Error message

Deprecated function: The each() function is deprecated. This message will be suppressed on further calls in theme_biblio_custom() (line 367 of /home/phcogcommn/

Centella asiatica (L.) Urban Leaf Extracts Inhibit the Growth of Bacterial Triggers of Selected Autoimmune Inflammatory Diseases and Potentiate the Activity of Conventional Antibiotics


Pharmacognosy Communications,2020,10,3,119-129.
Published:July 2020
Type:Original Article

Centella asiatica (L.) Urban Leaf Extracts Inhibit the Growth of Bacterial Triggers of Selected Autoimmune Inflammatory Diseases and Potentiate the Activity of Conventional Antibiotics

Yan Zhang1, Zihao Yang1, Ian Edwin Cock1,2*

1School of Natural Sciences, Nathan Campus, Griffith University, Brisbane, AUSTRALIA.

2Environmental Futures Research Institute, Nathan Campus, Griffith University, Brisbane, Queensland, AUSTRALIA.


Introduction: An increase in antibiotic resistance and a corresponding decrease in antimicrobial discovery have directed researchers towards alternative therapies, including plant based medicines. However, synergistic combinations of plant extracts with conventional antibiotics may be a far more effective approach in overcoming resistance and potentiating the activity of antibiotics that are otherwise ineffective against resistant bacterial strains. Methods: The antibacterial activity of Centella asiatica (Gotu Kola) extracts was investigated by disc diffusion and quantified by liquid dilution and solid phase MIC assays. The extracts were also combined with a range of conventional antibiotics and tested against various microbial triggers of autoimmune diseases. The ΣFIC values obtained from these assays were used to determine the class of combinational effects and isobologram analysis was used to determine the ideal synergistic ratio(s). Toxicity was evaluated by Artemia nauplii mortality assays. Results: The methanolic extracts showed good inhibitory activity against several microbial triggers of autoimmune inflammatory diseases, whilst the chloroform and hexane extracts were also potent inhibitors of K. pneumoniae growth. Combinations of the C. asiatica extracts with conventional antibiotics were often substantially more effective in inhibiting bacterial growth. One synergistic and 10 additive interactions were noted. Notably, the methanolic extract restored significant growth inhibitory activity to chloramphenicol and tetracycline when tested in combination against K. pneumoniae. In contrast, two antagonistic interactions were noted for combinations containing gentamycin (against A. baylyi and S. pyogenes), indicating that those combinations should be avoided when treating infections caused by those bacteria. Conclusion: C. asiatica extracts have potential as inhibitors of bacterial triggers of selected autoimmune inflammatory diseases. Furthermore, extract components may also potentiate the activity of two antibiotics that are relatively ineffective alone. Isolation of these agents may be beneficial in drug design against several bacteria, including the microbial triggers of rheumatoid arthritis, ankylosing spondylitis and multiple sclerosis.

Founded:  In 2004, as the PHCOG.NET – a non-profit private organization dedicated to Natural Products Research leading to develop promising drugs. Our main mission is to make information on herbal drug research readily available in different formats to suit the individual needs.

Pharmacognosy Communications [Phcog Commn.] is a new quarterly journal published by Phcog.Net. It is a peer reviewed journal aiming to publish high quality original research articles, methods, techniques and evaluation reports, critical reviews, short communications, commentaries and editorials of all aspects of medicinal plant research. The journal is aimed at a broad readership, publishing articles on all aspects of pharmacognosy, and related fields. The journal aims to increase understanding of pharmacognosy as well as to direct and foster further research through the dissemination of scientific information by the  publication of manuscripts. The submission of original contributions in all areas of pharmacognosy are welcome.

The journal aims to cater the latest outstanding developments in the field of pharmacognosy and natural products and drug design covering but not limited to the following topics:

  • Pharmacognosy and pharmacognistic investigations
  • Research based ethnopharmacological evaluations
  • Biological evaluation of crude extracts, essential oils and pure isolates
  • Natural product discovery and evaluation
  • Mechanistic studies
  • Method and technique development and evaluation
  • Isolation, identification and structural elucidation of natural products
  • Synthesis and transformation studies

Distinctions:  The most widely read, cited, and known Pharmacognosy Communications and website is well browsed with all the articles published. More than 20,000 readers in nearly every country in the world each month

Aim and Scope | Editorial Board | Indexed & Abstracted | Instruction to Authors | Manuscript Submission & Charges

Subjects Covered : Natural Products, Pharmacognosy, Phytochemistry, Marine Pharmacognosy and Zoo Pharmacognosy
ISSN :2249-0159 (Print) ; 2249-0167 (Online) Frequency : Quarterly Rapid at a time publication (4 issues/year)

Indexed and Abstracted in : Chemical Abstracts, Excerpta Medica / EMBASE, Google Scholar, CABI Full Text, Ulrich’s International Periodical Directory, ProQuest, Journalseek & Genamics, PhcogBase, EBSCOHost, Academic Search Complete, Open J-Gate, SciACCESS.
Rapid publication: Average time from submission to first decision is 30 days and from acceptance to In Press online  publication is 45 days.
Open Access Journal: Phcog Commn. is an open access journal, which allows authors to fund their article to be open access from publication.