Without being aware of its chemical makeup, many ancient societies have used Steppe peony in their traditional medicine. Given that modern phytopreparation intended for use on human skin requires, ...above all, knowledge of its chemical composition, the goal of this study was to make a screening of the composition of aqueous and methanolic extracts of the petals of
L. and to examine them for various skin-beneficial properties. The extracts were prepared by maceration, ultrasound-assisted, and microwave-assisted extraction procedures. The chemical profiling was conducted by the use of UHPLC-LTQ-OrbiTrap MS and UHPLC/MS, and spectrophotometric methods for the determination of total polyphenol and total flavonoid contents. The biological activities entailed antioxidant ABTS, DPPH, CUPRAC (Cupric Ion Reducing Antioxidant Capacity), and FRAP (Ferric Reducing Antioxidant Power) assays, antimicrobial (antibacterial and antifungal) and antibiofilm activities, cytotoxicity, wound healing potential, as well as the adhesion and invasion of
. The results showed that the petals are rich in phenolic acids and flavonoids, which are commonly associated with numerous biological activities. The aqueous extracts were more efficient in the majority of the bioactivity assays then the methanolic ones, whereas the optimal extraction method varied between the assays. This study is the first step towards the safe use of the aqueous extracts of
petals for therapeutic skin treatments.
Effect of pre-harvest calcium chloride (CaCl2) treatment on fruit quality attributes of three apple cultivars ('Golden Delicious Reinders®', 'Granny Smith' and 'Red Chief') at harvest and after two ...and four months of cold storage during two consecutive years was studied. Trees were sprayed four times starting from the beginning of June at 20-day intervals. After harvest, fruits were stored in a regular atmosphere (RA) for further analysis. Measurements included fruit weight, weight loss, firmness, total soluble solids (TSS), titrable acidity (TA), total sugars (TS), TS/TA, total phenolic content (TPC) and antioxidant activity (AA). CaCl2 had a positive impact on fruit firmness of all cultivars in both years. Higher values of TSS and TS of 'Golden Delicious Reinders®' were determined in CaCl2 treatment in both years. TSS, TS and TS/TA were increased by prolonging storage in 'Red Chief' in CaCl2 treatment and control, in both years. TSS and TS proved similarly stable in 'Granny Smith' during storage in CaCl2 treatment and control in the second year of examination, but a decrease of TA and TS/TA has been detected in both years of storage. The AA of cultivars 'Golden Delicious Reinders®' and 'Red Chief' was stronger affected by the storage compared to CaCl2 treatment. Through a comprehensive analysis of apple cultivars it can be concluded that pre-harvest application of CaCl2 in cultivars 'Golden Delicious Reinders®' and 'Red Chief' can be used to improve fruit quality during storage.
Even though peonies are highly valued as ornamental, medicinal, and edible species and are also considered to be long-lived and relatively disease and pest resistant, they are becoming rare or ...endangered in their natural habitats. This could be primarily associated with climate change and unsustainable wild collecting practices. So far, in situ conservation efforts have received little attention. In addition, very little is known about the cultivation of herbaceous peonies, particularly their propagation from seeds. What is known is that their seeds possess double dormancy, often accompanied by a low germination rate, which, together, make the cultivation of herbaceous peonies more difficult. Based on a comprehensive analysis of relevant literature, this paper summarizes, analyzes, and discusses all available studies on the seed traits of herbaceous peonies associated with the effect of seed harvest time on dormancy and seed germination, with a strong focus on dormancy breaking procedures. Improving our understanding of dormancy release modalities (impacts of temperature, moisture, light, hormones, various pre-treatments, etc.) will aid the establishment and management of in situ and ex situ collections of valuable species of herbaceous peonies and enable further studies for their successful propagation, breeding, and cultivation.
In this study, the petals collected from peony hybrid Paeonia lactiflora "Bowl of Beauty" and Calendula officinalis L. were extracted using an ethanol-water mixture assisted with microwave and ...ultrasonic treatment. The isolation of Calendula officinalis L. essential oil was done by hydrodistillation as well. The total phenolic and flavonoids content in the extracts and oil were determined and their antioxidant activity was evaluated. The highest total phenolic content was found for the extracts of hybrid P. lactiflora and C. officinalis L. obtained by ultrasound extraction (83.16 and 114.47 mg GA/g, respectively), while the flavonoid content obtained by microwave-assisted extraction was relatively high (123.48 and 65.29 mg QE/g, respectively). The highest antioxidant activity was obtained in DPPH• and ABTS•+ assay for the microwave-assisted extraction of hybrid P. lactiflora (79% and 83%) and ultrasound-assisted extraction of C. officinalis L. (45% and 49%), respectively. To improve antioxidant activity of both types of examined analytes (extracts and essential oil), the pectin biopolymer film (as a carrier) was prepared in the process of enzymatically assisted catalysis. Optical microscopy and FTIR spectroscopy were used for the characterization of obtained materials. The films, with essential oil of C. officinalis L. and gallic acid, showed significantly increased percentage inhibition in DPPH• and ABTS•+ test (91% and 95%, respectively) after 10 minutes. The results, also, showed that all formulations of pectin biopolymer film, modified with gallic acid, can be successfully applied as a carrier for both types of ingredients.
