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nnel system, labor system and the system of distribution, the state - owned enterprises begin to attach importance to the manpower management. The manpower resources have become the key competitive resources of enterprise. The thesis sets forth how to establish the concept of manpower foun  相似文献   

3.
Abstract: Campylobacter spp. is recognized as one of the most common cause of food‐borne bacterial gastroenteritis in humans. Campylobacter infection causes campylobacteriosis, which can range from asymptomatic to dysentery‐type illnesses with severe complications, such as Guillian‐Barre syndrome. Epidemiological studies have revealed that consumption of poultry products is an important risk factor of this disease. Adherence and cytotoxic activity of the bacteria to host mucosal surfaces have been proposed to be critical steps in pathogenesis. Innovative tools for controlling Campylobacter, such as natural products from plants, represent good alternatives for use in foods or as therapeutic agents. In this study, 28 edible or medicinal plants species were analyzed for their bactericidal effects on the growth of Campylobacter jejuni and C. coli. The extracts of Acacia farnesiana, Artemisia ludoviciana, Opuntia ficus‐indica, and Cynara scolymus were the most effective against these microorganisms at minimal bactericidal concentrations (MBCs) of 0.3, 0.5, 0.4, and 2.0 mg/mL, respectively. No effect on growth was detected with lower concentrations of extract (25%, 50%, or 75% of the MBC) added to the media. The effect of each extract (75% of the MBC) on adherence and cytotoxicity of C. jejuni and C. coli was evaluated in Vero cells. Adherence of Campylobacter to Vero cells was significantly affected by all the extracts. Cytotoxic activity of bacterial cultures was inhibited by A. farnesiana and A. ludoviciana. These plant extracts are potential candidates to be studied for controlling Campylobacter contamination in foods and the diseases associated with this microorganism. Practical Application: Innovative tools for controlling Campylobacter, such as natural products from plants, represent good alternatives for use in foods or as therapeutic agents. The extracts of Acacia farnesiana, Artemisia ludoviciana, Opuntia ficus‐indica, and Cynara scolymus were the most effective against these microorganisms. Adherence and cytotoxic activity of the bacteria to host mucosal surfaces which are critical steps in pathogenesis were decreased by these extracts. Our results point to these plants as potential candidates for the control of Campylobacter contamination in foods, the treatment of the diseases associated with this microorganism, and as feed supplements to reduce on‐farm prevalence of Campylobacter.  相似文献   

4.
Phenylpropanoid amides of octopamine (OA) 1a1e and dopamine (DA) 2a2e were synthesised and the structure–activity relationships (SARs) for antioxidant and tyrosinase inhibition activities were analysed. Among synthesised compounds, 2c, which contains two catechol moieties, exhibited the most DPPH radical-scavenging activity (EC50 = 16.2 ± 2.4 μM), and 1d exhibited significant tyrosinase inhibitory activity (IC50 = 5.3 ± 1.8 μM). Interestingly, with the same acid moiety, OA derivatives showed more inhibitory effect on tyrosinase than did compounds derived from DA, whereas DA derivatives were found to have higher antioxidant activity than compounds derived from OA. The relationship between their structures and their potencies, demonstrated in the current study, will be useful for the design of optimal agents.  相似文献   

5.
Water-extractable hemicellulose (WEH) fractions, containing approximately 65% arabinoxylans (WE-AX) and 20% mixed-linkage β-glucans were isolated from rye bran. In addition, water-extractable mixed-linkage β-glucans (BG) were isolated from oat bran as a reference material. The β-glucan content of the rye hemicellulose isolate was reduced to less than 5% by a selective lichenase treatment. Rye hemicelluloses, WEH and WE-AX had arabinose-to-xylose ratios of 0.54 and 0.57 and weight-average molecular weights (Mw) of 270 000 and 232 000 g/mol respectively. The Mw of BG was higher at 386 000 g/mol. The material properties of films prepared from the rye hemicellulose isolate and WE-AX as such, or with varying amounts of added BG (20:80; 50:50; 80:20 ratios) were studied. Prior removal of β-glucan from the isolate decreased the tensile strength of the films significantly as well as the elongation at break. Addition of BG to the purified WE-AX resulted in an increase in the tensile strength and elongation at break of the films. In contrast, the presence of BG had no clear effect on the oxygen permeability of the films. Both pure rye WE-AX and pure BG films showed excellent oxygen barrier properties (between 0.9 and 1.0 cm3 μm/m2 d kPa). However, the water vapor permeability increased with addition of increasing amounts of BG to WE-AX. To our knowledge, this is the first study on the effect of β-glucans on the material and permeability properties of arabinoxylan-based films.  相似文献   

