Effects Of Storage Factors On Accumulation Of Ipomeamarone In Postharvest Sweetpotato Roots

Sweet potato infected by pathogenic fungi,especially ceratocystis fimbriate,will produce furanterpenoid toxins,mainly ipomeamarone,which is harmful to humans and animals.Ipomeamarone is stable,thermostability and not easy to damage.At present,there are few studies on the formation and accumulation of ipomeamarone in sweet potato at home and abroad.Sweet potato as a popular food,ensure its safety on table is necessary.Therefore,developed the research of storage condition on the formation and accumulation conditions of ipomeamarone in sweet potato and established a fast and efficient detection method of ipomeamarone content is essential.This study first used the method of column chromatography conjunction with high performance liquid chromatography obtained ipomeamarone after solation and purification,and then studied the effects of temperature and pathogen on the accumulation and production of ipomeamarone in sweet potato respectively.What's more,the content of ipomeamarone was detected by electronic nose combined with high performance liquid chromatograph.And the following conclusions were obtained.In order to evaluate the effect of storage temperature on ipomeamarone accumulation,three temperature gradients(4?,8?,and 12?)were designed.And the results shown,the cold injury was caused in low-temperature storage sweet potato with an increased MDA content,chilling injury index and electrical conductivity.What's more,the lower storage temperature,the higher content of ipomeamarone accumulated.In this test,the accumulation of ipomeamarone at 4? was highest with a content of 50.65 ?g/g in the 28 th of storage,8? lower(33.77 ?g/g),and 13?lowest(10.05 ?g/g).The rhizopus stolonifer infection test was conducted.And the results shown,the rhizopus stolonifer infection could induced the production of ipomeamarone in sweet potato.With the extension of infected time,the degree of decay of sweet potato tissue deepened,and the content of ipomeamarone increased continuously.In the 28 th of rhizopus stolonifer infection test,the content of ipomeamarone in the sweet potato tissue was reached 93.24 ?g/g.By analyzed with electronic nose and high performance liquid chromatography,the connection of the response strength of electronic nose sensor and the level of ipomeamarone was found.Several sensors,including W2 W,W1W,W5 S were sensitive to the change ofipomeamarone content.With the deepening of the decay,the response value of the electronic nose sensor changed obviously.And the response value of the electronic nose sensor was significantly related to the ipomeamarone content detected by high performance liquid chromatography.When the content of ipomeamarone increased greatly.the electronic nose response value was also increased significantly.To conclude,both storage temperature and rhizopus stolonifer infection could induced the production and accumulation of ipomeamarone in sweet potatoes,and the relative content can be obtained by the response value of the electronic nose.