Cultures of Medicinal Plants In Vitro as a Potential Rich Source of Antioxidants

Abstract

AbstractThe search for a new natural source of antioxidants has been, for more than a decade, one of the most dynamically developing directions of scientific research conducted by various research centers around the world.Numerous species of medicinal plants that are a rich source of natural antioxidants have not been fully explored yet. Cultures of such plant species in vitro can also be a potential rich source of antioxidants.The largest group of plant-based antioxidants is compounds with the structure of polyphenols. They are metabolites frequently found in numerous medicinal plants.The aim of this chapter is to present the most interesting results of our biotechnological research that have proven the very high biosynthetic potential of cells of medicinal plants grown in vitro, obtained in the production of selected subgroups of polyphenols – phenolic acids, flavonoids specific to the genus Scutellaria, phenylpropanoid glycosides, catechins, and the dibenzocyclooctadiene lignans (Schisandra-type lignans).As part of the presented research, the conditions for cultivating cultures in vitro were optimized (testing of basal media, quality and quantity of PGRs, feeding with biosynthetic precursors, elicitation, light conditions, and different types of in vitro cultures). The optimization was conducted for in vitro cultures of Aronia spp., Cistus × incanus, Hypericum perforatum (cvs. Elixir, Helos, and Topas), Scutellaria spp., Verbena officinalis, and Schisandra spp. The results of this optimization work are of an application value. Selected types of in vitro cultures of the plant species tested by us are a very rich source of various subgroups of polyphenols, including depsides, selected Scutellaria specific flavonoids (incl. baicalin and wogonoside), selected phenylpropanoid glycosides (incl. verbascoside and isoverbascoside), selected catechins (incl. catechin and epicatechin gallate), and selected Schisandra-type lignans (incl. gomisin A and schisantherin B). The obtained amounts of these compounds are very often, from a few to a several times, higher than in the extracts of plant material from plants growing in vivo (in open air) analyzed for comparison. Extracts from the biomass grown in vitro of some plant species analyzed for antioxidant potential have high antioxidant activity as determined by various methods (DPPH, FRAP, CUPRAC, QUENCHER-CUPRAC, Fe2+ chelating activity, and reducing power assay).KeywordsIn vitro culturesPlant-derived antioxidantsPhenolic acids Scutellaria flavonoidsPhenylpropanoid glycosidesCatechinsDibenzocyclooctadiene lignans Schisandra-type lignans Aronia species Cistus × incanus Hypericum perforatum cultivars Scutellaria species Schisandra species Verbena officinalis