Evaluation of the constituent compounds, antioxidant, anticancer, and antimicrobial potential of Prangos ferulacea plant extract and its effect on Listeria monocytogenes virulence gene expression

Abstract

Prangos ferulacea plant is very popular in Iran due to its unique properties in treating diseases and its special flavor. To check the characteristics of this plant, first, its extract was extracted using the maceration method. Its chemical composition was investigated using high-performance liquid chromatography (HPLC) that p-coumaric was identified as its main compound, and Fourier-transform infrared spectroscopy (FTIR) showed the presence of functional groups related to phenolic, flavonoid, tannins, and carboxylic acids such as caffeic acid and coumaric acid composition. Total phenol content (TPC), total flavonoid content (TFC), and beta-carotene were equal to 202.04 ± 5.46 mg gallic acid equivalent (GAE)/g dry weight, 1,909.46 ± 13 μg quercetin (QE)/g of dry weight, and 2.91 mg/100 g. The antioxidant property of the extract was evaluated using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) free radical scavenging and ferric reducing antioxidant power assay (FRAP). According to the IC50 obtained for DDPH (274 ± 7.2 μg/mL) and ABTS (120.45 ± 9.6 μg/mL) and FRAP values [1.92 ± 0.05 μg ascorbic acid equivalent (AAE)/g of extract], this extract had high antioxidant properties. Cytotoxicity was evaluated against the survival of HT 29 cells that IC50 was 82.15 ± 0.02 μg/mL. The antimicrobial property of the extract was calculated using disk diffusion agar (DDA), well diffusion agar (WDA), minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). Listeria monocytogenes has the highest sensitivity to this extract and inhibition zone based on DDA and WDA method and with an MIC and MBC equal to 16 and 128 mg/mL has the least resistance. The morphology change of L. monocytogenes strain was proved through scanning electron microscope (SEM) and confocal laser scanning microscopy (CLSM). The extract caused a significant reduction in the transcription of genes involved in the film formation ability of L. monocytogenes. The obtained results fully prove the very practical and pragmatic characteristics of P. ferulacea.

Keywords: HT 29 cells; Jashir; Listeria monocytogenes; confocal laser scanning microscopy; gene expression.

Figure 1

FTIR spectrum of Prangos ferulacea extract.

Figure 2

Determination of radical scavenging activity (RSA) percentage of Prangos ferulacea extract on (A) DPPH, (B) ABTS, and (C) FRAP radicals. Letters a–e in the (A, B) indicate the difference between different concentrations in an antioxidant and in (C) a–c indicate difference between different antioxidants.

Figure 3

Cytotoxic effect of various concentrations of Prangos ferulacea extract on survival of HT29 cell line.

Figure 4

Average IZ (mm) of Prangos ferulacea aqueous extract against pathogenic bacteria, based on DDA method [Different letters (a–e) in each strain show significant difference at p < 0.05]. Different letters (a–e) in each strain show significant difference at p < 0.05.

Figure 5

Average IZ (mm) of Prangos ferulacea aqueous extract against pathogenic bacteria, based on WDA method [Different letters (a–d) in each strain show significant difference at p < 0.05]. Different letters (a–d) in each strain show significant difference at p < 0.05.

Figure 6

SEM images of L. monocytogenes control (A) and L. monocytogenes treated with extract (B).

Figure 7

Confocal laser scanning microscopy (CLSM) images of L. monocytogenes control (A) and L. monocytogenes treated with extract (B).

Figure 8

Effects of extract on the transcription of L. monocytogenes biofilm- and virulence-associated genes. Bars represent the standard deviation (n = 3).