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关键词： Ultrasound processing   Structural property   Starch gelatinization   Pasting   Starch digestibility   Phenolics   Non-thermal processing  

摘要： Ultrasound technologies are increasingly used for modification of physicochemical properties of food systems. Effects of ultrasound (20 kHz, 750 W) up to 20 h on physicochemical properties of two varieties of sweetpotato flour were studied and compared with those of commercial wheat flour. Ultrasound induced structural modifications on starch granules mainly in the morphological changes of granules and reduction of the crystallinity. Longer treatment significantly decreased enthalpy change of gelatinization, pasting viscosities, gelling capacity, while increasing in vitro starch digestibility of raw flour. Besides, prolonged treatment reduced total phenolic contents and in vitro antioxidant activities of sweetpotato flours, mainly due to pyrolysis and release of hydroxyl radicals caused by cavitation. The extents of these changes were seen to depend on the treatment time and indicated degradation and modifications of the chemical components (e.g., starch and polyphenol) of flours. This study suggests that ultrasound processing as a non-thermal and energy-saving technique has potential to modify flour functionalities.

关键词： Orthogonal imaging   Laser backscattering   Silica particles   Essential oils   Physico-chemical characterisation  

摘要： The capacity of orthogonal imaging applied to laser-backscattering for characterising antimicrobial particles based on immobilised essential oils was tested. Different particles were synthesised using various particle and oils. Samples were characterised physico-chemically and by an imaging technique. The technique recorded the generated patterns because of the laser-particles interaction during the sedimentation process. The series of images were transformed into an orthogonal image. Data extraction varied depending on the fragmentation degree of image length. After the multivariate analysis, the physico-chemical results showed variability due to particle size. That variability diminished the effect of oils for large sizes. The imaging data collected these properties, which could be used to recognise both particle size and oil type. Thus the prediction of the properties was successful. The position in the physico-chemical space of variance was also predicted. Hence this technique could complement a low-cost method to evaluate the properties of functionalised particles with oils.

关键词： complex   1-(o-tolyl)biguanide   antimicrobial activity   biofilm   human cervical cancer  

摘要： New complexes of type [M(tbg)(2)]Cl-2 [tbg = 1-(o-tolyl)biguanide;M = Ni(II), Pd(II), and Pt(II)] were synthesized and characterized to develop new biologically active compounds. The features of the complexes were assigned from microanalytical and thermal data. The NMR, FT-IR, and UV-Vis spectra were established by comparison with HtbgCl. All complexes exhibit a square-planar geometry resulting from the chelating behavior of tbg. The HtbgCl and [Ni(tbg)(2)]Cl-2 complexes were fully characterized by single-crystal X-ray diffraction. The HtbgCl species crystallize in the monoclinic C2/c spatial group, while the Ni(II) complex adopts an orthorhombic Pna2(1) spatial group. The structure is stabilized by a complex hydrogen bonds network. The in vitro antimicrobial assays revealed improved antimicrobial activity for complexes in comparison with the ligand against both planktonic and biofilm embedded microbial cells. The most efficient compound, showing the largest spectrum of antimicrobial activity, including Gram-positive and Gram-negative bacteria, as well as fungal strains, in both planktonic and biofilm growth states was the Pd(II) complex, followed by the Pt(II) complex. The Pt(II) compound exhibited the most significant antiproliferative activity on the human cervical cancer SiHa cell line, inducing a cell cycle arrest in the G2/M phase.

关键词： Rabbit meat   Fatty acids   Amino acids   Minerals   Sage   Enterocin  

摘要： Higher rabbit meat consumption can be ensured by increasing of its quality due to its improved nutritional properties. The effect of enterocin M (EntM) and sage on growth performance, physico-chemical properties, fatty acid (FA), amino acid (AA), and mineral concentrations of rabbit meat was evaluated. Sixty-four rabbits (M91 meatline, both sexes) were divided into three experimental: E (EntM), S (sage), E + S (EntM + sage) groups and control group (C). The additives were administrated in drinking water during 21 days. Lower pH (E, S: P < 0.05;E + S: P < 0.001) and decrease in water content were noted in all experimental groups compared with controls (C). Higher values of lightness (L*), yellowness (b*), and redness (a*;except group E) were measured. The sage administration increased the fat and protein contents (P < 0.05), the meat energy value (S vs. C: P < 0.01;S vs. E and E + S: P < 0.05), the concentrations of arachidonic (P < 0.05), eicosapentaeonic (P < 0.05), and oleic acids (P < 0.01), magnesium (P < 0.05), and potassium (P < 0.01) content. The additives did not influence the rabbit meat AA composition. The sage diet inclusion could improve the quality of rabbit meat due to its higher protein, fat, and energy contents and enhance the PUFA and mineral content of rabbit meat. Moreover, the effect of EntM on meat color parameters, FA and AA composition, has not been tested in rabbits previously.

