Volatile profiling coupled with multivariate analysis, antiproliferative and anti-inflammatory activities of rhizome essential oil of four Hedychium species from India.

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Hedychium of family Zingiberaceae comprises several perennial rhizomatous species widely used in perfumery and traditional folk medicine to treat diseases related to asthma, diarrhoea, nausea, stomach disorders, inflammation and tumours. Several species of Hedychium have remained under-explored with respect to their chemical composition and biological activities.

AIM OF THE STUDY

The current research aimed to explore the chemical composition and evaluate the antiproliferative and anti-inflammatory activities of rhizome essential oil from four Hedychium species (H. coccineum, H. gardnerianum, H. greenii and H. griffithianum).

MATERIALS AND METHODS

Compound identification was accomplished using a Clarus 580 gas chromatography system in conjunction with mass spectrometry (GC-MS). The multivariate data statistics using chemometrics (PCA, PLS-DA, sPLS-DA) and cluster analysis (Dendrogram, Heat maps, K-means) were used to compare the similarity and relationship among Hedychium metabolomes. MTT assay was employed to visualize the antiproliferative property against MCF7, HepG2 and PC3 cancerous cell lines. The toxicity of essential oils was determined using 3T3-L1 non-tumorigenic/normal cells. Lipopolysaccharide (LPS)-induced RAW 264.7 cells were used to investigate the anti-inflammatory properties of Hedychium essential oils by measuring the production of nitric oxide (NO) using the Griess reagent method. Furthermore, the levels of prostaglandin (PGE) and pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) was assessed using the ELISA technique.

RESULTS

In total, 82 compounds were identified in four targeted species of Hedychium from which 1,8-cineole (52.71%), β-pinene (32.83%), α-pinene (19.62%), humulene epoxide II (19.86%) and humulene epoxide I (19.10%) were the major constituents. Monoterpenes (8.5-59.9%) and sesquiterpenes (2.87-54.11%) were the two class of compounds, found as the most prevalent in the extracted essential oils. The multivariate analysis classified the four Hedychium species into three different clusters. Hedychium essential oils exhibited potent antiproliferative activity against MCF7, HepG2 and PC3 cancer cell lines with IC values less than 150 μg/mL where H. gardnerianum exhibited the highest selective cytotoxicity against human breast and prostate adenocarcinoma cells with an IC value of 44.04 ± 1.07 μg/mL and 56.11 ± 1.44 μg/mL, respectively. The essential oils on normal (3T3-L1) cells displayed no toxicity with higher IC values thereby concluding as safe to use for normal human health without causing any side effects. Besides, the essential oils at 100 μg/mL concentration revealed remarkable anti-inflammatory activity in LPS-activated RAW 264.7 murine macrophages by inhibiting the production of inflammatory mediators, with H. greenii exhibiting the maximum anti-inflammation response by significantly suppressing the levels of NO (84%), PGE (87%), TNF-α (94.3%), IL-6 (95%) and IL-1β (85%) as compared to LPS treated group.

CONCLUSION

The present findings revealed that the Hedychium species traditionally used in therapeutics could be a potential source of active compounds with antiproliferative and anti-inflammatory properties.