Investigation of antioxidant and anticancer potential of fucoidan (in-vitro &in-silico) from brown seaweed Padina boergesenii

Abstract

The present study was aimed to evaluate the antioxidant, anticancer activity and in-silico analysis of fucoidan extracted from the brown seaweed Padina boergesenii (SF-PB). The overall dry mass of the isolated SF-PB and sulphate residues was found to be 4.9 ± 0.12 % and 17.72 ± 0.25 % respectively. The Fourier Transform Infrared Spectroscopy (FTIR), X-Ray diffraction analysis (XRD), Nuclear Magnetic Resonance (NMR) Spectroscopy, High-performance liquid chromatography (HPLC), and Electrospray Ionisation Mass Spectrometry (ESI-MS) are used to further characterize the fucoidan. The antioxidant assays results showed significant antioxidant activity in a dose-dependent manner. The highest antioxidant activity was observed in the 2,2-diphenyl-1-picrylhydrazyl (DPPH)-76.75 %, Reducing power-66.55 %, 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) -(ABTS)-70.55 %, Hydrogen peroxide (H2O2)-59.9 %, Nitric oxide, and Total antioxidant scavenging (TAC) -68.92 % at 1000 μg/mL with an IC-50 value of 55.62, 59.70, 57.43, 64.40, 61.88 and 60.73 respectively. The cytotoxic effect of SF-PB on human cervical carcinoma cells (HeLa) demonstrated a significant percentage of inhibition 54 % at 40 μg/mL. Fucoidan IC 50 value against cancer cells was determined and found to be 38 μg/mL. Further, the apoptotic staining analysis depicted that fucoidan acts on HeLa cells and induces apoptosis through nuclear fragmentation, inhibition of the cell cycle at the G1 phase, and also with a high level of ROS production. Furthermore, Mesocyclops leuckarti copepod showed no toxicity when treatsed with fucoidans at a concentration of 250 μg/mL (100 % survival), demonstrating that fucoidan are not hazardous and are environmentally benign. In a docking investigation, fucoidan demonstrated the highest binding affinity against apoptotic proteins. Fucoidan may be an alternative for patients with cervical cancer. The findings showed that isolated fucoidan from P. boergesenii has substantial antioxidant and anticancer effects.