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关键词： Candida albicans   Antifungal activity   Toxicity   Nanoparticles   Cerium oxide   Inhibitory concentration  

摘要： Fungal infection is a public health problem. Antifungal agents resistance is often seen in common Candida albicans in the hospital environment. Nanoparticles have been reported in the literature as a promising development of health products. The toxicity, antioxidant and antifungal activity of cerium oxide nanoparticles (CeNP) were evaluated. After synthesis and characterization of the physicochemical properties, the new CeNP was evaluated by biological tests of antifungal activity. The antioxidant activity of CeNP was evaluated by scavenging free radicals of 1,1-diphenyl-2-picrylhydrazyl hydrate (DPPH). The DPPH scavenging activity was monitored by % color inhibition the absorbance. In vivo acute toxicity studies of CeNP were carried out by oral administration in mice (300 and 2000 mg/kg, n = 3/ group), and by brine shrimp (Artemia salina) model (0.001-25 mg/ mL, n = 10/ group). CeNP was able to interfere in the fungal growth, depending on the strain and dosage used. Acute lethal dose 50% is greater than 2000 mg/kg and CeNP did not induce toxicity for A. salina. Antioxidant activity was not significant. The current antifungal and toxicity features results support the use of CeNP as antifungal agent against Candida albicans strains, which may find applications in biotechnology and biomedical area in the development of a new nano-biomaterial for clinical applications. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of King Saud University.

关键词： Yoghurt   Probiotic   Soymilk   Milk   Microstructure   Physicochemical characteristics  

摘要： Soymilk yoghurt is an option to consumers who are allergic to cow's milk yoghurt. Probiotics can provide gut health. The objective of this study was to investigate the physicochemical characteristics, including pH, colour, firmness and syneresis of yoghurt made from soymilk and cow's milk as affected by the addition of probiotics during storage at 4 degrees C for 28 days at 7-day intervals. Microstructure and bacterial populations were also determined. Two types of yoghurt were prepared. The first type was prepared with the additions of commercially available yogurt starter containing Lactobacillus delbrueckii ssp. bulgaricus (LB) and Streptococcus thermophilus (ST). The second type was prepared with the same yogurt starters plus three probiotics, including Bifidobacterium animalis subsp. lactis BB-12 (BB), L. acidophilus La-5 (LA), and L. rhamnosus (LGG). Probiotics reduced syneresis and increased compact network of soymilk yoghurt significantly (p < 0.05) and shortened the time needed to reach pH 4.5 in both cow's milk and soymilk yogurts. During storage, the pH of cow's milk yoghurts slightly decreased (4.37-4.26 with probiotics and 4.54 to 4.33 without probiotics), however, the pH of soymilk yoghurts remained relatively constant. The firmness of yoghurt made from cow's milk was significantly decreased with the addition of probiotics, however, it remained stable in soy milk yoghurt during storage. Soymilk yoghurt (34-50 g force during compression) was generally firmer than cow's milk yoghurts (9.8-12.5 g force). The cow's milk yogurt had slightly higher counts of ST, LB and LA than soymilk yogurt, but the count of BB in soymilk yogurt is significantly higher than that in cow's milk yogurt.

关键词： acetic acid   cassava starch   crystallinity   physicochemical properties   ultrasonication  

摘要： Cassava starch films are fabricated with acetic acid treatment and ultrasonication. Different ultrasound power levels from 200 to 750 W are used and the effects of ultrasonication on the morphology, microstructures, and properties of the starch-acetic acid films are investigated. Scanning electron microscopy shows a cohesive and compact structure of the films resulting from ultrasonication. X-ray diffraction analysis reveals that the crystalline index is decreased by acid treatment and increased by ultrasonication. The tensile strength and elongation at break of the films first increase and then decrease with increasing ultrasound power level. Ultrasonication also results in higher opacity, higher water barrier performance, and lower water adsorption of the films. Thus, the results show that ultrasonication can be used as a simple and efficient way to modify the morphology, microstructure, and performance of starch-acetic acid films to better meet the application needs.

