Food Chemistry & Technologyhttp://hdl.handle.net/11019/72024-03-14T22:27:50Z2024-03-14T22:27:50ZApplication of Flow Cytometry to the Detection of Pathogenic BacteriaKennedy, DeirdreWilkinson, Martin G.http://hdl.handle.net/11019/36842024-03-01T07:41:38Z2015-01-01T00:00:00ZApplication of Flow Cytometry to the Detection of Pathogenic Bacteria
Kennedy, Deirdre; Wilkinson, Martin G.
Outbreaks of infections have emphasized the
necessity for rapid and economic detection methods
for pathogens in samples ranging from those of
clinical origin to food products during production and
retail storage, and increasingly, in environmental
samples. Flow cytometry (FCM) allows the rapid
acquisition of multi-parametric data regarding cell
populations within fluidised samples. However, the
application of FCM to pathogen detection depends
on the availability of specific fluorescent probes
such as antibodies and RNA probes capable of
detecting and isolating pathogens from these
diverse samples. A particular issue for FCM
methodology is the ability to recover and
discriminate bacteria from the sample matrix which
may pose a major technical hurdle towards accurate
and sensitive analysis. This review article focuses
on detection of pathogens using FCM in samples
originating from food, water, environmental and
clinical sources and outlines the current state of the
art and potential future applications.
peer-reviewed
2015-01-01T00:00:00ZCharacterisation of the Wetting Behaviour of Poor Wetting Food Powders and the Influence of Temperature and Film FormationFitzpatrick, John J.Salmon, JustineJi, JunfuMiao, Songhttp://hdl.handle.net/11019/36772024-03-01T07:40:57Z2017-01-01T00:00:00ZCharacterisation of the Wetting Behaviour of Poor Wetting Food Powders and the Influence of Temperature and Film Formation
Fitzpatrick, John J.; Salmon, Justine; Ji, Junfu; Miao, Song
Characterisation of the wettability of five poor wetting food powders was performed using static immersion and
contact angle measurements. The effect of temperature (20, 50 and 70 °C) on wettability showed varying effects
on the powders. Higher temperatures majorly improved the wettability of chocolate and high fat powders but
worsened the wettability of sodium caseinate and milk protein isolate. Rate-limiting regime testing was
performed by pouring a fixed mass of powder on to the surface of water in an agitated beaker and visually
assessing what was rate-limiting rehydration after 1 minute. The rate limiting regime tended to be floating at
lower agitation speeds and dispersed clumps of varying sizes at higher speeds. However, there were major
differences observed between the powders. Some of the powders formed strong films at powder/water interfaces,
that could act as a barrier to water penetration and wettability. Consequently, force displacement testing was
performed on a layer of powder on the water surface to assess the strength of any powder film formed. Some of
the powders formed strong films that may in-part explain their poor wetting behaviour and their propensity to
form strong clumps that were difficult to disrupt.
peer-reviewed
2017-01-01T00:00:00ZPreparation and Characterization of Nanoparticles Made from Co-Incubation of SOD and GlucoseCai, LipingLin, ChuntongYang, NannanHuang, ZhijieMiao, SongChen, XiaochaoPan, JianruRao, PingfanLiu, Shutaohttp://hdl.handle.net/11019/36692024-03-03T04:19:40Z2017-12-19T00:00:00ZPreparation and Characterization of Nanoparticles Made from Co-Incubation of SOD and Glucose
Cai, Liping; Lin, Chuntong; Yang, Nannan; Huang, Zhijie; Miao, Song; Chen, Xiaochao; Pan, Jianru; Rao, Pingfan; Liu, Shutao
The attractive potential of natural superoxide dismutase (SOD) in the fields of medicine and functional food is limited by its short half-life in circulation and poor permeability across the cell membrane. The nanoparticle form of SOD might overcome these limitations. However, most preparative methods have disadvantages, such as complicated operation, a variety of reagents-some of them even highly toxic-and low encapsulation efficiency or low release rate. The aim of this study is to present a simple and green approach for the preparation of SOD nanoparticles (NPs) by means of co-incubation of Cu/Zn SOD with glucose. This method was designed to prepare nanoscale aggregates based on the possible inhibitory effect of Maillard reaction on heating-induced aggregation during the co-incubation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results indicated that the Maillard reaction occurred during the co-incubation process. It was found that enzymatically active NPs of Cu/Zn SOD were simultaneously generated during the reaction, with an average particle size of 175.86 ± 0.71 nm, and a Zeta potential of -17.27 ± 0.59 mV, as established by the measurement of enzymatic activity, observations using field emission scanning electron microscope, and analysis of dynamic light scattering, respectively. The preparative conditions for the SOD NPs were optimized by response surface design to increase SOD activity 20.43 fold. These SOD NPs showed storage stability for 25 days and better cell uptake efficacy than natural SOD. Therefore, these NPs of SOD are expected to be a potential drug candidate or functional food factor. To our knowledge, this is the first report on the preparation of nanoparticles possessing the bioactivity of the graft component protein, using the simple and green approach of co-incubation with glucose, which occurs frequently in the food industry during thermal processing.
peer-reviewed
2017-12-19T00:00:00ZPreliminary characterization of a novel β-agarase from Thalassospira profundimonasZeng, ChengZhang, LongtaoMiao, SongZhang, YiZeng, ShaoxiaoZheng, Baodonghttp://hdl.handle.net/11019/36622024-03-03T04:24:19Z2016-07-15T00:00:00ZPreliminary characterization of a novel β-agarase from Thalassospira profundimonas
Zeng, Cheng; Zhang, Longtao; Miao, Song; Zhang, Yi; Zeng, Shaoxiao; Zheng, Baodong
Background
The objective of this study was to characterize the agarase from a newly isolated agarolytic bacterium Thalassospira profundimaris fst-13007.
Results
Agarase-fst was purified to homogeneity which apparent molecular weight was 66.2 kDa. Its activity was optimal at 45 °C and pH 8 and was stable at pH 5–9 or 30–50 °C. Agarase-fst required Mn2+ for agarase activity and inhibition by Cu2+, Fe3+ and EDTA. Tests of hydrolysis pattern and substrate specificity, TLC analysis and mass spectrometry of the hydrolysis products revealed that it is an endo-type β-agarase hydrolyzing agarose into neoagarobiose, neoagarotetraose and neoagarohexaose. Results of MALDI-TOF-TOF/MS indicate that it lack of homology to previously identified proteins and present conserved domain of β-agarase.
Conclusion
Agarase-fst from T. profundimaris fst-13007 was confirmed to be a novel endo-type β-agarase.
peer-reviewed
2016-07-15T00:00:00Z