Study On The Chemical Constituents Of Jindenglong And Their Biological Activity

Jindenglong is the dried persistent calyx or persistent calyx with fruit of Physalis alkekengi L.var.franchetii（Mast.）Makino.In China,this medicine is widely distributed and can be harvested during autumn when it is fully matured,and the persistent calyx turns red or orange-red.It is known for its many functions such as clearing away heat and toxins,resolving phlegm,relieving pharynx,as well as promoting diuresis.Jindenglong is a known source of various chemical components,some of which have been linked to anti-inflammatory,antioxidant,antitumor,hypoglycemic,and other biological activities.Recent studies have demonstrated that physalins and flavonoids,in particular,possess significant anti-inflammatory effects.However,the underlying chemical basis of Jindenglong’s antioxidant and hypoglycemic activities remains poorly understood.To address this knowledge gap,this paper presents a comprehensive study of the chemical constituents of Jindenglong,as well as an evaluation of its antioxidant and hypoglycemic activities.In this study,28 compounds were isolated from the 70%ethanol extract of Jindenglong by silica gel column chromatography,Sephadex LH-20 column chromatography,reverse phase ODS column chromatography,semi-preparative HPLC and other separation methods.The structures of these compounds were identified asα-tocopherolquinone（1）,（-）-3-O-palmitoylloliolide（2）,columbianetin acetate（3）,osthole（4）,columbianadin（5）,ursolic acid（6）,xanthotoxin（7）,p-hydroxyphenethyl anisate（8）,rhamnazin（9）,1-linoleoylglycerol（10）,isophysalin B（11）,physalin B（12）,loliolid（13）,angelol M（14）,p-hydroxyphenylferulate（15）,physalin A（16）,physalin W（17）,14-deoxy-11,12-dide-hydroandrographolide（18）,4,7-didehydroneophysalin B（19）,daucosterol（20）,physalin O（21）,physalin L（22）,syringaresinol（23）,physalin D（24）,3α-methoxy-2,3-dihydro-4,7-didehydrophysalin B（25）,luteolin-7-O-glucoside（26）,apigetrin（27）,thermopsoside（28）.Compounds 1-5,7-8,14-15and 18 were isolated from this plant for the first time.The antioxidant activity and hypoglycemic activity of some compounds isolated from Jindenglong were preliminarily screened and evaluated by the DPPH radical scavenging method andα-glucosidase inhibition activity assay.The results of DPPH radical scavenging experiments showed that compound 9 had a stronger scavenging effect on DPPH radical with an EC₅₀ value of 0.12 mg/m L,which was close to that of the positive control vitamin C(EC₅₀ value of 0.13 mg/m L);compounds 15and 26 had a slightly weaker scavenging effect on DPPH radical than the positive control with EC₅₀ values of 0.22 and 0.23 mg/m L,respectively.Theα-glucosidase inhibition activity assay revealed that,among the compounds involved in the activity screening,compounds 1,6,8,10,20 and 28 inhibitedα-glucosidase by more than 50%.The IC₅₀ values of these compounds againstα-glucosidase were determined,and the results showed that compounds 6 and 20 showed stronger inhibitory activity againstα-glucosidase with IC₅₀ values of 8.06 and 34.95μg/m L,respectively.Compounds 1,8,10 and 28 showed weak inhibitory activity againstα-glucosidase with IC₅₀values of 1.17,0.20,0.26 and 0.26 mg/m L,respectively.The selected positive control was acarbose,and its IC₅₀ value forα-glucosidase was 0.17μg/m L.