Beshiru, AbeniIgbinosa, Isoken H.Igbinosa, Etinosa O.
6页
查看更多>>摘要：The present study was carried out to determine and characterize the virulence and antimicrobial resistance profile of S. aureus from ready-to-eat (RTE) shrimp. A total of 720 RTE shrimp samples from open market in Delta State Nigeria were assessed for the virulence and antimicrobial characteristic profile of S. aureus using classical and molecular biology method. All S. aureus isolates in this study were positive for DNase, beta-hemolysis, and coagulase activity phenotypically. A total of 21 (39.6%), 15 (28.3%), 10 (18.9%) and 7 (13.2%) S. aureus isolates were strong, moderate, weak and negative to biofilm formation respectively. A total of 86.8% were resistant to >3 antibiotics with 52.8% of the isolates resistant to >10 antibiotics. Multiple antibiotic resistant index ranged from 0.05 to 0.96. The most prevalent virulence determinants in this study includes 53 (100%) for coa, hla, icaA, icaB and spa. Some prevalent toxins genes include sea 29 (54.7%), see 26 (49.1%), tsst-1 11 (20.8%) and pvl 24 (45.3%). Occurrence of some antibiotic resistance genes screened based on their phenotypic resistance profile is as follows: mecA 53/53 (100%), tetK 44/44 (100%) and cat::pC194 31/31 (100%). Findings from this study pinpoint the role of contaminated seafood in the spread of drug resistant pathogenic S. aureus strains representing an important public health risk.
Walayat, NomanXiong, ZhouyiXiong, HanguoMoreno, Helena M....
8页
查看更多>>摘要：The aim of this study was to investigate the impact of egg white protein (EWP) and beta-cyclodextrin (beta CD) mixture (3:1) on the structural and functional properties of myofibrillar proteins (MP) from silver carp during 60 days of frozen storage. Different concentrations of EWP-beta CD were prepared and incorporated with MP. It was analyzed that alpha-helix content significantly decreased (P < 0.05) during frozen storage. EWP-beta CD substantially enhanced the stability of alpha-helix content with the minimum increase of beta-turn and random coils. Furthermore, rheological studies revealed that MP with increased EWP-beta CD concentrations (4 and 6%) improved the inter-molecular protein interactions and enhanced the viscoelastic properties during the gelation process. Moreover, this addition improved the textural properties compared to control. It was also observed from microstructural analysis that MP gelling properties were decreased, which showed coarser and porous structure in control MP (0%). Meanwhile, MP gel treated with EWP-beta CD (6%) showed a more compact and well-established network of proteins. All experimental analysis confirmed that EWP-beta CD (6%) showed better cryoprotective properties in the preservation of the functional and structural properties of silver carp MP during frozen storage, and could be effective in the industrial storage of fish and associated products.
查看更多>>摘要：This study intended to determine whether edible microalgae can play an active role as an anti-virulence agent for enteropathogens. It showed that Chlorella variabilis (ATCC PTA 12198) are able to inhibit the production of the virulence factors in pathogenic Vibrio cholerae strains, the causative agent of cholera cases. Total lipid extract from C. variabilis (TLCV) was able to suppress the cholera toxin (CT) production in multidrug-resistant variant V. cholerae strains without affecting their growth. Cell-cytotoxicity induced by cholera toxin was also arrested in the presence of TLCV. Further, in vivo study in the gut of Artemia salina showed slightly less colonization of V. cholerae in the presence of TLCV. GC-MS analysis of the TLCV revealed the presence of saturated and unsaturated fatty acids include 9-cis,12-cis-Linoleic acid (linoleic acid), 9,12 Octadecadienoic acid (linolenic acid), cis, cis, cis-6,9,12-Octadecatrienoic acid (gamma-linolenic acid), cis-8,11,14-Eicosatrienoic acid (dihomo-gamma-linolenic acid) and cis-9-Octadecenoic acid (oleic acid). More specifically the aforesaid formulation works against most recent variant multidrug-resistant V. cholerae strain causing severe diarrhea. Thus, edible microalgae can a valuable natural source which possesses great potential to be developed as functional food ingredients and pharmaceutical products for reducing cholera.
查看更多>>摘要：Malaxation represents a critical and deeply studied step of the virgin olive oil extraction process due to its influence on yield and quality. Nonetheless, few experimental works have been focused on the mechanical aspects of the malaxer machine itself, with the aim of increasing its performance. In this framework, we investigated the effects of design changes of the rotating parts of the malaxer machine on the oil yield and on the virgin olive oil quality, antioxidants and volatile compounds.
Abballe, CarolineLeme Gomes, Fernanda MoralezLopes, Beatriz DezembroFerreira de Oliveira, Ana Paula...
9页
查看更多>>摘要：Contamination of cocoa and its derived products by polycyclic aromatic hydrocarbons (PAHs) may occur due to high roasting temperatures and/or the presence of smoke during drying. Some PAHs are considered carcinogenic and genotoxic. Thirteen PAHs were investigated during cocoa processing. Two cocoa beans samples were used, with and without presence of smoke during drying. In both, an initial contamination was detected, 1.78 mu g/kg for non-smoked beans and 66 mu g/kg for smoked cocoa beans. After roasting, a decrease in contamination was observed. Levels detected in derived products were from not detected (shell) to 2.08 mu g/kg (cocoa butter) for non-smoked beans and 5.2 mu g/kg (cocoa powder) to 136 mu g/kg (shell) for smoked beans. Mass balance showed that, for non-smoked cocoa beans, PAHs were transferred after pressing in equal proportions to cocoa butter (34%) and powder (37%). Smoked samples presented a large portion of PAHs in the shells (31%) and, after pressing, compounds remained mainly in the cocoa butter (43%). A tendency for PAHs to migrate to cocoa butter was observed. Drying cocoa beans without contact with smoke could reduce contamination and, therefore, human exposition to potentially carcinogenic and genotoxic compounds.
