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关键词： Beef  

摘要： This study explored the impact of high-intensity ultrasound (US) (HIU;40 kHz, 11 W/cm(2)) on physicochemical characteristics and shelf life of Semitendinosus beef muscle during storage for 0, 3, 6, and 9 d at 4 degrees C. HIU decreased the pH and the global difference of color along with the storage (from 5.99 to 1.43 Delta Epsilon) in comparison with not sonicated beef. The drip loss of beef decreased with US and with storage, but it was similar to the control at the end of 9 d of storage. No difference in water-holding capacity and SF of sonicated beef was observed compared to the controls. Counts of mesophilic, psychrophilic, Staphylococcus spp., and coliform bacteria decreased with HIU application. HIU has proven to be a technology that could be efficiently used to increase the shelf life of beef retaining its technological quality. Practical applications In meat processing, sonication can serve as an alternative processing technique to the traditional methods of meat preservation and is considered a green, versatile, and emerging technology. Ultrasonication was remarkably effective for inactivation of beef microbiota showing a growing effect with storage time. US has minimal effects on physicochemical properties of fresh and stored beef. Hence, these findings offer an opportunity for the meat industry to increase the shelf life of beef retaining its technological quality.

关键词： Alfalfa polysaccharides   Drying methods   Physicochemical characterization   Biological activities  

摘要： Alfalfa (Medicago sativa L.) polysaccharides (MSPs) were subjected to three drying methods, namely, hot-air drying (HD), freeze drying (FD), and vacuum drying (VD). Three corresponding polysaccharides were obtained and named HD-MSPs, FD-MSPs, and VD-MSPs. The physicochemical characteristics and activities of the three MSPs were compared. The results showed that the three MSPs all consisted of five monosaccharides: glucuronic acid, rhamnose, glucose, galactose, and xylose. However, the glucuronic acid contents of HD-MSPs (7.90 %) and VD-MSPs (9.94 %) were lower than that of FD-MSPs (11.65 %). HD-MSPs and VD-MSPs had higher molecular weights than that of FD-MSPs. HD-MSPs possessed higher inhibition activities against ?-amylase and ?-glucosidase than VD-MSPs and FD-MSPs, which might be due to their relatively higher viscosities and molecular weights. The scavenging activities of FD-MSPs for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and 2,2-azino-bis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) radicals were the highest among those of the three MSPs, which might be related to their lower molecular weight and higher content of uronic acid. These results suggested that MSPs obtained by different drying methods possessed different specific characteristics and had the potential to be used for different purposes, where HD-MSPs and FD-MSPs had the potential to be used as a hypoglycemic agent and an antioxidant, respectively.

关键词： set yogurt   passion fruit juice   fortification   fermentation kinetics   antioxidation activity  

摘要： With the purpose of developing an alternative set yogurt with high consumer acceptability, passion fruit juice, at levels that varied from 0 to 10%, was incorporated into set yogurt, and the effects on the fermentation kinetics, physicochemical properties, and functionality of set yogurt were evaluated. The results showed that the addition of passion fruit juice was simultaneously propitious for milk acidification in earlier fermentation stages and reduced the fermentation rate at later stages of fermentation. The phenolic compounds and pectin in passion fruit juice interacted with caseins to form soluble complexes, enhancing the gel strength of set yogurts by 7.5%. The aroma and flavor of the set yogurt was improved as well. However, with the addition of 10% passion fruit juice, the gel structure was destroyed, and the quality of the set yogurt was very degraded. More importantly, the addition of passion fruit juice increased the polyphenol content and significantly enhanced the antioxidant activity of the set yogurt. This investigation demonstrated the feasibility of fabricating passion fruit juice-enriched set yogurt and its superior quality compared with the corresponding normal product.

