Background: Herbal practitioners in the Eastern Cape of South Africa use valerian root (
Valeriana capensis
, Valerianaceae) to manage pains,
arthritis and inflammation. The herb prepared from this plant was studied to determine the chemical composition of its essential oil, carried out
phytochemical screening and biological activities on its infusion extract as used by the herbal practitioner.
Materials and Methods: Essential oil of
Valerian root was obtained by hydrodistillation and subjected to chemical analyses. Infusion extract of the
Valerian root was screened to determine its secondary metabolites and the relative abundance of some major metabolites. The infusion extract was
further evaluated for acute toxicity (LD
50), anti-inflammatory and analgesic activities in rodents.
Results: The yield of the essential oil was 0.18% w/w. The GC/MS analysis indicated the presence of 42 compounds with major ones being
caryophyllene oxide (18.11%), viridiflorol (9.37%) and bornyl acetate (8.84%). Phytochemicals found in the infusion extract were alkaloids,
saponins, tannins and flavonoids while quantitative screenings showed saponins and flavonoids accounted for 6.39% and 7.40% respectively. The
LD
50 of the extract was found to be 3808 mg/kg per oral. The infusion extract of the root (250-500 mg/kg,
p.o.) caused significant (p<0.01) activity in
the carrageenan-induced rat paw oedema model comparable to aspirin, indicating anti-inflammatory activity; but lacked analgesic activity on the
acetic acid-induced writhing test.
Conclusion: The infusion extract possessed significant anti-inflammatory but lacked analgesic activity; the present data justify the use of this herbal
agent by the herbal practitioners from the Eastern Cape region of South Africa.
