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Industrial hemp nutraceutical processing and technology
No full textIndustrial hemp (Cannabis sativa L.) is highlighted as an emerging source of different valuable bioactive compounds (fibers, proteins, oil, cannabinoids, polyphenols, etc.). There has been a great interest recently in application of various extraction techniques for the recovery of bioactives from different parts of hemp, as well as from by-products and side streams generated from the conventional hemp processing. The basic principles of traditional and novel extraction techniques (ultrasound-assisted, microwave-assisted, supercritical fluid, pressurized-liquid extraction, etc.), as well as different encapsulation techniques, are applied for further processing of the extracts. Special emphasis has been given on advantages and limitations, challenges and opportunities in processing of hemp bioactives. Finally, this chapter summarizes the recent findings on the use of these technologies to recover and encapsulate various hemp compounds in order to obtain products with high bioactive potential for further industrial use
Molecular dysprosium complexes for white-light and near-infrared emission controlled by the coordination environment
No full textA series of single-molecule dysprosium (Dy3+) complexes consisting of beta-diketonate ligands, L-1 = 4,4,4-trifluoro-1-phenyl-1,3-butadionate and L-2 = 4,4,4-trifluoro-1-(4-chlorophenyl)-1,3-butadionate, as water-containing complexes, and the auxiliary triphenylphosphine oxide (tppo) ligand as water-free complexes were investigated as potential white-light emitters. The coordination environment and choice of the ligands play an important role in the behavior of the yellow/blue emission of the Dy3+ complexes (Y: F-4(9/2) -> H-6(13/2) - yellow, and B: F-4(9/2) -> H-6(15/2) and ligand phosphorescence - blue) based on the sensitization efficiency of the Dy3+ ion by the ligands. By introducing the auxiliary tppo ligand in the complex, the relative intensity of the Dy3+ emission increases due to a more efficient sensitization of the Dy3+ ion. The CIE (Commission International d'Eclairage) coordination at room temperature for water-containing, DyL1H2O (0.340, 0.333), and DyL2H2O (0.270, 0.249), and for water-free complexes, DyL(1)tppo (0.364,0.391) and DyL(2)tppo (0.316, 0.331), are close to the coordinates of 'ideal' white light (0.333, 0.333). The CCT (Correlated Color Temperature) values at room temperature for DyL1H2O (5129 K), DyL2H2O (18,173 K), and DyL(2)tppo (6319 K) correspond to 'cold-white-light' emitters, while the DyL(1)tppo (4537 K) matches a 'warm-white-light' emitter. Beside emitting in the visible (Vis) region, the Dy3+ complexes also show emission in the near-infrared (NIR) part of spectrum, which has been studied in detail
Encapsulation of bioactive compounds extracted from Cucurbita moschata pumpkin waste: the multi-objective optimisation study
No full textAim Artificial neural network (ANN) development to find optimal carriers (pea protein-P, maltodextrin-M, and inulin-I) mixture for encapsulation of pumpkin waste bioactive (beta-carotene and phenolics). Methods Freeze-drying encapsulation and encapsulates characterisation in terms of bioactive contents and encapsulation efficiencies, water activity, hygroscopicity, densities, flowability, cohesiveness, particle size (laser diffraction), solubility, colour (CIELab), morphological (SEM), stability and release properties. Results Optimal encapsulates, OE-T (with highest total bioactive contents; P, M, and I of 53.9, 46.1, and 0%w/w) and OE-EE (with highest bioactive encapsulation efficiencies; P, M, and I of 45.5, 32.0, and 22.5%w/w) had particle diameters of 94.561 +/- 1.341 mu m and 90.206 +/- 0.571 mu m, the span of 1.777 +/- 0.094 and 1.588 +/- 0.089, highest release at pH 7.4 of phenolics of 71.03%w/w after 72 h and 66.22%w/w after 48 h, and beta-carotene of 43.67%w/w after 8 h and 48.62%w/w after 6 h, respectively. Conclusion ANN model for prediction of encapsulates' preparation, showed good anticipation properties (with gained determination coefficients of 1.000)
Thermal and dielectric properties of low-density polyethylene/NaA zeolite composites
