Conventional methods of DNA recovery from agarose gel generally require expensive equipment, extended elution times, or considerable handling of the sample after elution. We developed a simple protocol for a quick and...Conventional methods of DNA recovery from agarose gel generally require expensive equipment, extended elution times, or considerable handling of the sample after elution. We developed a simple protocol for a quick and effective recovery of DNA from agarose gels with good yield and quality. Using a Sephadex resin filled spin column, DNA fragments of 500 bp to 6 kb in an agarose gel slice were easily recovered by a 2 min centrifugation. The recovery efficiencies were over 40% -50% and the eluted DNA can be used directly for downstream application, such as polymerase chain reactions （PCR） and restriction enzyme digestion. This method could also be used to recover large DNA fragment （48 kb） without degradation. The use of Sephadex helps to remove small molecular impurities from agarose and it also reduces the chance of clogging the column filter caused by direct contact with agarose.展开更多
Heat treatment of milk may cause whey proteins and caseins to form aggregates. These soluble and micellar aggregates and their other properties (size, composition, shape, etc.) can affect the techno-functionalities to...Heat treatment of milk may cause whey proteins and caseins to form aggregates. These soluble and micellar aggregates and their other properties (size, composition, shape, etc.) can affect the techno-functionalities to the milk, conferring interesting or negative features depending on the application in dairy industries. In this study, we propose a new approach to characterise those protein aggregates. SDS-agarose electrophoresis is followed by the calculation of a retention factor (Rf) for each protein spot. Rf allows milk aggregates to be compared qualitatively under the same conditions. This method could be transposed to the dairy industry for a better knowledge of the milk subsequent to heat treatment.展开更多
Using agarose as a gel agent to prepare ceramics is a suitable non-toxic gel-casting method. The effects of agarose concentration and addition amount on gel-cast 3Y-ZrO2 green and sintered bodies were investigated. Gr...Using agarose as a gel agent to prepare ceramics is a suitable non-toxic gel-casting method. The effects of agarose concentration and addition amount on gel-cast 3Y-ZrO2 green and sintered bodies were investigated. Green bodies were prepared by gel-casting using an agarose solution of a different agarose mass fraction including 3.0%, 3.5%, 4.0%, 4.5%, 5.0% and 5.5% with an added amount of agarose in the green body at a mass fraction of 0.7%, and using the agarose solution of a mass fraction of 4.5% with a different amount of added agarose including 0.6%, 0.7%, 0.8%, 0.9%, and 1.0% in terms of mass fraction. The green bodies were sintered at I 600 ~C for 4 h. The relative density, linear shrinkage, and bending strength of the green bodies, and L^e density, microstructure, bending strength, and fracture toughness of sintered samples were characterized and analyzed. Results show that comprehensive properties of green bodies made with 4.5% （in terms of mass fraction） agarose solution added to an mass fraction of agarose in the slurry at 0.6% were the best, of which the bending strength was 3.14 MPa, the linear shrinkage was below 4.3%, and the relative density is 57.3%. For sintered bodies, the best fracture toughness was 5.63 MPa m1/2, and the optimal density was 5.88 gcm-3.展开更多
Agarose gel electrophoresis was performed to study interaction effect of caffeine on photosensitive injury of DNA caused by anthraquinone-2-sulphonic acid disodium(AQS),a model compound of strong photosensitizer,under...Agarose gel electrophoresis was performed to study interaction effect of caffeine on photosensitive injury of DNA caused by anthraquinone-2-sulphonic acid disodium(AQS),a model compound of strong photosensitizer,under 254 nm or 365nm UV irradiation Photosensitive injury of DNA induced by AQS under deoxidized condition was used as control.The results show that caffeine may resist effectively the injury effect of photosensitive damage and strong UV irradiation on DNA.The effects depend on the caffeine and AQS concentration,and irradiation time.Caffeine in concentration of 0.01-3.0μg/μL,may prevent DNA from damage induced by UV light,but caffeine in concentration of>5.0μg/μL accelerates the DNA damage.In particular,in the aqueous solution system of DNA,caffeine and AQS,at pH 6.25-7.35,the caffeine in concentration of 2.5-4.50μg/μL may resist the photosensitive injury of DNA caused by AQS under the deoxidized condition and exposure by 254 nm UV for 10 min.And caffeine in concentration of 5μg/μL would present a synergetic effect on the photosensitive injury of DNA.Possible molecular mechanism also is discussed.展开更多
文摘Conventional methods of DNA recovery from agarose gel generally require expensive equipment, extended elution times, or considerable handling of the sample after elution. We developed a simple protocol for a quick and effective recovery of DNA from agarose gels with good yield and quality. Using a Sephadex resin filled spin column, DNA fragments of 500 bp to 6 kb in an agarose gel slice were easily recovered by a 2 min centrifugation. The recovery efficiencies were over 40% -50% and the eluted DNA can be used directly for downstream application, such as polymerase chain reactions （PCR） and restriction enzyme digestion. This method could also be used to recover large DNA fragment （48 kb） without degradation. The use of Sephadex helps to remove small molecular impurities from agarose and it also reduces the chance of clogging the column filter caused by direct contact with agarose.
