Kanchana Ekanayake and Chamari M Hettiarachchi*

Department of Chemistry, Faculty of Science, University of Colombo, Sri Lanka

*Corresponding Author: Chamari M Hettiarachchi, Department of Chemistry, Faculty of Science, University of Colombo, Sri Lanka.

Received: December 31, 2021; Published: February 23, 2022

Abstract

The discovery of novel antimicrobial agents has become one of the most important aspects of today's world. Sri Lanka has a diverse collection of medicinal plants that play an important therapeutic role for many decades. This study was designed to identify such indigenous plants from the Rubiaceae family and investigate their unknown antimicrobial activities. Based on their ayurvedic value and the scarcity of scientific research, five Rubiaceae plant species (Knoxia zeylanica, Ophiorrhiza mungos, Oldenlandia herbacea, Oldenlandia herbacea, Wendlandia bicuspidata, and Morinda umbellata) were selected. The antifungal activity of crude plant extracts was tested using the poison food technique against Aspergillus spp., Rhizopus spp., and Penicillium spp. fungal strains. Out of three fungal strains, Penicillium spp. showed the highest susceptibility to crude extracts; K. zeylanica (root), O. mungos (whole plant), and O. herbacea (stem and leaves). At a concentration of 2 mg/ml, the crude extract of O. mungos (whole plant) inhibited (98.56 %) the growth of Aspergillus spp., indicating the presence of strong antifungal compound/s in O. mungos species. The agar well diffusion method was used to conduct an antibacterial assay against two Gram-positive bacteria, Staphylococcus aureus (ATCC 25928), Bacillus cereus (ATCC 11778), and two Gram-negative bacteria, Pseudomonas aeruginosa (ATCC 9027) and Escherichia coli (ATCC 35218). The crude extract (1mg per well) of K. zeylanica (root) demonstrated the highest antibacterial activity against B. cereus (16.2 ± 0.3 mm) and S. aureus (16.9 ± 0.3 mm). According to the findings of this study, K. zeylanica and O. mungos could be potential candidate plants for further research to isolate both anti-bacterial and antifungal compounds.

Keywords: Medicinal Plants; Rubiaceae; Anti-fungal; Anti-bacterial; Ayurvedic Medicine

References

1. Czaplewski L., et al. “Alternatives to antibiotics-a pipeline portfolio review”. The Lancet Infectious Diseases2 (2016): 239-251.
2. Infectious Diseases Society of America (IDSA). “Combating Antimicrobial Resistance: Policy Recommendations to Save Lives”. Clinical Infectious Diseases5 (2011): S397-S428.
3. Ventola C. "The Antibiotic Resistance Crisis: Part 1: Causes And Threats". PubMed Central (PMC). N.p., 40.4 (2015): 277–283.
4. Mohotti Supun., et al. “Screening for bioactive secondary metabolites in Sri Lankan medicinal plants by microfractionation and targeted isolation of antimicrobial flavonoids from Derris scandens”. Journal of Ethnopharmacology 246 (2020).
5. Karou Simplice D., et al. "Sub-Saharan Rubiaceae: A Review Of Their Traditional Uses, Phytochemistry And Biological Activities”. Pakistan Journal of Biological Sciences3 (2011): 149-169.
6. Silva LB., et al. “A Review of Work Carried out on Indigenous Plants”. Medical Research Institute, Colombo 08, Ceylon. Government Press, Colombo, Ceylon. (1967).
7. Dharsana J N and Molly Mathew. "Preliminary sceening of Anti inflammatory and Antioxidant activity of Morinda umbellata”. International Journal of Pharmacy and Life Sciences8 (2014).
8. CT Chiou., et al. “Isolation and cytotoxic effect of anthraquinones from Morinda umbellata”. Planta Medica 13 (2014): 1113-1117.
9. Danlami Uzama and Rabiu Lawal Danhalilu. "Antibacterial, proximate and antioxidant studies of Oldenlandia Herbacea extract”. Journal of Pharmaceutical and Biological Sciences2 (2015): 61.
10. Krishnakumar G., et al. “Ophiorrhiza, a Promising Herbaceous Source of the Anticancer Compound Camptothecin”. Plant Science Today2 (2020): 40-50.
11. Jayasinghe ULB., et al. “Antimicrobial Activity of Some Sri Lankan Rubiaceae and Meliaceae”. Fitoterapia 5 (2002): 424-27.
12. de Silva L B., et al. “An Iridoid Glycoside from Wendlandia Bicuspidata”. Journal of Natural Products6 (1987): 1184-1184.
13. Jorgensen James H and Mary Jane Ferraro. “Antimicrobial Susceptibility Testing: A Review of General Principles and Contemporary Practices”. Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America 11 (2009): 1749-1755.
14. Balouiri Mounyr., et al. “Methods for in Vitro Evaluating Antimicrobial Activity: A Review”. Journal of Pharmaceutical Analysis2 (2016): 71-79.
15. Mondall N K., et al. “Antifungal Activities and Chemical Characterization of Neem Leaf Extracts on the Growth of Some Selected Fungal Species in Vitro Culture Medium”. World Bank assisted National Agricultural Research Project (NARP) - University of Port Harcourt, July (2009).
16. “Alkaloid extraction document by Osmium”.
17. Belay A., et al. “Measurement of caffeine in coffee beans with UV/vis spectrometer”. Food Chemistry1 (2018): 310-315.
18. Sarker D., et al. “Natural Products Isolation”. 2^nd Edition (Methods in Biotechnology, Vol. 20). Humana Press Inc., Totowa, NJ. Journal of Natural Products. American Chemical Society, Apr. 70.4 (2007): 712-712.
19. Green RJ. “Antioxidant activity of Peanut plant tissues”. Master thesis, North Carolina state university, USA (2004).

Citation

Citation: Kanchana Ekanayake and Chamari M Hettiarachchi. “Determination of the Antimicrobial Activity of Selected Medicinal Plant Species in the Rubiaceae Family". Acta Scientific Microbiology 5.3 (2022): 60-67.

Copyright

Copyright: © 2022 Kanchana Ekanayake and Chamari M Hettiarachchi. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.