Anethum graveolens L. in vitro cultures : a potential source of bioactive metabolites, phenolic acids and furanocoumarins

Abstract In vitro cultures of Anethum graveolens (dill) were maintained on the Linsmaier and Skoog (LS) medium – three variants, and the Murashige and Skoog (MS) medium – seven variants, which contained different amounts of plant growth regulators, cytokinin (BAP) and auxin (NAA) (from 0.1 mg l−1 to 3.0 mg l−1). Methanolic extracts from in vitro grown biomass were analyzed by HPLC for free phenolic acids and furanocoumarins. The total amounts of free phenolic acids on the LS medium variants were similar (35.23–38.65 mg 100 g−1 DW), but higher on the MS variants, ranging from about 66 mg 100 g−1 DW to 100 mg 100 g−1 DW. The main metabolites were: p-hydroxybenzoic acid (max. 24.41 mg 100 g−1 DW) on the LS−based media, and salicylic acid (max. 57.88 mg 100 g−1 DW) and p-hydroxybenzoic acid (max. 36.27 mg 100 g−1 DW) on the MS−based media. The total amounts of furanocoumarins were lower, as they did not exceed 8.5 mg 100 g−1 DW on the LS media and 25 mg 100 g−1 DW on the MS media. The main compounds in this group were bergapten (max. 15.01 mg 100 g−1 DW) and marmesin (max. 8.12 mg 100 g−1 DW). The MS variant containing 0.5 mg l−1 BAP and 2.0 mg l−1 NAA was proposed as the best production medium for both groups of metabolites. The maximum total amounts of free phenolic acids obtained in the in vitro grown biomass were slightly higher than their amounts in the fruits of the mother plant analyzed for comparison (99.66 mg 100 g−1 DW and 93.34 mg 100 g−1 DW, respectively); the maximum total amounts of furanocoumarins were approximately 1.8 times higher than in the fruits (24.26 mg 100 g−1 DW and 13.67 mg 100 g−1 DW, respectively).</jats:p

Biotransformation of hydroquinone and 4-hydroxybenzoic acid in Schisandra chinensis (Chinese magnolia vine) in vitro cultures

Optimization of the process of biotransformation of hydroquinone into its β-D-glucoside – arbutin, was performed in agitated shoot cultures of Schisandra chinensis. The optimisation involved testing various concentrations of the precursor and different ways of administering it. Arbutin was accumulated mainly in the in vitro cultured biomass (85.2–98.6%). By optimizing the process, a 2.26-fold increase in the overall product content was obtained. The highest amount (17.8 mg·g–1 DW) was found after administering 384 mg·l–1 hydroquinone in a dose divided into two portions. An experiment with the biotransformation of 4-hydro- xybenzoic acid did not produce arbutin but a mixture of two products of glucosylation of the precursor – hydroxybenzoic acid 4-O-β-glucopyranoside and 4-hydroxybenzoic acid β-glucopyranosyl ester. The identity of all biotransformation products was confirmed by 1H-NMR analysis. The results for the production of arbutin by the biotransformation of hydroquinone are of potential practical importance. On the other hand, the fact of confirming the presence of two glucosylation products has a great cognitive value

Sex-related differences in the dioecious species Rumex thyrsiflorus Fingerh : analysis of the content of phenolic constituents in leaf extracts

Rumex thyrsiflorus Fingerh. is mentioned as a European folk medicinal plant. This species has also been traditionally used as an edible plant in Eastern Europe because of its nutritional value. During the study, qualitative and quantitative sex-related differences of phenolic constituents in methanolic leaf extracts of R. thyrsiflorus were evaluated. The presence of the same substances (nine phenolic acids before, and six phenolic acids after acid hydrolysis, nine flavonoids, and a catechin) was estimated in both female and male specimens, using the HPLC-DAD method. A statistically significant higher content of eleven constituents in female plant extracts (acids: chlorogenic, p-coumaric, cryptochlorogenic, gallic, protocatechuic, neochlorogenic, vanillic; flavonoids: quercitrin, rhamnetin, rutoside; and a catechin) was shown. This is the first report concerning the relation between the sex and the content of biologically active phenolic secondary metabolites in leaf extracts of R. thyrsiflorus. Female plants of R. thyrsiflorus could be useful for pharmaceutical purposes as a preferential source of bioactive phenolic acids, flavonoids and especially catechin