关键词： 4-oxo-2-sulfanylidene-1   3-thiazolidine   amide   drug likeness   antitumor activity  

摘要： 2-[5-(4-Bromobenzylidene)-4-oxo-2-sulfanylidene-1,3-thiazolidin-3-yl]-3-methylbutanoyl chloride was reacted with ethanol and amines to obtain the corresponding ester and amides, and their physicochemical properties and drug likeness were predicted in silico. The synthesized compounds were evaluated for their in vitro antitumor activity and were found to exhibit a moderate activity against most human cancer cell lines. The most sensitive cancer cell line was CCRF-CEM leukemia with respect to 2-[(5Z)-5-(4-bromobenzylidene)-4-oxo-2-sulfanylidene-1,3-thiazolidin-3-yl]-N-[2-hydroxy-2-(4-hydroxyphenyl)ethyl]-N,3-dimethylbutanamide.

关键词： Aedes aegypti   Breeding site   Physicochemical parameter   Bacterial community  

摘要： Aedes aegyptidevelop in aquatic habitats in which mosquito larvae are exposed to physicochemical elements and microorganisms that may influence their life cycle and their ability to transmit arboviruses. Little is known about the natural bacterial communities associated withA. aegyptior their relation to the biotic and abiotic characteristics of their aquatic habitats. We characterized the physicochemical properties and bacterial microbiota ofA. aegyptibreeding sites and larvae on Guadeloupe and in French Guiana. In addition, we explored whether geographic location, the type of breeding site and physicochemical parameters influenced the microbiota associated with this mosquito species. We used large-scale 16S rRNA gene sequencing of 160 breeding sites and 147 pools ofA. aegyptilarvae and recorded 12 physicochemical parameters at the sampled breeding sites. Ordination plots and multiple linear regression were used to assess the influence of environmental factors on the bacterial microbiota of water and larvae. We found territory-specific differences in physicochemical properties (dissolved oxygen, conductivity) and the composition of bacterial communities inA. aegyptibreeding sites that influenced the relative abundance of several bacteria genera (e.g.,Methylobacterium,Roseoccocus) on the corresponding larvae. A significant fraction of the bacterial communities identified on larvae, dominated byHerbiconiuxandMicrovirgagenera, were consistently enriched in mosquitoes regardless the location. In conclusion, territory-specific differences observed in the biotic and abiotic properties ofA. aegyptibreeding sites raise concern about the impact of these changes on pathogen transmission by differentA. aegyptipopulations.

关键词： BLG AB   bovine beta-lactoglobulin isoform AB mixture   BLG B   bovine beta-lactoglobulin isoform B   rBLG B   recombinant bovine beta-lactoglobulin isoform B with additional N-terminal M   sBLG B   recombinant bovine beta-lactoglobulin isoform B with N-terminal L1A/I2S substitutions   AUC   analytical ultracentrifugation   DLS   dynamic light scattering   DNPH   2,4-dinitrophenylhydrazine   DiTyr   dityrosine   DTNB   5,5-'Dithio-bis-(2-nitrobenzoic acid)   DTT   Dithiothreitol   Gua-HCl   guanidine hydrochloride   OPA   ο-phtalaldehyde   PMSF   phenylmethylsulfonylfluoride   PTM   post-translational modifications   NAC   N-acetyl-   l   -cysteine   NFK   N-formylkynurenine  

关键词： Porcine plasma   Hydrolysates   Pork sausage   Texture improvement   Cold storage  

摘要： This study evaluated the effect of porcine plasma hydrolysates (PPH) on the physicochemical, antioxidant, and antimicrobial properties of emulsion-type pork sausages. Five levels of PPH were added to sausages (CON, 0 g/ kg;T1, 5 g/kg;T2, 10 g/kg;T3, 15 g/kg;and T4, 20 g/kg) and their chemical composition, purge loss, lipid oxidation, microbial count, pH, color, texture, and sensory properties were compared on day 1 and after 4 weeks of cold storage. At 4 weeks of storage, hardness, cohesiveness, and gumminess were highest in T3 (P < 0.05). The peroxide value increased in all treatments during the 4-weeks of storage (P < 0.05);however, it was not significantly different between CON, T2, and T3 (P > 0.05). The total aerobic plate count was the lowest in T4 at week 4 (P < 0.05). Therefore, PPH addition could improve the texture of the emulsion-type pork sausages, and an antimicrobial effect was expected following exposure to at least 20 g/kg PPH.