关键词： extrusion   adlay   component   microscopic structure  

摘要： This study investigated the changes in the structural and functional properties of various adlay starch-based polymers that occur during low moisture extrusion. The water absorption index, water solubility index, color, and morphological, pasting, and thermal properties of the adlay flours were investigated. Extrusion significantly decreased their contents (starch > protein > fiber > lipids). The color of the adlay flour darkened after extrusion, primarily due to the Maillard reaction and caramelization. Scanning electron microscopy revealed various cracks, pits, and holes on the surface of the extruded flour without defatting for both the extruded brown adlay and the extruded polished adlay. Extrusion caused molecular degradation of the extruded starch, decreasing its swelling power in hot water. The AH values (0.19-0.71 J/g) of the extrudates revealed that the starch granules were not fully gelatinized. These results provide a theoretical basis for further explorations of the interactions of adlay macromolecules by extrusion.

关键词： Probiotic   Biopolymers   Encapsulation   In vitro digestion   Freeze-drying   Rice milk   Soybean milk  

摘要： The effect of microencapsulation of L. acidophilus La-05 (8 log CFU/mL) by external ionic gelation technique in alginate (30 g/L;AM) and alginate coated with a low molecular weight chitosan solution (5 g/L;AC5M) on the survival of the freeze-dried probiotic culture during storage (7 degrees C;0, 7, 15, 30, 60, 90 and 120 days), and exposure to temperature (72, 85 and 90 degrees C), pH (2, 4, and 6), and NaCl (10, 15 and 20 g/L) were studied. Furthermore, vegan milks (soybean and rice milks) added with microencapsulated probiotic cultures were evaluated for the physicochemical characteristics and survival of the probiotic culture during refrigerated storage (7 degrees C;7 days) and in vitro digestion. Free cells were used as control. AM and AC5M showed similar microencapsulation yield ( > 90%) with uniform and spherical microparticles dispersed without agglomeration. Scanning electron microscopy showed that chitosan was able to cover the porous structure of the alginate particles, resulting in a more stabilized microparticle. The microencapsulation provided higher probiotic protection to storage, thermal treatment, NaCl and pH (decreases of similar to 1 log CFU/mL) compared to the free cells (decreases of similar to 3, 4, 2 and 3 log CFU/mL, respectively), and increased probiotic survival during refrigerated storage and in vitro digestion of vegan milks compared to free cells (decreases of similar to 1 and 4 log CFU/mL, respectively). Only microencapsulated probiotic cultures (AM and AC5M) maintained suitable probiotic counts ( > 6 log CFU/mL) during storage, exposure to stress conditions and simulated gastrointestinal digestion. Chitosan coating increased the probiotic survival in the vegan milks during refrigerated storage. Microencapsulation by external ionic gelation in alginate proved to be a suitable microencapsulation technique to improve the probiotic survival to storage, stress conditions (temperature, pH and NaCl) and simulated gastrointestinal conditions.

关键词： Co-amorphous   Atorvastatin   Naringin   Ball milling   Solvent evaporation   Quench cooling  

摘要： Purpose The goal of the study was to investigate the influence of processing methods on the physicochemical and pharmacokinetic properties of co-amorphous materials. Methods Co-amorphous formulations of atorvastatin (ATV) and naringin (NRG) in the molar ratio 1:1 were prepared by quench cooling (ANQC), solvent evaporation (ANSE), and ball milling (ANBM) and characterized by differential scanning calorimetry (DSC), powder X-ray diffractometry (XRPD), and Fourier transform infrared spectroscopy (FTIR). Further, the performance of prepared co-amorphous formulations was evaluated in vitro and in vivo. Results All processing methods yielded homogeneous co-amorphous formulation, which was confirmed by single glass transition (Tg) event and diffuse halo in DSC and XRPD, respectively. Irrespective of processing method employed, all co-amorphous formulations were found stable at 30 degrees C for 90 days in dry conditions (under vacuum). Significant improvement in the solubility of ATV was observed in ANQC and ANSE co-amorphous formulations, highest being 56-fold for the later. ATV from ANSE formulation showed highest drug release (97%), while surprisingly ANQC showed significantly lower ATV release as compared to the physical mixture. Amongst three preparation methods, solubility advantage of ANSE could translate into efficacious pharmacokinetic parameters, where the improvement in ATV exposure (AUC 0-t) and plasma concentration (Cmax) were found 4.5-fold and 7-fold, respectively, as compared to the physical mixture. Conclusion It was concluded that the preparation methods of co-amorphous formulations have a profound effect on physical properties like stability, physicochemical properties like solubility, dissolution rate, and pharmacokinetic properties like AUC and Cmax.

