Stability testing at preformulation stages is a crucial part of drug development.
We studied physicochemical stability and biological activity of Withania somnifera (ashwagandha) dried root aqueous extract during six months real-time and under accelerated
storage conditions. The characteristic constituents of ashwagandha roots include withanolides
such as withaferin A and withanolide A. We modified and validated the HPLC‐DAD method
for quantitative measurement of withanolides and fingerprint analysis. The results
suggest a significant decline in withaferin A and withanolide A content under real
and accelerated conditions. The HPLC fingerprint analysis showed significant changes
in some peaks during real and accelerated storage (> 20 %). We also observed incidences
of clump formation and moisture sensitivity (> 10 %) under real-time and accelerated
storage conditions. These changes were concurrent with a significant decline in immunomodulatory
activity (p < 0.01) during the third month of the accelerated storage. Thus, adequate
control of temperature and humidity is important for WSE containing formulations.
This study may help in proposing suitable guidance for storage conditions and shelf
life of ashwagandha formulations.
Withania somnifera
- Solanaceae - Ayurveda - ashwagandha - stability - withaferin A - withanolide A