During a five-year field trial established with Satureja montana L. under polypropylene woven fabric (PPWF) on clay-textured soil in dry farming conditions in South Banat, Serbia, the influence of a ...single basal application of compost and mineral fertilizers at different planting densities (3.6 and 5 plants m−2) on the yield was investigated. Single-dose fertilization positively influenced the yields of S. montana in both applied fertilization models. In the third production year, the dry herb yield achieved by applying organic fertilizers in dense cultivation (1016 g m−1) was comparable with that obtained in the mineral plot (961 g m−1). Furthermore, the plants were optimally supplied with N, P, and K macronutrients, with equal amounts removed by yield, in both tested fertilization plots. The use of PPWF proved beneficial to cultivated plants in terms of water-use efficiency and weed suppression. However, severe yield loss was observed in the fourth and fifth production years as a result of the extreme rainfall conditions; the excess moisture retained by PPWF applied to heavy clay soil favored the development of soil-borne pathogens. Other mulch materials should be further investigated for the production of S. montana on heavy clay soil.
Effects of 3-D surface roughness on the propagation constant of transverse electromagnetic transmission lines are calculated using finite-element method software by solving for the fields inside ...conductors. The modeling is validated by comparison with available literature results for the special case of 2-D surface roughness and by simulations using the finite-integration technique. Results for cubical, semiellipsoidal, and pyramidal indentations, as well as rectangular, semicircular, and triangular grooves in conductor surfaces are presented. A developed surface roughness model is applied to rectangular mu-coaxial lines. It is shown that roughness contributes up to 9.2% to their overall loss for frequencies below 40 GHz
In order to preserve the quality of apple fruit, it is crucial to choose the most suitable storage technology. Nevertheless, it is also important to maintain the quality of apples during the shelf ...life period. In this study, changes in various biochemical quality parameters of ‘Golden Delicious’ and ‘Idared’ apples during a prolonged shelf life period, after conventional normal atmosphere (NA) and ultra-low oxygen (ULO) storage, were investigated. After the harvest, the fruit of examined cultivars were stored in two atmospheres for six months. Weight loss, changes in content of sugars, organic acids, total phenols, total flavonoids, pectic fractions, and antioxidant capacity were monitored. Samples were evaluated immediately after removal from the cold chambers and after 10 and 20 days of shelf life at 20 °C. ‘Golden Delicious’ apples stored in ULO exhibited better qualitative characteristics during 20 days of shelf life compared with apples of the same cultivar stored in NA. However, evaluated traits in ‘Idared’ apples from NA chambers were of higher quality in comparison with ‘Idared’ apples stored in the ULO atmosphere.
Five plum hybrids (38/62/70, IV/63/81, 32/21/87, 34/41/87 and 22/17/87) and newly released cultivar ‘Nada’, obtained by planned hybridisation and singled out within breeding programme at Fruit ...Research Institute, Čačak, were assessed for the main physical (fruit and stone weight and flesh percentage), chemical (soluble solids content, total and inverted sugars content, sucrose content, total acids content, pH value of fruit juice, ratio of soluble solids and total acids content and ratio of total sugars and total acids content) and sensorial (attractiveness, taste, aroma and consistency) traits compared with the standard cultivar ʻČačanska Lepoticaʼ. Results showed that the studied plum genotypes differed significantly in all of the assessed traits. Regarding the physical features, the best results were shown by hybrid 38/62/70, which had the highest fruit weight (56.92 g) and flesh percentage (96.91%), as well as by the new cultivar ‘Nada’, for which a larger fruit was observed in comparison to the standard (45.54 g and 42.24 g, respectively). Also, ‘Nada’ had better sensorial properties such as attractiveness, taste, aroma and consistency in relation to the other promising hybrids and the standard cultivar. From the aspect of all the studied sensorial characteristics, in addition to ‘Nada’, only hybrid 38/62/70 was aligned with the standard cultivar. Out of the studied genotypes, late ripening hybrid 22/17/87 had the best values of parameters of fruit chemical composition such as the soluble solids content (17.01%), total and inverted sugars contents (12.31% and 8.96%, respectively). The highest sucrose content (3.39%), pH value of fruit juice (3.51), as well as the highest ratio between soluble solids and total acids content (43.72) and ratio between total sugars and total acids content (32.58) were found in cultivar ‘Nada’. The highest total acids content (1.42%) was recorded in hybrid 32/21/87. Compared to ʻČačanska Lepoticaʼ, the same or better results in terms of the fruit chemical composition were determined in cultivar ‘Nada’ and hybrids 34/41/87 and 22/17/87. The study revealed existence of significant correlations between individual studied parameters of the fruit physical, chemical and sensorial properties.
This paper presents a novel single-channel IGBT driver circuit together with a procedure for testing and verification. It is based on a specialized integrated circuit with complete range of ...protective functions. Experiments are performed to test and verify its behaviour. Experimental results are presented in the form of oscilloscope recordings. It is concluded that the new driver circuit is compatible with modern IGBT transistors and power converter demands and that it can be applied in new designs. It is a part of new 20kW industrial-grade boost converter.
This paper presents the influence of thermal aspects in design process of an industrial single-phase inverter, choice of its topology and components. Stringent design inputs like very high overload ...level, demand for natural cooling and very wide input voltage range have made conventional circuit topology inappropriate therefore asking for alternative solution. Different power losses calculations in semiconductors are performed and compared, outlining the guidelines how to choose the final topology. Some recommendations in power magnetic components design are given. Based on the final project, a 20kVA single-phase inverter for thermal power plant supervisory and control system is designed and commissioned.
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