关键词： NPs   H2O2   Yb2O3   Cyclic voltammetry   Current   Potential  

摘要： Herein, a uniform spherical shaped Gd(III) doped Yb2O3 (Gd@Yb2O3) nanoparticles (NPs) was successfully synthesized via hydrothermal method for electrochemical detection of H2O2. The calcination effect and porosity of the materials well elaborated in the present work. The optical properties, size, morphological, thermal, sensing, surface and crystalline properties of synthesized materials were examined by several techniques. The enhanced electrocatalytic performance of Gd@Yb2O3 make the present sensor excellent towards the determination of *** anodic and cathodic peak current increased regularly with addition of H2O2 solution. The electrode coating surface was stable even after a number of electrochemical cycles and have high limit of detection (51 nM). Moreover, the present sensor was successfully employed for detection of H2O2 in real samples.

关键词： Protein   Benzoic acid   Stability   Solvent accessibility   Molecular dynamics calculations  

摘要： Carboxyl-modified substrates are the most common chemical moieties that are frequently used as protein defibrillators. We studied the stability of protein-benzoic acid complexes with bovine serum albumin (BSA), zein and lysozyme proteins using various computational methods. Structural model for zein was built using homology modelling technique and molecular docking was used to prepare complex structures of all three proteins with benzoic acid. Molecular dynamics calculations performed on these complex structures provided a strong support for the stability of protein-benzoic acid complexes. The results from various analyses including root-mean-square deviation (RMSD) and radius of gyration showed the stability and compactness of all proteins-benzoic acid complexes. Moreover, exploration of structural fluctuations in proteins revealed the stability of active site residues. Two potential binding modes of benzoic acid with all three proteins were identified via cluster analysis. The binding mode which was retrieved from top cluster containing 86-91% of total conformations displayed very strong binding interactions for zein, BSA and lysozyme proteins. In addition, the results of binding mode showed that various interactions, including hydrogen binding, hydrophobic and electrostatic interactions were important for the optimal binding of benzoic acid with the active sites of proteins. Exploration of solvent accessible surface area showed that lysozyme-binding cavity was more exposed to the surface as compared to the other two proteins. Free energy analysis of all protein systems showed the stability of protein-benzoic acid complexes with lysozyme and BSA relatively more stable than zein system. The results of our study provided important insights to the dynamic and structural information about protein-benzoic acid interactions with BSA, zein and lysozyme proteins. This work is important in enhancing the stability of therapeutic protein drugs loaded on carboxyl substrates.

关键词： Secondary metabolites   Soil quality   Ocimum   Bioactivity  

摘要： Ocimum has long been used as a medicinal plant, although little information is available about its bioactive ingredients, and the influence of soil properties on modulation of secondary metabolites in Ocimum has yet to be ascertained. In this study, we present a thorough survey of all potential metabolic compounds in O. sanctum and O. basilicum. In both species, certain compounds (e.g., quercetin, kaempferol, catechin, and S-adenosyl homocysteine) were detected coincidently. In the case of O. basilicum, other vital phenolic acids (e.g., ursolic, vanilic, coumaric, and syringic acids) were identified. The aqueous extracts (AEs) of Ocimum recorded decrease of 6-94% in the proliferation of pathogenic bacteria (e.g., Listeria monocytogenes, Staphylococcus sp., Salmonella sp., and Bacillus sp.). The AEs also showed effective antioxidant activity by reducing free radicals by a factor of 1.04-1.13. Root-zone soil samples of both Ocimum spp. were collected from strategic locations with varying levels of key soil attributes (e.g., soil organic carbon (SOC), microbial biomass carbon (MBC), urease, and phosphatase). At high levels of SOC, MBC, and soil enzymes, the bioactivity of Ocimum spp. was observed to be promoted, especially with respect to secondary metabolite expression, anti-pathogenic activity, and anti-oxidant properties. As such, the findings of strong correlations between secondary metabolite concentrations and bioactivity attributes in Ocimum suggest the potent role of soil quality in eliciting the production of secondary metabolite in association with bioactivity in Ocimum spp.