No full textThe effect of the weight fraction of NaA zeolite on thermal properties (specific heat capacity, thermal diffusivity, thermal conductivity) and dielectric properties (electrical conductivity, real and imaginary electric permittivity) of composites based on low-density polyethylene (LDPE) and NaA zeolite is examined. Composite samples containing from 5 to 30 wt% zeolite are prepared using the compression molding technique. The degree of dispersion and the weight fraction of filler in the LDPE/NaA zeolite composites are determined using X-ray diffraction. A linear decrease in the values of the specific heat capacity with an increase in the weight fraction of zeolite is observed using differential scanning calorimetry. The laser flash method is used to determine the thermal diffusivity of the composites. An increase in effective thermal diffusivity and abrupt increase in the range from 15 to 20 wt% of zeolite are established. It is demonstrated that effective thermal conductivity increases with an increase in the weight fraction of zeolite, and an abrupt increase in the range from 15 to 20 wt% is observed. Dielectric spectroscopy measurements are performed to determine the real and imaginary parts of permittivity. An increase of real and imaginary parts of permittivity of LDPE/NaA zeolite composites, with increasing weight fraction of zeolite, is established. Two relaxation peaks of the imaginary parts of permittivity of LDPE/NaA zeolite composites are detected. An increase of electrical conductivity with increasing weight fraction of zeolite and abrupt increase in the range 15 to 20 wt% are noticed
Novel polyurethane network/organoclay nanocomposites: Microstructure and physicochemical properties
No full textA series of novel polyurethane network/organoclay nanocomposites (PUN-NCs) with different soft segment contents (30-60 wt%) was prepared by in situ polymerization in solution and characterized. PU network (PUN) was made from poly(dimethylsiloxane)-based macrodiol as the soft segment and 4,4'-methyl-enediphenyldiisocyanate and hyperbranched polyester of the third pseudo generation as the hard segment. Nanocomposites were obtained by dispersion of organically modified montmorillonite (Cloisite 30B) nanofiller (0.5 wt%). The influence of the soft segment content on the functional properties of PUN-NCs was studied by Fourier transform infrared (FTIR), small-angle and near wide-angle X-ray scattering (SWAXS), thermogravimetric analysis (TGA), dynamic mechanical thermal analyses (DMTA), differential scanning calorimetry (DSC), nanoindentation, atomic force microscopy (AFM), scanning electron microscopy (SEM), and swelling behavior, water absorption and contact angle measurements. The biodegradation process was evaluated using mixed cultures of microorganisms that originated from soil. Mechanically strong PUN-NC materials in the form of films were obtained, pointing to good dispersion and the existence of exfoliated morphology of Cloisite 30B within the PUN matrix, and the nanocomposites with the abovementioned characteristics were obtained as a function of the soft segment content. The decrease of the soft segment content induced a higher degree of phase separated microstructure, increase of Young's modulus, hardness, plasticity, storage modulus, glass transition temperature, surface free energy and swelling ability in tetrahydrofuran, but at the same time, it is responsible for the decrease of crosslinking density and hydrophobicity of PUN-NCs. By choosing adequate soft segment content, the prepared materials can potentially be designed for coating applications, such as top coating materials in environmental conditions
Microencapsulation of juniper berry essential oil (Juniperus communis L.) by spray drying: microcapsule characterization and release kinetics of the oil
No full textYYYMicroencapsulation of juniper berry essential oil (JBEO) has been used for protection of essential oil volatiles, giving the possibility of their implementation as a food flavouring agent and preservative. The objective of this study was to encapsulate JBEO by spray drying and to evaluate the influence of different wall materials [gum arabic (GA), maltodextrin (MD), sodium alginate (ALG) and whey protein concentrate (WPC)] on microcapsule properties. Oil retention efficiency, encapsulation efficiency, moisture content, hygroscopicity, dissolution time, solubility, density properties, flowability, porosity, particle size, thermal behaviour and release properties were analysed. Best results were obtained when JBEO was encapsulated using GA/MD (1:1) as a carrier producing microcapsule with the highest encapsulation efficiency (70.07%) and the best results in density properties, porosity, dissolution time and thermal properties. GA as a carrier formed the microcapsules with the highest oil retention efficiency (84.67%), but due to the high surface oil content had reduced encapsulation efficiency. WPC may be preferable for moisture and hygroscopicity decreasing. The GA/MD formulation had achieved the complete and prolonged release of the JBEO from microcapsules in oily food system. The release profiles were fitted with different mathematical models
