dc.description.abstract | Microgreens are recognized as new crops and potential foods of the future, because
they are a rich source of highly valuable bioactive compounds with health-beneficial effects.
Besides fresh consumption, microgreens can be successfully used for the production of some
novel food products. Most often cultivated and analysed microgreens species are from Amaranthaceae
families, primarily beet, chard and amaranth. Previous characterization of amaranth
microgreens has showed a high content of different biocompounds such as vitamins, phenolic
compounds and betalains. However, functional products from amaranth microgreens have only
become attractive in recent years and have not been widely investigated until now. So, the aim
of this study was production of cold pressed juice of amaranth microgreens and determination
of its total phenolic (TPC) and flavonoid (TFC) content, as well as evaluation of antioxidant
activity. Amaranth (Amaranthus tricolor L.) microgreens juice was obtained by pressing in a
super slow cold juicer and further analyzed by well-known spectrophotometric methods such as
Folin-Ciocalteu’s assay for TPC and colorimetric assay with aluminum chloride for TFC. Antioxidant
activity was evaluated using the following assays: ABTS + radical scavenging activity
(ABTS +), DPPH radical scavenging activity (DPPH ) and Ferric reducing antioxidant power
assay (FRAP), which are based on different mechanisms of activity. Results were expressed in
mg equivalents (gallic acid, quercetin and trolox) per 100mL of the juice. Determined TPC and
TFC were 50.86 ± 0.26 mg GAE/100 mL and 45.94 ± 0.63 mg QE/100 mL, respectively. Results
for the antioxidant activity were 101.61 ± 2.55 mg TE/100 mL for ABTS +, 14.98 ± 0.06 mg
TE/100 mL for DPPH and 99.93 ± 1.32 mg TE/100 mL for FRAP. As can be seen, the antioxidant
activity of the amaranth juice high depends on the nature of amaranth biocompounds
and their affinity according to ABTS + and DPPH radicals, i.e., the tendency to reduce the
[Fe3+-(TPTZ)2]3+ complex. Finally, the cold pressed amaranth microgreens juice showed the
high content of phenolic compounds and good antioxidant activity using some in vitro screening
assays, so it can be potentially defined as a novel functional product, however further research
is necessary. | sr |