关键词： Ultrasonic frequency   Pectin modification   Structure   Rheology   Antioxidant activity   Bile acid-binding capacity  

摘要： Ultrasonic irradiation for modified pectin preparation has become a research hotspot, but the influence of ultrasonic frequency is rarely studied. Therefore, in this study, mono frequency (MFU) and simultaneous dual frequency (SDFU) ultrasounds were used to modify citrus pectin (CP), and the effects of different ultrasonic frequency modes on the physicochemical, structural, functional, and biological properties of CP were comparatively investigated. The results showed that ultrasonic irradiation at 40 kHz in the MFU mode led to a larger increment in the galactumnic acid content of CP, but greater reductions in its intrinsic viscosity, molecular weight, and degree of methoxylation than in the SDFU modes. Ultrasonic frequency had no significant influence on the main CP chain, but rather on its neutral sugar side chains. The scanning electron microscopy (SEM) results suggested that CP treated by ultrasound at 40 kHz in the MFU mode exhibited fewer aggregates or looser networks than other ultrasonic treatments. Compared with the original CP, ultrasound treatment at different frequency modes effectively enhanced the thermal stability of CP, but remarkably lowered its shear thinning fluid behavior and liquid-like property. Moreover, among ultrasonically treated CPs, the CP obtained through ultrasound at 40 kHz in MFU mode exhibited the best antioxidant activity and bile acid-binding capacity in vitro.

关键词： Supercritical fluid   Cocrystallization   Particle engineering   CO2   Posaconazole   Design of experiment  

摘要： Posaconazole (PSZ) is a BCS (biopharmaceutical classification system) Class II anti-fungal drug used to treat infections in immunocompromised patients. The work presented herein describes the generation of cocrystals of PSZ with 4-aminobenzoic acid (4AMB) using supercritical CO2 as an antisolvent in GAS (Gas Antisolvent) with acetonitrile, and as a solvent in CSS (Cocrystallization with Supercritical Solvent) methods. Cocrystals of PSZ-4AMB were obtained in a 2:3 stoichiometric ratio for the first time by GAS and CSS methods, with GAS producing higher-purity samples compared to CSS method. The work presented herein investigates the influence of critical processing variables using CO2 solvent and antisolvent crystallization methods with respect to the formation of cocrystals of PSZ-4AMB. A Design of Experiments (DoE) approach was performed to assess the outcome of PSZ-4AMB formation, impacted by processing variables such as pressure, temperature, and stirring rate using GAS and CSS methods. The resulting cocrystalline phase was identified using differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD). The particle morphologies and size distributions were determined using scanning electron microscopy and automated static imaging, respectively.

关键词： Emulsifying index   Particle size   Rheology   Thermal analysis   FTIR  

摘要： The present research investigated the effect of microfluidization treatment (103, 138, 172, and 207 MPa) on pH, refractive index (RI), color measurements, rheology, particle size, emulsifying properties, and thermal denaturation of egg yolk. Color parameters were significantly (p < 0.05) effected by microfluidization treatment. Rheological measurements showed the conversion of newtonian nature to the shear-thinning nature of egg yolk upon microfluidization treatment. Further, yield stress (tau(0)), consistency constant (K), and flow behaviour index (n) were affected by microfluidization. Microfluidization caused a reduction in particle size of yolk with an increase in pressure up to 172 MPa and particle size increased at 207 MPa. Emulsifying activity index (EAI) increased from 30.49 m(2)/g (control) to 32.41 m(2)/g (MEY2) but decreased as microfluidization pressure was increased. Emulsifying stability index (ESI) increased at 103 MPa but decreased as microfluidization pressure increased further. Thermal analysis revealed increase in denaturation temperature as microfluidization pressure increased.

关键词： Diluted alkali-soluble pectin   Dissociation   Gelation   Ion binding   Self-assembling   Surface electrical charge  

摘要： Cross-linking and gelation are important abilities affecting pectin functionality. Pectin concentration, pH and the composition of the dispersing medium play a crucial role in gel formation. The self-assembly of pectin in solution occurs simultaneously with changes in its physicochemical properties. However, this process has not been described in detail to date. Therefore, the effect of pectin concentration on such properties as its surface electrical charge (Q), hydrogen ions binding (beta(H+)) and total counterions binding (beta(tota)(l)) during intermolecular interactions in different media was studied. Low-methoxyl diluted alkali-soluble pectin (DASP) extracted from pear fruits by using sodium carbonate was examined. Investigations were performed on a wide range of its content (1.84.10(-4)-1.84.100% w/v) in water and salt (NaCl and CaCl2) solutions with the ionic strength of 30 mM at 20 degrees C. Back Dynamic Light Scattering, Laser Doppler Electrophoresis, potentiometry and Atomic Force Microscopy methods were used. The DASP dissociation constant was calculated and used for determination of other physicochemical parameters. The relationship between changes in the physical and physicochemical properties of DASP during gelation was shown. An increase in the relative mean hydrodynamic diameter with DASP concentration was connected with the self-assembling (CaCl2) and cross-linking (water, NaCl) processes leading to gel formation. Simultaneously, the Q value decreased, beta(H+), beta(total) and the contribution of beta(H)(+) to beta(total) increased up to the obtained constant values at the gel state. Thus, the physicochemical properties of pectin may be indicators of the particular stages of macromolecules interactions occurring during gelation.

