Phytochemical Analysis, Biological Activities, and Docking of Phenolics from Shoot Cultures of Hypericum perforatum L. Transformed by Agrobacterium rhizogenes.

Hypericum perforatum transformed shoot lines (TSL) regenerated from corresponding hairy roots and non-transformed shoots (NTS) were comparatively evaluated for their phenolic compound contents and in vitro inhibitory capacity against target enzymes (monoamine oxidase-A, cholinesterases, tyrosinase, α-amylase, α-glucosidase, lipase, and cholesterol esterase). Molecular docking was conducted to assess the contribution of dominant phenolic compounds to the enzyme-inhibitory properties of TSL samples. The TSL extracts represent a rich source of chlorogenic acid, epicatechin and procyanidins, quercetin aglycone and glycosides, anthocyanins, naphthodianthrones, acyl-phloroglucinols, and xanthones. Concerning in vitro bioactivity assays, TSL displayed significantly higher acetylcholinesterase, tyrosinase, α-amylase, pancreatic lipase, and cholesterol esterase inhibitory properties compared to NTS, implying their neuroprotective, antidiabetic, and antiobesity potential. The docking data revealed that pseudohypericin, hyperforin, cadensin G, epicatechin, and chlorogenic acid are superior inhibitors of selected enzymes, exhibiting the lowest binding energy of ligand-receptor complexes. Present data indicate that H. perforatum transformed shoots might be recognized as an excellent biotechnological system for producing phenolic compounds with multiple health benefits.

Effects of polysaccharide elicitors on secondary metabolite production and antioxidant response in Hypericum perforatum L. shoot cultures.

The effects of polysaccharide elicitors such as chitin, pectin, and dextran on the production of phenylpropanoids (phenolics and flavonoids) and naphtodianthrones (hypericin and pseudohypericin) in Hypericum perforatum shoot cultures were studied. Nonenzymatic antioxidant properties (NEAOP) and peroxidase (POD) activity were also observed in shoot extracts. The activities of phenylalanine ammonia lyase (PAL) and chalcone-flavanone isomerase (CHFI) were monitored to estimate channeling in phenylpropanoid/flavonoid pathways of elicited shoot cultures. A significant suppression of the production of total phenolics and flavonoids was observed in elicited shoots from day 14 to day 21 of postelicitation. This inhibition of phenylpropanoid production was probably due to the decrease in CHFI activity in elicited shoots. Pectin and dextran promoted accumulation of naphtodianthrones, particularly pseudohypericin, within 21 days of postelicitation. The enhanced accumulation of naphtodianthrones was positively correlated with an increase of PAL activity in elicited shoots. All tested elicitors induced NEAOP at day 7, while chitin and pectin showed increase in POD activity within the entire period of postelicitation. The POD activity was in significantly positive correlation with flavonoid and hypericin contents, suggesting a strong perturbation of the cell redox system and activation of defense responses in polysaccharide-elicited H. perforatum shoot cultures.

Generation of flavor compounds by biotransformation of genetically modified hairy roots of Hypericum perforatum (L.) with basidiomycetes.

Altogether, 14 basidiomycetes (12BAD, 95PCH, 9WCOC, 5PSA, 96BCI, 331SHIBD, 4MSC, 74HFA, 220MPS, 115PFLA, 111 ICO C, 16LED, 6TSU, and 61LYP) were grown on solid and in liquid media using hairy roots of genetically modified Hypericum perforatum (L.) as the only source of carbon and nitrogen. After the first screening by GC-MS/MS-O, two fungi (115PFLA and 61LYP) which resulted in the most pleasant complex natural flavor by biotransformation were selected for further analysis. Twenty-four new volatile compounds were produced, from which 21 were identified (ethyl hexanoate, ethyl octanoate, benzaldehyde, 2-undecanone, (E,E)-2,4-decadienal, 1-octen-3-one, (E)-2-nonenal, ethyl nonanoate, 2-heptenal, 1-methoxy-4-methylbenzene, 3-octanone, 1-decen-3-one, (E)-2-octenal, 1-octen-3-ol, ß-linalool, ±trans-nerolidol, anisole, methyl benzoate, 2-pentylfuran, 1,3-dichloro-2-methoxybenzene, and 1-dodecanol). Thereof, 15 compounds were perceived at the ODP, from which 13 were identified. Compound identification was performed by comparison of Kovats indices (KI) and mass spectra to those of authentic reference compounds on a polar VF-WAXms column using headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS).