RIOFH - Repository of Institute of General and Physical Chemistry
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Essential oil versus supercritical fluid extracts of winter savory (Satureja montana L.) - Assessment of the oxidative, microbiological and sensory quality of fresh pork sausages
No full textThe effect of winter savory (Satureja montana L.) essential oil (SEO) and supercritical extracts (SE1; SE2) at concentrations of 0.075 and 0.150 mu L/g on pH, lipid oxidation (TBARS), microbial growth and sensory quality of fresh pork sausages during storage were investigated. SEO, SE1 and SE2 improved oxidative and microbial stability of fresh pork sausages. The addition of SEO and SE1 at concentration of 0.150 mu L/g affected the reduction of total Enterobacteriaeceae count to under 3 log cfu/g. Sausages produced with SE1 and SE2 had a higher scores for odor, flavor and overall acceptance compared to sausages treated with SEO and control sample. Therefore, the results of this paper revealed significant antioxidative and antimicrobial activity of SE1 and SE2, and consequently its high potential of utilization in processing of fresh pork sausages
The Effect of Cantharellus Cibarius Addition on Quality Characteristics of Frankfurter during Refrigerated Storage
No full textThe antioxidant and antimicrobial properties of Cantharellus cibarius decoction and the effect of mushroom addition on the physicochemical and microbiological properties of frankfurters during refrigerated storage were studied. Mushroom addition significantly reduced (p LT 0.05) the formation of total aerobic mesophilic bacteria during storage. Regarding the texture, there was no negative effect in frankfurters with the mushroom added, compared to the control group of sausages. Generally, C. cibarius can be used as a natural ingredient in order to prevent the growth of microorganisms in cooked pork sausages, causing an extension in shelf life during chilled storage
Pt/C catalyst impregnated with tungsten-oxide - Hydrogen oxidation reaction vs. CO tolerance
No full textHydrogen Oxidation Reaction (HOR) is anode reaction in Proton exchange membrane fuel cells (PEMFCs) and it has very fast kinetics. However, the purity of fuel (H-2) is very important and can slow down HOR kinetics, affecting the overall PEMFC performance. The performance of commercial Pt/C catalyst impregnated with WOx, as a catalyst for HOR, was investigated using a set of electrochemical methods (cyclic voltammetry, linear scan voltammetry and rotating disk electrode voltammetry). In order to deepen the understanding how WOx, species can contribute CO tolerance of Pt/C, a particular attention was paid to CO poisoning. In the absence of CO, HOR is under diffusion limitations and HOR kinetics is not affected by WOx species. Appreciable HOR current on the electrodes pre-saturated with COads at potentials above 0.3 V vs. RHE, which is not observed for pure Pt/C, was discussed in details. HOR liming diffusion currents for higher concentrations of W are reached at high anodic potentials. The obtained results were explained by donation of OHads by WOx phase for COads removal in the mid potential region and reduced reactivity of Pt surface sites in the vicinity of the Pt vertical bar WOx, interface. The obtained results can provide guidelines for development of novel CO tolerant PEMFC anode catalysts
From mycelium to spores: A whole circle of biological potency of mosaic puffball
No full textMethanol extracts of mosaic puffball (Handkea utriformis, Bovistella utriformis, Lycoperdon utriforme, Calvatia utriformis - current name is a subject of debate), from three different stages - mycelium (HUMIC), immature (HUI) and mature fruiting bodies (HUM) were characterized and tested for antioxidant, antimicrobial and inhibitory activity on tyrosinase, acetyholinesterase (AChE), butyrylcholinesterase (BuChE) and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA-R). Immature, edible, fruiting bodies were shown to be a good source of antioxidants (11.5 mg/g of extract) and cholesterol-lowering agent, lovastatin (234 mu g/g of extract), and exhibited significant antimicrobial activity. In addition, HUI showed good and selective AChE (4.48 mg/mL) and non-lovastatin related HMG-CoA-R inhibition (1.16 mg/mL), which all together suggests that regular consumption of it may have health benefits. Mature fruiting bodies, inedible due to powdery consistence, have been used in traditional medicine for wound treatment; their extract was relatively rich in free ergosterol (31.65 mg/g of extract), N-acetylglucosamine (24 mg/g of extract), alpha-tocopherol (4 mg/g of extract) and had best overall antioxidant activity, which was in correlation with its highest phenolic content (19.4 mg GAE/mL). It also exhibited significant tyrosinase inhibitory activity (0.22 mg/mL) and thus could be used in medicinal and cosmetic products for wound healing and bleaching. Mycelium, which can be easily grown in laboratory conditions did not have the same properties as, neither immature or mature fruiting bodies, although it showed prominent antimicrobial activity, notably against Pseudomonas aeruginosa (MIC = 0.0625 mg/mL) and could be a source of antimicrobial compounds
Enhancement of antioxidant activity and bioactive compound contents in yellow soybean by plant-extract-based products
