Evaluation of Phytochemical Content and Antibacterial Activity of Zingiber officinale and Curcuma longa Synergistic Combinations (Peeled and Unpeeled)

Adesipe, T.I., Volume 3 Issue 2, December 2022 Pages 1-9, Published: 2022-12-09

Abstract

This study compared the phytochemical contents and the antibacterial activities of peeled and unpeeled blended mix juice of Zingiber officinale and Curcuma longa rhizome against Bacillus subtilis and Staphylococcus aureus (Gram positive bacteria).The results of the phytochemical screening indicated the presence of phytochemicals including flavonoid, tannins, phenol, reducing sugar, saponin, steroids and cardiac glycosides, most of which have been linked to antibacterial activity, in both combinations (peeled and unpeeled). However, terpenoid, which is also a powerful antibacterial compound, was present only in the unpeeled blend mix whereas the result for the quantitative analysis showed that the quantity of phytochemicals in peeled and unpeeled juice blend were: tannin (23.54 ± 0.20 mg/100 g and 22.6 ± 0.48 mg/100 g), flavonoid (40.84 ± 0.14 mg/100 g and 41.78 ± 0.26 mg/100 g), and phenol (32.83±0.28 mg/100 g and 31.07 ±0.67 mg/100 g), reducing sugar (29.54 ± 0.23 mg/100 g and 31.54 ±0.47 mg/100 g ), saponin (40.48 ± 0.14 mg/100 g and 41.78 ±0.26 mg/100 g),steroids (27.43 ± 0.16 mg/100 g and 28.42 ± 0.35 mg/100 g) and cardiac glycosides (29.54 ± 0.21 mg/100 g and 30.11± 0.67 mg/100 g) respectively. The result of the antibacterial activity revealed that the peeled combination had antibacterial activity against B. subtilis with a zone of inhibition of 20 mm and none against S. aureus, while the unpeeled combination had antibacterial effect on S. aureus with a zone of inhibition of 20 mm and none against B. subtilis. In comparison to Levofloxacin, which showed zones of inhibition of 20 mm and 17 mm against S. aureus and B. subtilis, the peeled and unpeeled blended extracts of Z. officinale and C. longa rhizome combination showed antibacterial effectiveness. This result demonstrated that the quality and quantity of phytochemicals present in the combined rhizomes of ginger and turmeric can be affected by the presence or absence of peels and consequently on their therapeutic action.