Phytoconstituents, GC-MS Characterization of Omega Fatty Acids, and Antioxidant Potential of Less-Known Plant Rivina humilis L.

Rivina humilis L. (Petiveriaceae), commonly known
as the pigeon berry, accumulates betalains in berries. The present
study was focused on identifying the phytoconstituents, mineral
content, fatty acid composition, phenolics, flavonoids, antinutritional
factors, and antioxidant activities of different plant parts
(leaf, stem, root, and seeds), which are otherwise not well explored.
Phytoconstituent analysis revealed seeds as a potential source of
carbohydrates (50.15 g/100 g), proteins (10.96 g/100 g), and fats
(11.25 g/100 g). Roots showed the highest fat (17.66 g/100 g) and
dietary fiber (81.49 g/100 g). Leaves and roots contain more iron
(29.59 and 29.39 mg/100 g), whereas seed has high zinc content
(12.09 mg/100 g). Leaf oil showed 47.83 g/100 g of omega-3-fatty
acid, confirmed by GC-MS analysis. Seed oil showed 22.23 g/100,
44.48 g/100, and 24.04 g/100 g of palmitic, oleic, and linoleic acids, respectively. The leaf extract has the highest TPC (597.55 mg/
100 g), followed by the seed (421.68 mg/100 g). The leaf’s 80% ethanolic extract had high TFC (2442.19 mg/100 g), followed by
70% methanolic extract (1566.25 mg/100 g). The antinutritional profile indicated significant phytic acid and oxalates in the leaf (9.3
g/100 and 2.07 g/100 g) and stem (6.9 and 1.58 g/100 g) and low tannin content (<0.5 g/100 g). The leaf’s 80% ethanolic extract
exhibited double the TAA than 70% methanolic extract (1.52 g/100 g). The leaf with an 80% ethanolic extract had the lowest DPPH
and ABTS radical scavenging EC50 (2.22 and 0.37 mg/mL). The leaf with an 80% ethanolic extract (479.73 mg/100 g) and seed
(391.14 mg/100 g) had the highest FRAP activity. Our study proves that different parts of R. humilis had a good content of
phytoconstituents, bioactives, and antioxidant activities. Hence, R. humilis leaves and seeds are a novel source of omega fatty acids
and minerals reported for the first time and have potential applications in the food and pharmaceutical industries.