Callus cultures of Hypericum perforatum L. a novel and efficient source for xanthone production

Hypericum perforatum callus cultures exhibited qualitatively and quantitatively different phenolic profile compared to wild-growing plants (WGP). This study revealed the presence of phenolic acids, flavonoid glycosides and aglycones, flavan-3-ols and naphtodianthrones in callus and WGP extracts. Phloroglucinols were detected only in WGP, while xanthones were exclusively found in callus cultures. Among the caffeoyl-, coumaroyl- and feruloyl-quinic acid derivatives identified in both extracts, 3-feruloylquinic acid was identified only in callus cultures. Flavonoid glycosides were represented with quercetin and kaempferol derivatives in both extracts, whereas calli produced a new flavone of luteolin type. Callus cultures showed superior potential for the production of quercetin 6-C-glucoside, hyperoside and kaempferol 3-O-glucoside compared to WGP. Flavonoid aglycones, quercetin and kaempferol were found in both extracts, while I3,II8-biapigenin was accumulated only in WGP. Catechin and procyanidin dimers were abundant in WGP, while epicatechin was dominant flavan-3-ol in callus cultures. With respect to naphtodianthrones, undifferentiated calli were able to produce only pseudohypericin, but in minor amounts compared to WGP. Among the eighteen detected xanthones, mangiferin, mangiferin C-prenyl hexoside and 1,3,6,7-tetrahydroxyxanthone were found as the major compounds in callus cultures. Four xanthones identified as roeperanone, 1,3,7-trihydroxy-2-(2-hydroxy-3-methyl-3-butenyl)-xanthone, trihydroxy-1-methoxy C-prenyl xanthone and 1,5-dihydroxy-2-methoxyxanthone were shown for the first time in H. perforatum callus extracts. Altogether, these results indicated that H. perforatum callus cultures represent a promising experimental system for the production of novel xanthone derivatives and other bioactive metabolites of commercial importance.