6.
Limited enzymatic hydrolysis trials of WPC-80 and β-lactoglobulin AA, AB and BB were performed using specific enzymes (trypsin, Neutrase, Corolase PP, Corolase PS) in a pH-stat under controlled conditions. The hydrolysates of WPC-80 and β-lactoglobulin were fractionated into high and low molecular fractions. Residual antibody binding activity of the peptides was dependent on the degree of hydrolysis (DH 2-20), but also on the enzyme used. Heat treatment affected the solubility and thereby the antigenic response. Dialysis influenced the antibody binding activity of the peptides. Tryptic hydrolysis of β-lactoglobulin AA was slower than for β-lactoglobulin BB and AB. Antigenic responses of the hydrolysates and fractions were measured by SLOT-BLOT and ELISA. SLOT-BLOT, a rapid screening method, was not able to differentiate the hydrolysates. The ELISA, being a more sensitive method, differentiated between the genetic variants, but was more time consuming. The lowest antigenicity was observed in the 1000–5000 Da fraction and β-lactoglobulin AA showed the lowest response.  相似文献   

7.
The effects of hyper-oxygenation and storage period of Macabeo and Airén white wines on color characteristics, phenolic, and volatile composition have been evaluated. Hyper-oxygenation treatment provoked a significant decrease in virtually all individual phenolic compounds in must, young wine, and one-year-aged wines, above all hydroxycinnamic acid derivatives, flavonols, and the new GRP derivatives compounds (derived from 2-S-glutathionyl-caftaric acid or grape reaction product). Despite this fact, the contribution of the yellow color component (b*) of white wines derived from hyper-oxygenated musts was significantly higher in comparison with untreated ones, even after 1 year of bottle storage. On the other hand, the concentration of major volatile compounds and some alcohols (namely, C6 alcohols, terpenes, and lactones) was higher in wines derived from hyper-oxygenated musts, but the hyper-oxygenation effect on volatile profile deeply depended on the grape variety. After 1 year of bottle storage, the significant differences were maintained and the content of some long-chain esters increased as a consequence of oxygen addition.  相似文献   

8.
Leno and lace are two kinds of special fabrics respectively born in the East and the West. Although the origin and weaving method of the fabrics are different, they have many similarities and occupy an important position in the history of textile. Based on the historical documents analysis, one can find that the origin of both fabrics is related to mesh-shaped capture tools and their appearance is featured by perforated appearance. With the aesthetic style of elegance, elaboration and grace, both fabrics symbolize noble identity in the upper class. The aesthetic orientation of leno and lace are usually related to the female, and they are the media for the female to hide or express their right and desire. So, the paper expatiates on cultural connotation of leno and lace from their origin, aesthetic tendency and the female spirit they represent. © 2017 China Silk Association. All rights reserved.  相似文献   

9.
Kiro Mojsov 《纺织学会志》2013,104(7):905-911
Bio-processing was accompanied by a significant lower demand of energy, water, chemicals, time and costs. This study attempted to introduce the bio-processes in the conventional scouring and bleaching with peracetic acid (PAA) of the cotton fabrics. The scouring with two types of pectinases, acting under acidic and alkaline conditions, respectively, was as efficient as the chemical process in terms of obtained adequate water absorbency of the fabrics. Bleaching with PAA can substitute bleaching with hydrogen peroxide when medium degree of whiteness is demanded. The bioscouring and bleaching with PAA processes cause no damage to fibres and this is one of the benefits of such processes. Wastewaters are not charged with harmful chemicals. The consumption of water and energy is the lowest at combined scouring/bleaching treatments. Consequently, at these processes arises the lowest amount of effluents and the produced wastewater is biodegradable.  相似文献   

