Vol. 11, Issue 6 (2022)

Author(s):
Niteeshkumar, Srinivasappa KN, Venugopala Reddy M and Tamil Vendan K

Abstract:
Curcuma caesia Roxb. is an important, lesser known, non-conventional medicinal plant belonging to Zingiberaceae family. The eight genotypes selected were GKM-1, GKM-2, GKB-3, GKB-4, GKJ-5, GMV-6, GKT-29 and GKK-30 were collected from different regions as presented in (Table 1). The Rhizomes of black turmeric genotypes were extracted with methanol at room temperature for 18 h. Preliminary phytochemical analysis revealed the presence of tannins, flavonoid and phenol. The highest phenol GMV-6 (1.46 mg^-1g), tannin GKT-29 (0.69 mg^-1g) and flavonoid GMV-6 (1.64 mg^-1g) was recorded. The bioactive compounds of Curcuma caesia Roxb have been evaluated using GC-MS. Totally 19 major compounds were identified from eight genotypes. The major constituents were identified in the methanolic rhizome extracts were Curcumenol in GKM-1(20.35%), GKB-3(12.96%), GKB-4(15.67%) and in GKT-29(16.17%), Curcumenone in GKM-1(16.07%), GKM-2(25.03%), GKB-3(29.30%) and in GKT-29(22.25%), Epicurzerenone in GKM-1(12.93%) and GKM-2(21.82%), 9-12, Octadecadionic acid in GKM-1(5.54%), GKB-3(2.81%) and in GKB-4(3.59%), 2-Bornanone in GKM-2(4.38%) and in GKB-3(5.38%), 4H-Pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl- in GKB-3(8.91%), GKB-4(24.44%), GKJ-5(19.82%) and GKT-29(9.88%), Isoborneol in GKM-2(1.54%) and GKB-3(3.67%) and Eucalyptol in GKM-2(1.17%). The research findings have shown that the rhizome of C. caesia is extensively rich in secondary metabolites. The extracts were assessed for their potential antibacterial activity against Gram positive and Gram negative bacteria viz., Bacillus cereus, Bacillus subtilis, Streptococcus agalactiae, Escherichia coli, Pseudomonas aeruginosa and Shigella flexneri. The rhizome extracts of black turmeric genotypes exhibit positive results against the Gram positive bacteria.