UNRAVELLING THE IDENTITY OF BLACK GINGER AND BLACK TURMERIC IN THE MALAYSIAN HERBAL MARKET

Abstract

The Zingiberaceae family has long been utilised in Asia for medicinal, culinary, and cosmetic purposes. However, the identification of specific species within this family, such as black ginger and black turmeric, remains challenging in the Malaysian herbal market due to morphological similarities and the lack of standardised identification methods. This study aims to address these challenges by accurately identifying black ginger and black turmeric through comprehensive morphological and chemical analyses. A total of 43 samples of fresh rhizomes and plantlets were collected from nurseries and online platforms across Peninsular Malaysia. The samples were categorized into three groups: Group 1–black ginger (kunyit hitam Thai/halia hitam), Group 2–black turmeric (kunyit hitam India), and Group 3–black turmeric/pink and blue ginger (temu hitam/temu ireng). Morphological characterisation revealed distinct differences in rhizome shape, colour, odour, leaf structure, and inflorescences among the groups. Chemical analyses using HPLC, HPTLC, and FTIR further differentiated the species, with Group 1 displaying a chemical profile consistent with the authenticated K. parviflora, marked by the presence of 5,7-dimethoxy flavone. Groups 2 and 3, although morphologically similar, were distinguishable through specific rhizome and leaf characteristics and were chemically similar to the authenticated C. caesia and C. aeruginosa, respectively. These findings underscore the importance of both morphological and chemical profiling in the accurate identification of these species, which is crucial for ensuring the authenticity and quality of herbal products in the Malaysian market. This study provides a foundation for improved species authentication and contributes to the standardisation of the herbal industry.