10.
α-Lactalbumin (α-LA) and β-lactoglobulin (β-LG) were isolated from yak milk and identified by mass spectrometry. The variant of α-LA (L8IIC8) in yak milk had 123 amino acids, and the sequence differed from α-LA from bovine milk. The amino acid at site 71 was Asn (N) in domestic yak milk, but Asp (D) in bovine and wild yak milk sequences. Yak β-LG had 2 variants, β-LG A (P02754) and β-LG E (L8J1Z0). Both domestic yak and wild yak milk contained β-LG E, but it was absent in bovine milk. The amino acid at site 158 of β-Lg E was Gly (G) in yak but Glu (E) in bovine. The yak α-LA and β-LG secondary structures were slightly different from those in bovine milk. The denaturation temperatures of yak α-LA and β-LG were 52.1°C and 80.9°C, respectively. This study provides insights relevant to food functionality, food safety control, and the biological properties of yak milk products.  相似文献   

11.
The study was designed to investigate the effects of nutritional level (control diet (CD), 14.19% crude protein, 13.81 MJ of DE/kg; low nutritional level diet (LND), 11.08% crude protein, 12.55 MJ of DE/kg) on pork quality and gene expression of μ-calpain and calpastatin in muscle of finishing pigs. The LND treatment increased drip loss (P < 0.05), had a trend to increase intramuscular fat (IMF) content (P = 0.09), decreased Warner–Bratzler shear force (WBSF) of pork (P < 0.05), improved mRNA level of μ-calpain (P < 0.05) in skeletal muscle, but had no effect on gene expression of calpastatin, compared with the CD treatment. These data suggest that a moderately reduced energy and protein diet increased pork tenderness and intramuscular fat. The increase in tenderness by LND treatment may be partly due to increased gene expression of μ-calpain in muscle.  相似文献   

12.
Total antioxidant activity, levels of bio-active compound groups and instrumental colour of tomato and carrot purée subjected to high pressure treatment (400–600 MPa/15 min/20 °C) and thermal treatments (70 °C/2 min) were measured. Antioxidant activity in tomato and carrot purée was significantly higher (p < 0.05) than in untreated or thermally processed samples. High pressure treatments at 600 MPa retained more than 90% of ascorbic acid as compared to thermal processing in tomato purées. Heat treatments caused a rapid decrease in ascorbic acid (p < 0.05). Phenolic contents were in general un-affected by thermal or high pressure treatments. Colour parameters were significantly affected (p < 0.05) by thermal and high pressure processing. Principal component analysis (PCA) revealed that the first two components represented 97% and 92% of the total variability in instrumental colour parameters with respect to processing for tomatoes and carrots respectively.Industrial relevanceThis research paper provides scientific evidence of the potential benefits of high pressure processing in comparison to thermal treatments in retaining important bioactive compounds. Antioxidant activity (ARP), ascorbic acid, and carotenoids after exposure to high pressure treatments (400–600 MPa) were well retained. Our results also show that redness and colour intensity of purées were better preserved by high pressure processing than conventional thermal treatment. It would appear from a nutritional prospective, high pressure processing is an excellent food processing technology which has the potential to retain compounds with health properties in foods. Therefore high pressure processed foods could be sold at a premium over their thermally processed counterparts as they will have retained their fresh-like properties.  相似文献   

