Evaluation of Alpha-Amylase Inhibitory, Antioxidant, and Antimicrobial Potential and Phytochemical Contents of Polygonum hydropiper L.

Abstract

<jats:p>Polygonum hydropiper L. is a traditionally used medicinal plant. The present study was designed to explore the α-amylase inhibitory, antioxidant, and antimicrobial activities of Polygonum hydropiper L. Polarity-based solvent extracts (n-hexane, acetone, chloroform, methanol, ethanol, and water) of Polygonum hydropiper leaves and stem were used. Antioxidant activity was assessed by free radical scavenging assay (FRAP) and 2,2-diphenylpicrylhydrazyl (DPPH) free radical scavenging activity methods. Quantitative phytochemical analyses suggested that the stem of Polygonum hydropiper L. contains higher levels of bioactive compounds than its leaves (p &lt; 0.05). The results suggested that stem-derived extracts of Polygonum hydropiper L. are more active against bacterial species, including two Gram-positive and three Gram-negative strains. Moreover, our results showed that the bioactive compounds of Polygonum hydropiper L. significantly inhibit α-amylase activity. Finally, we reported the polarity-based solvent extracts of Polygonum hydropiper L. and revealed that the stem, rather than leaves, has a high antioxidant potential as measured by FRAP and DPPH assay with IC50 values of 1.38 and 1.59 mg/mL, respectively. It may also be deducted from the data that the Polygonum hydropiper L. could be a significant candidate, which should be subjected to further isolation and characterization, to be used as an antidiabetic, antimicrobial and antioxidant resource in many industries, like food, pharmaceuticals and cosmetics.</jats:p>

Investigation on the Phytochemical Composition, Antioxidant and Enzyme Inhibition Potential of Polygonum Plebeium R.Br: A Comprehensive Approach to Disclose New Nutraceutical and Functional Food Ingredients

“…[33,34] FRAP and CUPRAC assays were used to determine metal reducing power activity of P. plebeium, where again the PP-E fraction was the most active in both the assays with values of 369.54 � 1.70 and 411.33 � 15.49 mgTE/g extract, respectively, followed by PP-M (Table 3). Our results are supported with similar published activity trends in these assays, [19,[35][36][37][38][39][40] where phenol rich ethyl acetate plant extracts are more active than any other extracts in both CUPRAC and FRAP assays, therefore, our findings (Table 3) are consistent with previous results which supported the hypothesis that phenolic and flavonoid-rich plant extracts afford the strongest radical scavenging and reducing power activity. Therefore, the higher DPPH, ABTS and CUPRAC and FRAP antioxidant activities of the PP-E fraction of P. plebeium can be linked to their higher total bioactive contents as well as the presence of flavonoids and phenolics.…”

The genus Polygonum: An updated comprehensive review of its ethnomedicinal, phytochemical, pharmacological activities, toxicology, and phytopharmaceutical formulation

“…Using the FRAP (ferric reducing antioxidant power) and DPPH methods, Nasir et al [ 137 ] investigated the antioxidant potential of extracts from P. hydropiper leaves and stems using water, ethanol, methanol, chloroform, acetone, and n-hexane. The research results indicated that the stem rather than the leaves had substantial antioxidant potential as determined by the DPPH and FRAP assays, with IC 50 of 1.59 and 1.38 mg/mL, respectively.…”

An Update on Phytochemicals and Pharmacological Activities of the Genus Persicaria and Polygonum

“…Authors correlated these promising activities with the presence of the sesquiterpene polygodial in P. acuminata extracts [ 25 ] and the chalcones cardamonin and pashanone present in P. ferruginea extracts [ 8 ]. Moreover, P. chinensis , P. hydropiper , P. maculosa , P. punctata , P. senegalensis , P. aviculare and P. cognatum resulted in both antifungals and antibacterials, highlighting the MICs values obtained for isolated compounds confertifolin and drimenol from P. hydropiper essential oil and polygodial from its chloroformic extract (MICs between 0.39 and 125 µg/mL comparable with standard drugs) [ 71 , 72 , 73 , 74 , 75 ]. Finally, P. capitata , P. glabra , P. minor , P. tinctoria and P. perfoliatum were reported in the literature only as antibacterials, remarking the high activity against S. aureus, E. coli, K. pneumoniae and N. gonorrhoeae of flavonoid-enriched fractions of aqueous extracts of P. capitata (MICs comparables to ciprofloxacin) [ 48 ].…”

“…), leaves’s extract showed higher effectiveness than standard glibenclamide, diminishing blood glucose levels between 48.8 and 58.2% for the extract and 42.1% for glibenclamide (at dose 10 mg/kg b.w.). Furthermore, the extracts of the leaves and stems (principally n -Hex, Chl and MeOH extracts) displayed α-amylase inhibitory activities, with IC 50 values between 1.03 and 3.517 mg/mL [ 75 ]. This enzyme can increase the blood sugar level, as hydrolyses (1,4)-α- d -glycosidic linkages in polysaccharides contain three or more (1,4)-α-linked D-glucose units.…”