No full textPolyphenols present in different plant cell organelles increase the resistance of plants to various types of environmental stresses. We investigated the possibility of increasing the content of bioactive compounds in the seed of yellow soybean variety Laura. The soybean was treated during vegetation with five products based on plant extracts, on the assumption of enrichment of plants with various nutrients. Soybean flour extracts were screened spectrophotometrically for total phenolic content and antioxidant activity. The antioxidant activity was evaluated using three methods. The content of phenolic acids was determined by HPLC, and the raw protein content was estimated by the Kjeldahl method. Depending on the treatment, variations in the quantity of individual phenolic acids with up to 90% higher concentration as compared to the control were observed. Controlled usage of certain plant extracts can increase the concentration of the target group of bioactive compounds in the samples. The synergistic effect of proteins and phenolic compounds on the antioxidant activity of extracts was detected. The results of this study are not only important from the aspect of plant resistance to various types of stress, but also when considering soybean as a functional food
The prediction of lean meat and subcutaneous fat with skin content in pork cuts on the carcass meatness and weight
No full textEarly post-mortem, objective and non-destructive prediction of tissue distribution in the major pork cuts is a challenge for the meat industry. Mathematical models to predict pig carcass composition using total lean meat percentage and carcass weight were evaluated in this study. The data were obtained from 455 cold pig carcasses which were dissected according to the EU reference method; total lean meat percentage and carcass weight ranged from 42.45 to 69.21% and from 23.26 to 55.22 kg, respectively. Developed empirical models gave a reasonable fit to the experimental data and successfully predicted the carcass composition and tissue distribution in primal cuts. The second order polynomial models showed high coefficients of determination for prediction of experimental results (between 0.612 and 0.929), while the artificial neural network (ANN) model, based on the Broyden-Fletcher-Goldfarb-Shanno iterative algorithm, showed better prediction capabilities (overall r(2) was 0.889). The newly developed software, based on ANN model is easy, fast, cheap and with sufficient precision for application in the meat industry
Corn grain brushing for deoxynivalenol reduction
No full textFor the purpose of deoxynivalenol (DON) reduction in corn samples, a laboratory brusher was developed. The brusher had two main parts, motionless screen and fast rotating brush. Corn kernels were placed on the motionless screen of the brusher, and fast rotating round shaped polypropylene bristle brush was put into the motionless screen in order to clean the surface of the kernels. The experiment consisted of 27 brushing trials with variations in process parameters (DON concentration, brushing time, and speed of rotating brush). Brushing of corn that is DON infected resulted in the reduction of DON concentration in all samples. The maximal limit of DON reduction at optimal conditions was 83.6%. Thus, the presented process can be considered as highly efficient. The proposed technology did not cause any changes in the physical appearance of kernel, nor were damages observed on kernel surface during the brushing process. Also, there were no whole grain losses detected in any of the process parameter combination
Immobilization of Chaga extract in alginate beads for modified release: simplicity meets efficiency
No full textChaga (Inonotus obliquus) is a parasitic fungus, which has been used in traditional medicine in Russia and other northern European countries in the treatment of cancer, gastrointestinal andliver diseases. It has been a subject of intensive researchrecently, confirming many of its health-beneficial effects. In order to obtain a product that would allow modified and prolonged release of the Chaga's active metabolites, hot water Chaga extract was immobilized using calcium - alginate. The extract, which was predominantly composed of carbohydrates (57 %), also contained a relatively high amount of antioxidants/phenolic compounds (130 mg gallic acid equivalents per g of dry extract) and exhibited pronounced radical scavenging activity. It showed significant antibacterial activity as well, inhibiting growth of tested bacterial strains at concentrations of 1.25-20 mg/mL. Entrapment efficiency was about 80 %, and the extract-alginate system showed pH-dependant extract release; there was negligible release at pH 1.75 (gastric pH), and the release gradually increased with the increase in pH, reaching similar to 43 % of immobilized extract at pH 8.5 after 90 min. Such a product could be used as a dietary supplement, adjuvant in therapy of gastrointestinal diseases or as a food additive
3D Digital Image Correlation Analysis of the Shrinkage Strain in Four Dual Cure Composite Cements
No full textThe introduction of resin-based cements and an adhesive-bonding system in daily dental practice has given the opportunity to increase the retention of previously conventional cemented restorations and the optimal results in esthetic. This experimental study employed the 3D Digital Image Correlation Method (3D-DIC) for detecting shrinkage strain in four dual cured composite cements. The aim was to visualize measure, analyze, and compare strain fields in four resin-based cements using the 3D-DIC method. A total of 72 samples were divided into 4 groups considering variations in sample types, diameter, and thickness. Four types of composite cements: RelyX U200 (3 M ESPE, St. Paul, MN, USA), MaxCem Elite (Kerr, Orange, CA, USA), Multilink Automix (Ivoclar Vivadent, Schaan, Liechtenstein), and SeT PP (SDI, Australia) were used. Each type had diameters of 3 mm, 4 mm, and 5 mm, respectively, combined with two different values of thickness: 1 mm and 2 mm. Thickness had an important role on strain detected in all tested materials showing higher strain in samples with 2 mm thickness compared to 1 mm samples. Shrinkage strain values were the highest in Set PP samples indicated the possibility of undesirable de-bonding