13.
Lee Y  Choe E 《Journal of food science》2011,76(3):C498-C503
Abstract: Interaction of phosphatidylcholine (PC) and α‐tocopherol (α‐Toc) on the oxidation of oil in the emulsion consisting of sunflower oil and water under singlet oxygen at 25 °C was studied by determining peroxide value (PV) and conjugated dienoic acid (CDA) contents. Singlet oxygen was produced by chlorophyll b under 1700 lux. Single addition of PC or α‐Toc decreased the values of peroxides and CDAs of oil in the emulsion via singlet oxygen quenching. PC and α‐Toc showed simply additive interaction in decreasing the singlet oxygen oxidation of oil in the emulsion. α‐Toc was a physical quencher of singlet oxygen in the emulsion, but PC involved chemical quenching in the antioxidant action. Chlorophyll and PC contents were decreased in the emulsion under singlet oxygen, while α‐Toc was not. α‐Toc protected chlorophyll and PC from degradation, and was a more important component than PC in the oil oxidation under singlet oxygen in the emulsion.  相似文献   

14.
Gelation of sodium κ-carrageenan (KC) in the presence of sodium caseinate (SC) was investigated by oscillating shear rheology. The effect of adding NaCl and KCl was investigated. Temperature ramps showed that SC had no influence on the critical gelation temperature, but increased the melting temperature when that of the pure gels was less than about 30 °C. The presence of SC also increased the gel strength of weak KC gels. Light scattering and confocal laser scanning microscopy showed that the proteins associated with the KC network. The rheology of the gels indicated that the mixed gels contained bonds involving both SC and KC in addition to pure KC bonds. At relatively high SC content the former type of bonds dominated.  相似文献   

15.
Technical hexachlorocyclohexane (HCH) was one of the most widely used pesticides during the 20th century. Although production and use were phased-out during the 1990s, two of its major components, α- and β-HCH, are still ubiquitous in the environment. Here, we have collected and analyzed data on concentrations of α- and β-HCH in the atmosphere and oceans, including spatial and temporal trends and seasonalities. We apply a global fate and transport model to both isomers over the period 1950 to 2050 to rationalize current levels and trends at remote locations with estimated emissions and to forecast into the near future. Our model results indicate that secondary emissions from soils and oceans are currently controlling the observed rates of decline in the atmosphere. β-HCH is declining more slowly than α-HCH due to its higher persistence, and we hypothesize that it will eventually become the predominant isomer of HCH in the environment. The model reproduces over 70% of measured concentrations of α-HCH in air and ocean water within factors of 3 and 5, respectively, and over 70% of measured concentrations of β-HCH within factors of 8 and 20, respectively. The model results are only weakly sensitive to climate change-induced trends in Arctic sea-ice cover and temperature.  相似文献   

16.
Bread represents a suitable food product for the addition of functional ingredients, such as the cholesterol-lowering dietary fibre oat β-glucan and the prebiotic inulin. Therefore, these soluble fibres were incorporated into wheat as well as gluten-free bread, and their effects on rheological properties of the dough, on bread quality and on crumb microstructure were compared. The level of remaining β-glucan as well as its molecular weight was determined using an enzyme kit and size-exclusion chromatography. The addition of oat β-glucan resulted in a higher water addition level, whereas incorporation of inulin had the opposite effect. Rheological testing showed that the incorporation of oat β-glucan results in a more elastic dough. The baking characteristics mainly affected by fibre addition were volume and crust colour, with inulin increasing and oat β-glucan decreasing loaf-specific volume in the gluten-free breads. Inulin led to a darkening of the crust of both bread types, whereas addition of oat β-glucan resulted in a lighter crust of gluten-free bread. Oat β-glucan softened the crumb of gluten-free bread, but had the opposite effect on wheat bread. Inulin resulted in an increased crumb hardness as well as the rate of staling. Beta-glucan breakdown was more pronounced in wheat bread than in gluten-free bread. The results show that the use of β-glucan to increase the nutritional value of wheat bread is limited due to negative influences on technological properties. However, this soluble fibre is highly suitable for incorporation into gluten-free bread.  相似文献   

