Abstract:
Background: Exploring natural antioxidants derived from underutilized sources holds substantial
potential for improving human health and nutrition by mitigating oxidative stress and associated
diseases.
Objective: To evaluate the antioxidant capacity of extracts derived from underutilized fruits and
leaves, specifically Lovi (Flacourtia inermis), Veralu (Elaeocarpus serratus), Polos (Artocarpus
heterophyllus), Bilin (Averrhoa bilimbi), Siyambala (Tamarindus indica), and Ambarella
(Spondias dulcis) sourced from Sri Lanka
Methods: The fruits and leaves underwent extraction processes using water and methanol. For the
hot water extraction, 10 grams of dried and powdered sample were used. For the maceration
process, 5 grams of dried and powdered samples were soaked in a mixture of water and methanol.
This involved preparing a hot water extract, a room temperature macerated water extract, and a
methanol extract. Subsequently, these extracts were assessed for their antioxidant activity using
in-vitro bioassays, namely the DPPH assay (2,2-diphenyl-1-picrylhydrazyl) and the ABTS assay
(2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid).
Results: Among fruit extracts, Veralu and Lovi hot water extracts showed the highest scavenging
activity as 90.46% and 90.53% respectively at 1 mg/mL. Among the leaf extracts, Veralu leaf hot
water extract and macerated water extract displayed the highest scavenging activity with values
90.74% and 90.53%, respectively at 1 mg/mL, suggesting their potential as valuable sources of
antioxidants by the ABTS assay. All three fruit and leaf extracts of Veralu depicted high
scavenging activity values by the DPPH assay. Among fruit extracts, Veralu hot water extract
displayed scavenging activity as 86.3% and for the macerated water extract as 80.55% at 1
mg/mL. Among the leaf extracts, Veralu leaf hot water extract and macerated methanol extract
displayed scavenging activity as 86.30% and 77.90%, respectively at 1 mg/mL. Ascorbic acid was
used as the positive control where 88.42% was found for ABTS and 61.10% was found for DPPH
as radical scavenging values.
Conclusion: Among the six fruits studied, Veralu fruit and leaf extracts exhibited high antioxidant
activity in both the DPPH and ABTS assays, indicating their potential as rich sources of
antioxidants.