查看更多>>摘要：Protein and water modification in pork Longissimus dorsi (LD) pressurized at 200-400 MPa (5 min, 4 degrees C) followed by storage at -20 degrees C for up to 84 days were analyzed by complementary methodologies. Changes in proteins depended to a larger extent on storage time than pressure levels. High pressure (HP) improved drip loss by 35% after 84 days of storage. However, the meat's ability to retain water upon mechanical force (expressible moisture) was unaffected by both HP treatment and storage. No free water was present in the meat (due to drip loss), only immobile water and a larger fraction of water entrapped in the myofibrillar network were present. The water mobility after thawing was not affected as such by HP treatment and frozen storage. HP treatment and frozen storage results in a highly dynamic protein-water system, whereby protein and water molecules compete for H-bonding sites, consequently affecting the water binding.
查看更多>>摘要：Consumers are increasingly demanding healthier and natural foods made from whole grains. In view of this, a multigrain functional beverage was made using minor millets such as barnyard, foxtail and kodo millet. Millets are rich in dietary fibre, B vitamins and micronutrients like magnesium, iron and have low glycaemic index. Roasted millets were extracted with water and filtered to obtain the beverage. An appropriate ratio of all grain was obtained from D-optimal mixture design. Accordingly, grain amount was varied from 5 to 8 g, 8-12 g, 6-9 g for barnyard, foxtail and kodo millet respectively. The ratio was selected based on pH, phenolic content, antioxidant activity and sensory overall acceptability of resultant multigrain beverages. Beverage was treated with alpha-amylase enzyme, fructooligosaccharide, galactooligosaccharide, and maltitol to improve the sensorial properties. The final multigrain functional beverage was prepared from 7 g barnyard, 10 g foxtail and 8 g of kodo millet along with 1.2 g/100 g w/v of fructooligosaccharide, containing 5.72 g/100 g total dietary fibre, 47.69 mg ferulic acid equivalents (FAE)/100 mL total phenolic content with a prebiotic activity of 1.56 and 45.07 of glycaemic index (GI) which can be categorized as functional low GI beverage (GI < 55).
查看更多>>摘要：The properties of chitosan films can be modified by changing the solvent type, attributing to the different interaction patterns between chitosan and acids. However, little is known about how these interactions affect the structure and properties of chitosan films. In this work, the influence of acid type on the structure and properties of chitosan films was studied by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). FTIR spectra showed that the ionic interactions and hydrogen bonding could occur between chitosan and acid ions. Structural analysis revealed that chitosan was partially crystalline in hydrochloric and acetic acid films, whereas it was amorphous in lactic and citric acid films. DSC result indicated that the glass transition temperature of chitosan was much lower in citric acid film with low water content than in all the other films, suggesting that the citrate ions interacted more strongly with chitosan. A melting transition appeared in hydrochloric and acetic acid films. In addition, the tensile strength of these films decreased with an increase in the volume of acid. These observations indicate that the choice of a proper solvent for chitosan may be desirable for certain special applications.
Monteiro, Gean CharlesMinatel, Igor OtavioPimentel Junior, AdilsonGomez-Gomez, Hector Alonzo...
8页
查看更多>>摘要：Grape pomace is the main residue from juice and wine industries, and their derived products such as flours, can be a rich source of phenolic compounds and antioxidants. The overall objective of this study was to assess the phenolic compounds, antioxidant capacity, biogenic amines, and amino acids in flours obtained from grape pomace. Four cultivars ('Niagara Rosada', 'Bordo', 'BRS Violeta', and 'IAC 138-22 Maximo') were used, isolated or as blends, for juice production and from the resulting pomace, flours were produced. All flours assessed, independently of the cultivar or blend, showed valuable potential to addition in new products. The lowest levels of phenolic compounds and antioxidant capacity were observed in the flour produced entirely from cultivar 'Niagara Rosada'. However, when 'Niagara Rosada' was incorporated in blends with other cultivars, flours with increased levels of phenolic compounds and antioxidant capacity were obtained. The flour production gives a better destination for industrial waste, since these flours can be used for food, cosmetic, and pharmaceutical industries as additives or supplements to improve the antioxidant and bioactive content of their products.
查看更多>>摘要：Curcumin has phenomenal medicinal properties but is insoluble in water which restricts its bioavailability. Here, we report utilization of tragacanth gum for delivery of curcumin by developing a stable gum-curcumin (GC) suspension using microfluidization. Microfluidization of GC suspension was performed at 100 & 200 MPa pressure with 1-12 processing passes. Results indicated decrease in particle size with increase in number of microfluidization passes (303 nm after 100 MPa/12th pass with 1.5 g/dL tragacanth concentration). SEM of control and TEM of 100 MPa/12th pass sample showed distinct differences in the morphology induced by microfluidization wherein spherical curcumin particles were found dissolved in gum matrix with effective size of 272 nm. Total soluble solids (TSS) of microfluidized suspension increased with increment in number of passes with highest TSS of 1.34 and 1.36 degrees Bx at 100 & 200 MPa, respectively after 12 processing passes. Differential scanning calorimetry revealed melting point of control and microfluidized samples in the range of 118.6-124.7 degrees C. Rheology of microfluidized GC suspensions indicated a pseudoplastic (shear thinning) behavior under applied stress. Results suggest that microfluidization can be used to produce sub-micron size tragacanth gum based curcumin suspension for potential application as curcumin delivery system in functional foods and nutraceuticals.
NSTL
Elsevier