This study presents the proximate and mineral composition of Peperomia pellucida L., an underexploited weed plant in Malaysia. Proximate analysis was performed using standard AOAC methods and mineral contents were determined using atomic absorption spectrometry. The results indicated Peperomia pellucida to be rich in crude protein, carbohydrate and total ash contents. The high amount of total ash (31.22%)suggests a high-value mineral composition comprising potassium, calcium and iron as the main elements. The present study inferred that Peperomia pellucida would serve as a good source of protein and energy as well as micronutrients in the form of a leafy vegetable for human consumption.
This study aimed to compare the effect of fermentation and drying on the organoleptic characteristic, total phenolic content, antioxidant and anti-inflammatory activities of Peperomia pellucida (L.) Kunth tea with commercial Camellia sinensis tea. The phenolic content, antioxidant and anti-inflammatory activities in P. pellucida were significantly (p
Bioassay-guided isolation protocol was performed on petroleum ether extract of Peperomia blanda (Jacq.) Kunth using column chromatographic techniques. Five compounds were isolated and their structures were elucidated via one-dimensional (1D) and two-dimensional (2D) NMR, gas chromatography mass sectroscopy (GCMS), liquid chromatography mass spectroscopy (LCMS), and ultraviolet (UV) and infrared (IR) analyses. Dindygulerione E (a new compound), and two compounds isolated from P. blanda for the first time-namely, dindygulerione A and flavokawain A-are reported herein. Antimicrobial activity was screened against selected pathogenic microbes, and minimum inhibitory concentrations (MIC) were recorded within the range of 62-250 μg/mL. Assessment of the pharmacotherapeutic potential has also been done for the isolated compounds, using the Prediction of Activity spectra for Substances (PASS) software, and different activities of compounds were predicted. Molecular docking, molecular dynamics simulation and molecular mechanics/Poisson-Boltzmann Surface Area (MM-PBSA) calculations have proposed the binding affinity of these compounds toward methylthioadenosine phosphorylase enzyme, which may explain their inhibitory actions.
This study aims to elucidate the anti-inflammatory mechanism of Peperomia pellucida (L.) Kunth in human retinal pigment epithelial cell line (ARPE-19) as stimulated by high glucose (34 mM and 68 mM), and advanced glycation end product (AGE) under different glucose (17 mM, 34 mM and 68 mM) environments via the nuclear factor kappa B (NF-κB) and peroxisome proliferator activated receptor gamma (PPAR-γ) signalling pathways. The cytotoxicity of P. pellucida in ARPE-19 cells was evaluated with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. The genes and proteins expression of nine pro-inflammatory, angiogenic and antioxidant markers, including glutathione peroxidase (GPx), interleukin 8, matrix metalloproteinase 2, monocyte chemoattractant protein 1, NF-κB, PPAR-γ, receptor for AGE (RAGE), soluble RAGE (sRAGE), and vascular endothelial growth factor in P. pellucida-treated ARPE-19 cells were compared to non-treated control via real-time polymerase chain reaction and western blot. Both P. pellucida methanolic extract (1.5 mg/mL and 3 mg/mL) and ethyl acetate fraction (4 mg/mL) were non-toxic to ARPE-19 cells and demonstrated cytoprotective effect against the high glucose (34 mM) and AGE (17 mM glucose)-induced cellular stress. High glucose and AGE activated the pro-inflammatory signalling in ARPE-19 cells, as evidenced by the increased NF-κB p65 phosphorylation, up-regulation of pro-inflammatory and angiogenic mediators (p<0.05) but reduced GPx, PPAR-γ and sRAGE protein expression. Both P. pellucida methanolic extract (3 mg/mL) and ethyl acetate fraction (4 mg/mL) suppressed (p<0.05) the pro-inflammatory and angiogenic markers expression under high glucose and AGE environment. The main phytochemicals identified in P. pellucida were dillapiole, 2,4,5-trimethoxystyrene, 9-octadecenoic acid, and pheophorbide A-methyl ester which displayed relatively strong binding affinity towards NF-κB p65 and PPAR-γ proteins in molecular docking analysis. This study has demonstrated that P. pellucida is a potential alternative anti-inflammatory source for managing diabetic retinopathy via NF-κB and PPAR-γ signalling.