Chemical Fruit Profiles of Different Raspberry Cultivars Grown in Specific Norwegian Agroclimatic Conditions
No full textRaspberries are considered valuable fruits due to their high levels of nutrients and phytochemicals, which have many beneficial effects on humans. As many external factors affect the composition of these fruits (the type of cultivation, soil characteristics, ripeness, storage time and post-harvest technologies, cultivar/genotype, and climatic conditions), the goal of this study was to analyze different raspberry cultivars grown in Norway. Considering that Norway is a country with specific climatic conditions, as well as has a limited period of fruit vegetation, another important goal of this study was also to compare raspberries from different Norwegian areas, as well as different grown cultivars. Modern analytical techniques, such as high-performance anion-exchange liquid chromatography with pulsed amperometric detection (HPEAC-PAD), ultra-high-performance liquid chromatography with diode array detector coupled to triple quadrupole mass spectrometry (UHPLC-DAD MS/MS), and inductively coupled plasma-optical emission spectrometry (ICP-OES), provided a detailed examination of the raspberry extract samples. Based on their high levels of minerals (especially N, P, and K), organic acids (predominantly citric and malic acids), sugars (glucose, fructose, sucrose, and galactose), and polyphenols (ellagic acid, syringic acid, quercetin, and rutin), Norwegian raspberries could be considered fruits with increased health-beneficial compounds. The chemical composition of the studied cultivars depended on the locality of growth
Nanocomposites made from thermoplastic linear poly(urethane-siloxane) and organoclay: Composition impact on the properties
No full textThermoplastic poly(urethane-siloxane)/organoclay nanocomposites (TPU NCs) with different hard segment content (20-55 wt. %) were prepared by in situ polymerization in the presence of organically modified montmorillonite as a nanofiller (Cloisite 30B; 1 wt. %). Hydroxyl-terminated ethoxypropyl-poly(dimethylsiloxane) was used as soft segment, while 4,4'-methylenediphenyl diisocyanate and 1,4-butanediol were the hard segment components. The study of the influence of the hard segment content on the functional properties of TPU NCs was performed by Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), dynamic mechanical thermal analyses (DMTA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), water contact angle and water absorption tests. The results revealed that TPU NCs with the increasing hard segment content exhibit higher values of degree of microphase separation, melting temperature of the hard segments, degree of crystallinity, storage modulus (except for TPU NC-55), but lower thermal stability and hydrophobicity. TPU NC films were hydrophobic and their free surface energy was in the range from 17.7 to 24.9 mJ m(-2). This work highlights how the composition of TPU NCs would affect their functional properties and provide an additional composition intended for designing advanced TPU NC materials for special biomedical applications
Model for Determining Noise Level Depending on Traffic Volume at Intersections
No full textThe negative external effects caused by traffic growth have been recognized as the main factors that degrade city quality of life. Therefore, research around the world is being conducted to understand the impact of traffic better and find adequate measures to reduce the negative impact of traffic growth. The central part of this research consists of mathematical models for simulating the negative consequences of congestion and noise pollution. Four non-linear models for determining noise levels as a function of traffic flow parameters (intensity and structure) in the urban environment were developed. The non-linear models, including two artificial neural networks and two random forest models, were developed according to the experimental measurements in Novi Sad, Serbia, in 2019. These non-linear models showed high anticipation accuracy of the equivalent continuous sound level (Laeq), with R-2 values of 0.697, 0.703, 0.959 and 0.882, respectively. According to the developed ANN models, global sensitivity analysis was performed, according to which the number of buses at crossings was the most positively signed influential parameter in Laeq evaluation, while the lowest Laeq value was reached during nighttime. The locations occupied by frequent traffic such as Futoska and Temerinska positively influenced the Laeq value
