Stimulation of plant secondary metabolites synthesis in soilless cultivated strawberries (Fragaria × ananassa Duchesne) using zinc-alginate microparticles

An innovative approach to stimulate the production of plant secondary metabolites (PSM) is use encapsulated bioactive agents. Zinc-alginate microparticles [microspheres (ALG/Zn) and microcapsules (CS/ALG/Zn)] were applied near root zone soilless cultivated strawberries (Fragaria × ananassa Duchesne) ensure a constant supply an essential micronutrient zinc ions throughout whole period maturation. Both, ALG/Zn CS/ALG/Zn had positive effect on PSM (total polyphenols, total flavonoids, anthocyanins, flavan-3-ols) synthesis increased antioxidant activity in two strawberry varieties (Albion San Andreas). Treatments with Zn-alginate resulted no visible damages fruits. A two-year study revealed increase ~34% polyphenolic compounds ~23% flavonoids Andreas variety. The highest [ABTS (~37%) DPPH (~38%)] was observed variety treated CS/ALG/Zn. Respectively high anthocyanins both (~54% ~61%, respectively) zinc-alginate successful stimulation strawberries' nutritive value. Encapsulation proved be simple, sustainable, environmentally favorable produce fortified important compounds.