Alliums as Potential Antioxidants and Anticancer Agents

Abstract

The genus Allium plants, including onions, garlic, leeks, chives, and shallots, have long been recognized for their potential health benefits, particularly in oxidative and cancer prevention. Among them, onions and garlic have been extensively studied, unveiling promising biological activities that are indicative of their potential as potent antioxidant and anticancer agents. Research has revealed a rich repository of bioactive compounds in Allium species, highlighting their antioxidative properties and diverse mechanisms that target cancer cells. Compounds such as allicin, flavonoids, and organosulfur compounds (OSCs) exhibit notable antioxidant and anticancer properties, affecting apoptosis induction, cell cycle arrest, and the inhibition of tumor proliferation. Moreover, their antioxidant and anti-inflammatory attributes enhance their potential in cancer therapy. Studies exploring other Allium species beyond onions and garlic have revealed similar biological activities, suggesting a broad spectrum of natural products that could serve as promising candidates for developing novel anticancer treatments. Understanding the multifaceted potential of Allium plants will pave the way for innovative strategies in oxidative and cancer treatment and prevention, offering new avenues for pharmaceutical research and dietary interventions. Therefore, in this review, we compile an extensive analysis of the diversity of various Allium species, emphasizing their remarkable potential as effective agents.

Keywords: Allium; anticancer; antioxidants; bioactive compounds; edible.

Figure 1

IUCN Red List category of Allium species, depicting the percentage of species classified as critically endangered (CR), endangered (EN), vulnerable (VU), near threatened (NT), least concern (LC), and data-deficient (DD).

Figure 2

The major genebanks worldwide with Allium accessions.

Figure 3

Countries with total crop (a), Allium (b) accessions, accession-holding institute (c), species name provided to accession during the submission (d), and germplasm storage type (e) from the data accessed through Genesys on 30 December 2023.

Figure 4

Steroidal glycosides from A. jesdianum Boiss & Buhse. (a) (22S)-cholest-5-ene-1β,3β,16β,22-tetrol 1,16-di-O-β-d-glucopyranoside (1), (22S)-cholest-5-ene-1β,3β,16β,22-tetrol 1-O-α-l-rhamnopyranosyl 16-O-β-d-glucopyranoside (2). (b) (25R)-5α-spirostane-2α,3β-diol 3-O-{O-β-d-glucopyranosyl-(1→2)-O-[β-d-xylopyranosyl-(1→3)]-O-β-d-glucopyranosyl-(1→4)-β-d-galactopyranoside}(F-gitonin). (c) (25R)-5α-spirostane-2α,3β,6α-triol 3-O-{O-β-d-glucopyranosyl-(1→2)-O-[β-d-xylopyranosyl-(1→3)]-O-β-d-glucopyranosyl-(1→4)-β-d-galactopyranoside}.

Figure 5

Steroidal saponins of A. macrostemon Bunge. (a) 26-O-β-D-glucopyranosyl-5α-furost-25 (27)-ene-3β, 12β, 22, 26-tetraol-3-O-β-D-glucopyranosyl (1→2) [β-D-glucopyranosyl (1→3)]-β-D-glucopyranosyl (1→4)-β-D-galactopyranoside. (b) 26-O-β-D-glucopyranosyl-5β-furost-20 (22)-25 (27)-dien-3β, 12β, 26-triol-3-O-β-D-glucopyranosyl (1→2)-β-D-galactopyranoside. (c) Macrostemonoside A of A. macrostemon.