Abstract:
Poruthumaan is an underutilized medicinal creeper widely grown in the Northern
Province of Sri Lanka and traditionally consumed for relieving menstrual discomfort, enhancing
bone strength, and managing arthritis. Despite its long-standing use in local diets, its nutritional
and functional values have not been scientifically reported. This study aimed to analyze the
nutritional composition, mineral profile, anti-nutritional factors and anti-diabetic potential of
Poruthumaan leaf powder. Poruthumaan leaf powder was prepared by grinding cabinet-dried
(40°C for 12 hours) mature leaves into fine powder. The sample was analyzed for nutritional
composition, mineral profile, anti-nutritional factors and anti-diabetic potential (using α-amylase
inhibition assay). The results revealed that dried Poruthumaan leaf powder is highly rich in fiber
(24.12 ± 1.39%). The crude protein, crude fat, and ash contents of the dried leaf powder were
8.94 ± 0.08%, 1.07 ± 0.02%, and 8.37±0.09%, respectively. Mineral analysis reported a notably
high calcium content (1835±10.2 mg/100g). Further, the results demonstrated that Prothumaan
leaf powder is a good source of other minerals such as Mn, Zn, Fe and Mg. Anti-nutritional
factors such as tannins (hydrolysable tannin (92.9 ± 067 mg/100g) and condensed tannin (1.08 ±
0.12 mg/100g) and oxalates (352.24 ± 3.18 mg/100g) were detected at concentrations similar to
those of commonly consumed medicinal leaves. The α-amylase inhibition assay showed strong
enzyme inhibitory activity (IC50=28.05 μg/mL) comparable to the standard (Quercetin)
(IC50=35.69 μg/mL). This study revealed that the first scientific evidence validating the
nutritional richness and bioactive potential of Poruthumaan leaf. Future studies should focus on
bioactive compounds profiling and underlying mechanisms responsible for the anti-diabetic
effects, assessing mineral bioavailability and safety, and validate the functional potential through
in-vivo experiments.
