Hydrogel Containing Borassus flabellifer L. Male Flower Extract for Antioxidant, Antimicrobial, and Anti-Inflammatory Activity

Abstract

Borassus flabellifer L. is a plant in Arecaceae family, widely distributed and cultivated in tropical Asian countries. The purpose of this study was to identify the bioactive compounds of B.flabellifer L. male flower ethanolic extract and investigate the antioxidant, anti-inflammatory, and antibacterial activities against Cutibacterium acnes. Total phenolic compounds and total flavonoids in B.flabellifer L. male flower ethanolic extract were determined by the Folin–Ciocalteu method and aluminum chloride colorimetric assay, respectively. Active substances in the extract and their quantities were analyzed by liquid chromatography and mass spectrometry (LC–MS/MS). The antioxidant evaluation was carried out using DPPH, ABTS free radical scavenging assays, and FRAP assay. C. acnes inhibitory activity was performed by the broth microdilution method. Anti-inflammatory activity was determined by the protein denaturation assay. In addition, gel containing different amounts of B.flabellifer L. male flower extract was formulated. The physical stability of the gel was observed by measuring viscosity and pH after six heating and cooling cycles, as well as 1-month storage at 4, 30, and 45 °C. The total phenolic content in the extract was 268.30 ± 12.84 mg gallic acid equivalent/g crude dry extract. The total flavonoid contents in the extract were 1886.38 ± 55.86 mg quercetin equivalent/g extract and 2884.88 ± 128.98 mg EGCG equivalent/g extract, respectively. The LC–MS/MS analysis revealed the presence of gallic acid, coumarin, and quercetin and the concentrations of quercetin, coumarin, and gallic acid in B. flabellifer male flower ethanolic extract were 0.912, 0.021, and 1.610 µg/mL, respectively. DPPH and ABTS antioxidant assays indicated that the B.flabellifer L. male flower extract had IC50 values of 31.54 ± 0.43 and 164.5 ± 14.3 µg/mL, respectively. FRAP assay revealed that the B.flabellifer male flower extract had high ferric ion reducing power. The extract was able to inhibit C.acnes bacteria with a minimum inhibitory concentration (MIC) of 250 mg/mL. At 250 and 500 µg/mL, the extract demonstrated the highest anti-inflammatory activity. The gel containing 31.25% w/w and 62.5% w/w showed good physical stability after six heating and cooling cycles, as well as 1-month storage.

Development of Jelly Loaded with Nanogel Containing Natural L-Dopa from Mucuna pruriens Seed Extract for Neuroprotection in Parkinson’s Disease

“…Total phenolic content in M. pruriens spray dried seed extract was determined by the Folin and Ciocalteu reaction [ 15 ]. Gallic acid and M. pruriens seed extract were dissolved in deionized water at concentrations of 3.9–2000 µg/mL.…”

“…The total flavonoid content in spray dried M. pruriens extract was determined by the aluminum chloride colorimetric method [ 15 ]. Quercetin, epigallocatechin (EGCG), and extract solution at concentrations of 3.9–2000 µg/mL (100 µL/well) were added with NaNO 2 (5%, 30 µL) in 96-well plates.…”

“…The DPPH free-radical scavenging capacity of M. pruriens seed extract was determined and compared to gallic acid [ 15 ]. Gallic acid standard solution and M. pruriens seed extract sample solution were prepared by dissolving compound and extract in deionized water at concentrations ranging from 3.9 to 2000 µg/mL.…”

“…A FRAP reagent was prepared by mixing an acetate buffer (300 mM, pH 3.6) with 10 mM TPTZ in 40 mM HCl, and 20 mM FeCl 3 at 10:1:1 ( v / v ) ratio. The gallic acid and sample solutions (20 µL) were reacted with the FRAP reagent (180 µL) for 30 min at 37 °C [ 15 ]. The absorbance was then measured at a wavelength of 595 nm.…”

Emulgels Containing Perilla frutescens Seed Oil, Moringa oleifera Seed Oil, and Mixed Seed Oil: Microemulsion and Safety Assessment

“…They were stored in these temperatures for 48 h, which accounted for one cycle. The test was performed for 6 consecutive cycles in total [19]. The size, PDI, zeta potential value, and pH values of microemulsions were determined every two cycles.…”