The antimicrobial and antioxidant effects of two spice extracts and their combination on raw chicken meat during storage for 15 days at 4◦C were studied.Raw chicken meat was treated with BHT(positive control),rosemary...The antimicrobial and antioxidant effects of two spice extracts and their combination on raw chicken meat during storage for 15 days at 4◦C were studied.Raw chicken meat was treated with BHT(positive control),rosemary(RO),cloves(CL),and their combination,and the results were compared to those obtained for raw chicken meat without any additive(negative control).The antioxidant and antimicrobial activities of spice extracts were determined.The total phenolic and total flavonoid contents of rosemary was lower than those of cloves.Cloves exhibited a higher DPPH radical scavenging activity than that of rosemary.However,the ferrous ion-chelating effect of rosemary was significantly higher than that of cloves.The pH,instrumental colour(CIE L*,a*,b*),total viable counts(TVC),lactic acid bacteria(LAB)counts,Enterobacteriaceae counts,Pseudomonas spp.counts and 2-thiobarbituric acid reactive substances(TBARS)were determined at 3-day intervals over a period of 15 days.The bacterial counts of T-RO-CL samples were lower than those of control samples during storage.T-RO-CL samples maintained significantly(P<0.05)higher L*,a*and b*values during storage.The TBARS values of T-RO-CL samples were the lowest among the samples.These results demonstrate that spice extracts are highly effective against microbial growth and lipid oxidation and show potential as a natural antioxidant in raw chicken meats.展开更多
Hydrothermal reactions of biphenyl-2,3,3A,5A-tetracarboxylic acid（H4bptc） with cobalt salt in the presence of 1,4-bis（2-pyridylmethyl）piperazin（bpmp） afforded one novel coordination polymer, namely, [Co（H2bptc...Hydrothermal reactions of biphenyl-2,3,3A,5A-tetracarboxylic acid（H4bptc） with cobalt salt in the presence of 1,4-bis（2-pyridylmethyl）piperazin（bpmp） afforded one novel coordination polymer, namely, [Co（H2bptc）（bpmp）0.5（H2O）]n（1）. Its structure was established by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra and TG analysis. Complex 1 crystallizes in monoclinic, space group P21/c with a = 11.4839（11）, b = 16.6690（16）, c = 11.5559（11） A, V = 2201.8（4） A3, Mr = 539.35, Dc = 1.627 g/cm^3, μ（MoK α） = 0.841 mm-1, F（000） = 1108, Z = 4, the final R = 0.0309 and w R = 0.0705 for 4090 observed reflections（I 2σ（I））. Complex 1 displays a one-dimensional（1D） chain bridged by bpmp. Two carboxylic groups of H4 bptc ligand adopt μ01-η1：η1 and μ1-η1：η coordination modes to bridge adjacent Co（Ⅱ） ions together with bpmp ligand to give alternately arranged left- and right-handed helical chains. In addition, variable-temperature magnetic susceptibility measurements indicate that complex 1 shows weak antiferromagnetic interactions between the adjacent Co（Ⅱ） ions.展开更多
As a new mutagenetic method, low-energy ion implantation has been used widely in many research areas in recent years. In order to obtain some industrial strains with high xylanase yield, the wild type strain Aspergill...As a new mutagenetic method, low-energy ion implantation has been used widely in many research areas in recent years. In order to obtain some industrial strains with high xylanase yield, the wild type strain Aspergillus niger A3 was mutated by means of nitrogen ions implantation （10 keV, 2.6× 10^14 ～ 1.56 × 10^15 ions/cm^2） and a mutant N212 was isolated subsequently. However, it was found that the initial screening means of the high-yielding xylanase strains such as transparent halos was unfit for first screening. Compared with that of the wild type strain, xylanase production of the mutant N212 was increased from 320 IU/ml to 610 IU/ml, and the optimum fermentation temperature was increased from 28 ℃ to 30 ℃.展开更多