关键词： Niosome   Simvastatin   Antibacterial activity   MTT assay  

摘要： Niosomes, as a kind of drug delivery system, is widely used for the topical delivery of lipophilic drugs. Optimization of niosomes plays an essential role in enhancing their therapeutic efficiencies. This study aims to prepare an optimized niosomal formulation of simvastatin (nSIM), a lipophilic member of statins, through the experiment (Response Surface methodology). Optimized niosomes were characterized in size, polydispersity index (PDI), entrapment efficiency (EE), stability, releasing pattern, and antimicrobial activity. The different molar ratio of surfactant and cholesterol were applied to prepare various formulation of simvastatin loaded niosome. Mean particle size and size distribution were analyzed by dynamic light scattering. Antibacterial activity was determined by MIC and MBC tests against Staphylococcus aureus and Escherichia coli. The release rate of simvastatin from noisome nanoparticles was studied by the Franz diffusion cell method. The release pattern was studied through zero order, first order, Higuchi, Korsmeyer-Peppas, and Hixson-Crowell kinetics models. Optimized niosomes were obtained by span 80, drug to cholesterol ratio of 0.4 with 7 min sonication time. Mean particle size, PDI, zeta potential, and entrapment efficiency (EE%) of optimized nSIM were obtained about 168 nm, 0.34, -32.40, and 96 %, respectively. The niosomes significantly decreased the drug's releasing rate and enhanced antibacterial activity against S. aureus and E. Coli. It was found that the release pattern of drug followed the Higuchi kinetic model which means drug release is by diffusion. Overall, our findings indicated that the prepared simvastatin loaded niosomes showed good stability and biological properties than free drug. Our study suggests that niosomal formulation could be considered as a promising strategy for the delivery of poor water-soluble drugs that enhance antibacterial activity.

关键词： cold plasma   milk   physicochemical properties   sterilization  

摘要： The aim of this study was to evaluate the mechanism of dielectric barrier discharge cold plasma (DBD-CP) sterilizing function on milk and to analyze the influences of DBD-CP on the structure and physicochemical performance of milk. It was verified that DBD-CP sterilizing function resulted in a broken bacterial cell membrane, reduced activity of metabolic enzymes, and bacterial DNA destruction. DBD-CP treatment would bring in some more stabilized structures obtained from scanning electron microscopy and Fourier-transform infrared spectroscopy. The values of color, viscosity, pH, and titratable acidity showed an acceptable physicochemical property with DBD-CP treatment at 70 V (120 s) and 80 V (120 s). Therefore, it indicated that DBD-CP could be used as a new sterilization method for milk.

关键词： whey protein microgel   reduced-fat Cheddar cheese   anthocyanin carrier  

摘要： Reduced-fat foods have become more popular due to their health benefits;however, reducing the fat content of food affects the sensory experience. Therefore, it is necessary to improve the sensory acceptance of reduced-fat foods to that of full-fat equivalents. The aim of this study was to evaluate the effect of adding whey protein microgels (WPM) with an average diameter of 4 mu m, or WPM with adsorbed anthocyanins [WPM (Ant)] on the textural and sensory properties of reduced-fat Cheddar cheese (RFC). Reduced-fat Cheddar cheese was prepared in 2 ways: (1) by adding WPM, designated as RFC+M, or (2) by adding WPM (Ant), designated as RFC+M (Ant). For comparison, RFC without fat substitutes and full-fat Cheddar cheese were also prepared. We discovered that the addition of WPM and WPM (Ant) increased the moisture content, fluidity, and meltability of RFC, and reduced its hardness, springiness, and chewiness. The textural and sensory characteristics of RFC were markedly inferior to those of full-fat Cheddar cheese, whereas addition of WPM and WPM (Ant) significantly improved the sensory characteristics of RFC. The WPM and WPM (Ant) showed a high potential as fat substitutes and anthocyanin carriers to effectively improve the acceptance of reduced-fat foods.