关键词： anthocyanins   3-deoxyanthocyanins   auronidins   color of plants evolution  

摘要： Anthocyanins are the basis of the color of angiosperms, 3-deoxyanthocyanins and sphagnorubin play the same role in mosses and ferns, and auronidins are responsible for the color in liverworts. In this study, the color system of cyanidin-3-O-glucoside (kuromanin) as a representative compound of simpler anthocyanins was fully characterized by stopped flow. This type of anthocyanin cannot confer significant color to plants without intra- or intermolecular interactions, complexation with metals or supramolecular structures as in Commelina communis. The anthocyanin's color system was compared with those of 3-deoxyanthocyanins and riccionidin A, the aglycone of auronidins. The three systems follow the same sequence of chemical reactions, but the respective thermodynamics and kinetics are dramatically different.

关键词： Fermentation   Incubation period   Manganese sulfate   Set yogurt   Vitamin B-12  

摘要： In this study, the effect of MnSO4 center dot H2O (Mn2+) and vitamin B-12 (VitB) on the physicochemical, textural, sensory properties, and bacterial growth of set yogurt were evaluated. A commercial culture containing Lactobacillus bulgaricus delbrueckii and Streptococcus thermophilus and the probiotic bacteria Lactobacillus acidophilus LA5 were used for yogurt production. Moreover, individual and combination treatments of Mn2+ at concentration of 0.006, 0.03, and 0.3 w/w and VitB 0.05, 0.1, and 0.5 w/w were used in the product. Changes in bacterial count of yogurt culture, probiotic bacteria, pH, amount of lactic acid production, hardness, syneresis, color, and sensory properties were examined duration incubation until a pH level of 4.6 at 37 degrees C. Results showed that the addition of Mn2+ and VitB had a significant beneficial effect on the incubation period time. The most significant decreases in incubation period were obtained at 0.006 Mn2+ + 0.5 VitB, 0.03 Mn2+, and 0.5 VitB % which were reduced the incubation time from 300 min to 165, 210, and 225 min, respectively. Combined treatments of Mn2+ and VitB were able to increase the growth of Lactobacillus bulgaricus delbrueckii by 23.6% compared to the control. However, the fermentation process became significantly slower than the control sample when treatments of 0.006 Mn2+ %, 0.3 Mn2+ %, 0.05 VitB %, and 0.1 VitB % were applied. Best results for textural, sensory, and color properties were observed in samples produced by 0.006 Mn2+ + 0.5 VitB. The results showed that the addition of ions and vitamins in milk to reduce the incubation time was directly related to their concentration and their synergistic effects, and therefore their critical levels must be carefully taken into account.

关键词： nanoparticles   cancer diagnosis   treatment of cancer   nanotherapeutics   therapeutic nanoparticles  

摘要： Simple Summary The use of nanopharmaceuticals in chemotherapeutic regimens has become a promising approach for the treatment of most of the demanding types of cancers. Their in-depth physicochemical characterization plays an instrumental role in the quality control of a promising new medicine. The combined function of diagnosis and therapy in the same nanopharmaceuticals created the so-called nanotheragnostics, which have found a broad range of applications in this field. This review addresses the state of the art on the use of nanopharmaceuticals in cancer therapy and the latest challenges encountered in regulating these new medicines. Physicochemical, pharmacokinetic, and biopharmaceutical characterization tools play a key role in the assessment of nanopharmaceuticals' potential imaging analysis and for site-specific delivery of anti-cancers to neoplastic cells/tissues. If diagnostic tools and therapeutic approaches are combined in one single nanoparticle, a new platform called nanotheragnostics is generated. Several analytical technologies allow us to characterize nanopharmaceuticals and nanoparticles and their properties so that they can be properly used in cancer therapy. This paper describes the role of multifunctional nanoparticles in cancer diagnosis and treatment, describing how nanotheragnostics can be useful in modern chemotherapy, and finally, the challenges associated with the commercialization of nanoparticles for cancer therapy.