Exploring the Antibacterial and Haemo-Modulatory Effects of Aqueous Hibiscus sabdariffa Leaf Extract on Escherichia coli

Abstract

Hibiscus sabdariffa is commonly used for local beverages.  This research was undertaken to investigate the in vivo antibacterial properties as well as the immunomodulatory activities of aqueous Hibiscus sabdariffa leaf extract against Escherichia coli ATCC29214 in albino rats. Three groups of five rats each were used for this study. Groups B and C were orally given E. coli by gavage to gastrointestinal tract infection. Rats in Group C were treated with the plant extract while those in Groups A were given commercially prepared feed and clean water ad libitum. Stool samples obtained from the various groups were analyzed using standard microbiological protocols. Similarly, blood samples were also obtained from rats in the various groups for haematological analysis. The mean heterotrophic bacterial counts in the untreated group ranged from 64 x 10⁶ cfu/g to 66 x 10⁶ cfu/g from day one to three, while it ranged from 27 x 10⁶ cfu/g to 6.0 x 10⁶ cfu/g for treated rats respectively. Haematological parameters assayed varied between infected rats exposed to aqueous H. sabdariffa leaf extract and the unexposed group. Haemoglobin (g/dl) ranged from 14.7g/dl in the control through 13g/dl in the untreated to 15.3g/dl in the treated group. There was also a significant increase in procalcitonin levels in the untreated group was 577,000 (µl) 10³ compared to 481,000 (µl) 10³ and 471,000 (µl) 10³ in the control and treated respectively. PCV level was highest in the treated group (56%). The RBC count remained in treated and control groups were 7.3 and 7.1 (10¹²/L) respectively. While that of the untreated group was 6.1(10¹²/L). WBC count was 11,900 in the control group, 20,800 in infected rats and 10,300 in the treated group. The research shows that the aqueous H. sabdariffa leaf extract has potential in vivo antibacterial activity as well as potent immunomodulatory actions critical for combating E. coli related infection.