The root dichloromethane and ethyl acetate extracts of
Acanthus pubescens
(Oliv.) Engl (ACANTHACEAE) exhibited weak antibacterial activity against
Staphylococcus aureus, Bacillus subtilis, Bacillus anthracis, Salmonella typhi, Streptococcus faecalis, Streptococcus agalactiae and
Pseudomonas aeruginosa, with MIC values ranging from 1.6-6.25 mg/ml. The two extracts also exhibited weak antifungal activity against
Candida albicans (MIC 6.25 mg/ml). Using the brine shrimps lethality test ethanol, ethyl acetate and aqueous extracts were virtually non-toxic to brine shrimp larvae, but the dichloromethane extract (LC
50 38.9 μg/ml) was mildly toxic. These results support the use of the plant in traditional medicine to treat gonorrhea, syphilis, gastroenteritis and pneumonia. Since the plant is used in combination with other plants it is difficult to make any final conclusions regarding safety and efficacy. Further work is needed to evaluate the activity of an extract made from a combination of the six plants.
