Punicalagin und Punicalin, zwei Gerbstoffe aus den Schalen der Granatäpfel

Abstract

Durch Chromatographie an Cellulose und Sephadex gelang es, aus dem Gesamtgerbstoff der Schalen von Granatapfeln (Punica gramrum L.) zwei Hauptkomponenten als Chemisch einheitliche, kristalline Gerbstoffe zu isolieren, die wir als Punicalagin (5) und Punicalin (6) bezeichnen. 5 ergibt durch partielle Hydrolyse Ellagsaure und 6. Die weitere Hydrolyse und die von 6 liefern Glucose und das Tetralacton 1 oder 2 der Dodecahydroxyquaterphenyltetracarbonslure 3. Letzteres ergibt mit Diazomethan das kristalline Octamethyldedvat l a oder Za, das durch Methylierung mit Dimethylsulfat sowie Diazomethan in den Dodecamethoxyquaterphenyltetracarbonsaure-tetramethylester 3a ubergefiihrt wird. Alkalische Punicalagin and Puaicalin, Two Tannins from Pomegranate PeelTwo crystalline tannins, named punicalagin (5) and punicalin (6), were isolated from a mixture of tannins. obtained from the peels of pomegranates (Punica gramtum), by an extended series of chromatographic separations. Partial acid hydrolysis of 5 yielded ellagic acid and 6. Further hydrolysis and direct hydrolysis of 6 yielded glucose and a tetralactone 1 or 2. On methylation with diazomethane the latter produced a crystalline octamethyl derivative l a or 2a. which on reaction with dimethyl sulfate and an excess of aqueous alkali, followed by methylation with diazomethane, was converted into a dodecamethoxyquaterphenyltetracarboxylic tetramethyl ester 3a. Alkaline hydrolysis of 3a yielded the dibasic acid 3b. The compounds 38 and 3b were identified and characterized by analysis, 'H-NMR-and mass spectroscopic investigations, as well as by synthesis. With diazomethane punicalagin (5) produced a crystalline heptadecamethyl derivative 5a which is cleaved by *) Korrespondenz bitte an diesen Autor richten.

Investigations on antimycobacterial activity of some Ethiopian medicinal plants

“…It was originally isolated from the fruit peel of Punica granatum (Mayer et al, 1977) and is reported to have antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans (Burapadaja and Bunchoo, 1995).…”

An Extract of Pomegranate Fruit and Galangal Rhizome Increases the Numbers of Motile Sperm: A Prospective, Randomised, Controlled, Double-Blinded Trial

“…Both pericarp and aril juice contains hydrolysable tannins, with the pericarp being the far most concentrated source [8] . In the pericarp, the ellagitannins punicalagin A and B predominates, while punicalins, which are partial hydrolysis products of punicalagins [9] , constitute a minor fraction. The ellagitannins are only found in trace amounts in the aril juice [8] .…”

Fatty acid composition and antioxidant capacity of pomegranate seed oil

“…There are flavonols in rind [29,30], fruit [31,32], bark and leaves [31,33]. In addition, pomegranate peel, leaf, and fruit peel are rich in ellagitannins and gallotannins [34,35,36]. The presence of anthocyanidins and anthocyanins, catechins and procyanidins in peel and juice has been reported [33,37,38].…”