Quantitative assessment of paclitaxel in Taxus wallichiana zucc. Bark using HPTLC densitometry: Insights for germplasm selection and toxicological studies

Taxus wallichiana Zucc. [Synonym: Taxus baccata subsp. Wallichiana (Zucc.) Pilg.] or Himalayan Yew belonging to the evergreen gymnosperm family Taxaceae, grows in temperate regions and has been used in traditional medicines to treat cancer, bronchial disorders, colds, cough, etc. The plant is known to contain paclitaxel (PTX), a key bioactive component with anticancer properties. High-performance thin layer chromatography (HPTLC) was used in the present study to estimate paclitaxel from the bark of T. wallichiana obtained from 15 different geographical locations in the eastern and western Himalayas of India. HPTLC method was determined to be a reliable and efficient technique for the quantification of paclitaxel, offering rapid outcomes.The bark materials of T. wallichiana chemotype obtained from Sikkim (Samanden) contained the highest concentration of paclitaxel, followed by West Bengal (Sandakphu), Arunachal Pradesh (Dibang Valley), and respectively. The present study also examined the cytotoxicity and genotoxicity of the aqueous bark extract of the TW1 chemotype at various doses on the meristematic cells derived from the roots of Allium cepa. The bark extracts demonstrate considerable cytotoxic and mitotic properties. This study could be useful to the pharmaceutical industry for selecting elite (high paclitaxel-producing) chemotypes of T. wallichiana. The toxicological evaluation of the T. wallichiana chemotypes (using Allium cepa test) could also help to determine the genotoxic properties of the bark extract.