文摘Heat treatment of milk may cause whey proteins and caseins to form aggregates. These soluble and micellar aggregates and their other properties (size, composition, shape, etc.) can affect the techno-functionalities to the milk, conferring interesting or negative features depending on the application in dairy industries. In this study, we propose a new approach to characterise those protein aggregates. SDS-agarose electrophoresis is followed by the calculation of a retention factor (Rf) for each protein spot. Rf allows milk aggregates to be compared qualitatively under the same conditions. This method could be transposed to the dairy industry for a better knowledge of the milk subsequent to heat treatment.
基金Funded by the Science&Technology Pillar Program of Hubei Province(No.2015BAA105)the Natural Science Foundation of Hubei Province(No.2014CFB796)
文摘Using agarose as a gel agent to prepare ceramics is a suitable non-toxic gel-casting method. The effects of agarose concentration and addition amount on gel-cast 3Y-ZrO2 green and sintered bodies were investigated. Green bodies were prepared by gel-casting using an agarose solution of a different agarose mass fraction including 3.0%, 3.5%, 4.0%, 4.5%, 5.0% and 5.5% with an added amount of agarose in the green body at a mass fraction of 0.7%, and using the agarose solution of a mass fraction of 4.5% with a different amount of added agarose including 0.6%, 0.7%, 0.8%, 0.9%, and 1.0% in terms of mass fraction. The green bodies were sintered at I 600 ~C for 4 h. The relative density, linear shrinkage, and bending strength of the green bodies, and L^e density, microstructure, bending strength, and fracture toughness of sintered samples were characterized and analyzed. Results show that comprehensive properties of green bodies made with 4.5% （in terms of mass fraction） agarose solution added to an mass fraction of agarose in the slurry at 0.6% were the best, of which the bending strength was 3.14 MPa, the linear shrinkage was below 4.3%, and the relative density is 57.3%. For sintered bodies, the best fracture toughness was 5.63 MPa m1/2, and the optimal density was 5.88 gcm-3.
基金Supported by Natural Science Foundation of Fujian Province,China (2009J01032)Education Committee of Fujian Province,China (JA081336)Specialized Foundation for Creative Team of Young and Middle-aged Teachers of Jimei University (2006A003)
文摘Agarose gel electrophoresis was performed to study interaction effect of caffeine on photosensitive injury of DNA caused by anthraquinone-2-sulphonic acid disodium(AQS),a model compound of strong photosensitizer,under 254 nm or 365nm UV irradiation Photosensitive injury of DNA induced by AQS under deoxidized condition was used as control.The results show that caffeine may resist effectively the injury effect of photosensitive damage and strong UV irradiation on DNA.The effects depend on the caffeine and AQS concentration,and irradiation time.Caffeine in concentration of 0.01-3.0μg/μL,may prevent DNA from damage induced by UV light,but caffeine in concentration of>5.0μg/μL accelerates the DNA damage.In particular,in the aqueous solution system of DNA,caffeine and AQS,at pH 6.25-7.35,the caffeine in concentration of 2.5-4.50μg/μL may resist the photosensitive injury of DNA caused by AQS under the deoxidized condition and exposure by 254 nm UV for 10 min.And caffeine in concentration of 5μg/μL would present a synergetic effect on the photosensitive injury of DNA.Possible molecular mechanism also is discussed.
