Scirpusin B isolated from Passiflora edulis Var. flavicarpa attenuates carbohydrate digestive enzymes, pathogenic bacteria and oral squamous cell carcinoma

Abstract

Passiflora edulis Var. flavicarpa (passion fruit) generates vast waste (60-70%) in the form of peel and seed after the juice extraction. The study aimed to isolate Scirpusin B (SB) from passion fruit (PF) seed waste collected from Northeast India and to analyse its anti-radical, antibacterial, anti-diabetic, and anti-oral cancer activities. Scirpusin B was isolated following hydro-alcoholic extraction, fractionation, and column chromatography. The isolated fraction was further identified through NMR and mass spectroscopy. SB exhibited significant antiradical activity against six standard antioxidant compounds, indicating its commercial application. SB inhibited α-amylase (IC₅₀ Value: 76.38 ± 0.25 µg/mL) and α-glucosidase digestive enzymes (IC₅₀ Value: 2.32 ± 0.04 µg/mL), signifying its antidiabetic properties. In addition, SB showed profound antibacterial activity against eight gram-positive and gram-negative bacteria reported for the first time. Furthermore, SB inhibited SAS and TTN oral cancer cell proliferation up to 95% and 83%, respectively. SB significantly inhibited colonies of SAS and TTn cells in the clonogenic assay, attributing to its anticancer properties. The PI-FACS assay confirmed the ability of SB (75 µM) to kill SAS and TTn cells by 40.26 and 44.3% in 72 h. The mechanism of SB inhibiting oral cancer cell proliferation was understood through western blot analysis, where SB significantly suppressed different cancer hallmark proteins, such as TNF-α, survivin, COX-2, cyclin D1, and VEGF-A. The present study suggests that SB isolated from PF seed can add noteworthy value to the waste biomass for various industrial and medical applications.

Supplementary information: The online version contains supplementary material available at 10.1007/s13205-023-03876-6.

Keywords: Antibacterial agent; Northeast India; Oral squamous cell carcinoma; Passiflora edulis Var. flavicarpa seed; Preparative HPLC; Scirpusin B.

Fig. 1

Scirpusin B from yellow passion fruit seed

Fig. 2

Schematic diagram of extraction and fractionation of passion fruit seed. The de fatted passion fruit seed was subjected to hydro-methanolic extraction and further followed by fraction using hexane, dichloromethane, ethyl acetate and butanol. The amounts of different passion fruit fractioned extracts are presented in this table

Fig. 3

Zone of Inhibition study of Scirpusin B on different gram negative and gram positive bacteria. Control (C) and different concentrations of scirpusin B are represented as 1 (2.5 mg/mL), 2 (5 mg/mL) and 3 (10 mg/mL) inside the images Different gram negative bacteria used for the study are a E. Coli, b Klebsiella pneumonia, c Enterobacter aerogenes and d Pseudomonas aeruginosa. Different gram positive bacteria used for the study are e Staphylococcus aureus, f Bacillus subtilis, g Staphylococcus epidermidis and h Micrococcus luteus

Fig. 4

Inhibition of cell proliferation by scirpusin B on SAS (a) and TTn (a) oral squamous carcinoma cell. All the experiments carried out are presented as mean ± SD of three individual experiments in triplicate

Fig. 5

Inhibition of clonogenic potential of scirpusin B on SAS (a) and TTn (b) cell lines. The dose versus survival fraction graph is presented adjacent to the respective SAS and TTn clonogenic images. All the experiments carried out are presented as mean ± SD of three individual experiments in triplicate. p < 0.05 vs control are reported for clonogenic assay

Fig. 6

Scirpusin B induced cell death assay by PI-FACS on SAS (a) and TTn (b) cells. Cell death percentage by different concentrations of scirpusin B obtained from PI-FACS is presented in the adjacent graphs. All the experiments carried out are presented as mean ± SD of three individual experiments in triplicate. p < 0.05 vs control are reported for PI-FACS analysis

Fig. 7

Inhibition of oral cancer hallmark proteins by scirpusin B on SAS and TTn cells by western blot analysis. Inhibition of different hallmark proteins in SAS cells by SB is presented from (a) to (e) (a; SAS–TNFα, b; SAS–VGFA-A, c; SAS–COX2, d; SAS-Cyclin D1 and e; SAS-Survivin). Similarly, Inhibition of different hallmark proteins in TTn cells by SB is presented from (f) to (j) (f; TTn-TNFα, g; TTn-VGFA-A, h; TTn-COX2, i; TTn-Cyclin D1 and j; TTn-Survivin)