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关键词： Halophyte plants   Sarcocornia perennis   Drying process   Kinetic   Physico-chemical properties   FTIR-ATR  

摘要： The Sarcocornia genus is an extreme salt-tolerant plant that can be cultivated in saline habitats almost worldwide. To preserve Sarcocornia perennis, convective drying experiments were conducted and their effects on the physico-chemical properties and phenolic content of the plant were studied using conventional and vibrational spectroscopy techniques. The drying process of Sarcocornia perennis at temperatures of 40 degrees C, 50 degrees C, 60 degrees C and 70 degrees C revealed three periods of convective drying process with drying times ranging between 4.5 and 24.9 h, respectively to higher and lower temperatures. The heating-up period can be neglected as compared with the drying process, and the duration of constant rate period, as a percentage of the total drying time, ranged between 34 and 20% respectively at 40 degrees C and 70 degrees C. The Modified Page model was proposed to describe the drying process at the different temperatures. From a nutritional point of view, this halophyte plant may be considered as a good source of fibres, phenolic compounds and natural minerals, such as sodium, potassium, calcium and magnesium. The convective drying, in the temperature range currently used, was found to preserve the colour, nutritional characteristics and phytochemical value of Sarcocornia perennis. These results were confirmed by FTIR-ATR and highlight the potential use of the dried plant in novel food products.

关键词： Black glutinous rice wine   Microbial communities   Physicochemical properties   Volatile components   Correlation analysis   High throughput sequencing  

摘要： Black glutinous rice wine (BGRW) is a popular traditional Chinese rice wine;however, the flavors profiles associated with microbiota changes during its fermentation have not yet been evaluated. In this study, we explored the correlations between microbial communities with physicochemical properties and flavor components during BGRW fermentation. High-throughput sequencing was used to identify the microbial community composition of BGRW at different fermentation stages, and physicochemical properties and volatile flavor compounds (VFCs) were identified via fermentation features testing and headspace solid phase microextraction gas chromatography mass spectrometry. First, we revealed Pantoea and Kosakonia predominated bacterial genera the early stage of BGRW fermentation, Leuconostoc, Pediococcus, Bacillus, and Lactobacillus predominated bacterial genera the later stage, while Rhizopus and Saccharomyces were the predominant fungal genera throughout fermentation. Second, total sugars, titratable acids, pH, ethanol, amino acid nitrogen, and 43 VFCs were detected during fermentation. Twenty-three VFCs were differentially produced according to the linear discriminant analysis effect size method. With the increase of the fermentation time, the kinds and contents of esters and alcohols were also increased, while acids decreased. Moreover, 12 microbial genera, Lactococcus, Pediococcus, Leuconostoc, Lactobacillus, Cronobacter, Pantoea, Weissella, Enterococcus, Rhizopus, Myceliophthora, Cystofilobasidium, and Aspergillus were found to be highly correlated (vertical bar rho vertical bar 0.7 and P < 0.05) with physicochemical properties and VFCs, by redundancy analysis (RDA) and two-way orthogonal partial least squares (O2PLS) analysis. Ultimately, based on the results, a metabolic map of dominant genera in BGRW was established. Our findings provided detailed information on the dynamic changes of physicochemical properties and VFCs and selection of beneficial strains to improve

关键词： Ru(II) polypyridyl complexes   lipophilicity   antimicrobial activity   cytotoxicity   confocal microscopy  

摘要： In search for efficient chemotherapeutic agents, we have synthesized a novel MBIP 2-(4-methylbenzoate)-1H-imidazo[4,5-f][1,10]phenantroline and its Ru(II) polypyridyl complexes of the general formula [Ru(N-N)(2)(L)](2+) (where N-N = phen (1,10-phenanthroline), bpy (2,2MODIFIER LETTER PRIME-bipyridine), dmb (4,4MODIFIER LETTER PRIME-dimethyl-2,2MODIFIER LETTER PRIME-bipyridine), and L = MBIP. All complexes have been characterized by analytical and spectroscopic methods. Physico-chemical properties of the synthesized complexes such as stability and lipophilicity have been studied. Interaction of Ru(II) complexes with calf-thymus DNA (CT-DNA) has been explored by different spectrophotometric methods. Spectral and viscosity data indicate that all the complexes are probably involved in intercalative binding with DNA. These complexes can cleave pBR322 DNA efficiently via oxidative pathway involving singlet oxygen under photoirradiation. The DNA molecular light switch on and off performance of Ru(II) complexes has been studied. According to antimicrobial activity assays the complexes are potential agents against gram positive and gram negative bacteria. In vitro cytotoxicity has been evaluated by MTT assay against HeLa cell lines, being compared to cisplatin. The live cell imaging and lipophilicity results have revealed that the complexes can possibly cross the cell membranes and accumulate in the nucleus. The cellular localization of Ru(II) complexes determined by their lipophilicity can probably affect their anticancer efficacy and mechanism of action.

