Phytochemical Properties and Effect of Temperature on Proximate and Mineral Composition of Curcuma longa Linn. Rhizomes Ethanolic Extract

Aims: To investigate the phytochemical property of fresh Curcuma longa rhizomes and the effect of temperature on proximate and mineral composition of dried C. longa rhizomes.

Study Design: Activity directed antioxidant and phenolic content investigation of C. longa rhizomes using in vitro methods.

Place and Duration of the Study: Medicinal Plants Section, Bioresources Development Centre, Ogbomoso, Nigeria between August and October, 2016.

Methodology: Fresh C. longa rhizomes was washed and divided into five portions (A-E). Portion A-D was dried (at room temperature, 40°C, 50°C and 60°C respectively) and used for proximate and mineral composition investigation while portion E (fresh C. longa rhizomes) was used for screening the phytochemical composition of the rhizomes.

Results: The result of this study showed the presence of alkaloids, tannin, saponin, phenol, cardiac glycosides, phlobatannin, flavonoids, anthraquinones, steroids, terpenes and cardenolides in C. longa rhizome. Also there was a significant (P<0.05) increase in crude protein, crude fat and ash at 50°C and a significant (P<0.05) increase in crude fat and carbohydrate at 60°C when compared with room temperature and 40°C. Also, at 40°C there was a significant (P<0.05) decrease in sodium, calcium and phosphorus when compared with room temperature, while at 50°C there was a significant (P<0.05) increase in sodium, potassium, magnesium, calcium, phosphorous and iron when compared with room temperature and 40°C.

Conclusion: In conclusion, the use of C. longa rhizomes in ethno-medicine for the treatment/management of a lot of diseases may be due to the presence of some phytochemicals, nutrients and minerals found in the plant and also, the concentration of these nutrients may be affected by temperature.