Abstract:
Noni (Morinda citrifolia L.) fruit, locally known as ‘Ahu’, is a traditional medicinal
plant in Sri Lanka, but not commonly consumed or processed. However, noni juice has
gained global popularity as a wellness drink. In this study, we evaluated the bioactive
components and antioxidant, anti-diabetic, and anti-inflammatory activities of pasteurized
noni juice, expressed per 1 g (FW) of the fruit pulp. The results showed that the
total phenolic content was (165.85 ± 0.84) μmol gallic acid equivalent, total flavonoids
were (6.36 ± 0.22) μmol rutin equivalent, ascorbic acid content was (24.68 ± 0.89)
μg, monomeric anthocyanin content was (8.91 ± 0.96) μg, β-carotene content was
(0.15 ± 0.02) μg, and lycopene content was (0.14 ± 0.01) μg. The juice exhibited
antioxidant activities as observed with phosphomolybdenum reduction (14.04 ± 0.05)
mg ascorbic acid equivalent), ABTS radicals scavenging (723.98 ± 2.67) mg Trolox
equivalent, DPPH radicals scavenging (645.98 ± 2.45), lipid peroxidation inhibition
(589.98 ± 2.56) mg ascorbic acid equivalent), nitric oxide inhibition (157.08 ± 1.45)
mg ascorbic acid equivalent, and singlet O2 inhibition (87.02 ± 2.78) mg gallic acid
equivalent. The juice also exhibited anti-diabetic activities with (11.10 ± 0.07) % and
(16.10 ± 0.03) % of α-amylase and α-glucosidase inhibitory activities, respectively,
at 2 μg/mL. Additionally, the juice showed anti-inflammatory activities such as heatinduced
hemolysis inhibition (30.43 ± 0.39) %, protein denaturation inhibition (33.33
± 0.34) %, and proteinase inhibition (2.25 ± 0.54) %, respectively, at 2 μg/mL. These
findings suggest that pasteurized noni juice from Sri Lanka contains significant amounts
of bioactive compounds and exhibits antioxidant, anti-diabetic, and anti-inflammatory
activities, which could potentially contribute to its health benefits.