关键词： antibacterial activity   microorganisms   visible spectra   cancer   X-ray diffraction   cellular biophysics   nanomedicine   ultraviolet spectra   nanoparticles   transmission electron microscopy   nanofabrication   field emission scanning electron microscopy   Fourier transform infrared spectra   particle size   magnesium compounds   space groups   toxicology   physicochemical properties   structural properties   Rheum emodi root extract mediated magnesium hydroxide nanoparticles   bio-inspired experimental technique   field emission scanning electron microscopy   transmission electron microscopy   TEM   Fourier transform infrared spectroscopy   FTIR spectroscopy   ultraviolet-visible spectroscopy   X-ray diffraction   hexagonal crystal symmetry   space group P-3m1   space group no   164   Rietveld refinement technique   nanosize formation   plant metabolites   spherical shape   antibacterial potential   cytotoxic potential   reducing agent   anthraquinones   stabilising agent   Gram-positive bacteria   Gram-negative bacteria   Escherichia coli   Staphylococcus aureus   MDA-MB-231 human breast cancer cell lines   Mg(OH)(2)  

摘要： In the present investigation, Rheum emodi roots extract mediated magnesium hydroxide nanoparticles [Mg(OH)(2) NPs] through the bio-inspired experimental technique were synthesised. Mg(OH)(2) NPs were characterised by using various characterisation techniques such as field emission scanning electron microscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and ultraviolet-visible spectroscopy. The formation of Mg(OH)(2) NPs was confirmed by X-ray diffraction. The structural analysis confirmed the hexagonal crystal symmetry of Mg(OH)(2) NPs with space group P-3m1 and space group no. 164 using the Rietveld refinement technique. TEM micrographs illustrated the nano-size formation of Mg(OH)(2) NPs of spherical shape and size similar to 14.86 nm. With the aid of FTIR data, plant metabolites such as anthraquinones have been identified as a stabilising and reducing agent for the synthesis of biogenic Mg(OH)(2) NPs. The synthesised Mg(OH)(2) NPs showed antimicrobial and cytotoxic potential against Gram-negative and Gram-positive bacteria such as Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) and MDA-MB-231 human breast cancer cell lines.

关键词： Okara fibers   Ultrasound treatment   Structure   Physicochemical properties  

摘要： This work focuses on the effects of different ultrasound power densities on the microstructural changes and physicochemical properties of okara fibers, which are composed of carbohydrate-based polymers. Okara suspensions were treated with ultrasound at different power densities (0, 1, 2, 3, 4, and 5 W/mL) for 30 min, after which the ultrasound-treated okara were hydrolyzed by trypsin to obtain okara fibers. The ultrasound treatment of the okara fibers induced structural disorganization and changes, evidenced mainly in their morphological characteristics and their relative crystallinity degrees. Increasing the ultrasound power broke the okara fibers into flaky and stacked structures. When the ultrasound power density reached 4 W/mL, the parenchyma became compact and the hourglass structure fractured. The mean particle size of the okara fiber was reduced from 82.24 mu m to 53.96 mu m, and the homogeneity was enhanced significantly. The relative crystallinity of the okara fibers was reduced from 55.14% to 36.47%. The okara fiber surface charge decreased when the ultrasound power was increased. However, after ultrasound treatment at 4 W/mL (800 W), the okara fiber suspension exhibited the highest viscosity value and a higher swelling capacity, water-holding capacity, and oil-holding capacity. Therefore, the results indicated that the selection of processing conditions for okara fibers is critical and that okara fiber modification using a high ultrasound treatment might improve their use in potential applications.

关键词： High-pressure homogenization   Oyster protein gel   Conformation   Rheology  

摘要： For better application of oyster protein (OP), high-pressure homogenization (HPH) (0, 20, 40, 60, 80 or 100 MPa) was used to explore the physicochemical changes and enhance the gelling properties effectively. The results showed that HPH altered secondary structures of OP with a decrease of alpha-helixes but an increase of beta-sheets;as well as tertiary structures with higher free sulfhydryl (SHF) and higher surface hydrophobicity (H-0). Compared to the control, the reduced mean particle size and the increased surface net charge promoted the solubility of OP after HPH treatment. Moreover, HPH also changed static rheological properties of OP suspensions with fewer shear stress values at 1 s(-1) (tau(1)) but higher flow index values (n). Stronger HPH significantly improved gelling properties and enhanced the intensity and stability of OP gels. These might be ascribed to changes in structures and the promotion of solubility. The results suggested a way to expand the utilization of oyster protein.

