Phytochemical Screening and Antibacterial Activity of Ocimum Gratissimum L. (Lamiaceae) Leaf Extract Against Pathogens Causing Ear Infections


Phytochemical screening and antibacterial activity of Ocimum gratissimum L. (Lamiaceae) leaf extract against pathogens causing ear infections.

Aderonke Ayinke Adepoju-Bello, *Bamisaye Olaofe Oyawaluja and Damilola Ilori.

  1. Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Lagos Nigeria.
  2. Department of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka, 410001, Enugu State, Nigeria.
  3. Department of Pharmacognosy and Traditional Medicine, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria


Keywords; Ocimum gratissimum, pathogens, ear infections, antibacterial activity, phytochemical screening.





*Corresponding author:

DOI: 10.48245/tnpr-2734391.2023.4.204

Page No: 71-80
Volume:4, Issue 2, 2023
Trends in Natural Products Research
Copy Right: NAPREG


Medicinal plants have been used traditionally for curative purposes due to their diverse array of constituents. Ocimum gratissimum is acclaimed for its forkloric use in the management of headaches, diarrhea, pneumonia, infections etc.
This investigation aimed to determine the phytochemical constituents and antimicrobial activity of the aqueous-ethanolic extract of O. gratissimum. Qualitative phytochemical analysis was done and the quantification carried out using Ultraviolet-visible (UV) spectrophotometry method. Qualitative analysis involved the detection of alkaloids, tannins, quinones, coumarins, flavonoids, cardiac glycosides, saponins, terpenoids and phenolic compounds in the extract, while the quantitative analysis involved quantification of both flavonoid and phenol using the UV-spectrophotometer. The antimicrobial activity of the extract was determined using agar disk diffusion method for activity against Proteus mirabilis, Streptococcus pneumonia, Pseudomonas aeruginosa, and Staphylococcus aureus. Determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the extract were also done. Phytochemicals present include both hydrolyzed and condensed tannins, alkaloids, flavonoids, phenolics, saponins, cardiac glycosides, terpenoids and coumarins but not quinones. The total content of flavonoids and phenols present were 11.27 mg/g and 117.08 mg/g respectively. The extract presented activities against P. mirabilis, S. pneumonia and P. aeruginosa while a higher activity was observed against S. aureus. The extract contained a number of phytochemicals which singly or synergistically, could be responsible for most of the extract’s pharmacological activities. The extract of O. gratissimum showed antimicrobial activity against common pathogens causing ear infections and this further affirms the ethnobotanical use of the plant for treating ear infection