Exploration of the Species-specific Dna Markers Based on the Complete Chloroplast Genome for Discriminating Curcuma Comosa Roxb. From Curcuma Latifolia Roscoe and Other Related Species

Members of the Curcuma genus are among the most commonly used rhizomatous herbs worldwide. There are two species of Curcuma referred to as “Wan Chak Motluk” in Thai, C. comosa Roxb. and C. latifolia Roscoe, and their herbal materials are often confused. C. comosa is widely used as a traditional herbal remedy for its phytoestrogenic activity, but its morphology is highly similar to that of C. latifolia, which contains a compound that causes hepatotoxicity. In this study, the complete chloroplast (cp) genomes of these species were determined for the first time using Illumina sequencing. Our results showed that their cp genomes were 162,272 bp (C. comosa) and 162,289 bp (C. latifolia) in length. A total of 133 unique genes were identified, including 87 protein-coding genes, 38 tRNA genes and 8 rRNA genes. Comparative analyses with other species of Curcuma indicated high similarity in gene content and structural organization. The analyses also reveal variable hotspots in the genomes at ndhA, trnT-trnL, and ndhC-trnV that can serve as species-specific nucleotide barcodes. Indeed, mislabeling of these two species among samples sold at market was detected using these species-specific markers, indicating that cp genomes can provide more information for better elucidating and improving discriminatory power for species authentication.

Effects of Curcuma comosa Roxb. Extract on the Expression of CYP450s in Immortalized Hepatocyte-like Cells (imHC)

Hepatocytes are the most abundant liver cells that produce biotransformation enzymes, including phase I metabolism enzymes and cytochrome P450s (CYP450s). These enzymes are induced or suppressed by several drugs and chemicals. Here, immortalized hepatocyte-like cells (imHC) were applied as a novel hepatocyte to study the CYP450 enzyme expression induced by a Thai folk herb, Curcuma comosa Roxb. (C. comosa). The results demonstrated that the mRNA expression levels were dependent on cell cultivation conditions, the extract's concentration, and the duration of treatment. In the 3-day cultivation, 1 µg/mL C. comosa extract upregulated the mRNA expression levels of CYP1A1, CYP1A2, CYP2B6, CYP2C9, CYP2D6, CYP2E1 and CYP3A4 in imHC, after treatment for 48 h, which was comparable to the expression levels of those genes in HepG2 cells. In addition, C. comosa increased CYP3A4 protein expression in both imHC and HepG2 cells. Furthermore, 1 µg/mLC. comosa could neutralize erythromycin's inhibitory effect, a specific CYP3A4 inhibitor, on CYP3A4 enzyme activity. In conclusion, imHC exhibited several detoxification enzymes, and this cell could be used to replace hepatic carcinoma cells in hepatotoxic studies. The function of C. comosa as a CYP enzyme-inducing agent indicates a promising treatment for the prevention of drug-induced hepatotoxicity by activating detoxification enzymes.

Cytotoxic and Antiproliferative Effects of Diarylheptanoids Isolated from Curcuma comosa Rhizomes on Leukaemic Cells

Curcuma comosa belongs to the Zingiberaceae family. In this study, two natural compounds were isolated from C. comosa, and their structures were determined using nuclear magnetic resonance. The isolated compounds were identified as 7-(3,4-dihydroxyphenyl)-5-hydroxy-1-phenyl-(1E)-1-heptene (1) and trans-1,7-diphenyl-5-hydroxy-1-heptene (2). Compound 1 showed the strongest cytotoxicity effect against HL-60 cells, while its antioxidant and anti-inflammatory properties were stronger than those of compound 2. Compound 1 proved to be a potent antioxidant, compared to ascorbic acid. Neither compounds had any effect on red blood cell haemolysis. Furthermore, compound 1 significantly decreased Wilms’ tumour 1 protein expression and cell proliferation in KG-1a cells. Compound 1 decreased the WT1 protein levels in a time- and dose- dependent manner. Compound 1 suppressed cell cycle at the S phase. In conclusion, compound 1 has a promising chemotherapeutic potential against leukaemia.

Sesquiterpene from Myanmar Medicinal Plant (Curcuma comosa)

Curcuma comosa (Zingiberaceae) is widely grown in tropical and subtropical areas of Asia, like Thailand, Indonesia, Malaysia, and Myanmar. In Myanmar, the rhizome of Curcuma comosa is called Sa-nwin-ga, and local people had used it as a traditional medicine for stomach ache, diabetes mellitus, and hypertension. This species produces secondary metabolites of phenolic and nonphenolic groups. Phenolic groups like diarylheptanoids and flavonoids. While nonphenolics are terpenoids, especially sesqui- and monoterpenes. In this chapter, the group of sesquiterpene compounds from Curcuma comosa starts from the isolation technique, followed by the elucidation of the molecular structure, and their activity tests have been discussed.