Adventitious root cultures of Clitoria ternatea L. and its potential as a memory enhancer alternative

Clitoria ternatea L., known as the butterfly pea plant, is from the Fabaceae family and is commonly used in traditional medicine or as a brain tonic in Asia. The root extracts of C. ternatea have been previously studied for its neuroprotective properties linked to memory enhancement of the mammalian brain, indirectly delaying the occurrence of neurodegenerative diseases. The current study aims to establish in vitro adventitious root cultures of C. ternatea via cotyledon explants and to identify the phytoconstituents of the induced adventitious roots. In this study, the highest percentage of induction (95.24%) was achieved in half-strength MS medium supplemented with 2.50 mg/L NAA (1-naphthaleneacetic acid) after 6 weeks of culture. Results also indicated that the supplementation of 1.50 mg/L NAA induced the highest number of adventitious roots (12.86 ± 2.14), while 2.50 mg/L 4-Cl-IAA (4-chloroindole-3-acetic acid) yielded higher adventitious root length (0.75 ± 0.13 cm) in comparison with the other auxin treatments. Microscopic analysis indicated thicker in vitro root morphology for all NAA treatments in comparison with the roots of in vitro seedling. Ethanolic extract of in vitro-generated adventitious roots showed potential anti-acetylcholinesterase activities (IC50 = 1519.89 ± 0.18 μg/mL) albeit being lower than the control (IC50 = 70.37 ± 0.01 μg/mL), while gas chromatography–mass spectrometry analysis identified the presence of pentacyclic triterpenes, phytosterols and fatty acids in the adventitious root culture that are linked to the mammalian neuroprotective properties of C. ternatea. The current investigation reports on the potential of C. ternatea root cultures being further utilized to produce valuable metabolites linked to the mammalian memory enhancement.