| Clostridium perfringens is a gram-positive anaerobic bacterium that can produce toxins.It is one of the common zoonotic pathogens and can be life-threatening in severe cases.Disease outbreaks caused by C.perfringens are often associated with vacuum-packaged meat products because they are anaerobic bacteria.C.perfringens can produce spores with strong resistance to stress.Once the sterilization is not thorough,it is easy to germinate,grow,and multiply in large quantities during production,transportation,and sales,leading to bagging,spoilage,and even endangering consumer health.In view of the above harmful characteristics of C.perfringens,this study aims to control it from the following three aspects:（1）To inhibit the growth of C.perfringens at its source,a dual-mode sensing platform using the synergy between fluorescent and electrochemical signals for C.perfringens detection was proposed,and a dual-amplification technology based on DNA walker and hybridization chain reaction（HCR）were introduced to improve detection.When the C.perfringens DNA was present,it specifically bonded with FAM-labeled aptamer led to the release of DNA walker to start the synthesis of double-stranded DNA.HCR occurred subsequently and produced long-chain ds DNA that combined with methylene blue（MB）.The synergistic effects of MB and FAM significantly improved the sensitivity and accuracy of the dual-mode sensor.As a result,the biosensor displayed an excellent analytical performance for C.perfringens at a concentration of 1-108 CFU/g.A minimum concentration of 1 CFU/g and good accuracy was detected in real samples.The proposed ultrasensitive detection method for detecting C.perfringens in food showed great potential in controlling foodborne diseases.（2）During the meat production process,the effects of ginger essential oil（GEO）and grape seed extract（GSE）treatments on germination and growth of C.perfringens spores in chicken after linear cooling and isothermal storage were evaluated.GEO or GSE（1%）can properly inhibit the germination and growth of C.perfringens spores during cooling from 50°C to 4°C.The kinetic models of Gompertz and Rat-kowsky were carried out to describe the spore germination and growth of C.perfringens in GEO-and GSE-treated chickens at 15°C～45°C.Results showed a high degree of fit.The addition of GEO and GSE increased the lag phase at all storage temperatures（λ）,the maximum increase was 47.892 h;decreased the growth rate(Rmax),the maximum reduction was 0.642 lg CFU/h;and extended the shelf-life,the maximum extension was 37.608 h,compared with the control group.The models provided a cost-effective and fast technology for replacing traditional culture methods and evaluating the effect of temperature and plant extracts on the shelf life of meat.（3）During the storage of meat products,the GEO nanoemulsion delivery system was prepared by embedding GEO into emulsifiers for chelating ZH and GSE in this study.Firstly,the particle size of nanoemulsion solution during long-term storage（4 weeks）was measuredζ-Potential changes to evaluate their stability differences.Compared with zh alone,the particle size andζ-The potential did not change significantly,and remained between 230.5～168.9 nm and-33.62～-39.33m V,with good stability.Moreover,the GEO nanoemulsion prepared with a ZH/GSE mass ratio of1:0.3 has the minimum particle size（168.9±5.45 nm）,maximumζ-potential（-39.33 m V）,and the maximum embedding rate（94.69%）,which had the best stability.Spectral analysis showed that ZH and GSE exposed more hydroxyl groups,making nanoemulsions more hydrophilic.GSE could significantly improve the water solubility of nanoemulsions.In addition,GEO nanoemulsions displayed the better bactericidal properties compared with GEO,attribute to the improved solubility of GEO.Therefore,it showed the certain application prospects in the field of control of C.perfringens. |