In order to select an optimum extraction method for the target glycoprotein （TGP） from jellyfish （Rhopilema esculentum） oral-arms, a high performance liquid chromatography （HPLC）-assay for the determination of t...In order to select an optimum extraction method for the target glycoprotein （TGP） from jellyfish （Rhopilema esculentum） oral-arms, a high performance liquid chromatography （HPLC）-assay for the determination of the TGP was developed Purified target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted against concentration for TGP were linear （r= 0.9984, y=4.5895x＋47.601） over concentrations ranging from 50 to 400mgL^-1. The mean extraction recovery was 97.84% （CV2.60%）. The fractions containing TGP were isolated from jellyfish （R esculentum） oral-arms by four extraction methods： 1） water extraction （WE）, 2） phosphate buffer solution （PBS） extraction （PE）, 3） ultrasound-assisted water extraction （UA-WE）, 4） ultrasound-assisted P/3S extraction （UA-PE）. The lyophilized extract was dissolved in Milli-Q water and analyzed directly on a short TSK-GEL G4000PWXL （7.8 mm×300 ram） column. Our results indicated that the UA-PE method was the optimum extraction method selected by HPLC.展开更多
To improve the oxidative stability and application of fish oil, it was microencapsulated by simple coacervation followed by spray drying. Simple coacervation took place by adding malt dextrin into the emulsion of fish...To improve the oxidative stability and application of fish oil, it was microencapsulated by simple coacervation followed by spray drying. Simple coacervation took place by adding malt dextrin into the emulsion of fish oil and hydroxypropyl methylcellulose （HPMC） solution. Influences of several process parameters on the microencapsulation were evaluated and the oxidative stability and microstructure of microcapsules were analyzed. Results showed that the coacervation could be observed only when dextrose equivalent value （DE value） of malt dextrin, concentration of HPMC solution and fish oil percentage in microcapsules were no more than 20. 5% and 40%, respectively. Moreover, microencapsulation efficiency was higher at HPMC solution concentration of 4% and fish oil percentage of less than 30%. The oxidative stability of fish oil was improved by the microencapsulation and done best in the ease of replacing malt dextrin by 40% with acacia. Scanning electronic microscopic photographs showed that the microcapsule obtained was a round, smooth and hollow microcapsule with its wall made up of innumerable small and solid submicrocapsules with the core of fish oil.展开更多
文摘The antimicrobial and antioxidant effects of two spice extracts and their combination on raw chicken meat during storage for 15 days at 4◦C were studied.Raw chicken meat was treated with BHT(positive control),rosemary(RO),cloves(CL),and their combination,and the results were compared to those obtained for raw chicken meat without any additive(negative control).The antioxidant and antimicrobial activities of spice extracts were determined.The total phenolic and total flavonoid contents of rosemary was lower than those of cloves.Cloves exhibited a higher DPPH radical scavenging activity than that of rosemary.However,the ferrous ion-chelating effect of rosemary was significantly higher than that of cloves.The pH,instrumental colour(CIE L*,a*,b*),total viable counts(TVC),lactic acid bacteria(LAB)counts,Enterobacteriaceae counts,Pseudomonas spp.counts and 2-thiobarbituric acid reactive substances(TBARS)were determined at 3-day intervals over a period of 15 days.The bacterial counts of T-RO-CL samples were lower than those of control samples during storage.T-RO-CL samples maintained significantly(P<0.05)higher L*,a*and b*values during storage.The TBARS values of T-RO-CL samples were the lowest among the samples.These results demonstrate that spice extracts are highly effective against microbial growth and lipid oxidation and show potential as a natural antioxidant in raw chicken meats.
