Effect Of Cooking Methods And Simulating The Gastrointestinal Environment In Vitro On The Content Of Glucoraphanin And Sulforaphane In Broccoli

A large number of studies had shown that the consumption of cruciferous vegetables,such as broccoli,played an important role in cancer prevention and anti-cancer.Further research found that was because the cruciferous plant contained the secondary metabolite glucosinolates.Glucosinolates were hydrolyzed by myrosinase to produce isothiocyanate,thiocyanates,nitriles,epithionitriles and oxazolidine-2-thiones.Sulforaphane was an isothiocyanate and one of the best natural products found to have anticancer activity.Studies had shown that in addition to its anti-cancer function,sulforaphane had also shown good results in preventing cardiovascular diseases,anti-oxidation,anti-inflammatory and antibacterial.As the precursor of sulforaphane,glucoraphanin was the highest content of glucosinolates in broccoli.In this experiment,“Rinong” broccoli was as the material.we studied the change trend of the contents of glucoraphanin and sulforaphane in broccoli with cooking time under four cooking methods(steaming,boiling,stir-frying and microwaving),(2)effects of exogenous myrosinase on the conversion rate of glucoraphanin to sulforaphane,(3)contents change of glucoraphanin and sulforaphane in broccoli under simulated gastrointestinal digestion in vitro,specific results as follows:1.The glucoraphanin retention in steamed broccoli was the highest during the same treatment time;when the treatment time was 4 minutes,the retention amount of glucoraphanin in steaming,boiling,stir-frying and microwaving broccoli were respectively 111.95?g/g,85.40?g/g,58.51?g/g and 79.39 ?g/g?2.The content of sulforaphane in broccoli increased first and then decreased with the prolongation of cooking time.Under the steaming and boiling treatment,the content of sulforaphane reached the highest at 4 minute,the content of sulforaphane was respectively 48.1?g/g and 35.56 ug/g;under the stir-frying and microwaving treatment,the content of sulforaphane reached the highest at 2 minute,the content of sulforaphane was respectively 36.93?g/g and 40.70 ug/g.3.The myrosinase activity in broccoli decreased with cooking time prolonged,but there was no significant difference among the four treatments(p < 0.05);the permeability of cell membrane increased with cooking time prolonged.4.Exogenous addition of myrosinase can increased the conversion rate of glucoraphanin to sulforaphane;the conversion rate was highest under steaming treatment(42.98%).5.In vitro simulated gastrointestinal digestion,the content of glucoraphanin and sulforaphane in broccoli decreased with the prolongation of treatment time,the content of glucoraphanin in broccoli under microwaving treatment for 30 min decreased by 35.8 ug/g.