was to evaluate the use of indocyanine green angiography (ICGA) in patients with chronic CSC.

MATERIAL/METHODS

The analysis included 17 patients (34 eyes) with chronic CSC in at least 1 eye. The eye examination included: distance and near visual acuity, biomicroscopy, applanation tonometry, fundus examination, colored and red-free fundus photography, evaluation of autofluorescence, optical coherence tomography, and fluorescein and indocyanine green angiography.

RESULTS

In 34 eyes (100%) involved in the ICGA study the results revealed zones of transient increased choroidal vessels permeability. In 18 eyes (52.9%) choroidal changes were accompanied by a focal serous pigment epithelial detachment. In 4 eyes (11.8%) of 3 patients' the ICGA examination confirmed the presence of occult choroidal neovascularization (CNV). In the patient with bilateral diffuse retinal pigment epitheliopathy, CNV was present in 1 eye, in the patient with unilateral chronic CSC it was also present in 1 eye, and in the third patient with bilateral chronic CSC it was detected in both eyes.

CONCLUSIONS

ICGA is a very useful examination that enables ophthalmologists to visualize choroidal changes due to chronic CSC, as well as to diagnose occult CNV in chronic CSC.

[Morganella sp. rods--characteristics, infections, mechanisms of resistance to antibiotics]

The Morganella genus is one member of the tribe Proteae, which also includes the genera Proteus and Providencia. These bacteria are commonly present in the environment. Morganella sp. rods are known to be a causative agent of opportunistic hospital infections, mainly urinary tract, wound and blood infections of severe and high mortality, even in cases of an appropriate antibiotic. These bacteria may produce many virulence factors, for example urease, hemolysins, LPS, adhesins and enzymes hydrolyzing and modifying antibiotics commonly used to treat infections. Understanding the diverse biological properties of these rods may be of importance in the development of effective methods of prevention and control of infections with their participation.  

Generation of induced pluripotent stem cell lines from Friedreich ataxia patients

Friedreich ataxia (FRDA) is an autosomal recessive disorder characterised by neurodegeneration and cardiomyopathy. It is caused by a trinucleotide (GAA) repeat expansion in the first intron of the FXN gene that results in reduced synthesis of FXN mRNA and its protein product, frataxin. We report the generation of induced pluripotent stem (iPS) cell lines derived from skin fibroblasts from two FRDA patients. Each of the patient-derived iPS (FA-iPS) cell lines maintain the GAA repeat expansion and the reduced FXN mRNA expression that are characteristic of the patient. The FA-iPS cells are pluripotent and form teratomas when injected into nude mice. We demonstrate that following in vitro differentiation the FA-iPS cells give rise to the two cell types primarily affected in FRDA, peripheral neurons and cardiomyocytes. The FA-iPS cell lines have the potential to provide valuable models to study the cellular pathology of FRDA and to develop high-throughput drug screening assays. We have previously demonstrated that stable insertion of a functional human BAC containing the intact FXN gene into stem cells results in the expression of frataxin protein in differentiated neurons. As such, iPS cell lines derived from FRDA patients, following correction of the mutated gene, could provide a useful source of immunocompatible cells for transplantation therapy.

Accelerated stem cell attachment to ultrafine grained titanium

Commercial purity titanium with an average grain size in the low sub-micron range was produced by equal channel angular pressing (ECAP). Attachment of human bone marrow-derived mesenchymal stem cells (hMSCs) to the surface of conventional coarse grained and ECAP-modified titanium was studied. It was demonstrated that the attachment and spreading of hMSCs in the initial stages (up to 24h) of culture was enhanced by grain refinement. Surface characterization by a range of techniques showed that the main factor responsible for the observed acceleration of hMSC attachment and spreading on titanium due to grain refinement in the bulk is the attendant changes in surface topography on the nanoscale. These results indicate that, in addition to its superior mechanical properties, ECAP-modified titanium possesses improved biocompatibility, which makes it to a potent candidate for applications in medical implants.

[Antimicrobial sensitive of Morganella morganii]

The aim of this study was the evaluation of the antimicrobial sensitive of Morganella morganii rods isolated from clinical samples. This study included 50 of M. morganii strains isolated in the Clinical Microbiology Department of dr. A. Jurasz University Hospital in 2008-2009. All of strains were sensitive to carbapenems (imipenem, meropenem, ertapenem, doripenem) and piperacillin/tazobactam and most of them to beta-lactam antibiotics, aminoglycosides and fluorochinolons. Resistance to tetracyclines demonstrated 38,0% strains and to doxycycline - 40,0%. One out of 6 strains isolated from urine samples were sensitive to nitrofurantoin. Extended Spectrum Beta-Lactamases were produced by 5 (10,0%) strains.

[Extracellular slime production and adhesion of Morganella morganii strains to polystyrene]

The aim of this study was the evaluation of the ability of extracellular slime production and adhesive properties of M. morganii strains. This study included 50 of M. morganii strains isolated from clinical samples. All of these strains were isolated in the Clinical Microbiology Department of dr. A. Jurasz University Hospital in 2008-2009. Five (10.0%) out of 50. M. morganii strains demonstrated extracellular slime production. Adherence to polystyrene revealed 36 (72.0%) of M. morganii strains in it 6 strains (12.0%) adhered strongly, medium - 12 (24.0%) and weakly - 18 (36.0%).

[Susceptibility to antibiotics of Enterobacter spp. rods isolated from urine]

Enterobacter spp. rods are opportunistic microorganisms which cause of urinary tract infections. The aim of this study was the evaluation of the susceptibility to antimicrobial agents antibiotics of Enterobacter spp. rods isolated from urine. The study was carried 50 of Enterobacter spp strains isolated in the Clinical Microbiology Department of dr. A. Jurasz University Hospital. Antibiotic susceptibility was tested by disk diffusion method. All of strains were susceptible to imipenem and meropenem. There was 87,5% of strains sensitive to doripenem, 79,2% to ertapenem, 54,0% to piperacillin/tazobactam and 50,0% to cephepime. The relatively high percentage (62,0%) of Enterobacter spp. was sensitive to fluoroquinolones. Extended spectrum beta-lactamases were produced by 24 (48,0%) strains.