基金supported by the National Natural Science Foundation of China(No.21273101 and 21302082)the Foundation of the Program for Backbone Teachers in Universities of Henan Province(No.2012GGJS158)
文摘Hydrothermal reactions of biphenyl-2,3,3A,5A-tetracarboxylic acid（H4bptc） with cobalt salt in the presence of 1,4-bis（2-pyridylmethyl）piperazin（bpmp） afforded one novel coordination polymer, namely, [Co（H2bptc）（bpmp）0.5（H2O）]n（1）. Its structure was established by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra and TG analysis. Complex 1 crystallizes in monoclinic, space group P21/c with a = 11.4839（11）, b = 16.6690（16）, c = 11.5559（11） A, V = 2201.8（4） A3, Mr = 539.35, Dc = 1.627 g/cm^3, μ（MoK α） = 0.841 mm-1, F（000） = 1108, Z = 4, the final R = 0.0309 and w R = 0.0705 for 4090 observed reflections（I 2σ（I））. Complex 1 displays a one-dimensional（1D） chain bridged by bpmp. Two carboxylic groups of H4 bptc ligand adopt μ01-η1：η1 and μ1-η1：η coordination modes to bridge adjacent Co（Ⅱ） ions together with bpmp ligand to give alternately arranged left- and right-handed helical chains. In addition, variable-temperature magnetic susceptibility measurements indicate that complex 1 shows weak antiferromagnetic interactions between the adjacent Co（Ⅱ） ions.
基金the National Key Technologies R & D Program of China during the 10th Five-Year Plan(No.2001BA302B)
文摘As a new mutagenetic method, low-energy ion implantation has been used widely in many research areas in recent years. In order to obtain some industrial strains with high xylanase yield, the wild type strain Aspergillus niger A3 was mutated by means of nitrogen ions implantation （10 keV, 2.6× 10^14 ～ 1.56 × 10^15 ions/cm^2） and a mutant N212 was isolated subsequently. However, it was found that the initial screening means of the high-yielding xylanase strains such as transparent halos was unfit for first screening. Compared with that of the wild type strain, xylanase production of the mutant N212 was increased from 320 IU/ml to 610 IU/ml, and the optimum fermentation temperature was increased from 28 ℃ to 30 ℃.
基金support from the National High Technology Research and Development Program of China (No.2006AA09Z438)
文摘In order to select an optimum extraction method for the target glycoprotein （TGP） from jellyfish （Rhopilema esculentum） oral-arms, a high performance liquid chromatography （HPLC）-assay for the determination of the TGP was developed Purified target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted against concentration for TGP were linear （r= 0.9984, y=4.5895x＋47.601） over concentrations ranging from 50 to 400mgL^-1. The mean extraction recovery was 97.84% （CV2.60%）. The fractions containing TGP were isolated from jellyfish （R esculentum） oral-arms by four extraction methods： 1） water extraction （WE）, 2） phosphate buffer solution （PBS） extraction （PE）, 3） ultrasound-assisted water extraction （UA-WE）, 4） ultrasound-assisted P/3S extraction （UA-PE）. The lyophilized extract was dissolved in Milli-Q water and analyzed directly on a short TSK-GEL G4000PWXL （7.8 mm×300 ram） column. Our results indicated that the UA-PE method was the optimum extraction method selected by HPLC.
基金Project supported by the Doctoral Foundation of Guangdong Natural Science Foundation （No. 04300744）.
文摘To improve the oxidative stability and application of fish oil, it was microencapsulated by simple coacervation followed by spray drying. Simple coacervation took place by adding malt dextrin into the emulsion of fish oil and hydroxypropyl methylcellulose （HPMC） solution. Influences of several process parameters on the microencapsulation were evaluated and the oxidative stability and microstructure of microcapsules were analyzed. Results showed that the coacervation could be observed only when dextrose equivalent value （DE value） of malt dextrin, concentration of HPMC solution and fish oil percentage in microcapsules were no more than 20. 5% and 40%, respectively. Moreover, microencapsulation efficiency was higher at HPMC solution concentration of 4% and fish oil percentage of less than 30%. The oxidative stability of fish oil was improved by the microencapsulation and done best in the ease of replacing malt dextrin by 40% with acacia. Scanning electronic microscopic photographs showed that the microcapsule obtained was a round, smooth and hollow microcapsule with its wall made up of innumerable small and solid submicrocapsules with the core of fish oil.