关键词： Particle size analysis  

摘要： Microbiological, physicochemical, and textural characteristics, and oxidative stability was investigated of butter produced from raw cream treated with high-pressure homogenisation (HPH) at 0 (control), 10, 20, 30, 50, or 70 MPa. HPH treatment of cream increased lightness and decreased yellowness of butter. Firmness of all butter samples was between 97 (control) and 380 N (70 MPa). HPH decreased the spreadability of butter dependent on increasing pressure. A monomodal fat particle size distribution was determined in all butter samples;D[3.2] ranged from 25.25 to 125.5 mu m and HPH decreased average particle size compared with the control. The induction time of butter ranged from 27.40 (control) to 39.61 h (70 MPa). Above 50 MPa, Salmonella, and yeast and moulds were completely inactivated whilst coliforms and staphylococci were not detected in butter from HPH treated cream at 70 MPa, indicating that HPH can improve the microbial quality of butter produced from raw cream. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： sorbent   sorption   1   8-bis[2-(diphenylphosphorylmethyl)phenoxy]-3   6-dioxaoctane   lead   isotherm   kinetics   selectivity  

摘要： The sorption of lead by an impregnated type sorbent based on the phosphorylpodand, 1,8-bis[2-(diphenylphosphorylmethyl)phenoxy]-3,6-dioxaoctane, was studied. Sorption isotherms were plotted, as well as the data on kinetics, selectivity, and dynamics of sorption were obtained. The phosphorylpodand-based sorbent attains the sorption equilibrium of lead extraction with a high rate. The maximum sorbent capacity was achieved when the equilibrium concentration of lead in solutions was more than 150 mg L-1. The 1,8-bis[2-(diphenyl-phosphorylmethyl)phenoxy]-3,6-dioxaoctane-based sorbent shows a high selectivity for lead sorption from neutral solutions. The output curve of lead sorption was plotted. The dynamic exchange capacity and total dynamic capacity of the obtained sorbent were determined.

关键词： Actinobacteria   Antibiotics   Bioactive secondary metabolites   Cryptic pathways   Elicitors   Promicromonospora kermanensis  

摘要： The drug discovery rate is dramatically decreasing due to the rediscovery of known compounds. Genome mining approaches have revealed that a large portion of the actinobacterial genome that encodes bioactive metabolites is cryptic and not expressed under standard lab conditions. In the present study, we aimed to induce antibiotic encoding biosynthetic genes in a member ofMicrococcalesas a new species ofPromicromonospora,Promicromonospora kermanensis, by chemical and biological elicitors as it was considered to produce numerous valuable bioactive metabolites based on the whole genome results. Induction has been done via chemical (antibiotics, histone deacetylase inhibitors (HDAIs), rare earth elements (REEs), fatty acid synthesis inhibitors, and extreme pH changes) and biological elicitors (live and dead Gram-positive and negative bacteria). The results showed that valproic acid (as HDAIs), DMSO, lanthanum chloride (as REE), triclosan (as fatty acid synthesis inhibitors), alkaline pH, and supernatant ofPseudomonas aeruginosaUTMC 1404 culture could act as stimuli to provoke antibacterial synthetic pathways inPromicromonospora kermanensisDSM 45485. Moreover, it was revealed that eliciting agents in cell filtrated ofP. aeruginosaculture is resistant to detergent, acidic, and basic condition and have amphipathic nature. The inducing effect of alkaline pH on metabolite induction ofActinobacteriawas first reported in this study. In the follow-up studies, the induced antibacterial producing clusters can be subjected to the characterization, and the implemented approach in this study can be used for metabolites induction in other selected species.

关键词： Wet-media milling   Tapioca starch   Myofibrillar protein gel   Micro- and nanoparticles   Lamellar structure   Texture  

摘要： This study investigated the effect of wet-media milling on the physicochemical properties of tapioca starch (TS) and the relationship of these properties with the texture and microstructure of fish myofibrillar protein (MP) gel. The proposed wet-media milling was shown to linearly increase the transmittance of wet-media milled TS (WM-TS) suspensions and gradually induce the Tyndall effect, leading to an efficient reduction of the particle size from micro-scale (14.49 mu m) to nano-scale (140 nm), an increase in specific surface area and dispersion stability, and a decrease in zeta-potential, gelatinization temperature and viscosity. Among these properties, particle size, specific surface area and zeta-potential showed an extremely significant correlation with the texture of MP/WM-TS composite gel. Furthermore, milling increased the O/C ratio to expose more C-O bonds on the surface of WM-TS, which was well correlated with the enhanced texture of the MP/WM-TS composite gel. Additionally, milling disrupted the granular, crystalline and lamellar structures of TS, and transformed the TS granules from spherical state to heterogeneous state and then to homogeneous state, with a surface-to-mass fractal transition, contributing to the continuity of microstructures and compatibility of MP/WM-TS gels. Overall, the texture of MP/WM-TS gel was significantly affected by particle size and surface features (including specific surface area, zetapotential and the exposure of O element) rather than the dispersion stability and viscosity of starch slurry.