17.
Heterogeneous photocatalytic reduction of As(V) and As(III) at different concentrations over TiO(2) under UV light in deoxygenated aqueous suspensions is described. For the first time, As(0) was unambiguously identified together with arsine (AsH(3)) as reaction products. As(V) reduction requires the presence of an electron donor (methanol in the present case) and takes place through the hydroxymethyl radical formed from methanol oxidation by holes or hydroxyl radicals. On the contrary, As(III) reduction takes place through direct reduction by the TiO(2)-conduction band electrons. Detailed mechanisms for the photocatalytic processes are proposed. Although reduction to solid As(0) is convenient for purposes of As removal from water as a deposit on TiO(2), attention must be paid to formation of AsH(3), one of the most toxic forms of As, and strategies for AsH(3) treatment should be considered.  相似文献   

18.
β-lactoglobulin (β-lg) is one of the most widely used proteins in food industry. Purification of β-lg from buffalo milk while maintaining its native structure is of practical influence to the industry. This research demonstrated that β-lg can be separated efficiently from whey using 70 g kg??1 NaCl at pH 2.0, which showed higher yield and activity of β-lg. It was found that the presence of NaCl or the changing of pH had no influence on the secondary structure of β-lg while they significant influenced the tertiary structure of β-lg. More hydrophobic groups were exposed with increasing NaCl concentration. Presence of low concentration of NaCl inhibited the exposure of Trp while the exposure of Trp was increased in the presence of high concentration of NaCl. In contrast, pH changes did not influence the exposure of Trp while the decrease of pH in the range of 7.5–5.5 decreased the exposure of hydrophobic groups to the hydrophilic environment.  相似文献   

19.
The use of antioxidant-rich medicinal plants having the potential to reduce oxidative stress and postprandial hyperglycemic pressure is one of the most promising option for the management of diabetes. This study presents information on metabolite profiling and in vitro anti-diabetic effects of leaf extracts of Ficus benjamina. The DPPH (2, 2-diphenyl-1-picrylhydrazyl radicals) assay was performed to determine the in vitro antioxidant potential of the plant extracts. The anti-diabetic effects were investigated by evaluating inhibitory properties of F. benjamina leaf extracts towards carbohydrate hydrolyzing enzymes, i.e., α-glucosidase and α-amylase, whereas 1H NMR and UHPLC-QTOF-MS/MS analytical methods were employed for metabolite profiling of F. benjamina leaf extracts. Among 40, 60, 80, and 100% ethanolic leaf extracts of F. benjamina, 80% ethanolic extract exhibited the highest antioxidant activity based upon its DPPH radical scavenging ability (IC50 value: 63.71 ± 2.66 µg/mL). The 80% ethanolic leaf extract of F. benjamina also proved to be the most efficient α-glucosidase and α-amylase inhibitor with IC50 values of 9.65 ± 1.04 µg/mL and 13.08 ± 1.06 µg/mL, respectively; these values were even better than acarbose with α-glucosidase inhibition activity (IC50 = 116.01 ± 3.83 µg/mL) and α-amylase inhibition activity (IC50 = 152.66 ± 7.32 µg/mL). Moreover, a total of 31 metabolites were identified in F. benjamina leaf extract, which may have the potential to contribute to its antioxidant and inhibitory properties against carbohydrate hydrolyzing enzymes. The findings of this study depict F. benjamina leaf extracts as a promising α-glucosidase and α-amylase inhibitor, and therefore, can be utilized for the development of anti-diabetic functional diets/nutra-pharmaceuticals.  相似文献   

20.
The interest in the development of edible and biodegradable films has increased because it is every day more evident that non-degradable materials are doing much damage to the environment. In this research, bioplastics were based on blends of manioc starch (native and modified) and gelatin in different proportions, added of glycerol or sorbitol, which were used as plasticizers. The objective was to study the effect of two different plasticizers, glycerol and sorbitol, and different concentrations of starch and gelatin on the barrier (water vapor permeability – WVP), mechanical (tensile strength and elongation at break), physicochemical (solubility in water and in acid) and physical properties (opacity and thickness) of the obtained bioplastics samples. As a result, all of them showed transparency and resistance to tensile strength, as well as increasing in thickness values and in the WVP, as the gelatin content increased in the formulations. Finally, all results for tensile strength and elongation at break obtained for those samples plasticized with sorbitol were better than those plasticized with glycerol.  相似文献   

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