Evaluation of Antioxidant Systems and Ascorbate-Glutathione Cycle in Feijoa Edible Flowers at Different Flowering Stages

Abstract

Background: Feijoa (Acca sellowiana (O. Berg)) was initially introduced as an ornamental plant, but nowadays, it is widely cultivated for the numerous beneficial properties of its edible fruits. Feijoa flowers have been included in the list of edible flowers, but despite this, they are still considered niche products due to consumer skepticism and lack of publicity. Methods: This study evaluated the physicochemical traits, antioxidant system, and ascorbate-glutathione cycle in feijoa flowers at five flowering stages based on the Biologische Bundesanstalt, Bundessortenamt und CHemische Industrie (BBCH) scale. Results: The results showed that the optimal stage to harvest feijoa flower is the F2 stage characterized by high bioactive compounds content. Furthermore, the enzymes involved in oxidative stress and the ascorbate-glutathione cycle showed different trends during the flowering stages. Conclusions: This study provides new evidence to understand the possible role of bioactive compounds and ascorbate-glutathione cycle in the regulation of flower development, defining the optimal stage to harvest flowers.

Influence of Cold Storage on Pear Physico-Chemical Traits and Antioxidant Systems in Relation to Superficial Scald Development

“…Catalase (EC 1.11.1.6) activity was assayed according to the method described by Magri et al [34] with slight modifications. The mixture for reaction containing potassium phosphate buffer (100 mM; pH 7), H 2 O 2 (20 mM) and crude enzyme extract.…”

“…H 2 O 2 is further converted to harmless water by APX and CAT, which belong to two different classes of H 2 O 2 -scavenging enzymes with different affinities to the substrate [48]. APX reduces H 2 O 2 to H 2 O by utilizing ascorbate as an electron donor, and ascorbate is then regenerated by the ascorbate-glutathione cycle [34]. CAT activity showed the highest values at harvest and decreased in the peel and flesh of different pear cultivars/selections during storage, with higher values in flesh compared to that in peel.…”

Melatonin treatment reduces qualitative decay and improves antioxidant system in highbush blueberry fruit during cold storage

“…The total polyphenol content (POL) was determined by the Folin–Ciocalteu method and expressed as g of gallic acid equivalents kg −1 , whereas the total flavonoid content (FLA) was determined using the aluminum chloride colorimetric method and expressed as g of catechin equivalents kg −1 , as reported by Petriccione et al 36 . The total monomeric anthocyanins were detected spectrophotometrically as described by Magri et al 37 . and expressed as g of cyanidin‐3‐glucoside equivalents kg −1 .…”

“…Lipoxygenase activity (EC 1.13.11) (LOX) was evaluated as described by Adiletta et al ., 37 with slight modification. Frozen powder (1:4 w/v) was homogenised in extraction buffer and LOX activity was evaluated using a reaction mix with sodium phosphate buffer (100 mmol L −1 , pH 6), linoleic acid sodium salt (5 mmol L −1 ) and crude enzyme extract (10 μL) and its activity was expressed as mmol kg −1 .…”

Influence of some environmental factors on the feijoa (Acca sellowiana [Berg] Burret): A review

“…For humans, the flower petals are edible and contain, according to the variety, high concentrations of anthocyanins, flavonoids, total phenols, increased antioxidant activity and high soluble solids content (Amarante et al, 2019). Magri et al (2020) found that the petals attain the highest peak of polyphenols, anthocyanins and ascorbic acid in the F2 state, when the petals continue to open and the anthers and filaments have a dark red color, according to the BBCH scale (Ramírez & Kallarackal, 2018b).…”